OR01 - The Antibacterial Effects of Hydraulic Obturation on Intracanal Bacteria

Abstract: Single versus multiple-visit non-surgical endodontic treatment has historically been a controversial subject among clinicians and remains an empirical choice by providers. Recent advances in endodontics include single-visit treatment with a bioceramic sealer-based hydraulic obturation technique. In theory, this technique may provide enhanced antibacterial effects over traditional gutta-percha-based obturation methods, but this had yet to be tested. We used an ex vivo tooth model to test the central hypothesis that hydraulic obturation using bioceramic sealer (BC sealer) exerts an antibacterial effect similar to calcium hydroxide as an intracanal medicament and superior to gutta-percha-based obturation. A dual-species biofilm model consisting of Enterococcus faecalis and Streptococcus mutans was first established on the root surfaces of single-rooted extracted human teeth. The experimental groups were sealer-based (hydraulic) obturation with BC sealer, gutta-percha-based obturation with BC sealer, and gutta-percha-based obturation with AH plus. A saline group and a calcium hydroxide group served as negative and positive controls, respectively. Bactericidal effects were determined using LIVE/DEAD assays with confocal microscopy (n=3 roots/group). Bacteriostatic effects were determined by testing the ability of the remaining bacteria to form colonies and the XTT assay (n=6 roots/group). Data were analyzed by 2-factor ANOVA. Our results show that hydraulic obturation using BC sealer has superior antibacterial effects compared to intracanal Ca(OH)2 medication and gutta-percha-based obturation with AH plus (p < .05).