Hardness and Flexural Strength of Direct Restorative and Laboratory-Processed Composites

Objectives: The aim of this study was to evaluate the Knoop hardness and flexural strength of laboratory-processed resin composites and direct restorative composite submitted to different photo-curing methods. Methods: Twenty samples of Filtek Z250 (3M Espe) and Sinfony (3M Espe) were made, measuring 25 x 2 x 2mm and photo-cured in a vacuum-light chamber (Visio Beta Vario system, 3M Espe) and LED source (Elipar Freelight 2, 3M Espe). After 24 hours, the specimens were submitted to flexural strength test in an Emic universal test machine and the Knoop hardness was measured in a microhardness tester. Results: The results showed that Filtek Z250 showed high values of hardness and flexural strength than Sinfony (p<0.05). There was no difference between the photo-curing methods in the flexural strength but the Visio Beta Vario system showed high values of Knoop hardness than Elipar Freelight 2 (p<0.05). Conclusion: Mechanical properties as Knoop hardness and flexural strength can be influenced mainly by the resin-based composites composition compared with the photo-curing methods.