Comparative evaluation of dentinal tubule penetration of AH plus, bioactive root canal sealer, and an experimental bioactive glass-based bioceramic sealer using confocal laser scanning microscopy: An in vitro study

Abstract

Three-dimensional seal of the root canal improvises the endodontic outcomes. Recent trend has shown influential outcomes with single-cone bioceramic sealers. Hence, the present study aimed to evaluate and compare the dentinal tubule penetration of AH plus, BioRoot root canal sealer (RCS), and an experimental bioactive glass-based bioceramic sealer using confocal laser scanning microscopy (CLSM). A total of 135 extracted human mandibular premolars with single canals were prepared using ProTaper Gold rotary files up to size F3. The samples were randomly divided into three groups ( n = 45 each): Group 1– AH plus, Group 2 – BioRoot RCS, and Group 3 – experimental bioactive glass-based bioceramic sealer. Each sealer was mixed with 0.1% rhodamine B dye to enable fluorescent visualization and applied using the matched-taper single-cone obturation technique. The specimens were stored for 7 days at 37°C in 100% humidity, then sectioned at 2 mm, 5 mm, and 8 mm levels from the apex. The maximum depth of sealer penetration into dentinal tubules was measured using CLSM. The experimental bioactive glass-based bioceramic sealer demonstrated significantly greater dentinal tubule penetration at all three levels compared with BioRoot RCS and AH plus ( P < 0.05). BioRoot RCS showed moderate penetration, whereas AH plus exhibited the least. The apical third displayed the lowest penetration values across all the groups, while the coronal third showed the highest. Incorporation of bioactive glass into a bioceramic sealer significantly enhanced dentinal tubule penetration compared with conventional sealers.