Influence of Torque Type and Bone Loss on the Stability Quotient of Two Implants with Prostheses.

Abstract

Osseointegration is related to the stability of the screw and influences the success rate of implant-supported prosthetic rehabilitation, as it promotes natural healing and effective bone formation, facilitating the preservation of the implant in the recipient site. Factors such as surgical technique, insertion torque, the type of recipient bone, and the macro- and microstructure of the implant can affect screw stability. The objective of this study is to analyze in vivo the influence of insertion torque, recipient bone type, and peri-implant bone loss on the implant stability quotient (ISQ) values of cylindrical implants with external hexagon (EH) and Morse taper (MT) connections, featuring a new surface treatment called referenced acid etching (RAE). A total of 40 implants were placed in edentulous areas following predefined inclusion and exclusion criteria. Immediately after implant placement (t0), insertion torque, resonance frequency, digital periapical radiographs, and peri-implant evaluation were recorded. Resonance frequency analysis, periapical radiographs, and peri-implant evaluations were repeated after osseointegration (t1) and 180 d after rehabilitation (t2). The data obtained were statistically analyzed using specific tests for each type of analysis, with a significance level of 5%. Regarding the ISQ value at t1, it resulted in a high value, with a significant reduction at t2, for both types of connection, there was bone resorption for the HE and bone gain for the MT. The installation of the implants up to 180 d of prosthesis functionality, stability, bone gain or loss and type of bone, presented clinically acceptable conditions for all connections studied.