Methods: A random sub-sample of 738, 12-year-old students from the ‘Children of 1997’ birth cohort was recruited. Clinical assessment for dental caries was performed according to the WHO criteria. Dental caries was measured as the number of decayed, missing and filled surfaces (DMFS). The students were classified into five growth trajectories based on their weights from birth to 12 months. The association of growth trajectories with subsequent dental caries experience in permanent dentition until the child’s 12 years old was explored through multivariable negative binomial regression adjusted models
Results: Four hundred and eighty-five students (65.7%) had growth trajectories. Students with both the slowest growth trajectory (smallest birth weight and slow weight gain) and the fastest growth trajectory (heavier birth weight and accelerated weight gain) had significant higher DMFS until 12 years of age than the ‘normal’ growth trajectory (average birth weights and average weight gain). Adjusted incident rate ratios of dental caries were 2.36 (95% CI 1.25 ~ 4.47) for the slowest growth trajectory and 2.04 (95% CI 1.08 ~ 3.87) for the fastest growth trajectory compared with the normal one. After additionally adjusted for birth weight z-score, incident rate ratios of dental caries were 2.79 (95% CI 1.39 ~ 5.61) for the slowest growth trajectory and 1.94 (95% CI 1.02 ~ 3.69) for the fastest growth trajectory compared with the normal one.
Conclusions: Among this lifecourse sample (‘Children of 1997’), slow growth infants born with low birth weight and fast growth infants with high birth weight were more susceptible to dental caries of permanent teeth at 12 years of age.