Tianfeng Du1, Zhejun Wang2, Ya Shen3, Jingzhi Ma4, Yingguang Cao4, Markus Haapasalo5. 1. Department of Stomatology, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, China; Faculty of Dentistry, Division of Endodontics, Department of Oral Biological and Medical Sciences, University of British Columbia, Canada. 2. Faculty of Dentistry, Division of Endodontics, Department of Oral Biological and Medical Sciences, University of British Columbia, Canada; The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, China. 3. Faculty of Dentistry, Division of Endodontics, Department of Oral Biological and Medical Sciences, University of British Columbia, Canada; Department of Materials Engineering, University of British Columbia, Vancouver, Canada. 4. Department of Stomatology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China. 5. Faculty of Dentistry, Division of Endodontics, Department of Oral Biological and Medical Sciences, University of British Columbia, Canada. Electronic address: markush@dentistry.ubc.ca.
Abstract
INTRODUCTION: The present study aimed to evaluate the antibacterial effect of the combined use of sodium hypochlorite (NaOCl) and root canal sealers on Enterococcus faecalis biofilms using a dentin infection model. METHODS: Cells of E. faecalis were introduced into the dentinal tubules by centrifugation and incubated in brain-heart infusion for 3 weeks. The biofilms in dentin were first subjected to 5% NaOCl or sterile water for 10 minutes followed by an equal thickness of AH Plus (Dentsply International Inc, York, PA), Endosequence BC Sealer (Brasseler USA, Savannah, GA), or MTA Fillapex (Angelus Indústria de Produtos Odontológicos S/A, Londrina, Brazil) placed on the root canal wall of the dentin specimens for 7, 30, and 60 days. Gutta-percha and water were used in a similar manner as controls. The proportions of dead and live bacteria inside the dentinal tubules were assessed by confocal laser scanning microscopy and viability staining. RESULTS: The combined use of NaOCl and sealers (30 and 60 days) killed significantly more bacteria than NaOCl or sealers alone (P < .05). NaOCl + MTA Fillapex was the most effective antibacterial combination by killing 83% bacteria in dentin tubules in 60 days. Thirty and 60 days of exposure to the sealers resulted in significantly more dead bacteria in dentin biofilms than 7-day exposures (P < .05). CONCLUSIONS: The placement of root canal sealer after NaOCl treatment enhanced antibacterial effects against E. faecalis in the dentinal tubules. Little additional effect was obtained after 30 days of exposure to sealers.
INTRODUCTION: The present study aimed to evaluate the antibacterial effect of the combined use of sodium hypochlorite (NaOCl) and root canal sealers on Enterococcus faecalis biofilms using a dentin infection model. METHODS: Cells of E. faecalis were introduced into the dentinal tubules by centrifugation and incubated in brain-heart infusion for 3 weeks. The biofilms in dentin were first subjected to 5% NaOCl or sterile water for 10 minutes followed by an equal thickness of AH Plus (Dentsply International Inc, York, PA), Endosequence BC Sealer (Brasseler USA, Savannah, GA), or MTA Fillapex (Angelus Indústria de Produtos Odontológicos S/A, Londrina, Brazil) placed on the root canal wall of the dentin specimens for 7, 30, and 60 days. Gutta-percha and water were used in a similar manner as controls. The proportions of dead and live bacteria inside the dentinal tubules were assessed by confocal laser scanning microscopy and viability staining. RESULTS: The combined use of NaOCl and sealers (30 and 60 days) killed significantly more bacteria than NaOCl or sealers alone (P < .05). NaOCl + MTA Fillapex was the most effective antibacterial combination by killing 83% bacteria in dentin tubules in 60 days. Thirty and 60 days of exposure to the sealers resulted in significantly more dead bacteria in dentin biofilms than 7-day exposures (P < .05). CONCLUSIONS: The placement of root canal sealer after NaOCl treatment enhanced antibacterial effects against E. faecalis in the dentinal tubules. Little additional effect was obtained after 30 days of exposure to sealers.
Authors: Maria Magana; Christina Sereti; Anastasios Ioannidis; Courtney A Mitchell; Anthony R Ball; Emmanouil Magiorkinis; Stylianos Chatzipanagiotou; Michael R Hamblin; Maria Hadjifrangiskou; George P Tegos Journal: Clin Microbiol Rev Date: 2018-04-04 Impact factor: 26.132