Assessment of angular deviations of the vertical surfaces of teeth stumps obtained during odontopreparation for fixed orthopedic structures (metal-ceramic and solid crowns)

Relevance. Odontoreparation is fundamental to ensure the functional efficiency, high aesthetics and durability of fixed prostheses. At present, with fixed prosthetics of defects in hard tissues of teeth and dentition, various types of artificial crowns are widely used [1, 2]. Purpose of the study: to determine the angular deviations of the vertical surfaces of molars, prepared by students of the 3rd year. Based on the data obtained, calculate the average value for the group and identify which surfaces of the stump are most prone to errors during odontopreparation. Materials and methods. Frasaco® phantom teeth (mandibular molars) were used as research materials. Preparation for metal-ceramic crowns was carried out according to the traditional method by thirteen third-year students of the Samara State Medical University of the Ministry of Health of Russia. In this work, 6° was taken as the optimal angle of convergence of the vertical walls (3° on each of the two opposite surfaces). During the preparation, a fissure bur d = 1.6 mm was used. Conclusion. The average time spent on preparation is quite long, which indicates an insufficient level of manual skills. The revealed phenomena of wall divergence also indicate that the preparation skills are insufficient. In addition, divergence was found mainly on the distal surface, which is explained by more difficult access and limited visibility of the prepared surface.