The effect of different finishing and polishing systems on surface roughness of new low polymerized composite materials : an in vitro study

الملخص EN

Background: Adequate finishing and polishing of resin composites is a prerequisite for high-quality esthetics and enhanced longevity of resin-based restorations.

Finishing and polishing of resin composites are important procedures in restorative dentistry.

Finishing refers to gross contouring of a restoration to obtain the desired contour.

However, polishing refers to smoothness as well as to reduction of the scratches created by the finishing instruments.

Materials and methods: Four types of composite materials where used in this study, FiltekP90 (3M ESPE, St.paul, U.S.A), Tetric Evoceram (Vivadent, Schaan, Liechtenstein), FiltekZ250 (3M ESPE, St.paul, U.S.A), FiltekP60 (3M ESPE, St.paul, U.S.A), also two polishing systems which are: Optrapol (Ivoclar Vivadent) and Enhance (Dentsply) and one Silicone carbide finishing paper.

A total number of 160 disc shaped specimens were produced in a circular steel molds with a circular hole in its center , with a diameter of (10×3mm), specimens where divided into four groups of 40 specimens each (10 samples from each composite type) according to the finishing/ polishing protocol used as follows Group A: control without finishing and polishing.

Group B: polishing using optrapol polishing system.

Group C: polishing with Enhance polishing system.

Group D: finishing only with silicone carbide finishing paper(600 grit).

Except for the control group Specimens first are finished using silicone carbide paper 600 grit for obtaining a baseline surface roughness before the application of polishing systems, the At the completion of the finishing and polishing instrumentation, the specimens were ultrasonically cleaned in an ultrasonic unit with distilled water for two minute.

The surface roughness was measured by using a portable surface roughness tester (SRT 6210).

Results: The result showed that all the composite materials under control group that cured using mylar strip exhibited the least surface roughness values (best smoothness).

All the composite materials produced smoother surface when polished with optrapol system than with Enhance system.

For the silicone carbide finishing paper we found that all the materials produced high surface roughness values than with other finishing and polishing systems and there was no significant difference between the composite materials.

Conclusion: FiltekP90 exhibited the smoothest surface finish compared to the other composite materials used in this study while FiltekP60 exhibited the roughest surface finish compared to the other composite materials used in this study.