Evaluation of the mechanical properties of light-cure composite resins submitted to post-cure

Abstract

Objective: This study evaluated the flexural strength and Vickers hardness of a direct restorative composite resin (Filtek P-60TM), submitted or not to the post-cure, and a laboratory composite resin (ArtglassTM). Methods: The flexural strength tests followed the ISO 4049:1988 regulations, and the Vickers microhardness tests the ASTM E-384:1999 regulations. The Filtek P-60TM com- posite resin was cure activated as follows: Group I - conventional light cure; Group II - conventional li- ght cure followed by post-cure with dry heat; Group III - conventional light cure followed by post-cure in a stroboscopic light unit; Group IV - ArtglassTM composite resin was light cured in a stroboscopic unit. After cure activation procedures, the samples were kept in deioni- zed water at 37 ± 1 oC for 24h and protected from light. Results were submitted to Anova and Duncan’s test and revealed an increase in flexural strength and Vickers microhardness test after Filtek P-60TM post-cure. Results and Conclusion: It is possible to conclude that the Vi- ckers microhardness values for Filtek P-60TM samples were superior to the ArtglassTM composite resin values; and that the flexural resistance values for Filtek P-60TM submitted to post-cure were superior to the ArtglassTM resin values.