title: Combined effect of a mixture of tetracycline, acid, and detergent, and nisin against Enterococcus faecalis and Actinomyces viscosus biofilms.
abstract: OBJECTIVE
  To evaluate the combined effect of a mixture of tetracycline, acid, and detergent (MTAD) and Nisin against Enterococcus faecalis (E. faecalis) and Actinomyces viscosus (A. viscosus) biofilms.
  
  
  METHODS
  This study was conducted between June and December 2013 in collaboration with Dental Caries Research Chair, College of Dentistry, King Saud University, Riyadh, Saudi Arabia. Single-species biofilms (n=9/species/observation period) were generated on membrane filter discs and subjected to 5, 10, or 15 minute incubation with MTADN (MTAD with 3% Nisin), 5.25% sodium hypochlorite (NaOCl), or normal saline. The colony forming units were counted using the Dark field colony counter.
  
  
  RESULTS
  A 100% bactericidal effect of 5.25% NaOCl was noted during the 3 observation periods; a significant reduction (p=0.000) in mean survival rates of E. faecalis (77.3+13.6) and A. viscosus (39.6+12.6) was noted after 5 minutes exposure to MTADN compared with normal saline (78000000+5291503) declining to almost no growth after 10 and 15 minutes. The survival rates of the E. faecalis and A. viscosus biofilm were no different after treatment with MTADN and 5.25% NaOCl at the 3 observation periods (p=1.000).
  
  
  CONCLUSIONS
  A combination of MTAD and Nisin was as effective as NaOCl against E. faecalis and A. viscosus biofilms.
authors.affiliation: Department of Restorative Dental Science, College of Dentistry, King Saud University, PO Box 62645, Riyadh 11595, Kingdom of Saudi Arabia. E-mail. h_balto@yahoo.com.
authors.forename: Hanan A
authors.initials: HA
authors.lastname: Balto
authors.forename: Zahid A
authors.initials: ZA
authors.lastname: Shakoor
authors.forename: Maha A
authors.initials: MA
authors.lastname: Kanfar
mesh_terms: D000143:Acids / Q000008:administration & dosage / Q000494:pharmacology*; D000190:Actinomyces / Q000187:drug effects*; D018441:Biofilms / Q000187:drug effects*; D003902:Detergents / Q000008:administration & dosage / Q000494:pharmacology*; D013293:Enterococcus faecalis / Q000187:drug effects*; D009561:Nisin / Q000008:administration & dosage / Q000494:pharmacology*; D013752:Tetracycline / Q000008:administration & dosage / Q000494:pharmacology*; D014783:Viscosity
chemical_list: D000143:Acids; D003902:Detergents; D009561:Nisin; D013752:Tetracycline