Rugosidade superficial de resina composta submetida a diferentes tratamentos de superfície - estudo in vitro / Superficial roughness of composite resin submitted to different surface treatments - an in vitro study

ABSTRACT

The objective was to evaluate the superficial roughness of a composite resin submitted to different surface treatments, in vitro. Thirty specimens were made with P60TM packable composite resin (3M ESPE), 6 mm thick and 3 mm in diameter. The samples were stored in distilled water for 7 days at 37 ºC and randomly assigned to two test groups. The baseline superficial roughness was determined with a profilometer. Fifteen specimens of each material were subjected to the following finishing and polishing procedures Group I multi-fluted burs/aluminum oxide disks (Diamond ProTM, FGM); Group II multi-fluted burs/rubber tips (Enhance/PogoTM, Dent-sply). Time was limited to 20s per instrument. Following these procedures, it was accomplished a new reading and storage. Then the samples were polished with felt disks with diamond paste (Diamond ExcelTM, FGM), for 20s, and a surface sealant was applied (Biscover, BIS-CO). After all these procedures, the final roughness was determined. Statistical analysis was performed with RM ANOVA and Tukey´s tests (5%). Significant effects were found with both the polishing systems and the sealant (presence or absence). The polishing with Diamond Pro caused the greatest roughness on all composites (p < 0.05). After the application of Biscover the composite surfaces were smoother. This difference was significant for the group polished with Diamond Pro and not sig-nificant for the group polished with EnhanceTM/Pogo. It was concluded that the application of a surface sealant following polishing with aluminum oxide disks or abrasive rubbers results in a surface with smoothness superior to that obtained with these polishing devices alone.