Matthias Karl*,Friedrich Graef,Werner Winter
Dental implants lacking primary stability show increased levels of micromotion which may result in fibrous encapsulation instead of osseointegration. A novel experimental technique has been used for directly measuring implant displacement as a consequence of occlusal loading. Implants were inserted in bone surrogate material differing in density thereby measuring insertion torque and implant stability by means of resonance frequency analysis. Implants placed in bone with a density of 10 pcf and loaded with a mean force of 62.7 N showed maximum mean displacement of 71.9 μm. Significant differences in micromotion resulted from placing implants in bone with varying densities. Measurements of implant insertion torque correlated well with measurements of implant displacement. Implant stability measurements of specific implants showed consistency, no correlation between implant stability and maximum implant displacement could be established. It appears that a reliable assessment of bone quality may be best used for predicting micromotion at the implant-abutment interface.