Evaluation of the Quality of Undergraduate Full Veneer Crown Preparations at a UK Dental Teaching Hospital

Objectives: To determine the quality of full veneer crown preparations produced by supervised undergraduate students at a UK dental teaching hospital. Methods: One hundred and eighty-five scanned digital dies between October 2019 and March 2021 were obtained. Using cross-sections in four planes, the total angle of convergence, abutment height, margin design and margin depth were evaluated. Statistical comparisons were made by plane, location, material-type, tooth-type, and inter- and intra-arch positions. Results: Across all preparations the mean total angle of convergence was 24.8° ± 11.7°. and mean abutment height was 3.6 mm ± 1.0 mm. Mandibular and molar teeth were significantly more tapered (P <0.001) and exhibited significantly shorter abutment heights (P <0.001). Chamfer margins were the most frequently observed and mean margin depths ranged from 0.49-1.06 mm. The compliance to recommended taught parameters were 28.1%, 42.7%, 34.1% and 6.5% for total angle of convergence, abutment height, margin design and margin depth, respectively. Conclusions: The findings from this study suggest that compliance to taught parameters is poor, especially for molar teeth, and demonstrates the use of digital software in guiding future research and teaching.

CAD/CAM Full Veneer Crowns Preparation Geometry Digital Evaluation