Effect of low-level laser therapy on proliferation and cytotoxicity of mouse fibroblasts and human fibroblasts: An study.

BACKGROUND

Diode laser is known for its biostimulatory effects on various cell populations such as osteoblasts and fibroblasts. The usage of low-level laser therapy for photobiomodulation depends on its type, emission wavelength, and energy selected. Previously performed studies have determined its effect on cell proliferation and cytotoxicity; however, the results were inconsistent.

OBJECTIVES

The objectives of this study were to evaluate and compare diode laser effect on mouse embryonic fibroblasts (MEFs) and human gingival fibroblasts (HGFs) for proliferation and cytotoxicity.

MATERIALS AND METHODS

32 samples, 16 wells of MEF cells (Group I) and HGF cells (Group II) each with 8 subgroups containing control (no laser irradiation) and experimental (laser irradiated) groups were cultured after being seeded at 4000 cells/ well with 4cm inter-well distance. Experimental group cell cultures were irradiated with a single dose of 810 nm diode laser (energy 1J/cm, 12.5 mW, 80 s/well) using continuous wave mode after 1 day of incubation. Spectrophotometric analysis was done after 24 h of laser irradiation for cell proliferation and cell cytotoxicity on the 2, 3, and 7 days on all groups.

RESULTS

Human and mouse fibroblast groups showed positive results when irradiated with an 810 nm laser. A hundred percent proliferation was seen for MEF in 7 days and HGF in 2 days. Two percent cytotoxicity was seen on the 2 and 3 day in MEF. Increased cell proliferation and minimal cytotoxic effects were seen with diode laser usage.

CONCLUSION

Low-level laser irradiation indicates an increase in cell proliferation with less cytotoxicity on mouse and human fibroblasts.