Factors Influencing Apical Extrusion of 2 Types of Endodontic Sealers with Different Delivery Systems

Introduction
Comparison of the apical sealer extrusion of BioRoot RCS and BioRoot Flow and assessment of the influence of procedural and anatomical factors that contribute to extrusion.

Methods
Human mandibular premolars were divided into 2 groups based on apical gauges (<40, >40). Other variables included the presence and size of an apical lesion (2, 4, and 6 mm), canal moisture (dry and wet), pumping and no-pumping action, and sealer tip insertion depth for BioRoot Flow (coronal vs apical). The extruded material was weighed in grams using an analytical balance to the accuracy of 0.0001 g. Statistical analysis included the Kruskal–Wallis test, Mann–Whitney U test, and multivariate linear regression to identify statistically significant factors related to sealer extrusion.

Results
Sealer extrusion was observed in 86.8% of 288 variables tested. BioRoot Flow had significantly higher extrusion across all categorical variables compared to BioRoot RCS (P < .001). Key factors associated with increased extrusion included wet canals (P < .001), larger apical gauge (>40; P < .05), apical sealer placement (P < .005), and pumping action (P < .05). Among all variables, canal moisture was the most consistent contributor to sealer extrusion. The presence of a 6 mm apical lesion combined with an apical gauge of >40 in a wet canal with apically placed BioRoot Flow increased the risk of sealer extrusion.

Conclusions
Wet canals, apical sealer tip placement, larger apical diameters or gauges, and pumping actions significantly increase the risk of extrusion, particularly with sealers that are delivered in a syringe, such as BioRoot Flow. These findings underscore the significance of procedural control in minimizing sealer extrusion and enhancing clinical outcomes.