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Dental acrylic resins / dental implant courses by Indian dental academy

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The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and
offering a wide range of dental certified courses in different formats.for more details please visit
www.indiandentalacademy.com

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Dental acrylic resins / dental implant courses by Indian dental academy

  1. 1. Dental acrylic resinsDental acrylic resins INDIAN DENTAL ACADEMYINDIAN DENTAL ACADEMY Leader in continuing DentalLeader in continuing Dental EducationEducation www.indiandentalacademy.comwww.indiandentalacademy.com
  2. 2. IntroductionIntroduction  Early fabrication of orthodontic appliances usedEarly fabrication of orthodontic appliances used vulcanized rubber, which was introduced byvulcanized rubber, which was introduced by Charles Goodyear in 1839Charles Goodyear in 1839  It was the material used by C. A. Hawley in hisIt was the material used by C. A. Hawley in his original removable retainer design. .original removable retainer design. .  Acrylic resins were introduced in 1936 in theAcrylic resins were introduced in 1936 in the monomer/polymer form.monomer/polymer form.  The autopolymerized or "cold-cured" resins,The autopolymerized or "cold-cured" resins, perfected in Germany during the 1940sperfected in Germany during the 1940s www.indiandentalacademy.comwww.indiandentalacademy.com
  3. 3. HistoryHistory  Before 1936, the materials used were vulcanite,Before 1936, the materials used were vulcanite, nitrocellulose, phenol formaldehyde, vinyl plastics &nitrocellulose, phenol formaldehyde, vinyl plastics & porcelain.porcelain. VULCANITE – contains rubber with 32% sulfur &VULCANITE – contains rubber with 32% sulfur & metallic oxides for color pigment.metallic oxides for color pigment. Advantages-Advantages-  non toxicnon toxic  non irritantnon irritant  excellent mechanical propertiesexcellent mechanical properties  material is sufficiently hard to polish.material is sufficiently hard to polish. www.indiandentalacademy.comwww.indiandentalacademy.com
  4. 4. Limitations-Limitations-  absorbs saliva & becomes unhygienic due to bacterialabsorbs saliva & becomes unhygienic due to bacterial proliferation,proliferation,  unpleasant odorunpleasant odor  poor esthetics due to opacity of the rubberpoor esthetics due to opacity of the rubber  Dimensional changes occur due to: thermal expansionDimensional changes occur due to: thermal expansion during heating in the vulcanizer & contraction of 2-4%during heating in the vulcanizer & contraction of 2-4% during addition of sulfur to rubberduring addition of sulfur to rubber NITROCELLULOSENITROCELLULOSE  Dimensionally stableDimensionally stable  Excessive warpageExcessive warpage  High water absorption poor color stabilityHigh water absorption poor color stability  Contains unpleasant tasting plasticizersContains unpleasant tasting plasticizers www.indiandentalacademy.comwww.indiandentalacademy.com
  5. 5. PHENOL FORMALDEHYDEPHENOL FORMALDEHYDE  Becomes discolored and unestheticBecomes discolored and unesthetic  Difficult to repairDifficult to repair PORCELAINPORCELAIN  Difficult to fabricateDifficult to fabricate  brittlebrittle www.indiandentalacademy.comwww.indiandentalacademy.com
  6. 6. ClassificationClassification  Based on thermal behaviourBased on thermal behaviour 1.1. ThermoplasticThermoplastic – eg. Polymethyl methacrylate, polyvinyl acrylics, polystyrene 2.2. Thermosetting – eg. Crosslinked polyThermosetting – eg. Crosslinked poly (methyl methacrylate), silicones(methyl methacrylate), silicones www.indiandentalacademy.comwww.indiandentalacademy.com
  7. 7. Ideal requirementsIdeal requirements 1.1. Biologic compatibilityBiologic compatibility - tasteless, Odorless,- tasteless, Odorless, Nontoxic, nonirritatingNontoxic, nonirritating  Completely insoluble in saliva or in any other fluidsCompletely insoluble in saliva or in any other fluids and should be impermeable to oral fluidsand should be impermeable to oral fluids  If used as a filling or cementing material, it shouldIf used as a filling or cementing material, it should set fairly rapidly and bond to tooth structure toset fairly rapidly and bond to tooth structure to prevent microbial ingrowth.prevent microbial ingrowth. 2.2. Physical PropertiesPhysical Properties -It should possess adequate-It should possess adequate strength and resiliencestrength and resilience  It should be resistant to biting or chewing forces,It should be resistant to biting or chewing forces, impact forces, and excessive wearimpact forces, and excessive wear  It should be dimensionally stable under all conditionsIt should be dimensionally stable under all conditions of service, including thermal changes and variationsof service, including thermal changes and variations in loading.in loading.  It should have a low specific gravity.It should have a low specific gravity. www.indiandentalacademy.comwww.indiandentalacademy.com
  8. 8. 3. Manipulation3. Manipulation-It should not produce toxic fumes or-It should not produce toxic fumes or dust during handling and manipulation.dust during handling and manipulation.  It should be easy to mix, insert, shape, and cure, andIt should be easy to mix, insert, shape, and cure, and it must have a relatively short setting time and beit must have a relatively short setting time and be insensitive to variations in these handlinginsensitive to variations in these handling procedurestheproceduresthe  The final product should be easy to polish, and inThe final product should be easy to polish, and in case of unavoidable breakage, it should be possiblecase of unavoidable breakage, it should be possible to repair the resin easily and efficientlyto repair the resin easily and efficiently 4.4. Aesthetic Properties-Aesthetic Properties- it should exhibit sufficientit should exhibit sufficient translucencytranslucency  It should be capable of being tinted or pigmentedIt should be capable of being tinted or pigmented 5.5. Economic ConsiderationsEconomic Considerations 6.6. Chemical StabilityChemical Stabilitywww.indiandentalacademy.comwww.indiandentalacademy.com
  9. 9. UsesUses  Dentures (bases, liners, andDentures (bases, liners, and  Artificial teethArtificial teeth  Cavity-filling materials ("composites")Cavity-filling materials ("composites")  Equipment (mixing bowls)Equipment (mixing bowls)  Cements (resin-based)Cements (resin-based)  Orthodontic & pedodontic appliancesOrthodontic & pedodontic appliances  SealantsSealants  Impression materialsImpression materials  Crown & bridge facingsCrown & bridge facings  Maxillofacial prosthesis (obturators for cleft palate)Maxillofacial prosthesis (obturators for cleft palate)  Inlay & post core patternsInlay & post core patterns  DiesDies  Temporary crowns & bridgesTemporary crowns & bridges  Athletic mouth protectorsAthletic mouth protectors  Impression traysImpression trays  Splints & stentsSplints & stents  ModelsModels www.indiandentalacademy.comwww.indiandentalacademy.com
  10. 10. FUNDAMENTAL NATURE OFFUNDAMENTAL NATURE OF POLYMERSPOLYMERS  Polymer- Chemical compound consisting of largePolymer- Chemical compound consisting of large organic molecules formed by the union of manyorganic molecules formed by the union of many repeating smaller monomer units.repeating smaller monomer units.  Polymerization-Chemical reaction in which monomersPolymerization-Chemical reaction in which monomers of a low molecular weight are con­verted into chains ofof a low molecular weight are con­verted into chains of polymers with a high molecular weight:polymers with a high molecular weight: PolymerizationPolymerization  Monomer + Monomer + MonomerMonomer + Monomer + Monomer Mer - Mer - Mer - Mer –Mer - Mer - Mer - Mer –www.indiandentalacademy.comwww.indiandentalacademy.com
  11. 11. Chain length & molecular weightChain length & molecular weight  The longer the chain length,The longer the chain length, the more difficult it is tothe more difficult it is to distort the polymericdistort the polymeric material, and thus suchmaterial, and thus such properties as rigidity,properties as rigidity, strength and the meltingstrength and the melting temperature increase withtemperature increase with the chain lengththe chain length  Consider the analogyConsider the analogy between the behavior of abetween the behavior of a polymer molecular chainspolymer molecular chains and a plate of spaghetti.and a plate of spaghetti. www.indiandentalacademy.comwww.indiandentalacademy.com
  12. 12. Branching and Cross-Branching and Cross- LinkingLinking www.indiandentalacademy.comwww.indiandentalacademy.com
  13. 13. Copolymer StructuresCopolymer Structures  Random copolymerRandom copolymer -ABBABABAAABAAAABABBBBABAAAABABAB-ABBABABAAABAAAABABBBBABAAAABABAB B ...B ...  Block copolymer -...Block copolymer -... AAAAABBBBBBBAAAABBBBBBBAAABBBAAAAAAAABBBBBBBAAAABBBBBBBAAABBBAAA A …A …  Graft or branched copolymer...Graft or branched copolymer... ….AAAAAAAAAAAAAA ….….AAAAAAAAAAAAAA …. B BB B B BB B B BB B www.indiandentalacademy.comwww.indiandentalacademy.com
  14. 14. Molecular OrganizationMolecular Organization www.indiandentalacademy.comwww.indiandentalacademy.com
  15. 15. PHYSICAL PROPERTIES OFPHYSICAL PROPERTIES OF POLYMERSPOLYMERS Deformation and recoveryDeformation and recovery  PlasticPlastic deformation is irreversible and results indeformation is irreversible and results in a new permanent shapea new permanent shape  ElasticElastic deformation is reversible and will bedeformation is reversible and will be completely recovered when the stress iscompletely recovered when the stress is eliminated.eliminated.  ViscoelasticViscoelastic deformation results in a combinationdeformation results in a combination of elastic and plastic strain but recovery of onlyof elastic and plastic strain but recovery of only elastic strain occurs as the stress is decreased.elastic strain occurs as the stress is decreased. www.indiandentalacademy.comwww.indiandentalacademy.com
  16. 16. Rheometric PropertiesRheometric Properties  Rheometry, orRheometry, or flowflow behaviorbehavior  Plastic flowPlastic flow  Elastic recoveryElastic recovery www.indiandentalacademy.comwww.indiandentalacademy.com
  17. 17.  The following characteristics describe the generalThe following characteristics describe the general nature of polymers:nature of polymers:  The longer the chains (the higher the molecularThe longer the chains (the higher the molecular weight), the more slowly a polymer dissolves.weight), the more slowly a polymer dissolves.  Polymers tend toPolymers tend to absorbabsorb a solvent, swell, and soften,a solvent, swell, and soften, rather than dissolverather than dissolve  Cross-linking prevents complete chain separation andCross-linking prevents complete chain separation and retards dissolutionretards dissolution  Highly cross-linked polymers cannot be dissolved.Highly cross-linked polymers cannot be dissolved.  Elastomers swell more than plastics.Elastomers swell more than plastics.  A small amount of swelling of dental polymeric devicesA small amount of swelling of dental polymeric devices can have undesirable results on the fit of prostheses.can have undesirable results on the fit of prostheses.  Absorbed molecules (e.g., water) spread polymerAbsorbed molecules (e.g., water) spread polymer chains apart and facilitate slip between chains. Thischains apart and facilitate slip between chains. This lubricating effect is calledlubricating effect is called plasticization.plasticization. www.indiandentalacademy.comwww.indiandentalacademy.com
  18. 18.  Cross-linkage provides a sufficient number ofCross-linkage provides a sufficient number of bridges between linear macromolecules to form abridges between linear macromolecules to form a three-dimensional network that decreases waterthree-dimensional network that decreases water sorption, decreases solubility, and increases thesorption, decreases solubility, and increases the strength and rigidity of the resin.strength and rigidity of the resin.  Plasticizers are often added to resins to reducePlasticizers are often added to resins to reduce their softening or fusion temperatures.their softening or fusion temperatures.  A plasticizer acts to partially neutralize secondaryA plasticizer acts to partially neutralize secondary bonds or intermolecular forces that normallybonds or intermolecular forces that normally prevent the resin molecules from slipping past oneprevent the resin molecules from slipping past one another when the material is stressed.another when the material is stressed.  External plasticizerExternal plasticizer  Internal plasticiserInternal plasticiserwww.indiandentalacademy.comwww.indiandentalacademy.com
  19. 19. CHEMISTRY OFCHEMISTRY OF POLYMERIZATIONPOLYMERIZATION Monomers may be joined via one of twoMonomers may be joined via one of two types of reaction:types of reaction: additionaddition polymerizationpolymerization  step-growthstep-growth or condensationor condensation polymerizationpolymerization www.indiandentalacademy.comwww.indiandentalacademy.com
  20. 20. Addition polymerizationAddition polymerization  Four distinct stages in the addition polymerization chainFour distinct stages in the addition polymerization chain reaction process: induc­tion, propagation, chain transfer,reaction process: induc­tion, propagation, chain transfer, and termination.and termination.  Induction. Two processes control the induction stage:Induction. Two processes control the induction stage: activation and initiationactivation and initiation  ActivationActivation R-R + external energy 2 R·R-R + external energy 2 R·  RequisitesRequisites  presence of an unsaturated group, that is, apresence of an unsaturated group, that is, a double bond,double bond, as well as a source of freeas well as a source of free radicals.radicals. www.indiandentalacademy.comwww.indiandentalacademy.com
  21. 21. InitiationInitiation www.indiandentalacademy.comwww.indiandentalacademy.com
  22. 22. PropagationPropagation RH2 C-CH2 • + H2 C=CH2 RH2 C-CH2 -H2 C-CH2 • RH2 C-CH2 -H2 C-CH2 • + H2 C=CH2 RH2 C- (CH2 - H 2 Ch -CH2 •.. etc.www.indiandentalacademy.comwww.indiandentalacademy.com
  23. 23. Chain TransferChain Transfer www.indiandentalacademy.comwww.indiandentalacademy.com
  24. 24. TerminationTermination www.indiandentalacademy.comwww.indiandentalacademy.com
  25. 25. Inhibition of AdditionInhibition of Addition PolymerizationPolymerization www.indiandentalacademy.comwww.indiandentalacademy.com
  26. 26. Step growth PolymerizationStep growth Polymerization  In step-growth polymerization, a linear chain ofIn step-growth polymerization, a linear chain of repeating mer units is obtained by the stepwiserepeating mer units is obtained by the stepwise intermolecular condensation or addition of theintermolecular condensation or addition of the reactive groups in whichreactive groups in which bifunctionalbifunctional or trifunctionalor trifunctional monomers are all simultaneously activatedmonomers are all simultaneously activated  For example:For example: HO-(Silicone)-OH + n HO-(Silicone)-OHHO-(Silicone)-OH + n HO-(Silicone)-OH HO-(Silicone)-(O-Silicone) n-OH+ n H20HO-(Silicone)-(O-Silicone) n-OH+ n H20 www.indiandentalacademy.comwww.indiandentalacademy.com
  27. 27. COPOLYMERIZATIONCOPOLYMERIZATION www.indiandentalacademy.comwww.indiandentalacademy.com
  28. 28. Multifunctional MethacrylateMultifunctional Methacrylate and Acrylate Resinsand Acrylate Resins  To quantify the efficiency of polymer­ization and cross-To quantify the efficiency of polymer­ization and cross- linking,the ratio, R, of unreacted methacrylate grouplinking,the ratio, R, of unreacted methacrylate group before & after polymerization.before & after polymerization.  TheThe degree of conversion,degree of conversion, expressed in percentage ofexpressed in percentage of consumed methyl methacrylate groups, can be deter­consumed methyl methacrylate groups, can be deter­ mined from the formulamined from the formula  (1 - R) x 100 = degree of conversion(1 - R) x 100 = degree of conversion www.indiandentalacademy.comwww.indiandentalacademy.com
  29. 29. Acrylic ResinsAcrylic Resins  The acrylic resins are derivatives of ethylene andThe acrylic resins are derivatives of ethylene and contain a vinyl (-C=C­-) in their structural formula:contain a vinyl (-C=C­-) in their structural formula:  There are two acrylic resin series that are of dentalThere are two acrylic resin series that are of dental interest.interest.  Acrylic acid CH2=CHCOOHAcrylic acid CH2=CHCOOH  methacrylic acid CH2=C(CH3)COOHmethacrylic acid CH2=C(CH3)COOH CH2=C (CH3) -CH2-C (CH3)-CH2-C (CH3)-CH2=C (CH3) -CH2-C (CH3)-CH2-C (CH3)- COORCOOR COORCOOR COORCOORwww.indiandentalacademy.comwww.indiandentalacademy.com
  30. 30. HEAT-ACTIVATED DENTUREHEAT-ACTIVATED DENTURE BASE RESINSBASE RESINS powder & liquidpowder & liquid Gels - sheets & cakesGels - sheets & cakes Commercial names- stellon (DPI), LucitoneCommercial names- stellon (DPI), Lucitone (Bayer), Travelon (Dentsply)(Bayer), Travelon (Dentsply) www.indiandentalacademy.comwww.indiandentalacademy.com
  31. 31. CompositionComposition liquidliquid  Methyl methacrylateMethyl methacrylate  Dibutyl phthalateDibutyl phthalate  GlycoldimethacrylateGlycoldimethacrylate  HydroquinoneHydroquinone PowderPowder  Poly(methyl methacrylate)Poly(methyl methacrylate)  Benzoyl peroxideBenzoyl peroxide  Compounds of mercuric oxide, cadmium sulfideCompounds of mercuric oxide, cadmium sulfide  Zinc or titanium oxideZinc or titanium oxide  Dibytyl phthalateDibytyl phthalate  Glass fibers or beadsGlass fibers or beads www.indiandentalacademy.comwww.indiandentalacademy.com
  32. 32. Methyl methacrylateMethyl methacrylate  Methyl methacrylate is aMethyl methacrylate is a transparent liquid at roomtransparent liquid at room temperature with the followingtemperature with the following physical properties:physical properties:  Molecular weight = 100Molecular weight = 100  Melting point = -48° CMelting point = -48° C  Boiling point = 100.8° C (noteBoiling point = 100.8° C (note how close this is to the boilinghow close this is to the boiling point of water)point of water)  Density = 0.945 g/mL at 20° CDensity = 0.945 g/mL at 20° C  Heat of polymerization = 12.9Heat of polymerization = 12.9 kcal/molkcal/mol CH3CH3 // H2C=CH2C=C C=OC=O // OO CH3CH3 www.indiandentalacademy.comwww.indiandentalacademy.com
  33. 33. Poly (Methyl Methacrylate)Poly (Methyl Methacrylate)  Poly (methyl methacrylate) is a transparent resin ofPoly (methyl methacrylate) is a transparent resin of remarkable clarityremarkable clarity  It is a hard resin with a Knoop hardness number of 18It is a hard resin with a Knoop hardness number of 18 to 20.to 20.  Tensile strength approximately 60 MPaTensile strength approximately 60 MPa  Density of 1.19 g/cm3Density of 1.19 g/cm3  Modulus of elasticity approximately 2.4 GPa (2400Modulus of elasticity approximately 2.4 GPa (2400 MPa).MPa).  Extremely stableExtremely stable  It is chemically stable to heat and 1250 CIt is chemically stable to heat and 1250 C  Above 1250 depolymerization takes place.Above 1250 depolymerization takes place.  At approximately 4500 C, 90% of the polymerAt approximately 4500 C, 90% of the polymer depolymerizes to form the monomerdepolymerizes to form the monomer www.indiandentalacademy.comwww.indiandentalacademy.com
  34. 34. Polymerization reactionPolymerization reaction  Powder + liquidPowder + liquid (polymer + initiator) (monomer+ inhibitor)(polymer + initiator) (monomer+ inhibitor) + heat+ heat Polymer + heatPolymer + heat  Techiques – compression moulding technique &Techiques – compression moulding technique & injection moulding techniqueinjection moulding technique www.indiandentalacademy.comwww.indiandentalacademy.com
  35. 35. Seperating mediaSeperating media TypesTypes o TinfoilTinfoil o Cellulose lacquersCellulose lacquers o Solution of alginated compoundSolution of alginated compound o Calcium oleateCalcium oleate o Soft soapsSoft soaps o Sodium silicateSodium silicate o starchesstarches www.indiandentalacademy.comwww.indiandentalacademy.com
  36. 36. Sodium alginate solutionSodium alginate solution Most commonly usedMost commonly used Water solubleWater soluble Rects with calcium of plaster or stone toRects with calcium of plaster or stone to form a film of insoluble calcium alginateform a film of insoluble calcium alginate Composition- 2% sodium alginate inComposition- 2% sodium alginate in water, glycerin, alcohol, sodium phosphatewater, glycerin, alcohol, sodium phosphate & preservatives& preservatives www.indiandentalacademy.comwww.indiandentalacademy.com
  37. 37. Mixing of powder & liquidMixing of powder & liquid  Polymer monomer proportion = 3:1 by volume orPolymer monomer proportion = 3:1 by volume or 2:1 by weight2:1 by weight  If too much monomer- greater polymerizationIf too much monomer- greater polymerization shrinkage, more time before packing, porosityshrinkage, more time before packing, porosity may occur.may occur.  If too little monomer- granular cured acrylic,If too little monomer- granular cured acrylic, inhomogeneous mix may not fuse into ainhomogeneous mix may not fuse into a continuous unit.continuous unit. www.indiandentalacademy.comwww.indiandentalacademy.com
  38. 38. Physical stages after mixingPhysical stages after mixing Stage I- Wet Sand Stage:Stage I- Wet Sand Stage: The polymer gradually settlesThe polymer gradually settles into the monomer forming a fluid, incoherent mass.into the monomer forming a fluid, incoherent mass. Stage II- Sticky Stage:Stage II- Sticky Stage: The monomer attacks theThe monomer attacks the polymer by penetrating into the polymer by penetratingpolymer by penetrating into the polymer by penetrating into the polymer. The mass is sticky and stringyinto the polymer. The mass is sticky and stringy (cobweb like) when touched or pulled apart.(cobweb like) when touched or pulled apart. Stage III- Dough or Gel Stage:Stage III- Dough or Gel Stage: As the monomer diffusesAs the monomer diffuses into the polymer, it becomes smooth & dough like. Itinto the polymer, it becomes smooth & dough like. It does not adhere to the walls of the jar. It consists ofdoes not adhere to the walls of the jar. It consists of undissolved polymer particles suspended in a plasticundissolved polymer particles suspended in a plastic matrix of monomer & dissolved polymer.matrix of monomer & dissolved polymer. www.indiandentalacademy.comwww.indiandentalacademy.com
  39. 39. Stage IV- Rubbery Stage:Stage IV- Rubbery Stage: The monomer disappears byThe monomer disappears by further penetration into the polymer &/or evaporation.further penetration into the polymer &/or evaporation. The mass is rubberlike, non plastic & cannot beThe mass is rubberlike, non plastic & cannot be moulded.moulded. Stage V- Stiff Stage:Stage V- Stiff Stage: Final stage in which the mass is stiff and hard.Final stage in which the mass is stiff and hard.  Working time - Time elapsing between stage II &Working time - Time elapsing between stage II & beginning of stage IVbeginning of stage IV  5 min5 min www.indiandentalacademy.comwww.indiandentalacademy.com
  40. 40. CHEMICALLY ACTIVATED DENTURECHEMICALLY ACTIVATED DENTURE BASE RESINSBASE RESINS CompositionComposition  liquidliquid  Methyl methacrylateMethyl methacrylate  Dimethyl-p-toluidineDimethyl-p-toluidine  Dibutyl phthalateDibutyl phthalate  Glycoldimethacrylate 1-2%Glycoldimethacrylate 1-2%  Hydroquinone 0.006%Hydroquinone 0.006% PowderPowder  Poly(methyl methacrylate)Poly(methyl methacrylate)  Benzoyl peroxideBenzoyl peroxide  Compounds of mercuric oxide, cadmium sulfideCompounds of mercuric oxide, cadmium sulfide  Zinc or titanium oxideZinc or titanium oxide  Dibytyl phthalateDibytyl phthalate  Glass fibers or beadsGlass fibers or beads www.indiandentalacademy.comwww.indiandentalacademy.com
  41. 41. Advantages & disadvantagesAdvantages & disadvantages  Better initial fit because of less thermalBetter initial fit because of less thermal contractioncontraction  Inferior color stability because of oxidation ofInferior color stability because of oxidation of tertiary aminetertiary amine  Inferior properties because of less degree ofInferior properties because of less degree of polymerizationpolymerization  Preferable for denture repairPreferable for denture repair  Greater chances of porosityGreater chances of porosity  Lower average molecular weightLower average molecular weight  Less strongLess strong www.indiandentalacademy.comwww.indiandentalacademy.com
  42. 42. ManipulationManipulation Sprinkle on techniqueSprinkle on technique Adapting techniqueAdapting technique Fluid resin techniqueFluid resin technique Compression moulding techniqueCompression moulding technique Injection moulding techniqueInjection moulding technique www.indiandentalacademy.comwww.indiandentalacademy.com
  43. 43. Light activated denture base resinsLight activated denture base resins  It consists of a urethane dimethacrylate matrix withIt consists of a urethane dimethacrylate matrix with an acrylic copolymer, microfine silica fillers, and aan acrylic copolymer, microfine silica fillers, and a camphoroquinone amine photo initiator systemcamphoroquinone amine photo initiator system  Supplied as premixed sheetsSupplied as premixed sheets  Cured in a curing unit with blur light of 400- 500 nmCured in a curing unit with blur light of 400- 500 nm from high intensity quartz halogen bulbsfrom high intensity quartz halogen bulbs www.indiandentalacademy.comwww.indiandentalacademy.com
  44. 44.  To examine the applicability of visible light-To examine the applicability of visible light- cured resins to orthodontics. In all physicalcured resins to orthodontics. In all physical property testing, it was found that VLC resinsproperty testing, it was found that VLC resins met or exceeded required values as establishedmet or exceeded required values as established by ADA Specification No. 12 for denture baseby ADA Specification No. 12 for denture base polymers.polymers.  In vitro bacterial adherence studies showed thatIn vitro bacterial adherence studies showed that more organisms adhered to heat-curedmore organisms adhered to heat-cured specimens than to the other specimens. In vivospecimens than to the other specimens. In vivo studies using split-palate Hawley retainersstudies using split-palate Hawley retainers demonstrated slightly less bacterial adherencedemonstrated slightly less bacterial adherence to BC than to the other resinsto BC than to the other resins www.indiandentalacademy.comwww.indiandentalacademy.com
  45. 45. Properties of denture resinsProperties of denture resins www.indiandentalacademy.comwww.indiandentalacademy.com
  46. 46. www.indiandentalacademy.comwww.indiandentalacademy.com
  47. 47.  Biocryl ICE is an ultra-clear, non-yellowing acrylic resin shown by CIE colorBiocryl ICE is an ultra-clear, non-yellowing acrylic resin shown by CIE color measurements to be the clearest acrylic available. Period. Biocryl ICE is ameasurements to be the clearest acrylic available. Period. Biocryl ICE is a fast setting, extremely workable material ideal for splints and a variety offast setting, extremely workable material ideal for splints and a variety of other appliances. The exceptional clarity of Biocryl ICE makes it the perfectother appliances. The exceptional clarity of Biocryl ICE makes it the perfect choice for esthetic-conscious patientschoice for esthetic-conscious patients www.indiandentalacademy.comwww.indiandentalacademy.com
  48. 48. www.indiandentalacademy.comwww.indiandentalacademy.com

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