The Average of Skill in Fixed Prosthesis among Dental Students in the University of Palestine in 2018-2019
Al-Quds University, Deanship of Scientific Research
Prostheses are used to rehabilitate mastication, improve esthetics, and aid speech. Teeth require preparation to receive restorations. These preparations must be based on fundamental principles from which basic criteria can be developed to help predict the success of prosthodontic treatment. Among the fundamental principles of tooth preparation are the retention and resistance forms. Both can be achieved by providing a geometrical shape for the prepared tooth with minimal occlusal convergence angles (Hinnara S,2017). The convergence angle (CA) of a tooth preparation is the combined angle made by opposing axial walls when measured against the vertical long axis of the tooth. Textbooks in fixed prosthodontics often recommend an ideal convergence angle of approximately 5° (4–6°) and an acceptable range of 4–14° (Journal of Dental Education,2013). Dental students studying at the University of Palestine in previous years had difficulties in preparing teeth to achieve the generally recommended CA of less than 12°. This Experimental study aims to determine applicability of convergence angles among dental students in the University of Palestine in 4th and 5th year, and compare the reliability of the evaluation done by two investigators with that of AutoCAD. One hundred full crown casts will be selected randomly from preparations made by fourth and fifth year undergraduate students. Two images will be obtained from each of the 200 dies using a Canon 5D iii camera in which the die is placed B-L in one picture and M-D in the other. The pictures will then be scaled to the original scale. By means of AutoCAD 14, lines will be drawn parallel to either the traced axial walls in the gingival one third of the buccal and lingual surfaces or all proximal surfaces. These lines will then be extended until they meet to form an angle above the convergence angles in the images that will be measured using the software tools.