title: Effect of fluoride varnish and chlorhexidine-thymol varnish on mutans streptococci levels in human dental plaque: a double-blinded randomized controlled trial.
abstract: BACKGROUND
  Recent systematic reviews on clinical trials comparing the efficacy of chlorhexidine and fluoride varnish found that the evidence was inconclusive and further well-conducted randomized controlled clinical trials were advocated.
  
  
  OBJECTIVE
  To compare the effect of fluoride varnish (F) and Chlorhexidine-thymol varnish (CHX/T) with intensive application regimen on mutans streptococci (MS) levels in human dental plaque.
  
  
  METHODS
  Seventy-five subjects between 6 and 10 years of age were allocated into three groups: Group 1-F varnish (n = 29); Group 2-CHX/T varnish(n = 29); Group 3-placebo varnish (n = 17) by stratified block randomization. After baseline plaque samples were obtained, varnish application was applied and repeated at an interval of 3 days in each group. Plaque samples were repeated at 48 h, 1 month, and 3 months. The samples were spread over mitis-salivarius-bacitracin (MSB) culture media, and the colony-forming units per ml (CFU) were measured.
  
  
  RESULTS
  In both Groups 1 and 2, Wilcoxon matched-pairs signed-rank test revealed significant differences in log CFU values of MS between baseline and 48 h, baseline and 1 month but no significant difference between baseline and 3 months. An intergroup comparison at different time intervals showed that the difference between three groups was statistically insignificant.
  
  
  CONCLUSIONS
  F varnish and CHX/T varnish, with an intensive regimen application have equivocal effect on MS levels in dental plaque.
authors.affiliation: Department of Paedodontics and Preventive Dentistry, Manipal College of Dental Sciences, Manipal University, India.
authors.forename: Sanchit
authors.initials: S
authors.lastname: Paul
authors.forename: Suprabha
authors.initials: S
authors.lastname: Baranya Shrikrishna
authors.forename: Ethel
authors.initials: E
authors.lastname: Suman
authors.forename: Ramya
authors.initials: R
authors.lastname: Shenoy
authors.forename: Arathi
authors.initials: A
authors.lastname: Rao
mesh_terms: D002710:Chlorhexidine / Q000737:chemistry*; D003773:Dental Plaque / Q000382:microbiology*; D004311:Double-Blind Method; D005459:Fluorides / Q000008:administration & dosage*; D006801:Humans; D013295:Streptococcus mutans / Q000187:drug effects*
chemical_list: D005459:Fluorides; D002710:Chlorhexidine