Toothwear and Restoration of Toothwear and Restoration of Abrasion Lesions.Abrasion Lesions.

Dr. Jasmina Qamaruz ZamanDr. Jasmina Qamaruz ZamanDept of Operative DentistryDept of Operative Dentistry

Faculty of DentistryFaculty of DentistryUKMUKM

TERMINOLOGYTERMINOLOGY

ToothwearToothwear

Tooth surface loss (TSL)Tooth surface loss (TSL)

MECHANISMSMECHANISMS

1. Physiological (normal ageing)1. Physiological (normal ageing)

2. Pathological2. Pathologicala. Erosiona. Erosionb. Attritionb. Attritionc. Abrasionc. Abrasiond. Abfractiond. Abfractione. Multifactoriale. Multifactorial

EROSIONEROSION

Loss of tooth structureLoss of tooth structure

as a result of dissolutionas a result of dissolution

due to acidic chemical attack, due to acidic chemical attack,

other than those producedother than those produced

by intra-oral bacteria.by intra-oral bacteria.

EROSIONEROSION

A.A. Extrinsic sourceExtrinsic source

B.B. Intrinsic sourcesIntrinsic sources

EROSIONEROSION

A. Extrinsic source:A. Extrinsic source:1.1. BeveragesBeverages2.2. FoodsFoods3.3. Industrial processesIndustrial processes

B. Intrinsic sources:B. Intrinsic sources:1.1. Gastro-oesophageal reflux diseaseGastro-oesophageal reflux disease2.2. Eating disordersEating disorders3.3. Pregnancy morning sicknessPregnancy morning sickness

Erosion: Acid fumes

Erosion: ‘Cupping out’ of the dentine. This is because once exposed, dentine dissolves faster than enamel.

Erosion: Note the proud amalgam restorations. This is because the tooth has dissolved away from around the amalgam restoration.

Erosion: Gastric reflux – erosion on the palatal surfaces of posterior teeth.

ABRASIONABRASION

Loss of tooth structure Loss of tooth structure

by friction by friction

from an external agent.from an external agent.

ABRASIONABRASION

Etiology:Etiology:

1. Biting sewing thread1. Biting sewing thread

2. Pipe chewing2. Pipe chewing

3. Pen/pencil biting3. Pen/pencil biting

4. Tooth brushing4. Tooth brushing

Abrasion: over vigorous tooth brushing. ‘V’ shaped or saucer shaped notches at the cervical margins of teeth.

Abrasion: Pin chewing

Abrasion: sunflower seeds

ATTRITIONATTRITION

Tooth surface loss due to Tooth surface loss due to

tooth to tooth contact tooth to tooth contact

during function or parafunction.during function or parafunction.

ATTRITIONATTRITION

Etiology:Etiology:

1.1. Normal functional movement.Normal functional movement.

2.2. Bruxism.Bruxism.

Grinding of teeth during non-functional Grinding of teeth during non-functional movements of the jaw.movements of the jaw.

Attrition

Attrition – iatrogenic (from porcelain crowns)

ABFRACTIONABFRACTION

Loss of tooth structureLoss of tooth structure due to due to

flexural forces.flexural forces.

Teeth flex under Teeth flex under occlusal loads, occlusal loads, stresses are stresses are transmitted to the transmitted to the cervical area cervical area causing cervical causing cervical enamel rods to enamel rods to fracture and fracture and dislodge. dislodge.

With increased With increased flexural movements flexural movements V-shaped cavity V-shaped cavity appear.appear.

ABFRACTION

Often, the cause of tooth wear is multi-Often, the cause of tooth wear is multi-factorial ie. attrition, abrasion and erosion factorial ie. attrition, abrasion and erosion

occurs at the same time.occurs at the same time.

Multi-factorial

Multi-factorial

Restoration of Abrasion Restoration of Abrasion LesionsLesions

Materials and techniques used to Materials and techniques used to restore abrasion cavitiesrestore abrasion cavities

1.1. Glass Ionomer cement (Conventional / Glass Ionomer cement (Conventional / Resin Modified).Resin Modified).

2.2. Composite resinComposite resin3.3. Sandwich technique.Sandwich technique.

Glass Ionomer CementGlass Ionomer Cement

AdvantagesAdvantages Chemical adhesion to enamel and dentin (retentive Chemical adhesion to enamel and dentin (retentive

features in the cavity design is less important).features in the cavity design is less important). Release fluoride which prevent secondary caries.Release fluoride which prevent secondary caries.

Disadvantages Disadvantages (compared to composite resin)(compared to composite resin) Less estheticLess esthetic OpaqueOpaque

Benefits of Glass IonomerBenefits of Glass Ionomer

Chemical Bond to tooth - no bonding agent Chemical Bond to tooth - no bonding agent requiredrequired

Bonds to moist toothBonds to moist tooth Fluoride protectionFluoride protection Excellent marginal seal - no shrinkageExcellent marginal seal - no shrinkage Thermal expansion = toothThermal expansion = tooth Biocompatable - Ideal match for dentinBiocompatable - Ideal match for dentin

TechniqueTechnique1. Isolation (Rubber dam, cotton rolls, gingival 1. Isolation (Rubber dam, cotton rolls, gingival

retraction cord)retraction cord)

2. Select and adapt a metal cervical matrix.2. Select and adapt a metal cervical matrix.

3. Clean the cavity with pumice and water to 3. Clean the cavity with pumice and water to remove the acquired pellicle – wash and remove the acquired pellicle – wash and dry the cavity gently. dry the cavity gently.

TechniqueTechnique

4. Apply dentin conditioner for 4. Apply dentin conditioner for 20-3020-30 seconds – wash and seconds – wash and dry.dry.

5. Insert the GIC into the cavity – cover with the cervical 5. Insert the GIC into the cavity – cover with the cervical matrix, remove access material from around the matrix, remove access material from around the matrix.matrix.

6. Paint the surface of GIC with dentine bonding agent 6. Paint the surface of GIC with dentine bonding agent (DBA) immediately after removal of the matrix.(DBA) immediately after removal of the matrix.

7. Light cure for 20seconds to cure the DBA. However, if 7. Light cure for 20seconds to cure the DBA. However, if you are using RMGIC (Fuji II LC), you need to cure the you are using RMGIC (Fuji II LC), you need to cure the GIC and DBA for 40 seconds.GIC and DBA for 40 seconds.

TechniqueTechnique

8. Check the margins of the restoration, remove any 8. Check the margins of the restoration, remove any excess material using a pointed high speed bur.excess material using a pointed high speed bur.

9. Reapply the DBA and light cure for 20 seconds.9. Reapply the DBA and light cure for 20 seconds.

10. Do not polish the GIC restoration, polishing can 10. Do not polish the GIC restoration, polishing can only be done 24 hours later.only be done 24 hours later.

11. Polishing (after 24 hours) – use polishing discs: 11. Polishing (after 24 hours) – use polishing discs: from dark brown to light yellow.from dark brown to light yellow.This step is not necessary if you have used a This step is not necessary if you have used a cervical matrix.cervical matrix.

3 erosion / abrasion 3 erosion / abrasion cavities at the buccal cavities at the buccal surface of the teeth.surface of the teeth.

Scrub the surface with Scrub the surface with pumice and water – pumice and water – wash and dry.wash and dry.

Case 1

Translucent cervical matrix is Translucent cervical matrix is applied.applied.For the simulation exercise For the simulation exercise you will be using you will be using metal metal cervical matrixcervical matrix. Choose . Choose and adapt the matrix and adapt the matrix according to the tooth according to the tooth contour.contour.

Apply GIC into the cavity and immediately cover with the cervical matrix, remove access material. LIGHT CURE THE RMGIC FOR 20 SECONDS.

Case 1

Finished restoration, DBA was painted Finished restoration, DBA was painted onto the surface of the restoration onto the surface of the restoration and light cured for 20 seconds.and light cured for 20 seconds.

Check the margins, remove any Check the margins, remove any excess material using a pointed excess material using a pointed diamond bur.diamond bur.

Case 1

18 months later18 months later

3 years later3 years later

Case 1

Sharp angled lesion Sharp angled lesion along the gingival margin along the gingival margin under the old bridge.under the old bridge.

Gingival tissue removed from Gingival tissue removed from the lesion with the lesion with trichloracetic acid to trichloracetic acid to control bleeding.control bleeding.

Case 2

Dentin conditioner Dentin conditioner applied – use a brush applied – use a brush for this purpose.for this purpose.

GIC applied and the GIC applied and the matrix is placed.matrix is placed.

Case 2

A thin layer of resin bonding A thin layer of resin bonding agent was applied to seal the agent was applied to seal the surface against changes in surface against changes in water balance. water balance.

Further re-contouring and Further re-contouring and further coats of bonding further coats of bonding agent appliedagent applied

Case 2

The finished restoration 18 The finished restoration 18 years later.years later.

The finished restorationThe finished restoration

Case 2

Composite ResinComposite Resin

AdvantagesAdvantages

Excellent esthetics.Excellent esthetics. Micro-mechanical retention – does not have to Micro-mechanical retention – does not have to

rely on retention features of the cavity. rely on retention features of the cavity.

Composite ResinComposite Resin

Disadvantage:Disadvantage:1. Need excellent moisture control, otherwise: 1. Need excellent moisture control, otherwise:

a. retention is compromised – loss of a. retention is compromised – loss of restorationrestorationb. microleakage – sensitivity, secondary cariesb. microleakage – sensitivity, secondary caries

2. Polymerization shrinkage2. Polymerization shrinkageComposite is applied in thin increments Composite is applied in thin increments (layers).(layers).

What is it?What is it?It is a technique which requires the application It is a technique which requires the application of both composite restoration and Glass of both composite restoration and Glass Ionomer Cement in the same cavity.Ionomer Cement in the same cavity.

Sandwich TechniqueSandwich Technique

Sandwich Technique: Sandwich Technique: Why is it recommended?Why is it recommended?

Glass Ionomer Cement is Glass Ionomer Cement is applied to: applied to:

1.1. Replace the missing Replace the missing dentin.dentin.

2.2. Release fluoride Release fluoride (protect the pulp)(protect the pulp)

3.3. Increase retentionIncrease retention4.4. Reduce microleakage.Reduce microleakage.

Composite is applied to:Composite is applied to:• Replace Enamel and Replace Enamel and

Enhance esthetic.Enhance esthetic.• Provide a better Provide a better

polished surface.polished surface.• Increase abrasion Increase abrasion

resistance.resistance.

StepsSteps

1.1. Choose the appropriate shade of composite Choose the appropriate shade of composite resin for the tooth.resin for the tooth.

2.2. IsolationIsolation3.3. Follow the steps for GIC application.Follow the steps for GIC application.

Place just enough of the GIC to replace the Place just enough of the GIC to replace the missing dentine, keep the enamel free from missing dentine, keep the enamel free from GIC. GIC.

StepsSteps

4.4. i. Lamination of i. Lamination of Conventional GICConventional GIC::a. Etch the GIC & enamel for 15 seconds.a. Etch the GIC & enamel for 15 seconds.b. Wash and dry lightly.b. Wash and dry lightly.c. Apply DBA to GIC and enamel – light cure for c. Apply DBA to GIC and enamel – light cure for

20 seconds.20 seconds.d. Place the composite resin incrementally - light d. Place the composite resin incrementally - light

cure each increment for 20 seconds and the cure each increment for 20 seconds and the final increment for 40 seconds.final increment for 40 seconds. ..

StepsSteps

4.4. ii. Lamination of ii. Lamination of RMGICRMGIC::a. a. Etch the enamelEtch the enamel only for 15 seconds. only for 15 seconds. - It is - It is not necessary to etch the GICnot necessary to etch the GIC because it because it

contains HEMA (resin) which can bond to the contains HEMA (resin) which can bond to the resin in DBA.resin in DBA.

b. Apply DBA to GIC and enamel – light cure for b. Apply DBA to GIC and enamel – light cure for 20 seconds.20 seconds.

c. Place the composite resin incrementally – light c. Place the composite resin incrementally – light cure each increment for 20 seconds and the cure each increment for 20 seconds and the final increment for 40 seconds.final increment for 40 seconds.

StepsSteps

5.5. Polish the restoration using soflex discs.Polish the restoration using soflex discs.6.6. Apply DBA and light cure for 20 seconds.Apply DBA and light cure for 20 seconds.

ENAMEL DENTINE

CEJ

CASE 1

ENAMEL DENTINE

RMGICGIC/RMGIC

CR

OPEN SANDWICH TECHNIQUE

ENAMEL DENTINE

CASE 2

CEJ

ENAMEL DENTINE

CASE 2

CEJ

CR

GIC/RMGIC

CLOSED SANDWICH TECHNIQUE

Mixing Glass Ionomer CementMixing Glass Ionomer Cement

1.1. Hand mixHand mix

a.a. Dispense 1 scoop powder and 1 drop liquid.Dispense 1 scoop powder and 1 drop liquid.

b.b. Divide the powder into equal parts.Divide the powder into equal parts.

c.c. Mix in ½ of the powder into the liquid.Mix in ½ of the powder into the liquid.

By 10 seconds the first part of the powder should By 10 seconds the first part of the powder should be fully mixed.be fully mixed.

d.d. Draw in second half and complete the mixing.Draw in second half and complete the mixing.

By 25 seconds the mix should be complete.By 25 seconds the mix should be complete.

Mixing GlassMixing Glass Ionomer Cement Ionomer Cement

b. Depress plunger.b. Depress plunger.

2. Precapsulated2. Precapsulateda. Tap or shake the capsule to loosen a. Tap or shake the capsule to loosen

the powder.the powder.

c. Click once in capsule c. Click once in capsule applier to activate.applier to activate.

e. Click twice to prime capsule e. Click twice to prime capsule

then syringe.then syringe.

Any Questions?Any Questions?