Correlation between dental implant insertion torque and mandibular alveolar bone density in osteopenic and osteoporotic subjects

Purpose: Osteoporotic patients require particular attention during implant placement, and insertion torque (IT) has been established as a simple and noninvasive method to assess local bone quality and primary implant stability. This study aimed to test the hypothesis that IT was not significantly correlated with bone density, as assessed with computed tomography, in a group of osteopenic and osteoporotic patients. In addition, the hypothesis that IT was not significantly correlated with implant length was tested. Materials and Methods: Fifty-three completely edentulous patients with compromised bone mineral density (osteoporotic or osteopenic) who required treatment with complete maxillary dentures and complete mandibular implant supported overdentures participated in the study. Each patient received two screw-shaped self-tapping implants (Branemark Mark III TiUnite) at the mandibular canine regions. The IT of each implant during placement was recorded. The Pearson correlation between IT and implant site bone density (Hounsfield unit) obtained from presurgical computed tomographic scans was analyzed. The relationship between IT and implant length was also studied. Results: IT was significantly correlated to implant site bone density but not to implant length. Conclusion: IT can be a viable and practical means to assess mandibular bone quality in patients with compromised general bone density