The use of a piezoelectric ultrasonic osteotome for internal sinus elevation: a retrospective analysis of clinical results.

PURPOSE: To explore the possibility and evaluate the clinical outcome of accomplishing maxillary internal sinus floor augmentation through the use of a piezoelectric osteotome in conjunction with dental implant placement and to discuss this technique. MATERIALS AND METHODS: Patients attending the outpatient clinic of the Department of Dental Implantology, Hospital of Stomatology, Tongji University, between July 2007 and September 2009, who had insufficient bone volume to harbor endosseous implants at least 8 mm long in the lateral/posterior maxilla because of sinus pneumatization were enrolled in the study. Sinus augmentations were accomplished with a piezoelectric osteotome, followed by implant placement, either immediately or delayed (6 months after augmentation, if the residual ridge height was less than 4 mm). RESULTS: Thirty patients with 36 maxillary molar sites with insufficient alveolar bone height as a result of pneumatization of the sinus were included in this study. The residual vertical bone height ranged from 2 to 8 mm. Twenty-eight implants were placed into 24 patients immediately after sinus augmentation. Another eight implants were placed into 6 patients 6 months after sinus augmentation. Only one sinus membrane perforated (failure rate: 2.78%). Only one implant was lost during the observation period. No other implant mobility or rapid bone loss was seen during a follow-up period of 5 to 27 months. CONCLUSIONS: Application of a piezoelectric osteotome for internal sinus elevation simplified manipulation of the membrane and greatly reduced the chance of perforation. The pressure gradient between sinus and implant cavity was helpful in accomplishing this technique.