title: Antimicrobial effects of the combination of chlorhexidine and xylitol.
abstract: OBJECTIVE
  To assess the effect of combining 1% chlorhexidine varnish (CHX) with xylitol chewing gum (XYL) on Streptococcus mutans and biofilm levels in 6-8-year-old children.
  
  
  METHODS
  Randomised controlled study.
  
  
  METHODS
  Eighty-two 6-8-year-old children were randomly divided into groups as follows: G1 (n = 20): xylitol chewing gum twice a day after breakfast and lunch; G2 (n = 20): xylitol gum as G1 plus chlorhexidine varnish application at the start of the study and after one and two months; G3 (n = 20): chlorhexidine varnish as G2; and G4 (n = 22): fluoride gel application at the start of the study and after one and two months. Microbiological tests were performed to assess Streptococcus mutans colony forming units (CFU) and the teeth of those children with moderate or higher CFU scores were examined for visible biofilm. CFU scores were categorised as follows: 0 = absence of S. mutans, 1 = low level (1-10 CFU), 2 = moderate level (11-100 CFU), 3 = high level (101-250 CFU), 4 = very high level (>250 CFU). Biofilm scores based on a scale from 0 (absence of biofilm) to 5 (thick biofilm firmly adhered to posterior and anterior teeth) were obtained.
  
  
  RESULTS
  The biofilm reduction was greater in G2 and G3, with mean values of 3.38 and 3.17 to 1.79 and 1.88, respectively (p <0.05). All groups presented a reduction in the S. mutans levels. XYL + CHX showed the largest reduction throughout the study period, with 58.3% in the first month, 84.2% in the second and 92.9% at the end of the study.
  
  
  CONCLUSIONS
  The XYL + CHX combination was efficient and superior to single treatments in controlling biofilm and suppressing S. mutans.
authors.affiliation: Department of Pediatric Dentistry and Orthodontics, School of Dentistry, Federal University of Rio de Janeiro, Brazil. vicancio@ig.com.br
authors.forename: V A C
authors.initials: VA
authors.lastname: Paula
authors.forename: A
authors.initials: A
authors.lastname: Modesto
authors.forename: K R N
authors.initials: KR
authors.lastname: Santos
authors.forename: R
authors.initials: R
authors.lastname: Gleiser
mesh_terms: D000149:Acidulated Phosphate Fluoride / Q000627:therapeutic use; D000891:Anti-Infective Agents, Local / Q000008:administration & dosage / Q000627:therapeutic use*; D058491:Bacterial Load; D018441:Biofilms / Q000187:drug effects*; D002327:Cariostatic Agents / Q000627:therapeutic use*; D002638:Chewing Gum; D002648:Child; D002710:Chlorhexidine / Q000008:administration & dosage / Q000627:therapeutic use*; D003773:Dental Plaque / Q000382:microbiology; D004338:Drug Combinations; D005260:Female; D005460:Fluorides, Topical / Q000627:therapeutic use; D005500:Follow-Up Studies; D005782:Gels; D006801:Humans; D008297:Male; D012463:Saliva / Q000382:microbiology; D013295:Streptococcus mutans / Q000187:drug effects*; D013549:Sweetening Agents / Q000627:therapeutic use*; D013943:Thymol / Q000008:administration & dosage / Q000627:therapeutic use; D014070:Tooth / Q000382:microbiology; D014993:Xylitol / Q000627:therapeutic use*
chemical_list: D000891:Anti-Infective Agents, Local; D002327:Cariostatic Agents; D002638:Chewing Gum; D004338:Drug Combinations; D005460:Fluorides, Topical; D005782:Gels; D013549:Sweetening Agents; C079161:chlorhexidine, thymol drug combination; D000149:Acidulated Phosphate Fluoride; D013943:Thymol; D002710:Chlorhexidine; D014993:Xylitol