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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: 01-12-2012

Copyright Statement:  Copyright © 2012; The Author(s).


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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  1. A clinical evaluation of posterior composite restorations: 17-year findings. J Dent 2006;34:427-35.
  2. Microhardness assessment of different commercial brands of resin composites with different degrees of translucence. Braz Oral Res 2008;22:358-63.
  3. Wear and marginal breakdown of composites with various degrees of cure. J Dent Res 1997;76:1508-16.
  4. A comparison of the wear resistance and hardness of indirect composite resins. J Prosthet Dent 2001;85:386-95.
  5. An energy-balance analysis for the size effect in low-load hardness testing. J Mater Sci 2000;35:209-13.
  6. New developments of polymeric dental composites. Progress in Polymer Science 2001;26:535-76.
  7. Composite resin microhardness: The influence of light curing method, composite shade, and depth of cure. J Contemp Dent Pract 2008;9:43-50.
  8. Effect of different light-curing devices and aging procedures on composite knoop microhardness. Braz Oral Res 2009;23:473-79.
  9. The Knoop hardness of a composite resin polymerized with different curing lights and different modes. J Contemp Dent Pract 2007;8:52-59.
  10. Correlation between hardness and degree of conversion during setting reaction of unfilled dental restorative resins. Dent Mater 1985;1:11-14.
  11. Flexural strength and hardness of direct and indirect composites. Braz Oral Res 2009;23:5-10.
  12. The relationship between composition and properties of posterior resin composites. J Dent Res 1990;69:852-56.
  13. Hardness and degree of conversion of posterior packable composites. Oper Dent 2004;29:642-49.
  14. Correlation between degree of conversion, microhardness and inorganic content in composites. Pesquisa Odontológica Brasileira 2002;16:349-54.
  15. Microstructural characterization and fracture behavior of a microhybrid and a nanofill composite. Dent Mater 2008;24:1281-88.
  16. Filler features and their effects on wear and degree of conversion of particulate dental resin composites. Biomaterials 2005;26:4932-37.
  17. Errors associated with depth-sensing microindentation tests. J Mater Res 1995;10:1491-501.
  18. Microhardness studies of chain-extended PE: II. Creep behaviour and temperature dependence. J Mater Sci 2000;35:1315-19.
  19. Comparative hardness and modulus of tooth-colored restoratives: A depth-sensing microindentation study. Biomaterials 2004;25:2179-85.
  20. Deconvolution of hardness from data obtained from nanoindentation of rough surfaces. J Mater Res 1999;14:2259-68.
  21. Effects of surface finish on indentation modulus and hardness of dental composite restoratives. Dent Mater 2005;21:1008-16.
  22. Effects of finishing/polishing time on surface characteristics of tooth-coloured restoratives. J Oral Rehabil 1998;25:456-61.
  23. Effects of finishing and polishing procedures on the surface texture of resin composites. Dent Mater 1994;10:325-30.
  24. Surface roughness of composite resins after finishing and polishing. Braz Dent J 2003;14:37-41.
  25. Surface hardness of light-cured and selfcured composite resins. J Prosthet Dent 1991;65:215-20.
  26. In vitro wear of composite with varied cure, filler level, and filler treatment. J Dent Res 1997;76:1405-11.
  27. Shear punch strength and flexural strength of model composites with varying filler volume fraction, particle size and silanation. Dent Mater 2003;19:206-11.
  28. Effects of various finishing systems on the surface roughness and staining susceptibility of packable composite resins. Dent Mater 2003;19:12-18.
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