AN EFFECT OF APICAL PREPARATION ON THE QUALITY OF ENDODONTIC TREATMENT

Relevance: The apical third of the root canal is difficult to access for high-quality endodontic treatment due to the complex anatomical and morphological structure of this area, which includes anastomoses, extra canals, apical deltas, various shapes of the apical foramen. Based on this, the accomplishment of suitable mechanical preparation of the apical part of the root canal remains one of the most complex and important tasks for successful endodontic treatment. Aim: to evaluate the impact of mechanical preparation of the lower third of the root canal on the quality of endodontic treatment. Materials and methods: 30 extracted teeth (incisors, premolars, molars), which root canals had been mechanical and medicamentous processing, were examined. All teeth were divided into two groups based on the extent of apical preparation: up to №25 and №50 according to ISO. The root canal obturation was done with the technique of vertical condensation of gutta-percha. The X-ray diagnostics was used to control the quality of obturation. Teeth from each group that met the inclusion criteria were placed in a solution of methylene blue. Then, transversal cuts were received with a separation disc. The degree of dye penetration into the dentin of the root canal was recorded on these cuts. Results: The study results demonstrated that the adhesion of the filling material to the walls of the root canal was significantly worse in the first group of teeth (apical enlargement up to 25/04), compared to the second group (apical enlargement to 50/04). Conclusion: The root canal enlargement only to №25 according to ISO is not enough for the complete removal of contaminated dentin and the accomplishment of high-quality obturation. The suitable mechanical preparation of the apical part with large sizes allows do more thorough irrigation of the root canal and subsequent obturation, which is a keystone for successful endodontic treatment.