Dental pulp stem cells (DPSCs) can undergo several types of differentiation, including osteogenic differentiation. One osteogenesis-inducing factor that has been previously described is in vitro low-power laser irradiation of cells. Laser irradiation promotes the acceleration of bone matrix mineralization of the cell strain. However, no consensus exists regarding the dose and treatment time. We used DPSC strains from cleft lip and palate patients because new bone tissue engineering strategies have used DPSCs in preclinical and clinical trials for the rehabilitation of alveolar bone clefts. Optimizing bone tissue engineering techniques for cleft and lip palate patients by applying low-power laser therapy (LPLT) to DPSCs obtained from these patients can help improve current strategies to quickly close large alveolar clefts. The aim of this study was to investigate the effects of LPLT at different energy densities in DPSC strains obtained from cleft lip and palate patients during in vitro osteogenic differentiation. Ten DPSC strains were obtained from cleft lip and palate patients and then used in the following study groups: group 1: control, the strains underwent osteogenic differentiation for 21 days; and groups 2, 3, and 4: the strains were irradiated each day with a low-power red laser (660 nm) (5, 10, and 20 J) during 21 days of osteogenic differentiation. Using Bonferroni's test, a statistically significant difference in the mean values was found between the irradiated groups (2, 3, and 4) and the control group (p < 0.001). However, no significant difference in osteogenic potential was found among the irradiated groups. Our findings showed that the osteogenic potential of DPSCs increases with red laser irradiation at 5, 10, and 20 J, and this treatment could be considered a new approach for preconditioning these cells to be used in bone tissue engineering.
Keywords: bone regeneration; dental pulp stem cell; low-power laser; mesenchymal stem cells; osteogenic differentiation.