Do laser/LED phototherapies influence the outcome of the repair of surgical bone defects grafted with biphasic synthetic microgranular HA + β-tricalcium phosphate? A Raman spectroscopy study

The treatment of bone loss is difficult. Many techniques are proposed to improve repair, including biomaterials and, recently, phototherapies. This work studied bone mineralization by Raman spectroscopy assessing intensities of Raman peaks of both inorganic (∼960, ∼1,070 cm⁻¹) and organic (∼1,454 cm⁻¹) contents in animal model. Six groups were studied: clot, laser, light-emitting diode (LED), biomaterial (HA + β-tricalcium phosphate), laser + biomaterial, and LED + biomaterial. Defects at right tibia were performed with a drill. When indicated, defects were further irradiated at a 48-h interval during 2 weeks. At the 15th and 30th days, the tibias were withdrawn and analyzed. The ∼960-cm⁻¹ peak was significantly affected by phototherapy on both clot- and biomaterial-filled defects. The ∼1,070-cm⁻¹ peak was affected by both time and the use of the LED light on clot-filled defects. On biomaterial-filled defects, only the use of the laser light significantly influenced the outcome. No significant influence of either the time or the use of the light was detected on clot-filled defects as regards the ∼1,454-cm⁻¹ peak. Raman intensities of both mineral and matrix components indicated that the use of laser and LED phototherapies improved the repair of bone defects grafted or not with biphasic synthetic microgranular HA + β-tricalcium phosphate.