Bone gain after maxillary sinus lift: 5-years follow-up evaluation of the graft stability

Aim The aim of this study was to evaluate, through digital radiographic measurements, the long term changes in bone gain after maxillary sinus floor elevation surgery to obtain a stable and predictable volume augmentation for implant-prosthetic rehabilitation.Materials and Methods A retrospective study was conducted on 72 patients affected by atrophy of posterior maxilla. All patients were treated with a lateral wall approach, using 100% deproteinized bovine bone mineral (DBBM) as graft material, with simultaneous implant placement. Panoramic radiographs were taken immediately after the sinus floor augmentation procedure (t0) and after 5-years follow-up (t1). For the analysis, the distance from the implant platform to the apex of the grafted material in the maxillary sinus at t0 and t1 was detected (d).Results 166 implants were placed in patients ranging in age from 43 to 74 years. The results of this study showed a survival rate of 100%forall implants inserted. The mean change of "d" at t0 was 19.5 +/- 3.53 mm. The mean change of "d" at t1 was 18.25 +/- 4.25 mm. The mean of the difference between t1 and t0 resulted to be 1.37 +/- 0.138 mm. There was a statistically significant difference (p < .001) between measurements be-fore and after sinus regenerative therapy (paired t-test).Conclusions These results demonstrate that the graft material remained clinically and radiographically stable after 5-years follow-up, with an average vertical resorption of 1.37 +/- 0.138 mm.