Evaluation of surface roughness of composite according to surface treatment

Abstract

The purpose of this study was to evaluate the effect ofvarious finishing and polishing procedures on the surface roughness(Ra) of two composite resins: An organically modifiedceramic (Definite) and a micro hybrid (Tetric).Thirty specimens of each composite resin were fabricatedusing a stainless steel mold of 5 mm in diameter and 2 mmin depth. The composite resin was covered by a Mylar stripand pressed flat with a microscopic glass slide and light cured.The specimens for each composite resin were divided intothree groups, each of ten. The specimens in group one receivedno treatment, while the specimens in group two and threewere finished with diamond bur. After finishing with diamondburs group three were polished with Sof–Lex discs.The surface profile of the specimens was obtained with asurface profile–testing machine (Profilometer). The roughnessvalue in micrometer (μm) was recorded as the average Ra.Results showed higher surface roughness in groups finishedwith diamond burs followed by groups finished with diamondburs and polished with Sof–Lex discs while groups setagainst Mylar strip showed the lowest roughness values. Theresult revealed no significant difference in surface roughnessvalues between the two composite resins.