Research Article
Volume 19 Issue 11 - 2020
Occlusal Convergence Angles of Teeth Preparation Achieved by Pre-Clinical Dental Students at Umm-Alqura University, Saudi Arabia
Abdulmajeed A Alluqmani1*, Ahmed S Alqurashi2, Majdi A Alhothali2, Anas A Alsaedi2 and Mohamed F Elmoafy3,4
1General Practitioner Dentist, Ministry of Health, Madina, Kingdom of Saudi Arabia
2General Practitioner Dentist, Ministry of Health, Makkah, Kingdom of Saudi Arabia
3Assistant Professor of Fixed Prosthodontics, Faculty of Dentistry, Umm Al-Qura University, Makkah, Saudi Arabia
4Assistant Professor of Fixed Prosthodontics Department, Faculty of Dentistry, Cairo University, Egypt
*Corresponding Author: Abdulmajeed A Alluqmani, General Practitioner Dentist, Ministry of Health, Madina, Kingdom of Saudi Arabia.
Received: September 19, 2020; Published: October 27, 2020


Aim: This study aims to determine the mean of convergence angles of each tooth in both aspects MD and BL which is produced by fourth-year dental students at Umm-Alqura University. Then compare it with ideal convergence angles and see which tooth prepared need to improve.

Materials and Methods: A total of 150 prepared teeth: 50 molars prepared to receive full metal crowns, 50 premolars prepared to receive porcelain fused to metal (PFM) crowns, 50 anteriors prepared to receive all-ceramic crowns. All samples were prepared in phantom labs. Images were captured with a digital camera. Mesio-distal (MD) and bucco-lingual (BL) tapers for each prepared tooth was measured by computer program.

Results: The mean BL angle of all preparations was 16.93 ± 6.43 degrees, while the mean MD angle was 15.65 ± 6.26 degrees. The mean BL angle for the molar tooth preparation (20.11 ± 7.65 degree) and the mean BL angle for the premolar tooth preparation (19.19 ± 4.21 degree) was significantly greater than the mean BL angle for the anteriors teeth preparations (11.50 ± 1.95 degree) (p = 0.000). On the other hand, no statistical difference was observed between the mean BL angle for the molar and premolar tooth preparation (p = 0.457). The mean MD angle for the molar tooth preparation (19.91 ± 7.72 degree) was significantly greater than the mean MD angle for the premolar tooth preparation (16.09 ± 3.98 degree) (p = 0.002). And the mean MD angle for the anteriors teeth preparations (10.96 ± 1.63 degree) (p = 0.000). The mean MD angle for the premolar tooth preparation was significantly greater than the mean MD angle for the anteriors teeth preparation (p = 0.000).

Conclusion: Most of BL and MD total occlusal convergence angles fall within an acceptable range, with low values being undercuts and excessive angles of up to 41.31 degree seen. This means the course did very well, but we need to increase the time of training and make sure the student work with the index to know the ideal amount of reduction.

Keywords: Artificial Teeth; Crown Preparation; Dental Students; Fixed Prosthodontics; Occlusal Convergence Angles; Pre-Clinical Education; Saudi Arabia; Taper


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Citation: Abdulmajeed A Alluqmani., et al. “Occlusal Convergence Angles of Teeth Preparation Achieved by Pre-Clinical Dental Students at Umm-Alqura University, Saudi Arabia”.EC Dental Science 19.11 (2020): 59-67.

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