Assessment

In order to achieve an adequate oral rehabilitation after reconstruction of the jaw, a consistent prosthetic treatment is necessary. The main determinants of implant stability are the mechanical properties of the bone tissue at the implant site, and how the contact between the implant neck and the cortical bone plate is achieved. If we presume a correct surgical technique and a good implant design, the bone density determines the primary implant stability at the time of surgery. A stable implant can exhibit different degrees of displacement or resistance to load, which corresponds to varying degrees of stability. Conversely, a failed implant shows clinical mobility on the macroscale, as the implant is surrounded by a fibrous scar tissue. An increasing degree of micro-mobility is present until clinical failure of the implant. This suggests that techniques to measure and to monitor implant micro-motion/stability could give the clinician the opportunity to optimize implant treatment. Insertion torque, Periotest, and resonance frequency analysis are suitable to measure primary implant stability. Nevertheless, the resonance frequency analysis is the only method that can detect variations in different bone densities, which may be measured even during the follow-up of the implant.