Photobiomodulation on critical bone defects of rat calvaria: a systematic review

Bone defects following trauma represent a high impact on the quality of life of millions of people around the world. The aim of this study was to review photobiomodulation (PBM) action in the treatment of bone critical defects in rat calvaria, related to evaluation of the current protocols applied. One hundred and forty-seven articles related to the subject were found by searching the main databases (Pubmed, Lilacs, Web of Science, and Scopus) considering the period of publication until the year 2017, and only 14 corresponded the inclusion criteria established for this systematic review. The main parameters of the PBM were expressed in Table 1 . In addition, it was possible to observe the use of two different wavelengths (red and infrared), which are considered therapeutic. Most of the evaluated articles presented positive results that describe a greater amount of neoformed bone, an increase in collagen synthesis, and a contribution to microvascular reestablishment. However, two studies report no effect on the repair process when the PBM was used. In addition, we observed considerable variations between the values of power, fluence, and total energy, which make it difficult to compare the results presented between the selected studies. It was possible to conclude that the infrared laser was more effective in positively stimulating the bone repair process of critical defects. Furthermore, a discrepancy was found in the parameter values used, which made it difficult to choose the best protocol for the treatment of this type of lesion.