Comparison of the quality of the canal fillings performed using bioceramic and resin-based root canal sealers and the bond strength of the sealers

For a successful root canal treatment, the canal system should be filled as three dimensional without any leakage in order to preserve the level of disinfection achieved after the process of shaping and irrigation of the root canal system and to prevent the passage of bacteria through the canal. A better leak-proof seal can be provided by preventing the formation of voids in the root canal by means of bonding sealers canals to dentin and gutta-perka. In this study, it was aimed to compare the presence of void space in canals filled with the method of lateral condensation by using newly developed bioceramic canal sealers and resin-based canal sealers frequently used clinically by micro-CT and to evaluate the adhesion of canal sealers to dentin by push-out test. In the study, 64 extracted, single rooted and single canal human mandibular premolars were used. All teeth were shaped by using the Protaper Universal rotary files. The teeth were divided into 4 groups, each containing 16 teeth. Root canals were filled with AH plus, MM seal, Endosequence BC sealer and BioRoot RCS canal sealers by using cold lateral condensation method. Teeth having filled canals were scanned in high-resolution micro-CT and the space volumes in the canals were calculated. In the second phase of the study, teeth were embedded in the acrylic resin by using roller molds. After that, sections of 1mm thickness were taken from the teeth. Instron device was used for the measurement of bond strength of canal sealers to dentin. The push-out force was applied until the failure occurred in the joint of the canal filling to the dentin and the values obtained were recorded. The data were analyzed in PC using SPSS 25.0 (Statistical Packages of Social Sciences) program. As a result, none of the used root canal sealers provide a void-free canal filling. When all groups were evaluated within themselves, it has been observed that the void space volume in the apical third was less than the volume in coronal and middle thirds. While there was no statistically significant difference in the volume of the voids found in the entire root among the canal sealers which were used (p> 0,05), the highest void volume in the entire root was found in the MM Seal group (1.81%) and the least void volume was found in Endosequence BC sealer group (1,11%).The lowest values of bond strength were found statistically significant in the MM Seal group. There was no statistically significant difference among the bond strength values of AH Plus, Endosequence BC Sealer and BioRoot RCS canal sealer.