Introduction. Due to complications in prosthetics with non-removable dentures, orthopedic treatment of teeth and dentition defects requires further improvement of non-removable prostheses’ design and methods of preparation of supporting teeth. In this regard, the issues of theoretical validation of teeth preparations methods for metal-ceramic dentures make the study relevant and appropriate.  Aim of the study. To study the condition of dental tissues, resulting from traditional methods of preparation for cermet structures. The morphological changes in the teeth tissues should be expanded based on the outcomes.   Materials and methods. The material of the study served premolars, initially pre-prepared by creating a classical ledge and its symbol, covered with cermet crowns, and accordingly, divided into two groups. Thick and thin sections of these teeth were made and histochemical marking ShIK-alcian blue and hematoxylin-eosin was carried out.  Results. In the first group, significant blood flow disorders occured in the pulp immediately after the cermet structure was fixed onto the pre-prepared premolar with a ledge in the cervical region, some of which are irreversible in the form of hemorrhages and sludge eradication in the venules. In the second group, less significant circulatory disorders are noted in the form of stasis of capillaries and edema of connective tissue, while preserving the enamel in the cervical region with odontopreparation of premolars without a ledge.  Conclusions. In the first group, irreversible changes occured in the pulp, causing disturbances in neurotrophic processes in the pulp and initiate inflammatory processes. Vibration fluctuations during preparation in the tooth’s neck region disorganize dentin leading to development of local angioedema disorders of the pulp. The results obtained in the second group initiate disorganization of the dentin without extension to the lateral and root parts of the dentin, while bearing a reversible character. Based on the above, the results of our research allow us to propose to preserve the odontopreparation for cermet structures to the cervical part, creating a symbol of the ledge.