Maxillary Sinus Lift for Single Implant-Supported Restorations: A Clinical Study

Purpose: The aim of this study was to evaluate single-tooth implant-supported restorations placed in conjunction with several methods of maxillary sinus augmentation. Materials and Methods: A retrospective review was conducted of all consecutively treated patients who received single-implant tooth rehabilitation in combination with sinus augmentation. Implant survival rate and peri-implant conditions, such as marginal bone resorption (mm), pocket depth (mm), Plaque and Bleeding Indices, and Periotest values, were compared for the different augmentation procedures. Results: Fifty-one patients were treated with 54 screw-type single implant-supported restorations in the posterior maxilla in combination with isolated sinus floor augmentation. Depending on the residual ridge height and the intended augmentation height, sinus lift elevation was performed either in a 1-stage lateral approach (25 patients, 28 implants), in a 2-stage lateral approach (12 patients, 12 implants), or with the osteotome technique (14 patients, 14 implants). The predominant use of long implants provided for a favorable implant-crown ratio (> 1.0) and produced an overall clinical survival rate of 100% over the observation period (44.5 ± 22.7 months), with no differences between the augmentation procedures and implant types used. The most frequent site for single-tooth replacement in combination with sinus floor augmentation was the first molar region (61%). Implants with wider diameters (94% >= 4.3 mm) were used in this region. The most frequent intraoperative complication was tearing of the sinus membrane (58%) as a result of the restricted access for the lateral 1- or 2-stage approach, and the most frequent prosthetic complication was crown loosening. Conclusion: On the basis of this retrospective review, the following was observed: (1) Successful function and excellent peri-implant parameters may be anticipated for single implant-supported restorations placed in conjunction with sinus elevation procedures. (2) Clinical and radiographic examinations demonstrated similar conditions for single-tooth restorations despite the use of different surgical approaches to sinus augmentation. (More than 50 references.) Keywords: lateral approach, osteotome technique, single implant-supported restorations, sinus augmentation