A NEW COPOLYMERIZED COMPOSITE RESIN SYSTEM - A MULTIPHASED EVALUATION

Most microfilled composite resins are relatively resistant to generali zed wear; however, they commonly exhibit poor resistance to localized wear because of debonding of prepolymerized particles from the resin m atrix. A copolymerized new composite resin, in which the filler partic le trimethylol-propane-trimethacrylate is chemically bonded to the res in matrix is evaluated. Epic-TMPT was subjected to both generalized an d localized wear tests that revealed that its wear resistance was high er than that of other composite resin systems. Epic-TMPT in posterior occlusal cavities showed less than 8 mu m of wear for each restoration , 1 year after placement. Placement of Epic-TMPT into large anterior a bfraction lesions without mechanical retention, with surface etching, and subject to severe traumatic occlusion resulted in 87% retention 1 year after placement. In vivo usage biocompatibility tests demonstrate d no pulpal irritation or inflammation when Epic-TMPT was placed on vi tal dentin of crown preparations with complete enamel removal.