The efficacy of the use of IR laser phototherapy associated to biphasic ceramic graft and guided bone regeneration on surgical fractures treated with miniplates: a Raman spectral study on rabbits

Abstract

The aim of the present study was to assess, by Raman spectroscopy, the repair of surgical fractures fixed with internal rigid fixation (IRF) treated or not with IR laser (λ780 nm, 50 mW, 4 × 4 J/cm(2) = 16 J/cm(2), ϕ = 0.5 cm(2), CW) associated or not to the use of hydroxyapatite and guided bone regeneration (GBR). Surgical tibial fractures were created under general anesthesia on 15 rabbits that were divided into five groups, maintained on individual cages, at day/night cycle, fed with solid laboratory pelted diet and had water ad libitum. The fractures in groups II, III, IV and V were fixed with miniplates. Animals in groups III and V were grafted with hydroxyapatite and GBR technique used. Animals in groups IV and V were irradiated at every other day during 2 weeks (4 × 4 J/cm(2), 16 J/cm(2) = 112 J/cm(2)). Observation time was that of 30 days. After animal death, specimens were taken and kept in liquid nitrogen and used for Raman spectroscopy. Raman spectroscopy showed significant differences between groups (p < 0.001). Basal readings showed mean value of 1,234 ± 220.1. Group internal rigid fixation + biomaterial + laser showed higher readings (3,521 ± 2,670) and group internal rigid fixation + biomaterial the lowest (212.2 ± 119.8). In conclusion, the results of the present investigation are important clinically as spectral analysis of bone component evidenced increased levels of CHA on fractured sites by using the association of laser light to a ceramic graft.

Repair of Surgical Bone Defects Grafted with Hydroxylapatite + β-TCP and Irradiated with λ=850 nm LED Light

“…This has been described in previous studies in which the use of LED was associated with increased proliferation of fibroblasts, chondroblasts and osteoblasts and hence increased deposition of collagen, an important precursor of the mineral matrix deposition (7,8,17). Thus, the increase in bone formation is probably closely linked with both the increased numbers of osteoblasts and their secretory activity.…”

Use of laser fluorescence in dental caries diagnosis: a fluorescence x biomolecular vibrational spectroscopic comparative study

“…Although the mechanism of Raman scattering is different from that of infrared absorption, it provides additional information and its applications include structural and multicomponent qualitative and quantitative analyses. This technique has been used in different areas as a noninvasive diagnostic resource of biological samples, such as periimplant and bone healing, and combination with biomaterials (10)(11)(12).…”

LED phototherapy on midpalatal suture after rapid maxilla expansion: a Raman spectroscopic study

“…Raman spectroscopy used to analyze alterations in both mineral and organic bone components, is considered a gold standard analysis [7]. In this study, Raman spectral analysis indicates that LED phototherapy increased collagen deposition and osteoblastic activity and improved CHA concentration in the midpalatal suture after expansion which could point to an acceleration of bone maturation in the area that is favorable for reducing the retention period and consequently reducing orthodontic treatment time.…”

“…Bone formation acceleration is one of the various biostimulating effects of low level lasers 1 . Laser efficiency in bone healing has been confirmed in various researches [7][8][9] and there's also been reference to accelerating bone neoformation in midpalatal expansion cases 1, [10][11] . Laser irradiation could potentially stimulate the recruitment of osteoblasts and/or their maturation throughout the bone edges of the midpalatal suture in expansion 1 .…”