THE EFFECT OF FINISHING AND POLISHING PROCEDURES ON THE SURFACE ROUGHNESS OF COMPOSITE RESIN MATERIALS: AN IN-VITRO STUDY

The present study was conducted to evaluate the effectiveness of various finishing and polishing procedures on the surface roughness of two different composite resin materials (nanofilled composite, microhybrid composite) and to evaluate the effect of the surface sealant application(prime and bond) on the surface roughness after finishing and polishing procedures of tested composites. A total of 60 composite discs of dimension 6 x 3 mm (6mm in diameter x 3mm in thickness) were made using a custom made stainless steel mould. Out of these sixty specimen, thirty were of nanofilled composite (Z-350 3M ESPE) and thirty were of microhybrid composite (Z-250 3M ESPE). These two groups were then again randomly divided into three subgroups for finishing and polishing by three different methods; SofLex, Shofu and Mylar strip). The average surface roughness (Ra, mu m) of all the specimen were measured with the profilometer. A surface sealant was then applied to all the treated specimens, according to manufacturer's instructions and the average roughness was measured again. Results were statistically analyzed using analysis of variance (ANOVA F) and the paired and unpaired 't' tests. The results showed that irrespective of the finishing and polishing systems used nanofilled composite exhibited a smoother surface than microhybrid composite. As for the effectiveness of finishing and polishing systems on both the composites, the Mylar strips gave lowest Ra values followed by Sof-Lex followed by Shofu and the surface sealant improved the surface texture of tested specimens drastically.