Effect of low intensity pulsed ultrasound on the gene expressions of bone differentiation markers in human periodontal ligament fibroblasts

Abstract

Low intensity pulsed ultrasound (LIPUS) has been demonstrated to accelerate bone growth during fracture healing and distraction osteogenesis. This study was to evaluate the effect of LIPUS on the alteration of the expressions of osteogenesis related genes in human periodontal ligament fibroblasts (hPDLFs) using the polymerase chain reaction (PCR) method. HPDLFs were pre-cultured for eight days in the presence of differentiation media and then exposed to LIPUS for 7 days each 15-min. 6 passages of hPDLFs were used in this study. RT-PCR was used to determine the effect of LIPUS on expression of several genes associated with bone differentiation markers in hPDLFs. The expression of the genes was increased compared to controls. Increases in both gene expressions and bone nodule formation were greatest at 7 days after last LIPUS exposure, implying that there may be a time dependence for the stimulus of bone differentiation markers in hPDLFs. LIPUS treatment could accelerate the differentiation of the hPDLFs into osteoblasts or cementoblasts. In the future, attempts to stimulate bone defect healing and periodontal tissue remodelling using LIPUS may focus on the use of other treatment protocols.