Effectiveness of intracanal dressing protocols on Enterococcus faecalis biofilm in a bovine teeth model – an in vitro study

  • Maristela Gutierrez de Borba Pontifical University Catholic of Rio Grande do Sul
  • Matheus Albino Souza Pontifical University Catholic of Rio Grande do Sul
  • Fabiana Vieira Vier-Pelisser Pontifical University Catholic of Rio Grande do Sul
  • Alexandre Correa Ghisi Pontifical University Catholic of Rio Grande do Sul
  • Jéssia Stephanie Rodrigues Nasário Pontifical University Catholic of Rio Grande do Sul
  • Silvia Dias de Oliveira Pontifical University Catholic of Rio Grande do Sul
  • José Antônio Poli de Figueiredo Pontifical University Catholic of Rio Grande do Sul
Keywords: Biofilm, Enterococcus faecalis, Bovine teeth, Intracanal dressing


Aim: The purpose of study was to evaluate, in vitro, the effectiveness of intracanal dressing protocols in root canals infected with E.faecalis. 
Methods: Eighty eight bovine incisors were contaminated with E. faecalis, remaining in culture for 30 days for biofilm formation. The teeth were divided into ten groups according to presence of disinfectant penetration (DP), intracanal dressing and medication placement site: G1 (CHX gel) – 2% chlorhexidine (CHX) gel (cervical third), G2 (CHX liq) – 2% CHX liquid (cervical third), G3 (TC) – tricresol formalin (canal entrance). In these groups (n=10), DP was not performed. G4 (DP+CHX gel) – 2% CHX gel (all thirds), G5 (DP+CHX liq) – 2% CHX liquid (all thirds), G6 (DP+TC) – tricresol formalin (canal entrance), G7 (DP+Ca(OH)2) – calcium hydroxide paste (all thirds). In these groups (n=10) DP with 2% NaOCl was performed. Groups G8 (DP NaOCl) – DP with 2% NaOCl, G9 (DP H2O) – DP with distilled water, and G10 – (no treatment) were considered controls (n=6). Microbiological test (CFUs counting) and scanning electron microscopy (SEM) were performed to evaluate and illustrate respectively the effectiveness of proposed treatments.
Results: Microbiological test demonstrated that groups G4 (DP+CHX gel), G5 (DP+CHX liq), G6 (DP+TC) and G7 (DP+Ca(OH)2) showed no bacterial growth, being statistically different from all other groups (p<0.05).
Conclusion: 2% chlorhexidine gel, 2% chlorhexidine liquid and calcium hydroxide paste in all root canal thirds, as well as tricresol formalin on root canal entrance, are effective intracanal dressings against E. faecalis, when associated to previous DP with 2% NaOCl.


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Original Article