Fixed Space Maintainers

By, By, Kavitha Shaji Paul 3rd  yr B.D.S

CONTENTS y

INTRODUCTION

CLASSIFICA TION TION  A DVA NT NT AGES & DISADV. B A NDS

y y y y

T Y PES PES

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R ECE ECENT ADVA NCES

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CONCLUSION G ALLERY 

CONTENTS y

INTRODUCTION

CLASSIFICA TION TION  A DVA NT NT AGES & DISADV. B A NDS

y y y y

T Y PES PES

y

R ECE ECENT ADVA NCES

y y

CONCLUSION G ALLERY 

INTRODUCTION

Space maintainers : are defined defined as appliances that prevent prevent loss of arch length length & which in turns guides the permanent permanent teeth into a correct correct position in the dental arch Fixed

Space Maintainers Maintainers::

are space maintainers maintain ers which are fitted onto the teeth. They can be unilateral or bilateral , functional functional or non functional functional , active or passive space maintainers maintainers that are are designed to be cemented on to the tooth.

CLASSIFICATION y



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 According to Hinrichson( 1962), CLASS I Non Functional Types

eg:Bar type,Loop type Functional T  ype eg:Pontic type,lingual type

CLASS II Cantilever T ype eg:distal shoe, Lingual arch

ADVANTAGES Easy manipulation  Jaw growth is not hampered Can be used in uncooperative patients Masticatory function is restored if pontics are placed Does not interfere with passive eruption of  abutment The bands are used without or with minimum tooth preparation

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DISADVANTAGES y y y y

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Elaborate instruments with expert skill is needed Decalcification of tooth under the bands may occur Increased risk of caries May be harmful to the abutment tooth due to development of torque causing breakage Supra eruption of the opposing tooth may occur if  pontics are used Pontics can interfere with eruption of abutment & may prevent eruption of succedaneous permanent teeth

BANDS Some bands used in fixed space maintainers are: Loop band, Tailored band, Preformed Seamless bands etc. Mostly made of precious metal, chrome alloy etc. R EQUIR EMENTS: 1.Should fit the contour of the tooth as close as possible & therefore enhance placement of attachment. 2.Material should resist tarnish & deformities 3.Cause no occlusal interference 4.Should not impinge the buccal mucosa or tongue y

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BA NDS:  Selection of band  trial & error procedure and continues until band can be seated with just finger pressure  Band Pusher is used to seat the band to a nearly ideal position.(finger rest has to be maintained)  Band Biter is used to achieve the final occlusolingual position.  Band is removed using a Band R emover.  Band is fixed on to the cast made of the patient.  The necessary attachments are then contoured on to the band. y

F ABRICA TION OF

TYPES I. o o

o

BA ND A ND LOOP It is a unilateral,passive fixed appliance The tooth distal to the extraction space is banded & a loop of thick stainless steel wire is soldered to it with its mesial end touching the tooth mesial to the extraction The loop is placed 1mm from the gingival surface & it should not be very wide so that it doesnt interfere with tongue and cheek movements

INDICATIONS & CONTRAINDICATIONS y

Indications:

1. In bilateral posterior tooth before the eruption of  permanent anteriors in the mandible 2. Also used when single tooth is missing in the posterior segment. y

Contraindications: 1. High caries activity  2. Marked Space Loss 3. More than one adjoining tooth missing

ADVANTAGES AND DISADVANTAGES OF BAND & LOOP

 ADVA NT AGES: It is economical & construction is simple Takes little chair side time(preformed bands) Can be adjusted to accommodate changing dentition

y

DISADVA NT AGES: Caries check & oral hygiene maintenance is difficult Loop may slip from the position and impinge on the gingiva ( occlusal rests)

y

MODIFICATIONS

OF BAND AND LOOP

 A. CROWN A ND LOOP:

are similar to the band & loop space maintainers in all respects except that a stainless steel crown is used for the abutment tooth Crown is used in preference   when 1. Highly carious 2. Exhibits marked hypoplasia 3. Pulpotomized y

They

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the toot

B.

R EVER SE CROWN

A ND LOOP: If the distal abutment tooth cannot be banded or crowned,a reverse crown &loop The mesial abutment tooth is banded or crowned and the loop is extended distally  This situation usually arises when the distal abutment tooth is not fully erupted

C. BA ND A ND BA R  SPACE MA INT A INER S: It is called as crown and bar space maintainer

Both the abutment teeth are bonded and a bar is placed between them  Adv : it is sturdier Disadv : may interfere  with the eruption of the permanent tooth as the bar is positioned on the centre of the ridge

II. LINGUAL ARCH SPACE MAINTAINER y

Most effective appliance for space maintenance in the lower arch.

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It

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Indicated

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is a bilateral,fixed or semi fixed,non functional,passive space maintainer. when there is bilateral loss of molars after eruption of permanent incisors. Helps in maintaining the arch perimeter by preventing both mesial drifting of the molars & lin ual colla se of the anterior teeth

ADVANTAGES & DISADVANTAGES OF LINGUAL ARCH SPACE MAINTAINER y

 Advantages 1.Less bulkier than removable sp. Maintainer 2.Maintaines space of more than one succedaneous tooth in the arch. 3.It allows free individual movement of teeth while maintaining space in the desired areas.

y

Disadvantages: 1.Arch wire may become embedded in the soft tissue. 2. W ire maybe distorted by masticatory forces.

MODIFICATIONS

 A. SEMI FIX ED OR  FIX ED R EMO VABLE TY PE OF

LINGUAL A RC   H Its similar to the fixed lingual arch,except that the wire is not soldered on to the lingual aspect of molars. Tubes are welded on to the bands into which the lingual arch wire fits. If theres no deep bite, it can be given on the maxillary  arch.

 A U-Loop can be incorporated in the arch wire to make it active,which aids in distalising the molars and in proclination. y

Spurs can be added to the arch at the distal end of canine to prevent distal collapse of the canine. y

III. NANCE PALATAL ARCH y

y

y

y

It

is a maxillary lingual arch that does not connect the anterior teeth. Its a bilateral,fixed,passive,non- Functional space maintainer. The first molars are banded and an arched wire extends from the palatal surface of one molar band to the other.  Anteriorly, it extends upto the rughae area and is embedded in an acrylic button.

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Indications: Used in maintaining the position of maxillary 1 st molar  when theres premature bilateral loss of primary teeth, with no loss of arch space and a favorable mixed dentition analysis.

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Advantage: If

premature loss is combined with oral habits like tongue thrusting, it is used to break the habit by  incorporation of spurs in the acrylic button. y

Disadvantages: The

acrylic button can cause soft tissue irritation & can get embedded in the tissue if the palatal tissue hypertrophies or if the appliance is distorted.

D. BONDED SPACE MA INT A INER  : In

this design,no band is placed  A loop that is bonded with resin on the buccal and lingual surfaces of both the abutment tooth The wire passes from one abutment to the other crossing the alveolar ridge.  Adv: 1.Economical & Simple construction 2.Takes little chair-side time (Preformed bands) 3.Can be adjusted to accommodate changing dentition.

IV. TRANSPALATAL ARCH

is a bilateral,fixed,passive , nonfunctional space maintainer. it is best indicated when one side of the arch is intact and several teeth are missing on the other side The molars (permanent)are banded and the arch  wire extends from the palatal aspect of the band to cross the midline transversely at right angles to the mid palatine raphe. It prevents the mesiolingual rotation of the permanent molar around the palatal root and prevents mesial movement of molars.

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It

V. DISTAL SHOE APPLIANCE: y y

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 Also called intra alveolar appliance. It a unilateral,fixed,non-functional and passsive space maintainer. It consists of a metal crown and a horizontal arm,which extends into the alveolus. The arm maintains leeway space for the second premolar and guides the eruption of perm 1 st molar. It requires regular follow-up.

INDICATIONS & CONTRAINDICATIONS y

y

Indications:

1. W hen theres premature loss of primary 2nd molar before eruption of perm 1st molar. 2. W hen only one tooth is lost on one quadrant as the strength of the appliance is limited. Contraindications: 1.Multiple missing teeth 2.Poor oral hygiene 3.Medically compromised patients(Cong. heart disease,SABE,kidney diseases,juvenile diabetes,etc.)

RECENT ADVANCEMENTS UNI VER SAL SPACE MA INT A INER : - It is a modified bonded space maintainer - It consists of a *stainless steel tubing *round retainer wire *solid steel foil pad base -  Adv: no bands or impressions are required - Can be completed with one appointment - Is esthetic & can be used on partially erupted tooth y

y

COICA N MODIFIED SPACE MA INT A INER :

- It is functional - It is used in case of partially erupted permanent molar and premature loss of  primary 2nd molar -  A wire is bonded on the permanent molar and the primary 1st molar -  A pontic is used to maintain space and function

ESTHETIC SPACE MA INT A INER  USING FIBER  R EINFOR CED COMPOSUTE(RIBBOND) - It is a fixed esthetic space maintainer using glass fiber reinforced composite -  Advantages: 1.Saves time & cost 2.Used in metal allergy  3.Easy to clean 4.No cast model required & thus no 2nd visiting - Disadvantage: 1.High failure rate(94%) 2.Can only be used for short periods y

FIX ED

CONCLUSION

I hereby conclude that fixed space maintainers are very effective in space maintenance especially in uncooperative patients

GALLERY

BIBLIOGRAPHY Textbook of  Orthodontics 

M S R  A NI Orthodontics Art and Science  S I BHALAJI Textbook of Pediatric Dentistry  S G DAMLE   THI R  Principles and practice of Pedodontics  A R A   A O Textbook of  Orthodontics  GUR KEER   A TH SINGH Textbook of  Orthodontics  GR   ABER ,VA NER SDAL & V IG Textbook of Pedodontics  SHOBHA TENDON Textbook of Pediatric Dentistry PINKHAM,CASAMASS IMO