Could the sealer thickness affect the filling ability of bioceramic endodontic materials? Evaluation in a simulated physiological condition

Context: Bioceramic sealers must provide filling and dimensional stability over time. Aims: To evaluate by micro-computed tomography (micro-CT), the effect of sealer thickness on the physical properties of Bio-C Sealer (BCS) and BioRoot RCS (BR) after immersion in phosphate-buffered saline (PBS) for 7 and 30 days. Materials and Methods: Extracted bovine teeth were prepared with ProDesign Logic 40/0.05, and the last 4-mm apical of the roots was sectioned. Then, the specimens were filled using the single-cone technique with BCS or BR (<i>n</i> = 8), providing a smaller sealer thickness (ST) of the apical third and a greater sealer thickness (GT) of the cervical third. The samples were immersed in PBS for 7 and 30 days. After scanning by micro-CT, the volumetric change, material/dentin interface, and filling capacity were assessed. Statistical Analysis Used: ANOVA/Tukey, paired, and unpaired t-tests were performed (α =0.05). Results: Sealer thickness did not influence the filling capacity in all conditions tested. After 7 days, BR had a higher volume loss than BCS, with no influence of the sealer thickness. The volumetric loss and percentage of interface gaps were higher for both sealers with GT from 7 to 30 days of immersion. BR with GT showed a higher presence of interface gaps compared to the other groups in all the experimental periods. Conclusions: GT negatively influences the volumetric change and presence of gaps in the material/dentin interface, especially for BR. Both materials demonstrate adequate filling ability regardless of the sealer thickness used.