2015 Volume 26 Issue 1 Pages 1-9
Laser irradiation activates a range of cellular processes in a variety of cell types, including stem cells, and can promote tissue repair.
The purpose of this study was to examine the effects of diode laser irradiation on the proliferation and osteogenic differentiation of human dental pulp cells (hDPCs). hDPCs were cultured and exposed to an 810-nm diode laser at a dose of 0 or 1 J/cm2. Cell proliferation was evaluated by cell proliferation ELISA BrdU kit and MTS assay. For osteogenic differentiation, hDPCs at confluence were cultured in osteoblastic differentiation medium (ODM), and were irradiated daily with a diode laser. mRNA and protein levels of bone markers were examined by real-time PCR analysis and Western blot analysis, respectively, Alkaline phosphatase (ALP) activity and calcium concentration were determined. Mineralization was evaluated by Alizarin Red staining. Cell proliferation was enhanced significantly (P < 0.01) by treatment with laser irradiation. mRNA levels of ALP, type I collagen and dentin sialoprotein (DSP) in hDPCs treated with laser irradiation became significantly (P < 0.01) higher compared with non-treated controls. Treatment of hDPCs with laser irradiation also enhanced significantly (P < 0.01) ALP activity and calcium concentration, resulting in enhanced mineralization, as evidenced by the high intensity of Alizarin Red staining.
In conclusion, the present study showed that 810-nm diode laser irradiation may contribute to the regeneration of dental pulp by enhancing hDPC proliferation and differentiation.
