Elimination of E. faecalis with NaOCl versus chlorhexidine gluconate from primary molar root canal systems: an ex vivo model study

Clin Oral Investig. 2024 Apr 23;28(5):265. doi: 10.1007/s00784-024-05621-6.

Abstract

Objectives: This ex vivo human study aimed to evaluate the efficacy of NaOCl and chlorhexidine gluconate (CHG) irrigations in eliminating Enterococcus faecalis from the RCS of primary molars.

Materials and methods: Disinfected extracted primary molars were inoculated with E. faecalis for 24 h. Then, the RCS samples were then irrigated with either 2.5% NaOCl, 0.2% and 2% CHG, or sham saline. The samples were collected immediately after irrigation; and 24 h later, the bacterial viability and counts were measured using blood agar and qRT-PCR, respectively. Histological sections were used to measure E. faecalis penetration and viability in dentin tubules using fluorescence microscopy.

Results: The recovery of viable E. faecalis after the irrigation of the primary molars showed more significant bactericidal effects of NaOCl and 0.2% and 2% CHG than of saline. Immediately after the irrigation, the NaOCl group showed the greatest reduction in E. faecalis; and 24 h later, all the groups had lower viable E. faecalis than the saline control. The bacterial penetration was also lowest in the NaOCl group, although there was no difference in bacterial viability in the tubules between the groups.

Conclusion: In primary teeth, NaOCl and CHG showed similar degrees of bacterial elimination efficacy in terms of E.faecalis.

Clinical relevance: Within the limitations of this study, NaOCl and CHG have the similar ability to perform endodontic irrigation of primary ex vivo teeth regarding the elimination of E.faecalis, but NaOCl penetrates dentin tubules better.

Keywords: Enterococcus faecalis; Chlorhexidine gluconate; Dental pulp disease; NaOCl; Primary molars; Primary teeth; Root canal treatment.

Publication types

  • Comparative Study

MeSH terms

  • Anti-Infective Agents, Local / pharmacology
  • Chlorhexidine* / analogs & derivatives*
  • Chlorhexidine* / pharmacology
  • Dental Pulp Cavity* / microbiology
  • Enterococcus faecalis* / drug effects
  • Humans
  • In Vitro Techniques
  • Microbial Viability / drug effects
  • Microscopy, Fluorescence
  • Molar* / microbiology
  • Real-Time Polymerase Chain Reaction
  • Root Canal Irrigants* / pharmacology
  • Sodium Hypochlorite* / pharmacology
  • Tooth, Deciduous* / microbiology

Substances

  • Chlorhexidine
  • Sodium Hypochlorite
  • Root Canal Irrigants
  • chlorhexidine gluconate
  • Anti-Infective Agents, Local