Background Maternal nutrition during pregnancy may influence offspring health through developmental mechanisms. However, epidemiological evidence of the association between maternal vitamin A (VA) intake and the experience of dental caries in children remains limited. Therefore, in this study, we focused on retinol, the primary component of VA, and hypothesized that higher maternal retinol equivalents (RE) intake during pregnancy is associated with a lower experience of dental caries in the offspring. Materials and methods This cross-sectional study was conducted as an Adjunct Study to the Japan Environment and Children's Study and included 144 children aged 7–8 years. Maternal VA intake was estimated as energy-adjusted RE (μg/1000 kcal/day) using a validated food frequency questionnaire. The experience of dental caries was evaluated using the decayed and filled primary teeth (dft) index as an outcome variable. Multivariable negative binomial regression models were used to estimate incidence rate ratios (IRRs), treating maternal RE intake as a continuous variable. The models were adjusted for child-related factors (sex, age) and maternal socioeconomic factors. Results The median maternal RE intake was 274.6 μg/1000 kcal/day. In the multivariable analysis, each 100 μg/1000 kcal/day increase in maternal RE intake was associated with lower dft (IRR = 0.854, 95% CI = 0.760–0.959, p = 0.008). Conclusion Higher maternal RE intake during pregnancy was associated with lower dental caries experience in the offspring. Further prospective studies are needed to confirm this association.
Tooth development begins with the invagination of the epithelium and culminates in the formation of the mature tooth, a process regulated by various transcription factors. Pitt-Hopkins syndrome is a disorder characterized by craniofacial abnormalities; heterozygous mutations in the TCF4 gene are associated with distinctive facial features and severe psychomotor developmental delay. However, the role of TCF4 in tooth formation remains unclear.Using yeast two-hybrid and co-immunoprecipitation assays, we demonstrated that AmeloD, a tooth-specific transcription factor, binds directly to TCF4. Immunostaining and single-cell RNA sequencing analyses revealed that TCF4 is expressed in both dental epithelium and dental mesenchymal cells. Overexpression of AmeloD in the dental epithelial cell line SF2 induced TCF4 expression, whereas TCF4 overexpression did not induce AmeloD expression. Although stimulation with the nerve growth factor NT-4 normally induces the expression of differentiation markers such as Ambn and Enam in SF2 cells, we found that TCF4 overexpression inhibited this NT-4-induced cellular differentiation. Furthermore, this inhibitory effect was abolished by the overexpression of AmeloD.These findings reveal a novel function of TCF4, it directly inhibits AmeloD function through physical interaction. This insight is significant for elucidating the causes of the dental phenotypes observed in Pitt-Hopkins syndrome.
Eating speed and chewing frequency may be associated with body size; however, longitudinal evidence of their associations with anthropometric trajectories is limited. We examined the associations of chewing-related behaviours assessed in the third grade with anthropometric trajectories and incident overweight among Japanese elementary-school children.Children participating in the Kuroishi Oral Health Study who were not overweight at baseline and had at least one follow-up measurement were included in the analysis (n = 412; 54.9% girls). Eating speed, chewing frequency, and difficulty eating hard foods were assessed using a questionnaire completed by the guardians. Body mass index (BMI), height, and body weight from the third to sixth grades were derived from school health records and analysed using linear mixed-effects models. Cox proportional hazards models were used to examine incident overweight.Fast eating and infrequent chewing were associated with higher BMI and body-weight trajectories; however, neither was associated with height trajectories. Difficulty eating hard foods was not significantly associated with anthropometric trajectories. In the combined chewing-habit analysis, children with both fast eating speed and infrequent chewing showed the highest BMI and body-weight trajectories, with differences emerging earlier than in the other groups. Fast eating and infrequent chewing were associated with incident overweight before adjustment for baseline BMI; however, the associations were not significant after adjustment.Eating speed and chewing frequency may represent behavioural markers of an emerging higher-BMI trajectory during childhood. These findings underscore the importance of considering everyday chewing habits as behavioural factors associated with weight-related growth patterns in children.
Purpose This randomized controlled trial evaluated the clinical efficacy of a theobromine toothpaste compared with a low-fluoride toothpaste in reducing dental plaque and improving gingival health in children. Methods Forty children aged 6–9 years were enrolled in a double-blind randomized controlled trial and allocated into two equal groups: a control group using low-fluoride toothpaste containing 500 ppm fluoride and a test group using a theobromine toothpaste containing approximately 1.3% w/w theobromine. All participants received standardized oral hygiene instructions and identical toothbrushes. Plaque accumulation was assessed using the Turesky modification of the Quigley–Hein Plaque Index, and gingival health was evaluated using the Löe and Silness Gingival Index. Clinical assessments were performed at baseline before intervention (T0), after 1 week (T1), after 2 weeks (T2), and after 3 weeks (T3). Data were analyzed using independent samples t-test, paired samples t-test, Mann–Whitney U test, and Wilcoxon signed-rank test at p < 0.05. Results Both groups showed significant reductions in plaque scores over time. No significant difference in plaque scores was observed between the groups at T1. However, the theobromine group showed significantly lower plaque scores than the low-fluoride group at T2 and T3. Gingival index scores improved significantly within both groups from baseline, but no significant differences were found between the groups at any time point. No adverse events were reported. Conclusion The theobromine-containing toothpaste showed greater short-term antiplaque efficacy than low-fluoride toothpaste after 2 and 3 weeks of use. Longer-term trials are needed to confirm its sustained efficacy and caries-preventive potential.
