Immediately loaded mini-implants supporting mandibular overdentures : a one-year comparative prospective cohort study

Abstract

Background: Little is known about differences between mini-implants and conventional immediately loaded implants for overdentures. Objectives: To compare clinical outcomes using two immediately loaded conventional or mini-implants for mandibular overdentures. Materials and Methods: Edentulous patients receiving either conventional (4.1 mm) or mini-implants (2.9 mm or less), based on available bone width were analyzed. All implants were immediately loaded with mandibular overdentures installed using locator attachments. Digital periapical radiographs for measuring marginal bone loss and clinical outcomes (ie, periodontal probing, plaque, and bleeding indices) were assessed at 1, 3, 6, and 12-month follow-up periods. Results: Fifty patients (25 receiving conventional implants—12 females, mean age of 65.3 ± 7.3 years; and 25 receiving mini-implants—11 females, mean age of 66.8 ± 8.1 years) was analyzed. Peak insertion torque (P = .001) and bone loss (P = .02), as well as change in plaque (P = .02) and bleeding (P = .04) indices at 12 months differed significantly between groups. Furthermore, linear regression revealed the height of the locator as a risk factor for bone loss (P = .038). Conclusions: The present findings suggest that two mini-implants are significantly more susceptible to bone loss after immediate loading, for which the height of locator might be considered a risk factor.