EVALUATION OF THE APICAL SEAL AFTER POST SPACE PREPARATION: IN VITRO STUDY

Introduction: Large crown destruction often leads to restoring endodontically treated teeth using post and core. As a result of post space preparation the integrity of the apical seal can be affect, thus increasing the chances of microleakage occurring. Aim: The goal of the study is to observe and evaluate the quality of the apical seal after post space preparation. Materials and Methods: 27 extracted single-rooted teeth-were used. The coronal part was removed, and the root length was standardized to 15mm. The canals were prepared with Revo-S rotary system, irrigated with 5ml 5.25% sodium hypochlorite, saline, and 2ml 40% citric acid. The canals were filled with Adseal and gutta-percha using cold lateral condensation technique. The teeth were divided into two groups depending on post space preparation speed and one control group: first group (n=9) - 2800 rpm; second group (n=10) - 4700 rpm; control group (n=8) - with no preparation. Nail varnish was applied on the external root surface of the teeth except the apical 2mm, afterwards the teeth were insert in 2% methylene blue for 24 hours and then washed under running water for the same time. The teeth were cut longitudinally in a buccal-lingual direction so that the level of dye penetration between the root canal wall and the filling material could be visualized. The measurement was done in mm. Results: The highest average value of apical penetration was observed in the second group (4700 rpm) - 1.10 mm. The difference of the apical penetration between group 2 (1.10 mm) and control group (0.25mm) is significant, while the average value of Group 1 (2800 rpm) does not differ statistically from the other two groups. Concusion: Post space preparation combined with the higher speed of the drill can increase the risk of damage the apical seal.