Changes in the structure of hard tissues of the lower third molars at different stages of eruption according to IR spectroscopy data

The structure of the hard tissues of the lower third molars (enamel, dentin, enamel-dentin junction) at different stages of eruption in the presence/absence of connective tissue dysplasia as a factor that can affect not only odontogenesis, but also teething was analyzed using infrared (IR) spectroscopy. A technique for deconvolution of IR spectra of hard dental tissues has been developed. It has been established that the differences between the stages of eruption are due to changes in the mineral component (phosphate ions) for all dental tissues, while for the enamel-dentin junction an important contribution is made by fluctuations in the methyl and methylene groups of organic compounds, for dentin the contribution of collagen absorption bands is shown. The differences between the stages of tooth eruption increase in the following order: dentin, enamel-dentin junction, enamel. It can be assumed that in the early stages of tooth formation, it is with the participation of collagen proteins that changes in the structure of dentin occur, which subsequently causes changes in the enamel-dentin junction and enamel. Changes in the enamel are subtler and appear only with additional processing of the IR spectra using mathematical methods.