A Comparison of the Low-Level Laser Versus Low Intensity Pulsed Ultrasound on New Bone Formed Through Distraction Osteogenesis

Abstract

Objective: To assess and compare the effects of low-intensity pulsed ultrasound stimulation (LIPUS) and low-level laser therapy (LLLT) on the bone mineral density (BMD) of bone formed through distraction osteogenesis (DO) using dual energy x-ray absorptiometry (DEXA). Background data: LIPUS and LLLT are noninvasive supporting treatment concepts used for wound healing. LIPUS has been used to accelerate bone healing through the therapeutic effect arising from piezoelectric and angiogenetic effects on cell membranes. LLLT known as "photobiomodulation'' is used in the treatment of soft and hard tissue injuries. Methods: The study was conducted with 15 New Zealand rabbits randomly divided into three groups of 5 according to treatment, as follows: Group A: DO was performed with no further treatment; Group B: DO was performed followed by 30mW/cm(2) LIPUS at 1 Mhz for 20 min/day during the distraction period; Group C: DO was performed followed by 25mW/cm(2) LLLT at 650 nm for 10 min/day during the distraction period. DEXA was used to examine the treated areas prior to surgery and at 30 and 60 days postoperatively. Results: In the control group, the mean BMD values at both 30 and 60 days postoperatively were below the baseline level, whereas they were above at the same time intervals in the LIPUS group. In the LLLT group, the mean BMD value at 30 days postoperatively was below the baseline level, whereas it was above the baseline level at 60 days postoperatively. Conclusions: LIPUS and LLLT applied during the distraction period accelerated the DO treatment.