Short (6-mm) dental implants versus sinus floor elevation and placement of longer (≥10-mm) dental implants: a randomized controlled trial with a 3-year follow-up.

Abstract

To investigate whether short (6-mm) dental implants could be an alternative to sinus floor elevation (SFE) and placement of longer (≥10-mm) implants in the posterior maxilla. Over a 3-year period, all patients presenting with partial edentulism in the posterior maxilla were considered for inclusion in this randomized controlled trial. Patients were randomly chosen either to receive short (6-mm) implants (test group [TG]) or to undergo SFE with simultaneous placement of standard-length (≥10-mm) implants (control group [CG]). SFE was performed using the lateral technique. In both groups, tapered implants (AnyRidge, MegaGen, Gyeongbuk, South Korea) were placed. All implants were loaded after 4months of healing. At each annual follow-up session, clinical and radiographic parameters were assessed. Primary outcomes were implant survival, stability (measured with the implant stability quotient [ISQ]), marginal bone loss (MBL), and complications; secondary outcomes were patient satisfaction and treatment time and cost. Thirty-three patients were assigned to the TG and 20 to the CG. Forty-five implants were inserted in each group. At 3years, implant survival rates were 100% and 95.0% for the TG and CG, respectively; this difference was not statistically significant (P=0.38). The mean ISQ values of the TG and CG did not differ at placement (68.2 vs. 67.8, P=0.1), at delivery of the final restoration (69.5 vs. 69.4, P=0.9), and after 1year (71.0 vs. 71.5, P=0.1); at 3years, the CG had a significantly higher mean ISQ than the TG (72.4 vs. 71.6, P=0.004). Mean MBL was significantly higher in the CG than in the TG, both at 1year (0.14mm vs. 0.21mm, P=0.006) and at 3years (0.20mm vs. 0.27mm, P=0.01). A few complications were reported. Surgical time and cost were significantly higher in the CG than in the TG (P<0.0001). Patient satisfaction was high in both groups. In this randomized controlled trial, results for short (6-mm) implants were similar to those for longer (≥10-mm) implants in augmented bone. Short implants might be preferable to SFE, because the treatment is faster and less expensive. Long-term randomized controlled trials are required to confirm these results.