A method of assessing the effectiveness of the friction fit interface by measuring reverse torque

• Published in: The Journal of prosthetic dentistry Vol. 112; no. 4; pp. 839 - 842
• Main Authors: Rodrigues Neto, Dimas João, DDS, MSc, Cerutti-Kopplin, Daiane, DDS, MSc, do Valle, Accácio Lins, DDS, PhD, Pereira, Jefferson Ricardo, DDS, MSc, PhD
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.10.2014
• Subjects: Dental Abutments; Dental Implant-Abutment Design; Dental Implants; Dental Marginal Adaptation; Dental Prosthesis Design; Dentistry; Friction; Humans; Humidity; Materials Testing; Stress, Mechanical; Surface Properties; Temperature; Time Factors; Torque
• ISSN: 0022-3913; 1097-6841
• DOI: 10.1016/j.prosdent.2014.02.013

Statement of the problem The connection between abutments and implants is fundamental to successful prosthetic rehabilitation, and the loosening or fracture of the parts are undesirable outcomes. Purpose The purpose of this study was to measure the reverse torque values of 2 different types of Morse taper implants. Material and methods Ten Morse taper implants were used, with their respective abutments. They were divided into 2 groups (n = 5): Group DH, implant interface with a double hexagon and Group OI, octagonal implant interface. Each abutment received 2 consecutive insertion torques (32 Ncm) at a 10-minute interval and 1 reverse torque after 5 minutes. The data were analyzed with the Student t test (α= .05). Results The Student t test demonstrated no significant differences between the values of the insertion and removal torques of the 2 groups (Group DH, P = .22 and Group OI, P = .42) or the removal torque values of the groups ( P = .12). Conclusion The results suggest that the strength required to loosen the abutment screws as measured by reverse torque is similar for both a double hexagon interface (DH) and an octagonal interface (OI).