Abstract
Fibroblasts are essential in the wound healing process due to their deposition of collagen, and secretion of growth factors. Many studies have proposed that there is a
proliferation of these cells after light exposure. Pereira et al. investigated the ability
of a Ga-AS diode pulsed laser at 904 nm on cell growth and procollagen synthesis of
cultured fibroblasts. The results obtained showed that at smaller doses of 3 and
4 J=cm2, there was significant increase in the cell numbers compared to higher doses,
but there was no effect on procollagen synthesis at any of these energy densities. This
leads to the conclusion that cellular proliferation is enhanced by lasers at specific
parameters, but procollagen synthesis may need another specific combination of
parameters to appreciate production in collagen (15). In the work of Almeida-Lopes
et al., their study compared the effect of fibroblasts on a range of wavelengths (670786 nm) at a fixed dose of 2 J=cm2. The results from this study had similar findings to
the previous study in that low level laser therapy can increase the rate of proliferation. This investigation also illustrated that culture mediums only supplemented by
5% fetal bovine serum without any other nutritional benefits had significant cell
growth compared to ideal medium supplemented with 10% fetal bovine serum. This
demonstrates that lasers can improve cellular functions either by increasing the
amount of growth factors or other cellular mediators in stressful conditions (16).