Latent forms of the carious lesion of human lower third molars

Abstract

The most pronounced thinning of the enamel is in the intercuspal fissures of the third molars, which are characterized by a wide variety of shapes and sizes up to the abnormal disruption of their development and teething, which often causes all kinds of clinical complications. The aim: The purpose of the paper was to obtain the data on the structural state of the third molars and identify their most damaged areas in the latent form of dental caries. Materials and Methods: 10 lower third molars with an intact crown without clear external signs of tooth decay have been examined. The teeth were embedded into epoxy resin, using the “Himkontakt-Epoxy” glue. Upon the completion of full polymerization, the resulting epoxy blocks were cut by the separation disk. Afterwards, the cross-cut ends with the naked tooth tissues were grinded and polished to obtain even unscratched slice, which was subsequently etched in Trilon-B (disodium salt EDTA) with the follow up staining in 1% borax methylene blue solution. Epoxy tooth slices were studied with the light optics in the reflected light using the MBS-9 binocular loupe, equipped with a digital camera adapter. Results: The process of tooth decay is of endogenous origin. The specimen of the third lower molar shows all pathomorphological signs of the latent carious lesions. Impacted lower third molar with deep carious was detected. It is obvious that, being in the subcortical zone of the alveolar ridge of the lower jaw, this abnormally developed tooth could not be exposed to any external effects. Conclusions: The microscopic study of the tooth, found in the ovarian dermoid cysts, showed that it was affected by caries that completely excludes the exogenous factors in its origination. We hypothesize that the mechanism of tooth decay directly involves the immune responses, antigens of which are (in certain circumstances) proteins of the dentin and enamel. This is the rationale for introduction into the current nosology the term “carious disease” instead of “dental caries”.