Birth order is associated with caries development in young children: a register-based cohort study.

BACKGROUND: Birth order has been shown to affect the health of the child; less is known, however, about how birth order affects caries development in children. Thus, the present study investigated the association between birth order and dental caries development in young children. METHODS: This retrospective registry-based cohort study included all children born in 2000-2003 who were residing in Stockholm County, Sweden, at age 3 years (n = 83,147). The study followed the cohort until subjects reached 7 years of age. Children with registry data on dental examinations and sociodemographic characteristics at ages 3- and 7 years constituted the final study cohort (n = 65,259). The outcome variable was "caries increment from age 3- to 7 years" (Δdeft > 0) and the key exposure, "birth order", was divided into five groups. A forward stepwise logistic binary regression was done for the multivariate analysis with adjustments for sociodemographic factors. RESULTS: At age 3 years, 94% had no fillings or manifest caries lesions. During the study period, 22.5% (n = 14,711) developed dental caries. The final logistic regression analysis found a statistically significant positive association between birth order and caries increment. Further, excess risk increased with higher birth order; with the mother's first-born child as reference, risk for the second-born child was OR 1.17, 95% CI = 1.12-1.23; for the third-born child, OR 1.47, 95% CI = 1.38-1.56; for the fourth-born child, OR 1.69, 95% CI = 1.52-1.88; and for the fifth-born or higher birth-order child, OR 1.84, 95% CI = 1.58-2.14. CONCLUSIONS: These findings show that birth order influences caries development in siblings, suggesting that birth order can be regarded as a predictor for caries development in young children. This factor may be helpful in assessing caries risk in preschool children and should be considered in caries prevention work in young children with older siblings.

Socioeconomic Determinants, Maternal Health, and Caries in Young Children.

INTRODUCTION: Maternal health during pregnancy plays a part in child health, and several conditions have been associated with adverse child outcomes. OBJECTIVES: To determine the socioeconomic determinants and maternal health factors associated with dental caries in young children. METHODS: This cross-sectional study is part of a register-based cohort study including all children who were born from 2000 to 2003 and were residing in Stockholm County, Sweden, at age 3 y (n = 73,658). The study followed the cohort until individuals were 7 y old. The final study cohort comprised all children examined at 3 and 7 y (n = 65,259). Data on socioeconomic conditions, maternal health, and maternal health behavior were extracted from Swedish national registries. The multivariate analyses used 2 outcomes: caries experience at age 3 and 7 y (deft > 0 [decayed, extracted, and filled teeth]). RESULTS: The results of this study show that socioeconomic and maternal health behaviors during pregnancy are important determinants of oral health in their preschool offspring. When all significant risk factors were present, the cumulative probability of being diagnosed with dental caries at age 7 y was 75%. CONCLUSION: This study also showed that maternal obesity and smoking during pregnancy were predictors of dental caries in preschool children. Strategies must be developed for increasing maternal motivation and self-efficacy and providing mothers with knowledge and caries-preventive tools. KNOWLEDGE TRANSFER STATEMENT: The results of this study inform clinicians about the importance of including a more detailed history regarding maternal health and maternal health behaviors during pregnancy to assess caries risk in preschool children. Education, income, and other socioeconomic factors are difficult to modify in the short term. Therefore, strategies must be developed to increase parental motivation and self-efficacy to give parents the determination, knowledge, and tools for prevention.

Caesarean Section Does Not Increase the Risk of Caries in Swedish Children.

Caesarean section has been shown to affect the health of the child. Only a few studies have investigated whether the mode of delivery is associated with dental caries, and they present conflicting results. Our study investigated whether dental caries was associated with delivery method in Swedish preschool children. This retrospective register-based cohort study included all children born from 2000 to 2003 who were residing in Stockholm County, Sweden, at 3 y of age (n = 83,147). The study followed the cohort until individuals were 7 y of age. Children examined at 3 and 7 y constituted the final study cohort (n = 65,259). We dichotomized the key exposure "delivery starts by caesarean section" and analyzed it in univariate analyses as well as in multivariate analyses. The multivariate analyses used 3 outcomes: caries experience at age 3 (deft >0 [decayed, extracted, and filled teeth]), caries increment between 3 and 7 y of age (Δdeft > 0), and caries experience at age 7 (deft > 0). Of the final cohort, 15% (n = 9,587) were delivered by caesarean section. At 3 y of age, the results showed no statistically significant association between caesarean section and caries experience (odds ratio = 0.92, 95% confidence interval [CI] = 0.82 to 1.04). Between 3 and 7 y of age, the association of caesarean section on caries increment was 0.88 (95% CI = 0.83 to 0.94) and at 7 y of age, 0.88 (caries experience; 95% CI = 0.82 to 0.94). Higher mean values for caries experience and caries increment were observed in vaginally delivered children. We found that preschool children who were delivered by caesarean section do not represent a group with an excess risk of developing dental caries. Furthermore, the statistically significant associations with caries increment and caries experience at age 7 were negative. Knowledge Transfer Statement: Children born by caesarean section are at greater risk of developing asthma and obesity. The proportion of elective caesarean sections without a medical indication has increased over the years; therefore, it is important to know how this mode of delivery affects oral health of the child. The results show that children who are delivered by caesarean section are not at greater risk of developing dental caries, and clinicians can use these findings in their risk assessment.

Influence of approximal caries in primary molars on caries rate for the mesial surface of the first permanent molar in swedish children from 6 to 12 years of age.

The objective was to assess the influence on the caries rate for the mesial surface of the first permanent molar (6m) of the caries status of the distal surface of the second primary molar (05d) in children from 6 to 12 years of age. The study design was retrospective and included 374 children with an average of 5 sets of bite-wing radiographs. The mean age of the children was 6.7 years when the first bite-wing radiographs were taken and 11.5 years at the time of the latest radiographs included in the study. The approximal surfaces were classified according to a scoring system: 0 = no visible radiolucency, 1= radiolucency in the outer half of the enamel, 2 = radiolucency in the inner half up to the enamel-dentin border, 3 = radiolucency with a broken enamel-dentin border but with no obvious involvement of the dentin, 4 = radiolucency with obvious spread in the outer half of the dentin, and score 5 = radiolucency in the inner half of the dentin. The influence of the status of 05d on the caries rate for 6m (state > or =2) was assessed by using a model for dependence between the two neighbouring surfaces. Presence or absence of approximal caries in the distal surface of the first primary molars (04d) and/or the mesial surface of the second primary molars (05m) at the time of eruption of 6m was also related to the caries rate for 6m. The caries rate for 6m was 15 times higher if 05d had developed enamel/enamel-dentin border caries (state 2 or 3) compared to a radiographically sound 05d (state 0 or 1). No significant increase in the caries rate for 6m was found when 05d had deeper unrestored dentin caries than when 05d had superficial caries (state 2 or 3). Furthermore, for preventing caries in 6m, no benefit could be found from restoring an 05d with dentin caries with amalgam as opposed to leaving the carious lesion unrestored until exfoliation. The caries rates for 6m and 05d were 3.4 and 2.7 times higher, respectively, in the presence of dentin caries/restoration in 04d/05m compared to absence of dentin caries in these molar surfaces at the time of eruption of 6m. In conclusion, the caries rate for 6m depended on the status of 05d and increased 15 times if 05d had enamel/enamel-dentin border caries compared to a sound 05d. Deeper unrestored or restored dentin lesions in 05d did not result in a higher caries rate for 6m compared with more shallow carious lesions in 05d.