A comparative study between the angle of convergence of the anterior teeth and posterior teeth prepared to receive ceramic metal crowns by the students of the Syrian Private University in the pre-clinical stage

Abstract

Introduction and aim: good teeth preparation is considered one of the important factors for retention regarding fixed prosthodontics including abutment length, angle of convergence, etc…

The angle of convergence plays an important role in the success of prosthodontic procedures. The aim of our study was to compare the angle of convergence of the anterior teeth with the angle of convergence of the posterior teeth those prepared to receive metal ceramic crowns at the end of the pre-clinical stage by the students of the Faculty of Dentistry at the Syrian Private University and compare the results of this study with studies conducted in other universities.

Materials and Methods: The study consisted of 120 teeth prepared to receive a metal ceramic crown evenly distributed in centrals and canines (30 teeth in each group), and premolars and molars (30 teeth in each group). Each sample was placed in front of the camera so that the lens was vertical on the model and at a distance of 10 cm for each sample so that the corresponding mesio-distal and bucco-lingual walls were shown. These images were then transferred to the computer where the angle of convergence of the front and posterior teeth were determined by AutoCAD program.

Results: The mean angle of convergence of the front and back teeth was 17.11 and 21.61, respectively. The mean angle of the mesio-distal angular convergence of the front and back teeth was 19.56 and 23.46 degrees, respectively. It also showed that the bucco-lingual angular convergence angle of the front and back teeth was 14.62 and 19.76 degrees, respectively. The statistical T-test showed statistically significant differences in the average values ​​of the angle of convergence of the axial walls toward the grinding surface between the anterior teeth and the posterior teeth group.

Conclusion: At the end of the laboratory stage, students were able to provide preparations so that the angle of convergence of the anterior teeth was close to the ideal grade and with statistically significant differences from the angle of convergence of the posterior teeth.