Influence of abutment height and convergence angle on the retrievability of cement-retained implant prostheses with a lingual slot
10.4047/jap.2018.10.5.381
- Author:
Kyu Hyung CHOI
1
;
KeunBaDa SON
;
Du Hyeong LEE
;
Kyu Bok LEE
Author Information
1. Department of Prosthodontics, School of Dentistry, Kyungpook National University, Daegu, Republic of Korea. kblee@knu.ac.kr
- Publication Type:Original Article
- Keywords:
Lingual slot;
Cement-retained implant prostheses;
Abutment;
Computer-aided design and computer-aided manufacturing (CAD/CAM);
Retrievability
- MeSH:
Crowns;
In Vitro Techniques;
Peri-Implantitis;
Prostheses and Implants;
Resin Cements;
Shoulder;
Titanium;
Torque;
Water
- From:The Journal of Advanced Prosthodontics
2018;10(5):381-387
- CountryRepublic of Korea
- Language:English
-
Abstract:
PURPOSE: Cement-retained implant prostheses can lack proper retrievability during repair, and residual cement can cause peri-implantitis. The purpose of this in vitro study was to evaluate the influence of abutment height and convergence angle on the retrievability of cement-retained implant prostheses with lingual slots, known as retrievable cement-type slots (RCS). MATERIALS AND METHODS: We fabricated six types of titanium abutments (10 of each type) with two different heights (4 mm and 6 mm), three different convergence angles (8°, 10°, and 12°), a sloped shoulder margin (0.6 mm depth), a rectangular shape (6 mm × 6.5 mm) with rounded edges, and a rectangular ledge (2 mm × 1 mm) for the RCS. One monolithic zirconia crown was fabricated for each abutment using a dental computer-aided design/computer-aided manufacturing system. The abutments and crowns were permanently cemented together with dual-curing resin cement, followed by 24 hours in demineralized water at room temperature. Using a custom-made device with a slot driver and torque gauge, we recorded the torque (N·cm) required to remove the crowns. Statistical analysis was conducted using multiple regression analysis and Mann-Whitney U tests (α=.05). RESULTS: Removal torques significantly decreased as convergence angles increased. Multiple regression analysis showed no significant interaction between the abutment height and the convergence angle (Durbin-Watson ratio: 2.186). CONCLUSION: Within the limitations of this in vitro study, we suggest that the retrievability of cement-retained implant prostheses with RCS can be maintained by adjusting the abutment height and convergence angle, even when they are permanently cemented together.
