https://www.selleckchem.com/products/epz020411.html 05）, and group 7 was the largest. There was significant difference among group 4, 5, 6 in average energy absorption ratio（P less then 0.05）, among which group 4 and group 5 were larger. CONCLUSIONS 3 mm splint is good enough to be used to make mouthguard, which is also thinner and more comfortable. Splint of soft material is more suitable for mouthguard than splint of hard material.PURPOSE To investigate the effect of low-magnitude high frequency vibration (LMHFV) on proliferation, migration ability and osteogenic differentiation of human periodontal ligament stem cells(hPDLSCs). METHODS hPDLSCs were isolated from premolar and randomized into vibration culture group (magnitude：0.3 g; frequency：40 Hz; time：15 min/24 h) and static culture group. CCK-8 was used to identity the proliferation of hPDLSCs. Wound-healing assay was used to evaluate migration ability of hPDLSCs. The osteogenesis gene expression was analyzed by RT-PCR, and the osteogenesis protein expression was analyzed by Western blot. The osteogenesis differentiation capability was evaluated by alizarin red staining. The data were analyzed using SPSS 21.0 software package. RESULTS After LMHFV, the proliferation and migration ability of hPDLSCs were increased. The expression level of RUNX2, ALP, Col-1, and OCN was significantly augmented under LMHFV. Alizarin red staining and Western blot proved the same trend. CONCLUSIONS：The results demonstrate that LMHFV can promote hPDLSCs proliferation, migration ability and osteogenic differentiation.PURPOSE To explore the combined effect of recombinant human transforming growth factor-β1 (rhTGF-β1) and recombinant human platelet derived growth factor-BB (rhPDGF-BB) on the expression of Pyk2 in the osteoclasts of the pressure side of orthodontic tooth in rats. METHODS One hundred and sixty male Sprague-Dawley rats were randomly divided into 2 groups experimental group(A) and control group(B) to establish orthodontic t