A Comparative Evaluation of Wear of Enamel to Various Restorative Materials of Different Surface Finishes-An In Vitro Study

Aim:The aim of this study is to evaluate the effect of different surface finish of various restorative materials on the wear of opposing enamel.Objectives of the study:1.To compare the amount of enamel loss in experimental groups of various restorative materials at different intervals of masticatory cycles. 2.To compare and evaluate the most compatible finished or polished surface of the restorative material causing least enamel wear. Materials and Methods: A total of 90 samples were prepared for this study - 75 in disc form and 15 enamel antagonist and divided into 6 groups. Group 1 - Enamel vs Enamel antagonist, Group 2 - Enamel vs Fiber Reinforced Composite disc, Group 3 Enamel vs  Autoglazed metal ceramic disc , Group 4 - Enamel vs  Overglazed metal ceramic disc, Group 5 - Enamel vs Polished  metal ceramic  disc by polishing kit, and Group 6 - Enamel vs PEEK disc were fabricated. 105 extracted premolars were collected and randomly divided into six groups of 15 each and 15 for enamel antagonist. Each tooth sample was weighed before wear testing using electronic analytical balance of 0.0001 g accuracy. Occlusal surfaces of these teeth were then abraded against the substrates in a wear machine for a total of 10,000 cycles. Each tooth sample was weighed after 5000 cycles and after the total of 10,000 cycles, respectively, using the same balance. Differences in weight of tooth samples before and after wear testing were evaluated statistically using One-way analysis of variance and Tukey’s post hoc tests was used. Results:  The values obtained for overall mean percentage weight loss after 10000 rotations in increasing order is observed: Group 1 (Enamel Vs Enamel 0.0043 ± 0.00) < Group 6 (Enamel Vs PEEK disc 00.0131 ± 0.01) < Group 2 (Enamel Vs Fiber reinforced composite 0.0258 ± 0.01) < Group 5 (Enamel Vs Polished metal ceramic disc 0.0294 ± 0.00) < Group 3 (Enamel Vs Autoglazed metal ceramic disc 0.0318 ± 0.01) < Group 4 (Enamel Vs Overglazed ceramic disc 0.0451 ± 0.01). Conclusion:PEEK showed the least amount of enamel wear followed by Fiber reinforced composite. Fiber reinforced composite may cause less wear than dental ceramics. Enamel wear produced by polished metal ceramic disc  is substantially less than autoglazed and over glazed metal ceramic disc. This study indicates that any potential damage to ceramic can directly affect enamel and suggests that porcelain should be polished instead of over glazed. Key Words: Fiber reinforced composite, Autoglazed, Overglazed, Polished  surface, Wear, PEEK.