A prospective study evaluating a protocol for 6 weeks' loading of SLA implants in the posterior maxilla: one year results.

Experimental and clinical studies have shown that modification of implant surfaces can result in increased bone-to-implant contact at earlier times thus reducing the healing period between surgery and prosthesis. Sandblasted and acid-etched (SLA) implants are in this category and have successfully undergone early loading in patients with good bone quality and quantity. Nevertheless, premature loading of SLA implants was not routinely possible in predominantly trabecular bone, such as the posterior maxilla, as it is often characterized by a deficiency in initial bone to implant contact. The purpose of this prospective clinical investigation is to evaluate the efficacy of a modified surgical protocol followed by loading SLA implants at 6 weeks in the posterior maxilla. Drilling was limited to the minimum, and most of the site preparation was produced with osteotomes. Screw tapping was never performed and primary stability was always achieved. Abutment connection was carried out at 15 Ncm 43 (+/- 1) days after surgery and provisional restoration was fabricated. Further abutment tightening at 35 Ncm was performed after an additional 6 weeks. Of the 36 SLA implants placed in 19 patients, one was lost before final restoration. Clinical and radiographic measures were taken at baseline and 1 year postoperatively. The preliminary results suggest that, by means of the surgical and restorative technique presented, SLA implants are suitable for loading at 6 weeks in the posterior maxilla. More years of observation will verify whether osseointegration can be equally maintained over a long period.