Na, SungsooTruongVo, ThucNhiJiang, FeifeiJoll, Jeffery E.Guo, YunxiaUtreja, AchintChen, Jie2019-03-282019-03-282018-07Na, S., TruongVo, T., Jiang, F., Joll, J. E., Guo, Y., Utreja, A., & Chen, J. (2018). Dose analysis of photobiomodulation therapy on osteoblast, osteoclast, and osteocyte. Journal of Biomedical Optics, 23(7), 075008. https://doi.org/10.1117/1.JBO.23.7.075008https://hdl.handle.net/1805/18713The objective of this study was to evaluate the effects of varying light doses on the viability and cellular activity of osteoblasts, osteocytes, and osteoclasts. A light application device was developed to apply 940-nm wavelength light from light-emitting diodes on three cultured cells, MC3T3-E1, MLO-A5, and RANKL-treated RAW264.7 cells. The doses (energy density) on cells were 0, 1, 5, and 7.5  J  /  cm<sup>2</sup>. The corresponding light power densities at the cell site were 0, 1.67, 8.33, and 12.5  mW  /  cm<sup>2</sup>, respectively, and the duration was 10 min. The results showed that the three cell types respond differently to light and their responses were dose dependent. Low-dose treatment (1  J  /  cm<sup>2</sup>) enhanced osteoblast proliferation, osteoclast differentiation, and osteoclastic bone resorption activity. Osteocyte proliferation was not affected by both low- and high-dose (5  J  /  cm<sup>2</sup>) treatments. While 1  J  /  cm<sup>2</sup> did not affect viability of all three cell types, 5  J  /  cm<sup>2</sup> significantly decreased viability of osteocytes and osteoclasts. Osteoblast viability was negatively impacted by the higher dose (7.5  J  /  cm<sup>2</sup>). The findings suggest that optimal doses exist for osteoblast and osteoclast, which can stimulate cell activities, and there is a safe dose range for each type of cell tested.enPublisher PolicyphotobiomodulationosteoblastosteocyteDose analysis of photobiomodulation therapy on osteoblast, osteoclast, and osteocyteArticle