DENTAL CEMENTS

DENTAL CEMENTSPresented by;Snehal SonarkarDepartment of conservative dentistry and endodonticsTerna Dental College.Nerul, Navi Mumbai.Content;IntroductionHistoryIdeal properties of dental cements Classification of cements

RDT & Pulpal responsePulp protecting agentsCavity varnishCalcium hydroxideZinc oxide eugenol cementFluoride releasing cementsSilicate cementZinc silicophosphate cementGlass ionomer cement

Luting agentsZinc phosphate cementZinc polycarboxylate cementResin cementsMiscellaneousMineral Trioxide AggregateBiodentine I Root BPProperties of cementsConclusion References

Introduction Variety of cements are used for various purpose.Different applications make varying demands onManipulative properties.working and setting time.resistance to mechanical breakdown and dissolution.

Restorative , endodontic, orthodontics, periodontics and other surgical fields of dentistry.The application of cements depends on various application5Materials are supplied powder/liquid form and set by acid-base reaction, but this is not universally true.

So, in dentistry word cement has been applied, traditionally to powder/ liquid materials which are mixed to a paste consistency set to a hardness, and used clinically to restore teeth and attach preformed restorations, in or on the teeth.

AD 1050 to 1122 - according to the Arabian author Rhazes.Carious teeth were filled with ground mastic, alum, and honey or other substances.Riviere (1589) mentioned Oil of cloves (eugenol) applicable to dental operations, but may have been used earlier (1562) by Ambroise Pare to alleviate toothache.Craigs Restorative dental materials. 12th ed History Period of mechanical improvement1860 Zinc oxychloride (filling and cementing medium).1879 Zinc phosphate was introduced1908 Silicate cement was introduced in US.Cruder forms were used in europe in late 1800.1947 direct filling methyl methacrylateJournal of History of Dentistry 2005;July, 53(2):63-72.1960-70s Pit & fissure sealant introduced.1970s - polycarboxylate1971 Wilson & kent introduced GIC.1993- Torabinejad introduced MTA2008 Prof. Abbot introduced Biodentine.Definition CementSubstance that hardens to act as a base, liner, filling material, or adhesive to bind devices and prostheses to tooth structure or to each other. (Phillips)

A non metallic material used for luting, filling permanent or temporary restorative purposes, made by mixing components into a plastic mass that sets or as an adherent sealer in attaching various dental restorations in or on the tooth. (Craig)Ideal Properties of DENTAL CEMENTSWell adapted to living dental tissuesNon- toxic and non-irritantAnticariogenic qualitiesLow viscosity and film thickness reach areas between restoration and tooth.Resistant against mastication forces and pulling forces formed through the effect of gummy foodsContemporary Permanent Luting Agents Used in Dentistry: A Literature ReviewEbru SMER, Yaln DEER(Int Dent Res 2011;1:26-31)6. Mechanical properties meet the requirements for particular application. 7. Sufficient light transparency.8. Heat insulation to protect living tooth from thermal effects.9. sufficient working time and be easy to manipulate.10. Bond to hard dental tissues.

Contemporary Permanent Luting Agents Used in Dentistry: A Literature Review Ebru SMER, Yaln DEER(Int Dent Res 2011;1:26-31)11. Long shelf-life. 12. Antibacterial property13. Biocompatible.14. Chemically compatible with pulp and restorative material.15. Should not discolor tooth and restorative material.16. Should stabilize or diminish dentin permeability.

Operative Dentistry: Modern theory and practice. MA Marzouk. 2004

CLASSIFICATIONAccording to PhillipsFluoride-Releasing Cements for Direct-Filling Restorations

Cements as Luting Agents

Agents for Pulp Protection

SilicateZinc SilicophosphateGlass ionomer

Zinc phopshateZOEZinc polycarboxylateGlass ionomerResin- modified glass ionomerCompomerResin cementsCavity varnishesCavity linersCement basesClassification..Phillips Science of dental material. 11th ed. 2002According to reaction Acid Base Reaction

Light / Chemical activated polymerization and acid base reaction

Light / Chemical activated polymerization Zinc Phosphate cementZinc polycarboxylate cementZinc oxide- eugenol cement Glass ionomer cementResin modified glass ionomer cement

CompomersResin cement.

Classification..Phillips Science of dental material. 11th ed. 2002According to ingredients & application By CraigWater based cementsApplication Glass and resin modified glass ionomer cementClass 5 restorationsRetention of alloy restorationsRetention of alumina or zirconia based all ceramic restorationRetention of orthodontic bandsProvisional restorationsZinc PolyacrylateRetention of alloy restorationsRetention of orthodontic bandsRetention of pediatric stainless steel crownZinc phosphateRetention of conventional restorationsRetention of orthodontic bandsProvisional restorationsClassification..Craigs Restorative dental material. 12th ed. 2006Resin-Based cementsApplication Composites and Adhesive resinsBonded conventional crowns and bridges, veneers, inlays, and onlaysBonded laboratory composites crowns and bridges, veneers, inlays, and onlays.Bonded posts and cores.Retention of provisional restorationsRetention of orthodontics bandsCompomers

Bonded conventional alloy based restoration Retention of alumina or zirconia-based all ceramic restoration.Retention of orthodontic bracketsHigh-strength basesClassification..Craigs Restorative dental material. 12th ed. 2006Oil-based cementsApplication Zinc Oxide eugenolHigh-strength basesProvisional restorationsRoot canal sealersGingival tissue packsSurgical dressingsNoneugenol-Zinc oxideProvisional restorationsRoot canal sealersGingival tissue packsSurgical dressingsClassification..Craigs Restorative dental material. 12th ed. 2006According to OBrien

OBrien classified dental cements by matrix bond typeClassification..OBrien Dental material and their selection. 3rd ed. 2003Type of matrix bondClass of cementFormulation PhosphateZinc phosphate

Zinc phosphateZinc phosphate fluorideZinc phosphate copper oxide/saltsZinc phosphate silver saltsZinc silico-phosphate

Zinc silicophosphateZinc silicophosphate mercury saltsPhenolateZinc oxide-eugenolZinc oxide-eugenolZinc oxide-eugenol polymerZinc oxide-eugenol EBA/alumina

Calcium hydroxidesalicylate

Calcium hydroxide salicylateClassification..OBrien Dental material and their selection. 3rd ed. 2003Type of matrix bondClass of cement

FormulationPolycarboxylateZinc polycarboxylateZinc polycarboxylateZinc polycarboxylate fluorideGlass ionomerCalcium aluminum polyalkenoateCalcium aluminum polyalkenoate polymethacrylateDimethacrylate Acrylic Poly (methyl methacrylate)Dimethacrylate unfilledDimethacrylate filledAdhesive4-METAPolycarboxylate & DimethacrylateHybrid ionomersSelf cured Light curedClassification..OBrien Dental material and their selection. 3rd ed. 2003According to SturdevantsTraditional ceramic dental cementAbbreviationsLiquid component Powder componentReaction product matrixUnmodified ZOEZOEEugenolZnOCrystalline zinc eugenolateResin reinforced ZOER-ZOEEugenolZnO, polymer, resinCrystalline zinc eugenolateEBA- modified ZOEZOE-EBAEugenol, EBAZnO, Al2O3, polymerCrystalline zinc eugenolateCrystalline zinc ethoxybenzoateZinc phosphateZPH3PO4, H2OZnOCrystalline tertiary zinc phosphateSilicateSCH3PO4, H2OF-Al-Silicate glassAmorphous silico phosphateZinc silicophosphateZSPH3PO4, H2OF-Al-Silicate glass, ZnOAmorphous silico phosphateCrystalline tertiary zinc phosphateClassification..Sturdevants Art and Science of dental materials. 5th ed. 2006Polymer based dental cementAbbreviationsLiquid component Powder componentReaction product matrixPolycarboxylatePCPAA, H2OZnOAmorphous zinc polyacrylate gelConventional GIGIPAA, H2O

F-Al-Silicate glassAmorphous aluminopolyacrylate gel

Resin modified GIRMGIPAA, H2O, water soluble monomers

F-Al-Silicate glass

Amorphous aluminopolyacrylate gel, cross linked polymer

CompomerCMMonomersF-Al-Silicate glass

Amorphous cross linked polymer, aluminolpolyacrylate gelComposite (or resin)CPMonomers Silicate glassAmorphous cross linked polymerSturdevants Art and Science of dental materials. 5th ed. 2006Donovan classified as;Conventional Zinc phosphate, Polycarboxylate, Glass Ionomer ContemporaryResin-modified glass ionomers, Resin basedDonovan TE, Cho GC. Contemporary evaluation of dental cements. Compend Contin Educ Dent 1999;20(3):197219. taken fromDental Cements for Definitive Luting: A Review and Practical ClinicalConsiderations. Edward E. Hill, Dent Clin N Am 51 (2007) 643658Classification..According to functionFunctionCementsFinal cementation of completed restorationsZinc phosphate, Zinc Silicophosphate, reinforced ZOE, Zinc polycarboxylate, Glass ionomerTemporary cementation of completed restorations or cementation of temporary restorationZOE, noneugenol ZOHigh strength basesZinc phosphate, reinforced ZOE, Zinc Polycarboxylate, Glass ionomerTemporary fillingsZinc phosphate, reinforced ZOE, Zinc PolycarboxylateLow strength basesZOE, Calcium hydroxideLinersCalcium hydroxide in suspensionVarnishes Resin in solventClassification of intermediary bases

VarnishesA solution of natural gum, synthetic resins, or rosins dissolved in a volatile solvent, such as acetone, ether, or chloroform. (Phillips)Liner Thin layer of cement, such as a calcium hydroxide suspension in an aqueous or resin carrier (after evaporation), used for protection of the pulp; certain glass ionomer cements that are used as an intermediate layer between tooth structure and composite restorative material are also considered liners. (Phillips)Operative Dentistry: Modern theory and practice. MA Marzouk. 2004SubbasesTherapeutic material placed in deep portions of cavityPosses specific pharmacological action.BaseA layer of insulating, sometimes medicated, cement placed in deep portion of the preparation to protect pulpal tissue from thermal and chemical injury.Operative Dentistry: Modern theory and practice. MA Marzouk. 2004Function of baseThe function of the cement base is to promote recovery of the injured pulp and to protect it against further insult. The base serves as a thermal insulator and replaces missing dentin when it is used under the metallic restoration.Galvanic shock and chemical irritation.Resist fracture under masticatory loads.Dentistry for the Child and Adolescent. RALPH E. McDONALD. 8th ed.Phillips Science Of Dental Materials. 11th ed.Pulp protectionChemical protectionElectrical protectionThermal protectionPulpal medicationMechanical protection

Sturdevants Art and Science of dental materials. 5th ed. 2006

Schematic view of need for pulpal protection.(Sturdevant 5th ed)

Schematic examples of use of liners and bases for amalgam restoration.A Shallow amalgam tooth preparation, varnish or sealer applied to walls.B Moderate depth tooth preparation liners may be placed for thermal protection and pulpal medicationC deep preparation light cured calcium hydroxide is placed in deepest region in which infected dentin was excavated. Base- glass ionomer.Sturdevants Art and Science of dental materials. 5th ed. 2006Remaining dentin thicknessImportance of maximizing the RDT beneath cavity preparations in reducing pulpal damage has long been established.Preserving the Vital Pulp in Operative Dentistry: 3. Thickness of Remaining cavity Dentine as a Key Mediator of Pulpal Injury and Repair Responses. PETER E. MURRAY, PHILIP J. LUMLEY AND ANTHONY J. SMITH. Dental Update May 2002Minimal cavity RDT that does not cause unequivocal pulp injury have been decreasing:Stanley (1984) - RDT of 2 mm.Pameijer, Stanley and Ecker (1991) RDT of 1 mm or more would protect the pulp tissue from the cytotoxic effects of luting processPreserving the Vital Pulp in Operative Dentistry: 3. Thickness of Remaining cavity Dentine as a Key Mediator of Pulpal Injury and Repair Responses. PETER E. MURRAY, PHILIP J. LUMLEY AND ANTHONY J. SMITH. Dental Update May 2002Pulp protecting agents..RDT 2mm)Moderate excavation (RDT 0.5-2mm)Deep Excavation (RDT unhealthy reparative reaction.Direct contact with pulp chemical necrosis.Operative Dentistry: Modern theory and practice. MA Marzouk. 2004Light cured calcium hydroxidePrisma VLC Dycal - Dentsply Caulk

COMPOSITIONCalcium Hydroxide; Barium Sulfate; Urethane Dimethacrylate Resin;photoinitiator; stabilizer; pigments

www.dentsplymea.comINDICATIONS Direct pulp cappingProtective barrier between restorative materials and deep vital dentin (indirect pulp capping).CONTRAINDICATIONS Patients who have a history of severe allergic reaction to methacrylate resins.www.dentsplymea.comSTEP-BY-STEP DIRECTIONSDirect Pulp Cappingcomplete cavity preparationRinse the cavity and exposure siteGently dry preparation with cotton pellet. Avoid desiccation.Liner directly on the exposed pulp and cavity dentin judged to be less than 1mm remaining thickness in a thin layer. www.dentsplymea.comMaterial thickness should be approximately 0.8mm-1mm.Light cure spectral output containing 470 nm. Minimum light output must be at least 300mW/cm2 exposure for at least 20 seconds. Remove any material excess from retention areas, enamel, and/or margins with a sharp spoon excavator or a bur.Pulp vitality assessed in next appointment

www.dentsplymea.comProperties of linersCalcium hydroxideZnO cementsLining deep cavities/ Direct pulp cappingIn deep cavities to retard penetration of acids and reduce discomfort to pulpAntibacterial actionPulp protecting agents..Zinc Oxide and Eugenol basedFormulated as;Powder and liquidTwo paste system

Craigs. Restorative Dental Material. 12th ed

Indication Temporary cementThermal insulating baseRoot canal fillingCOMPOSITION PowderFunctionGm(Phillips 7th ed)Weight(%)(Craig 12th ed)Zinc oxide70gm69Principal ingredientRosin28.529.3Reduce brittleness of set cementZinc stearate11PlasticizerZinc acetate0.50.7Improve strength of set cementSkinners Science of dental materials. 7th ed.Craigs restorative dental material. 12th edLiquid(Phillips 7th ed)

(Craig 12th ed)

Function Eugenol8585Eugenol with olive oil act as plasticizer.Olive oil15Formulation and uses by ADA specification no. 30TypesUsesType ITemporary cementationType IIPermanent cementationType IIITemporary filling material and thermal insulating baseType IVCavity linersPhillips Science Of Dental Materials. 11th ed.Powder Zinc hydroxide Zinc carbonate

Zinc oxide

Carbonate

Magnesium oxide 300C300- 500CPhillip s science of dental material. 7th ed.Manipulation of ZOEPowder - incorporated into dispensed amount of liquid until a suitable consistency is achieved for the operation.Considerable amount of powder - incorporated into the liquid by heavy spatulation with a stiff spatula.More powder - stronger the cement and the more viscous the mixed cement.Craigs. Restorative Dental Material. 11th edBulk of powder incorporated in liquid.P/L 4:1 or 6:1Initial step, mix is thoroughly spatulated, and a series of smaller amounts is then added until the mix is complete. mix is thoroughly kneaded with the spatula (a stiff bladed steel spatula is the most effective type).Craigs. Restorative Dental Material. 11th edSetting reactionSetting chelation reaction zinc eugenolate.

Craigs. Restorative Dental Material. 12th edTwo molecules of eugenol react with ZnO in the presence of water to form the chelate, zinc eugenolate. Excess zinc oxide is always used, so the set material consists of a matrix of amorphous zinc eugenolate that binds the unreacted zinc oxide particles together.

78Setting reaction - accelerated by increases in temperature or humidity.EBA also forms a chelate with zinc oxide, and its presence allows some crystalline zinc eugenolate to form, which provides additional strength. AcceleratorsRetardersWater, alcohol, glacial acetic acidGlycol/ glycerineCraigs. Restorative Dental Material. 12th edFactors affecting setting timeIncorporating chemical accelerators in mixReducing particle size.Increasing P/L.Increasing percentage of fillers.Increasing temperature/ humidity.Adding water to original mix.Introducing greater energy in mixing procedure.Operative Dentistry: Modern theory and practice. MA Marzouk. 2004Specification requiremment of ZOE and ZnO noneugenol cements

Craigs. Restorative Dental Material. 12th edOther propertiesLeast amount of shrinkage 0.1% by volume.CTE 11 ppm/C

Biological propertiesIn vivo and in vitro tests of HeLa cells, human skin fibroblasts, and bovine pulp tissue; endodontic fillings in dogs, monkeys, and rats; and implants in tibias and in subcutaneous connective tissues of animals.Conventional ZOE sealers generally elicit mild to moderate reactions, whereas several of the therapeutic sealers elicit severe reactions.Craigs. Restorative Dental Material. 12th ed83Biological propertiesLeast irritating to pulp-dentin organ.Create impervious layer to elements normally present in oral environment.Applied in 0.5mm thickness.Decreases hardness of very minimal thickness of underlying dentinCTE and thermal diffusivity- less then tooth structure. (0.25)Operative Dentistry: Modern theory and practice. MA Marzouk. 2004Bonding to compositesInhibitory effect of methoxyphenols such as eugenol on the polymerization of methacrylate resins is of clinical importance.

Eugenol is considered a free-radical scavenger(presence of the allyl group) Act as a degradative chain-transfer agent (i.e., when activated, it preferably undergoes primary radical termination, rather than propagation). Temporary cements containing eugenol may negatively affect the polymerization of methylmethacrylate used in provisional restorations. Craigs. Restorative Dental Material. 13th edNon-eugenol cementTNE-Temrex Non-Eugenol Temporary Cement(Temrex)Dentsply Integrity TemGripNon-Eugenol Temporary Cement(Morita)PowerTemp (kerr dental)

Composition Integrity TempGripOrganic acids; Zinc oxide; Methacrylates; Catalyst; Stabilizerwww.dentsply.esIndication Temporary cementation of provisional acrylic and composite indirect restorations.Provisional or trial cementation (limited time) of ceramic, porcelain, composite, PFM (porcelain fused to metal) and all metal crowns and bridges.Modified ZOEEBA alumina- modified cements provisional restorations.Has improved carvability prevented chipping during trimmingsymptomatic teeth without pulp exposure showed no symptoms.EBA low solubility in water, disintegrated and wore excessively in the mouth. Craigs. Restorative Dental Material. 12th edEBA and other chelate cementsApplication These materials have been usedcementation of inlays, crowns, and fixed partial denturesfor provisional restorationsbase or lining materials.EBA and other chelate cementsOBrien. Dental material and their selection. 3rd ed.(2002)CompositionEBA and other chelate cementsPowderLiquidZinc oxideAluminum oxide or other mineral fillers-20% to 30% . Polymeric reinforcing agents - poly(methylmethacrylate), may also be presentEthoxybenzoic acid - 50% to 66% with the remainder eugenol.

OBrien. Dental material and their selection. 3rd ed.(2002)Setting The setting mechanism has not been fully elucidated. It appears to involve chelate salt formation between the EBA, eugenol, and zinc oxide. The setting is accelerated by the same factors that are operative for zinc oxide-eugenol cements.

EBA and other chelate cementsOBrien. Dental material and their selection. 3rd ed.(2002)Manipulation Cement is dispensed according to the instructionskneaded for 30 seconds,and then stropped for 60 seconds to develop a creamy consistency. Oil of orange can be used to clean eugenol cements from instruments.

Craigs restorative dental material. 11th ed.PropertiesSetting time ; 7 and 13 minutes.The EBA cements show viscoelastic properties with very low strength and large plastic deformation at slow (0.1 mm/min) rates of deformation and at oral temperature (37C).Solubility similar to - polymer-reinforced zinc oxide-eugenol materials in distilled water, although loss of eugenol also occurs. The resistance to solubility in organic acids appears to be greater than that of the zinc phosphate cements. When exposed to moisture, greater oral dissolution occurs than for other cements. OBrien. Dental material and their selection. 3rd ed.(2002)Zinc oxide eugenol

FilmThickness(mm)Settingtime(min)Solubility(wt%)Compressive(MPa)Tensile(MPa)Modulusofelasticity

Unmodified25-35 2-101.5

2-25 1-2 -Polymerreinforced35-457-9 135-55 5-82-3EBA-alumina 40-60 7-13 155-70 3-63-6OBrien. Dental material and their selection. 3rd ed.(2002)Advantages and DisadvantagesAdvantages easy mixing, long working time, good flow characteristics, and low irritation to pulp. Strength and film thickness can be comparable to those of zinc phosphate cements.DisadvantagesCritical proportioning, hydrolytic breakdown in oral fluids, liability to plastic deformation, and poorer retention than zinc phosphate cements. Resin reinforced ZOEUsed cementing agents for crowns and fixed partial denturescavity liners and base materialsprovisional restorative materials.OBrien. Dental material and their selection. 3rd ed.(2002)PowderLiquid Zinc oxide- 10% to 40%

Eugenolnatural orsynthetic resins (eg, colophony [pine resin], poly[methyl methacrylate], polystyrene,or polycarbonate) together with accelerators.

accelerators - acetic acid, antimicrobial agents - thymol or 8-hydroxyquinoline.

OBrien. Dental material and their selection. 3rd ed.(2002)Manipulation More powder is required for a cementing mix than with other cements. The mixing pad or slab should be thoroughly dry. The powder is mixed into the liquid in small portions with vigorous spatulation until the correct amount has been incorporated. Adequate time should be allowed for setting without disturbance of the cement. Both powder and liquid containers should be kept closed and stored under dry conditions.OBrien. Dental material and their selection. 3rd ed.(2002)Properties Because of the presence of the resin, the solubility of these cements appears to be somewhat lower than that of zinc oxide-eugenol materials.OBrien. Dental material and their selection. 3rd ed.(2002)Advantages and DisadvantagesAdvantages Minimal biologic effects, good initial sealing properties, and adequate strength for final cementation of restorations.Disadvantages Lower strength, higher solubility, and higher disintegration compared to zinc phosphate cements; hydrolytic instability; and the softening and discoloration of some resin restorative materials.OBrien. Dental material and their selection. 3rd ed.(2002)Fluoride releasing dental cementsThese material have Low strength resin based composites and amalgam low stress areas.Temporary and intermediate restorations.

Use of dental cements began with silicate cement.

Phillips Science Of Dental Materials. 11th ed.Anticariogenic mechanism of fluoride: Increased acid resistance of enamelEnhancement of remineralization,Inhibition of carbohydrate metabolism by the acidogenic plaque microflora.Phillips Science Of Dental Materials. 11th ed.2. bound fluoride in the form fluorapatite and unboundfluoride as crystal deposits of calcium fluo~idefluoride inhibits carbohydrate metabolism byacidogenic plaque microflora.103Cements as luting agentsThe word luting implies the use of a moldable substance to seal a space or to cement two components together.Phillips Science Of Dental Materials. 11thed.Microscopic image of the abutment prosthesis interface

D voids generation Phillips Science Of Dental Materials. 11th ed.

A irregular surfaceB two surface pressed against each otherC continuous interface with third materialMain purpose of luting to seal and fill this d105Procedure for luting Placement of cementSeating the prosthesisRemoving excess cement.Placement of cement

Cement paste should coat Inner surface of the crown and extend slightly over the margin.The occlusal aspect of the tooth preparation must be free of voids - to ensure no air entrapment. If voids remain in the occlusal region excessive tensile stress in the ceramic and a greater risk for fracture. Phillips Science Of Dental Materials. 11th ed.Complete filling of crown is not advised;bubble entrapmentSeating time increasesIncreased pressreRemoval of excess cement requires more time107Seating Moderate finger pressure - displace excess cement.Marginal gap evaluated with explorer at three or more points.Patient is asked to bite on a piece of cotton roll to ensure complete seating.Phillips Science Of Dental Materials. 11th ed.Removal of excess cementBrittle state does not adhere to the surrounding surfaces, the tooth and the prosthesis removed after it sets. Zinc phosphate and ZOE cements.

Glass ionomer, zinc polycarboxylate, and resin cements adhere both chemically and/or physically surfaces can be coated separating medium to inhibit cement adherencePhillips Science Of Dental Materials. 11th ed.'Iype I GIG and dual-cure resincements indicate that once the prosthesis is seated, the cement should be allowed toset for 1.5 to 3 nlin after the completion of cement mixing, but before the excesscement is removed.109Mechanism of Retention Retained mechanical or chemicalCement fills the irregular crevice cement/prosthesis and cement/tooth exhibit a void-free sealed cement layer can resist shear stress acting along the interface

Mechanism through which dental cement provides mechanical retention of a gold inlay. Cement penetrates into irregularities in the tooth structure and the casting.Phillips Science Of Dental Materials. 11th ed.110Dislodgement of ProsthesisFixed prostheses can debond because of biological factors, physical reasons, or a combination of the two. Secondary caries forms the biological reason.Modes of failure;Fracture of cementLeakage along the interfacePhillips Science Of Dental Materials. 11th ed.Materials for lutingZinc phosphate cementZinc polycarboxylate cementResin cementsGlass ionomer cementsZOE

Zinc phosphateOldest - luting cementsCommercial namesHarvard cement

Introduced by PIERCE 1879.Temporary restorationLuting agentSupplied as powder and liquid form.Cements are classified according to the particle sizeType I fine grained 25 mType II medium particle size 40 mTextbook of Operative Dentistry. Vimal Sikri. 1st ed. 2006PowderCompositionWeight (%)Function ZnO 90.2Principal ingredientMgO8.2To reduce temperature of Calcination process SiO, 1.4inactive fillerBi203

0.1Impart a smoothness to the freshly mixed cement mass, in large amounts it may also lengthen the setting TimeMisc. BaO, Ba,S04, CaO0.1Tannin fluoride may be added to provide a source of fluoride ions in some products.Craigs Restorative dental materials. 12th ed Liquid CompositionWeight (%)H3P0,(free acid)

38.2H3P04 (combined withAl and Zn)16.2Al2.5Zn

7.1H20

36.0Craigs Restorative dental materials. 12th ed Manufacture of powderMain ingredients of powder are sintered at temperatures between 1000 C 1400 C.Then ground to powder.Particle size-Smaller the particle size faster set of the cement.Phillips Science Of Dental Materials. 11th ed.Setting reactionPOWDERPhosphoric acid attacks the surface of particles and release zinc ions.Zinc reacts with aluminium to form zinc alumino-phosphate gelLIQUIDThe set cement consist of unreacted zinc oxide particles in amorphous matrix of zinc aluminophosphate.Phillips Science Of Dental Materials. 11th ed.Mixing slabCombination of powder/ liquid is an exothermic reaction.Cooled slab 18-20CPowder/liquid ratioFilling 2.5:1Luting 1.5:1Textbook of Operative Dentistry. Vimal Sikri. 1st ed. 2006Care of the Liquid Exposure of zinc phosphate cement liquid humid atmosphere absorb waterExposure to dry air loss of water. addition of water more rapid reaction shorter setting time. loss of water from the liquid lengthened setting time.Tightly close bottle. Polyethylene squeeze bottles.Craigs Restorative dental materials. 11th ed Manipulation initially small portions of powder into the liquid,

minimal heat is liberated and dissipated.

Long, narrow-bladed stainless steel spatula

Spread the cement large area (control thetemperature of the mass and its setting time)

Craigs Restorative dental materials. 11th ed heat of the reaction is most effectively dissipatedwhen the cement is mixed over a largearea of the cooled slab. 121Manipulation of zinc phosphate

Skinners Science of Dental Materials. 7th ed. 1973Small increments at start partial neutralizationLater large increments in the middle of mixing periodFinally small increments are added.Mixing procedure begins (slow maturation) and ends (critical consistency) with small incrementsMixing 60-90seconds

Craigs Restorative dental materials. 11th ed Glass slab cooled in a refrigerator at 6C-10C. Amount of powder -frozen slab method is 50% to 75% more than with the normal procedures. Compressive and tensile strengths not significantly different.Incorporation of condensed moisture into the mix in the frozen slab method counteracts the higher powder/liquid ratio.

Craigs Restorative dental materials. 11th ed Frozen Slab MethodThe advantages of the frozen slab method are Increase in working time (4 to 11 minutes) of the mix on the slab.Shorter setting time (20% to 40% less) of the mix after placement into the mouth.Cementation of bridges with multiple pins.

Craigs Restorative dental materials. 11th ed Setting timeManufacturing processHigher sintering temperature - cement set slowlyPresence of water in liquidLarger particle size less rapid reaction decreased surface contact of powder and liquid.Skinners Science of Dental Materials. 7th ed. 1973Factors under the control of dentistLower temperature during mixing.Rate of addition of powder in liquid.Longer mixing time longer setting time.More liquid in ratio to powder slower setting time.Skinners Science of Dental Materials. 7th ed. 1973AcidityDuring the formation of zinc phosphate change in pH.3minutes after start of mixing pH 3.5.24- 48hours pH comes to neutrality.(6.6 6.8)7 28day pH is 6.9Thin mix both initial and 28days are approximately 0.5 unit lower than thick mixes.

Craigs Restorative dental materials. 11th ed Precautions include the use of resinous, film forming, cavity varnishes; calcium hydroxide and zinc oxide suspensions; ZOE or calcium hydroxide bases; and, more recently, dentin bonding agents.

Craigs Restorative dental materials. 11th ed Consistency

Two mixes of cement prepared with identical P/L Temperature of slab - 18CTemperature of slab 29.5CSkinners Science of Dental Materials. 7th ed. 1973Standard consistency is determined by Modified SLUMP test. (ADA specification no 8)LutingBaseRetain alloy restorationThermal and chemical insulationCement string from the slab on spatula 2-3cmHigher P/L Craigs Restorative dental materials. 11th ed The consistency obtained whenproper amount of powder is mixed with 0.5 cu cm of liquid so that disck, 30mm in diameteri sformed when pressed between 2 slabs under load of 120gm131Retention No adhesion between tooth structure and zinc phosphate cement.Mechanical retention.Thickness of film between inlay and tooth - thinnerSkinners Science of Dental Materials. 7th ed. 1973

Skinners Science of Dental Materials. 7th ed. 1973Strength Mixture of standard consistency consist of 1.4gm of powder and 0.5ml of liquid75 % of maximal strength attained during 1hour.

Skinners Science of Dental Materials. 7th ed. 1973Strength influenced by;Initial P/L Manner of mixing and handlingCompressive strength develops rapidly with luting consistency reaching 2/3rd of final strength within 1 hour.Craigs Restorative dental materials. 11th ed Solubility and Disintegration Cemented cast restoration, solubility of cement is important consideration.Thin line of cement is always exposed to oral fluid at marginsCement line thicker then 50 micrometers.ADA specification no 8Solubility immersed in distilled water for 24hrs should not exceed 0.20%.Skinners Science of Dental Materials. 7th ed. 1973Solubility of Zinc phosphate cement in solution of varying pH for 1 week.

Skinners Science of Dental Materials. 7th ed. 1973Dimensional Stability Cement exhibits shrinkage on hardening. Normal dimensional change properly mixed cement is brought into contact with water slight initial expansion,Expansion slight shrinkage on the order of 0.04% to 0.06% in 7 days.Craigs Restorative dental materials. 11th ed Thermal and Electrical ConductivityPrimary uses of zinc phosphate cement insulating base beneath metallic restorations. Presence of moisture not have a significant effect on the thermal conductivity of cementBut, moisture present under clinical conditions greatly reduces the good electrical insulating.Craigs Restorative dental materials. 11th ed BiocompatibilityCytotoxicity studiesZinc phosphate cements are cytotoxic immediately after mixing.After complete setting - almost no cell damage is seenImplantation studiesRats and guinea pigs showed that subcutaneous implanted zinc phosphate cements cause a pronounced inflammatory reaction immediately after mixing, which disappeared after a few weeksBiocompatibility of Dental Materials. Gottfried Schmalz,Dorthe Arenholt-Bindslev. 2009

Histopathological studiesWhen used as base is not a highly toxic material.Some displacement of odontoblast layer, and infiltrating inflammatory cells is countable, implying the presence of a moderate lesion.After 36 days - no signs of inflammation were present

Biocompatibility of Dental Materials. Gottfried Schmalz,Dorthe Arenholt-Bindslev. 2009

Application Zinc phosphate cement is used most commonlyluting permanent metal restorations base. Other applications include cementation of orthodontic bandsZinc polycarboxylateDeveloped - late 1960s. Zinc polyacrylate cements (or zinc polycarboxylate)Supplied as a powder and a liquidThe liquid is a water solution of polyacrylic acidMixed cement - Classified as pseudoplastic.OBrien. Dental Material and their Selection. 3rd ed.adhesive dentalcements that would combine the strength properties of the phosphate system with thebiologic acceptability of the zinc oxide- eugenol materials. 143On the basis of their composition, polycarboxylate cement are of three typesType I powder contains 90% zinc oxide and 10% magnesium oxide.Type II 30-40% alumina replaces zinc oxide powderType III polyacrylic acid is freeze dried and incorporated in powder.Textbook of Operative Dentistry. Vimal Sikri. 1st ed. 2006ApplicationsUsed for the cementation of cast alloy and porcelain Restorations Orthodontic bandsCavity liners or base materialsProvisional restorative materials.OBrien. Dental Material and their Selection. 3rd ed.Figure setting reactionIt occurs through the chelation of zinc of powder by the carboxylate group of polyacrylic acid. Adhesion to the tooth occurs through chelation of calcium.

Setting reactionSkinners Science of Dental Materials. 7th ed. 1973Zinc polycarboxylateManipulation P/L 1.5:1 (Weight) Phillips 1:2 to 2:1. (Craig)

Powder & liquid dispensed just before mixing.Mixed on non absorptive surface, such as a glass slabSkinners Science of Dental Materials. 7th ed. 1973Powder is rapidly incorporated into the liquid in large quantities.Mixing time 30-40sec.Loss of luster and stringy consistency setting reaction has progressed film thickness and proper wetting of tooth cannot take place.Skinners Science of Dental Materials. 7th ed. 1973

Typical consistency for water mix polycarboxylate and glass-ionomer cements. (OBrien 3rd ed)

Consistency of zinc polycarboxylate cement upon completion of 30 sec of mixing. If the mixing time is prolonged or the mix is allowed lo remain on the slab, the cement becomes dull in appearance and the material becomes tacky to the touch. Phillips Science Of Dental Materials. 11th ed.Mechanical propertiesValues Compressive strength55-67MPa (Phillips)DTS8-12 Mpa (OBrien)Modulus of elasticity6 Gpa (OBrien)Solubility0.1% to 0.6% (OBrien)Bond strengthEnamelDentin3.4 to 13 MPa, 2.1 MPa.Phillips Science Of Dental Materials. 11th ed.Solubility Low solubility in waterWhen exposed to organic acid pH 12 / AntibacterialCompressive Strength - 70~90 MpaExcellent Radiopacityhttp://www.veriodent.comProperties of dental cementsTypically in range of 25-150m. (Phillips)Determination of film thicknessWell mixed, non-granular1. Film thickness and consistencyCraigs Restorative dental materials. 12th ed Phillips Science of Dental Material. 11th ed.Factors affecting film thicknessParticle size of powderConcentration of powder in liquidViscosity of the liquidConsistency of the cementAmount of force during cementationManner in which force is applied in restorationCraigs Restorative dental materials. 12th ed Consistency Heavier Consistency more, Thickness is more Leading to less complete seating of the restoration.Craigs Restorative dental materials. 12th ed

Craigs Restorative dental materials. 12th ed 2. Viscosity Increase by increase in temperature and time.Prompt cementation after completion of mixing.Delay cause;Increase in film thicknessInsufficient seating of restoration.Craigs Restorative dental materials. 12th ed 3. Setting timeDetermined by ANSI/ADA Specification No. 96.A sufficient period of time after mixing To seat and finally adapt the margins of a casting, To seat and adjust a series of orthodontic bands, or To properly contour a base or provisional restorationCraigs Restorative dental materials. 12th ed American national standard instituteAmerican dental association196Adequate working time is expressed by proper net setting time, 2.5 and 8 minutes at a body temperature of 37C. 60 to 90 seconds consumed by mixing the powder and liquid.Net setting time is the time at which cement is sufficiently hard to resist indentation by standard indenter.Craigs Restorative dental materials. 12th ed 4. Strength Standard luting cement - 24-hour compressive strength of 70 MPa.

Craigs Restorative dental materials. 12th ed

Craigs Restorative dental materials. 12th ed 5. Solubility Water and oral fluidsWater based cements > resin/oil basedCraigs Restorative dental materials. 12th ed

Craigs Restorative dental materials. 12th ed

Bibliography Skinners Science Of Dental Materials. 7th ed.Craigs. Restorative Dental Material. 13th edCraigs. Restorative Dental Material. 12th edPhillips Science Of Dental Materials. 11th ed.OBrien dental material and their selection. 3rd ed.2002An atlas of glass ionomer cement. GJ Mount. 3rd ed. 2002.

Sturdevants art and science of dental materials. 4th ed.Sturdevants art and science of dental materials. 5th ed. Principles and practice of operative dentistry. Charbeneau. 2nd ed.1981.Textbook of Operative Dentistry. Vimal Sikri. 1st ed. 2006Biocompatibility of Dental Materials. Gottfried Schmalz, Dorthe Arenholt-Bindslev. 2009

Referred articlesJournal of History of Dentistry 2005;July, 53(2):63-72.

Contemporary Permanent Luting Agents Used in Dentistry: A Literature Review Ebru SMER1, Yaln DEER2(Int Dent Res 2011;1:26-31)

Preserving the Vital Pulp in Operative Dentistry: 3. Thickness of Remaining cavity Dentine as a Key Mediator of Pulpal Injury and Repair Responses. PETER E. MURRAY, PHILIP J. LUMLEY AND ANTHONY J. SMITH. Dental Update May 2002Torabinejad M, Watson TF and Ford TRP. Sealing Ability of a Mineral Trioxide Aggregate When Used As a Root End Filling Material. J endod 1993;19(12) 591-5.

Mohammadi &Dummer; properties and applications of calcium hydroxide in endodontics and dental traumatology. Int Endod J:2011;44,697-730.

Nair PNR, Duncan HF, Pitt Ford TR & Luder HU. Histological, ultrastructural and quantitative investigations on the response of healthy human pulps to experimental capping with mineral trioxide aggregate: a randomized controlled trial. Int Endod J. 2008:41;128150.

De Bruyne MAA, De Moor RJG. The use of glass ionomer cements in both conventional and surgical endodontics. Int Endod J.2004;37:91-104.AUJ Yap, SY Tham, LY Zhu, HK Lee. Short-Term Fluoride Release from Various Aesthetic Restorative Materials. Oper Dent 2002;27:259-266Reston EG and de Souza Costa CA. Scanning electron microscopy evaluation of the hard tissue barrier after pulp capping with calcium hydroxide, mineral trioxide aggregate (MTA) or ProRoot MTA. Aust Endod J 2009; 35: 7884

Roberts HS, Toth JM, Berzins DW, Charlton DG. Mineral trioxide aggregate material use in endodontic treatment: A review of the literature. Dental materials 24(2008) 149164.Sarkar NK, Caicedo R, Ritwik P, Moiseyeva R, and Kawashima I. Physicochemical Basis of the Biologic Properties of Mineral Trioxide Aggregate. J Endod 2005;31:2:97-100

THANK YOU EQUIA coat1. Class I restorations2. Non-stress bearing Class II restorations3. Stress bearing Class II restorations when isthmus is less than half ofintercuspal distance4. Intermediate restorative5. Class V and rootFuji IX GP extraFuji II LCFuji LINING LCFuji TRIAGE