title: Comparative analysis of the antibacterial effects of combined mouthrinses on Streptococcus mutans.
abstract: OBJECTIVE
  Chlorhexidine has been proposed as a potent chemotherapeutic agent against oral bacteria. However, there are some inconsistent results regarding the usefulness of chlorhexidine mouthrinse as an antimicrobial for Streptococcus mutans. The purpose of this study was to investigate the effectiveness of combining oral rinses to reduce S. mutans levels in human saliva.
  
  
  METHODS
  Sixteen healthy adult subjects were randomly assigned to one of four rinse groups using a 4-cell crossover design. The groups rinsed twice a day for 7 days with one of the following: 0.12% chlorhexidine (PerioGard), 1.5% hydrogen peroxide (Peroxyl), a combined chlorhexidine+hydrogen peroxide, or water (control). Every 5 weeks, each group initiated a different rinse. Saline wash samples were collected on days 7 and 21 for assessment of S. mutans and total streptococci.
  
  
  RESULTS
  No significant differences were seen in S. mutans levels among the groups; however, the levels of total streptococci on day 7 samples were significantly lower in the chlorhexidine and chlorhexidine+hydrogen peroxide groups than in the hydrogen peroxide and control groups. There was no additional decrease seen in S. mutans or total streptococci levels in the group receiving chlorhexidine+hydrogen peroxide compared to chlorhexidine alone.
  
  
  CONCLUSIONS
  Sample variation was high throughout the study, with a significant trend toward lower counts as the study progressed. Adding hydrogen peroxide to the chlorhexidine mouthrinse did not result in a further decrease in S. mutans levels.
authors.affiliation: Department of Pediatric Dentistry, University of Alabama at Birmingham, Birmingham, AL 35294-0007, USA.
authors.forename: A
authors.initials: A
authors.lastname: Menendez
authors.forename: F
authors.initials: F
authors.lastname: Li
authors.forename: S M
authors.initials: SM
authors.lastname: Michalek
authors.forename: K
authors.initials: K
authors.lastname: Kirk
authors.forename: S K
authors.initials: SK
authors.lastname: Makhija
authors.forename: N K
authors.initials: NK
authors.lastname: Childers
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D000900:Anti-Bacterial Agents / Q000008:administration & dosage*; D002710:Chlorhexidine / Q000008:administration & dosage*; D004359:Drug Therapy, Combination; D006801:Humans; D006861:Hydrogen Peroxide / Q000008:administration & dosage*; D008875:Middle Aged; D009067:Mouthwashes / Q000008:administration & dosage*; D012463:Saliva / Q000382:microbiology; D013295:Streptococcus mutans / Q000187:drug effects*; D013997:Time Factors
chemical_list: D000900:Anti-Bacterial Agents; D009067:Mouthwashes; D006861:Hydrogen Peroxide; D002710:Chlorhexidine