mch
TRANSCRIPT
Mother-child transmission of mutans streptococci
Birth
MS5 y
N = 38First Tooth6.8 ± 1.4 mo.
19 33
The Window of Infectivity for MS.(Caufield, Pediatric Dentistry 1997, 19: 491-8)
26
The window of infectivity for mutansstreptococci
The earlier the mutans streptococci are colonized, the
higher is the risk for caries
Transmission of mutans streptococci
• The mother (infecting person) has high salivary mutans streptococci counts
• Several daily saliva contacts between the child and the mother must take place
Methods to prevent the acquisition of mutans
streptococci
• Information on mother-child transmission of ms, advice on diet and oral hygiene
• Chemical methods (chlorhexidine)
• Xylitol
Mother-child study
Eva Söderling and Pauli Isokangas
Institute of Dentistry, Turku
Ylivieska Health Centre, Ylivieska
Subjects• At baseline 195 mothers with
high salivary mutans streptococci counts (60% of all mothers)
• 2-year examination: 169 mother-child pairs
• 6-year examination: 147 children
Study groups
• Xylitol group: xylitol chewing gum 4 times a day
• Fluoride (F; control) group: fluoride varnish (2.26%) treatments 2 times a year
• Chlorhexidine (CHX) group: CHX varnish (40%) treatments 2 times a year
All interventions discontinued when the child was 2 years old
Xylitol chewing gum
Only the mothers used xylitol/were treated with varnish; no additional
treatments to children
Results
Mutans streptococci of the mothers:• High salivary
mutans streptococci counts in all groups throughout the study
• No differences between the study groups
7.5
7.0
6.5
6.0
5.5
5.0
4.5
4.0
Pregnancy 0.5 1 2Age of child (years)
F
CHX
Xyl
IogC
F/m
l
Mutans streptococci of the 2-year-old children (Söderling et al., JDR 2000)
• The child’s risk of having mutans streptococci colonization in the dentition was 5-fold in the F group and 3-fold in the CHX group as compared to the Xylitol group
60
50
40
30
20
10
0CONTROL CHX XYLITOL
n=33 n=28 n=103
%
Caries occurence in children
• At the age of 5 years the need of restorative treatment was 71-75% lower in the Xylitol group as compared to the F and CHX groups
• The occurence of caries and early mutans streptococci colonization were in agreement
CHX
Control
Xylitol
Age
dmf
3
2
1
00 1 2 3 4 5 6
Prevention of Maternal-Prevention of Maternal-Infant Transmission of Infant Transmission of
CariesCaries
Prevention of Maternal-Prevention of Maternal-Infant Transmission of Infant Transmission of
CariesCaries
A Randomized Clinical TrialA Randomized Clinical Trial
Investigator Affiliation
University of Washington Schools of Dentistry, Medicine and Public
Health
Departments of Dental Public Health Sciences, Pediatrics, Health Services, Pediatric Dentistry
Background• Rates of early childhood caries 4.5 fold
higher among Alaska Natives• High rates of caries likely related to:
– high load of oral bacteria that cause caries• S. mutans, S. sobrinus• early acquisition
– decreased fluoride exposure– large amounts of refined sugar in diet– poor oral hygiene
Specific Aim
• To determine if the infants of pregnant mothers who use CHX mouth rinses for two weeks, followed by xylitol gum use for two years, experience less dental decay compared to infants of mothers who do not use these interventions
Methods: Design
• Randomized controlled trial
• 2 arms: intervention vs. control
• double-blinded
Yukon-Kuskokwim Delta
Subjects• Enroll: Pregnant mothers at
36-38 weeks of gestation• Track outcomes:
– Mothers– Liveborn children who are offspring of
enrollees
• Exclude: infants born in Anchorage, infants with congenital anomalies
Intervention: Both Groups
• Dental hygiene and exam
• Restoration of caries and extractions as necessary
• Dental and dietary counseling/education
• Toothbrushes and toothpaste
Intervention Group Only
• Chlorhexidine rinses, twice a day for two weeks; starts at enrollment
• Xylitol gum 5.1 grams per day (3x/day) for two years
Outcome Assessment• Outcomes of interest
–caries among infants at 1 and 2 years of age• all enrolled children
• deft
–S. mutans counts for mothers and infants at same time intervals • for subset (n=30) only
Data Collection• Baseline:
– maternal dental exam– maternal gingival culture (subset)– maternal oral health questionnaire
• T1 (infant age= one year) – oral health questionnaire– infant dental exam– infant and maternal gingival cultures (subset)
Data Collection
• T2 (infant age=2 years)
–oral health questionnaire
–infant dental exam
–infant and maternal gingival cultures (subset)
Analysis
• Compare rates of caries between intervention and control groups– (unit of analysis: child or teeth)
• Compare S. mutans counts between groups
• Control for confounding factors, if present
Potential limitations
• Compliance with intervention• Blinding• Misclassification of exposure
– e.g. control mom uses intervention– mother doesn’t rear child
• Intensification of exposure– e.g. whole family uses gum
Sample Size Estimates• N=375 births/year
– Exclude 25% born in Anchorage– Assume 10% refusal rate– Enroll approximately 125 in each group– Assume 80% follow-up at two years– Need about 200 at final follow-up
• About 90% power to detect a 50% reduction in the intervention group
Future studies…Future studies…Future studies…Future studies…
Xylitol administration with a slow-release pacifier for AOM and ECC?
Diet and dental caries
Subsidizing toothpaste, introducing xylitol snacks
What is most impressive about xylitol is its safety
Effectively addressing caries will require new and better tools for public health
THANK YOU