Klp5_ekstraksi Dan Scaling Gigi

TUGAS MATAKULIAH ILMU BEDAH VETERINER KHUSUS

JUDUL “TEKNIK OPERASI EKSTRAKSI DAN SCALING GIGI”

I NENGAH SUDARMAYASA I GEDE ARI KRISNA I PUTU GEDE WAHYU SASTRAWAN NI MADE PUTRI SURYANI KADEK AYU WINDASARI RAI JAINE DARMANTA

1209005126 1309005018 1309005019 1309005021 1309005024 1309005025

LABORATORIUM BEDAH VETERINER FAKULTAS KEDOKTERAN HEWAN UNIVERSITAS UDAYANA TAHUN 2016

i

RINGKASAN

Penyakit periodontal bersifat kronis dan progresif. Pada stadium yang lanjut, tulang rahang disekitar tulang gigi hancur dan gigi tanggal. Proses ini makan waktu bertahun-tahun. Tulang yang sudah hancur tidak dapat diperbaiki. Karena penyakit perodental disebabkan oleh karang gigi, maka karang gigi harus dihilangkan. Prosesnya disebut dental scaling. Meskipun scaling dapat dilakukan secara manual, namun yang lebih baik adalah dengan ultrasonic scaler, yaitu mengunakan getaran frekuensi tinggi untuk menghancurkan karang gigi. Metode ini tidak menyebabkan kerusakan pada lapisan email dari gigi. Karang gigi yang perlu dibersihkan bukan saja yang kelihatan, tetapi juga yang tersembunyi di bawah gusi, didalam subgingival sulcus. Gigi yang goyah harus dicabut (ekstraksi). Ekstraksi gigi adalah proses pencabutan gigi dari dalam soket dari tulang alveolar. Ekstraksi gigi dapat dilakukan dengan dua teknik yaitu teknik sederhana dan teknik pembedahan.

SUMMARY

Periodontal disease is a chronic and progressive. At an advanced stage, the jaw bone around the teeth shattered bone and tooth loss. This process process can take many years. Bone Bone that has been destroyed can’t can’t be repaired. Because periodental disease caused by tartar, the tartar must be removed. The process is called dental scaling. Although scaling can be done manually, but better is by ultrasonic scaler, which uses highfrequency vibrations to destroy tartar. This method does not cause damage to the enamel of the teeth. Tartar that needs to be cleaned not only visible, but also hidden under the gums, in the subgingival sulcus. Wobbl y tooth must be removed (extraction). Tooth extraction is the process of tooth extraction socket of alveolar bone. Tooth extraction can be done with two techniques are simple techniques and surgical technique

ii

RINGKASAN

Penyakit periodontal bersifat kronis dan progresif. Pada stadium yang lanjut, tulang rahang disekitar tulang gigi hancur dan gigi tanggal. Proses ini makan waktu bertahun-tahun. Tulang yang sudah hancur tidak dapat diperbaiki. Karena penyakit perodental disebabkan oleh karang gigi, maka karang gigi harus dihilangkan. Prosesnya disebut dental scaling. Meskipun scaling dapat dilakukan secara manual, namun yang lebih baik adalah dengan ultrasonic scaler, yaitu mengunakan getaran frekuensi tinggi untuk menghancurkan karang gigi. Metode ini tidak menyebabkan kerusakan pada lapisan email dari gigi. Karang gigi yang perlu dibersihkan bukan saja yang kelihatan, tetapi juga yang tersembunyi di bawah gusi, didalam subgingival sulcus. Gigi yang goyah harus dicabut (ekstraksi). Ekstraksi gigi adalah proses pencabutan gigi dari dalam soket dari tulang alveolar. Ekstraksi gigi dapat dilakukan dengan dua teknik yaitu teknik sederhana dan teknik pembedahan.

SUMMARY

Periodontal disease is a chronic and progressive. At an advanced stage, the jaw bone around the teeth shattered bone and tooth loss. This process process can take many years. Bone Bone that has been destroyed can’t can’t be repaired. Because periodental disease caused by tartar, the tartar must be removed. The process is called dental scaling. Although scaling can be done manually, but better is by ultrasonic scaler, which uses highfrequency vibrations to destroy tartar. This method does not cause damage to the enamel of the teeth. Tartar that needs to be cleaned not only visible, but also hidden under the gums, in the subgingival sulcus. Wobbl y tooth must be removed (extraction). Tooth extraction is the process of tooth extraction socket of alveolar bone. Tooth extraction can be done with two techniques are simple techniques and surgical technique

ii

KATA PENGANTAR

Puji syukur penulis panjatkan kehadirat Tuhan Yang Maha Esa atas berkah dan rahmat-Nya sehingga penyusunan paper ini dapat diselesaikan tepat pada waktunya. Judul paper ini adalah “Teknik Operasi Ekstraksi dan Scaling Gigi ”. Makalah ini dibuat sebagai salah satu pedoman dalam pelajaran Mata Kuliah “Ilmu Bedah Khusus Veteriner”, dimana di dalamnya membahas tentang Teknik Operasi Ekstraksi dan Scaling Gigi. Melalui penulisan makalah ini, diharapkan mahasiswa mengetahui mengenai bagaimana cara melakukan pencabutan gigi serta pembersihan karang gigi yang benar tanpa harus membahayakan pasien. Terima kasih penulis sampaikan kepada seluruh do sen mata kuliah Ilmu Bedah Khusus Veteriner yang telah membimbing dan memberikan kuliah demi lancarnya terselesaikannya tugas paper ini. Segala kritik dan saran sangat penulis harapkan demi perbaikan penulisan makalah ini. Demikianlah tugas ini penulis susun. Penulis berharap semoga bermanfaat, dan dapat memenuhi tugas matakuliah Ilmu Bedah Khusus Veteriner. Akhir kata, tidak lupa penulis ucapkan terimakasih.

Denpasar, 17 Oktober 2016

Penulis

iii

DAFTAR ISI

HALAMAN JUDUL RINGKASAN / SUMMARY…………………………………………

ii

KATA PENGANTAR…………………………………………………

iii

DAFTAR ISI…………………………………………………………..

iv

DAFTAR GAMBAR………………………………………………….

v

BAB I PENDAHULUAN 1.1 Latar Belakang……………………………………………..

1

1.2 Rumusan Masalah…………………………………………..

2

BAB II TUJUAN DAN MANFAAT 2.1 Tujuan Penulisan……………………………………………

3

2.2 Manfaat Penulisan…………………………………………..

3

BAB III TINJAUAN PUSTAKA 3.1 Penyakit Gigi pada Hewan.…………………………………

4

3.2 Penanganan Penyakit Periodontal ….………………………

5

BAB IV PEMBAHASAN 4.1 Prosedur Operasi…………………………………………….

6

4.2 Operasi……………………………………………………….

7

BAB V PENUTUP 5.1 Kesimpulan…………………………………………………..

9

5.2 Saran…………………………………………………………

9

DAFTAR PUSTAKA…………………………………………………..

10

LAMPIRAN……………………………………………………………

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iv

DAFTAR GAMBAR

Gambar 1. Three-ways syringe yang digunakan untuk mendesinfeksi ruang mulut. Three-ways syringe dapat mengeluarkan air, chlorhexidine rinse dan udara………………………………………… 8

v

BAB I PENDAHULUAN

1.1 Latar Belakang

Indonesia sebagai negara berkembang membuat pola hidup masyarakat mengikuti gaya di negara maju. Salah satu gaya hidup yang diikuti adalah memiliki hewan kesayangan. Kucing dan anjing merupakan hewan peliharaan yang umum dimiliki oleh masyarakat. Terdapat beberapa faktor yang mempengaruhi kesehatan kucing seperti faktor diet, stress, jenis ras, penyakit infeksius, dan penyakit periodontal (DeLaurier et al . 2006). Penyakit periodontal sangat sering dihadapi oleh dokter hewan praktisi (Klein 2000). Hal tersebut membuat klien menanyakan penyakit periodontal pada hewan kesayangan mereka (Gorrel 2008). Faktor yang menyebabkan timbulnya penyakit periodontal adalah kebiasaan menggigit, grooming , status kesehatan, perawatan di rumah, bakteri yang aktif di ruang mulut, serta jenis pakan yang diberikan (Gawor et al . 2006). Penyakit periodontal bersifat kronis dan progresif. Pada stadium yang lanjut, tulang rahang disekitar tulang gigi hancur dan gigi tanggal. Proses ini memerlukan waktu bertahun-tahun. Tulang yang sudah hancur tidak dapat diperbaiki. Karena penyakit perodental disebabkan oleh karang gigi, maka karang gigi harus dihilangkan. Prosesnya disebut dental scaling . Meskipun scaling dapat dilakukan secara manual, namun yang lebih baik adalah dengan ultrasonic scaler , yaitu mengunakan getaran frekuensi tinggi untuk menghancurkan karang gigi. Metode ini tidak menyebabkan kerusakan pada lapisan email dari gigi. Karang gigi yang perlu dibersihkan bukan saja yang kelihatan, tetapi juga yang tersembunyi di bawah gusi, didalam subgingival sulcus. Gigi yang goyah harus dicabut (ekstraksi). Ekstraksi gigi adalah proses pencabutan gigi dari dalam soket dari tulang alveolar. Ekstraksi gigi dapat dilakukan dengan dua teknik yaitu teknik sederhana dan teknik pembedahan. Teknik sederhana dilakukan dengan melepaskan gigi dari perlekatan jaringan lunak menggunakan elevator kemudian menggoyangkan dan mengeluarkan gigi di dalam soket dari tulang alveolar menggunakan tang ekstraksi. Sedangkan teknik pembedahan dilakukan

dengan

pembuatan

flep,

pembuangan

tulang

disekeliling

gigi,

1

menggoyangkan dan mengeluarkan gigi di dalam soket dari tulang alveolar kemudian mengembalikan flep ke tempat semula dengan penjahitan. Teknik sederhana digunakan untuk ekstraksi gigi erupsi yang merupakan indikasi, misalnya gigi berjejal. Ekstraksi gigi dengan teknik pembedahan dilakukan apabila gigi tidak bisa diekstraksi dengan menggunakan teknik sederhana, misalnya gigi ankilosis.

1.2

Rumusan Masalah

1.2.1 Apa pengertian dari ekstraksi dan scaling gigi? 1.2.2 Apa saja indikasi teknik operasi ekstraksi dan scaling gigi? 1.2.3 Bagaimana teknik operasi ekstraksi dan scaling gigi? 1.2.4 Bagaimana perawatan pasca operasi ekstraksi dan scaling gigi?

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BAB II TUJUAN DAN MANFAAT 2.1

Tujuan Penulisan

Penulisan paper ini bertujuan untuk : 2.1.1 Memberikan penjelasan tentang operasi ekstraksi dan scaling gigi 2.1.2 Memberikan penjelasan tentang apa saja indikasi pada operasi ekstraksi dan scaling gigi 2.1.3 Memberikan penjelasan bagaimana teknik pada operasi ekstraksi dan scaling gigi 2.1.4 Memberikan

penjelasan

tentang

perawatan

pasca

operasi

ekstraksi dan scaling gigi

2.2

Manfaat Penulisan

2.2.1 Sebagai bahan acuan untuk pembelajaran bagi kami mahasiswa dalam memahami mengenai persiapan, teknik operasi dan perawatan pasca operasi ekstraksi dan scaling gigi 2.2.2 Dapat mengaplikasikan manajemen preoperasi dan pascaoperasi dengan prosedur yang baik dan benar dengan tujuan yang tepat

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BAB III TINJAUAN PUSTAKA 3.1 Penyakit Gigi pada Hewan

Penyakit pada gigi dan jaringan disekitar gigi disebut dengan penyakit periodontal. Penyebab penyakit periodontal adalah malocclusion, supernumery pada gigi, dan aktivitas bakteri Gram-positif dan Gram-negatif (Holmstrom et al. 2013b). Penyakit periodontal mengakibatkan kerusakan pada ligamen periodontal dan alveolar bone. Gingivitis adalah peradangan pada gusi dan sebagai tanda awal dari penyakit periodontal (Holmstrom et al . 2013b). Penyakit periodontal ditandai dengan bau mulut yang tidak sedap yang berhubungan dengan nekrosis dan infeksi (Perrone 2013). Gingivitis yang tidak ditangani dapat berkembang menjadi periodontitis. Periodontitis adalah kerusakan yang diikuti dengan hilangn ya struktur pendukung dari gigi termasuk periodontium, gingiva, ligamen, cementum, dan alveolar bone. Gingivitis tidak menyebabkan hilangnya perlekatan gigi pada gusi, namun periodontitis menyebabkan hilangnya perlekatan gigi pada gusi (Gorrel 2008). Gingivitis dapat disembuhkan jika kausa dihilangkan, sedangkan periodontitis umumnya tidak dapat disembuhkan (Harvey 2005). Peradangan

menjadi

lebih

intensif

saat

gingivitis

berlanjut

menjadi

periodontitis. Peradangan tersebut akan menyebabkan kerusakan pada jaringan, memicu gingival recession, dan membentuk pocket periodontal (Niemeic 2008b). Komposisi dari calculus pada gigi adalah mineral organik dan anorganik. Brushite, dicalcium

phosphate

dehydrate,

octacalcium

phosphate,

hydroxyapatite dan

whitlockite adalah komponen yang membentuk calculus. Fosfolipid berperan penting dalam pembentukan calculus. Calculus selalu dilapisi oleh lapisan tipis dari mikroorganisme. Kerusakan gigi akan diikut dengan terjadinya penyerapan protein dari saliva. Bakteri Gram-negatif akan ikut terserap mendominasi terbentuknya lapisan biofilm plak. Plak menyerap kalsium dan fosfat dari saliva untuk membentuk supragingival calculus dan cairan crevicular akan membentuk subgingival calculus ( Jin dan Yip 2002).

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3.2 Penanganan Penyakit Periodontal

Penyakit periodontal adalah infeksi lokal yang harus lebih diperhatikan. Telah banyak dilaporkan kasus yang berhubungan antara penyakit periodontal dengan penyakit sistemik. Bakteri dan hasil metabolismenya masuk ke dalam sistem sirkulasi melalui ruang mulut saat mengunyah. Bakteri Gram-negatif dilaporkan menginduksi lesio seperti artherosklerosis pada hewan coba dan dilaporkan juga pada studi di manusia. Penanganan penyakit periodontal bertujuan untuk menghilangkan penyebab penyakit dan mencegah kerusakan lebih lanjut. Identifikasi dan penanganan mempengaruhi efektivitas pencegahan. Penanganan penyakit periodontal dibedakan menjadi dua jenis yaitu penanganan non-operasi dan penanganan dengan operasi (Caiafa 2006). Penanganan non-operasi bertujuan untuk pencegahan dan pengendalian penyakit periodontal. Penanganan non-operasi dilakukan dengan menghilangkan plak atau calculus pada gigi dan disebut dental scaling . Penanganan non-operasi dilakukan pada gigi dengan deposit calculus pada permukaan gigi namun perlekatan gigi pada gusi masih baik (Gorrel 2008). Scaling dapat dilakukan manual menggunakan forceps atau dengan peralatan ultrasonic scaler (Bellows 2010). Penanganan dengan operasi dilakukan dengan pencabutan atau extraction. Pencabutan gigi dilakukan ketika gigi tidak dapat diselamatkan atau klien tidak dapat melakukan perawatan di rumah. Gigi tidak dapat diselamatkan ketika pulpa telah mengalami trauma (Bellows 2010). Pencabutan pada gigi akar satu dan gigi berakar lebih dari satu memiliki cara yang berbeda. Gigi berakar lebih dari satu perlu dipotong menjadi bagian-bagian gigi yang berakar satu (Niemeic 2008a).

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BAB IV PEMBAHASAN 4.1 Prosedur Operasi

4.1.1 Pemeriksaan Fisik Hewan Hewan diperiksa keadaan fisiknya. Pemeriksaan ini bertujuan untuk mengetahui keadaan fisik hewan, perubahan yang terjadi dan evaluasi preanestesi. Pemeriksaan fisik meliputi pengukuran berat badan menggunakan timbangan, pengukuran suhu tubuh hewan menggunakan termometer, menghitung frekuensi napas dan frekuensi jantung per menit menggunakan stetoskop.

4.1.2 Metode Anastesi Anestesi dilakukan dengan pemberian premedikasi terlebih dahulu melalui rute subkutan. Premedikasi yang digunakan adalah atropin sulfat. Atropin sulfat adalah sediaan anti kolinergik. Atropin sulfat digunakan untuk mencegah terjadinya bradikardia (Vesal et al . 2011). Pemberian premedikasi bertujuan untuk menetralkan efek samping yang tidak diinginkan dari sediaan anestetikum dan dapat menurunkan dosis anestesi (Lee 1998). Atropin sulfat : Jumlah pemberian = (berat badan ×dosis aplikasi )/ (kandungan sediaan). Kombinasi ketamine dan xylazine diberikan untuk anestesi umum melalui rute intravena. Kombinasi ketamine dan xylazine digunakan karena ketamine memiliki efek samping terjadinya kekakuan otot dan xylazine merupakan sediaan yang dapat merelaksasikan otot. Efek samping dari xylazine yaitu muntah dapat diatas dengan pemberian premedikasi atropin sulfat (Lukasik 2014). Dosis Xylazin = (berat badan ×dosis aplikasi )/(kandungan sediaan). Dosis Ketamin = (berat badan ×dosis aplikasi )/(kandungan sediaan). Saat hewan mulai hilang kesadarannya, endotracheal tube ukuran 2 mm dipasang pada hewan. Pemasangan endotracheal tube dibantu dengan laryngoscope untuk melihat posisi epiglotis. Tanda bahwa endotracheal tube masuk pada saluran pernapasan adalah hewan sedikit tersedak dan keluar udara melalui lubang endotracheal tube. Isofluran sebagai anestesi per inhalasi diberikan setelah endotracheal tube terpasang. Maintenance isofluran dilakukan sepanjang proses operasi penyakit periodontal. Tujuan dari pemasangan 6

endotracheal tube adalah untuk mempermudah proses maintenance anestesi secara per inhalasi. Sediaan anestesi per inhalasi yang digunakan adalah isofluran. Isofluran digunakan karena induksinya yang halus dan cepat, pemulihannya yang cepat, dan kelarutannya dalam darah rendah (Capey 2007). Anestesi per inhalasi umum digunakan pada operasi yang membutuhkan waktu yang panjang. Keuntungan dari penggunaan anestesi perinhalasi adalah kedalaman anestesi mudah dikendalikan, kesadaran dapat kembali dengan cepat (Lee 1998), dan mencegah masuknya debris dari calculus ke dalam trakea (Bednarski et al. 2011).

4.1.3 Persiapan Operator dan Asisten Langkah-langkah yang harus dilakukan oleh operator dan asisten adalah menggunakan tutup kepala dan masker, mencuci kedua tangan dengan sabun dan menyikatnya dengan sikat pada air yang mengalir. Pencucian dimulai dari ujung jari yang paling steril kemudian dibilas dengan arah dari ujung jari kelengan yang dilakukan sebanyak 10-15x. Setelah selesai mencuci tangan dan membilasnya, keran ditutup dengan siku untuk mencegah kontaminasi. Kemudian tangan dikeringkan dengan handuk dan glove dipakai. Setelah semua langkah dilalui, operasi siap dilakukan.

4.2 Operasi Pencabutan gigi dilakukan pada gigi yang perlekatannya dengan gusi sudah buruk. Pencabutan untuk tiap gigi memiliki cara yang berbeda, karena jumlah akar gigi yang berbeda. Pencabutan gigi yang memiliki satu akar, diawali dengan dikuranginya perlekatan gigi dengan gusi dengan menggunakanelevator . Gigi dicabut menggunakan extraction forceps. Pencabutan gigi dilakukan ketika gigi sudah bebas perlekatannya dengan gusi. Pencabutan gigi dengan akar lebih dari satu, pertama-tama gigi dibagi berupa segmen sehingga gigi menjadi beberapa bagian yang berakar satu. Segmen tersebut dibuat dengan menggunakan bor gigi. Gigi yang telah berakar satu kemudian dikurangi perlekatannya dengan gusi menggunakan elevator . Gigi yang sudah berkurang perlekatannya dicabut menggunakan extraction forceps. Kuret dilakukan

7

pada gusi setiap selesai mencabut satu gigi untuk mencegah adanya bagian dari gigi yang tertinggal. Proses desinfeksi dilakukan pada lubang alveolar bone menggunakan chlorhexidine rinse dengan bantuan alat 3-ways syringe. Penjahitan pada gusi dilakukan pada lubang alveolar bone yang cukup besar. Penjahitan dilakukan dengan benang polyglycoli acid ukuran 4/0 dan jarum regular taper point ½ circle. Teknik penjahitan yang digunakan adalah simple interrupted. Penanganan pasca operasi adalah dengan pemberian chlorhexidine rinse selama 5-7 hari untuk menurunkan tingkat akumulasi plak, menurunkan risiko infeksi dan peradangan (Oxford 2013).

Gambar 1 Three-ways syringe yang digunakan untuk mendesinfeksi ruang mulut. Three-ways syringe dapat mengeluarkan air, chlorhexidine rinse dan udara.

8

BAB V PENUTUP 5.1 Kesimpulan

Penyakit periodontal bersifat kronis dan progresif. Pada stadium yang lanjut, tulang rahang disekitar tulang gigi hancur dan gigi tanggal. Proses ini makan waktu bertahun-tahun. Tulang yang sudah hancur tidak dapat diperbaiki. Karena penyakit perodental disebabkan oleh karang gigi, maka karang gigi harus dihilangkan. Prosesnya disebut dental scaling. Meskipun scaling dapat dilakukan secara manual, namun yang lebih baik adalah dengan ultrasonic scaler, yaitu mengunakan getaran frekuensi tinggi untuk menghancurkan karang gigi. Gigi yang goyah harus dicabut (ekstraksi). Ekstraksi gigi adalah proses pencabutan gigi dari dalam soket dari tulang alveolar. Ekstraksi gigi dapat dilakukan dengan dua teknik yaitu teknik sederhana dan teknik pembedahan. Sebelum dilakukan operasi, dokter harus memeriksa keadaan hewan. Setelah itu lakukan pramedikasi dengan atropine sulfat lalu dilanjutkan dengan pemberian ketamine serta xylazin. Setelah itu gunakan anestesi per-inhalasi dengan isoflurin yang diberikan setelah endotracheal tube terpasang. Lakukan persiapan operator, lalu lakukan operasi.

5.2 Saran Diharapkan dilakukan penelitian lagi tentang ekstraksi dan scaling gigi, sehingga lebih banyak lagi referensi yang dapat digunakan oleh penulis.

9

DAFTAR PUSTAKA

Bednarski R, Grimm K, Harvey R, Lukasik VM, P enn WS, Sargent B, Spetts K. 2011. AAHA anesthesia guidelines for gogs and cats. J Am Aim Hosp Assoc. 47: 377 – 385. doi: 10.5326/JAAHA-MS-5846. Bellows J. 2010. Feline Dentistry: Oral Assessment, Treatment, and Preventative Care. Iowa (US): J Wiley. hlm 181, 196. Capey S. 2007. The Comprehensive Pharmacology. Philadelphia (US): Elsevier Science. hlm 1 – 4. DeLaurier A, Boyde A, Horton MA, Price JS . 2006. Analysis of the surface characteristics and mineralization status of feline teeth using scanning electron microscopy. J Compilation. 209(5): 655 – 669. doi: 10.1111/j.14697580.2006.00643.x. Gawor JP, Reiter AM, Jodkowska K, Kurski G, Wojtacki MP, Kurek A. 2006. Influence of diet on oral health in cats and dogs. J Nutrition. 136(7):2021 – 2023. Gorrel C. 2008. Small Animal Dentistry. Nind F, editor. Philadelphia (US): Elsevier Science. hlm 13, 21, 22, 23, 39. Harvey CE. 2005. Management of periodontal disease: understanding the option. Science Direct . 35(4):819 – 836. doi:10.1016/j.cvsm.2005.03.002. Holmstrom SE (b), Bellows J, Juriga S, Knutson K, Niemeic BA, P errone J. 2013. Dental care guidelines for dogs and cats: veterinary practice guidelines. JAAHA. hlm 76. Jin Y, Yip H. 2002. Supragingival calculus: formation and control. CROBM. 13(5): 426 – 441. doi: 10.1177/154411130201300506. Klein T. 2000. Predisposing factor and gross ex amination findings in periodontal disease. Science Direct . 15(4):189 – 196. doi:10.1053/svms.2000.22244. Lee L. 1998. Canine and Feline Anesthesia [Internet]. [Diunduh 2015 Juli 4 ]. Tersedia pada: https://instruction.cvhs.okstate.edu/vmed5412/pdf/22CanineFelineAnesthesia.pdf. Lukasik VM. 2014. Understanding the unwanted side effects of the anesthesia drugs. Didalam: Australasian Structural Engineering 2014. [Internet].[2014 Juli 11-9 di Sky City Auckland]. Niemeic BA (a). 2008. Extraction techniques. ProQuest. 23(2):97 – 105. doi:10.1053/j.tcam.2008.02.006. Niemeic BA (b). 2008. Periodontal disease. ProQuest . 23(2):72 – 80.doi:10.1053/j.tcam.2008.02.003.

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Oxford M. 2013. Feline chronic gingvostomatitis – treatment and management option. Vet Times.[Internet]. [diunduh 2016 Oktober 15]. Tersedia pada: http://www.vetsonline.com/media/a65/a26b7c5e1bef0a0a76577ace8e190.pdf . Perrone JR. 2013. Small Animal Dental Procedures for Veterinary Technicians and Nurses. Iowa (US): J Wiley. hlm 4, 5, 14, 15, 25, 26, 96, 97. Vesal N, Sarchachi AA, Nikahval B, Karampour A. Clinical evaluation of the sedative properties of acepromazine-xylazine combination with or without atropine and their effect on physiologic values in dogs. Vetertinarski Arhiv. 81(4): 485 – 489.

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J. Anat. (2006) 209, pp655–669

doi: 10.1111/j.1469-7580.2006.00643.x

Analysis of the surface characteristics and mineralization status of feline teeth using scanning electron microscopy BlackwellPublishing Ltd

A. DeLaurier,1 A. Boyde,2 M. A. Horton1 and J. S. Price3 1

Bone and Mineral Centre, Department of Medicine, University College London, UK Biophysics, Oral Growth and Development, St Barts and the London School of Medicine and Dentistry, Queen Mary, University of London, UK 3 The Royal Veterinary College, London, UK 2

Abstract External resorption of teeth by odontoclasts is a common condition of unknown origin affecting domestic cats. Odontoclastic resorptive lesions involve the enamel cementum junction (ECJ, cervix) and root surface, leading to extensive loss of enamel, dentine and cementum. This study was undertaken in order to determine whether features of the surface anatomy and mineralization of feline teeth could explain why odontoclastic resorptive lesions are so prevalent in this species. Backscattered electron scanning electron microscopy was used to study enamel, cementum and dentine in non-resorbed, undemineralized teeth from adult cats. Analysis of the ECJ revealed thin enamel and cementum and exposed dentine at this site. Furthermore, enamel mineralization decreased from the crown tip to the ECJ, and dentine mineralization was lowest at the ECJ and cervical root. Analysis of cementum revealed variations in the organization and composition of fibres between the cervical, mid- and apical root although no significant differences in mineralization of cementum were detected between different regions of the root. Reparative patches associated with resorption of cementum by odontoclasts and repair by cementoblasts were present on the root surface. In conclusion, results suggest that the ECJ and cervical dentine could be at a greater risk of destruction by odontoclasts compared with other regions of the tooth. The relationship of these features to the development and progression of resorption now requires further examination. Key words cats; dental cementum; dental enamel; dentine; tooth resorption.

Introduction

2001; Reiter et al. 2005). Clinical and histological studies

Domestic cats are predisposed to external resorption of

have identified lesions as external, subgingival defects that initiate on the surface of the tooth root and

the teeth by odontoclasts, leading to destruction of the periodontal attachment and tooth loss (Hopewell-Smith, 1930; Schneck & Osborn, 1976; Schlup, 1982; Lyon,

progress to involve dentine. As the disease progresses, lesions become filled with vascular granulation tissue, and reparative activity may occur (Hopewell-Smith, 1930;

1992). Feline odontoclastic resorptive lesions (FORLs) are reported to occur in 26–72.5% of cats, and the

Schneck & Osborn, 1976; Schlup & Stich, 1982; Reichart et al. 1984; Okuda & Harvey, 1992; Ohba et al. 1993;

incidence of the causative disease increases with age

Okuda et al. 1995; Gorrel & Larsson, 2002; Roes &

(Schlup, 1982; Coles, 1990; Crossley, 1991; Harvey, 1992;

Mollenbeck, 2003; Mollenbeck, 2004; Roes, 2004).

van Wessum et al. 1992; Gengler et al. 1995; Lund et al. 1998; Lommer & Verstraete, 2000, 2001; Ingham et al.

Various factors have been suggested to underlie the disease, such as periodontal disease, dietary factors, mechanical stress, developmental tooth defects, breed

Correspondence Dr April DeLaurier, Division of Developmental Biology, National Institute for Medical Research, The Ridgeway, Mill Hill, London NW7 1AA, UK. T: +44 208959 3666 ext. 2095; F: +44 208816 2526; E: [email protected] Accepted for publication 10 August 2006 © 2006 The Authors Journal compilation © 2006 Anatomical Society of Great Britain and Ireland

and viral disease, although none of these factors has been definitively proven to be the direct cause of resorption (see review by Reiter & Mendoza, 2002). Recently, a significant association between the presence of lesions and elevated serum 25-hydroxyvitamin

656 Surface characteristics and mineralisation of feline teeth, A. DeLaurier et al.

D and low urine specific gravity has been established (Reiter et al. 2005). FORLs have also been reported in exotic cat species (Berger et al. 1995, 1996a; Mendoza

Materials and methods

et al. 2000). In humans, a similar rare condition has been described as idiopathic resorption (Postlethwaite & Hamilton, 1989; Moody & Muir, 1991; Liang et al.

Upper and lower jaws were obtained from a number of veterinary sources. All cats were euthanized for reasons unrelated to this research. Details of age, gender, neuter

2003).

status, general health and dietary history were not

Resorption has been reported to involve the enamel cementum junction (ECJ, referred to as ‘neck lesions’),

known for most specimens. Intact left and right upper and lower jaws were removed using standard dissec-

and the tooth root surface apical to the ECJ (Schlup &

tion tools and were radiographed using a digital dental

Stich, 1982; Reichart et al. 1984; Okuda & Harvey, 1992;

radiography unit (RVG™, Trophy, France). Dentitions

Ohba et al. 1993; Gauthier et al. 2001; Gorrel & Larsson, 2002; Roes & Mollenbeck, 2003; Harvey et al. 2004

with radiographic evidence of alveolar bone loss, fractured teeth, resorptive lesions, ankylosis or periapical

DeLaurier et al. 2005). To date, light microscopy and scanning electron microscopy (SEM) studies of the feline tooth have described the development and structure of

abscesses were excluded from analysis. All teeth used in the study were from cats with evidence of a permanent dentition where all teeth showed fully closed root

enamel, dentine, cementum and periodontal ligament (Boyde, 1964, 1969a, 1989; Forsberg et al. 1969; Silva

apices. Dentitions were fixed in formaldehyde (from 4% paraformaldehyde in phosphate-buffered saline,

& Kailis, 1972; Kallenbach, 1976; Nalbandian & Frank,

pH 7.4) for 1 week at 4 °C, washed in distilled H2O and

1980; Hayashi, 1983; Sasaki et al. 1984, 1985; Skobe et al. 1985; Jones & Boyde, 1988; Bishop et al. 1991;

stored in 70% ethanol at room temperature. In total, 56 teeth from the dentitions of seven cats were used

Nanci et al. 1992; Okuda & Harvey, 1992; Orsini &

for the surface SEM study (Table 1). Thirty-six teeth

Hennet, 1992; Vongsavan & Matthews, 1992; Crossley,

from the dentitions of ten cats were embedded in

1995; Berger et al. 1996b; Colley et al. 2002). However, few studies have focused on those structures that are

PMMA (see below) and the sectioned block surface polished and used for quantitative SEM analysis.

Samples

critical to the understanding of how tissues may be involved in the progression of FORLs, namely the surface features of the ECJ and the root. As a result,

Preparation of samples for surface analysis

the relationship between these structures and disease remains unclear.

Intact jaws were digested in distilled H2O with 2% Tergazyme™ (alkaline bacterial pronase, Alconox Inc.,

The present study was undertaken to describe the

New York, USA), at 50 °C in a shaker at 50 r.p.m. until

structural anatomy of non-resorbed feline teeth and thus provide a basis for future investigation of the rela-

no soft tissue could be detected visually (approximately

tionship between these features with the progression of FORLs. Back scattered electron SEM was used to characterize the surface anatomy of undemineralized, teeth, and to analyse the relative mineralization of enamel, dentine and cementum at different locations on the tooth. We have focused on the surface anatomy of the tooth as FORLs begin on the external surface of

Table 1 Details of specimens used for surface and section SEM analysis Side

Teeth

Surface

Section

Upper jaw

First, second, and third incisors Canines Second premolar Third premolar Fourth premolar First molar First, second, and third incisors Canines Third premolar Fourth premolar First molar

9 5 5 3 6 3 5 5 5 5 5 56

1 3 3 3 3 2 0 3 6 6 6 36

the root and progress inwards. Previous microscopic and in vitro studies have demonstrated an increased rate of osteoclastic resorption in tissues which are less mineralized (Reid, 1986; Jones et al. 1995; Lu et al. 1999; Gentzsch et al. 2005). Therefore, the relative mineral-

Lower jaw

ization of different regions of the tooth was also analysed, as variations in mineralization between regions of the tooth may determine differences in the rate of destruction of different tissues by odontoclasts.

Total

© 2006 The Authors Journal compilation © 2006 Anatomical Society of Great Britain and Ireland

Surface characteristics and mineralisation of feline teeth, A. DeLaurier et al. 657

6 weeks). Samples were rinsed for 1–2 h in running tap water, followed by several rinses in distilled H2O, and then air dried. Teeth were carefully removed from

7–10 days. MMA containing a polymerizing catalyst (Azo-isobutyronitrile, BDH, UK, referred to as PMMA) was added and degassed under vacuum. Specimens

alveolar bone using bone-cutting forceps, such that alveolar bone surrounding the tooth was cut away until the tooth root was fully exposed and could be

were left in PMMA at room temperature under normal indoor light conditions until the PMMA was completely set; in most cases, this occurred within 3 weeks. Where

removed from the bone. Throughout this process, jaws

PMMA would not set, specimens were placed in a 37 °C

and teeth were examined under a dissecting microscope to assess any signs of pathology or of damage

incubator overnight or until PMMA appeared to thicken and then allowed to continue to set at room temperature.

during processing – any such teeth were eliminated

Following complete polymerization, embedded teeth

from the study. To remove any remaining soft tissue,

were sectioned using a diamond saw (Isomet™, Buehler,

loose teeth were treated with NaOCl (3% available chlorine) at room temperature for 2 weeks. Samples

Coventry, UK) for SEM analysis. Incisors, canines, premolars and molars were sectioned longitudinally, slightly

were thoroughly washed in distilled water, air dried, mounted on aluminium rivets using conductive carbon putty (Leit-C Plast™, Agar Scientific, Stansted, UK) and

offset from the centre of roots (Fig. 1A). Both the mesial and the distal roots of multirooted premolars and molars were sectioned and analysed separately.

coated with carbon by evaporation.

The specimen surface was ground using polishing paper (400–1200 grit, MetPrep, Coventry, UK) until the

Surface analysis using SEM

surface was as close to the central plane of the root as

Teeth were examined using a JEOL 5410LV™ SEM

possible. The surface was polished on a cloth with 6-µm diamond paste, followed by 1-µm paste (MetPrep).

(JEOL, Welwyn Garden City, UK) with an accelerating

Multiple blocks were fastened to an aluminium plate

voltage set at 15 or 20 kV. Images were recorded using

and sputter-coated with carbon as described above.

digital image acquisition software (Printerface™, GW Electronics, Norcross, Georgia, USA). A calibration

Halogenated dimethacrylate standards of known backscattering coefficients (see below) were added to the

standard (Planotech™, Agar Scientific) with intervals of

plate for analysis of relative backscattering of samples

10 µm was used to calculate field width. The buccal surfaces (i.e. tooth surfaces facing the

(Banerjee & Boyde, 1998).

cheeks or lips) were examined, except when they were damaged or unclean, in which case the lingual/palatal

BSE SEM analysis of embedded specimens

surfaces (i.e. tooth surfaces facing tongue or palate)

PMMA blocks were examined using backscattered

were analysed. High-magnification images (500× and 1000×) were recorded of the ECJ, the cervical root, mid-

electron (BSE) mode, on a Zeiss DSM (digital scanning microscope; 962™, Zeiss, Welwyn Garden City, UK)

root and apical root surfaces. In cases of multirooted

using an annular solid-state BSE detector (KE Electronics,

teeth, the buccal or lingual/palatal surfaces of both the

Toft, Comberton, Cambs., UK). Blocks were examined

mesial and the distal roots were examined. The average diameter of cementum fibres and cementocyte lacunae

at an accelerating voltage of 20 kV, a beam current of 0.5 nA and working distance 17 mm, giving 11 mm

were measured using a calibration standard used in the

sample to BSE detector clearance. Images were recorded

microscope.

under external computer control (Kontron Elektronik, Munich, Germany).

Whole jaws were cleared in xylene in glass jars under

Both buccal and lingual/palatal surfaces of longitudinal sections of teeth were examined. High-magnification images (50×, 150×, 500×) were recorded at six locations

vacuum for 15–30 min and then left at room temperature on a shaker in xylene for 7–10 days. The xylene was

on the tooth surface including the crown tip, buccal and lingual/palatal ECJs, the cementum at the cervical

decanted and the specimens were covered with

root, mid-root and at the apical root. Images were

methylmethacrylate (MMA, BDH, UK). Specimens were

taken for analysis of features of the tooth in section,

degassed under vacuum, lids were secured with plastic film and jars were placed on a rotating platform for

including tissue thickness, the average diameter of features of enamel and dentine, and mineralization.

Embedding and sectioning of specimens



Table 2 Backscattering coefficient of halogenated dimethacrylate standards, PMMA, bone, dentine, and enamel Mean backscattering coefficient Monobromo: C 22H25O10Br Tetrabromo: C 22H24O10Br4 PMMA: H8C5O2 Bone and dentine Enamel

0.125* 0.195* 0.082* 0.135–0.151* 0.179†

*Howell & Boyde (1998); †Howell (unpublished data).

Analysis of mineralization Three halogenated dimethacrylate standards of known backscattering coefficients covering the backscattering range of mineralized dental tissues were attached to the plate and were used to calibrate specimens (Table 2) (for details of method, see Boyde et al. 1995; Banerjee & Boyde, 1998; Howell & Boyde, 1998). The grey levels of standards were used to scale tooth images so that a monobrominated standard (MBr) represented a grey level of 0 (black) and a tetrabrominated standard (Br4) represented a grey level of 255 (white). Relative grey level was used as an indicator of mineralization; less mineralized tissues appear dark grey, and more mineralized tissues appear light grey or white. Measurement of enamel, dentine and cementum

Fig. 1 Schematic diagrams illustrating the sectioning and analysis of methacrylate-embedded teeth. (A) Teeth were sectioned longitudinally, slightly offset from the centre of roots (plane of section indicated by dotted lines). Both the mesial and the distal roots of multirooted premolars and molars were sectioned and analysed separately. The specimen surface was ground until the surface was as close to the central plane of the root as possible. (B) Locations where mineralization was measured in sectioned teeth. 1. Crown tip enamel (surface enamel, inner enamel, and enamel dentine junction) and crown tip dentine. 2. Mid-crown enamel (surface enamel and enamel dentine junction) and mid-crown dentine. 3. Enamel and dentine and the enamel cementum junction. 4. Cervical root cementum and dentine. 5. Mid-root cementum (surface cementum and cementum dentine junction) and dentine. 6. Apical root cementum (surface cementum and cementum dentine junction) and dentine.

mineralization was calculated from standardized grey level images analysed using SigmaScan Pro™ image analysis software. Grey levels were analysed from 50× magnification images. Mineralization was measured at 17 locations on the tooth, including the crown tip enamel (surface enamel, inner enamel and enamel at the enamel dentine junction, referred to as EDJ) and crown tip dentine, mid-crown enamel (surface enamel and enamel at the EDJ) and mid-crown dentine, the ECJ enamel and dentine, the cervical root cementum and dentine, the mid-root cementum (surface cementum and cementum at the cementum dentine junction, referred to as CDJ) and mid-crown dentine, and the apical

The thickness of enamel (crown tip, mid-crown and ECJ within 250 µm coronally) and cementum (ECJ within 250 µm apically) at the cervical root, mid-root and root apex were measured using SigmaScan Pro™ image analysis software (SPSS Science, Chicago, USA). Differences in tissue thickness and distance were compared statistically between locations on the tooth using ANOVA (SPSS™, SPSS Science).

root cementum (surface cementum and cementum at the CDJ) and apical root dentine (Fig. 1B). Grey levels were calculated by measuring mean pixel intensity over an area of 202 pixels (approximate area = 1800 µm2). Grey level values were compared statistically between locations on the tooth using ANOVA. Owing to limited sample numbers of each tooth type, pixel intensity measurements could not be compared statistically between teeth.



Fig. 2 Surface and section features of enamel (EP = enamel prisms). (A) Enamel prisms of a left upper first molar exposed through wear (scale bar = 25 µm). (B) Developing enamel surface morphology of a lower right fourth premolar showing enamel prisms (pit floor) and interpit enamel (IP, scale bar = 20 µm). (C) Developing enamel surface morphology showing ‘cobbles’ (CB) surrounded by prism-free enamel on the crown surface coronal to the enamel cementum junction (ECJ) in a left upper fourth premolar (scale bar = 25 µm). (D) Enamel of a lower left third premolar fractured post-mortem, showing horizontal sections through enamel prisms, which are orientated in alternate directions forming Hunter–Schreger bands, the prism-free surface enamel layer (PFE), and the enamel dentine junction (EDJ) (scale bar = 50 µm).

Results Surface characteristics of the tooth

tudinal enamel prisms were present, organized in Hunter–Schreger bands (Fig. 2D). In this tooth, a layer of prism-free enamel at the surface of the crown was

The enamel was assessed in 34 teeth. In all cases, the surface was primarily smooth and featureless, with no

also observed. Among teeth with exposed dentine tubules at the

evidence of perikymata or features associated with the

cervical root (Fig. 3A), the area of exposed dentine

external ends of enamel prisms (rods). Ten teeth (29%)

extended from the ECJ for distances that ranged from

had wear on the crown, revealing the prism structure underlying surface enamel (Fig. 2A). Nine teeth (26%) showed areas of developing enamel surface morpho-

20 µm up to several millimetres apically. In a tooth that was fractured post-mortem, dentine tubules radiated from the pulp chamber, and could be detected extend-

logy, including enamel prisms and interpit enamel, in the fissures between cusps (Fig. 2B). In three teeth (9%), a band of ‘cobbled’ enamel, in which the prism-free

ing to the EDJ (Fig. 3B). The ECJ structure was studied in 50 teeth, although the enamel margin could only be assessed in 28 teeth

surface enamel otherwise covering the tooth was missing, was detected 50–100 µm coronally from the

as there was cracking and fracture of enamel at this location among remaining teeth. The enamel margin

ECJ (Fig. 2C). In a tooth fractured post-mortem, longi-

had a ‘cobbled’ appearance and comprised circular



Fig. 3 Surface and section features of dentine. (A) Dentine tubules (DT) exposed at the cervical root surface adjacent to cementum featuring extrinsic fibre bundles (EFB) on a left upper third premolar. (B) Upper left third premolar fractured post-mortem, showing dentine tubules (DT) radiating from the pulp chamber to the enamel dentine junction (EDJ) (D = dentine, E = enamel). All scale bars = 25 µm.

projections 3–10 µm in diameter, extending in a band 10–50 µm coronally from the ECJ in 18 (64%) teeth (Fig. 4A), and was porous in nine (32%) teeth (Fig. 4B). In one sample (4%), cementum overlapped enamel, and the enamel margin could not be assessed (Fig. 4C). The root surface at the ECJ was assessed in all 50 teeth. In the majority of cases (34 teeth), the ECJ was associated with a porous root surface with exposed dentine tubules (68%, Fig. 4B). Fibrillar cementum with dense extrinsic fibre bundles 2–5 µm in diameter contacting enamel occurred in the remaining 16 teeth (32%, Fig. 4A). The entire root surface of the tooth was examined to determine if there were differences in surface anatomy between cervical, mid-root and apical regions. Extrinsic

Fig. 4 Surface features of the enamel cementum junction (ECJ) (E = enamel, RS = root surface). (A) ‘Cobbled’ (CB) enamel at the ECJ associated with a root surface featuring cementum with extrinsic fibre bundles (EFB) on a lower left third premolar (scale bar = 25 µm). (B) Enamel margin (EM) with enamel tubules (ET) and exposed dentine tubules (DT) on the root surface on a lower right canine (scale bar = 25 µm). (C) Cementum (CE) overlapping enamel on the root surface of an upper right fourth premolar (scale bar = 50 µm).

Individual fibres within these bundles could usually not

and intrinsic fibre cementum was detected throughout the root surface. Extrinsic fibre cementum was com-

be discerned. Fibre bundles were either densely organized (i.e. no space between fibres) or spaced 5–25 µm apart.

posed of bundles of fibres 2–5 µm in diameter (Fig. 5A).

In a tooth fractured post-mortem, projecting extrinsic



Fig. 5 Features of extrinsic and intrinsic fibre cementum, and cementocyte lacunae on root surfaces (EFB = extrinsic fibre bundles, IF = intrinsic fibres, CL = cementocyte lacunae). (A) Intrinsic fibre cementum distributed between projecting extrinsic fibre bundles on a left lower third premolar (scale bar = 25 µm). (B) Cementum surface of a left lower third premolar fractured post-mortem showing extrinsic fibre bundles that can be traced from the cementum dentine junction (CDJ) to the root surface (RS) (scale bar = 25 µm). (C) Patch of remodelling intrinsic fibre cementum on the root surface of an upper right fourth premolar. Cementocyte lacunae are present among intrinsic fibres (scale bar = 25 µm). (D) Cementocyte lacunae among extrinsic and intrinsic fibres on an upper right first molar. Canaliculi can be observed in the base of lacunae (white arrow, scale bar = 10 µm).

fibre bundles could be traced from the CDJ to the root

cementocyte lacunae present between the extrinsic

surface (Fig. 5B). Intrinsic fibres (1–2 µm wide on average) were present among extrinsic fibre bundles (Fig. 5A), and

fibre bundles. Although the number of different types of teeth was limited in this study, the anatomical features described above were observed in all tooth types.

sometimes formed extrinsic-fibre-free ‘patches’, which increased in number towards the root apex (Fig. 5C). Cementocyte lacunae were associated with intrinsic

Anatomy of embedded and sectioned teeth

fibre cementum and their average diameter was 10 µm,

Enamel prisms and the structure of Hunter–Schreger

although some larger lacunae (15–20 µm) were also observed (Fig. 5D). In general, at the cervical root, the cementum was

bands were observed in all 36 embedded and sectioned teeth (Fig. 6A). The average pit floor width of enamel prisms was 5 µm, and the thickness of interpit enamel was

composed of dense extrinsic fibre bundles 2–5 µm in diameter, which was acellular near the ECJ, but had increasing numbers of cementocytes towards the

approximately 1 µm. In 18 (50%) teeth, enamel tubules were visible within 25 µm of the EDJ (Fig. 6B). A layer of prism-free enamel 5–20 µm thick was present on

mid-root. Towards the apex of the root, extrinsic fibre bundles increased in diameter (up to 10 µm) and

the surface of all teeth (Fig. 6C). The buccal and lingual/palatal surfaces of the ECJ were

became less densely packed with intrinsic fibres and

examined in 28 teeth. The enamel and root surface was



examined within an area that extended 250 µm coronally and apically from the ECJ in all specimens. Enamel had edge-to-edge contact with cementum on the buccal sides of 22 (79%) teeth and lingual/palatal sides of 23 (82%) teeth, either abutting cementum (Fig. 7A) or extending as a thin projection to meet cementum (Fig. 7B). Enamel joined exposed dentine on the buccal sides of six (21%) teeth and lingual/palatal sides of five (18%) teeth (Fig. 7C). Within dentine, tubules were 1–2 µm in diameter and spaced 7–10 µm apart. At the CDJ, the branching terminal ends of tubules < 1 µm in diameter were present (Fig. 8A). The granular layer of Tomes was present within dentine deep to the CDJ in all teeth. A region of parallel rows of von Korff fibres was visible within dentine at the EDJ in eight (22%) teeth (Fig. 8B). Extrinsic fibre bundles were present in all teeth at all locations on the root, extending from the CDJ to the root surface (Fig. 8C). Cementocyte lacunae, 7–10 µm in diameter, were incorporated into cementum, increasing in number and density towards towards the apex, from 20–500 20 –500 µm apart near the cervical root to 20–150 µm apart at the root apex. Enamel was significantly thicker at the crown tip compared with the mid-crown enamel and enamel at the ECJ (within 250 µm coronal to the ECJ; P < P < 0.001, Table 3). Enamel at the mid-crown was also significantly thicker than enamel at the ECJ (P (P < 0.001). Cementum thickness increased significantly from the cervical root to the root apex (Table 4). No significant differences were observed between buccal and lingual/ palatal cementum thickness at the ECJ.

Mineralization of feline dental tissues Analysis of grey levels showed significant differences in mineralization between surface crown tip and inner

Fig. 6 Features of enamel in sectioned teeth (EP = enamel prisms, IP = interpit ameloblastic enamel, EDJ = enamel dentine junction). (A) Enamel prisms surrounded by interpit enamel at the EDJ of a lower right canine. Enamel prisms are organized in alternating Hunter–Schreger bands (scale bar = 50 µm). (B) Enamel tubules (ET) at the EDJ of a lower right first molar (scale bar = 50 µm). (C) Prism-free enamel (PFE) at the crown surface of a lower right canine (scale bar = 20 µm).

Table 3 Thickness of enamel at the crown tip, mid-crown, and enamel cementum junction (ECJ, 250 µm coronal of junction) in embedded and sectioned teeth

Location

Number

Mean thickness (SD) (µm)

Crown tip Mid-crown 250 µm coronal of ECJ

29 35 35

297 (103)*† 176 (62)† 55 (22)

*Significantly thicker than enamel at the mid-crown, P < < 0.001. †Significantly thicker than enamel at the ECJ, P < < 0.001. © 2006 The Authors Journal compilation © 2006 Anatomical Society of Great Britain and Ireland


Fig. 7 Features of the enamel cementum junction (ECJ) structure in sectioned teeth (CE = cementum, E = enamel). (A) Edge-to-edge contact between enamel and cementum in a lower left third premolar. (B) Enamel extending as a thin projection to meet cementum in a lower left third premolar. (C) Enamel margin (EM) joining exposed dentine (D) in a lower left canine. Scale bars = 50 µm.


Fig. 8 Features of dentine and cementum in sectioned teeth (E = enamel, D = dentine, CE = cementum, CDJ = cementum dentine junction). (A) Dentine tubules (DT) at the CDJ in a lower left first molar. Fine tubules are present branching off from larger tubules (asterisk and arrow). The granular layer of Tomes (GLT) is present in dentine deep to the CDJ. (B) Von Korff fibres (VKF) of dentine at the enamel dentine junction (EDJ) of the crown tip of a right mandibular canine. (C) Extrinsic fibre bundles (EFB) extending from the CDJ to the root surface (RS), associated with cementocyte lacunae (CL) in a right mandibular fourth premolar. All scale bars = 50 µm.


Table 4 Thickness of cementum at the enamel cementum junction (ECJ, 250 µm apical of junction), cervical root, mid-root and apical root in embedded and sectioned teeth

Table 6 Mineralization of dentine at the crown tip, midcrown, enamel cementum junction (ECJ, 250 µm coronal of junction), cervical root, mid-root and apical root, in embedded and sectioned teeth. Mineralization is represented by mean grey level and standard deviation (SD)

Location

Number

Mean thickness (SD) (µm)

250 µm apical of buccal ECJ 250 µm apical of ligual/palatal ECJ Cervical root Mid-root Apical root

22 20 31 34 27

11.1 (5.5) 12.3 (5.5) 18.3 (13.6)* 79.9 (62.2)*† 286.1 (160.3)*†‡

*Significantly thicker than cementum at the ECJ, P < 0.001. †Significantly thicker than cementum at the cervical root, P < 0.001. ‡Significantly thicker than cementum at the mid-root, P < 0.001.

crown tip enamel with enamel at the EDJ (P < 0.001, Table 5). No significant difference could be detected between crown tip surface enamel and inner crown tip

Location

Number

Mean grey level (SD)

Crown tip dentine Mid-crown dentine Dentine 250 µm coronal of ECJ Cervical root dentine Mid-root dentine Apical root dentine

25 29 27 25 29 21

117 (17.1)* 114 (16.1)† 106 (6.4)‡ 100 (7.4) 120 (21.0)§ 123 (18.1)§

*Significantly higher mineralization than dentine at the ECJ, P < 0.001. †Significantly higher mineralization than dentine at the ECJ, P < 0.05. ‡Significantly higher mineralization than dentine at the cervic al root, P < 0.05. §Significantly higher mineralization than dentine at the ECJ and cervical root, P < 0.001.

enamel. At the mid-crown, a significant difference (P < 0.05) in mineralization was detected between the surface enamel and enamel at the EDJ. However, no significant difference was observed between mean crown tip enamel mineralization (including surface, inner and junctional enamel) and that of the mean mid-crown (including surface and junctional enamel). The mineralization of both the mean crown tip and the mean mid-crown enamel was significantly higher than the mineralization of enamel at the ECJ (P < 0.001).

dentine at the ECJ (P < 0.001 and 0.05, respectively, Table 6). The dentine at the cervical root had the lowest mineralization of all regions of the tooth. The dentine at the ECJ was significantly more mineralized than the dentine at the cervical root (P < 0.05). However, the dentine at the mid-root and root apex was significantly more mineralized than the dentine at the ECJ and cervical root (P < 0.001). There was no significant difference in mineralization of cementum at any site on the root

There was no significant difference between crown

(Table 7). Cementum mineralization could not be ana-

tip and mid-crown dentine mineralization, although both were found to be significantly higher than the

lysed quantitatively at the ECJ as it was too thin to be measured at this site.

Location Crown tip

Mid-crown

250 µm coronal to ECJ

Surface Inner Enamel dentine junction (EDJ) Mean Surface Enamel dentine junction (EDJ) Mean Mean

Number


26 24 27 22 27 27 27 28

180 (6.7)* 182 (4.0)* 174 (6.7) 179 (4.5)‡ 181 (6.4)† 176 (9.2) 178 (5.5)‡ 173 (4.4)

Table 5 Mineralization of the crown tip, mid-crown and enamel cementum junction (ECJ, 250 µm coronal of junction) enamel in embedded and sectioned teeth. Mineralization is represented by the mean grey level and standard deviation (SD)

*Significantly higher mineralization compared with enamel at the crown tip EDJ, P < 0.001. †Significantly higher mineralization compared with enamel at the mid-crown EDJ, P < 0.05. ‡Significantly higher mineralization compared with enamel at the ECJ. © 2006 The Authors Journal compilation © 2006 Anatomical Society of Great Britain and Ireland


Table 7 Mineralization of cementum at the cervical root, mid-root and root apex in embedded and sectioned teeth. Mineralization is represented by mean grey level and standard deviation (SD)

Location Cervical root Mid-root

Apical root

Cementum dentine junction (CDJ) Surface cementum Mean Cementum dentine junction (CDJ) Surface cementum Mean

Number


13 14 15 22 18 18 21

117 (12.3) 116 (4.3) 122 (15.8) 118 (9.7) 121 (13.5) 122 (12.1) 122 (10.0)

Discussion

expose underlying enamel prisms. The presence of exposed ‘pockets’ of cobbled enamel in the fissures of

An advantage of SEM compared with conventional histology is that it does not require demineralization of tissues, and allows the direct study of mineralized

crowns and near the ECJ that were not associated with wear has not been described in previous studies of cat tooth enamel. The cellular process associated with the

tissue surfaces. Previously, SEM has been used in studies of cat teeth to study enamel development (Boyde,

formation of this feature is unclear, but it may be the result of premature termination of enamel matrix

1964, 1969a,b), to measure the elemental composition

secretion by ameloblasts. At cusp infoldings, adjacent

of enamel, dentine and cementum (Colley et al. 2002), and to describe FORLs (Berger et al. 1996b; Gauthier

populations of ameloblasts may converge and ‘strangulate’ due to space constraints and competition for

et al. 2001; DeLaurier et al. 2005). In the present study,

nutrients from adjacent blood vessels, resulting in a

several features of teeth have been described which

lack of maturation of enamel prisms and failure to

are consistent with previous descriptions of cat teeth made using other imaging methods. However, we have

form a smooth enamel layer (Boyde, 1989). Several previously unreported patterns of organiza-

identified other structural features of cat teeth that

tion of the enamel margin and root surface were

have not been previously reported but may be significant for understanding FORLs.

observed at the ECJ. A ‘cobbled’ enamel margin was frequently observed, but from the surface study it was

Surface enamel was primarily smooth, lacking evidence of perikymata (incremental growth lines) and

unclear whether ‘cobbles’ represented a pattern of terminal-phase enamel secretion by ameloblasts form-

surface prisms, consistent with observations made in

ing spherical structures, or a thin layer of smooth

the cat and dog by Skobe et al. (1985). This prism-free layer was also observed in embedded and sectioned

enamel overlying dentine calcospherites. The presence of a thin enamel layer overlying dentine was confirmed

teeth, overlying the deeper prismatic enamel. This

in the study of sectioned teeth, suggesting ‘cobbles’

smooth surface is formed as a result of slowed incre-

represent enamel overlying dentine globules.

mental growth of enamel prisms by ameloblasts, which is associated with a change in the shape of the Tomes

In tooth surfaces examined, the predominant pattern of the ECJ was of a gap between enamel and cementum

process, resulting in a lack of distinction between pit-

(present in 68% of teeth), followed by edge-to-edge

floor and interpit enamel (Boyde, 1989). The absence of perikymata in the cat reflects rapid growth of the

contact between enamel and cementum (32%). In sectioned teeth, the predominant ECJ patterns were of

crown. In section, the average diameter of enamel prisms was 5 µm, which is consistent with the diameter of prisms described in humans and in dogs, and in pre-

edge-to-edge contact between enamel and cementum (present in 79% buccal and 82% lingual/palatal sides of teeth), and a gap between enamel and cementum

vious studies of the cat (Boyde & Reith, 1968; Boyde, 1969a, 1989; Skobe et al. 1985; Boyde et al. 1988).

exposing dentine (present in 21% buccal and 18% lingual/palatal sides of teeth). In teeth where the surface

The high prevalence of exposed enamel prisms on

of the root was studied, only one tooth (4%) showed

occlusal surfaces and bulbous parts of the crown asso-

cementum overlapping enamel, while in sectioned

ciated with wear marks suggests that the smooth enamel is normally worn away throughout life to

teeth, no specimens featured cementum overlapping enamel at the ECJ. This contrasts with observations of



the ECJ in humans, in which SEM analysis of the entire circumference of the ECJ revealed that edge-to-edge contact between enamel and cementum, and cementum

and morphology (Boyde & Reith, 1983a,b). These cells remain upon the surface of enamel at the ECJ for a shorter period than they do on the surface of crown

overlapping enamel are the predominant patterns, while exposed dentine is least frequently observed (Schroeder & Scherle, 1988). Differences in the distribu-

enamel, which forms earlier. This could lead to enamel being less mineralized at the ECJ. This, combined with low mineralization of dentine, could be related to

tions of ECJ patterns between the surface and section

resorption of the ECJ in FORLs (Reichart et al. 1984;

analyses in the present study are probably due to variations in sampling, as teeth from the same cats

Gauthier et al. 2001; Roes & Mollenbeck, 2003; DeLaurier et al. 2005). It has previously been shown through in

were not used for both analyses.

vitro studies and analysis of mineralization that there is

Exposed dentine at the erstwhile ECJ on intact root

a relationship between the rate of resorption and the

surfaces and in sectioned teeth was a significant observation of this study. It could be a developmental feature

mineral concentration; less mineralized tissues are resorbed more rapidly (Reid, 1986; Jones et al. 1995; Lu

of teeth, as this pattern has also been described in human teeth not affected by disease (Schroeder & Scherle, 1988). Alternatively, exposed dentine could be the

et al. 1999; Gentzsch et al. 2005). The relationship between the low mineralization of tissues at the ECJ and cervical root compared with other regions of the

result of attachment loss of the periodontal ligament (Grzesik & Narayanan, 2002). Exposed dentine lacking

tooth requires further investigation. Previous analysis of FORLs has demonstrated that

the protective cover of cementum may be at risk of the

resorption also involves root surfaces (Gorrel & Larsson,

destructive activity of odontoclasts. In humans, tooth resorption may be associated with damage or deficiency

2002). However, the surface of the non-resorbed tooth was not examined by Gorrel & Larsson (2002) as the

of cementum (Jones & Boyde, 1988; Malek et al. 2001;

teeth were examined after sectioning. In the present

Bilgin et al. 2004; Coyle et al. 2006). Mineralization of

study we addressed this by analysing the surface ana-

dentine was found to be lower than that of adjacent cementum, and its mineralization is lower at the cervical

tomy and have shown that the organization and composition of cementum fibres varies across the root.

root and at the ECJ compared with other areas of the

Extrinsic fibre bundle diameters were within the range

tooth. If dentine is exposed to active odontoclasts, it may be at risk of an increased rate of resorption

described for humans, although the average diameter of bundles in the cat (2–5 µm) is lower than in humans

compared with a root surface where the cementum covering the tooth is present.

(5–7 µm) (Jones & Boyde, 1972). Extrinsic fibre bundle diameter has been previously described in the tiger to

Analysis of enamel thickness showed a significant

be 4–7 µm (Jones, 1973). Feline cementocyte lacunae

decrease from the crown tip to the ECJ, consistent with previous findings using light microscopy (Crossley, 1995).

were within the size range of lacunae observed in human cementum (Jones, 1981). Features of root cementum in

Mineralization of dentine was lowest at the cervical

sectioned teeth were consistent with surface findings,

root and ECJ while the crown tip dentine did not have

including evidence of dense extrinsic fibre bundles and

a significantly higher mineralization compared with mid-crown dentine. This is consistent with previous

cementocytes embedded in cementum matrix. The size and arrangement of extrinsic fibre bundles varied by

observations from microindentation and mineral

location on the tooth surface of the cat and, as in

composition analysis of feline teeth (Sasaki et al. 1984; Hayashi & Kiba, 1989).

humans, the organization of extrinsic fibre bundles in cementum is probably associated with an adaptation

The underlying reason for lower mineralization of enamel and dentine at the ECJ and cervical root is unclear. Reduced mineralization of enamel may be a

of the periodontal ligament fibres to organize along lines of mechanical force (Hassell, 1993). In the cat, extrinsic fibre bundles were generally dense and small

developmental feature, as enamel at the ECJ, which is the last to be formed in the tooth, undergoes a shorter

at the cervical root, becoming larger, more widely spaced, organized in rows, and associated with more

period of maturation–mineralization compared with

cellular intrinsic fibre cementum towards the apex. This

the rest of the crown. Enamel maturation is primarily

is consistent with the pattern in humans where small,

controlled by a small population of maturation-stage ameloblasts that undergo cyclical changes in function

dense fibres orientated perpendicular to the root surface at the cervical root are associated with opposing



lateral compressive forces and protecting deeper periodontal ligament (Hassell, 1993). In the cat, as in other carnivores, the periodontal fibres have been described

might contribute towards understanding why cats are uniquely predisposed to tooth resorption. In conclusion, this study provides a detailed SEM

previously as numerous, dense and orientated obliquely to the root surface. Their attachment to the tooth is more apical than their attachment to alveolar bone

analysis of the microscopic anatomy of adult feline teeth, and of the relative mineralization of enamel, cementum and dentine using quantitative backscattered SEM.

and is adapted to stabilizing the tooth under heavy

Analysis of the ECJ revealed thin enamel and cemen-

loads (Forsberg et al. 1969). We also found that cementum was significantly

tum and exposed dentine at this site. Furthermore, enamel mineralization decreased from the crown tip to

thinner at the ECJ than at the root apex. These findings

the ECJ, and dentine mineralization was lowest at the

support observations made in the tooth surface SEM

ECJ and cervical root. These results indicate that the ECJ

study that remodelling of the root, associated with greater thickening of cementum, increases towards the

and cervical dentine may be at a greater risk of destruction by odontoclasts compared with other regions of

apex. This pattern of cementum thickening towards the root apex has previously been described as a normal feature of feline and human teeth (Forsberg et al. 1969;

the tooth in FORLs. The relationship between these features with FORLs requires further study.

Bilgin et al. 2004). The relationship between cementum thickness and resorption could not be addressed in this

Acknowledgements

study, but thin cementum, like thin enamel, may be at

We would like to thank Sheila J. Jones, for assistance

greater risk of removal by odontoclasts compared with elsewhere on the tooth. For example, cementum

with interpreting the surface SEM data, Peter Howell for help with the analysis of mineralization, and Mo

thinness will determine how quickly odontoclasts

Arora for help with preparation of specimens – all from

reach underlying, less mineralized dentine. Because

the Department of Anatomy, UCL. This work formed

dentine may be resorbed faster than cementum, this may lead to the more rapid progression of FORLs in

part of a PhD thesis awarded to A.D. (University of London 2003). All SEM studies were performed in the

this region.

Department of Anatomy, UCL. The facility for the

Interestingly, there was no significant difference in mineralization of cementum between the CDJ and the

determination of mineralization density at the microscopic scale was provided by the MRC.

surface, and between different locations on the root, which suggests that formation and mineralization of cementum occurs uniformly in feline teeth. In many teeth, cellular intrinsic fibre ‘patches’ were observed on the root surface, which indicate active remodelling and repair of the root by cementoblasts. Inter-individual variation was not explored in this study, nor were the effects of age on root remodelling and the structure of the ECJ. However, these variables merit future study as it has been suggested that the susceptibility to root resorption varies among cats and there is an increased risk of the condition with age (Schlup, 1982; Harvey, 1992; van Wessum et al. 1992; Gengler et al. 1995; Lund et al. 1998; Ingham et al. 2001). Furthermore, an analysis of the anatomical variation between tooth types would be a valuable contribution towards understanding why some teeth are more predisposed to resorption than others (Schlup, 1982; Coles, 1990; Harvey, 1992; van Wessum et al. 1992; Lund et al. 1998; Ingham et al. 2001; Harvey et al. 2004). Analysis of mineralization of teeth among different species © 2006 The Authors Journal compilation © 2006 Anatomical Society of Great Britain and Ireland

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Lyon KF (1992) Subgingival odontoclastic resorptive lesions: classification, treatment, and results in 58 cats. Vet Clin North Am Small Anim Pract 22, 1417–1432. Malek S, Darendeliler MA, Swain MV (2001) Physical properties of root cementum: Part I. A new method for 3-dimensional evaluation. Am J Orthod Dentofacial Orthop 120, 198–208. Mendoza KA, Marretta SM, Klippert LS (2000) Odontoclastic resorptive lesion of a mandibular right first molar in a cougar. J Vet Dent 17, 173–176. Mollenbeck S (2004) Histologic studies about premature changes of feline odontoclastic resorptive lesions (FORL) in clinically healthy teeth. Prakt Tierarzt 85, 174–181. Moody GH, Muir KF (1991) Multiple idiopathic root resorption. A case report and discussion of pathogenesis. J Clin Periodontol 18, 577–580. Nalbandian J, Frank RM (1980) Electron microscopic study of the regeneration of cementum and periodontal connective tissue attachment in the cat. J Periodontal Res 15, 71–89. Nanci A, McKee MD, Smith CE (1992) Immunolocalization of enamel proteins during amelogenesis in the cat. Anat Rec 233, 335–349. Ohba S, Kiba H, Kuwabara M, Yoshida H, Koide F, Takeishi M (1993) Contact microradiographic analysis of feline tooth resorptive lesions. J Vet Med Sci 55, 329–332. Okuda A, Harvey CE (1992) Etiopathogenesis of feline dental resorptive lesions. Vet Clin North Am Small Anim Pract 22, 1385–1404. Okuda A, Asari M, Harvey CE (1995) Challenges in treatment of external odontoclastic resorptive lesions in cats. Comp Cont Educ Pract Vet 17, 1461–1469. Orsini P, Hennet P (1992) Anatomy of the mouth and teeth of the cat. Vet Clin North Am Small Anim Pract 22, 1265–1277. Postlethwaite KR, Hamilton M (1989) Multiple idiopathic external root resorption. Oral Surg Oral Med Oral Pathol 68, 640–643. Reichart PA, Durr UM, Triadan H, Vickendey G (1984) Periodontal disease in the domestic cat. A histopathologic study. J Periodontal Res 19, 67–75. Reid SA (1986) Effect of mineral content of human bon e on in vitro resorption. Anat Embryol (Berl) 174, 225–234.


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The WALTHAM International Nutritional Sciences Symposia

Influence of Diet on Oral Health in Cats and Dogs 1–3 Jerzy P. Gawor,*y4 Alexander M. Reiter,** Katarzyna Jodkowska,*z Grzegorz Kurski,*yy Marek P. Wojtacki,zz and Anna Kurekz Dental Working Group of the Polish Small Animal Veterinary Association (PSAVA), Lublin, Poland; yArka ´w, Poland; University of Pennsylvania School of Veterinary Medicine, Philadelphia, Veterinary Clinic, Krako z ´wna Gospodarstwa Wiejskiego, Warsaw Agricultural University, Warszawa, Poland; yyElwet PA; Szkoła Gło Veterinary Hospital, Warszawa, Poland; and zzIams, Procter & Gamble, Warszawa, Poland *

**

EXPANDED ABSTRACT KEY WORDS:



cats



dogs



diet



oral health



periodontal disease



pet smile campaign

D o w n l MATERIALS AND METHODS o a d In 2003 and 2004, members of the Dental Working Group of the e d Polish Small Animal Veterinary Association (PSAVA) and represen- f r tatives of IAMS Poland recruited veterinary practices to provide oral o m examinations in cats and dogs. The examination procedure consisted j n .n of 3 parts: 3 min of dental/periodontal examination in the patient u t while awake, 3 min of interview and filling in a questionnaire with the r i i o owner, and 3 min of presentation of diagnosis to the owner, instruction t n . on home oral hygiene methods, and recommendations for professional o r treatment. Parameters were recorded and scored, utilizing standard- g b ized charts, and included the age of the patients, type of diet fed [dry, y mixed (dry and soft), or soft food; home-made foods were classified as g u soft food], size of mandibular lymph nodes on palpation, presence of e s dental deposits, and presence of periodontal disease (Table 1). Gender t o n and breed of the patients and extent of home oral hygiene were also O assessed, but the results of these parameters are not reported here. c t o The size of mandibularlymph nodes was determined as being normal, b e slightly enlarged, or moderately to severely enlarged. The presence of r 1 dental deposits was determined visually for the most severely affected ,7 2 tooth and was recorded as follows: absent, up to 50% of the crown 0 1 affected, or .50% of the crown affected. The presence of periodontal 6

The oral cavity in cats and dogs is commonly affected by pathology (1–4), with periodontal disease most frequently recognized (2,5–8). Although changes in feeding methods have arguably improved the health of cats and dogs by reducing or preventing diseases associated with nutritional deficiencies and excesses, periodontal disease remains a serious problem. Numerous studies showed an influence of diet and home oral hygiene on periodontal health (9–16). There is reasonable evidence that soft diets are associated with increased frequency and severity of periodontal disease, and that harder foods requiring vigorous prehension and mastication are preferable for cats and dogs (17). Poland has ;8.5 million dogs and cats; however, its pet food industry is a relatively young market and is estimated to reach ;10% of domestic pets (18,19). The pet owners’ low awareness of consequences of malnutrition on general health and economic aspects may play a role in the continued popularity of home-made foods. The so-called ‘‘Pet Smile Campaign’’ (PSC), conducted previously in the United Kingdom in 1996, was an attempt to enhance oral health awareness and to promote home oral hygiene in cats and dogs. The present study was undertaken to assess parameters related to oral health, dietary management, and home oral hygiene and to further elucidate the relation of diet and periodontal disease in a large feline and canine sample population.

1 Published in a supplement to The Journal of Nutrition . Presented as part of The WALTHAM International Nutritional Sciences Symposium: Innovations in Companion Animal Nutrition held in Washington, DC, September 15–18, 2005. This conference was supported by The WALTHAM Centre for Pet Nutrition and organized in collaboration with the University of California, Davis, and Cornell University. This publication was supported by The WALTHAM Centre for Pet Nutrition. Guest editors for this symposium were D’Ann Finley, Francis A. Kallfelz, James G. Morris, and Quinton R. Rogers. Guest editor disclosure: expenses for the editors to travel to the symposium and honoraria were paid by The WALTHAM Centre for Pet Nutrition. 2 Author disclosure: no relationships to disclose. 3 IAMS Poland supported the study as a sponsor. 4 To whom correspondence should be addressed. E-mail: [email protected].

disease was determined visually for the most severely affected tooth. Gingivitis was recorded when there was inflammation of gingival tissue, which was determined as abnormal reddening or bleeding of the gums. Periodontitis was recorded when a tooth had gingival recession or was mobile on digital palpation. In addition to hands-on training, a free brochure (20) was distributed to all PSC participants, providing detailed instructions on the oral examination and filling in the questionnaire. The oral health index was defined as thesummationof scores obtained for the 3 parameters lymphadenopathy, dental deposits, and periodontal disease, with 0 points indicating optimal oral health, and 6 points indicating poorest oral health. A 1-way analysis of covariance (ANCOVA) was performed to adjust for age. Significance was defined as P , 0.05. Statistical analysis was performed using SPSS 12.0 software.

RESULTS

Complete data were obtained for 9074 cats and 29,702 dogs from 730 Polish veterinary practices ( Table 2 and 3 ): 33.7% of cats and 22.5% of dogs were fed dry food only, 57.4% of cats

0022-3166/06 $8.00  2006 American Society for Nutrition. J. Nutr. 136: 2021S–2023S, 2006.

2021S

2022S

SUPPLEMENT

TABLE 1 Oral health parameters assessed during patient examination 1 Score Parameter

0

Size of mandibular lymph nodes on palpation Presence of dental deposits (plaque, calculus and stain) Presence of periodontal disease

1

2

Normal

Slightly enlarged

Absent

50% of the dental crown affected Gingivitis

Absent

#

Moderately to severely enlarged .50% of the dental crown affected Periodontitis

1 The summation of scores obtained for the 3 parameters provide the oral health index; 0 points indicate optimal oral health, 6 points indicate poorest oral health.

and 57.7% of dogs received both dry and soft food, and 8.9% of cats and 19.8% of dogs were fed soft food only. The mean age of cats and dogs fed dry food or mixed food was significantly lower than the mean age of cats and dogs fed soft food. Although the mean ages of cats fed dry food and those fed mixed food did not differ, the mean age of dogs fed dry food was significantly lower than the mean age of dogs fed mixed food. Lymphadenopathy (80.8 vs. 42.4%), dental deposits (46.0 vs. 14.2%), and periodontal disease (69.7 vs. 33.2%) were significantly more often absent in cats fed dry food, compared with cats fed soft food. Differences in these parameters between cats fed mixed food and those fed soft food were also significant. Lymphadenopathy (81.9 vs. 54.8%), dental deposits (44.3 vs. 17.2%), and periodontal disease (77.8 vs. 45.3%) were significantly more often absent in dogs fed dry food, compared with dogs fed soft food. Differences in these parameters between dogs fed mixed food and dogs fed soft food were also significant. The mean oral health index increased with age in both cats and dogs (Table 4). Even after adjustment of this index for age, the mean oral health index was significantly higher in cats and dogs fed soft food than in cats and dogs fed dry or mixed food. The mean oral health index also was significantly higher in cats and dogs fed mixed food compared with cats and dogs fed dry food (Table 5).

DISCUSSION

Diet management and home oral hygiene are considered important factors that influence periodontal health (5–7,9– 16,21). The present study was conducted on a total of 38,776 animals. Oral examination of such a large number of cats and dogs was limited to a few standardized parameters (21–27).

The size of the mandibular lymph nodes on palpation, the presence of dental deposits, and the presence of periodontal disease were determined. Objectivity was enhanced by hands-on training and step-by-step instructions provided to all participating veterinarians. It is acknowledged that periodontal examination in the present studywas not in depth and not complete. The examining veterinarians evaluated the most severely affected teeth in nonanesthetized patients by visual examination. Plaque index, gingival index, and malodor are difficult to evaluate without anesthesia, appropriate instruments, and adequately trained personnel (3,12,22,23,25,26). Assessment of dietary management was limited to whether the food was dry, mixed (dry and soft), or soft. Other parameters such as the size and texture of kibbles and frequency of feedings were not evaluated. Over 90% of cats and .80% of dogs in the present study were fed dry or mixed food. This is in sharp contrast to previous data that estimated the rate of commercial dry food fed to Polish cats and dogs at 9% (19). Lymphadenopathy, dental deposits, and periodontal disease were absent significantly more often in cats and dogs fed dry food compared with those fed mixed food. Differences in these parameters between cats and dogs fed mixed food and cats and dogs fed soft food were also significant. The mean age of cats and dogs fed dry or mixed food was significantly lower than the mean age of cats and dogs fed soft food. The mean oral health index, and thus the severity of disease, increased with age in both cats and dogs. One might argue that older cats and dogs naturally have worse oral health and therefore prefer soft food over dry food. Therefore, a 1-way ANCOVA was performed to adjust for age. Even after adjustment for age, the mean oral health index was significantly higher in cats and dogs fed soft food compared with those fed dry or mixed food, and the mean oral health index was significantly higher in cats and dogs fed mixed food than in

TABLE 2 Association of diet with oral health in cats 1 Diet Oral health

No lymphadenopathy No dental deposits No periodontal disease 1

Dry food

Mixed food

Soft food

n

%

n

%

n

%

2471 1407 2131

80.8* 46.0* 69.7*

3666 1474 2870

70.4* 28.3* 55.1*

343 115 268

42.4 14.2 33.2

n ¼ 9074 cats (23.4% of surveyed population). Dry food group was comprised of 3058 cats; 33.7% of total; mean age ¼ 4.55 6 3.27 y. Mixed food group was comprised of 5208 cats; 57.4% of total; mean age ¼ 4.72 6 3.38 y. Soft food group was comprised of 808 cats; 8.9% of total; mean age ¼ 6.03 6 3.78 y. This group was significantly older than the other 2 groups. n ¼ number of cats affected; % ¼ percentage frequency of occurrence. *Different from cats fed soft food.

D o w n l o a d e d f r o m j n .n u t r i t i o n . o r g b y g u e s t o n O c t o b e r 1 7 , 2 0 1 6

INFLUENCE OF DIET ON ORAL HEALTH IN CATS AND DOGS

2023S

TABLE 3 Association of diet with oral health in dogs 1 Diet Oral health

Dry food

No lymphadenopathy No dental deposits No periodontal disease

Mixed food

Soft food

n

%

n

%

n

%

5473 2961 5199

81.9* 44.3* 77.8*

12,099 4422 10,900

70.6* 25.8* 63.6*

3223 1012 2664

54.8 17.2 45.3

1 n ¼ 29,702 dogs (76.6% of surveyed population). Dry food group was comprised of 6683 dogs; 22.5% of total; mean age ¼ 5.05 6 3.52 y. Mixed food group was comprised of 17,138 dogs; 57.7% of total; mean age ¼ 5.89 6 3.73 y. Soft food group was comprised of 5881 dogs; 19.8% of total; mean age ¼ 7.06 6 3.96 y. This group was significantly older than the other 2 groups. n ¼ the number of dogs affected; % ¼ the percentage frequency of occurrence. *Different from dogs fed soft food.

TABLE 4

TABLE 5

Association of age with oral health in cats and dogs 1

Mean oral health index adjusted for age in cats and dogs 1

Age Cats

Dogs

,8 mo 8 mo to ,3 y 3 y to ,9 y $9 y ,8 mo 8mo to ,3 y 3 y to ,9 y $9 y

n

%

Oral health index

181 2632 4900 1361

2 29 54 15

0.122 0.712 1.870 3.148

6

891 6237 15148 7426

3 21 51 25

0.126 0.615 1.684 2.965

6

6 6 6

6 6 6

0.029 0.020 0.021 0.045 0.014 0.011 0.011 0.019

1 Values are means 6 SE. n ¼ number of animals affected; % ¼ the percentage frequency of occurrence. Oral health index is the summation of scores obtained for 3 parameters (lymphadenopathy, dental deposits, and periodontal disease); 0 points indicate optimal oral health, 6 points indicate poorest oral health.

those fed dry food. These results indicate that feeding a dry food diet has a positive influence on oral health, decreasing the occurrence of mandibular lymphadenopathy, dental deposits, and periodontal disease in cats and dogs.

LITERATURE CITED 1. Bell AF. Dental disease in the dog. J Small Anim Pract. 1965;6:421–28. 2. Harvey CE, Emily PP. Periodontal disease, small animal dentistry. St Louis: Mosby-Year Book; 1993. p. 89–144. 3. Burrows CF, Miller WH, Harvey CE. Oral medicine. In: Harvey CE, editor. Veterinary dentistry. Philadelphia: WB Saunders Co; 1985. p. 23–33. 4. National Companion Animal Study. University of Minnesota Center for Companion Animal Health; 1996. p. 3. 5. Lyon KF. Advances in periodontal therapy. What about the basics? J Vet Dent. 1993;10(1):5. 6. Gawor J. Osady naze˛bne u pso´w i koto´w. Patogeneza, poste˛powanie, profilaktyka. [Dental deposits in dogs and cats. Pathogenesis, management and prophylaxis]. Magazyn Weterynaryjny; Wet. 1997;29:171–4. 7. DuPont GA. Prevention of periodontal disease. Vet Clin North Am Small Anim Pract. 1998;28:1129–45. 8. Lund EM, Armstrong PJ, Kirk CA, Kolar LM, Klausner JS. Health status and population characteristics of dogs and cats examined at private veterinary practices in the United States. J Am Vet Med Assoc. 1999;214:1336–41. 9. Gorrel C. Periodontal disease and diet in domestic pets. J Nutr. 1998;128: 2712S–4. 10. Gorrel C, Rawlings JM. The role of tooth-brushing and diet in the maintenance of periodontal health in dogs. J Vet Dent. 1996;13:139–43. 11. Logan EI, Finney O, Hefferren JJ. Effects of a dental food on plaque accumulation and gingival health in dogs. J Vet Dent. 2002;19:15–8. 12. Gorrel C, Bierer TL. Long-term effects of a dental hygiene chew on the periodontal health of dogs. J Vet Dent. 1999;16:109–13.

D o w n Diet Oral health index (adjusted) l o a d e Cats Dry food 1.24 6 0.03a d b Mixed food 1.72 6 0.02 f r c o Soft food 2.37 6 0.06 m j a n Dogs Dry food 1.38 6 0.02 .n b Mixed food 1.70 6 0.01 u t r Soft food 2.12 6 0.02c i t i o n . 1 Values are means 6 SE. The mean oral health index was adjusted o r g for age in years (cats: 4.7013 y; dogs: 5.92 y). Means in a column without b a common superscript letter differ between cats and dogs receiving dry, y g mixed, and soft food, P , 0.01. u e s t o n 13. Harvey CE, Shofer FS, Laster L. Correlation of diet, other chewing O activities and periodontal disease in North American client-owned dogs. J Vet c t o Dent. 1996;13:101–5. b 14. Rawlings JM, Gorrel C, Markwell PJ. Effect of two dietary regimens on e r 1 gingivitis in the dog. J Small Anim Pract. 1997;38:147–51. 7 15. Thyse LFH, Vrieling HE, Dijkshoorn NA, Picavet P, Logan EI. Hill’s , 2 Prescription Diet Feline t/d: results of a field study. Proceedings of the Hill’s 0 1 European Symposium on Oral Care; 2003 Mar 19–21; Amsterdam, The Nether- 6

lands; 2003. p. 60–3. 16. Clarke DE,CameronA. Relationship between diet,dentalcalculusand periodontal disease in domestic and feral cats in Australia. Aust Vet J. 1998;76:690–3. 17. Watson AD. Diet and periodontal disease in dogs and cats. Aust Vet J. 1994;71:313–8. 18. Szarek J. Cz1owiek wobec bezdomnych zwierza˛t Materia1y z I Mie˛dzynarodowej Konferencji Naukowej 2002 May 9–10 [Man and homeless animals. Proceedings of 1st International Conference]; Olsztyn, Uniwersytet Warmin´skoMazurski, Poland; 2002. 19. Pet Ownership Survey, MEMRB International Poland. Sp. z o.o. for Masterfoods Poland; May/June 2004. 20. Gawor J, Jodkowska K, Kurski G. Poste˛powanie z pacjentem stomatologicznym. [Dental patient management. Instructions for veterinarians participating in the Pet Smile Campaign 2003–2004.] PSAVA and FH STOPA, Gdynia, Poland; March 2003. 21. Cleland WP. Nonsurgical periodontal therapy. Clin Tech Small Anim Pract. 2000;15:221–5. 22. Hennet P, Soulard Y, Salesse H. Evaluation of the Boyce & Logan plaque scoring method for the study of plaque accumulation in dogs. Proceedings of the 11th European Congress of Veterinary Dentistry; 2002 Oct 1–2; Granada, Spain; 2002. p. 56–8. 23. Schumacher CB. Charting and the oral examination. J Vet Dent. 1993; 10(3):9–13. 24. Harvey CE. Shape and size of teeth of dogs and cats—relevance to studies of plaque and calculus accumulation. J Vet Dent. 2002;19:186–95. 25. Logan EI, Boyce EN. Oral health assessment in dogs: parameters and methods. J Vet Dent. 1994;11:58–63. Erratum in. J Vet Dent. 1994;11:133. 26. Boyce EN, Logan EI. Oral health assessment in dogs: study design and results. J Vet Dent. 1994;11:64–70. 27. Breuer MM, Cosgrove RS. The relationship between gingivitis and plaque levels. J Periodontol. 1989;60:172–5.

VETERINARY PRACTICE GUIDELINES

2013 AAHA Dental Care Guidelines for Dogs and Cats* Steven E. Holmstrom, DVM, DAVDC, Jan Bellows, DVM, DAVDC, DABVP, Stephen Juriga, DVM, DAVDC, Kate Knutson, DVM, Brook A. Niemiec, DVM, DAVDC, Jeanne Perrone, CVT, VTS (Dentistry)

ABSTRACT Veterinary d entistry is constantly progre ssing. The purpose of th is document is to provide guidelines for the practice o f companion animaldentistryfor theveterinaryprofession. Dental care is necessary to provide optimum health and optimize qualityof life. Untreated diseases of the oral cavity are painful and can contribute to local and systemic diseases. This article includes guidelines for preventive oral health care, client communication, evaluation, dental cleaning, and treatment. In addition, materials and equipment necessary to performa medically appropriate procedure are described.( J Am Anim Hosp Assoc 2013; 49:75– 82. DOI 10.5326/JAAHA-MS-4013)

Introduction

Facility Requirements

Veterinary medical dental care is an essential component of a

Dental procedures result in aerosolized bacteria and particu-

preventive healthcare plan. Quality dental care is necessary to provide

late matter. Using a dedicated space is recommended for non-

optimum health and quality of life. If left untreated, diseases of the

sterile dental procedures. The dedicated dental space must

oral cavity are painful and can contribute to other local or systemic

be separate from the sterile surgical suite and needs to be placed

1,2

diseases.

The purpose of this document is to provide guidelines

in a low-traf �c area. New practices and those planning on re-

for the practice of companion animal dentistry. A list of de �nitions

modeling should incorporate a separate dental suite into the

to enhance the understanding of this article is provided in Table 1.

blueprint.

The dental health care team is obligated to practice within the

Appropriate ventilation and anesthetic scavenging systems

scope of their respective education, training, and experience. It is

must also be used. Low-heat, high-intensity lighting, and equip-

imperative that the dental health care team remains current with

ment for magnifying the target area are required to adequately and

regard to oral care, operative procedures, materials, equipment, and

safely visualize the oral cavity and its structures. The operating

products. The team members must attain appropriate continuing

table must allow for drainage and be constructed of impervious,

education through courses such as those offered by the American

cleanable material.

Animal Hospital Association, the American Veterinary Medical Association, the annual Veterinary Dental Forum, industry and

Materials, Instruments, and Equipment

private facilities; by reading the Journal of Veterinary Dentistry;

As with dental techniques, it is important to keep the dental

and by reading other appropriate journals and medical texts. 3–7

materials up-to-date and veterinarians must be aware of what

From the Animal Dental Clinic, San Carlos, CA (S.H.); All Pets Dental Clinic, Weston, FL (J.B.); Veterinary Dental Center, River Heights Veterinary Hospital, Oswego, IL (S.J.); Pet Crossing Animal Hospital & Dental Clinic, Bloomington, MN (K.K.); California Veterinary Dental Specialties, San Diego, CA (B.N.); and Tampa Bay Veterinary Dentistry, Largo, FL (J.P.).

*This document is intended as a guideline only. Evidence-based support for

Correspondence: [email protected] (S.H.)

specific recommendations has been cited whenever possible and appropriate. Other recommendations are based on practical clinical experience and a consensus of expert opinion. Further research is needed to document some of these recommendations. Because each case is different, veterinarians must base their decisions and actions on the best available scientific evidence, in conjunction with their own expertise, knowledge, and experience.These guidelines are supported by generous educational grants from Hill’s Pet Nutrition, Merial, Ltd., Virbac Animal Health, and PDx BioTech, and are endorsed by the American Veterinary Dental College.

ª

2013 by American Animal Hospital Association

JAAHA.ORG

75

TABLE 1

De�nitions that Pertain to Dental Guidelines* Term

De�nition

Dental chart

A written and graphical representation of the mouth, with adequate space to indicate pathology and procedures (see Table 5 for included items)

Dental prophylaxis

A procedure performed on a healthy mouth that includes oral hygiene care, a complete oral examination, and techniques to prevent disease and to remove plaque and calculus from the teeth above and beneath the gum line before periodontitis has developed

Dentistry

The evaluation, diagnosis, prevention, and/or treatment of abnormalities in the oral cavity, maxillofacial area, and/or associated structures. Nonsurgical, surgical, or related procedures may be included

Endodontics

The treatment and therapy of diseases of the pulp canal system

Exodontia (extraction)

A surgical procedure performed to remove a tooth

Gingivitis

Inflammation of the gingiva without loss of the supporting structure(s) shown with X-ray

Oral surgery

The surgical invasion and manipulation of hard and soft tissue to improve/restore oral health and comfort

Orthodontics

The evaluation and treatment of malpositioned teeth for the purposes of improving occlusion and patient comfort and enhancing the quality of life

Periodontal disease

A disease process that begins with gingivitis and progresses to periodontitis when left untreated

Periodontitis

A destructive process involving the loss of supportive structures of the teeth, including the periodontium, gingiva, periodontal ligament, cementum, and/or alveolar bone

Periodontal surgery

The surgical treatment of periodontal disease. This is indicated for patients with pockets or inaccessible areas

Periodontal therapy

Treatment of tooth-supporting structures where periodontal disease exists. This involves the nonsurgical removal of plaque, calculus, and debris in pockets; and the local application of antimicrobials

Periodontium

The supporting structures of the teeth, including the periodontal ligament, gingiva, cementum, and alveolar and supporting bone

Pocket

A pathologic space between supporting structures and the tooth, extending apically from the normal site of the gingival epithelial attachment

. 5

mm, class II or III furcation exposure,

* Some of these definitions were derived from descriptions in Holmstrom et al . (2004).3

materials are considered appropriate for the treatment of dental

The safety of the operator must be ensured during dental

conditions. Commonly used materials can be found by consulting

procedures by using radiographic, oral, respiratory, skin, eye, and

a dental text and attending continuing education programs pre-

ear protective devices (Table 4). Ergonomic considerations in-

sented by a dental specialist.

clude proper seating, fatigue mats for standing, and proper po-

Instruments and dental equipment require routine and

sitioning of both the patient and materials to minimize immediate

frequent maintenance. Maintenance information can be found

and chronic operator injuries. Provide the operator with in-

in some dental texts and through the manufacturer. Instru-

struction on proper instrument handling techniques.

ments must be sharp and properly stored, and instruments in poor condition need to be replaced. A written protocolneeds to be

Patient Assessment

established and followed for equipment and instrument care.

History and Physical Examination

As with human dentistry, instruments that enter the oral

The history must include prior home dental hygiene delivered by

cavity should be sterilized. Packets organized by dental procedure

the client; diet; access to treats and chews; chewing habits; current

(e.g., examination, extraction, periodontal surgery) should be

and previous dental care and procedures; prior and current dis-

prepared and sterilized before use.

eases, including any behavioral issues and allergies; and medi-

Recommended materials, instruments, and equipment for

cations or supplements currently administered. Perform a physical

performing dental procedures are listed in Tables 2 and 3. Con-

examination of all body systems based on the species, age, health

sult the reference list associated with these guidelines for rec-

status, and temperament of the animal. If the patient is presented

ommendations and information on ordering equipment.3–7

for a complaint not related to dentistry, give due consideration to the primary complaint, performing the diagnostic tests and treatments

Operator Protection

indicated. Establish priorities if multiple procedures are indicated.

Pathogens and debris such as calculus, tooth fragments, and prophy paste are aerosolized during dental procedures. Irrigating

Assessment by Life Stage

the oral cavity with a 0.12% chlorhexidine solution before dental

Focus on age-related dental conditions and common abnormalities

scaling decreases bacterial aerosolization.8

in the dog and cat. From birth to 9 mo of age, evaluate the patient

76 JAAHA

| 49:2 Mar/Apr 2013

Veterinary Practice Guidelines

TABLE 2

TABLE 4

Materials Needed for the Practice of Veterinary Dentistry*

Minimum Protective Devices to be used During Dental Procedures

Necessary materials

· Antiseptic rinse · Prophy paste/pumice · Prophy angle and cups · Hemostatic agents · Sealant · Needles and syringes · Intraoral digital system or radiographic film · Measures to prevent hypothermia (e.g., conductive blanket, hot air blanket, circulating water blanket, towels, blankets) · Gauze and sponges · Antimicrobial agent for local application · Suture material (4-0 and smaller) · Bone augmentation material · Local anesthetic drugs

· Cap or hair bonnet · Mask · Goggles, surgical spectacles, or face shield · Smock · Gloves · Earplugs · Dosimeter · Protection from radiation (e.g., lead shield)

Necessary equipment

In a large-breed dog, periodontal diseases may not start until

· Equipment to expose and process intraoral digital radiograph system or intraoral films Suction · · A high- and low-speed delivery system for air and water · Fiber optic light source · Equipment for sterilizing instruments · Low- and high-speed hand pieces (minimum two of each) · Various sizes of round/diamond and cross cut fissure burrs · Powered scaler with tips for gross and subgingival scaling (ultrasonic, subsonic, or piezoelectric) Head or eye loupes for magnification · * Please note that disposable items are for single use only.

diet, and home dental care. In a small-breed dog without home dental care, periodontal diseases can start as early as 9 mo of age. later. Many small-breed dogs have periodontal diseases by 3 yr of age.9–12 Beyond 2 yr of age, evaluate the progression of periodontal diseases, damage to tooth structures, occurrence of oral masses, and the existence and adequacy of preventive home dental care. As the animal ages, continue to evaluate the patient for progressive periodontal diseases, oral tumors, and other aspects of dental pathology.13

Oral/Dental Examination in the Conscious Patient Record all �ndings in the medical record (Table 5). Evaluate the

for problems related to the deciduous teeth, missing or extra teeth,

head and oral cavity both visually and by palpation. Changes in

swellings, juvenile diseases (such as feline juvenile onset peri-

body weight, eating habits, or other behaviors can indicate dental

odontitis), occlusion, and oral development. From 5 mo to 2 yr of

disease. Speci�c abnormal signs to look for may include pain;

age, evaluate the patient for problems related to developmental

halitosis; drooling; dysphagia; asymmetry; tooth resorption; dis-

anomalies, permanent dentition, and the accumulation of plaque

colored, fractured, mobile, missing, or extra teeth; in�ammation

and calculus. Periodontal diseases may begin during that time

and bleeding; loss of gingiva and bone; and changes in the range

period, especially in cats and small-breed dogs. The onset and

of motion or pain in the temporomandibular joint. In addition,

severity of periodontal diseases varies widely depending on breed,

the practitioner should assess the patient’s occlusion to ensure it is normal, or at least atraumatic. Evaluate the patient ’s eyes, lymph nodes, nose, lips, teeth, mucous membranes, gingiva, vestibule

TABLE 3

Instruments to Include in the Dental Surgical Pack*

· Scalers · Curettes · Probes/explorer · Sharpening materials · Scalpel · Extraction equipment (e.g., periosteal elevators, luxating elevators, periodontal elevators, extraction forceps, root tip picks, root tip forceps) · Thumb forceps · Hemostats · Iris, LaGrange, Mayo, or Metzenbaum scissors · Needle holders · Mouth mirror · Retraction aid (e.g., University of Minnesota retractor) * Instruments must be sterilized by accepted techniques prior to each use. Hand instruments must by properly sharpened and cared for.

(i.e., the area between the gum tissue and cheeks), palatal and lingual surfaces of the mouth, dorsal and ventral aspects of the tongue, tonsils, and salivary glands and ducts. Note all abnormalities such as oral tumors, ulcers, or wounds. A diagnostic test strip for the measurement of dissolved thiol levels can be used as an exam room indicator of gingival health and periodontal status.14 The oral examination performed on a conscious patient allows the practitioner to design a preliminary diagnostic plan. Take into consideration potential patient pain. Do not offend the patient by probing unnecessarily when such manipulations can be better achieved under anesthesia. Also, realize in many instances that the examiner will underestimate the conditions present because it is impossible to visualize all oral structures

JAAHA.ORG

77

compliance. For example, “dental” diets and chews can be used

TABLE 5

until the client is comfortable either brushing or applying an Items to Include in the Dental Chart and/or Medical Record

· Signalment · Physical examination, medical, and dental history findings · Oral examination findings · Anesthesia and surgery monitoring log and surgical findings · Any dental, oral, or other disease(s) currently present in the animal · Abnormal probing depths (described for each affected tooth) · Dentition chart with specific abnormalities noted, such as discoloration; · · · ·

worn areas; missing, malpositioned, or fractured teeth; supernumerary, tooth resorption; and soft-tissue masses Current and future treatment plan, addressing all abnormalities found. This includes information regarding initial decisions, decision-making algorithm, and changes based on subsequent findings Recommendations for home dental care Any recommendations declined by the client Prognosis

antiplaque gel, rinse, or spray with a wipe. The gold standard is brushing the pet’s teeth using a brush with soft bristles either once or twice daily. If the client is either unable or unwilling to persevere with brushing, use any of the other oral hygiene options that the patient will tolerate. Explain the two-part process involved in a diagnostic dental cleaning and patient evaluation to the client. It is critical that he/she understand the hospital protocol to minimize miscommunication and frustration. The procedure involves both an awake component and an anesthetized component for a complete evaluation. It is not until the oral radiographs have been evaluated that a full treatment plan including costs of the anticipated procedure(s) can be successfully made with any degree of accuracy.

when the patient is awake. It is only when the patient has been

Evaluation of a patient for dental disease involves the awake

anesthetized that a complete and thorough oral evaluation can

procedure as the �rst step. This is where an initial assessment is

be accomplished successfully. The complete examination in-

made. Although many problems may be seen at this point of the

cludes a tooth-by-tooth visual examination, probing, and ra-

evaluation, a thorough diagnosis and treatment plan cannot be

diographic examination. Only then can a precise treatment plan

determined until charting, tooth-by-tooth examination of the

and fees for proposed services be tabulated and discussed with

anesthetized patient, and dental radiographs have been taken

the pet owner(s).

and evaluated. Studies have demonstrated that much of the pathology in a patient’s oral cavity cannot be appreciated until dental

Making Recommendations and Client Education

radiographs are taken and assessed; therefore, have protocols in

Discuss the

informed decision on how they want to proceed with the pro-

�ndings

of the initial examination and additional

diagnostic and/or therapeutic plans with the client. Those plans

place within the practice to give clients ample time to make an posed treatment plan.16

will vary depending on the patient; the initial � ndings; the client’s

Some hospitals may want to do the awake examination and

ability to proceed with the recommendations; as well as the cli-

the anesthetic component (charting, cleaning, and dental radio-

ent’s ability to provide necessary, lifelong plaque prevention.

graphs) as the � rst procedure. They can then stage the treatment

When either an anesthetic examination or procedure is not

plan as a second procedure. This will give the hospital staff ade-

planned in a healthy patient, discuss preventive healthcare, oral

quate time to explain to the client the treatment plan, including

health, and home oral hygiene. Options include brushing and the

giving educational information on the diagnosis, reviewing ra-

use of dentifrices, oral rinses, gels and sprays, water additives, and

diographic

dental diets and chews. Discourage any dental chew or device that

want to perform the treatment plan during the

does not bend or break easily (e.g., bones, cow/horse hooves,

event so everything is done at that procedure. Whichever way the

antlers, hard nylon products). The Veterinary Oral Health Council

hospital chooses, there must be a client communication plan in

lists products that meet its preset standard for the retardation of

place so the client is involved and feels comfortable going forward

15

plaque and calculus accumulation. Illustrate to the owner how to

�ndings,

and going over costs. Other hospitals may �rst

anesthetic

with the proposed treatment plan.

perform oral hygiene, such as brushing, wiping teeth, application

Perform the anesthetized portion of the dental evaluation of

of teeth-coating materials, and the use of oral rinses and gels.

charting, cleaning, and radiographs when abnormalities are seen

Allow the client to practice so they will be able to perform the

on the awake exam (such plaque or tartar at the free gingival

agreed-upon procedure(s) at home.

surface of the maxillary canines or fourth premolars) or at least

All home oral hygiene options, from diet to the gold standard

on an annual basis starting at 1 yr of age for cats and small- to

of brushing, along with any of their potential limitations need to be

medium-breed dogs and at 2 yr of age for large-breed dogs. Details

discussed with the client. It is essential that the oral health medical

on the recommended frequency of examinations are discussed

plan is patient-individualized to attain the greatest level of client

under Progress or Follow-Up Evaluation (below).

78 JAAHA

| 49:2 Mar/Apr 2013


Planning the Dental Cleaning and Patient Evaluation

extubation. Regardless of whether packing is used, the last step

Use well-monitored, inhalation anesthesia with cuffed intubation

make certain no foreign material is left behind. Proper positioning

when performing dental cleanings. Such techniques increase safety,

of the patient by placing them in lateral recumbency can also help

reducestress, decrease thechances of adverse sequelae (e.g., inhalation

prevent aspiration. Provide safe immobilization of the head.

prior to extubation is an examination of the caudal oral cavity to

pneumonia), and are essential for thorough and ef �cient evaluation

If oral surgery is planned, the institution of an intraoral local

and treatment of the patient. Attempting to perform procedures on

anesthetic is warranted in conjunction with the general anesthesia.

an awake patient that is struggling, under sedation, or injectable

This decreases the amount of general anesthetic needed and

anesthesia reduces the ability to make an accurate diagnosis, does not

reduces the amount of systemic pain medication required post-

allow adequate treatment, and increases stress and risks to the patient.

operatively.1,27,33 Local anesthetic blocks can last up to 8 hr, and they decrease hypotension and hypoventilation caused with in-

Prior to Anesthesia

halant anesthetics by reducing the amount of gas needed to

Preoperative evaluation includes a preanesthetic physical exami-

maintain a safe anesthetic plane. 3,6,34,35

nation. It is crucial to follow the most up-to-date recommendations for preoperative laboratory testing based on the patient’s life stage

Dental Procedures

and any existing disease. Preoperative care includes IV catheteri-

The terms prophy , prophylaxis , and dental are often misused in

zation to facilitate administration of IV �uid therapy, preemptive

veterinary medicine. A professional dental cleaning is performed

pain management, and antibiotics (when indicated). Review the

on a patient with plaque and calculus adhered to some of the

most up-to-date guidelines on anesthesia, antimicrobial use, �uid

teeth, but otherwise has an essentially healthy mouth or mild

therapy, feline life stage, canine life stage, preventive healthcare,

gingivitis only. The intent of dental cleaning is to prevent peri-

17–25

pain management, and referral for speci�c recommendations.

odontitis. Patients with existing disease undergo periodontal therapy in addition to professional dental cleaning. Dental pro-

Anesthesia

cedures must be performed by a licensed veterinarian, a creden-

General anesthesia with intubation is necessary to properly assess

tialed technician, or a trained veterinary assistant under the

and treat the companion animal dental patient. It is essential that

supervision of a veterinarian in accordance with state or provin-

aspiration of water and debris by the patient is prevented through

cial practice acts. Practice acts vary from jurisdiction to jurisdic-

endotracheal intubation. Cleaning a companion animal’s teeth

tion, and the veterinarian must be familiar with those laws.

without general anesthesia is considered unacceptable and below

Surgical extractions are to be performed only by trained, licensed

the standard of care. Techniques such as necessary immobilization

veterinarians. All extractions need to have postextraction, in-

without discomfort, periodontal probing, intraoral radiology, and

traoral radiographs. All dental procedures need to be described

the removal of plaque and tartar above and below the gum line

properly (Table 1), and a consistent method should be used to

that ensure patient health and safety cannot be achieved without

record �ndings in the medical record (Table 5).

general anesthesia.

26

Positioning and safety of the patient is important. Manually

During anesthesia, one trained person is dedicated to con-

stabilize the head and neck when forces are being applied in the

tinuously monitoring and recording vital parameters, such as

mouth. Avoid using mouth gags because they can cause myalgia,

body temperature, heart rate and rhythm, respiration, oxygen sat-

neuralgia, and/or trauma to the temporomandibular joint. If a

uration via pulse oximetry, systemic blood pressure, and end-tidal

mouth gag is necessary, do not fully open the mouth or overextend

CO 2 levels q 5 min (or more frequently if sudden changes are

the temporomandibular joint. Never use spring-loaded mouth

27,28

noted).

IV �uid therapy is essential for circulatory mainte-

gags. Do not overin�ate the endotracheal tube. Always disconnect

nance. Customize the type and rate of �uids administered

the endotracheal tube when repositioning the patient to prevent

according to the patient ’s needs.29,30

trauma to the trachea.

Prevention of hypothermia with warming devices is essential because the patient may become wet, and dental procedures can be

Essential Steps for Professional Dental Cleaning

lengthy. 31,32 Additionally, suction and packing the caudal oral

The essential steps for a professional dental cleaning and peri-

cavity with gauze can prevent aspiration and decrease hypother-

odontal therapy are described in the following list:

mia. If packing materials are used, steps must be taken to ensure

1. Perform an oral evaluation, as described above, for the con-

there is no chance of the material being left behind following

scious patient.

JAAHA.ORG

79

2. Radiograph the entire mouth, using either intraoral or digital radiographic systems. Radiographs are necessary for accurate evaluation and diagnosis. In one published report, intraoral radiographs revealed clinically important pathology in 27.8% of dogs and 41.7% of cats when no abnormal �ndings were

13. Take postoperative radiographs to evaluate the treatment applied. This is especially important in extraction cases. 14. Examine and rinse the oral cavity. Remove any packing or foreign debris. 15. Recommend referral to a specialist when the primary veterinary

noted on the initial examination.16 In patients with abnormal

practitioner does not have the skills, knowledge, equipment, or

�ndings,

facilities to perform a speci�c procedure or treatment.

radiography revealed additional pathology in 50% of 16

dogs and 53.9% of cats.

Standard views of the skull are

inadequate when evaluating dental pathology. If full mouth

Postoperative Management

�lms are not

Maintain an open airway via intubation until the animal is either

taken, the client must be informed that they were

not done.

swallowing or in sternal recumbency. Maintain body tempera-

3. Scale the teeth supra- and, most importantly, subgingivally

ture and continue IV

�uid

support as needed. Continuously

using either a hand scaler or appropriate powered device

monitor and record vital signs until the patient is awake. Assess

followed by a hand instrument (i.e., scaler, curette). Do

and record pain scores throughout the recovery period, con-

not use a rotary scaler, which excessively roughens the tooth

tinuing pain management while the pet is in the hospital and

36

upon discharge.34,44

enamel.

4. Polish the teeth using a low-speed hand piece running at no more than 300 revolutions/min with prophy paste that is mea-

Client Education and Follow-up

sured and loaded on a disposable prophy cup for each patient

Postoperative Communication

(to avoid cross-contamination).

Client communication is fundamental to the maintenance of oral

5. Perform subgingival irrigation to remove debris and polishing paste and to inspect the crown and subgingival areas.

health. At the time of discharge, discuss all operative procedures and existing/potential complications (e.g., sedation, vocalization,

6. Apply antiplaque substances, such as sealants.

bleeding, coughing, dehiscence, infection, neurologic signs, hali-

7. Provide instructions to the owner regarding home oral hygiene.

tosis, vomiting, diarrhea, anorexia, signs of pain). Discuss immediate postoperative home oral hygiene, including medications

Additional Steps for Periodontal Therapy and Other Conditions

and their side effects. Provide antibiotics and medication for in�ammation

and pain as indicated. 41,42 Discuss any change in diet

that might be necessary, such as a change to either soft or pre8. Evaluate the patient for abnormal periodontal pocket depths

moistened food or to a prescription dental diet. Also indicate the

using a periodontal probe. The depth that is considered ab-

duration of those changes. Provide individualized oral and written

normal varies depending on the tooth and size of the dog or

instructions at the time of discharge. Establish an appointment for

cat.3,4,6,37 In medium-sized dogs, the probing depth should not

a follow-up examination and further discussion.

be . 2 mm, and in the mid-sized cats, the depth should not be .

Home Oral Hygiene

1 mm.

9. Perform periodontal therapy ( Table 1) based on radiographic �ndings

38–40

and probing.

10. Administer perioperative antibiotics when indicated, either parenterally or locally.41,42

Home oral hygiene is vital for disease control. Telephone the client the day after the procedure to inquire about the pet’s condition, to determine the client’s ability to implement the medication and home oral hygiene plan, to answer questions,

11. Perform periodontal surgery to remove deep debris, elimi-

and address any concerns the client might have. The home oral

nate pockets, and/or extract teeth. When either pockets or

hygiene plan includes the frequency, duration, and method of

gingival recession is . 50% of the root support, extraction or

rinsing and brushing; applying sealants; and the use of dental

periodontal surgery is indicated and should be performed by

diets and dental chews.45 The Veterinary Oral Health Council

trained veterinarians or referred to a specialist.

has a list of products that are reportedly effective in retarding the

12. Biopsy all abnormal masses that are visualized grossly or

accumulation of dental plaque and/or calculus. 46 Some of the

noted on radiographs. Submit all samples for histopathol-

details regarding the home oral hygiene plan might best be left

ogy to be analyzed by a pathologist quali�ed in oral tissues

for discussion with the client at the � rst postoperative follow-up

analysis.43

evaluation.

80 JAAHA

| 49:2 Mar/Apr 2013


Progress or Follow-up Evaluation

options for the optimal care and treatment available for their pets.

With each follow-up examination and telephone communication,

Dentistry is becoming more specialized, and referral to a veterinary

repeat the home dental care instructions and recommendations to

dental specialist or a general practitioner with advanced training and

the client. Set the number and timing of regular follow-up visits

proper equipment is recommended if the necessary expertise and/or

based on the disease severity. Although few studies have been

equipment are unavailable at the primary veterinarian’s of �ce.

performed in dogs and cats, extrapolation from the human literature and guidelines about aging in dogs and cats leads to the following recommendations:14

·

Dental health care needs to be part of the preventive healthcare examination discussion and should begin at the �rst appointment at which the patient is seen and continue routinely throughout subsequent exams.

· Examinations q 6 mo can help ensure optimal home oral hygiene. At a minimum, evaluate animals with a healthy mouth at least q 12 mo.

· Evaluate pets with gingivitis at least q 6 mo. · Evaluate pets with periodontitis at least q 3 6 mo. · Advanced periodontal disease requires examinations q 1 mo –

until the disease is controlled. Evaluate disease status, such as periodontal disease, on the conscious patient with products that allow an assessment of periodontal health without placing the patient under anesthesia. 14 During subsequent examinations, evaluate client compliance, revise the treatment plan as needed, and rede �ne the prognosis.

Nutrition Nutrition plays an important role in oral health; therefore, it is important for the healthcare team to have an understanding of the impact of nutrition on their patients. A properly balanced diet is essential for good general health, including health of oral tissues. For good oral health, it is the form of the diet, not the nutritional content, that is critical for good oral health. A diet that provides mechanical cleansing of the teeth is an excellent way of retarding the accumulation of dental plaque and calculus. Dental diets and chews can be very effective if the owner is unable to brush the teeth. Dental diets work either by “brushing ” the crowns of the teeth as the animal chews or by coating an anticalculus agent on the surface of the teeth. Nutrition becomes even more critical in dental health when the client is unable to provide home oral hygiene by brushing.47 During subsequent examinations, evaluate client compliance, revise the treatment plan as needed, and rede�ne the prognosis.

Conclusion Pets can live more comfortable lives if oral health care is managed and maintained. All members of the veterinary team must strive to increase the quality of dental care delivered. Clients must be given

REFERENCES

1. Beckman BW. Pathophysiology and management of surgical and chronic oral pain in dogs and cats. J Vet Dent 2006;23(1):50 –60. 2. Carpenter RE, Manfra Maretta S. Dental patients. In: Tranquilli WT, Grimm KA, Thurmon J, eds. Lumb and Jones veterinary anesthesia and analgesia. 4th ed. Philadelphia (PA): Wiley-Blackwell; 2007: 993–5. ’

3. Holmstrom SE, Frost-Fitch P, Eisner ER. Veterinary dental techniques for the small animal practitioner . 3rd ed. Philadelphia (PA): WB Saunders; 2004. 4. Holmstrom SE. Veterinary dentistry: a team approach. 2nd ed. St. Louis (MO): Elsevier; 2012. 5. Wiggs RB, Lobprise HB. Veterinary dentistry: principles and practice . Philadelphia (PA): Lippincott-Raven; 1997. 6. Bellows J. Small animal dental equipment, materials and techniques . 1st ed. Ames (IA): Blackwell; 2004. 7. Mulligan T, Aller MS, Williams CA. Atlas of canine and feline dental radiography . Trenton (NJ): Veterinary Learning Systems; 1998. 8. Logothetis DD, Martinez-Welles JM. Reducing bacterial aerosol contamination with a chlorhexidine gluconate pre-rinse. J Am Dent Assoc 1995;126(12):1634–9. 9. Grove TK. Periodontal disease. In: Harvey C, ed. Veterinary dentistry . Philadelphia (PA): WB Saunders; 1985:59–78. 10. Harvey CE, Emily PP. Small animal dentistry . St. Louis (MO): Mosby Year Book; 1993:89–144. 11. Hennet PR, Harvey CE. Natural development of periodontal disease in the dog: a review of clinical, anatomical and histological features. J Vet Dent 1992;9(3):13–9. 12. Harvey CE, Shofer FS, Laster L. Association of age and body weight with periodontal disease in North American dogs. J Vet Dent 1994;11(3):94 –105. 13. Niemiec BA. Systemic manifestations of periodontal disease. In: Niemiec BA, ed. Veterinary periodontology . Ames (IA): Wiley-Blackwell; 2012:81 –90. 14. Manfra Marretta S, Leesman M, Burgess-Cassler A, et al. Pilot evaluation of a novel test strip for the assessment of dissolved thiol levels, as an indicator of canine gingival health and periodontal status. Can Vet J 2012:1260. 15. Veterinary Oral Health Council. Available at: www.vohc.com. Accessed January 24, 2013. 16. Verstraete FJ, Kass PH, Terpak CH. Diagnostic value of full-mouth radiography in cats. Am J Vet Res 1998;59(6):692–5. 17. Epstein M, Kuehn N, Landsberg G, et al. AAHA senior care guidelines for dogs and cats. J Am Anim Hosp Assoc 2005;41(2): 81–91. Available at: www.aahanet.org/Library/Guidelines.aspx . Accessed January 24, 2013. 18. Bednarski R, Grimm K, Harvey R, et al. AAHA anesthesia guidelines for dogs and cats. J Am Anim Hosp Assoc 2011;47(6):377–85. Available at: www.aahanet.org/Library/Guidelines.aspx . Accessed January 24, 2013.

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19. AAHA/AAFP Basic guidelines of judicious therapeutic use of antimicrobials. Available at: www.aahanet.org/Library/Guidelines.aspx . Accessed January 24, 2013.

34. Tranquilli WJ, Grimm KA, Lamont LA. Pain management for the small animal practitioner . Jackson (WY): Teton New Media; 2000: 13–30.

20. Bartges J, Boynton B, Vogt AH, et al. AAHA canine life stages guidelines. J Am Anim Hosp Assoc 2012;48(1):1–11. Available at: www. aahanet.org/Library/Guidelines.aspx . Accessed January 24, 2013.

35. Lantz GC. Regional anesthesia for dentistry and oral surgery. J Vet Dent 2003;20(3):181–6.

21. Hoyumpa Vogt A, Rodan I, Brown M, et al. AAFP-AAHA feline life stages guidelines. J Feline Med 378 Surg 2010;12(1):43 –54. Available at: www.aahanet.org/Library/Guidelines.aspx . Accessed January 379 24, 2013. 22. AAHA/AAFP Fluid Therapy Guidelines. 2013. In press. 23. Hellyer P, Rodan I, Brunt J, et al. AAHA/AAFP pain management guidelines for dogs and cats. J Am Anim Hosp Assoc 2007;43(5): 235–48. Available at: www.aahanet.org/Library/Guidelines.aspx . Accessed January 24, 2013. 24. Development of new canine and feline preventive healthcare guidelines designed to improve pet health. American Animal Hospital Association-American Veterinary Medical Association Preventive Healthcare Guidelines Task Force. J Am Anim Hosp Assoc. 2011 Sep-Oct;47(5):306–11. 25. AAHA referral guidelines. Available at: www.aahanet.org/Library/ Guidelines.aspx . Accessed January 24, 2013. 26. American Veterinary Dental College. American Veterinary Dental College position statement: companion animal dental scaling without anesthesia. Available at: http://avdc.org/Dental_ Scaling_Without_Anesthesia.pdf . Accessed January 24, 2013. 27. Pascoe P. Anesthesia and pain management. In: Verstraete F, Lommer M, eds. Oral and maxillofacial surgery in dogs and cats . WB Saunders; 2012:26–7. 28. Stepaniuk K, Brock N. Anesthesia monitoring in the dental and oral surgery patient. J Vet Dent 2008;25(2):143–9. 29. Thurmon JC, et al. Acid-base balance and �uid therapy. In: Essentials of small animal anesthesia and analgesia. Philadelphia: Lippincott, Williams & Wilkins; 1999:339 –74. 30. Seeler D. Fluid, electrolyte, and blood component therapy. In: Veterinary Anesthesia and Analgesia. Blackwell Publishing; 2007:185 –96. 31. Hale FA, Anthony JM. Prevention of hypothermia in cats during routine oral hygiene procedures. Can Vet J 1997;38(5):297–9. 32. Stepaniuk K, Brock N. Hypothermia and thermoregulation during anesthesia for the dental and oral surgery patient. J Vet Dent 2008;25 (4):279–83. 33. Chapman PJ, Ganendran A. Prolonged analgesia following preoperative bupivacaine neural blockade for oral surgery performed under general anesthesia. J Oral Maxillofac Surg 1987;45(3):233 –5.

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36. Brine EJ, Marretta SM, Pijanowski GJ, et al. Comparison of the effects of four different power scalers on enamel tooth surface in the dog. J Vet Dent 2000;17(1):17 –21. 37. Niemiec BA. Veterinary periodontology . Ames (IA): Wiley-Blackwell; 2012. 38. Beckman BW. Patient management for periodontal therapy. In: Niemiec BA, ed. Veterinary periodontology . Ames (IA): WileyBlackwell; 2012:305–12. 39. Niemiec BA. Advanced non-surgical therapy. In: Niemiec BA, ed. Veterinary periodontology . Ames (IA): Wiley-Blackwell; 2012: 154–69. 40. Niemiec BA. The complete dental cleaning. In: Niemiec BA, ed. Veterinary periodontology . Ames (IA): Wiley-Blackwell; 2012: 129–53. 41. Hennet P. Periodontal disease and oral microbiology. In: Crossley DA, Penman S, eds. Manual of small animal dentistry . 2nd ed. Shurdington (England): British Small Animal Veterinary Association; 1995:105 –13. 42. Sarkiala E, Harvey C. Systemic antimicrobials in the treatment of periodontitis in dogs. Semin Vet Med Surg (Small Anim) 1993;8(3): 197–203. 43. Huffman LJ. Oral examination. In: Niemiec BA, ed. Small animal dental, oral and maxillofacial disease: a color handbook . London: Manson; 2010:39 –61. 44. Quality of Care. Pain Management . Lakewood (CO): American Animal Hospital Association Standards of Accreditation; 2003. 45. Niemiec BA. Home plaque control. In: Niemiec BA, ed. Veterinary periodontology . Ames (IA): Wiley-Blackwell; 2012:175 –85. 46. Veterinary Oral Health Council. Available at: www.vohc.org/ accepted_products.htm. Accessed January 24, 2013. 47. Jensen L, Logan E, Finney O, et al. Reduction in accumulation of plaque, stain, and calculus in dogs by dietary means. J Vet Dent 1995;12(4):161–3. SUPPLEMENTARY REFERENCES

Bellows J. Feline Dentistry . Ames (IA): Wiley; 2010 Dupont GA, DeBowes LJ. Atlas of dental radiography in dogs and cats . St. Louis (MO): WB Saunders; 2009.

A longitudinal assessment of periodontal disease in 52 miniature schnauzers Marshall et al.

Marshall et al. BMC Veterinary Research 2014, 10 :166 http://www.biomedcentral.com/1746-6148/10/166


RESEARCH ARTICLE

Open Access

A longitudinal assessment of periodontal disease in 52 miniature schnauzers Mark D Marshall 1, Corrin V Wallis 1, Lisa Milella 2, Alison Colyer1, Andrew D Tweedie1 and Stephen Harris1* Abstract Background: Periodontal disease (PD) is the most widespread oral disease in dogs and has been associated with serious systemic diseases. The disease is more prevalent in small breeds compared to large breeds and incidence increases with advancing age. In prevalence studies 84% of beagles over the age of 3 and 100% of poodles over the age of 4 were diagnosed with PD. Current knowledge of the rate of progression of PD is limited. The objective of this study was to determine the rate of PD progression in miniature schnauzers, an at risk small breed of dog. Dogs (n = 52, age 1.3-6.9 years) who had received a regular oral care regime prior to this study were assessed for levels of gingivitis and periodontitis around the whole gingival margin in every tooth under general anaesthetic. Assessments were conducted approximately every six weeks for up to 60 weeks following the cessation of the oral care regime. Results: All of the 2155 teeth assessed entered the study with some level of gingivitis. 23 teeth entered the study with periodontitis, observed across 12 dogs aged between 1.3 and 6.9 years. 35 dogs had at least 12 teeth progress to periodontitis within 60 weeks. Of the teeth that progressed to periodontitis, 54% were incisors. The lingual aspect of the incisors was significantly more likely to be affected ( p < 0.001). The severity of gingivitis in periodontitis-affected teeth was variable with 24% of the aspects affected having very mild gingivitis, 36% mild gingivitis and 40% moderate gingivitis. Periodontitis progression rate was significantly faster in older dogs. Only one dog (age 3.5) did not have any teeth progress to periodontitis after 60 weeks. Conclusions: This is the first study to have assessed the progression rate of periodontitis in miniature schnauzers and highlights that with no oral care regime, the early stages of periodontitis develop rapidly in this breed. An oral care regime and twice yearly veterinary dental health checks should be provided from an early age for this breed and other breeds with similar periodontitis incidence rates. Keywords: Dog, Gingivitis, Periodontitis, Periodontal disease, Miniature schnauzer

Background Periodontal disease (PD) is the most widespread oral disease in dogs and prevalence estimates of 44%, 56%, 60% and 63.6% have been reported [1-4]. The incidence and severity of the disease has been shown to increase with age [2,4,5]. In a study of poodles, 90% under 4 years of age and all dogs older than four years were reported to have at least one tooth with periodontitis [5]. Kortegaard et al. observed that all research beagle dogs in their study, regardless of age, had gingi vitis diagnosed by bleeding on probing [2]. In that study * Correspondence: [email protected] 1 The WALTHAM Centre for Pet Nutrition, Melton Mowbray, Leicestershire LE14 4RT, UK Full list of author information is available at the end of the article

20% of dogs aged between 1 and 2 years had clinical attachment loss, increasing to 61% of dogs aged between 2 and 3 years and 84% of dogs aged 3 years or over [2]. In an earlier study of 162 dogs of various breeds, 37% of dogs aged younger than 2 years were affected with marginal periodontitis, rising to 55.2% of dogs aged 3–5 years and 82.3% of dogs aged six years or older [4]. Periodontitis has also been reported to be more prevalent in small breeds compared to large breeds [3,4,6]. In addition, brachycephalic breeds and dogs with tooth overcrowding have been reported to be especially vulnerable to developing the advanced stages of the disease [7]. The number of affected teeth has also been shown to vary considerably between dogs of the same breed [2,5].

© 2014 Marshall et al.; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited.


Page 2 of 13

Disparities in reported prevalence estimates are likely due to differences in age and breed compositions of the study groups. The criteria used to establish the diagnosis of PD will also affect the reported prevalence estimates. Some studies report gingivitis, plaque and calculus as disease conditions [3,8] whilst others include clinical attachment loss and periodontal probing depth as measures of periodontitis [2,5]. Bone loss during postmortem examination [4] or determined by dental radiology [1] have also been utilized to determine diagnosis. In addition, the thresholds used for diagnosing pathological pockets and clinical attachment loss differ between studies. For example, Kyllar & Witter [3] used probing depths of between 1 and 2.5 mm to determine early periodontitis in various breeds of dog, whereas Hoffmann & Gaengler [5] classified a periodontal pocket of 3-5 mm as slight periodontitis in poodles. The sample sizes studied also vary which will affect the precision of the estimates obtained and some of the studies have only examined a subset of the dentition [3,9]. These variations are not unique to veterinary dentistry. There are also many indices used to assess the clinical status of human patients in periodontology research studies [10,11]. The aforementioned differences make it difficult to compare studies and may risk overstating or understating the problem. The aim of this study was to determine the incidence and progression of gingivitis and periodontitis in miniature schnauzer dogs based on full-mouth examinations using periodontal probing depth, gingival recession and furcation exposure as indicators of clinical attachment loss.

Results Number of assessments

The number of dogs and number of teeth assessed at each measurement are reported in Table 1. Dogs were assessed at 6 week intervals (+/− 1 week) for between 3 and 11 times over the course of the 60 week study. One dog was not assessed at the first 6 week time point due to health reasons unrelated to the study. The number of teeth within a dog that progressed to periodontitis ranged from 0 to 21. Some dogs had less than 12 teeth affected at one assessment period meaning that they stayed on trial for one more 6 week period but by the time of the next assessment up to 21 teeth were affected.

Periodontal health status at start of study

One dog aged 2.5 years joined the trial with 6 teeth affected by periodontitis. Eleven dogs had either 1 or 2 teeth affected by periodontitis and were aged between 1.3 years and 6.9 years (mean 4.5 years). The 23 teeth identified as having periodontitis at the start of the study were not included in subsequent analysis. All of the dogs were observed to have gingivitis at the first assessment. Gingivitis was assessed on 4 individual aspects of each tooth. Of the 8526 measurements recorded 61 (0.7%) of the aspects were classified as healthy having no gingivitis or active periodontitis (gingivitis level 0 or G0) whilst 5653 (66.3%), 2294 (26.9%) and 518 (6.1%) aspects entered the study with gingivitis levels 1, 2 and 3 (G1, G2 and G3) respectively (Figure 1). No tooth was observed to be healthy around the whole gingival margin with 24.8% of the teeth having a maximum gingivitis level of 1, 57.4% having a maximum gingivitis level of 2 and 17.8% of the teeth having a maximum gingivitis level of 3. Incidence of periodontitis

Of the teeth that progressed to periodontitis (28.3% of the total teeth assessed), the incisors were the most represented tooth type and the canines the least represented (Table 2). When assessing individual teeth in the mandibles, the least affected teeth were the canines; the 1st, 2nd and 3rd premolars and the 2nd and 3rd molars which all had low levels of periodontitis (less than 11%). In contrast, all three incisors along with the 4 th premolar and the 1st molar all showed high levels of periodontitis with between 29.4 and 72.5% of those tooth types affected. The same pattern was repeated on the maxillae, though the differences were less pronounced (Figure 2). To assess the position on the tooth where periodontitis occurred, each tooth was assessed around the whole gingival margin and data were recorded for four aspects of each tooth (Table 3). Only eight incidences of gingival recession or furcation exposure were observed throughout the study. Therefore, only the effect of increased probing depth was considered in this analysis. The palatal/lingual aspect of the incisors had a significantly higher proportion of periodontitis compared to other aspects ( p < 0.001). The premolar teeth were significantly more likely to be affected on the distal aspect ( p < 0.001) whilst the molar teeth had a significantly higher proportion of periodontitis on the mesial and palatal/lingual aspects compared to the mid-buccal and distal aspects ( p < 0.001)

Table 1 Number of animals and number of teeth assessed at each time point Time from trial start (weeks +/ − 1 week)

0

6

12

18

24

30

36

42

48

54

60

Total animals assessed

52

51

52

51

49

43

38

30

26

20

15

2155

2092

2096

1996

1871

1616

1384

1079

912

675

505

Total teeth assessed


Page 3 of 13

2000

6 6 7 1

e r o c s s 1500 i t i v i g n i g h c a e 1000 h t i w h t e e t f o r e b 500 m u N

0

Gingivitis 0 Gingivitis 1 3 3 5 1

1 1 5 1

Gingivitis 2 Gingivitis 3

9 2 0 1 3 4 8

3 1 5

6 7 4 6 7 2 1 9

8 1

7 2

Mesial

2 6

6 0 1

6 1

Mid-Buccal

9 5 2

0

Distal

Palatal/Lingual

Aspect

Figure 1 The number of teeth with each gingivitis score at first measurement, expressed by aspect.

(Figure 3). The majority of this difference was driven by the high level of increased probing depths observed at the point where the distal aspect of 4th premolar meets the mesial aspect of the 1st molar in both maxillary and mandibular quadrants.

Rate of periodontitis disease progression

Rates of periodontitis disease progression were modelled for each tooth type (Figure 4). There were a number of teeth that were estimated to have statistically significant differences in their rates of progression. For example, the predicted time it takes the mandibular 4th premolars to progress to periodontitis was significantly lower than any of the other mandibular premolars ( p < 0.001) and the 1st mandibular and maxillary molar teeth were significantly more likely to progress than all of the other molar teeth ( p ≤ 0.007). The maxillary 2nd molars and the right mandibular 2nd and 3rd molars had no observed periodontitis and the model predicted that they would require 102 weeks to reach the disease state.

Relationship between age and the rate of periodontitis progression

There was a significant linear effect of age on the time it takes the teeth to progress to periodontitis. With every year’s increase in age there was a reduction in time to periodontitis of 5.5 (s.e. 1.21) weeks (Figure 5) demonstrating that as dogs age they progress to periodontitis significantly faster than younger dogs.

Relationship between gingivitis and periodontitis

The distribution of gingivitis scores on the aspects of the teeth affected by periodontitis are shown in Figure 6 and Table 4. It is clear that the palatal/lingual and buccal aspects behave quite differently. On the palatal/lingual aspect, periodontitis is often associated with later stage gingivitis (mostly levels 2 and 3) whereas no such relationship exists for the combined buccal aspect where the highest proportion of teeth that progressed to the early stages of periodontitis were observed to have gingivitis level 1.

Table 2 Summary of teeth which progressed to periodontitis (not including periodontitis teeth at T0) Tooth type

Number of teeth at trial start

Sum of PD teeth

% of each tooth type which progressed to PD

% of total PD teeth

Incisor

609

327

53.7

54.1

Canine

208

12

5.8

2.0

Premolar

808

180

22.3

29.8

Molar

507

85

16.8

14.1

Total

2132

604

28.3

100.0


Page 4 of 13

Figure 2 The percentage of each tooth which progressed to periodontitis.

To further explore the relationship between gingivitis and periodontitis the progression rate of gingivitis was assessed. There was a significantly faster rate of gingivitis progression for teeth that progressed to periodontitis compared to those teeth that did not ( p < 0.001) (Figure 7). To determine whether the gingivitis score was a predictor of future time to periodontitis the starting scores for each tooth were examined to see whether they influenced the likelihood of progressing to periodontitis in the trial. Table 5 shows that similar proportions of teeth developed periodontitis regardless of the starting gingi vitis score. This was supported by modelling the time it takes for each tooth to develop periodontitis for each starting gingivitis state. Although this showed that the

time that teeth took to progress to periodontitis starting from a baseline gingivitis score of 1 was significantly different to teeth starting at gingivitis level 3 ( p = 0.011) (Figure 8), the difference in rates was actually very small. Teeth starting with gingivitis level 1 would take on average 66.8 weeks to develop periodontitis whilst teeth starting at gingivitis levels 2 and 3 would take 65.6 and 64.0 weeks, respectively.

Discussion This study describes the incidence and progression of periodontitis in 52 miniature schnauzers based on full mouth examinations over a period of up to 60 weeks. Dogs as young as 1.3 years were affected by the early stages of

Table 3 Percentage of each aspect that developed periodontitis out of all aspects for that tooth type Tooth type

Aspect Mesial

Mid-Buccal

Distal

Combined buccal aspects

Palatal/Lingual

Incisor

4.27

0

7.22

11.49

44.99

Canine

2.4

1.44

1.92

5.76

0.96

Premolar

3.47

1.36

13.12

17.93

8.17

Molar

10.85

1.24

0.99

13.08

8.44


Page 5 of 13

Figure 3 Probability of each aspect progressing to periodontitis. Error bars signify 95% confidence intervals.

Figure 4 Estimated time for each tooth to progress to early stage periodontitis. Green triangles and blue diamonds = right-hand side of the mouth; red squares and black circles = left hand side of the mouth. Error bars signify 95% confidence intervals.


Page 6 of 13

Figure 5 Estimated linear fit of age against time to periodontitis with 95% confidence limits.

periodontitis. Only one dog did not develop periodontitis in any teeth during the course of this study and 35 dogs developed the early stages of periodontitis in 12 or more teeth within 60 weeks of stopping the oral hygiene programme. Numerous studies have demonstrated a

correlation between age, prevalence and severity of periodontal disease [2-6]. This study has also shown that as dogs age they progress towards periodontitis more quickly than younger dogs when efforts at maintaining oral hygiene are stopped.

210

e r o c s 180 s i t i v i g150 n i g h c 120 a e h t i w 90 s t c e p 60 s a f o t n 30 u o C

2 9 1

Gingivitis 1 Gingivitis 2 Gingivitis 3 1 4 1 9 1 1 8 9 4 7 3 4

0

Combined Buccal

Palatal/Lingual Aspect

Figure 6 Histogram of gingivitis scores for each aspect of the tooth affected with periodontitis.


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Table 4 Percentage of aspects with each gingivitis score, for aspects affected with periodontitis Aspect

Gingivitis score 1

2

3

Total

Mesial

7.65

6.15

3.30

17.09

Mid-Buccal

1.35

1.05

0.45

2.85

Distal

8.85

7.50

7.35

23.69

17.84

14.69

11.09

43.63

6.45

21.14

28.79

56.37

Combined Buccal aspects Palatal/Lingual

Previous studies have reported prevalence rates of periodontitis ranging from 44 to 63.6%, in mixed age populations [1-4], rising to 84% in dogs aged 3 years or older [2], 82.3% when dogs reach the age of 6 years or older [4] and in one study, periodontitis was present in 100% of poodles over the age of 4 years [5]. In this study 98% of dogs had developed some level of periodontitis within 30 weeks of stopping toothbrushing. This high record of incidence is likely to be a consequence of 3 factors. Firstly, every single tooth in every dog was analysed around the whole of the gingival margin; secondly the breed studied (miniature schnauzer) is known to be a high risk breed for periodontitis (internal data – unpublished) and thirdly the very earliest stages of periodontitis were measured.

In this study, preventative tooth brushing was stopped either one week or 18 weeks prior to the first measurement. The dogs that had tooth brushing stopped 18 weeks earlier were used in a pilot study to assess the optimal time interval for dental assessments to correctly determine periodontitis progression. All dogs started the trial with some level of gingivitis (0.7% of aspects were healthy). This therefore suggests that gingivitis develops rapidly even in young dogs of this breed (minimum age 1.3) when an oral care regime is removed. This is consistent with a previous longitudinal study in beagle dogs, where all dogs exhibited gingivitis within 2 weeks of tooth brushing being removed (control dogs who received twice-daily tooth brushing showed no gingivitis) [9]. Consistent with other studies, gingivitis did not always lead to periodontitis in this study [12-14]. Rates of progression were estimated for each tooth and tooth type by modelling the time that each takes to progress to periodontitis (Figure 4). Unsurprisingly, the teeth that had the highest incidence levels also had the fastest estimated rates of progression. This model suggests that the incisors, 4th premolars and 1st molars are the teeth that develop periodontitis the fastest. The 110, 210, 410 and 411 molar teeth, for example, did not de velop periodontitis in this study and were modelled as requiring 102 weeks to progress. A further study of a

Figure 7 Gingivitis score progression rate according to periodontitis progression. Mean rate of gingivitis score progression per year in periodontitis affected aspects compared to aspects with no periodontitis progression, with 95% confidence intervals.


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Table 5 Numbers and proportions of teeth progressing to periodontitis compared to starting gingivitis score of teeth Starting gingivitis score

Number at start

Number of teeth which developed periodontitis

Percentage of teeth which developed periodontitis

G1

528

114

21.59

G2

1224

370

30.23

G3

380

120

31.58

design that allows all teeth to progress to periodontitis would be required to validate these model estimates. There was a low incidence of periodontitis in the canines and rostral premolars and it was rarely observed in the 2nd and 3rd molars. These results are consistent with a study of a population of 162 dogs of various breeds in which the molars and distal premolars were more often affected by periodontal lesions compared to the rostral premolars and canines [4]. In contrast, in a population of 123 poodles the highest incidence of periodontitis was in the canine teeth [5]. However, in the poodle study, the highest rate of missing teeth was in the incisors and first premolar teeth P1 which may indicate high levels of periodontitis-related tooth loss. In this work dogs were removed from the study if they developed the early stages of periodontitis in 12 or more teeth and therefore incidence rates are likely to be underestimated since not all teeth had the same opportunity to

progress to periodontitis. The decision to remove dogs from trial that had 12 or more periodontitis affected teeth was made to balance the need to have sufficient numbers of most tooth types progressing to periodontitis without compromising the welfare of the dog. To determine the actual incidence rate for tooth types that progress more slowly, a study design is required in which every tooth type is able to progress to periodontitis. This study design would be likely to result in the teeth that have more rapid progression rates reaching the later stages of periodontitis (PD2 and above). This design does not fit within our ethical or animal welfare policies and so was not pursued. In a previous study by Lindhe et al. [9] the upper premolars and molars exhibited increased loss of attachment compared to the lower premolars and molars in Beagle dogs [9]. In contrast, in this study the lower distal premolar and rostral molar teeth exhibited increased

Figure 8 Average time to periodontitis by starting gingivitis score. Estimated average time to periodontitis for teeth by baseline maximum gingivitis scores with 95% confidence intervals. Letters represent Tukey HSD homogenous groups at the 5% level.


incidences of periodontitis compared to the same teeth on the maxilla. The aspect which was most frequently associated with periodontitis on the 4th premolar teeth in this study was the distal aspect of the buccal surface, whilst the 1st molar teeth were most affected on the mesial aspect. This may be due to a build up of plaque between these two teeth which may in turn lead to pathology. There is some evidence that calculus build up is greater on the maxillary 4 th premolar and 1st molar in multiple breeds of dogs [6] and the position of the parotid and zygomatic salivary duct openings has been suggested as a probable factor for the increased levels on the upper 4th premolar [15]. Calculus wasn’t measured in this study as it isn’t considered the primary aetiological factor in periodontitis [16] so a direct comparison of calculus build up and disease progression cannot be made. The reason for this difference between tooth types is unclear but may be related to the way that dogs in this breed eat their food or maybe due to salivary flow behind the incisors. These potential relationships are yet to be investigated. The majority of the periodontal pockets observed in this study occurred on the palatal/lingual aspect of the teeth (Table 3). This initially appears to contrast with a previous study of 408 dogs of various breeds, size and age, which observed that the buccal surface of the teeth was more affected than the palatal/lingual surface [3]. However a closer inspection of the data reveals that the vast majority of the periodontitis found on the palatal/ lingual aspect occurs on the incisors and that on the other tooth types (canines, molars and premolars) periodontitis was more commonly associated with the buccal aspect (Table 3). Taken together, these differences between the teeth and aspects affected in different studies suggest that there are breed differences that determine which teeth are most likely to develop periodontitis. It has previously been documented that brachycephalic breeds and dogs with tooth overcrowding are more vulnerable to periodontitis [7]. Tooth overcrowding in the incisor region of miniature schnauzers may explain why a high incidence of periodontitis was observed in this study. The close proximity of these teeth to each other may allow transfer of disease-associated plaque bacteria and thus increase the burden of disease. Similarly, the overlap between the distal premolar P4 and the rostral molar M1, may lead to a build of plaque and ultimately disease. In addition to plaque potentially causing disease in this region, the close proximity of these two teeth increases the likelihood that any loss of attachment or bone may affect both teeth. The incidence of periodontitis and estimated progression rates differed for every dog, tooth type and aspect, consistent with previous studies which suggest that

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periodontal lesions do not progress at the same rate [9,17]. For example, one dog aged 3.5 years did not de velop any periodontitis during the study. Another dog aged 6.8 years only developed periodontitis in 2 teeth in the 60 week time frame despite four of his siblings de veloping periodontitis in 12 or more teeth within 42 weeks. There was a significant linear effect of age on the time it takes the teeth to progress to periodontitis in this study. With every year’s increase in age there is a reduction in time to periodontitis of 5.5 (s.e. 1.21) weeks (Figure 5). It has previously been reported that a positive correlation exists between increasing age, and the prevalence and severity of periodontal disease [6,7,11,14]. This study has shown that older dogs progress to periodontitis faster than younger dogs. The reason/s for these differences are not clear. One could hypothesise that the response of the immune system to the bacteria alters with age. Lowered immunity in aged subjects, or immunosenescence, is an accepted phenomenon in humans as is increased proinflammatory status which is believed to be a causal factor in increased mortality rates in the elderly [18]. Changes in immune parameters with age in dogs have been reported in Labrador retrievers ranging in age from 0.8 to 11.5 years and 2 to 10 years [19,20] and fox terriers mean age 1.8 years compared to mean age 11.5 years [21]. Breed differences have also been proposed between German shepherd dogs and Labradors [22]. It has been reported that these changes in the immune response are similar to that seen in humans and contribute to the ageing process in dogs [23]. Therefore, older dogs may have increased severity in periodontitis because they have either been affected for longer or because their immune system can either no longer cope with the pathogenic attack or develops an excessive inflammatory response. A number of studies have challenged the previously held view that gingivitis always progresses to periodontitis [24]. Here we have reported that teeth that progress to early stage periodontitis have a more rapidly progressing gingivitis score compared to teeth that do not progress to periodontitis. This could suggest a relationship between gingivitis and periodontitis. However, in teeth that progress to periodontitis the rate of progression of gingivitis is slow. When the length of this trial is considered (60 weeks) it becomes clear that the speed of gingi vitis progression that was observed was not rapid compared to progression towards periodontitis. Furthermore, only 31.58% of teeth that were scored as G3 at baseline progressed to periodontitis which was similar to teeth that were scored as G1 at baseline (21.59%). In addition, the predicted rate at which teeth would de velop periodontitis was similar regardless of whether the teeth started in gingivitis level 1 or 3. Finally we have


reported that on buccal aspects, when periodontitis was first detected the associated gingivitis score was more likely to be G1 than G3. However in contrast, on palatal aspects there was a greater tendency for periodontitis to be associated with higher gingivitis scores. Taken together the data reported in this study indicate that there is only a weak relationship between gingivitis and progression to periodontitis. Of particular significance is the fact that the current gingivitis state of a tooth does not predict the time that tooth will take to get periodontitis. This is consistent with human studies which reported that most sites of gingivitis did not progress to periodontitis [24]. The lack of a strong relationship between gingivitis and periodontitis may result from the inherent variability seen in the method. The gingivitis score relies heavily on one particular feature, time to bleeding. It is not known if there is any biological significant difference between bleeding that happens slightly delayed or immediately and yet one gives a score of 2 and the other 3. The technique is also subjective in nature which adds to the noise. To effectively assess gingival and periodontal health a more objective method is therefore required that relies on biological markers of disease progression that are more sophisticated than simple time to bleeding or gross inflammation. An improved understanding of the biological changes in the canine immune response and the bacterial population in the oral cavity that occurs during progression towards periodontitis would undoubtedly be a good first step. This longitudinal assessment has reported the estimated rates of progression of periodontitis in different tooth types in adult miniature schnauzers. The effects of age, tooth type and aspect observed in this study were identified over and above the noise in the data due to veterinary treatment and diet. The teeth most likely to progress to periodontitis in this breed are the incisors, 4th premolars and 1st molars. It is clear that not every dog or indeed every tooth within a dog is equally affected. This study has highlighted the value of whole mouth, site specific examinations over time. Over half of the periodontal pockets detected were on the lingual or palatal aspect of the tooth. This supports the evidence that examining a dog with a conscious assessment of gum health on the buccal surface is insufficient to diagnose periodontal disease. Miniature schnauzers in this study developed periodontitis from a young age (as young as 1.3 years) and the likelihood of developing the disease increased with age. The disease typically progressed on aspects of the teeth that cannot be readily seen in a conscious oral examination. Based on the results of this study, in the absence of an effective oral care regime periodontitis will develop rapidly in this breed and if left unchecked could

Page 10 of 13

progress further and ultimately lead to loss of teeth and significant discomfort for the dog [7,16]. Periodontitis has also been associated with a number of serious systemic diseases such as endocarditis and renal disease in humans [25] and renal, hepatic and cardiac disorders in dogs [13]. It is therefore of great benefit to maintain dogs in good periodontal health which for this breed requires a regular oral care regime and ideally frequent dental assessments. Given the rate of development of periodontitis observed in this study, dental assessments need to be at least twice yearly to have the best chance of catching the disease in its earliest stages. It is reasonable to assume that twice yearly dental assessments of other small and toy breeds with similar periodontitis incidence rates are likely to be beneficial.

Methods Dogs

Fifty two miniature schnauzers aged between 1.3 and 6.9 years, with an average bodyweight of 8.8 kg (range 6.6 – 11.4) and housed at the WALTHAM® Centre for Pet Nutrition were enrolled in this study. Twenty eight dogs were female (at the start of the trial entire n = 9, neutered n = 19) and 24 were male (all neutered). Two of the bitches were subsequently spayed some 18 and 42 weeks into the study. All dogs had been on an oral care regime of toothbrushing every second day since approximately 1 year of age. Toothbrushing was stopped between one week (n = 42 dogs) and 18 weeks (n = 10 dogs) before the first dental assessment. The latter group had been on pre-trial study to determine the optimal time window for making dental assessments. The date of the final intervention was used as time zero in the statistical models assessing disease progression rates. All dogs received a pre-study veterinary examination to ensure suitability for trial, which included a physical examination, routine blood work and an assessment of the dog ’s veterinary history. This study was approved by the WALTHAM® Ethical Review Committee and run under licensed authority in accordance with the UK Animals (Scientific Procedures) Act 1986. Dental assessment procedures

Dental assessments were performed under general anaesthesia. Following a pre-medication of acepromazine (0.05 mg/kg) and buprenorphine (0.02 mg/kg), general anaesthesia was induced by an injection of propofol (4 mg/kg) via an intravenous catheter. Gaseous anaesthesia was maintained with oxygen and isoflourane via a cuffed endotracheal tube. Six people were used for the dental scoring assessments. The scorers were all trained by a Recognised European Specialist in Veterinary Dentistry (LM) and


Page 11 of 13

then calibrated 2 weeks prior to the start of the trial to ensure consistency between scorers. During the course of the trial all scorers were re-assessed at least every 3 months to ensure consistency was maintained across time. Each dog was assessed by the same scorer throughout the whole trial (with a minor number of unavoidable exceptions for illness etc.). Scorers were not permitted to review previous results and in effect were assessing the dogs blind. In addition, a second scorer was also present to confirm or reject the depth of a periodontal pocket if required. All teeth were scored individually at each assessment. Each measurement was taken at the gingival margin using a periodontal probe. A gingivitis score between 0 and 4 was recorded for the mesial, mid-buccal, distal and palatal/lingual aspect of each tooth using a modified combination of the gingival index (GI) and sulcus bleeding index (SBI) [26]. Probing depth, gingival recession and furcation exposure were recorded according to the criteria in Table 6. Probing depth was measured from the gingival margin to the bottom of the periodontal pocket. Gingival recession was measured from the cementoenamel junction (CEJ) to the gingival margin using the graduations of a periodontal probe. Total attachment loss was calculated as the sum of the gingival recession and the periodontal probing depth in accordance with established protocols [12,16]. No evidence of gingival hyperplasia was observed. In this study, where the very early stages of periodontitis were identified, total attachment loss was the result of an increase in periodontal probing depth except on 8 occasions; 4 of which were incidences of gingival recession and 4 of which were when furcation exposure was observed. Periodontitis stage 1 (PD1) was classified as being up to 25% attachment loss and periodontitis stage 2 (PD2) as between 25 and 50% attachment loss. Each dog was assessed every six weeks +/− 1 week for up to 60 weeks.

To avoid teeth progressing to the later stages of PD, they were scaled and polished as soon as periodontitis was detected and then no longer included in the study. These periodontitis teeth were scaled and polished at every subsequent assessment until the dog left the trial. The variable rate of periodontitis progression resulted in 12 teeth reaching PD2 at the first time they were detected as having periodontitis. These teeth were scaled and polished in the same way as teeth that had reached PD1 and were also included in the analysis of the results. No teeth progressed past PD2 during the course of the trial. If a dog developed periodontitis in 12 or more teeth it received a full mouth scale and polish, was removed from the study, and the oral care regimen of toothbrushing was reinstated. These oral care criteria were selected to prevent any teeth progressing to later stages of periodontal disease. An earlier study (data not published) had shown that placing dogs at an early stage of periodontitis on to a toothbrushing regime following a full mouth scale and polish would maintain their oral health status and prevent further disease progression. Dogs were routinely maintained on a dry kibble diet. Some of the dogs were on nutritional research studies and on occasion they were fed diets that were either a mixture of dry and wet, dry soaked in water or a solus wet diet (Figure 9). Across all of the dogs 83% of the feeding events were of a solus dry diet with a range of 46% to 100% in individuals. Routine veterinary care was permitted throughout the study as required, which on occasions included administration of antibiotics and anti-inflammatory drugs. Records of these and other veterinary treatments were maintained for each dog. Statistical methods

The probability of progressing to periodontitis was analysed by generalised linear mixed models, for binary data,

Table 6 Miniature schnauzer periodontal disease scoring system (adapted from Wiggs & Lobprise, [26]) Score

Gingivitis

Periodontal probing depth (mm)

Gingival recession (mm)

Furcation exposure

Health (G0)

No gingivitis, pink (or pigmented) healthy gingiva, no inflammation and no bleeding on probing

<1

0

0

G1

Very mild gingivitis (red, swollen but no bleeding on probing)

≥1

0

0

G2

Mild gingivitis (red, swollen and delayed bleeding on probing)

≥1

0

0

G3

Moderate gingivitis (red, swollen and immediate bleeding on probing)

≥1

0

0

G4

Severe gingivitis (ulceration, spontaneous haemorrhage, profuse bleeding on probing)

≥1

0

0

PD1

G1-G4: gingivitis must be present (i.e. active periodontitis)

>2 (>3 on canine teeth)

>0

Grade 1; feel an indentation between the roots and the probe may advance 1 mm.

PD2

G1-G4: gingivitis must be present (i.e. active periodontitis)



Grade 2; obvious indentation between the roots and probe advances 50%.


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l a m i n A

Day of trial Figure 9 Bar chart showing the diet types fed to each animal for the duration of the trial.

with tooth nested in dog as the random effects and aspect, tooth type and their interaction as the fixed effects. A significance level of 5%, after Bonferroni correction, was used to compare mean probabilities (within tooth type, between aspects and within aspects between tooth types). Due to the censored nature of the data the estimated probabilities are likely to be underestimates of the real life progression rates. Prior to this analysis the teeth that had periodontitis at baseline measurement were removed. The time to progress to periodontitis was estimated by censored ANOVA analyses [27]. This analysis allows incorporation of the teeth that were taken off study before they were allowed to progress (i.e. censored observations). The censored observations also included those teeth which did not progress to periodontitis because the dog was removed from trial before the entire dog’s dentition developed periodontitis. The final model incorporated tooth nested in dog as the random effects, tooth and baseline gingivitis score as categorical fixed effects and age as covariate. Comparisons between estimated mean times to progress to periodontitis were made using Tukey HSD tests at the 5% level. The model building also investigated the fixed effects of gender, diet format, percentage of measurements on a veterinary treatment and plausible twoway interactions, however these were dropped from the model due to lack of significance, with p > 0.05. The rate of change of gingivitis was estimated for each aspect (that had at least 4 time points) of each tooth by linear regression with time. The resulting rates of change

were analysed by linear mixed models, incorporating aspect nested in tooth nested in dog as random effects and tooth number, periodontitis status at the end of the study, aspect as fixed effects, along with tooth type, jaw and their interaction. The model building also investigated fixed effects of age, gender, diet format, percentage of measurements on a veterinary treatment and plausible two-way interactions, however these were dropped from the model due to lack of significance, with p > 0.05. Analyses were performed using GenStat v14 statistical software [28]. Abbreviations CEJ: Cementoenamel junction; G0: Gingivitis level 0 (healthy gingiva); G1: Gingivitis level 1 (very mild gingivitis); G2: Gingivitis level 2 (mild gingivitis); G3: Gingivitis level 3 (moderate gingivitis); G4: Gingivitis level 4 (severe gingivitis); GI: Gingival index; PD: Periodontal disease; PD1: Periodontitis stage 1 (up to 25% attachment loss); PD2: Periodontitis stage 2 (25-50% attachment loss); SBI: Sulcus bleeding index. Competing interests Mark Marshall, Corrin Wallis, Alison Colyer and Stephen Harris work for Mars Petcare. Authors contributions MDM – participated in the design and co-ordination of the study, maintained data integrity, drafted and prepared t he manuscript; CVW – participated in the design and co-ordination of the study, drafted and reviewed the manuscript; LM – participated in the design of the study, assisted with clinical scoring methodologies, assisted with results interpretation and reviewed the manuscript; AC – participated in the design of the study, performed all statistical analyses and reviewed the manuscript; ADT – built the database for capturing all data, participated in study modification, maintained data integrity and delivered the final dataset; SH – conceived and participated in the design and ’


co-ordination of the study, reviewed the results and reviewed the manuscript. All authors have approved the final article. Acknowledgements From WALTHAM® the authors would like to acknowledge the significant contribution of Colleen Irvine, Amelia Wagstaff, Sandy Bailey, Wendy Bailey, Karen Billington and Judith Allsopp for providing technical expertise and performing all of the clinical assessments; Andrea Burnham, Russell Newnham, Jonathan Tesh, and Ruth Bates for providing support with animal procedures; Richard Cowan, Zoe Marshall-Jones and Robert Wiggall for the initial thoughts on study design set-up, project conception and initiation. Author details 1 The WALTHAM Centre for Pet Nutrition, Melton Mowbray, Leicestershire LE14 4RT, UK. 2 The Veterinary Dental Surgery, 53 Parvis Road, Byfleet, Surrey KT14 7AA, UK. Received: 1 August 2013 Accepted: 25 June 2014 Published: 1 September 2014

References

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C ANINE & FELINE A NESTHESIA

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A general anesthetic to a healthy dog should bear little risk to the animal’s life. However, although the mortality rate is very low, morbidity due to anesthesia, which is often overlooked, is not uncommon In man severe hypoxic brain damage can decrease intelligence following general anesthesia which is apparent to families and friends, and similar happenings may occur in dogs Owners may comment that their dog is never the same since the anesthesia which may indicate a cerebral anoxic damage A more dramatic and obvious cause of postanesthetic morbidity in dogs is renal failure Many elderly dogs suffer from some degree of interstitial nephritis and in such animals even mild renal hypoxia may prove fatal within a relatively short time Many choices are available to tailor anesthetic protocols to meet the demand of increased sophistication of diagnostic and surgical procedures, and with smooth induction, careful monitoring in oxygenation, circulation and ventilation, and attention to fluid balance and smooth recovery, a safe anesthesia in dogs can be ensured

Starvation for about 12 hours usually ensures a dog will have an empty stomach Water need not be deprived until premedication is given or until about 2 hours prior to anesthesia Laboratory evaluation can provide useful prescreening information about the general health status of the patient prior to anesthesia, and minimum database are PCV, TP, BUN and glucose A thorough physical examination to determine any abnormalities must be carried out. Auscultation for cardiac dysrhythmias and murmurs, or abnormal lung sounds will provide useful information regarding preexisting cardiopulmonary disease. Stabilize animal’s physiology in debilitated animals (e.g. fluid deficit, acid-base abnormality) IV catheterization placement o The common site of venous catheterization site is cephalic vein o Other veins for venous catheter placement include the recurrent tarsal, saphenous, auricular and jugular veins o For jugular catheterization 16 – 18 G and 2-6 inch long catheter is suitable for most dogs

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A good preanesthetic sedation facilitates smooth induction and has anesthetic sparing effect during maintenance There are many choices available. Sedative/opioid combination (neuroleptanalgesia) is most popular (e.g. acepromazine and morphine), and provides better restraint and analgesia (the combination is synergistic, not merely additive) as preanesthetic medication

Provides mild sedation at clinically prescribed dose (0.01 – 0.05 mg/kg IV, IM, SQ) Anti-arrhythmic Requires at least 20 min for good effect even after IV injection, and 30 to 45 min when given IM, and longer for SQ Prolonged duration Premedication dose of 0.04 mg/kg IM has minimal cardiovascular effect in healthy dogs Will cause hypotension (more so in old, debilitated, or hypovolemic animals) through direct myocardial depression and peripheral vasodilation, and should not be used in these debilitated animals. Decrease seizure threshold, so better to avoid in patients at increased seizure risks Some strains of the Boxer breed are very sensitive to phenothiazine and acepromanxine as little as 0.02 mg/kg IM can cause collapse with the animal becoming very bradycardic and hypotensive. As the symptom is very similar to vasovagal stimulation, it is recommended low dose of acepromazine be given, and atropine or glycopyrrolate be given with acepromazine in this breed. Inexpensive, and very widely used for sedation and premedication

Minor tranquillizer Excellent muscle relaxation Minimal cardiopulmonary depression May cause paradoxical excitement through disinhibition, so best to be given with other CNS depressants (e.g. ketamine, opioids) 0.05 – 0.4 mg/kg IV, IM, SQ Diazepam is more irritant to the tissue so better to avo id giving it IM

Has potent sedative effect, but cardiovascular depression can be profound Causes vomiting Other side effects as seen in other species also occur o Hyperglycemia o Diuresis o GIT motility depression o Platelet aggregation Largely displaced by medetomidine in small animals

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Causes less vomiting than xylazine 5-40 mcg/kg IM, SQ have been given to produce sedation. IV administration is associated with more severe form of dysrhythmias, so generally is not recommended Sedation lasts approximately for one hour The pharmacologic effects of medetomidine in dogs are very similar to those of xylazine in that it causes bradycardia, hyperglycemia, and increased urine production. An exception is that it causes arterial hypertension which is dose-dependent

The most recent alpha 2 agonists Reduces the amount required for the anesthetic induction in dose dependent manner Produces dose dependent cardiovascular depression 10-80 mcg/kg IM, SQ

Widely used to provide analgesia in dogs Provide better sedation and analgesia when combined with other sedatives Morphine is inexpensive and is used in the dose of 0.25-1 mg/kg IM, SQ. IV morphine induces histamine release particularly if given as a rapid bolus, but slow administration is less likely to cause problems Oxymorphone causes less vomiting than morphine and hydromorphone, so is better choice for patients with head trauma, eye injury and gastrointestinal disorders. Combination of benzodiazepines with butorphanol (or buprenorphine) is a useful alternative to the combination with pure opioids for brachycephalics reducing the risk of respiratory depression Opioids induce minimal changes in HR, BP, CO See pain lecture for other available opioids

Anticholinergics are not routinely administered as part of preanesthetic medication Use of atropine or glycopyrrolate may be indicated for animals with high resting vagal tone (e.g. brachycephalics) and procedures likely to increase vagal stimulation (e.g. ocular surgery) Recommended dosages are; atropine 0.02-0.04 mg/kg IV, IM, SQ; and glycopyrrolate 2-10 mcg/kg IV, IM, SQ

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The dose of ketamine which produces anesthesia in dogs is very near to that which causes seizures Ketamine is associated with increased muscle rigidity and excessive salivation Ketamine may cause increased heart rate, cardiac output, and blood pressure A wide range of sedatives are combined with ketamine to induce deep sedation or light anesthesia Medetomidine at 5 – 40 mcg/kg added to ketamine at 2-5 mg/kg given either IM or IV produces deep sedation often recumbency. Butorphanol 0.1-0.4 mg/kg IV, IM can be included in this combination for better sedation, analgesia and muscle relaxation. Although the combination can be given SQ the onset of anesthetic effect is less predictable Medetomidine can be substituted by xyalzine 0.1-0.5 mg/kg, resulting in shorter duration of effect o Ketamine-Diazepam/Midazolam This combination will produce less cardiovascular depression than x ylazine-ketamine Diazepam 0.1-0.4 mg/kg and ketamine 5 mg/kg given IV as a bolus or titrated to effect, or IM injection produce recumbency and status similar to general anesthesia in 2-10 minutes Midazolam is administered at 0.1 – 0.3 mg/kg IV, IM, substituting diazepam Butorphanol 0.1-0.4 mg/kg IV, IM can be included in this combination for better sedation, analgesia and muscle relaxation. ▼

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Telazol up to 4 mg/kg IV to effect or IM produces deep sedation or light anesthesia Side effects associated with ketamine-diazepam use can also be seen (emergence delirium, hypersalivation) Typically used to provide deep sedation in intractable dogs Other sedatives and opioids can be mixed to make the final constituent more potent so as to increase sedation, analgesia and duration of effect, and reduce side effects (e.g. emergence delirium)

The solution of thiopental have a very high pH and the drug can only be given intravenously Induction in unpremedicated dogs can be achieved at the dose of 15 mg/kg IV given the half dose as a rapid bolus and the remaining given titrated to effect In lightly premedicated dogs 7 mg/kg is sufficient to induce anesthetic induction Recovery is through redistribution of the agent from the brain into the other tissues Multiple administration will require the drug to be metabolized, and the dog will have a prolonged recovery with hang-overs lasting for 24 hours or more. Maximum total dose for a fit dog is 30 mg/kg

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It provides rapid induction and is very rapidly eliminated from the plasma. 6 mg/kg IV is calculated dose for the anesthetic induction. Respiratory arrest is not uncommon particularly with rapid IV bolus. It is best given as titrated to effect to produce anesthetic depth just enough to allow endotracheal intubation by slow administration It is non-accumulative and maintenance of anesthesia for prolonged duration can be achieved using a constant rate of infusion.

General anesthesia can be induced by administering isoflurane, halothane, sevoflurane, or desflurane via a facemask There are two methods; ‘incremental’ or ‘crash’ induction ‘Incremental’ induction technique uses 3 min of preoxygenation and then introduction of 0.5 % vapor setting for 30-60 seconds and then 0.5 % increment for the same period. ‘Crash’ induction is achieved with 3-5 % vapor set of isoflurane following pre-oxygenation. The dog will more likely struggle with the crash induction method It is preferable to use non-rebreathing circuits for quicker induction and then switched to the circle rebreathing systems even for animals weighing more than 6 kg Some sample doses of injectable anesthetics in the dog

Comb. # 1 2 3 4 5 6 7 8 9 10

Acepromazine ± Morphine Acepromazine ± Butorphanol Midazolam ± Morphine Midazolam ± Butorphanol Midazolam ± Butorphanol Medetomidine

Dose mg/kg 0.02-0.05 0.25 – 1.0 0.02-0.05 0.1 – 0.4 0.1-0.3 0.25 – 1.0 0.1-0.3 0.1-0.4 0.1-0.3 0.1-0.4 0.002-0.04

Medetomidine ± Butorphanol Xylazine ± Butorphanol Medetomidine ± Butorphanol Midazolam ±Hydromorphone

0.002-0.04 0.1-0.4 0.3-0.5 0.1-0.4 0.002-0.04 0.1-0.4 0.1-0.3 0.05-0.2

Premedication

Thiopental Propofol Thiopental Propofol Thiopental Propofol Thiopental Propofol Ketamine

Dose mg/kg 15 “to effect” 6 “to effect” 15 “to effect” 6 “to effect” 15 “to effect” 6 “to effect” 15 “to effect” 6 “to effect” 5 “to effect”

Diazepam + Ketamine Ketamine

0.25 + 5 “to effect” 5 “to effect”

Diazepam + Ketamine Thiopental Propofol Thiopental Propofol

0.25 + 5 “to effect” 10 “to effect” 4 “to effect” 15 “to effect” 6 “to effect”

Induction agents

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Tracheal intubation in dogs is relatively easily achieved. Dogs can have the mouth wide open and the laryngeal structures are easily viewed Use of laryngeal scope may facilitate the intubation The laryngeal spasm is uncommon, but the animal still needs to be adequately anesthetized to avoid head shaking or excessive coughing reflex Following intubation, correct placement can be confirmed by mild cough, feeling air coming out of the ET tube in synchrony of movement of the chest. If available, reading of CO2 by a capnogrpahy is a useful method to confirm the correct position of the tube Endotracheal tube sizes are proporational to the body weight, typically using 8-12 mm for average 12 - 24 kg dogs. Brachycephalics tend to have hypoplastic trachea and an English bull dog weigh as much as 25 kg could only accept ET tube of 6 mm The cuff needs to be well sealed to prevent aspiration of regurgitants and also to maintain stable anesthetic depth, and to prevent anesthetic exposure to the operators

Inhalation anesthesia is the method of choice for maintaining anesthesia for most prolonged procedures. Intravenous anesthetic techniques based on propofol have become more commonly employed, particularly in animals with concerns for neuroprotection, or for those procedures with limited availability of inhalational anesthesia (e.g. MRI)

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Halothane, isoflurane, sevoflurane, desflurane and nitrous oxide are available The advantages are patent airway, rapid control of anesthetic depth, quick and smooth recovery, and disadvantages are more pronounced cardiovascular depression including myocardial depression, hypotension, and bardycardia

Analgesia from N2O reduces inhalational anesthetic requirement therefore less cardiovascular depression. However, the potency of nitrous oxide is only half that of human, so the sparing effect is not as obvious Use of this agent is not widespread in dogs

1 MAC halothane in dog is 0.8 % Vapor setting is at 3-4 % at induction with oxygen flow at 60 ml/kg/min and is reduced between 1-3 % during the maintenance with oxygen flow at 20 ml/kg/min This is no longer market in the US, and has been largely displaced by isoflurane As anesthesia is deepened by increasing halothane concentration, CO and arterial pressure decrease further. HR usually remains constant.

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Used to be much more expensive than halothane, but now much more affordable and has replaced halothane both in human and veterinary markets worldwide Quicker anesthetic stabilization and more rapid recovery than halothane due to its lower blood gas solubility 1 MAC in dogs is 1.3% Vapor setting is at 3-4 % in dogs at induction with oxygen flow at 60 ml/kg/min and is reduced between 1.5-3 % during the maintenance with oxygen flow at 20 ml/kg/min Isoflurane, similar to halothane, induces a dose-dependent cardiovascular depression. Isoflurane causes more peripheral vasodilation than halothane, which is responsible for a low arterial blood pressure, but tissue looks more bright and pinky indicating better perfusion. Isoflurane is less prone to cause arrhythmia compared to halothane

Anesthetic induction, recovery, and intraoperative modulation of anesthetic depths to be notably faster than halothane and isoflurane. More expensive than halothane and isoflurane, but it is getting less expensive. Sevoflurane (1 MAC = 2.3 %) is less potent than halothane or isoflurane, but more potent than desflurane Sevoflurane induces dose-dependent cardiovascular depression to a degree similar to that of isoflurane

Lower blood/gas partition coefficient than the inhalants mentioned above, so control of anesthetic depth is the quick among the volatile agents in clinical use The least potent among the volatile anesthetics (MAC = 8~11 %) Cardiovascular effects of desflurane are similar with those of isoflurane Expensive as sevoflurane, and requires electronically controlled vaporizer which adds to the inconvenience

Most commonly employed TIVA is based on propofol combination (±opioids; benzodiazepines). The loading dose is in the order of 1-3 mg/kg as a bolus, and this is followed by 2-6 mg/kg/hr The recovery is very complete even following prolonged use. It can be used to induce anesthesia with a single bolus dose, and then to maintain anesthesia using constant rate infusion These combinations are associated with minimal cardiopulmonary depression. However, there are two main limitations to continued administration of intravenous anesthetics; the arterial oxygenation and prolonged recovery. Arterial oxygenation is always at risk with TIVA, particularly with combination of Propofol and opioids, and it is recommended the animal still be intubated and put on 100 % oxygen. Tight anesthetic depth control is more difficult with TIVA so abrupt a wakening during anesthesia is more likely if one is not familiar with the technique and animal’s physiologic reflexes unique to that (inhalant anesthetic provides ad vantage in this respect since monitoring anesthetic concentration in breathing gases allows better anesthetic depth control)

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Anesthetic monitoring is important to maintain a proper plane of anesthesia and to prevent excessive insult to the cardiovascular, respiratory, and central nervous systems. Anesthetic depth can be measured by observation of the following signs: physical move ment or jaw chewing in response to stimulation, eye position and degree of muscle tone, and presence or absence of palpebral reflexes etc. Variables used to monitor the cardiovascular system include h eart rate, pulse pressure, mucous membrane color, and capillary refill time. Direct blood pressure measurement can provide continuous hemodynamic status of the animal and can be easily accomplished through catheterizing the auricular artery. The ECG is useful to monitor cardiac dysrhythmias. The respiratory system is evaluated by monitoring respiratory rate and volume. It can be estimated by observing the emptying of the rebreathing bag of the anesthetic machine during respiratory cycles. Pulse oximetry and/or arterial blood gas analysis provide information of the ventilatory efficiency Ocular reflexes are used to monitor the central nervous system. The palpebral reflex is lost at light planes of anesthesia in ruminants, so it is of little value during anesthesia of these species. Ophthalmic ointment should be applied to the eyes during anesthesia to prevent corneal injury. Body temperature is also an important parameter to monitor during anesthesia. Because of the tendency for anesthetized animals to lose body heat, supplemental heat sources a re often required to maintain adequate body temperature (100-103.5 F). ˚

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Opioids are mainstay analgesic used within perioperative period in the dogs. CNS excitement is rare unlike in cats or horses, but other side effects such as respiratory depression, vomiting and dysphoria are all possible Behavioral changes associated with pain include decreased appetite, aggression, indifference to the surrounding, and avoiding human contacts (see Pain notes) Several types of drugs have been used to provide analgesia including opioids, α2-adrenergic agonists, local anesthetics, and nonsteroidal anti-inflammatory drugs (NSAID’s) of which NSAIDs are most popular (toxicity associated with this agent is much less than in cats) (see Pain lecture). Multimodal analgesic therapy (e.g. morphine, ketamine, lidocaine cocktail CRI) has become more common in use to manage pain Significant variations exist in regards to duration of action and quality of analgesia provided by these agents.

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Body temperature must be maintained so as not to prolong the recovery, and lessen oxygen requirement by muscle tissues. Forced warm air blanket, circulating warm water blanket are very effective to keep the body temperature, but other means such as hot rice socks, used warm fluid bags, hair dryer and infra red lamps are useful external heat sources Endotracheal tube must remain in place until the dog regains at least a couple of strong swallowing reflex to protect the airway, and with return of strong muscle tones. In most brachycephalics the ET tube is well tolerated and the tube can be left until they are evaluated to protect their airway on their own If animals pre-treated with reversible agents, recovery can be expedited by reversing the drugs with specific antagonists. Atipamezole and naloxone are two primary examples and they are best used titrated to effect. If no signs of getting light for longer than 20 minutes, reversal can be considered. Close observation should continue to avoid the animal relapsing into sedation which may expose the animal to potential danger of aspiration or airway obstruction

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Cats are not small dogs and their unique behavioral and physioanatomical differences make anesthesia more challenging than in dogs. Even very friendly cats often object to physical restraint and IV sedative/anesthetic administration in unpremedicated cats can be ex tremely difficult. It would, therefore, be necessary to administer good premedicants to facilitate anesthetic induction in cats. Behavioral alteration following general anesthesia notably due to cerebral anoxic damage as reported in men and dogs is also a possibility and owners may comment that their cat is never the same since the anesthesia Provided that the potential risk is recognized, suitable premedication, a smooth anesthetic induction, careful monitoring, appropriate attention to the oxygenation, ventilation and circulation will ensure a very low morbidity rate in cats.

Starvation for about 12 hours usually ensures a cat will have an empty stomach and water need not be deprived of until or about 2 hours prior to anesthesia Laboratory evaluation can provide useful prescreening information about the general health status of the patient prior to anesthesia, and minimum database are PCV, TP, BUN and glucose A thorough physical examination to determine any abnormalities must be carried out. Auscultation for cardiac dysrhythmias and murmurs, or abnormal lung sounds will provide useful information regarding preexisting cardiopulmonary disease. Stabilize animal’s physiology in debilitated animals (e.g. fluid deficit, acid-base abnormality) IV catheterization placement is not as easy as in dogs so heavier premedication may be required for cooperation o The common site of venous catheterization is cephalic vein o Other veins for venous catheter placement include the saphenous and jugular veins o For jugular catheterization 16-18 G and 2-6 inch long catheter is suitable for most dogs

A good preanesthetic sedation facilitates smooth induction and has anesthetic sparing effect during maintenance There are many choices available. Sedative/opioid (e.g. midazolam and hydromorphone), or dissociative/sedative (e.g. ketamine and midazolam) combinations are most pop ular, and they provide better restraint and analgesia than that achieved by single drug administration with less side effects (e.g. ketamine induced muscle rigidity or opioid induced mania)

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Provides mild sedation at clinically prescribed dose (0.02 – 0.1 mg/kg IV, IM, SQ) Anti-arrhythmic Requires at least 20 min for good effect even after IV injection, and 30 to 45 min when given IM, and longer for SQ Prolonged duration A young, fit cat can tolerate the premedication dose of 0.05 mg/kg with minimal cardiovascular effect A hypertrophic myocardiopathy cat may through decreased afterload via peripheral vasodilation, decreased myocardial oxygen consumption and increased arrhythmogenic threshold. However, in debilitated animals in severe cardiac failure and with decreased circulatory volume its use is contraindicated

When given alone, they produce no obvious sedation in cats They are primarily used as premedicants to counteract ketamine induced muscle rigidity and convulsions Because of its minimal cardiopulmonary depression, it can be a suitable premedicant for cats with underlying cardiopulmonary diseases 0.1 – 0.5 mg/kg IV, IM, SQ for diazepam and 0.1 to 0.3 mg/kg IV, IM, SQ for midazolam Diazepam is more irritant to the tissue so is recommended not to be administered IM

Doses of 0.5 - 1 mg/kg IM are used to produce mild to fairly profound sedation Vomiting and retching are more common at lower end of the doses Cardiovascular depression can be profound Typically used as a premedicant prior to ketamine anesthesia Other side effects as seen in other species also occur o Hyperglycemia o Diuresis o GIT motility depression o Platelet aggregation Largely displaced by medetomidine in small animals

Causes less vomiting than xylazine 5-40 mcg/kg IM, SQ for cats have been given to produce mild to profound sedation. A sublingual spray at 15-30 mcg/kg can be useful to sedate an unmanageable cat. IV administration is associated with more severe form of dysrhythmias, so generally is not recommended Sedation lasts approximately for one hour, but can be antagonized by equal volume of atipamezole if indicated The pharmacologic effects of medetomidine in cats are very similar to those of xylazine It is important to note that increasing the dose of alpha 2 agonists does not increase the depth of sedation, but rather prolongs the duration of sedation

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The most recent alpha 2 agonists Reduces the amount required for the anesthetic induction in dose dependent manner Produces dose dependent cardiovascular depression 10-100 mcg/kg IM, SQ

When given alone, it may induce excitement so is best given with sedatives. When combined with other sedatives it provides better analgesia and sedation Morphine is inexpensive and is used in the dose of 0.1-0.2 mg/kg IM, SQ. This dose is much less than in dogs, but morphine is less well metabolized in cats than in dogs due to deficient glucuronyl metabolic pathways, so it is more likely to overdose and increase the opioid induced excitement Combination of benzodiazepines with buprenorphine (or butorphanol) is a useful alternative to the combination with pure opioids for cats reducing the risk of respiratory depression Opioids induce minimal changes in HR, BP, CO See pain lecture for other available opioids

Anticholinergics are used to reduce excessive salivation (particularly with use of ketamine) 0.02 to 0.04 mg/kg IV, IM, SQ is the recommended dose for atropine Atropine causes visual disturbance so cats need to be handled carefully Glycopyrrolate does not cross the BBB so is preferred for cesarean section, and head trauma patients and is less likely to develop tachycardia than atropine 0.005 to 0.01 mg/kg IV, IM, SQ is the recommended dose for glycopyrrolate

Ketamine administered at 10 to 20 mg/kg IM produces recumbency in the cat within 3-5 minutes. Muscle rigidity and excessive salivation is not uncommon. A wide range of sedatives are combined with ketamine to reduce these side effects and also to reduce the amount of ketamine through a synergism Ketamine may cause increased heart rate, cardiac output, and blood pressure o Ketamine-acepromazine Acepromazine 0.02-0.1 mg/kg IM added to ketamine 10 to 20 mg/kg IM, reduces the muscle rigidity and produces status similar to general anesthesia o Ketamine-medetomidine Medetomidine at 10 - 50 mcg/kg added to ketamine at 5 mg/kg, produces deep sedation often recumbency. Butorphanol 0.1-0.4 mg/kg IM can be included in this combination for better analgesia, sedation and muscle relaxation. Medetomidine can be substituted by xylazine 0.5 – 1.0 mg/kg, with shorter duration of sedation as xylazine has a shorter half life o Ketamine-Diazepam/Midazolam This combination will produce less cardiovascular depression than medetomidineketamine Diazepam 0.25 mg/kg and ketamine 5 mg/kg given as IV bolus induces anesthesia in 1-2 minutes Butorphanol 0.1-0.4 mg/kg IV can be included in this combination for better analgesia and muscle relaxation. ▼

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Telazol up to 4 mg/kg IV to effect or IM produces deep sedation or light anesthesia Side effects seen with ketamine-diazepam can be seen (emergence delirium) Typically used to provide deep sedation in intractable cats Other sedatives and opioids can be mixed to make the constituent more potent so as to increase sedation, analgesia and duration of effect, and reduce side effects (e.g. emergence delirium)

This IV injectable, barbiturate anesthetic is prepared in 1.25 % for use in cats Induction in unpremedicated cats can be achieved at the dose of 15 mg/kg IV given the half dose as a rapid bolus and the remaining given titrated to effect In lightly premedicated cats 7 mg/kg is sufficient to induce anesthetic induction Recovery is through redistribution of the agent from the brain into the other tissues

Advantages and disadvantages of propofol for dogs as described above similarly apply to cats, but there are some unique differences Cats are deficient of glucuronyl transferase, so the phenolic compound is less likely to get metabolized than in dogs, and it has been shown that repeated dosing is associated with some side effects ranging from Heinz body formation, delayed recovery, anorexia, diarrhea, and malaise However, a single IV anesthetic induction dose will bear minimal risks 6 mg/kg IV is administered slowly titrated to effect to induce anesthesia, and in most premedicated cats one third to half of the calculated dose is sufficient to allow ET intubation

General anesthesia can be induced by administering this steroid anesthetic Induction is usually smooth and rapid, but occasionally retching, vomiting and laryngeal spasm can be observed 9 mg/kg IV produces about 15 minute anesthesia with minimal respiratory depression and cardiovascular stability is good Saffan given at 18 mg/kg IM induces anesthesia in 10 minutes which effect lasts 10 to 20 minutes Although contraindicated for use in dogs, Saffan is a safe induction and maintenance agent in cats

General anesthesia can be induced by administering isoflurane, halothane, sevoflurane, or desflurane via a facemask, but a fit, unsedated cat may strongly resent the attempts to force it to breathe volatile anesthetic via a face mask For this reason, many anesthetists prefer to induce inhalation anesthesia by placing the cat in a rectangular glass or clear plastic chamber which the cat accepts with much less struggle In heavily premedicated or debilitated cats, face mask induction can be carried out without excitement or struggling, and is the preferred method of choice The ‘incremental’ or ‘crash’ induction technique used for dogs can be adopted for cats (see above)

Some sample doses of injectable anesthetics in the cat

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Acepromazine ± Morphine Acepromazine ± Butorphanol Midazolam ± Ketamine Diazepam ± Ketamine Midazolam ± Hydromorphone Midazolam ± Butorphanol Medetomidine

Dose mg/kg 0.04-0.1 0.1 – 0.2 0.04-0.1 0.1 – 0.4 0.1-0.3 5 0.1-0.4 5 0.1-0.3 0.05 – 0.1 0.1-0.3 0.1-0.4 0.005-0.04

Midazolam ± Buprenorphine Xylazine ± Butorphanol Medetomidine ± Butorphanol Midazolam ±Hydromorphone

0.1-0.3 0.005-0.01 0.5-1 0.1-0.4 0.005-0.04 0.1-0.4 0.1-0.3 0.05-0.2

Premedication

Thiopental Propofol Thiopental Propofol Thiopental Propofol Thiopental Propofol Thiopental Propofol Thiopental Propofol Diazepam + Ketamine Ketamine

Dose mg/kg 15 “to effect” 6 “to effect” 15 “to effect” 6 “to effect” 15 “to effect” 6 “to effect” 15 “to effect” 6 “to effect” 15 “to effect” 6 “to effect” 15 “to effect” 6 “to effect” 0.25 + 5 “to effect” 5 “to effect”

Diazepam + Ketamine Thiopental Propofol Thiopental Propofol

0.25 + 5 “to effect” 10 “to effect” 4 “to effect” 15 “to effect” 6 “to effect”

Induction agents

The laryngeal spasm is easily provoked, so use of lidocaine spray or short acting muscle relaxant will facilitate the intubation In deep anesthesia laryngeal spasm does not occur, but this is not recommended as a routine procedure. However, where emergency intubation is required following accidental overdose of anesthetic, it is never necessary to use lidocaine spray or muscle relaxant Attempts to carry out forceful intubation through tightly apposed vocal folds, even if initially successful, will result in damage to the mucous membrane with edema and the danger of post-extubation airway obstruction The cat’s larynx may also go into spasm after extubation, so endotracheal tubes should, if there are no surgical contraindications, be removed without any previous deliberate lightening of anesthesia and after careful aspiration of mucous from the airway A standard laryngoscope with an infant size blade is useful to view the laryngeal structure A 4.5 - 5.5 mm ET tube is suitable for most adult cats, and use of stylet can facilitate the intubation

Inhalation anesthesia is the method of choice for maintaining anesthesia for most prolonged procedures. Intravenous anesthetic techniques based on Propofol has become more commonly employed, particularly in animals with concerns for neuroprotection, or for those procedures with limited availability of inhalational anesthesia (e.g. MRI)

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Halothane, isoflurane, sevoflurane, desflurane and nitrous oxide a re available just as in other species. The advantages and disadvantages as described in dogs similarly apply in the cats (see above)

TIVA combination used in dogs as described above based on propofol should still work well in cats with similar dosing. However, as described above prolonged CRI propofol has increased likelihood of toxicity in cats, and thus care must be exercised not to overdose Other advantages and disadvantages of this technique as applicable to the dogs are similar in the cats

Anesthetic monitoring is important to maintain a proper plane of anesthesia and to prevent excessive insult to the cardiovascular, respiratory, and central nervous systems. Anesthetic depth can be measured by observation of the following signs: physical move ment or jaw chewing in response to stimulation, eye position and degree of muscle tone, and presence or absence of palpebral reflexes etc. Variables used to monitor the cardiovascular system include h eart rate, pulse pressure, mucous membrane color, and capillary refill time. Direct blood pressure measurement can provide continuous hemodynamic status of the animal and can be easily accomplished through catheterizing the dorsopedal artery. The ECG is useful to monitor cardiac dysrhythmias. The respiratory system is evaluated by monitoring respiratory rate and volume. It can be estimated by observing the emptying of the rebreathing bag of the anesthetic machine during respiratory cycles. Pulse oximetry and/or arterial blood gas analysis provide information of the ventilatory efficiency Ocular reflexes are used to monitor the central nervous system. The palpebral reflex is lost at light planes of anesthesia in ruminants, so it is of little value during anesthesia of these species. Ophthalmic ointment should be applied to the eyes during anesthesia to prevent corneal injury. Body temperature is also an important parameter to monitor during anesthesia. Because of the tendency for anesthetized animals to lose body heat, supplemental heat sources a re often required to maintain adequate body temperature (100-102.5 F). ˚

Klp5_ekstraksi Dan Scaling Gigi

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