## 4 Discussion
[One-way ANOVA and [PERSON]’s supplementary tests were used to compare the study groups with the control]. irradiation, and cells were incubated at 42 \({}^{\circ}\)C; both works eliminated the effect of the 980 nm wavelength but had no impact on the 810 nm wavelength. They concluded that the 980 nm wavelength affected temperature-dependent calcium channels, but the 810 nm wavelength had the greatest impact on mitochondrial cytochrome c oxidase [38]. In research performed by [PERSON] et al. in 2020, they investigated near-infrared (940 nm) photobiomodulation on stem cells derived from a Buccal Fat Pad. In this research, after separating the cells from the sample of the human BFP, the third passage of the cells was irradiated twice a day for three consecutive days. Irradiation was performed with six different laser settings. These settings consisted of two continuous pulse conditions (50% cycle), energy densities of 3 and 6 J/cm\({}^{2}\), and two different output powers (0.1 W and 0.3 W). This experiment was repeated on three different days and each time, the cells were evaluated and repeated using a MTT assay at intervals of 24, 48, and 72 h. The highest proliferation was observed in 3 J/cm\({}^{2}\), 0.3 W, pulsed radiation at 24 h and 48 h; however, after 72 h, the greatest increased proliferation was related to 6 J/cm\({}^{2}\), 0.1 W, pulsed. This setting was used for the osteoporotic differentiation method. Microscopic analysis of Alizarin red staining showed that cells under 3 J/cm\({}^{2}\), 0.3 W pulse irradiation also increased the mineralization of BFPSCs cultured in an osteogenic induction medium compared to the negative control [39]. In our research, we concluded that the wavelength of 980 nm (0.1 W) with an energy density of 4 J/cm\({}^{2}\) compared on the fifth day was significant compared to other energy densities. As both wavelengths are in the near-infrared region, they can be used for the proliferation of BFP stem cells. In the study by [PERSON] et al., the effect of PBM on proliferation, viability, and osteogenic differentiation in stem cells isolated from human PDL was investigated, and the 940 nm diode laser with an energy density of 4 J/cm\({}^{2}\) and a power of 100 mW was used for three sessions every 48 h. Cell viability was evaluated 24, 48, and 72 h later. In this research, the cells were divided into three groups: C\(-\): without osteogenic medium, C\(+\): with osteogenic medium and without laser, and L\(+\): with osteogenic medium and laser. In this research, the results of MTT did not show a difference between the control and study groups. However, after 14 and 21 days, both the C\(+\) and L\(+\) control groups showed an increase in mineral tissue formation compared to the C\(-\) group [40]. In the current study, the same energy density and power were used, but the wavelength we used was 980 nm, the radiation was done in two sessions, and the stem cell used was human BFP. In the current study, the wavelength of 980 nm on the fifth day was significant compared to the control group. In the study of [PERSON] et al., the effect of PBMT and mesenchyme stem cells on bone regeneration was investigated. In this research, 48 lesions with a diameter of 6 mm were created in rabbit calvarial bone. These lesions were divided into four groups: no treatment, treatment with PBMT, treatment with mesenchyme stem cells, and a combination of stem cells and laser. The wavelength of the laser was 810 nm, the power density was 0.2 W/cm\({}^{2}\), and the energy density was 4 J/cm\({}^{2}\). In this research, it was concluded that the group that was only under laser radiation produced significant results compared to the other two groups and the control group. In addition, the amount of inflammation decreased significantly in the group treated with laser compared to the other two treatment groups [41]. Our study used a different cell source, and the wavelength was 808 nm. IN addition, the power density was 0.4 W/cm\({}^{2}\), although the energy density was similar.