A Comparative Study of Potential Undercut Points Between Laboratory and Clinical Preparations

Abstract

Introduction and Objective: The ability of dentists to prepare teeth is essential for the success of the prosthetics applied to them. This depends on how doctors are prepared in dental colleges. Tooth preparation must have specific geometric properties to avoid creating undercuts areas that negatively affect the stability and fit of the prosthesis to the prepared teeth.

Research objective: This research aims to compare the undercuts areas when preparing abutments to receive metal-ceramic crowns by dental students in the laboratory and clinically, using digital scanning measurements, and to test the practical learning outcomes reflected in the performance of dental students at the Al-Wataniya Private University.

Materials and methods: The research sample consisted of 60 abutments prepared by fifth-year students to receive metal-ceramic crowns, 30 teeth prepared clinically by students under the conditions of the patients' oral cavity, and 30 acrylic teeth identical in shape, size, and position to the abutments of the first group before preparation and prepared by the same students in the laboratory. The measurements were performed digitally by CAD\ CAM using Exocad software.

Results: A chi-square test was performed to compare the frequency of the number of surfaces containing fixation points between the two groups. The chi-square value in the clinical group was 5.83, while in the laboratory group it was 4.66, with no statistically significant differences between the two groups.

Conclusions: The frequency of undercut points in laboratory preparation was higher than in clinical preparation, with no statistically significant differences.