Examination of human gum biopsy layers using Raman spectroscopy

Abstract

An urgent task in modern dentistry is the restoration of defects and deficiencies in the oral mucosa with proprietary gum autografts. Evaluation of the quality and suitability of gum autografts for transplantation is carried out only by visual means, or by histological methods, which are time-consuming and invasive research methods. Currently, there are many optical methods that are widely used in biomedical tasks. One of the widely used methods in dental tasks is Raman spectroscopy. Therefore, the aim of the work was to study the layers of human gum biopsies using Raman spectroscopy. This method was implemented using a specialized experimental stand, which includes a Shamrock SR303i spectrograph with an integrated digital camera cooled to −60°C, a PBL785 optical Raman module and a computer.
Materials and methods.
The research materials were human gums obtained by mucotomy in 7 patients. The resulting material was conditionally divided into 3 groups: keratinized (keratinized) layer, epithelial layer, connective tissue layer. Further processing of the obtained Raman spectra included autofluorescence filtering by subtracting the fluorescent component by polynomial approximation with a polynomial degree of 11, as well as statistical data processing using linear discriminant analysis.
Results.
Spectral features of the studied layers of human gum biopsies were established, which are manifested in a decrease in the intensity of Raman lines corresponding to the contribution of proteins and lipids and showing the maturity of the keratinized oral mucosa. There is also an increase in Raman scattering lines, which correspond to cellular components and are associated with the formation of keratin filaments in the cells of the keratinizing layer. In the course of the experiments, it was shown that spectroscopic Raman analysis allows for an express assessment of the regenerative potential of an autobioptate in the restoration of oral mucosa defects.