Seven mm long dental implants in posterior jaws: 3-year report of an ongoing prospective single cohort study

To report on the outcome of 7 mm long implants in the rehabilitation of posterior areas of atrophic jaws 3 years after loading.

This prospective study included 127 patients treated with 217 implants supporting 165 fixed prostheses. Final abutments were delivered at surgery stage and in the large majority of patients (n = 116) the implants (n = 199) were loaded after 4 months. Primary outcome measures were implant success and prosthetic success calculated at patient level; secondary outcome measures were complications, and marginal bone level changes calculated at patient level.

Thirteen patients with 21 implants dropped out of the study after 3 years. Implant losses occurred in 10 of the 127 patients and 14 of the 217 implants placed failed, giving a cumulative success rate of 93.7% at 3 years, using the patient as unit of analysis. Eight prosthetic failures occurred in six patients, rendering a prosthetic success rate 95.3% at patient level. The average (standard deviation) marginal bone resorption after 3 years of follow-up was 1.46 mm (0.78 mm). Complications occurred in 13 patients (10.2%) and 15 implants (6.9%).

Within the limitations of this study, 7 mm long implants in posterior atrophic jaws can be a viable treatment option given the good prosthetic and implant success rates, low marginal bone loss and low incidence of complications. Nevertheless, longer follow-ups are needed to validate the long-term outcome. Conflict-of-interest statement: This study was funded by grant no. 2015-1378 from Nobel Biocare Services. Paulo Maló is currently a consultant for Nobel Biocare. The remaining authors declare no conflicts of interest.