Impact of Heat on the Torque of Prosthetic Screws: An In vitro Study

Abstract

Aim: To evaluate whether applying heat to the implant surface can reduce the torque of the prosthetic screw. Study Design: Comparative in vitro experimental study. Place and Duration of Study: Department of Restorative Dentistry, School of Dentistry, Federal University of Minas Gerais between January 2023 and March 2025. Materials and Methods: In this in vitro study, a total of 40 implants were installed in bovine rib blocks, featuring Morse taper (MT) and external hexagon (EH) connections and they were divided into 4 groups: MT test (n =10), MT control (n=10), EH test (n=10) and EH control (n=10). Heat was applied at 47°C to the test groups prior to measuring the detorque of the prosthetic screws. The detorque value was also measured for the control groups. Data were analyzed using IBM SPSS Statistics (Version 26). Descriptive analysis, Shapiro-Wilk test for normality, and paired t-test were performed, with a significance level set at 5% (P=.05). Results: The results showed no significant differences in torque compared to the experimental group. Conclusion: The application of heat at 47ºC did not reduce the torque of prosthetic screws in dental implants. Although these results were obtained under controlled in vitro conditions, they suggest that exposure to 47°C — similar to temperatures during hot food ingestion — does not significantly affect prosthetic screw removal. Clinical studies are required to validate these findings and assess their practical implications.