EFFECTS OF PHOTOBIOMODULATION PROTOCOLS ON STEM CELLS FROM HUMAN EXFOLIATED TEETH CULTIVATED ON POLYMERIC SCAFFOLDS
Stem cells; Polylactic acid; Low-level laser; Cell proliferation
Photobiomodulation with low-level laser therapy (LLLT) can stimulate the proliferation of various cell types, including stem cells. Stem cells from human exfoliated deciduous teeth (SHEDs) multiply and differentiate faster than the other mesenchymal stem cells, being the target of several studies in the field of tissue engineering. For the cells to proliferate and differentiate in vitro, a favorable microenvironment needs to be provided and the use of a biomaterial is a viable alternative. Polylactic acid (PLA) is distinguished for this purpose by its biocompatibility and biodegradability properties, as well as the low cost. The objective of this study is to evaluate the influence of different photobiomodulation protocols on the proliferation and viability of SHEDs cultured on two-dimensional PLA scaffolds. The cells will be irradiated with diode laser (InGaAlP, wavelength 660 nm) using four protocols: (I) - power of 30mW and dose of 1 J/cm²; (II) - power of 15mW and dose of 1 J/cm²; III; power of 30mW and dose of 4 J/cm²; and IV: power of 15 mW and dose of 4 J/cm². Cell viability and proliferation will be assessed at intervals of 24, 48, and 72 hours, using the Trypan blue, Alamar Blue, MTT, and Live/Dead assays. Cellular morphology will be evaluated by SEM at 72 h. Quantitative data will be submitted to non-parametric statistical tests, with 5% significance level.