International Journal of Dentistry Research 2024; 9(1): 15-18 ;   DOI:10.31254/dentistry.2024.9105

Research Article

Evaluation of Resistance and Retention form of Molar Crown Preparation for Porcelain Fused to Metal Crown at the University of Ghana Dental School

Stephen Ekow Ankoh¹ , Patrick Caldicock Ampofo¹ , Sandra Ama Hewlett¹ , Ebenezer Anno Nyako¹ , Tom AKuetteh Ndanu² , Akua Boakyewaa Konadu¹ , Ruby Yayra Goka¹ , Nana Frimpomaa Adu-Ampomah^1,3 , Gladia Toledo Mayari Yabang⁴ , Neil Quartey Papafio⁵

Stephen Ekow Ankoh,Patrick Caldicock Ampofo,Sandra Ama Hewlett,Ebenezer Anno Nyako,Tom AKuetteh Ndanu,Akua Boakyewaa Konadu,Ruby Yayra Goka,Nana Frimpomaa Adu-Ampomah,Gladia Toledo Mayari Yabang,Neil Quartey Papafio

1. Department of Restorative Dentistry, University of Ghana Dental School, Accra, Ghana
2. Department of Community Dentistry, University of Ghana Dental School, Accra, Ghana
3. Dental department, Adabraka Polyclinic, Accra, Ghana
4. Department of Orthodontics and Paedodontics, University of Ghana Dental School, Accra, Ghana
5. Department of Dental Biomaterial Sciences, University of Ghana Dental School, Accra, Ghana

*Author to whom correspondence should be addressed.

Received: 25th January, 2024 / Accepted: 25th March, 2024 / Published : 30th April, 2024

Abstract

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Background: It is recommended that for a molar crown preparation to have adequate resistance and retention form for a porcelain fused to metal (PFM) crown, it should have a clinically acceptable taper between 6-140 and a total occlusal convergence (TOC) also in the range of 6-220 . Aim: To determine whether the molar crown preparations for full-coverage PFM crowns made by Resident dentists at the University of Ghana Dental School (UGDS) meet the clinical requirement for resistance and retention form. Methods: This was a prospective study to analyse the taper and TOC which are some of the intrinsic factors of resistance and retention form. Seventy-seven molar crown preparations made by Resident dentists at UGDS were used. The Exocad software was used to measure the taper and TOC of each molar die. A descriptive summary of the taper and TOC were summarised as means and their standard deviations. Chi-square test was used to compare the acceptability levels of the variables with their respective recommended clinically acceptable values. Results: The mean buccal, lingual, mesial and distal taper recorded were 25.20 ± 15.30, 26.50 ± 14.30, 26.00 ± 12.50 and 26.90 ± 14.50 respectively. Also, the mesiobuccal, mesiolingual, distobuccal and distolingual taper recorded were 27.30 ± 7.70 , 27.30 ± 7.70, 26.10 ± 8.90, and 26.20 ± 7.40. The mean buccolingual TOC, mesiodistal TOC, Mesiobuccal-distolingual TOC and mesiolingual-distobuccal TOC recorded were 51.20 ± 26.90, 52.80 ± 24.10, 53.50 ± 12.90, and 52.30 ± 12.40. Conclusion: The current study showed that it was a challenge to achieve the recommended clinically acceptable values of taper and TOC to achieve adequate resistance and retention form.

Keywords

Resistance form, retention form, molar tooth, porcelain fused to metal crown, crown preparation

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