Figure 1
LPLI promotes the proliferation of hPDL cells. (a) hPDL cells were treated with LPLI at doses of 0, 1, 2 or 4 J⋅cm−2. An MTT assay was performed, and the optical densities were measured (n=12). (b) LDH leakage was analyzed to evaluate cell cytotoxicity. There were no significant differences between the treatment groups (n=8). The data are shown as the mean±s.d. The levels of statistical significance are as follows: *P<0.05 and **P<0.01 relative to the control treatment group (0 J⋅cm−2); ##P<0.01 and ###P<0.001 relative to cultures treated with LPLI at 4 J⋅cm−2. hPDL, human periodontal ligament; LDH, lactate dehydrogenase; LPLI, low-power laser irradiation; MTT, 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide; OD, optical density.
