Peri-implant bone loss clinical and radiographic evaluation around rough neck and microthread implants: a 5-year study.

OBJECTIVE: To evaluate marginal bone loss over 5 years around microthreaded implants placed in the maxillary anterior/esthetic zone and immediate restored with non-occlusal loading. MATERIALS AND METHODS: Seventy-one implants (with microthreads up to the platform-rough surface body and neck, internal connection and platform switching) were placed in healed bone in the maxillary arches of 30 men and 23 women (mean age 37.85 +/- 7.09 years, range 27-60). All subjects had at least 3 mm of soft tissue to allow the establishment of adequate biologic width and to reduce bone resorption. Each patient received a provisional restoration immediately after implant placement with slight occlusal contact. Mesial and distal bone height was evaluated using digital radiography on the day following implant placement (baseline) and after 1, 2, 3, 4 and 5 years. Primary stability was measured with resonance frequency analysis. RESULTS: No implants failed, resulting in a cumulative survival rate of 100% after 3 years. Marginal bone loss from implant collar to bone crest measured at baseline (peri-implant bone defect at the fresh extraction socket) and after 5 years was 0.90 mm +/- 0.26 mm. Mesial and distal site crestal bone loss ranged from 3.42 +/- 1.2 mm at baseline to 3.51 +/- 1.5 mm after 5 years and from 3.38 +/- 0.9 mm at baseline to 3.49 +/- 0.9 mm after 5 years, respectively (P = 0.086). CONCLUSIONS: The results of this study showed limited implant crestal bone loss 0.90 mm +/- 0.26 mm and 100% of implant survival rate at 5-year follow-up of immediate restored implants with rough surface neck and microthreads.