MICROSCOPIC CHARACTERISTICS OF STRUCTURAL HETEROGENEITY OF INTACT TOOTH ENAMEL
In violation of the normal course of metabolic processes occurring with the participation of enamel, the features of its structural heterogeneity play an essential role. Detailed morphological microscopic characteristics of these structures are not available in the literature, which led to the need to establish the presence of cavities and microcapillary components in the system of structural heterogeneity of intact tooth enamel between its surface and dentin by using optical inverted and atomic force microscopy. A study of 180 dental preparations was conducted. To study the micro- and ultrastructural structure of enamel, a method for preparing preparations of the longitudinal section of intact tooth enamel, including the final ultrasonic cleaning of the sample, is proposed. A morphological assessment of the structural heterogeneity of intact tooth enamel detected by its optical inverted and atomic force microscopy is given, which can be used in dentistry to develop innovative methods for the diagnosis, treatment and prevention of dental diseases. The revealed inhomogeneities in the structure of the intact tooth enamel tissue are represented by voids (cavities) in the solid phase of the enamel substance, which make it possible to characterize the enamel as a microcapillary-porous system. The solid phase of the enamel and a system of hierarchically organized cavities, extended and interconnected, orderly and evenly distributed over the entire volume of tooth enamel from its surface to the enamel-dentine junction were visualized. The presence of such messages indicates the possibility of direct exchange of substances in the tooth enamel tissue both from the surface and from the root canal. The data obtained by optical inverted and atomic force microscopy give an idea of the presence of hollow spaces - pores conjugated with microcapillaries in the enamel between the surface of the tooth enamel and the border of the enamel-dentine junction, significantly prevailing over the solid phase of the enamel volume. The system of cavities in the tooth enamel can be detected during routine examination using optical inverted and atomic force microscopes, which makes it possible to study objects that do not require significant time and financial costs.