Histologic evaluation of low-intensity pulsed ultrasound effects on bone regeneration in sinus lift

PURPOSE Many techniques have been described for achieving vertical augmentation of the maxillary sinus. The aim of this study is to evaluate the effect of low-intensity pulsed ultrasound (LIPUS) to enhance bone regeneration after sinus floor elevation. METHODS The sinus lifting technique was performed through a lateral approach on 8 different sites of 5 patients (3 males and 2 females) and their mean age was 45.7 years old. The sites were randomly assigned to the control or test groups. The control group had 4 sites that received lateral sinus lifting procedure only, while the test group had 4 sites that received LIPUS application after the lateral sinus lifting procedure. 24-32 weeks (an average of 29 weeks) postoperatively, new bone formation in the augmented sinus sites was evaluated through histologic and histomorphometric analyses of the biopsy specimens obtained during implant placement. RESULTS In the test group, the mean percentage of newly formed bone was 19.0±2.8%. In the control group, the mean percentage of newly formed bone was 15.2±3.1%. The percentage of newly formed bone was approximately 4% higher in those cases where the sinus was treated by LIPUS than the percentage in those cases where it was not used. The difference was statistically significant. CONCLUSIONS Within the scope of this study, low-intensity pulsed ultrasound application after sinus lifting appeared to have a significant effect on the development of new bone formation.