الفهرس | Only 14 pages are availabe for public view |
Abstract Purpose: This study evaluated the effect of microwave post-polymerization treatment of bulk- fill resin composite used as indirect restoration regarding; degree of conversion, compressive strength, micohardness and fracture toughness.Materials and Methods: Two nanohybrid resin composites were used in the study; one is incrementally-placed and the other is bulk-fill. For each test, ten specimens of each resin composite type were prepared according to manufacturer’s instructions (group I and II) and divided into two equal subgroups; one (Ia and IIa) as a control and the other subgroup (Ib and IIb) exposed to microwave post-polymerization treatment at 550 W for 4 min. Degree of conversion, compressive strength, microhardness and fracture toughness of different groups were calculated. Data were analyzed and compared using t-tests (P <0.05).Results: Bulk-fill resin composite showed a significant increase in compressive strength and fracture toughness mean values than those of the incrementally-placed one. In addition, there was a significant difference between the degree of conversion, compressive strength, microhardness and fracture toughness means of microwave-treated groups of both incrementally-placed and bulk-fill resin composites, and the control groups. Conclusion: Microwave post-polymerization treatment is an effective method to enhance the degree of conversion, compressive strength, microhardness and fracture toughness of nanohybrid resin composites, either bulk-fill or incrementally-placed when used as indirect restoration. |