Laboratory evaluation of composite wear resistance with and without occlusal index

Laboratory evaluation of composite wear resistance with and without occlusal index Dr. MJ. Moghadas * - Dr. N. Sarabi * - Dr. H. Ameri * - Dr. A. Salehi** *Assistant Professor of Operative Dentistry Dept., Faculty of Dentistry, Mashhad University of Medical Sciences. ** Dentist. Abstract Background and Aim: The polishing and finishing procedures may cause topographical changes and introduce subsurface micro-cracks in dental composite restorations. The effect of Occlusal Index on the amount of wear in the posterior composite restorations was evaluated. Likewise, a comparison was made between the wear rates of Tetric Ceram and Ideal Makoo composite resin products. Materials and Methods: A total of 40 premolars were collected and randomly divided into four groups. Occlusal Indices were prepared with a transparent acrylic resin (Duralay). Class I cavities were prepared in all specimens. In two groups, teeth were restored with Occlusal Index. However, the restorations were completed without any Occlusal Index in the other two groups. Wear on the surfaces of these restorations were made by an oral cavity simulator and a tooth-brush machine. The vertical sections of the “pre-wear “and “post-wear “replicas were compared with a Projector Profilometer and the differences between the two sections were analyzed using two way ANOVA test at α=0.5. Results: The results showed that the mean-wear in index groups was higher. The findings did not show any significant difference between the wear rates of the two materials used in this experimental evaluation. Conclusion: The uses of occlusal index dose not decrease the wear of posterior composite restorations. Key words: Composite – Wear - Occlusal index Correspondence Author: Operative Dentistry Dept., Faculty of Dentistry, Mashhad University of Medical Sciences. e.mail:[email protected]