This study aimed to assess the repair of complete surgical
tibial fractures fixed with internal rigid fixation (IRF) associated or not to the use of
mineral trioxide aggregate (
MTA) cement and treated or not with
laser (λ = 780 nm, infrared) or LED (λ = 850 ± 10 nm, infrared) lights, 142.8 J/cm2 per treatment, by means of Raman spectroscopy. Open surgical
tibial fractures were created on 18 rabbits (6 groups of 3 animals per group, ∼8 months old) and fractures were fixed with IRF. Three groups were grafted with
MTA. The groups of IRF and IRF + MTA that received
laser or LED were irradiated every other day during 15 days. Animals were sacrificed after 30 days, being the tibia surgically removed. Raman spectra were collected via the probe at the defect site in five points, resulting in 15 spectra per group (90 spectra in the dataset). Spectra were collected at the same day to avoid changes in
laser power and experimental setup. The ANOVA general linear model showed that the
laser irradiation of tibial
bone fractures fixed with IRF and grafted with
MTA had significant influence in the content of
phosphate (peak ∼960 cm-1) and carbonated (peak ∼1,070 cm-1)
hydroxyapatites as well as
collagen (peak 1,452 cm-1). Also, peaks of
calcium carbonate (1,088 cm-1) were found in the groups grafted with
MTA. Based on the Raman spectroscopic data collected in this study,
MTA has been shown to improve the repair of complete
tibial fractures treated with IRF, with an evident increase of
collagen matrix synthesis, and development of a scaffold of
hydroxyapatite-like
calcium carbonate with subsequent deposition of
phosphate hydroxyapatite.