Crestal bone loss around submerged and non-submerged implants during the osseointegration phase with different healing abutment designs: a randomized prospective clinical study.

ABSTRACT

OBJECTIVE: To evaluate peri-implant crestal bone loss during the osseointegration period, comparing submerged and non-submerged implants with healing abutments of different design. MATERIALS AND METHODS: A total of 90 Avinent®  dental implants (Avinent Implant System, Barcelona, Spain) were placed in 90 patients. All were sited in the posterior mandibular zone to replace teeth 3.6 or 4.6. Patients were divided randomly into three groups submerged (n = 30), non-submerged with anatomical healing abutment (n = 30), and non-submerged with esthetic healing abutment (n = 30). Peri-implant crestal bone loss was evaluated in intraoral radiographs taken at baseline, 1, and 3 months after implant placement. RESULTS: Peri-implant crestal bone loss at the end of the (3-month) osseointegration period was lowest in the submerged group (0.11 ± 0.14 mm), followed by the esthetic non-submerged group (0.15 ± 0.06 mm), but without statistically significant difference between these groups (P = 0.234). The greatest bone loss was produced in the non-submerged group with anatomical healing abutments (0.37 ± 0.12 mm), with significant differences between this group and the other two (P < 0.001). CONCLUSIONS: On the basis of these findings, bone resorption during the osseointegration period using the non-submerged technique varied significantly depending on the morphology of the healing abutment used. The non-submerged technique with an esthetic healing post-produced an equally predictable outcome compared with the submerged technique.