Stability of implants placed at sites treated with bone allograft

• Main Author: Tuckey, Tanya Danielle
• Language: English
• Published: University of British Columbia 2012
• Online Access: http://hdl.handle.net/2429/42807

Objective: A retrospective chart review was performed to assess the stability of implants in a variety of clinical situations, including placement at sites with a history of bone augmentation using bone allograft. Methods: The study included 286 implants placed by an experienced practitioner and by Graduate Periodontics residents at the University of British Columbia. Implants included a variety of Nobel Biocare, Straumann, and Astra Tech designs. The Osstell ISQ device was used to measure implant stability (RFA) by emitting magnetic pulses that cause a SmartPeg attached to the implant to resonate according to the stability of the implant. Results were displayed in Implant Stability Quotient (ISQ) units and were recorded in triplicate, from the buccal, lingual, mesial, and distal. Measurements obtained at second surgery were compared with factors related to bone grafting, as well as patient demographics, implant site, and physical implant characteristics (significance p<0.05). Results: The overall implant survival rate was 98.9% with 3 implant failures. There was good reproducibility of measurements taken in triplicate and measurements taken from the buccal were significantly lower than those taken from either the mesial or distal. A significantly higher ISQ was obtained in the mandible than the maxilla, with significantly lower values at incisor sites compared with both premolar and molar sites. A higher ISQ was obtained for short implants and this reached statistical significance in the mandible, where shorter implants tended to be wider. Significantly lower ISQ values were obtained for narrow implants in both arches. ISQ values in soft bone were significantly lower, as were values at sites with a history of lateral ridge augmentation using xenograft. No significant difference was observed between ISQ and age, gender, Type 2 diabetes, smoking, implant type, insertion torque, buccal bony dehiscence, surgeon’s level of experience, or whether the site had a history of lateral ridge augmentation, socket preservation, or sinus lifting. Conclusions: Implant stability, as measured using the Osstell ISQ device, is not significantly affected by a history of bone grafting using bone allograft. Stability is, however, affected by implant dimensions, implant site, and bone density.