Osteotome sinus floor elevation without bone grafts--a 3-year retrospective study with Astra Tech implants.

BACKGROUND: The bone support for implants in the posterior part of the maxilla is often poor. This condition may be treated with augmentation of the maxillary sinus floor. The most common technique used is to elevate the sinus floor by inserting a bone graft through a window opened in the lateral antral wall. In 1994, a less-invasive technique using osteotomes was suggested by Summers.

PURPOSE: The aim of this study was to evaluate the clinical and radiographic outcome of implants placed in the posterior maxilla with the osteotome sinus floor elevation (OSFE) technique without grafting.

MATERIALS AND METHODS: The study population comprised 36 consecutive patients in whom 53 implants were inserted with the OSFE technique. The indication for sinus floor elevation was that the bone height below the maxillary sinus was considered to be 10 mm or less.

RESULTS: The mean height of the alveolar process in the intended implant sites was 6.3 ± 0.3 mm, and the mean elevation of the sinus floor was 4.4 ± 0.2 mm. Two implants in edentulous patients were lost at the 1-year follow-up, and one more at the 3-year examination. The remaining 50 implants inserted were in function, giving a 3-year cumulative survival rate of 94%. Implants used in single-tooth replacements and in partially edentulous cases had a 100% survival rate. The marginal bone level at the time of loading of the implants was 0.1 ± 0.04 mm below the reference point. One year later, the corresponding value was 0.5 ± 0.06 mm. The mean bone loss between the two examinations was 0.4 ± 0.05 mm. At the final examination after 3 years, the mean bone level was situated 0.6 ± 0.09 mm below the reference point, indicating a nonsignificant change between 1 year and 3 years.

CONCLUSIONS: The OSFE technique, without bone grafts, was found to produce predictable results in the treatment of 36 patients with restricted bone volume in the posterior part of the maxilla.