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VOLUME 13 , ISSUE 3 ( May-June, 2012 ) > List of Articles

ORIGINAL RESEARCH

Correlation between Surface Roughness and Microhardness of Experimental Composites with Varying Filler Concentration

Eliseu Aldrighi Münchow, Marcos Brito Correa, Fabrício Aulo Ogliari, Evandro Piva, Cesar Henrique Zanchi

Citation Information : Münchow EA, Correa MB, Ogliari FA, Piva E, Zanchi CH. Correlation between Surface Roughness and Microhardness of Experimental Composites with Varying Filler Concentration. J Contemp Dent Pract 2012; 13 (3):299-304.

DOI: 10.5005/jp-journals-10024-1141

Published Online: 01-06-2012

Copyright Statement:  Copyright © 2012; Jaypee Brothers Medical Publishers (P) Ltd.


Abstract

Aim

The purpose of this study was to investigate the influence of the surface roughness on the surface microhardness of experimental composites with varying filler concentration.

Materials and methods

Experimental resin composites were formulated by mixing Bis-GMA and TEGDMA in a 50/50% weight ratio and CQ/EDAB were added to make the material photosensitive. Silanized glass particles were incorporated in the resin blend in two concentrations: C50 with 50% and C75 with 75% in weight ratio. The surface roughness and the surface microhardness measurements were determined after every three finishing procedures with #280-, #600- and #1200-grit wet sandpapers, respectively. The data were analyzed statistically by Two Way ANOVA and Tukey's test, and comparisons were conducted using the Spearman's correlation test (p < 0.05).

Results

The surface roughness and surface microhardness were negatively associated (r = – 0.68) and the finishing procedures of both composites resulted in harder and smoother surfaces than the initial ones. Additionally, in a smooth circumstance, the higher content of fillers has not resulted in a composite with better microhardness and smoothness.

Conclusion

Finishing procedures decreased the surface roughness and consequently improved the surface microhardness of the composites evaluated.

Clinical significance

Finishing and polishing procedures are effectives in reducing the surface roughness amplitude of composite materials and in improving their surface microhardness. Thus a microhardness test and any hardness evaluation must be conducted only after a properly finished and polished surface is achieved.

How to cite this article

Münchow EA, Correa MB, Ogliari FA, Piva E, Zanchi CH. Correlation between Surface Roughness and Microhardness of Experimental Composites with Varying Filler Concentration. J Contemp Dent Pract 2012;13(3):299-304.


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