Assessment of changes in mineral components in bone repair after laser therapy and pharmacotherapy by μ-EDX: a new potential tool in medical diagnostics.

Background Data: Energy-dispersive microspectroscopy X-ray fluorescence (μ-EDX) is a non-destructive, multi-element analytical method. This technique is able to quickly perform a qualitative and semiquantitative evaluation of several sorts of samples with minimal or no previous sample preparation. Low-level laser therapy (LLLT) and synthetic calcitonin have been used to promote osteogenesis and to accelerate the repair process in bone lesions.

Objective: The aim of this study was to evaluate qualitatively and semiquantitatively biochemical changes in the composition of the bone tissue during the repair process in rats by the analytical measurement tool, μ-EDX.

Methods: We created a surgical bone defect in 60 Wistar rats with induced osteoporosis treated with calcitonin, LLLT, and a combination of both. The animals were divided into four groups. In groups Ca and CaLa, calcitonin, 2 UI/kg, i.m., was administered on alternate days. LLLT (20 J/cm(2), 10 mW, 830 nm, 6 sec, every 48 hours) was applied to the La and CaLa groups. The experimental times were 7, 14, and 21 days. After euthanasia, the specimens were measured for inorganic chemical compounds with μ-EDX.

Results And Conclusions: This study showed that it was possible to perform qualitative and semiquantitative analysis of inorganic components of biological samples with this technique during the bone repair process using different experimental treatment protocols. CaLa specimens showed the relation between calcium and phosphorus (Ca/P) closest to stoichiometric hydroxyapatite.