Short implants in posterior jaws. A prospective 1-year study

Background: There is limited evidence for the outcome of short implants (7 mm) to rehabilitate posterior jaws. Purpose: To report on the outcome of 7 mm short implants in the rehabilitation of posterior areas of atrophic jaws 1 year after loading. Materials and methods: This prospective study included 127 patients treated with 217 implants supporting 165 fixed prostheses. Final abutments were delivered at surgery stage, and in 11 patients (18 implants) a provisional acrylic resin crown or bridge was manufactured and attached to the implants on the same day as the surgery, achieving immediate function. The final prosthesis was typically delivered after 6 months. Outcome measures were implant survival calculated at patient and implant levels, complications and pen-implant marginal bone resorption calculated at patient level. Results: Three patients with 5 implants were lost to follow-up after 7 months. Implant losses occurred in 6 of the 127 patients and 10 of the 217 implants placed failed, giving a success rate of 95% at patient and implant level after 1 year of follow-up. The mean marginal bone resorption after 1 year of follow-up was 1.27 mm (SD = 0.67 mm). The only complication registered was a peri-implant pathology at one implant. Conclusions: One year after loading, 7 mm short implants provided good success rates (95% at patient level and implant level) suggesting that the use of short implants is a viable concept, however longer follow-ups are needed to confirm these preliminary results.