Bone Neoformation Induced by Low-Level Laser and Methylene Blue Suggests Early Ossification in Rats

Introduction: Bone healing depends on inflammation control and tissue repair time. Low-level laser therapy (LLLT) has been investigated to accelerate this process. Methylene blue (MB), together with LLLT, has been investigated for its antioxidant and anti-inflammatory potential; however, the effects of photosensitizers (photodynamic therapy, PDT) are controversial. This study aimed to verify whether the combination of MB and LLLT changes the course of the consolidation of experimental bone defects. Methods: Sixteen Wistar rats underwent femoral bone defects. In the control group (n=4), LLLT simulations were performed without MB. The MB group (n=4) received MB and simulation of LLLT. The LLLT group (n=4) was exposed to LLLT. The PDT+LLLT group (n=4) received MB and LLLT. At the end of 7 or 14 days, the animals were euthanized, and samples were collected.