Surface Roughness of Composite Resins Before and After Finishing

Abstract

The surface roughness before and after polishing with sand paper discs, cuttlefish discs, and aqueous suspensions of pumice was studied on 6 composite resins (Adaptic ®, Addent 12 ®, Blendant®, Dakor®, D.F.R.® and TD 71®) and two reference materials (Sevriton Simplified® and Biotrey®), with an apparatus, type Perth-O-Meter S4 BD Lowener, where mechanical registrations of the surface profiles were made. The sources of variance used were operators (2), strips (2), test pieces (2), materials (8) and surface treatments (4).

The results, as given by the CLA- and R^MAX-values of the studied surfaces, indicate that the brands of composite resins investigated differed in surface roughness both directly after setting and after the three different types of surface grinding used. The main finding, however, was that no type of grinding could produce as plane surfaces as that found after the resins had set under strips.

When the composite resins as a group were compared with a silicate cement they seemed to have smoother surfaces, especially when no grinding had been performed. When compared with polymethylmethacrylate they seemed to have about the same grade of surface roughness after setting. After grinding, however, most of the tested composite resins had rougher surfaces.

Key Words:

• Dental Materials
• Dental restorations
• permanent
• Resins
• Surface properties