Implant Insertional Torque Values Predict Outcomes

Purpose: To study the relationships between insertional torque values (ITVs) recorded during implant placement and implant healing times and cumulative survival rates. Materials and Methods: This retrospective study evaluated 174 Osseotite 6.0-mm-diameter, straight-wall, threaded dental implants (BIOMET 3i, Palm Beach Gardens, FL) placed in 172 consecutive patients by the primary author. All implants were placed immediately into mandibular first or second molar extraction sockets after extraction. ITVs were recorded at placement. Implants were evaluated 3 months after surgery before discharge to restorative dentists for restoration. The post-restorative follow-up ranged from 2 years 1 month to 4 years 8 months (median and mean of 3 years 1 month [SD, 4.95]). Results: Of the implants, 3% (n = 5) were removed at the time of surgical placement because of perceived clinical mobility of the implants within the osteotomies. The implants that were stable at the time of implant placement (n = 169) were placed into 1 of 3 groups relative to the specific ITVs at implant placement: group 1, low ITV, 29% (n = 49); group 2, medium ITV, 23% (n = 39); and group 3, high ITV, 48% (n = 81). Cumulative survival rates for each group were 86% for low ITV, 90% for medium ITV, and 96% for high ITV (P =.0302). At the scheduled 3 months' follow-up visit, 33% of the low ITVs, 21% of the medium ITVs, and 5% of the high ITVs required an additional 3 months of healing. Conclusion: In this study ITVs measured through surgical handpieces during implant placement provided meaningful real-time feedback that aided the surgeon regarding implant survival and determining unloaded healing times on a case-by-case basis. (C) 2011 American Association of Oral and Maxillofacial Surgeons J Oral Maxillofac Surg 69:1344-1349, 2011