In the context of the laser biostimulatory effect on the proliferative and secretory functions of cells, Gabriel found that PBM therapy on surgical oral ulcer in the dorsum of rat tongue, using 660 nm continuous wave diode laser with energy density of 4 J/cm2 applied for 10 consecutive day upregulated expression of NF-κB in keratinocytes on day 3 and downregulated it on day 10 which resulted in increased proliferation of keratinocytes in the early stage and differentiation in the last stages of wound repair [47]. This evidence concerns the gene NFKB1 and Oral ulcer.