MANAGEMENT OF MANAGEMENT OF MUTILATED TEETHMUTILATED TEETH

DEFINITIONDEFINITION

Mutilated tooth is that tooth which Mutilated tooth is that tooth which is grossly weakened and is grossly weakened and badly broken down where the badly broken down where the amount of remaining tooth amount of remaining tooth structure is less than the amount structure is less than the amount of tooth loss.of tooth loss.

Causes of MutilationCauses of Mutilation

B) Traumatic fractureB) Traumatic fracture

C) Recurrent caries C) Recurrent caries

A) Long standing caries

Causes of MutilationCauses of Mutilation

A) Long standing caries:A) Long standing caries:Factors that increase Dental Caries Factors that increase Dental Caries

Progression:Progression: Patients with enamel Patients with enamel

hypoplasia, hypocalcification.hypoplasia, hypocalcification. Patients with bad oral habits Patients with bad oral habits

(eating sweets,sticky food,…). (eating sweets,sticky food,…). Patients with bad oral Patients with bad oral

hygiene. hygiene.

B) Traumatic fractureMaybe due to Traffic accidentBicycle fallsBlows to the faceChewing hard objectsc) Recurrent cariesIt is considered the cause of mutilation to already placed restoration

Characteristics of Characteristics of mutilated teethmutilated teeth

1. Partial or complete loss of cusps.1. Partial or complete loss of cusps.

2. Loss of marginal ridges or 2. Loss of marginal ridges or crossing ridges.crossing ridges.

3. Loss of axial angles.3. Loss of axial angles.

4. Negative crown / root ratio, 4. Negative crown / root ratio, which which is normally 1:3.is normally 1:3.

Characteristics of Characteristics of mutilated teethmutilated teeth

5. Partial or complete loss of 5. Partial or complete loss of crown/root junction.crown/root junction.

6. Multiple cracks with an 6. Multiple cracks with an unlimited unlimited extent or extent or appearance of signs appearance of signs and and symptoms of cracked tooth symptoms of cracked tooth syndrome.syndrome.

SEQUALAE OF SEQUALAE OF MUTILATIONMUTILATION

1. Weakening of remaining 1. Weakening of remaining tooth tooth substance substance decrease retention decrease retention and and resistanceresistance

2. May endanger normal pulp 2. May endanger normal pulp physiology , periodontal physiology , periodontal

health health and restoration of and restoration of estheticsesthetics

SEQUALAE OF SEQUALAE OF MUTILATIONMUTILATION

3. Drifting or over eruption of teeth 3. Drifting or over eruption of teeth complicating restoration and complicating restoration and compromising successcompromising success

Examination and Examination and clinical assessment of clinical assessment of toothtooth

Patients with high caries incidence

Amalgam or full coverage2)Oral hygiene.Bad oral hygiene (amalgam)3) Periodontal status.4)The amount of remaining tooth

structure

5) Amount of forces to which 5) Amount of forces to which the the tooth is subjected.tooth is subjected.

6) Bad habits.6) Bad habits.

7) Mobility.7) Mobility.

8) Cracks.8) Cracks.

Restorative treatmentRestorative treatment. Anterior teeth :. Anterior teeth :

- - Resin composite. (complex Resin composite. (complex fracture and horizontal)fracture and horizontal)

- Porcelain laminate. (multiple - Porcelain laminate. (multiple fracture)fracture)

- Ceramic or porcelain fused to - Ceramic or porcelain fused to metal restorations.(loss of two metal restorations.(loss of two incisal angle together, multiple incisal angle together, multiple defect)defect)

Restorative treatmentRestorative treatment

II. Posterior teeth:II. Posterior teeth: Amalgam restorationAmalgam restoration Resin composite Resin composite Inlays or OnlaysInlays or Onlays Full coverage Full coverage

restoration restoration

CAVITY PREPARATION CAVITY PREPARATION FOR DIRECT FOR DIRECT RESTORATIONSRESTORATIONS

GENERAL RULESGENERAL RULES::

1)1) Remove all carious dentin and Remove all carious dentin and all undermined enamel.all undermined enamel.

2)2) The outline of all the cavity is The outline of all the cavity is extended into smooth extended into smooth

cleansable enamelcleansable enamel

AMALGAMAMALGAM : : Facial and lingual walls of the cavity Facial and lingual walls of the cavity

should converge occlusally with a should converge occlusally with a C.S.A. of 90 degrees .C.S.A. of 90 degrees .

Additional resistance and Additional resistance and retention meanretention mean

Capping cusps, Retention Capping cusps, Retention locks, Slots, Dentin locks, Slots, Dentin chambers and Pins.chambers and Pins.

CAPPING CUSPS:CAPPING CUSPS:

- Needed when caries is extensive and - Needed when caries is extensive and when the lingual or facial extension is when the lingual or facial extension is two third from a primary groove toward two third from a primary groove toward the cusp tip.the cusp tip.

- Functional cusps are reduced by 2mm - Functional cusps are reduced by 2mm minimumminimum

- Non functional cusps are reduced by - Non functional cusps are reduced by 1.5mm1.5mm

- Functional cusps are reduced by 2mm minimum- Non functional cusps are reduced by 1.5mm

- Roundation of any sharp external - Roundation of any sharp external corners is a must to reduce stress corners is a must to reduce stress concentration in the amalgam.concentration in the amalgam.

- - Disadvantage:Disadvantage: Reduction of the cusp significantly Reduction of the cusp significantly

reduce the retention form by reduce the retention form by decreasing the length of the decreasing the length of the longitudinal walls.longitudinal walls.

RETENTION LOCKS:RETENTION LOCKS:

-- wherever wherever possible, possible, retention locks in retention locks in dentin of the dentin of the axial walls are axial walls are are made by are made by using fissure bur.using fissure bur.

SLOTS:SLOTS:

- Slots can be prepared along the - Slots can be prepared along the gingival floor using an inverted gingival floor using an inverted cone bur.cone bur.

- Slots are placed 0.5 mm pulpal - Slots are placed 0.5 mm pulpal of the DEJ.of the DEJ.

- Slots are at least 0.5 mm in - Slots are at least 0.5 mm in depth and 1 or more mm in depth and 1 or more mm in length.length.

- - ADVANTAGES:ADVANTAGES: 1. Slot-retained amalgam is more 1. Slot-retained amalgam is more

retentive than pin-retained retentive than pin-retained amalgam.amalgam.

2. Slots are less likely to perforate 2. Slots are less likely to perforate the tooth.the tooth.

- - DISADVANTAGE:DISADVANTAGE: More tooth structure is More tooth structure is

removed removed preparing slots compared preparing slots compared with with pins.pins.

DENTIN CHAMBER:DENTIN CHAMBER:

- Called Amalgapin technique. - Called Amalgapin technique. - Dentin chambers are prepared in - Dentin chambers are prepared in

the floor of the cavity with the bur the floor of the cavity with the bur parallel to the external surface of the parallel to the external surface of the tooth.tooth.

- Depth is 2mm.- Depth is 2mm. - The junction between the pulpal floor - The junction between the pulpal floor

and the walls of the chamber is beveled and the walls of the chamber is beveled with round bur.with round bur.

- - DISADVANTAGES:DISADVANTAGES: 1. The potential of tooth 1. The potential of tooth

perforation is greater perforation is greater than with than with slots.slots.

2. Less retention than Slots 2. Less retention than Slots and and Pins.Pins.

Definition of pin-retained restorationIt may be defined as any restoration requiring the placement of one or more pins in the dentin to provide adequate resistance and retention forms.

Advantage1-conservation of tooth structure2- resistance and retention means3-economics

Disadvantage1- dentinal microfractures2- microleakage3- perforation

PINS:PINS:

- Types of pins:Types of pins:

1.Cemented pins.1.Cemented pins.

2. Self threading pins.2. Self threading pins.

3.Friction locked pins.3.Friction locked pins.

1. Cemented pins:1. Cemented pins:

-They are serrated-They are serrated -They are cemented by dental -They are cemented by dental

luting cement using lentulo spiral.luting cement using lentulo spiral. -Diameter of pinhole preparation is -Diameter of pinhole preparation is

0.0025 to 0.05mm larger than that 0.0025 to 0.05mm larger than that of pin.of pin.

-Pinholes are prepared at a depth of -Pinholes are prepared at a depth of 3-4 mm.3-4 mm.

- ADVANTAGES:ADVANTAGES:- 1.1.Require minimal access for Require minimal access for

insertion.insertion.- 2.2.Can be measured, cut. bent., Can be measured, cut. bent.,

trial fitted before cementation.trial fitted before cementation.- 3.3.Available in 3 diameters.Available in 3 diameters.- 4.4.No internal stresses upon No internal stresses upon

placement.placement.- 5.5.Can be used in non vital tooth Can be used in non vital tooth

and vital tooth.and vital tooth.

DISADVANTAGES:DISADVANTAGES:

1. Weak retention.1. Weak retention.

2. ZPC is irritant.2. ZPC is irritant.

3. Retention of the pins in dentin 3. Retention of the pins in dentin is proportional to the strength of is proportional to the strength of CementCement

Used and the length of pin into Used and the length of pin into holes.holes.

2. Self threading 2. Self threading pins(TMS)pins(TMS)- Available in three types:Available in three types:- 1.The regular type (3 lengths)1.The regular type (3 lengths)- Diameter 0.031”, Pinhole 0.027”Diameter 0.031”, Pinhole 0.027”- 2.The Minim type (2 lengths)2.The Minim type (2 lengths)- Diameter 0.024”, Pinhole 0.021”Diameter 0.024”, Pinhole 0.021”- 3.The Minikin type3.The Minikin type- Diameter 0.019”, Pinhole 0.017”Diameter 0.019”, Pinhole 0.017”- ( anterior restoration)( anterior restoration)-

-ADVANTAGES:-ADVANTAGES: 1.Strongest retention.1.Strongest retention. 2.No cementation complications.2.No cementation complications. 3.No pulp irritation.3.No pulp irritation. -DISADVANTAGES:-DISADVANTAGES: 1.Internal stresses.1.Internal stresses. 2.Restricted to available access 2.Restricted to available access

cavity.cavity. 3.Not used in non vital teeth.(Rely 3.Not used in non vital teeth.(Rely

on dentin viscoelasticity.)on dentin viscoelasticity.) 4.High cost.4.High cost.

3.Friction locked pins:3.Friction locked pins:

-They are smooth pins with -They are smooth pins with continuous spiral groove.continuous spiral groove.

-The pin diameter is 0.001” larger -The pin diameter is 0.001” larger than the twist drill.than the twist drill.

-The pinhole dept is 2-3mm.-The pinhole dept is 2-3mm.

--ADVANTAGES:ADVANTAGES: 1.Strong retention.1.Strong retention. 2.No cement complications.2.No cement complications. 3.Quiqest & easiest method.3.Quiqest & easiest method. 4.Provided in a variety of precut lengths.4.Provided in a variety of precut lengths. --DISADVANTAGES:DISADVANTAGES: 1.Internal stresses.1.Internal stresses. 2.Its use is restricted to available access 2.Its use is restricted to available access

for pin insertion cavity.for pin insertion cavity. 3.Not used in non vital teeth.(Rely 3.Not used in non vital teeth.(Rely

on dentin viscoelasticity.)on dentin viscoelasticity.)

Factors affecting pin Factors affecting pin retention in dentin & retention in dentin & amalgamamalgam

1.1. Type of pin.Type of pin.

2.2. 2. Surface characteristics.2. Surface characteristics.

3.3. 3. Orientation, Number and 3. Orientation, Number and Diameter.Diameter.

4.4. 4. Extention in dentin and 4. Extention in dentin and amalgam.amalgam.

Factors affecting pin Factors affecting pin placement:placement:1.1. Pin size:Pin size:2.2. Factors affecting selection of size:Factors affecting selection of size:3.3. a. amount of dentin available.a. amount of dentin available.4.4. b. amount of retention desired.b. amount of retention desired.5.5. 2.Pin number:2.Pin number:6.6. Factors deciding the number: Factors deciding the number: 7.7. a. amount of dentin available.a. amount of dentin available.8.8. b. amount of retention desiredb. amount of retention desired9.9. c. amount of missing tooth c. amount of missing tooth

structure.structure.10.10. d. size of the pin.d. size of the pin.11.11. ONE PIN PER MISSING AXIAL ANGLE ONE PIN PER MISSING AXIAL ANGLE

SHOULD BE USEDSHOULD BE USED

Consideration when Consideration when placing more than one placing more than one pin:pin:1.1. They should be placed at They should be placed at

different levels.different levels.

2.2. 2. Interpin distance;2. Interpin distance;

3.3. 3mm for the Minikin type3mm for the Minikin type

4.4. 5mm for the Minim type.5mm for the Minim type.

Possible problems Possible problems when using pinswhen using pins

1.1. Failure of restoration.Failure of restoration.

2.2. 2. Broken drills or pins.2. Broken drills or pins.

3.3. 3. Loose pins.3. Loose pins.

4.4. 4. Penetration into the pulp & 4. Penetration into the pulp & perforation of the external tooth perforation of the external tooth surface.surface.

PINS:PINS:

- Indicated in anterior teeth but - Indicated in anterior teeth but not used any more due to the not used any more due to the development in the adhesive development in the adhesive dentistry.dentistry.

- Teeth with little or no enamel to - Teeth with little or no enamel to etch that are ideally restored etch that are ideally restored with tooth colored crowns can with tooth colored crowns can be restored with pins only for be restored with pins only for economics and time restraints economics and time restraints

Cast inlay/ onlays :

Indications:1.It is the simplest of the cast restoration which is used to restore occlusal, gingival and proximal lesions.

2. Restoration of teeth which need cusp coverage.

3. Proximo - occlusal inlays is indicated for premolars and molars.

4.Class I inlays can be used to restore a moderately sized occlusal lesion.

5.Class III inlay is used to restore the distal surface of canine.

6.Class V inlays is used to restore severe abrasion or erosion.

Contraindications of cast Inlays :Patients with accumulation of plaque or recent history of caries here the full coverage crown is the treatment of choice.

Cast onlays:-Cast onlays:-Indications:Indications:1-1-MOD restoration with wide isthmuses.MOD restoration with wide isthmuses.

2-2- The use of inlay in mesio–occluso-distal lesions in premolars is questionable occlusal force on an inlay produces stresses along the sides of the restoration and at it’s base as the inlay pushes against the tooth structure surrounding it which could fracture the tooth so an The use of inlay in mesio–occluso-distal lesions in premolars is questionable occlusal force on an inlay produces stresses along the sides of the restoration and at it’s base as the inlay pushes against the tooth structure surrounding it which could fracture the tooth so an inlay must be modified to distribute the load evenly over a wide surface covering the occlusal surface with metal has minimized the damaging effect of stresses in an inter-coronal restoration.inlay must be modified to distribute the load evenly over a wide surface covering the occlusal surface with metal has minimized the damaging effect of stresses in an inter-coronal restoration.

Restorative materials used for cast restorations:Restorative materials used for cast restorations:

A)A) Gold alloys.Gold alloys.

B)B) Base metal alloys.Base metal alloys.

C)C) Sometimes for esthetic demands composite inlays may be usedSometimes for esthetic demands composite inlays may be used

Full coverage restorations:Full coverage restorations:Full cast restoration rebuilding the prepared abuement teeth it’s Full cast restoration rebuilding the prepared abuement teeth it’s

either.either.

A) Full metal crown:A) Full metal crown:Full metallic restoration rebuilding the prepared abutment teeth.Full metallic restoration rebuilding the prepared abutment teeth.

B) veneered crown:B) veneered crown:Full cast metal crown having the labial or buccal surface covered Full cast metal crown having the labial or buccal surface covered

with acrylic or porcelain facing.with acrylic or porcelain facing.

Indications of full coverage restoration:Indications of full coverage restoration: 1.1. Badly broken down teeth when no other type of restoration Badly broken down teeth when no other type of restoration

can be used.can be used.

2.2. Mutilated teeth with short Occluso-gingival height.Mutilated teeth with short Occluso-gingival height.

3.3. Mutilated teeth which need splinting for periodontal disease.Mutilated teeth which need splinting for periodontal disease.

4.4. Rotated , tilted and malposed teeth.Rotated , tilted and malposed teeth.

Reinforcement of endodontically treated teethReinforcement of endodontically treated teeththe pulpless teeth require different treatment from the tooth that still retains vitality.the pulpless teeth require different treatment from the tooth that still retains vitality.

l. l. The cast post and core:The cast post and core:

1.1. Single rooted teethSingle rooted teeth

2.2. Multi rooted teeth:Multi rooted teeth:

A) Straight rootedA) Straight rooted

B) Divergent rooted teethB) Divergent rooted teeth

ll. ll. Prefabricated posts:Prefabricated posts:

A)A) With amalgam core.With amalgam core.

B)B) Prefabricated posts with composite core.Prefabricated posts with composite core.

C. RESIN COMPOSITEC. RESIN COMPOSITE::

1.1. All enamel margins have All enamel margins have to be to be beveled to increase beveled to increase retention.retention.

2. Additional resistance and 2. Additional resistance and retention means: retention means:

Counter bevel, Reverse Counter bevel, Reverse bevel, bevel, Secondary flares, Skirts Secondary flares, Skirts and and Pins.Pins.

COUNTER BEVEL:COUNTER BEVEL:

- Prepared on non-functional - Prepared on non-functional cusps. cusps.

- The cusp is reduced 0.75mm.- The cusp is reduced 0.75mm. - A stone is placed with 30 - A stone is placed with 30

degrees angle on the outer degrees angle on the outer surface and the counter surface and the counter

bevel is bevel is placed.placed.

- Contraindicated in facial cusps - Contraindicated in facial cusps of upper premolars and first of upper premolars and first molars for esthetics.molars for esthetics.

So replaced by only blunting and So replaced by only blunting and smoothing of the enamel smoothing of the enamel margins.margins.

REVERSE BEVELREVERSE BEVEL

- Prepared on functional cusps.Prepared on functional cusps.- - Cusps are reduced by 1.5mm - Cusps are reduced by 1.5mm

then reverse bevel is placed with then reverse bevel is placed with chamfered margin on the chamfered margin on the external tooth surface.external tooth surface.

SECONDARY FLARES:SECONDARY FLARES:

- Made on the proximo-facial and - Made on the proximo-facial and proximo-lingual walls.proximo-lingual walls.

- Approach from the lingual - Approach from the lingual embrasure moving the stone embrasure moving the stone proximo-facially to place the proximo-facially to place the secondary lingual flare.secondary lingual flare.

- The same is done facially with - The same is done facially with opposite direction to place the opposite direction to place the secondary facial flare. secondary facial flare.

SKIRTS SKIRTS PREPARATION:PREPARATION: - These are thin extentions of the - These are thin extentions of the

facial or lingual proximal facial or lingual proximal margins that extend from the margins that extend from the secondary flare to end just secondary flare to end just beyond the line angle of the beyond the line angle of the tooth.tooth.

- Prepared entirely in enamel and - Prepared entirely in enamel and may involve very little dentin may involve very little dentin ATRAUMATIC.ATRAUMATIC.

- Never placed on the mesio-facial - Never placed on the mesio-facial wall of the upper premolars wall of the upper premolars

and and first molars for esthetics, so first molars for esthetics, so only secondary flares are done.only secondary flares are done.

- It allows bonded composite to - It allows bonded composite to brace the toothbrace the toothincrease increase resistance to fracture.resistance to fracture.

PINS:PINS:

- Indicated in anterior teeth but - Indicated in anterior teeth but not used anymore due to the not used anymore due to the development in the adhesive development in the adhesive dentistry.dentistry.

- Teeth with little or no enamel to - Teeth with little or no enamel to etch that are ideally restored etch that are ideally restored with tooth colored crowns can with tooth colored crowns can be restored with pins only for be restored with pins only for economics and time restraints economics and time restraints