Infrared microspectroscopy characterization of gingival crevicular fluid during orthodontic treatment

Abstract

The gingival crevicular fluid (GCF) is a site-specific exudate deriving from the epithelium lining of the gingival sulcus. GCF analysis provides a simple and noninvasive diagnostic procedure to follow-up the periodontal ligament and bone remodeling in response to diseases or mechanical stimuli as the orthodontic tooth movement. The aim of this study was to use infrared (IR) microspectroscopy to assess GCF composition changes at different phases of fixed orthodontic treatment. GCF samples were collected using sterile paper cones from young patients before starting the orthodontic treatment (control) and after 2, 7 and 14 days of fixed orthodontic treatment. Infrared spectra were obtained on GCF extracted from cones. In these spectra, the contributions of main functional groups and the changes related to the different phases of orthodontic treatment were present. Different normalizations to significant peaks were performed to better evidence the changes occurring at different times of the orthodontic treatment. Useful information was also obtained by evaluating the ratio between the areas of selected bands related to protein, lipid and carbohydrate contents. The results here reported show that IR microspectroscopy analysis can give an important contribution for monitoring GCF changes during the early phases of the orthodontic tooth movement.