Dental Caries and Oral Health Practices: A Life Course Perspective in Egypt

Aims: A life course approach may explain how age and oral health practices interact to affect caries risk. This study assessed the association between untreated decay and children’s oral health practices, and how age modified this relationship. Methods: A cross-sectional household survey of 823 children was conducted in rural Egypt, 2019-2022. Age groups were categorized as: 0-<3, 3-<6, 6-<12, and 12-<18 years-old. Negative binomial regression assessed the relationship between dependent (number of decayed teeth per the World Health Organization criteria), and explanatory variables: daily toothbrushing, daily consumption of ≥2 types of sugary foods/drinks, and dental visits last year. Confounders were village of residence, child’s sex, and mother’s education. Interaction by age was assessed by calculating p -values. Adjusted means and effect sizes were calculated. The ethics committee of the Faculty of Dentistry, Alexandria University approved the study. Results: Toothbrushing and dental visits were associated with significantly higher number of decayed teeth (B= 0.1 and 0.3). Age significantly modified the association between practices and the number of decayed teeth. There were no significant differences in the number of decayed teeth between children who brushed daily and those who did not and children who consumed ≥2 types of sugars and those who did not with effect sizes indicating different magnitude and direct of impact of toothbrushing (effect sizes= -0.2, 0.1, 0.3 and 0.5) and sugar consumption (effect sizes= -0.1, 0.1, 0.2 and -0.5). Also, there were no significant differences between children who visited the dentist and those who did not except in the 3-<6 years old group (effect sizes= 0.6, 0.3, 0.2 and 0.4). Conclusions: The magnitude and direction of the association between oral health practices and decay differed by age, and was strongest in 12-18-year-olds, except for dental visits, which had the greatest impact in 3-<6-year-old children. Recognising this influence is vital for designing tailored interventions across life stages.