Fracture strength and behavior of resin-faced CAD/CAM anterior crowns

Abstract

The fracture strength and behavior of a novel resin-faced computer-aided design/computer-aided manufacturing (CAD/CAM) crown were investigated to evaluate application to the anterior teeth. Resin-faced CAD/CAM crowns were fabricated by arranging a resin composite on a frame prepared from a CAD/CAM resin block. The fracture strength was evaluated after 24 h of complete polymerization (day 0) and after water immersion for 30 days (day 30). Uniaxial loading was applied to the center point between the incisal edge and cingulum (loading point 1) or at 1.5 mm from the incisal edge (loading point 2). There was no significant difference in the fracture strength of the resin-faced CAD/CAM crowns between day 0 and 30 at loading point 1. At loading point 2, they exhibited decreased fracture strength after water immersion; however, the mean strength was still >1 kN. This novel crown showed good mechanical properties to serve as a prosthesis for the anterior teeth.