The use of photobiomodulation therapy or LED and mineral trioxide aggregate improves the repair of complete tibial fractures treated with wire osteosynthesis in rodents

The repair of large bone defects is lengthy and complex. Both biomaterials and phototherapy have been used to improve bone repair. We aimed to describe histologically the repair of tibial fractures treated by wiring (W), irradiated or not, with laser (lambda 780 nm, 70 mW, CW, spot area of 0.5 cm(2), 20.4 J/cm(2)(4 x 5.1 J/cm(2), Twin Flex Evolution (R), MM Optics, Sao Carlos, SP, Brazil) per session, 300 s, 142.8 J/cm(2)per treatment) or LED (lambda 850 +/- 10 nm, 150 mW, spot area of 0.5 cm(2), 20.4 J/cm(2)per session, 64 s, 142.8 J/cm(2)per treatment, Fisioled (R)(MM)-M-, Optics, Sao Carlos, Sao Paulo, Brazil) and associated or not to the use of mineral trioxide aggregate (MTA, Angelus (R), Londrina, PR, Brazil). Inflammation was discrete on groups W and W + LEDPT and absent on the others. Phototherapy protocols started immediately before suturing and repeated at every other day for 15 days. Collagen deposition intense on groups W + LEDPT, W + BIO-MTA + LaserPT and W + BIO-MTA + LEDPT and discrete or moderate on the other groups. Reabsorption was discrete on groups W and W + LEDPT and absent on the other groups. Neoformation varied greatly between groups. Most groups were partial and moderately filed with new-formed bone (W, W + LaserPT, W + LEDPT, W + BIO-MTA + LEDPT). On groups W + BIO-MTA and W + BIO-MTA + LaserPT bone, neoformation was intense and complete. Our results are indicative that the association of MTA and PBMT (lambda = 780 nm) improves the repair of complete tibial fracture treated with wire osteosynthesis in a rodent model more efficiently than LED (lambda = 850 +/- 10 nm).

Automated summary

The experimental results of treating complete tibial fractures with different phototherapy protocols indicate that the combination of MTA and laser therapy is more effective than LED therapy.