Esra Erkan, Şeniz Karaçay, Esra Çikler, İlayda Özge Polat
Turkish Journal of Orthodontics - 2025;38(4):233-243
Objective: To evaluate and compare the effects of low-intensity pulsed ultrasound (LIPUS), low-level laser therapy (LLLT), and their combined effects on sutural bone regeneration during rapid maxillary expansion (RME) of rats. Methods: Twenty-eight Sprague-Dawley rats were randomly assigned to four groups: LLLT group, LIPUS group, combination group, and control group. RME was performed on all groups for 11 days. The Both LLLT and LIPUS groups received their respective therapies (30 J/cm2), while the combination group received both therapies, each at 30 J/cm2. All treated rats received their doses on days 0, 4, and 8 and were sacrificed on day 11. Numbers of osteoblasts, capillaries, and osteoclasts were counted, and suture widths and areas of newly formed bone were measured histomorphometrically. General and cellular immunoreactivity of bone morphogenetic protein-2 (BMP-2), vascular endothelial growth factor (VEGF), and osteopontin (OPN) was evaluated by immunohistochemistry. Results: The number of osteoblasts was significantly higher in the combination group than in the control group (p<0.05). The combination group showed the highest general BMP-2 immunoreactivity and cellular VEGF immunoreactivity among all groups, and exhibited increased cellular OPN immunoreactivity compared with the control group (p<0.05). Both the area of newly formed bone (p<0.05) and suture width (p<0.01) were significantly greater in the LIPUS group than in the LLLT group. Conclusion: LIPUS is a more effective adjuvant therapy than LLLT for increasing sutural bone formation during RME. Combined therapy with LIPUS and LLLT has a synergistic effect and accelerates sutural bone regeneration by enhancing cellular activation more than either LIPUS or LLLT alone.
