Heat Effect on Viscosity and Curing of Light-Cured Dental Resin and Mechanical Strength of Conventional Dental Composites
Keywords:
Dental Material, Dental Composites, Silanized Silica, HardnessAbstract
Dimethacrylate polymers and silica are most commonly used as matrix resins and fillers for dental composites. Bis-GMA, UDMA are used as base monomers and TEGDMA as a diluent monomer for dental resin preparation. Pure UDMA, mixtures of UDMA:TEGDMA and Bis-GMA:TEGDMA 50:50 and 75:25 were mixed with silanized silica at compositions of monomer:fillers 30:70 and 40:60 (weight ratio). Heat curing of the monomers was studied by DSC and showed that temperature did not have an affect on curing from room temperature to 80°C. The viscosity of the monomers decreased as temperature increased; i.e. by the change of 50°C viscosity reduced to 3-5% of original values at 30°C. There was no significant difference in diametral tensile strength (DTS) of the dental composites having a monomer mixture of 50:50 and 75:25. Stiff monomer (Bis-GMA) shows a higher DTS and Vicker hardness than the flexible one. However, filler content is more prominent in controlling DTS and Vicker hardness than monomer type and ratio. The prepared dental composites showed lower DTS and hardness than the commercial ones.
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Arcis, R. W., Lopez-Macipe, A., Toledano, M., Osorio, E., Rodriguez-clemete, R., Fanovich, M.A. and Pascual, C.D. 2002. Mechanical properties of visible light-cured resins reinforce with hydroxyapatite for dental restorative. Dent. Mater. 18 : 49- 57.
Asmussen, E. and Peutzfeldt, A. 1998. Influence of UEDMA, BisGMA and TEGDMA on selected mechanical properties of experimental resin composites. Dent. Mater 14(1) : 51-56.
Bowen, R. L. 1962. Dental filling material comprising vinyl silane treated fused silica and a binder consisting of a reaction product of bisphenol and glycidyl Acrylate. U.S.Patent, 3,006,112. Novemeber.
Chowdhury, N. A., Wakasa, K., Priyawan, R. and Yamaki, M. 1995. Effect of filler content on mechanical strength in bis-GMA base resins with urethane linkages. J. Mater. Sci. 6 : 400-403.
Council on Dental Materials and Device. 1997. New American Dental Association Specification No. 27 for direct filling resins. J. Am. Dent. Assoc. 94 : 1191-1194.
Htang, A., Ohasawa, M. and Matsumoto, H. 1995. Fatique resistance of composite restorations: effect of filler content. Dent. Mater. 18 : 7-13.
Imazato, S., McCabe, J. F., Tarumi, H., Ehara, A. and Ebisu, S. 2001. Degree of conversion of composites measured by DTA and FTIR. Dent. Mater. 17 : 178-183.
Johnson, W. W., Dhuru, V. B. and Brantley, W. A. 1993. Composite microfiller content and its effect on fracture toughness and diametral tensile strength. Dent. Mater. 9 : 95-98.
Johnston, A. D., Dickens-Venz, S. H., Takagi, S., Chow, L. C., Bowen, R. L. and Dicken, B. 1994. Physical and chemical properties of resin-reinforced calcium phosphate cements. Dent. Mater. 10 : 100-106.
Leinfelder, K. F. 1989. Composite resins : properties and clinical performance, In : O’Brien, W.J., (ed.). Dental Material: Properties and Selection. Chicago, Quintessence Publishing.
Leinfelder, K. F. 1991. Using composite resin as posterior restoration material. J. Am. Dent. Assoc. 122 : 65.
Lim, B. S., Feranceane, J. L., Condon, J. R. and Adey, J. D. 2002. Effect of filler fraction and filler surface treatment on wear of microfilled composites. Dent. Mater. 18 : 1-11.
Lovell, L. G., Newman, S. M. and Bowman, C. N. 1999a. The effect of light intensity, temperature, and comonomer composition on the polymerization behavior of dimethacrylate dental resins. J. Dent. Rest. 78(8) : 1469-1476.
Lovell, L. G., Stanbury, J. W., Syrpes, D. C. and Bowman, C. N. 1999b. Effect of composition and reactivity on the reaction kinetics of dimethacrylate/dimethacrylate coipolymerizations. Macromolecules. 32 : 3913-3921.
Lutz, F. and Phillips, R. W. 1983. A classification and evaluation of composite resin system. J. Prosthet. Dent. 50 : 480.
McCabe, J. F. 1985. Cure performance of light-activated composites by differential thermal analysis (DTA). Dent. Mater. 1 : 231-234.
Maiti, S. N. and Jeyakumar, R. 1990. Mechanical and melt rheological properties of CaCO3-filled polyethylene. J. Polym. Mater. 7 : 29-34.
Phillips, R. W. and Moore, B. K. 1994. Elements of Dental Materials for Dental Hygienists and Dental Assistants. Philadelphia, W.B. Saunders.
Roulet, J. F. 1987. Degradation of Dental Polymers. New York, Karger.Shajii, L. and Santerre, J. P. 1999. Effect of filler content on the profile of released biodegradation products in micro-filled bis-GMA/TEGDMA dental composite resins. Biomaterials. 20 : 1897-1908.
Shernoy, A. V. 1999. Rheology of Filled Polymer Systems. Dordrecht, Kluwer Academic Publishers.
Silikas, N. and Watts, D. C. 1999. Rheology of urethane dimethacrylate and diluent formulations. Dent Mater. 15 : 257-261.
Stansbury, J. W. and Dickens, H. S. 2001a. Network formation and compositional drift during photo-initiated copolymerization of dimethacrylate monomers. Polymer. 42 : 6363-6369.
Stanbury, J. W. and Dickens, H. S. 2001b. Determination of double bond conversion in dental resins by near infrared spectroscopy. Dent Mater. 17 : 71-79.
Vaidyanathan, J., Vaisyanathan, T. K., Wang, Y. and Viswanadhan, T. 1992. Thermoanalytical characterization of visible light cure dental composites. J. Rehabil. 19 : 49-64.
Zhao, D., Botsis, J. and Drummond, J. L. 1997. Fracture studies of selected dental restorative composites. Dent Mater. 13 : 198-207.
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