The purpose of this study is to conduct a community based, randomized control trial to determine if the use of chlorhexidine mouth rinse and xylitol-sweetened chewing gum will reduce the vertical transmission of caries between Alaska Native mothers to their infants.

Alaska Native children are disproportionately affected by early childhood caries, compared to all U.S children. Dental care needs for adults and children in rural Alaska far exceed the acute care and prevention resources available. As a result, there is a high level of dental morbidity present among adults that likely contributes to early transmission of mutans streptococci (MS) from adult caregivers to infants in the household. Furthermore, the cultural practice of pre-mastication of solid food for infant feeding amplifies the transmission of oral secretions from adult to child. The prevention of early MS acquisition and subsequent caries in infants and toddlers requires efforts starting at birth. Since Alaska Natives are a rural population at high risk for caries, interruption of vertical transmission of MS using a combination of improved oral hygiene practices, and topical antimicrobials and bacteriostatic agents may be an ideal prevention strategy for childhood caries. Chlorhexidine and xylitol are two agents that have been shown to reduce dental decay and MS counts.

The specific aim of this proposal is to conduct a community based, randomized blinded trial to determine if the serial use of chlorhexidine and xylitol will reduce the vertical transmission of caries between Alaska Native mothers and infants. We hypothesize that a two week period of twice-daily chlorhexidine mouthwash use prior to delivery, followed by a subsequent two year period of maternal xylitol gum use, will lead to a significant reduction in the age-specific prevalence of early childhood caries at 12 and 24 months of age among the offspring of mothers in the intervention group, compared to control group mothers. We also hypothesize that, compared to controls, mothers and children in the intervention group will have significant reductions in oral MS counts at each follow-up interval.

If proven successful, this intervention could have a significant impact on the prevalence of caries among young Alaska Native children and other population groups at high risk for childhood caries.

• Drug: Chlorhexidine mouth rinse
• Drug: Xylitol chewing gum

• primiparous or multiparous pregnant Alaska Native mothers of all ages
• in the last month of pregnancy
• reside in the health service delivery area of the native health corporation, in one of the communities with the highest birth counts from 2002
• eligible for obstetric care from the health corporation
• plan to give birth to their infant in a specified city of Alaska