Laser and LED photobiomodulation effects in osteogenic or regular medium on rat calvaria osteoblasts obtained by newly forming bone technique

The purposes of this study are to evaluate the effects of photobiomodulation (PBM) with laser and LED on rat calvaria osteoblasts (rGO lineage), cultured in osteogenic (OST) or regular (REG) medium, after induction of a quiescent state and to test if PBM is capable of osteogenic induction and if there is a sum of effects when combining OST medium with PBM. Before irradiation, the cells were put in a quiescent state (1% FBS) 24 h, when red (AlGaInP—660 nm) and infrared laser (GaAlAs—808 nm) and LED (637 ± 15 nm) were applied. The groups were as follows: red laser (RL3—5 J/cm2, 3 s and RL5—8.3 J/cm2, 5 s, 1.66 W/cm2); infrared laser (IrL3—5 J/cm2, 3 s and IrL5–8.3 J/cm2, 5 s); LED (LED3—3 s and LED5—5 s, 0.02 J/cm2, 0.885 W/cm2); positive (C+, 10% FBS) and negative control (C−, 1% FBS). For alkaline phosphatase (ALP) and mineralization assays, the cells were cultured in REG (DMEM 10% FBS) and OST medium (DMEM 10% FBS, 50 μg/mL ascorbic acid, 10 mM β-glycerophosphate). Statistical analysis was performed using ANOVA and Tukey’s tests (p