A Case-control Study Comparing 30% of Children with the Highest DMFS Score and Children with No Caries in Southern China

Objective: To explore the risk factors of children with a high decayed, missing and filled surfaces (DMFS) score compared with children with no caries. Methods: Seven kindergartens in Conghua, located in suburban Guangzhou in Southern China, were selected. A total of 401 3- to 4-year-old children were examined for dental caries status, developmental defect of enamel (DDE) and visible plaque index (VPI). Data on children's oral health behaviour, parents' oral health knowledge, attitude and behaviour and other related information were collected by a structured questionnaire completed by their parents. A total of 120 children (30%) with the highest DMFS score (DMFS >= 7) and all 118 caries-free children were chosen for a case-control analysis to explore the risk factors. Results: In bivariate analysis, age at start of tooth brushing, frequency of tooth brushing, frequency of sweet food consumption, pacifying children with sweet food, bottle feeding with sugary drinks, having visited a clinician, VPI, family income, parents'education level, parents' tooth brushing habit, and parents' oral health knowledge and attitude were associated with caries experience in the children. The results of logistic regression analysis showed that the factors associated with high DMFS score were VPI, frequency of sweet food consumption, family income, parents' oral health attitude and having visited a clinician. Conclusion: The results of this study suggest that brushing teeth in an effective way, controlling sugar consumption and educating parents to have a more positive attitude toward oral health are important components in caries prevention among children in Southern China. Keywords: caries, epidemiology, risk assessment