Saliva

SALIVA Salivary secretions are protective in nature because they maintain the oral tissues in a physiologic state (Table 6-1). Saliva exerts a major infuence on plaque by mechanically cleansing the expose oral sur!aces" by bu#ering acis prouce by bacteria" an by controlling bacterial activity.

Antibacterial Factors Saliva contains numerous inorganic an organic !actors that infuence bacteria an their proucts in the oral environment. $norganic !actors inclue ions an gases" bicarbonate" soium" potassium" phosphates" calcium" fuories" ammonium" an carbon ioxie. %rganic !actors inclue lyso&yme" lacto!errin" myeloperoxiase" lactoperoxiase" an agglutinins such as glycoproteins" mucins" �'macroglobulins" bronectins" 11 an antiboies. Lysozyme is a hyrolytic en&yme that cleaves the lin*age bet+een structural components o! the glycopeptie muramic aci,containing region o! the cell +all o! certain bacteria in vitro. yso&yme +or*s on both gram-negative an gram-positive organisms /0 its targets inclue Veillonella species an Actinobaci an Actinobacillus llus actinomycetemcomitans actinomycetemcomitans.. $t probably repels certain transient bacterial invaers o! the mouth.  be bactericial to some strains o! Lactobacillus an Streptococcus2'"33 by preventing the accumulation o! lysine an glutamic aci" both o! +hich are essential !or bacterial gro+th. 4nother antibacterial ning is lacto!errin" +hich is e#ective against  Actinobacillus  Actinobacillus species.  Myeloperoxidase, an en&yme similar to salivary peroxiase" is release by leu*ocytes an is bactericial !or  Actinobacillus  Actinobacillus21 but has the ae e#ect o! inhibiting the attachment o!  Actinomyces strains to hyroxyapatite.16

Salivary Antibodies 4s +ith 57" saliva contains antiboies that are reactive +ith inigenous oral bacterial species. 4lthough immunoglobulins 5 ($g5) an 8 ($g8) are present" the preponerant immunoglobulin !oun in saliva is immunoglobulin A ($g4). 9o+ever" $g5 is more prevalent in 57 5 7.. 11 8ajor an minor salivary glans contribute all the secretory $g4 (s$g4) an lesser amounts o! $g5 an $g8. 57 contributes most o! the $g5" complement" an :8;s that in conjunction +ith $g5 or $g8 inactivate or opsoni&e bacteria. Salivary antiboies appear to be synthesi&e locally because they react +ith strains o! bacteria inigenous to the mouth but not +ith organisms characteristic o! the intestinal tract. 6"2 8any bacteria !oun in saliva have been sho+n to be coate +ith $g4" an the bacterial eposits on teeth contain both $g4 an $g5 in quantities greater than 1< o! their ry +eight.  $t has been sho+n that $g4 antiboies present in paroti saliva can inhibit the attachment o!  oral Streptococcus species to epithelial cells. "1'' 5ibbons et al6-2 suggeste that antiboies in secretions may impair the ability o!  bacteria to attach to mucosal or ental sur!aces.

Enzymes  The enzymes normally !oun in the saliva are erive !rom the salivary glans" bacteria" leu*ocytes" oral tissues" an ingeste substances0 the major en&yme is paroti amylase. ertain salivary en&ymes have been reporte in increase concentrations in perioontal isease= hyaluroniase an lipase" 1 �-glucuroniase an chonroitin sul!atase" >1 aspartate aminotrans!erase an al*aline phosphatase" 113 amino aci ecarboxylases" >1 catalase" peroxiase" an collagenase. 6/ :roteolytic en&ymes in the saliva are generate by both the host

an oral bacteria. These en&ymes have been recogni&e as contributors to the initiation an progression o! perioontal isease. >3" To combat these en&ymes" saliva contains antiproteases that inhibit cysteine proteases such as cathepsins 1 an antileu*oproteases that inhibit elastase. 2 4nother antiprotease" ientie as a tissue inhibitor o! matrix metalloproteinase (T$8:)" has been sho+n to inhibit the activity o! collagen-egraing en&ymes. '6 9igh-molecular-+eight mucinous glycoproteins in saliva bin specically to many plaque-!orming bacteria. The glycoproteinbacteria interactions !acilitate bacterial accumulation on the expose tooth sur!ace. "6-2"1'> The specicity o! these interactions has been emonstrate. The interbacterial matrix o! human plaque appears to contain polymers similar to salivary glycoproteins that may ai in maintaining the integrity o! plaque. $n aition" these glycoproteins selectively asorb to the hyroxyapatite to ma*e up part o! the acquire pellicle. %ther salivary glycoproteins inhibit the sorption o! some bacteria to the tooth sur!ace an to epithelial cells o! the oral mucosa. This activity appears to be associate +ith the glycoproteins that possess bloo group reactivity. 1""6"2"1'' 4nother e#ect o! mucin is the eletion o! bacterial cells !rom the oral cavity by aggregation +ith mucin-rich lms. 5lycoproteins an a glycolipi present on mammalian cell sur!aces appear to serve as receptors !or the attachment o! some viruses an bacteria. Thus the close similarity bet+een glycoproteins o!  salivary secretions an components o! the epithelial cell sur!ace suggests that the secretions can competitively inhibit antigen sorption an there!ore may limit pathologic alterations.

Salivary Bufers and Coagulation Factors  The maintenance o! physiologic hyrogen ion concentration (p9) at the mucosal epithelial cell sur!ace an the tooth sur!ace is an important !unction o! salivary bu#ers. Their primary e#ect has been stuie in relationship to ental caries. $n saliva the most important salivary bu#er is the bicarbonate,carbonic aci system.6 Saliva also contains coagulation !actors (!actors ?$$$" $@" an @0 plasma thromboplastin anteceent A:T4B0 9ageman !actor) that hasten bloo coagulation an protect +ouns !rom bacterial invasion. 66 4n active brinolytic en&yme may also be present.

Leukocytes $n aition to esquamate epithelial cells" the saliva contains all !orms o! leu*ocytes" o! +hich the principal cells are :8;s. The number o! :8;s varies !rom person to person at i#erent times o! the ay an is increase in gingivitis. :8;s reach the oral cavity by migrating through the lining o! the gingival sulcus. iving :8;s in saliva are sometimes re!erre to as orogranulocytes, an their rate o! migration into the oral cavity is terme the orogranulocytic migratory rate. Some investigators believe the rate o! migration correlates +ith the severity o! gingival infammation an is there!ore a reliable inex !or assessing gingivitis. 111

Role in eriodontal at!ology Saliva exerts a major infuence on plaque initiation" maturation" an metabolism. Salivary fo+ an composition also infuence calculus !ormation" perioontal isease" an caries. The removal o! the salivary glans in experimental animals signicantly increases the incience o! ental caries3 an perioontal isease >6 an elays +oun healing. 1/ $n humans" an increase in infammatory gingival iseases" ental caries" an rapi tooth estruction associate +ith cervical or cemental caries is partially a consequence o! ecrease salivary glan secretion (xerostomia). @erostomia may result !rom sialolithiasis"

sarcoiosis" SjCgrenDs synrome" 8i*ulic&Ds isease" irraiation" surgical removal o! the salivary glans" an other !actors (see hapters  an 3).

4$E $FE se*resi saliva pelinung i alam *arena mere*a mempertahan*an  jaringan rongga mulut alam *eaaan siologis (Tabel 6-1). 4ir liur memberi*an sebuah pengaruh besar paa pla* engan me*anis membersih*an ter*ena permu*aan lisan" oleh asam penyangga yang ihasil*an oleh ba*teri" an engan mengenali*an a*tivitas ba*teri. 7a*tor antiba*teri 4ir liur menganung banya* !a*tor organi* an anorgani* yang mempengaruhi ba*teri an prou* mere*a i ling*ungan mulut. 4norgani* !a*tor termasu* ion an gas" bi*arbonat" natrium" *alium" !os!at" *alsium" fuoria" amonium" an *arbon io*sia. !a*tor organi* termasu* liso&im" la*to!erin" myeloperoxiase" la*topero*siase" an aglutinin seperti gli*oprotein" mucins"

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

macroglobulins" bronectins" 11 an antiboi. yso&yme aalah en&im hiroliti* yang memotong hubungan antara *omponen stru*tural glycopeptie yang muramic menganung asam +ilayah ining sel ba*teri tertentu in vitro. *arya liso&im paa organisms/ *eua gram-negati! an gram positi!0 target termasu* spesies ?eillonella an 4ctinobacillus actinomycetemcomitans. 8ung*in repels penjajah ba*teri tertentu transien mouth. yang ba*terisia untu* beberapa strain actobacillus an Streptococcus2'"33 engan mencegah a*umulasi lisin an asam glutamat" yang *euanya penting bagi pertumbuhan ba*teri. antiba*teri lain

 Temuan ini la*to!erin" yang e!e*ti! terhaap 4ctinobacillus species. 8yeloperoxiase" en&im yang mirip engan saliva pero*siase" aalah irilis oleh leu*osit an ba*terisia untu* 4ctinobacillus21 tetapi memili*i e!e* tambahan menghambat perle*atan strain 4ctinomyces untu* hyroxyapatite.16 saliva 4ntiboi Seperti 57" air liur menganung antiboi yang rea*ti! engan spesies ba*teri mulut aat. 8es*ipun imunoglobulin 5 ($g5) an 8 ($g8) yang hair" imunoglobulin lebih besar itemu*an alam air liur aalah imunoglobulin 4 ($g4). ;amun" $g5 lebih la&im i 57.11 8ayor an minor *elenjar luah ber*ontribusi semua se*retori $g4 (s$g4) an jumlah yang lebih *ecil ari $g5 an $g8. 57 *ontribusi sebagian besar $g5" peleng*ap" an :8; yang alam hubungannya engan $g5 atau $g8 menona*ti!*an atau ba*teri opsoni&e. antiboi luah tampa*nya isintesis secara lo*al *arena mere*a berea*si engan strain ba*teri aat *e mulut tapi tia* engan organisme *ara*teristi* ari tract.6"2 usus Ganya* ba*teri itemu*an alam air liur telah terbu*ti ilapisi engan $g4" an eposito ba*teri paa gigi menganung $g4 an $g5 alam jumlah lebih besar ari 1< ari mere*a *ering +eight. Telah menunju**an bah+a $g4 antiboi hair alam air liur parotis apat menghambat perle*atan spesies Streptococcus oral untu* epitel cells."1'' 5ibbons et al6-2 menyaran*an bah+a antiboi alam se*resi apat merusa* *emampuan ba*teri untu* melampir*an mu*osa atau permu*aan gigi. en&im

Hn&im biasanya itemu*an alam air liur yang berasal ari luah *elenjar" ba*teri" leu*osit" jaringan mulut" an &at icerna0 en&im utama aalah amilase parotis. saliva tertentu en&im telah ilapor*an pening*atan *onsentrasi i perioontal :enya*it= hialuroniase an lipase" 1

-glucuroniase an



chonroitin sul!atase" >1 aminotrans!erase aspartat an basa !os!atase" 113 ecarboxylases asam amino" >1 *atalase" pero*siase" an collagenase.6/ en&im proteoliti* alam air liur yang ihasil*an oleh *eua host an ba*teri mulut. Hn&im ini telah ia*ui sebagai *ontributor untu* inisiasi an per*embangan isease.>3" perioontal Fntu* memerangi en&im ini" air liur menganung antiprotease yang menghambat protease sistein seperti cathepsins1 an antileu*oproteases yang menghambat elastase.2 antiprotease lain" iienti*asi sebagai inhibitor jaringan matri*s metaloproteinase (T$8:)" telah terbu*ti menghambat a*tivitas en&ymes.'6 *olagen-merenah*an  Tinggi berat mole*ul gli*oprotein mucinous alam air liur mengi*at *husus untu* banya* ba*teri pla* pembentu*. The glycoproteinbacteria intera*si mem!asilitasi a*umulasi ba*teri paa ter*ena gigi sur!ace."6-2"1'> Ie*hasan intera*si ini telah ibu*ti*an. 8atri*s interbacterial pla* manusia tampa*nya berisi polimer mirip engan gli*oprotein saliva yang apat membantu alam menjaga integritas pla*. Selain itu" ini gli*oprotein sele*ti! menyerap *e hiro*siapatit untu* membuat bagian ari peli*el. gli*oprotein saliva lainnya menghambat serapan ari beberapa ba*teri paa permu*aan gigi an epitel

sel-sel mu*osa mulut. Iegiatan ini tampa*nya ter*ait engan gli*oprotein yang memili*i golongan arah reactivity.1""6"2"1'' H!e* lain ari musin aalah penghapusan sel ba*teri ari rongga mulut oleh agregasi engan lm-*aya musin. 5li*oprotein an haiah glycolipi paa permu*aan sel mamalia muncul untu* melayani sebagai reseptor untu* lampiran ari beberapa virus an ba*teri. Jengan emi*ian *emiripan antara gli*oprotein ari se*resi saliva an *omponen ari permu*aan sel epitel menunju**an bah+a se*resi *ompetiti! apat menghambat antigen serapan an *arena itu apat membatasi perubahan patologis. Gu#er an 7a*tor Ioagulasi saliva :emeliharaan *onsentrasi ion hirogen siologis (:9) paa permu*aan sel epitel mu*osa an permu*aan gigi aalah !ungsi penting ari bu#er saliva. e!e* utama mere*a telah ipelajari alam hubungan engan *aries gigi. Jalam air liur paling penyangga saliva penting aalah asam bi*arbonat-*arbonat system.6 4ir liur juga menganung !a*tor *oagulasi (!a*tor ?$$$" $@" an @0 tromboplastin plasma yg i A:T4B0 7a*tor 9ageman) yang mempercepat pembe*uan arah an melinungi lu*a ari invasi ba*teri. 66 Hn&im brinoliti* a*ti! juga apat hair. leu*osit Selain sel epitel" air liur menganung semua bentu* leu*osit" ari mana sel-sel utama aalah :8;. $tu  jumlah :8; bervariasi ari orang *e orang paa +a*tu yang berbea hari an mening*at paa gingivitis. :8; mencapai rongga mulut

engan migrasi melalui selaput sul*us gingiva. 9iup :8; alam air liur *aang-*aang isebut sebagai orogranulocytes" an ting*at mere*a migrasi *e alam rongga mulut isebut orogranulocytic  Ting*at migrasi. Geberapa peneliti percaya laju migrasi ber*orelasi engan *eparahan infamasi gingiva an %leh *arena itu ine*s ianal*an untu* menilai gingivitis.111 :eran alam :atologi perioontal 4ir liur memberi*an pengaruh besar paa inisiasi pla*" pematangan" an metabolisme. aliran saliva an *omposisi juga mempengaruhi *al*ulus pembentu*an" penya*it perioontal" an *aries. :enghapusan luah *elenjar paa he+an percobaan secara signi*an mening*at*an *ejaian ari caries3 gigi an isease>6 perioontal an *eterlambatan lu*a healing.1/ :aa manusia" pening*atan penya*it gingiva infamasi" gigi *aries" an *ehancuran gigi yang cepat ter*ait engan servi*s atau *aries cemental sebagian *onse*uensi ari saliva menurun se*resi *elenjar (xerostomia). @erostomia apat ihasil*an ari sialolithiasis" sar*oiosis" sinrom SjCgren" 8i*ulic& :enya*it" iraiasi" operasi pengang*atan *elenjar luah" an !a*tor-!a*tor lain (lihat Gab  an 3).