Effect of Differences in Axial Thickness and Type of Cement on Fracture Resistance in Composite Resin CAD/CAM Crowns

Bull Tokyo Dent Coll. 2019 Feb 28;60(1):17-27. doi: 10.2209/tdcpublication.2018-0022. Epub 2019 Jan 31.

Abstract

The purpose of this study was to investigate the influence of differences in axial thickness and type of cement on fracture load in CAD/CAM crowns. Assuming the mandibular first premolar to be the abutment tooth, 4 types of crown with different axial thicknesses and radii of curvature were prepared. To unify external design, the morphology of the crown margins was set at 0.15, 0.30, 0.45, or 0.60 mm, thus maintaining uniform axial form of the crowns. The CAD/CAM crowns and abutment teeth were bonded using each of 2 types of resin cement or polycarboxylate cement. The fracture load value was measured using a universal testing machine and the destruction phase observed.No significant difference was observed with change in axial thickness. The fracture load values with each of the 2 types of resin cement used were significantly higher than that with polycarboxylate cement (p<0.01). These results suggest that the fracture load values of CAD/CAM crowns are not influenced by differences in the axial thickness of the crown, and that they are higher when bonding is achieved with resin rather than polycarboxylate cement.

MeSH terms

  • Composite Resins / therapeutic use*
  • Computer-Aided Design*
  • Crowns*
  • Dental Cements / therapeutic use*
  • Dental Prosthesis Design / methods*
  • Dental Restoration Failure
  • Dental Stress Analysis
  • Humans
  • Weight-Bearing

Substances

  • Composite Resins
  • Dental Cements