A Cavity Preparation Evaluation System in the Skill Assessment of Dental Students

The aim of this study was to compare a computerized, laser-scanning Cavity Preparation Skill Evaluation System (CPSES) with conventional teachers' eye-hand grading assessment of dental students' Class I cavity preparation evaluations. Thirty-eight cavity preparations of lower left first molars made by junior dental students at a dental school in China were tested from September 2013 to November 2014. The outline and retention form, smoothness, depth, wall angulation, and cavity margin index of the preparations were evaluated by CPSES and then by teachers' eye-hand grading. The mean difference in scores for each method was considered, as was the variability of scores within each method. Compared with the teachers' eye-hand grading method, CPSES provided objective evaluation results that had statistically significant differences (p<0.05). A questionnaire was also designed and distributed to the students; the response rate was 100%. The results indicated that most of the students recognized CPSES effects in the preclinical teaching; 92.1% perceived that CPSES provided high simulation and appropriate practice guidance for them; and 94.7% reported that the evaluation results provided by CPSES gave targeted and objective recommendations. These findings suggest that CPSES can consistently and reliably scan a student's tooth preparation, compare it to a theoretically ideal preparation, and provide objective feedback. The application of CPSES in preclinical operative training can help students better understand the desired parameters for occlusal cavity preparation skills and encourage students in their self-paced learning and independent practice.