The effects of chlorhexidine gel on Streptococcus mutans infection in 10-month-old infants: a longitudinal, placebo-controlled, double-blind trial.
OBJECTIVE
This study investigated the long-term effects of 0.2% chlorhexidine gel, used as a weekly brush-on gel, on Streptoccocus mutans infection in 10-month-old infants.


METHODS
The investigation followed the criteria of a placebo-controlled, double-blind, longitudinal clinical trial. Infants were recruited at birth and oral microbiological swabs were taken at 3 monthly intervals, together with medical, dental, dietary and brushing histories. Children who were found to be colonized with S. mutans were randomly assigned to either the chlorhexidine-gel group (N = 50) or placebo gel group (N = 46), and parents were instructed to brush the gel on the teeth once per week for 12 weeks. In another control group (N = 210), infants did not use either chlorhexidine or placebo gels. Saliva samples were cultured using S. mutans-selective tryptone-yeast extract-cysteine-sucrose-bacitracin (TYCSB) agar. The mean age of the children was 10.2 +/- 2.6 months at the start of the trial and subjects were followed until the ages of 18 months.


RESULTS
In the children with initial low S. mutans counts of < 300 CFU/mL, there was a significant percentage reduction in S. mutans counts in the chlorhexidine-gel group compared to the placebo gel and no-gel control groups after 3 months of weekly gel brushing. However, no significant differences with the placebo group were observed after 15 months of follow-up. There were 39 children (41%) who achieved reduction of their S. mutans to 0 CFU/mL. Compared to those who remained infected with S. mutans, these children had higher toothbrushing frequencies (P < .001) and toothpaste use (P < .001), as well as lower frequencies of daily feeds (P < .01), and lesser weekly frequencies of sweet solids and liquids (P < .001).


CONCLUSIONS
Children with relatively low initial S. mutans counts (< 300 CFU/mL) showed a reduction in S. mutans counts in the first 3 months when 0.2% chlorhexidine gel was brushed on the teeth weekly. No differences were observed when compared with the placebo and no-treatment groups at later follow-up periods.
Wan
Annetta K L
AK
School of Dentistry, University of Queensland, Brisbane, Australia.
Seow
W Kim
WK
Purdie
D M
DM
Bird
P S
PS
Walsh
L J
LJ
Tudehope
D I
DI
D000891:Anti-Infective Agents, Local / Q000008:administration & dosage*; D002710:Chlorhexidine / Q000008:administration & dosage*; D015169:Colony Count, Microbial; D004311:Double-Blind Method; D005260:Female; D005782:Gels; D015438:Health Behavior; D006801:Humans; D007223:Infant; D008137:Longitudinal Studies; D008297:Male; D009055:Mouth / Q000382:microbiology*; D009910:Oral Hygiene / Q000706:statistics & numerical data; D018709:Statistics, Nonparametric; D013290:Streptococcal Infections / Q000188:drug therapy*; D013295:Streptococcus mutans / Q000187:drug effects*
D000891:Anti-Infective Agents, Local; D005782:Gels; D002710:Chlorhexidine