Factors and Regional Differences Associated with Self-reported Dental Caries in 3-year-old Children in Kanagawa Prefecture

<p> To contribute to the prefectural oral health policy, we examined individual factors associated with dental caries and regional differences. Analysis of secondary data from a survey of 3-year-old children conducted in the Kanagawa Prefecture Resident Survey on the Actual Health Situation in 2020 was performed. Data on self-reported dental caries, attributes, and dental health behaviors of 4,741 participants aged 3 years were analyzed. The associations among the presence, absence, or unknown status of dental caries and other survey items were examined by cross-tabulation. Multinomial logistic regression analysis was conducted with the presence, absence, or unknown status of dental caries as the objective variable and other items as the explanatory variables. A quantitative text analysis of open-ended responses regarding the sense of burden or difficulty in finishing-toothbrushing by parents was conducted. The multinomial logistic regression analysis revealed significant odds ratios of 1 or higher (p<0.05) in the presence of dental caries (reference category: no caries) for the following areas of residence: Sagamihara city, East Shonan, and western part of the prefecture (reference: Yokohama city). The analysis also showed significant odds ratios for the second and third child in birth order (reference: first-child), eating while watching TV (reference: none), daily consumption of sweet snacks and/or sweetened drinks (reference: none), not brushing teeth daily (reference: yes), burden or difficulty in finishing-toothbrushing by parents (reference: none), do not use fluoride-containing toothpaste daily (reference: yes), and yes or unknown answers for experience of visiting dentist (reference: no experience). The quantitative text analysis revealed many difficulties, such as reluctance in opening their mouths. In conclusion, late birth order, habit of eating while watching TV, frequent consumption of sweets and sweetened drinks, lack of daily tooth brushing, parents’ sense of burden and difficulty in finishing-toothbrushing by parents, lack of daily use of fluoride toothpastes, and unknown answers for experience of visiting dentist were associated with dental caries among 3-year-old children in Kanagawa Prefecture, and regional differences remained even after adjustment for these individual factors.</p>