Primary Stability of Simultaneously Placed Dental Implants in Extraoral Donor Graft Sites: A Human Cadaver Study

Purpose: To compare the primary stability of dental implants placed in fibula, iliac crest, and scapula of human cadavers. Materials and Methods: Straumann Dental Implants (Institut Straumann, Basel, Switzerland) 4.1 mm × 10 mm in diameter were placed into bilateral fibula, iliac crest, and scapula of 4 fresh human cadavers. For the assessment of primary stability of implants, installation torque values (ITV) and removal torque values (RTV) were measured using a custom-made strain-gauged torque wrench, and resonance frequency analysis was carried out to quantify the implant stability quotients (ISQ). Bone specimens from each donor site were harvested to perform radiographic and histomorphometric analyses. Linear distance and optical density (OD) measurements were made on digitized parallel periapical radiographs and bone area fraction (BAF) was calculated on digitized images of decalcified histologic sections. Results: Fibula donor site presented higher ITVs and RTVs and cortical bone height for implants than other sites (P < .05). BAF measurements for iliac crest were higher than fibula and scapula bone donor sites. OD was higher in the iliac crest followed by scapula and fibula. Conclusion: The primary mechanical stability of implants placed in the fibula is higher than those placed in the iliac crest and the scapula, although the bone mass and density around implants in latter sites are higher.