Effects Of CO₂ Laser On Enamel Decalcification Around Orthodontic Brackets

Background: The formation of white spot lesions (WSL) around orthodontic brackets is one of the major risks of fixed orthodontic treatment. However, there is a lack of evidence in the literature on the use of laser treatment for prevention of WSL around orthodontic brackets in fixed orthodontic treatment Objectives: To test the in-vitro effect of carbon dioxide laser therapy on prevention of enamel demineralization around orthodontic brackets. Materials and methods: Fifteen extracted premolar teeth without decay were selected for this experiment and orthodontic brackets were cemented on these teeth with a conventional composite resin. A defined window of 1mm x 3mm next to each side of the bracket was irradiated with 2 sets of laser parameters while the top and bottom windows were selected as the control. A CDC biofilm reactor was used to develop an oral biofilm, simulating intraoral demineralization. Before and after 8 weeks of incubation, mineral content of the experimental and control windows were quantified by a Micro-computed Tomography (ìCT) scanner. A general linear model (GLM) was employed to evaluate the preventive effects of laser therapies and the variation of tooth structure. Results: There was a significant laser effect in preventing enamel demineralization (P<0.001) but no significant difference in mineral loss between the 2 control sites or the 2 laser-treated sites (P>0.05) Qualitative and quantitative assessments with the ìCT revealed a significant heterogeneity of tooth structures. Conclusions: Prevention of demineralization around orthodontic brackets can be achieved by the carbon dioxide laser.