Effects of photobiomodulation with 450 nm and 635 nm laser wavelengths on the release of <scp>TGF</scp> ‐β, <scp>BMP</scp> ‐2, <scp>FGF</scp> ‐2, and <scp>VEGF</scp> from dental pulp stem cells

This study assessed the effects of photobiomodulation with 450 and 635 nm laser wavelengths on the release of transforming growth factor-beta (TGF-β), bone morphogenetic protein (BMP)-2, fibroblast growth factor (FGF)-2, and vascular endothelial growth factor (VEGF) from human dental pulp stem cells (DPSCs). In this in vitro study, human DPSCs were cultured and randomly assigned to two experimental groups to undergo 450 and 635 nm laser irradiation with 2, 4, and 6 J/cm² energy densities, and one control group (n = 5). After laser irradiation, total RNA was then extracted, cDNA was synthesized, and expression of TGF-β, FGF-2, BMP-2, and VEGF was assessed by real-time polymerase chain reaction (PCR). Data were analyzed by one-way and two-way ANOVA and Tukey's test (alpha = 0.05). The effects of laser wavelength, energy density, and their interaction were significant on the release of all growth factors (p < 0.0001). Laser irradiation in almost all subgroups increased the release of growth factors. By an increase in energy density, the release of BMP-2 and FGF-2 in both wavelengths, VEGF in the 635 nm group, and TGF-β in the 635 nm group increased while the release of VEGF in the 450 nm group decreased (p < 0.05). The amount of released growth factors in the 635 nm group was higher than in the 450 nm group (p < 0.05). PBMT with 450 and 635 nm lasers increased the release of TGF-β, BMP-2, FGF-2, and VEGF from human DPSCs in most energy densities, which may be of use in regenerative endodontics.