Materials & Restorations Dr S.E.Jabbarifar April 2009.

Materials & RestorationsMaterials & Restorations

Dr S.E.Jabbarifar Dr S.E.Jabbarifar

April 2009April 2009

Materials & RestorationsMaterials & Restorations

Back to basics !

Topics we will cover todayTopics we will cover today

Choice of materialsChoice of materials Their properties and usesTheir properties and uses Their advantages & disadvantagesTheir advantages & disadvantages

Why do restorations fail ?Why do restorations fail ?

Preserving tooth structurePreserving tooth structure

Repairing old fillingsRepairing old fillings

‘‘Temporary or Provisional’ restorationsTemporary or Provisional’ restorations

Choosing MaterialsChoosing Materials

Lets look at the pros & cons & uses of these Lets look at the pros & cons & uses of these direct restoratives:direct restoratives:

AmalgamAmalgam Composite resinsComposite resins Glass ionomerGlass ionomer Resin modified glass ionomerResin modified glass ionomer Poly acid modified resins (compomers)Poly acid modified resins (compomers) Calcium HydroxideCalcium Hydroxide Zinc Oxide & EugenolZinc Oxide & Eugenol

Choosing MaterialsChoosing Materials

Lets also look at the pros & cons & uses of Lets also look at the pros & cons & uses of these indirect restoratives:these indirect restoratives:

AcrylicAcrylic Chrome CobaltChrome Cobalt PorcelainPorcelain GoldGold

Why do Restorations Fail ?Why do Restorations Fail ?

Poor DesignPoor Design Wrong material usedWrong material used Inadequate thicknessInadequate thickness Margins in occlusionMargins in occlusion Built-in errors cause caries, eg. OverhangBuilt-in errors cause caries, eg. Overhang Inadequate retentionInadequate retention Porosity, poor packing or finishingPorosity, poor packing or finishing Pulpal damage, poor liningPulpal damage, poor lining

Why do Restorations FailWhy do Restorations Fail

Subsequent ChangesSubsequent Changes Recurrent cariesRecurrent caries Tooth fractureTooth fracture Attrition, abrasion, erosionAttrition, abrasion, erosion Pulpal necrosis Pulpal necrosis Tooth movement or loss causes increase or Tooth movement or loss causes increase or

changes to applied forceschanges to applied forces TraumaTrauma Exceed ‘working life’ or just wear outExceed ‘working life’ or just wear out

Preserving Tooth StructurePreserving Tooth Structure

Saving enamel Saving enamel

Minimal invasion dentistryMinimal invasion dentistry

ART techniqueART technique

Tunnel preps Tunnel preps

Adhesive dentistryAdhesive dentistry

Repairing old restorationsRepairing old restorations

Preserving Tooth StructurePreserving Tooth Structure

What are we trying to preserve?What are we trying to preserve?

Remember basic dental anatomyRemember basic dental anatomy

Outer EnamelOuter Enamel Hard, inflexibleHard, inflexible Prism structurePrism structure

Inner DentineInner Dentine Softer, more flexibleSofter, more flexible Vital structureVital structure

Preserving Tooth StructurePreserving Tooth Structure

Natural tooth structure is irreplaceable…. Natural tooth structure is irreplaceable…. ..

THINK HARD before you cut !THINK HARD before you cut !

Your replacement will never be as good Your replacement will never be as good The tooth will become weakerThe tooth will become weaker You are reducing the patient’s optionsYou are reducing the patient’s options There is more to go wrong in futureThere is more to go wrong in future You will probably be shortening the life of this tooth, and You will probably be shortening the life of this tooth, and

possibly the WHOLE dentition possibly the WHOLE dentition Practice true ‘Practice true ‘CONSERVATIVE’CONSERVATIVE’ DENTISTRY DENTISTRY

Preserving Tooth StructurePreserving Tooth Structure

Ideally, our restoration should Ideally, our restoration should mimic the natural tooth structuremimic the natural tooth structure

GIC replaces DentineGIC replaces Dentine Softer, more flexibleSofter, more flexible HydrophilicHydrophilic

Composite replaces EnamelComposite replaces Enamel Hard, inflexibleHard, inflexible hydrophobichydrophobic

Saving EnamelSaving Enamel

Where do the enamel prisms run ?Where do the enamel prisms run ?

Can we leave unsupported enamelCan we leave unsupported enamelIf so under what circumstances ?If so under what circumstances ?

Where can we preserve enamel ?Where can we preserve enamel ?

IncisallyIncisally Prevent class 3 turning to class 4 if possiblePrevent class 3 turning to class 4 if possible

Marginal ridgeMarginal ridge tunnel prep or sideways preptunnel prep or sideways prep

InterproximallyInterproximally Palatal approach to Class 3Palatal approach to Class 3

Just enough for matrix on Class 2Just enough for matrix on Class 2

GingivallyGingivally Conserve margin, keep supragingivalConserve margin, keep supragingival

Minimal Invasion DentistryMinimal Invasion Dentistry

Removal of enamel cariesRemoval of enamel cariesRemoval of soft, heavily infected dentineRemoval of soft, heavily infected dentineRestore with cariostatic, adhesive materialRestore with cariostatic, adhesive materialConsider ‘stepwise excavation’ & stabilizationConsider ‘stepwise excavation’ & stabilization

AVOIDAVOID Removing sound tooth structureRemoving sound tooth structure Exposure of pulpExposure of pulp

Remember the ART technique ?Remember the ART technique ?

Tunnel PrepTunnel Prep

Used for small Class 2 lesionsUsed for small Class 2 lesions

Contact point and marginal ridge are preservedContact point and marginal ridge are preserved

Tooth strength Tooth strength is retainedis retained

T shaped T shaped access cavityaccess cavity

Tunnel PrepTunnel Prep

T shaped accessT shaped accessRemove cariesRemove caries? matrix? matrixPack GICPack GICCompositeComposite

What about the What about the interproximalinterproximal enamel ?enamel ?

pulp

4546

Sideways PrepSideways Prep

Used for small Used for small Class 2 lesionsClass 2 lesions

Contact point Contact point and marginal and marginal ridge are ridge are preservedpreserved

Buccal Buccal access cavityaccess cavity

Adhesive DentistryAdhesive Dentistry

Eliminates the need to cut a retentive cavityEliminates the need to cut a retentive cavityCan support unsupported enamelCan support unsupported enamelReduces need for extensive crown or bridge prep.Reduces need for extensive crown or bridge prep. Eg -Maryland bridgeEg -Maryland bridge

Can eliminate preparation completelyCan eliminate preparation completely Eg –diastema closure, composite bridgeEg –diastema closure, composite bridge

Prolongs the life of restorations, thus reduces the Prolongs the life of restorations, thus reduces the number of re-cutsnumber of re-cutsREMEMBER- REMEMBER- fillings never get smaller when they are replaced !fillings never get smaller when they are replaced !

Repairing Old FillingsRepairing Old Fillings

fillings never get any smaller fillings never get any smaller

each time you replace them…..each time you replace them…..

So think before you drill and refill So think before you drill and refill

Can the old filling be repaired ?Can the old filling be repaired ? Is there hidden cariesIs there hidden caries Is the whole structure compromisedIs the whole structure compromised Are the aesthetics poorAre the aesthetics poor

If NO, consider repair rather than replacementIf NO, consider repair rather than replacement

Methods of Repairing Old FillingsMethods of Repairing Old Fillings

Smoothing & polishing marginsSmoothing & polishing marginsLocal patchingLocal patchingVeneeringVeneeringBonding, eg replacing lost cuspBonding, eg replacing lost cusp Mechanical retention, Mechanical retention,

Fresh surface cutting, retentive slots, etching, Fresh surface cutting, retentive slots, etching, sandblasting, pinssandblasting, pins

Chemical bondChemical bondSuitable adhesivesSuitable adhesives

Temporary or ProvisionalTemporary or Provisional

Temporary filling- short term onlyTemporary filling- short term only Prevents ingress of food and salivaPrevents ingress of food and saliva Protects vital tooth structuresProtects vital tooth structures Prevents tooth movementPrevents tooth movement Allows healing of painful toothAllows healing of painful tooth May need to be aesthetic (but not too good)May need to be aesthetic (but not too good)

Patient Patient mustmust understand the need to understand the need to return, and what will go wrong if they don’treturn, and what will go wrong if they don’t

Temporary or ProvisionalTemporary or Provisional

Provisional filling- medium termProvisional filling- medium term Awaiting healing, perio, pulp, endoAwaiting healing, perio, pulp, endo Checking occlusal load / wear patternsChecking occlusal load / wear patterns Testing appearanceTesting appearance Testing phoneticsTesting phonetics Testing functionTesting function Trying raised occlusal positionTrying raised occlusal position

Patient Patient mustmust understand the need to for regular understand the need to for regular review and reassessment, and what will go wrong if review and reassessment, and what will go wrong if their treatment is not completed.their treatment is not completed.

Temporary / Provisional MaterialsTemporary / Provisional MaterialsTemporary FillingTemporary Filling ZnO Eugenol,ZnO Eugenol, CavitCavit Temp Bond in acrylic or polycarbonate crownTemp Bond in acrylic or polycarbonate crown

Provisional fillingProvisional filling GICGIC AcrylicAcrylic CompositeComposite

Choose your words, temporary or provisionalChoose your words, temporary or provisional This will affect your patient’s expectationsThis will affect your patient’s expectations

Materials & RestorationsMaterials & Restorations

That's all folksThat's all folks

Thanks for listeningThanks for listening

You’ve been a great You’ve been a great audienceaudience