Assessment and evaluation of errors in tooth preparation by undergraduate students: an institution based in-vitro study

Abstract

Aim: To assess the errors made during preclinical tooth preparation by the undergraduate students of Meenakshi Ammal Dental College and Hospital, Chennai. Objectives: To understand the reason, nature and frequency of the errors occurring during tooth preparation done by undergraduate dental students during their preclinical practice. Materials and Methods: A total of hundred samples were collected from the undergraduate students. All the samples were upper right central incisors (11) typodont teeth, prepared to receive an All-ceramic crown. All the samples were prepared by mounting the typodont (NISSIN Typodont Jaw Model) on a phantom head simulator. All the preparations were made as freehand preparations. The following aspects of the preparation were evaluated: 1. Facial and palatal reduction 2. Occlusal clearance 3. Finish line width The evaluation of all the three aspects was done by studying a cross-section of an impression made on the prepared tooth. The impressions were made using a hard splint, which was fabricated on the typodont jaw model, prior to tooth preparation, as an impression tray. The impression material used was Light body(Zhermack Elite HD – Light normal set) impression material Results: The measurements and values obtained were subjected to statistical analysis to obtain the final result. Regarding the amount of prepared tooth surface, the frequency of errors encountered was more with regard to palatal reduction. Regarding the width of the finish line, Labial aspect of the finish line was most commonly under prepared. Conclusion: Within the limitations of the study, the main recommendation is to increase the pre-clinical practice time to emphasise more on the clinical expertise and the importance of proper operator positioning during tooth preparation. Key Words:Tooth preparation, All-ceramic restorations, Errors