Objectives: To establish the prevalence and possible relationship of oral Streptococcus mutans colonization in mother-child pairs.
Design and setting: An analytical cross-sectional study was carried out at a well-baby evaluation clinic held at the Public Dental Clinic, Varberg, Sweden.
Sample and methods: Two hundred preschool children, 100 of which were 18 months old and the remaining 100 were 3 years old, and their mothers attended the clinic. All mothers were interviewed and their children's medical history, oral hygiene routines and dietary habits established. All children were clinically examined. The presence and level of S. mutans was estimated in the mother-child pairs with the aid of the Strip mutans chair-side test.
Results: Nearly 50% of mothers exhibited high levels of salivary S. mutans, prevalence among the 18-month- and 3-year-olds was 30% and 42%, respectively. A statistically significant (P < 0.01) mother-child relationship was found; a greater presence in mothers led to a higher number of children found harbouring the bacteria. Logistic regression analysis found that high maternal S. mutans levels (P < 0.001), daily sweet intake (P < 0.01) and sugary drinks in feeding bottles (P < 0.05) were significant factors for S. mutans colonization in children. Absence of daily toothbrushing and use of feeding bottles at night failed to fit into the model. Caries prevalence (initial and manifest decayed surfaces) was significantly related to S. mutans colonization (P < 0.01).
Conclusion: The results support the concept of vertical transmission (mother-child), emphasizing the importance of the dietary component, and justifying a primary preventive approach with targeted action directed at mothers with high levels of S. mutans colonization.