A 10-year Randomized Clinical Trial on the Influence of Splinted and Unsplinted Oral Implants Retaining Mandibular Overdentures: Peri-implant Outcome
Ignace Naert, DDS, PhD/Ghada Alsaadi, DDS/Daniel van Steenberghe, MD, DDS, PhD, Dr hc/Marc Quirynen, DDS, Ph
Purpose: This randomized controlled clinical trial aimed to evaluate the efficacy of splinted implants versus unsplinted implants in overdenture therapy over a 10-year period. Materials and Methods: The study sample comprised 36 completely edentulous patients, 17 men and 19 women (mean age 63.7 years). In each patient, 2 implants (Brånemark System, Nobel Biocare, Göteborg, Sweden) were placed in the interforaminal area. Three to 5 months after placement, they were connected to standard abutments. The patients were then rehabilitated with ball-retained overdentures, magnet-retained overdentures, or bar-retained overdentures (the control group). Patients were followed for 4, 12, 60, and 120 months post–abutment connection. Group means as well as linear regression models were fitted with attachment type and time as classification variables and corrected for simultaneous testing (Tukey). Results: After 10 years, 9 patients had died and 1 was severely ill. Over 10 years, no implants failed. Mean Plaque Index, Bleeding Index, change in attachment level, Periotest values, and marginal bone level at the end of the follow-up period were not significantly different among the groups. Discussion: The annual marginal bone loss, excluding the first months of remodeling, was comparable with that found around healthy natural teeth. Conclusion: The fact that no implants failed and that overall marginal bone loss after the first year of bone remodeling was limited suggested that implants in a 2-implant mandibular overdenture concept have an excellent prognosis in this patient population, irrespective of the attachment system used.