Effect of low-intensity pulsed ultrasound after intraoral vertical ramus osteotomy.

OBJECTIVE: The present study investigated the effect of low-intensity pulsed ultrasound (LIPUS) on long-term osseous healing of the cleavage space between bone fragments after intraoral vertical ramus osteotomy (IVRO). STUDY DESIGN: Patients undergoing IVRO were randomly assigned to the LIPUS group (n = 12) or the control group (n = 9) after surgery. LIPUS treatments were applied daily to the cleavage space between bone fragments for 3 weeks. We observed 3-dimensional quantitative color mapping of the whole mandible created by computed tomography (CT) data at 1 month, 6 months, and 1 year postoperatively. On the basis of CT values, the color grades were classified as D1 to D5 by using the Misch criteria. We then calculated mean CT values and rated each color grade in different selection ranges. RESULTS: The mean CT values of the LIPUS group were significantly higher than those of the control group at 1 month, 6 months and 1 year postoperatively (P < .01). The color grades of the cleavage between bone fragments increased from D5 to D1 over time. CONCLUSIONS: Our results indicated that LIPUS promoted osseous healing after IVRO, thus improving bone density and offering clinical benefits.