GIC AND CAVITIES FOR TOOTH GIC AND CAVITIES FOR TOOTH COLOURED RESTORATIVE COLOURED RESTORATIVE MATERIALSMATERIALS

DRDR WAN ZARIPAH WAN BAKARWAN ZARIPAH WAN BAKARPPPPSG, USMCKSG, USMCK

GLASS IONOMER CEMENTS (GIC)GLASS IONOMER CEMENTS (GIC)

Glass Glass ionomerionomer materialsmaterials

GIC is a waterGIC is a water--based material.based material.

Developed in Britain, and firstly described by Wilson and Kent iDeveloped in Britain, and firstly described by Wilson and Kent in 1972n 1972

Early versions for Class V abrasion lesion Early versions for Class V abrasion lesion –– lack of aesthetic and translucency.lack of aesthetic and translucency.

Conserve tooth structure, assist in Conserve tooth structure, assist in remineralisationremineralisation while maintaining aesthetic while maintaining aesthetic appeal.appeal.

Formed from the reaction of an ionFormed from the reaction of an ion--leachableleachable calcium calcium aluminosilicatealuminosilicate glass powder glass powder and a and a polyalkenoicpolyalkenoic acid.acid.““Glass Glass polyalkenoatepolyalkenoate cementscements””..

GLASSGLASS--IONOMER CEMENTIONOMER CEMENT

Types : Types : I) Conventional GICI) Conventional GIC2) RMGIC2) RMGIC

Conventional GIC Conventional GIC –– subgroups are glass subgroups are glass polyalkenoatespolyalkenoates and and glass glass polyphosphonatespolyphosphonates..

RMGIC RMGIC –– consist of the components of a glassconsist of the components of a glass--ionomer, modified ionomer, modified by the inclusion of a small quantity of addby the inclusion of a small quantity of additional resinitional resin--mostly HEMA.mostly HEMA.

-- set partly by an acidset partly by an acid--base reaction and partly by a base reaction and partly by a photochemical polymerization.photochemical polymerization.

Conventional GIC Conventional GIC –– chemically cured; acidchemically cured; acid--base reaction.base reaction.

RMGIC RMGIC –– consist of the components of a glassconsist of the components of a glass--ionomerionomer, modified , modified by the inclusion of a small quantity of addby the inclusion of a small quantity of additional resinitional resin--mostly HEMA.mostly HEMA.

-- set partly by an acidset partly by an acid--base reaction and partly by a base reaction and partly by a photochemical polymerization.photochemical polymerization.

COMPOSITIONCOMPOSITION

Powder: Calcium fluoroaluminosilicate glass which contain Powder: Calcium fluoroaluminosilicate glass which contain quartz, alumina, fluorite, cryolite, quartz, alumina, fluorite, cryolite, aluminiumaluminium fluoride, fluoride, aluminiumaluminium phosphate.phosphate.

-- Fused, quenched, ground and sieved to obtain particles in size Fused, quenched, ground and sieved to obtain particles in size 4 4 --5050µµm. m. Radiopacity Radiopacity –– lanthanum, strontium, barium, amalgam alloy, lanthanum, strontium, barium, amalgam alloy, ZnOZnO. . Abrasion resistance Abrasion resistance –– sintering metals such as silver or gold to glass sintering metals such as silver or gold to glass

particles. particles. FluorideFluorideColor Color –– titanium oxide up to 5%titanium oxide up to 5%

Liquid : 2:1 acrylicLiquid : 2:1 acrylic-- acidacid--itaconicitaconic--acid copolymer in water or a copolymer of acid copolymer in water or a copolymer of maleicmaleic acid and acrylic acid acid and acrylic acid –– 4040--55%55%

Tartaric acid Tartaric acid –– assist the extraction of ions from the glass powder, retain wassist the extraction of ions from the glass powder, retain wtime, sharpen setting time.time, sharpen setting time.

RMGIC RMGIC –– addition of resin mostly addition of resin mostly hydroxyethylhydroxyethyl methacrylatemethacrylate HEMA) HEMA) –– 1515--25%.25%.

Encapsulated GIC need to be mixed by crushing and agitatinEncapsulated GIC need to be mixed by crushing and agitating the capsule for a g the capsule for a prescribed time.prescribed time.

PROPERTIESPROPERTIES

Ability to bond chemically to mineralized tooth structures throuAbility to bond chemically to mineralized tooth structures through an iongh an ion--exchange exchange mechanism mechanism –– mountain formation.mountain formation.Release of fluoride.Release of fluoride.Ability to reabsorb fluoride ions and therefore react as a fluorAbility to reabsorb fluoride ions and therefore react as a fluorideidereservoir.reservoir.Limitations Limitations –– susceptibility to brittle fracturesusceptibility to brittle fracture

-- unable to withstand undue unable to withstand undue occlusalocclusal--incisalincisal loading.loading.

SETTING REACTIONSETTING REACTION

GIC: Ca polyacrylate chains form first followed by Al PA chainsRMGIC : HEMA (resin) included-additional chain superimposed over the acid-base reaction.

Fluoride release

CLASSIFICATIONCLASSIFICATION

Type I Type I –– lutinglutingType II Type II –– restorationrestoration

Type II.1 Type II.1 –– restorative aestheticrestorative aestheticType II.2 Type II.2 –– restorative reinforced. restorative reinforced.

Type III Type III –– lining or baselining or base

INDICATIONS FOR GICINDICATIONS FOR GICTemporary restorationsTemporary restorationsBase and linersBase and linersPermanent restorations Permanent restorations –– not load bearing areas.not load bearing areas.Core buildCore build--up for crowns.up for crowns.Cervical caries Cervical caries –– ““ Sandwich techniqueSandwich technique””Erosion lesionsErosion lesionsRoot cariesRoot cariesHypersensitive cavityHypersensitive cavityRampant cariesRampant cariesHigh caries riskHigh caries risk

STEPSSTEPS

Removal of caries and prepare the cavity surface as smooth as poRemoval of caries and prepare the cavity surface as smooth as possible.ssible.Clean tooth surface using a slurry of plain pumice and waterClean tooth surface using a slurry of plain pumice and waterCondition cavity with cavity conditioner Condition cavity with cavity conditioner –– 20% 20% polyacrylicpolyacrylic acid for 10 seconds.acid for 10 seconds.Wash vigorously with water spray for 30 seconds.Wash vigorously with water spray for 30 seconds.Dry for 5 seconds lightly but not dehydrate the surface.Dry for 5 seconds lightly but not dehydrate the surface.Application of the GIC materials with the help of celluloid striApplication of the GIC materials with the help of celluloid strip or matrix.p or matrix.Light cure for RMGIC.Light cure for RMGIC.

COMPOSITE RESINCOMPOSITE RESIN

Materials created when inorganic fillers are added to synthetic Materials created when inorganic fillers are added to synthetic resins.resins.Introduced commercially in midIntroduced commercially in mid--1960s.1960s.The use of intense visible light for polymerization developed inThe use of intense visible light for polymerization developed in the late the late 1970s.1970s.

Herculite - Kerr Filtek supreme

TYPESTYPES

Type 1 : Macrofilled composite resinType 1 : Macrofilled composite resin-- glass, quartz, ceramicglass, quartz, ceramic-- crushed, grinded, sieved to achieve splintercrushed, grinded, sieved to achieve splinter--shaped shaped

particles.particles.-- particle size 5particle size 5--3030µµmm

Type 2 : Microfilled CRType 2 : Microfilled CR-- amorphous silica diameter average 0.04amorphous silica diameter average 0.04µµm.m.

Type 3 : Hybrid CRType 3 : Hybrid CR-- particle size 0.5particle size 0.5--88µµmm

-- Lutz and Philips (1983)Lutz and Philips (1983)

Nanocomposite.Nanocomposite.-- particle size : nanometerparticle size : nanometer-- nanoparticles and nanoclustersnanoparticles and nanoclusters

a –macrofill; b-microfill, splintered prepolymerised particles;

a-microfill, homogenous; d-microfill, spherical prepolymerised particles;

e-microfil, agglomerated complexes; f- hybrid composite

COMPOSITIONCOMPOSITION

Matrix Matrix –– organic resin: diacrylates, bisorganic resin: diacrylates, bis--GMA, TEGDMA, EGDMA GMA, TEGDMA, EGDMA HEMA.HEMA.

Inorganic filler: glass, quartz, ceramic, silica powder.Inorganic filler: glass, quartz, ceramic, silica powder.-- 52% 52% -- 88%.(wt.)88%.(wt.)

Coupling agent Coupling agent –– silanesilane-- to unite the resin with the fillerto unite the resin with the filler

Initiator system Initiator system –– didi--ketone and tertiary amineketone and tertiary amine-- photosensitive photosensitive –– camphorquinone camphorquinone -- to activate the setting mechanismto activate the setting mechanism

Stabiliser (inhibitor)Stabiliser (inhibitor)Pigments.Pigments.

INDICATIONS FOR RESIN RESTORATIONSINDICATIONS FOR RESIN RESTORATIONS

InterproximalInterproximal ((ClCl. III) lesions of anterior teeth.. III) lesions of anterior teeth.Facial (Facial (ClCl. V) lesions of anterior teeth.. V) lesions of anterior teeth.Facial (Facial (ClCl. V) lesions of premolars.. V) lesions of premolars.Loss of Loss of incisalincisal angles (angles (ClCl. IV).. IV).Fracture of anterior teeth.Fracture of anterior teeth.Rebuilding of teeth to support castings.Rebuilding of teeth to support castings.Alternative to amalgam restorations.Alternative to amalgam restorations.-- ClCl. I, . I, ClCl. II, . II, ClCl. VI.. VI.

Direction of ShrinkageDirection of Shrinkage

Light activation occurs towards light- 60% occurs within 60 seconds- balance within 2 days

Chemical activation directed towards centre of restoration.- occurs slowly and evenly throughout restoration.

Incremental buildIncremental build--upup

Lamination technique – 2mm thickness.

Types of failure at the margin of a composite resin

POLYACIDPOLYACID--MODIFIED COMPOSITE RESINS MODIFIED COMPOSITE RESINS ––‘‘COMPOMERSCOMPOMERS’’

Contain resins and fillersContain resins and fillersResin Resin –– contains functional groups of polycarboxylic acid and contains functional groups of polycarboxylic acid and methacrylates combined in one molecule.methacrylates combined in one molecule.

-- carboxyl gps. for acidcarboxyl gps. for acid--base reaction (as in GIC)base reaction (as in GIC)-- methacrylic gps. for crossmethacrylic gps. for cross--linking (as in CR)linking (as in CR)Filler Filler –– fluoride containing glass.fluoride containing glass.EgEg. : . : DyractDyract, , CompoglassCompoglass

CLASS III CAVITYCLASS III CAVITY

Interproximal cavity.Interproximal cavity.When feasible, the preparation should be designed from the linguWhen feasible, the preparation should be designed from the lingual with al with the incisal part of the contact point is not removedthe incisal part of the contact point is not removed..

Moisture control and isolation Moisture control and isolation –– rubber dam, cottonrubber dam, cotton--role, saliva ejector.role, saliva ejector.Local anesthetic if needed.Local anesthetic if needed.Access Access –– palatal approach for esthetics.palatal approach for esthetics.

-- round bur size 1, jet 330.round bur size 1, jet 330.Caries removal Caries removal –– large SS bur # 2, 3large SS bur # 2, 3

-- spoon excavatorspoon excavatorOutline formOutline formResistance and retention form Resistance and retention form –– round bur # round bur # ¼¼ @ @ ½½Bevels Bevels –– margin trimmer, bur.margin trimmer, bur.Shade selectionShade selectionEtch, prime and bond (adhesive)Etch, prime and bond (adhesive)Celluloid strip insertionCelluloid strip insertionComposite resin placement Composite resin placement –– ‘‘press and pullpress and pull’’ technique.technique.Light cure.Light cure.Polishing Polishing –– white stone bur, soflex disc, rubber cup and diamond paste.white stone bur, soflex disc, rubber cup and diamond paste.

Burs: Jet 330, F20, L10, TC 169L.

CLASS IV CAVITYCLASS IV CAVITY

Cavity involving edge of incisal tip or fractured teeth.Cavity involving edge of incisal tip or fractured teeth.

CLASS V CAVITYCLASS V CAVITY

Cavities at Cavities at buccalbuccal or cervical surface of the tooth.or cervical surface of the tooth.Erosion cavity Erosion cavity –– superficial loss of dental hard tissue due to a superficial loss of dental hard tissue due to a

chemical process not involving bacterchemical process not involving bacteria.ia.AbfractionAbfraction –– erosive lesion due to excessive erosive lesion due to excessive buccalbuccal or lingualor lingual

occlusalocclusal load through either compression or tension inload through either compression or tension inthe cervical region of the tooth.the cervical region of the tooth.

CLASS II CAVITYCLASS II CAVITY

Other Tooth Coloured Restorations Suitable Cases

TUNNEL CAVITYTUNNEL CAVITY

SLOT CAVITYSLOT CAVITY

POLISHING BURSPOLISHING BURS

REFERENCESREFERENCES

Graham JM, Hume WR. Preservation and restoration of tooth Graham JM, Hume WR. Preservation and restoration of tooth structure. Mosby 1998.structure. Mosby 1998.Baum, Philips, lund. Textbook of operative dentistry. Second ed.Baum, Philips, lund. Textbook of operative dentistry. Second ed.; ; W.B. Saunders Company 1985.W.B. Saunders Company 1985.