Antibacterial Effect of Endodontic Disinfections on Enterococcus Faecalis in Dental Root Canals-An In-Vitro Model Study.

Stefan Kranz,Franziska Braeutigam,André Guellmar,Silke Tonndorf-Martini,Markus Reise,Markus Heyder,Bernd Sigusch

doi:10.3390/ma14092427

Stefan Kranz, Franziska Braeutigam + Show 5 more

Open Access

https://doi.org/10.3390/ma14092427

Copy DOI

Abstract

Enterococcus faecalis (E. faecalis) is rather unsusceptible to many root canal disinfections which often cause a therapeutic problem. Therefore, the present in vitro study observed the efficiency of different endodontic antiseptics in their capability to suppress E. faecalis, especially inside dentinal tubules. Prior to any testing, root canals of extracted third human molars were inoculated with E. faecalis for 48 h. Antiseptic dressings with chloramine-T or calcium hydroxide (CaOH) for 24 h or irrigations with 1.3% sodium hypochlorite (NaOCl) were applied with n = 10 in each group. As control irrigation with normal saline was used. All treated canals were manually enlarged from size ISO 50 to 110 and the ablated dentin debris was subjected to microbial culture analysis. Bacterial colonization of the dentinal tubules up to 300 µm was verified by scanning electron microscopy and histological sample preparation. Application of crystalline chloramine-T caused total bacterial suppression inside the dentinal tubules. Dressings with CaOH showed only minor effects. Irrigation with NaOCl caused total eradication of bacteria adhering to the root canal walls, but also failed to completely suppress E. faecalis inside the dentinal tubules. The study showed that chloramine-T is of strong antiseptic activity and also efficient in suppressing E. faecalis inside dentinal tubules.

Highlights

Chemo-mechanical root canal preparation involves the removal of pathogens by mechanical shaping of the root canal walls accompanied by an alternating irrigation with disinfection fluids
The present in vitro study investigated the antibacterial effect of temporary dressings with chloramine-T and calcium hydroxide as well as irrigations with 1.3% sodium hypochloride on E. faecalis inside infected root canals
Prior to any antibacterial testing, colonization of the root canal system by E. faecalis was evaluated by microscopic examination

Summary

Introduction

Chemo-mechanical root canal preparation involves the removal of pathogens by mechanical shaping of the root canal walls accompanied by an alternating irrigation with disinfection fluids. The treatment of infected dental root canals by high quality disinfection is crucial to ensure healing of the apical region and long-term success of an endodontic therapy. In this regard, pathogens that have survived inside dentinal tubules or in inaccessible areas of the root canal system might cause re-infection and treatment failure [1,2]. Pathogens that have survived inside dentinal tubules or in inaccessible areas of the root canal system might cause re-infection and treatment failure [1,2] In those cases, it was shown that in post-treatment endodontic flare-ups besides Streptococci, Lactobacilli, Actinomyces and fungi, the Gram-positive bacterial species Enterococcus faecalis (E. faecalis) is often detected [3,4]. Tetracycline, erythromycin or treatment with Lugol’s iodine solution as well as mineral trioxide aggregate was not efficient in suppressing the species completely [15,16,17]

Methods

Results

Discussion

Conclusion