Biocorrosive behavior of sulphate-reducing bacteria in kerr endodontic files: Determination of the corrosion
Fabiano Luiz Heggendorn1, Luiz André Lucas Teixeira Pinto2, Lucio Souza Gonçalves3, Viviane de Oliveira Freitas Lione4, Walter Barreiro Cravo Junior2, Marcia Teresa Soares Lutterbach2
1 Department of Corrosion and Degradation, Laboratory of Biocorrosion and Biodegradation, National Institute of Technology; Department of Drugs and Medicine, Laboratory of Pharmaceutical Bioassays, School of Pharmacy, Fluminense Federal University, Rio de Janeiro, Brazil
2 Department of Corrosion and Degradation, Laboratory of Biocorrosion and Biodegradation, National Institute of Technology, Rio de Janeiro, Brazil
3 Post-Graduate Program in Dentistry, Faculty of Dentistry, Estacio de Sa University, Rio de Janeiro, Brazil
4 Department of Drugs and Medicine, Laboratory of Pharmaceutical Bioassays, School of Pharmacy, Fluminense Federal University, Rio de Janeiro, Brazil
Dr. Fabiano Luiz Heggendorn
Rua Feliz da Cunha 11, Ap. 806, Tijuca, CEP 20260-300, Rio de Janeiro
Source of Support: None, Conflict of Interest: None
Aims: This study determined the corrosion rate by mass loss caused by oral strains of sulphate-reducing bacteria (SRB) in Kerr endodontic files (KF), aiming the development of a biopharmaceutical that facilitates the removal of endodontic limb fragments from root canals.
Materials and Methods: Nine new KF were analyzed after immersion in the modified Postgate E culture medium inoculated with Desulfovibrio desulfuricans oral (84 days), Desulfovibrio fairfieldensis in the consortium (84 days) and environmental D. desulfuricans (119 days).
Results: Optical microscopy revealed corrosion suggestive areas in all files submitted to immersion in SRB cultures, presenting a statistical difference (P < 0.05) between the samples environmental D. desulfuricans and KF control and between oral D. desulfuricans and KF control. Epifluorescence microscopy revealed an active SRB biofilm over the entire metal surface of the KF, as evidenced by the SYTO® 9 fluorophore.
Conclusion: SRB were capable of promoting biocorrosion in Kerr type endodontic files, but with low rate.