Bone Resorption around Self-Tapping Implants in Bone Density Type I-II: 3-Years Results of a Prospective Clinical Study

Objectives: Placing self-tapping implants in High-density Bone (HDB) could increase the cortical stress during implant insertion enhancing periimplant bone resorption. There is a general consensus to avoid self-tapping implants use in HDB. This study assesses the success rate and clinical outcome of self-tapping implants in dense bone. Materials and Methods: This prospective single-blind controlled clinical trial was conducted on 26 patients who received 2-5 implants in the posterior mandible. Drilling protocol was adapted with the quality of existing bone. Patients were examined at the time of surgery (T1), 3 months post-operation (T2), 4 months post-surgery (T3), 12 months post-surgery (T4), 25 months post-surgery (T5) and 38 months post-operation (T6). Standardized radiographs were obtained at all time points. Three observers measured the crestal bone level changes. Data was analyzed using nonparametric statistics. Results: The success rate was 100% 3 years after placing self-tapping implants in HDB. Mean bone loss of -0.56 mm (CI 95% -0.69; -0.42) was observed from the time of surgery to the delivery of the crown. After the healing period during functional loading (at 4 to 38 months) there was only a mean bone level alteration of less than -0.04 mm per year. Conclusion: In this clinical study, all 90 self-tapping implants that have been placed in type I and type II bone were successful 3 years after placement, with minimal crestal bone level changes. Clinical relevance: Self-tapping implants can be successfully placed in HDB. However, clinicians must be aware of using a bone quality adapted drilling protocol.