Fig. 6

Effect of LLLT, LIPUS, and combination on gene expression of rat’s maxilla at days 1, 3, 7, 14, and 21. The gene expression for RANKL, RANK, OPG, and RUNX2 was determined by using semi-quantitative RT-PCR and normalized by GAPDH for the following groups: non- treatment, orthodontic control, LLLT (100 mW), LIPUS, and (LLLT + LIPUS). All genes were significantly upregulated in the treatment groups in relation to the orthodontic controls. Between the treatment groups, RANKL and RANK were the highest in the combination group followed by the LLLT group. For OPG and RUNX2, the combination group was the highest and followed by the LIPUS group. The data are shown as the mean ± SEM of three separate experiments. *P ≤ 0.05 between groups