Environmental factors appear to play a bigger role in developing dental caries than genetics, according to a new study of twins.
Authors set out to look at risk factors by collecting data on twins from 24 weeks’ gestation through age 6 years when the children underwent dental exams.
Among the 345 children who underwent dental assessments, 32% had signs of caries. In 29 pairs, both children had caries, while in 33 pairs, only one child was affected, according to “Genetic and Early-Life Environmental Influences on Dental Caries Risk: A Twin Study,” (Silva MJ, et al. Pediatrics. April 26, 2019, https://doi.org/10.1542/peds.2018-3499).
About 24% of the children had advanced caries. In 26 pairs, both had advanced caries, and in 31 pairs, only one child had advanced caries.
Monozygotic twins were no more likely to have the same outcomes than dizygotic twins.
“Our findings reveal that despite the biological plausibility, genetic factors are relatively less important determinants of caries risk than shared environmental factors,” authors wrote.
Adjusted models showed risk factors for caries were lack of community water fluoridation, the enamel defect hypomineralized second primary molars (HSPM) and maternal obesity.
Authors said the findings bolster previous studies that found links between dental caries and both lack of water fluoridation and HSPM. The impact of maternal obesity could be biological, or a mother with a poor diet could also be giving her child unhealthy food.
“These findings can help pediatricians and other health professionals involved in the care of children instigate preventive modalities early in life, before the onset of clinical disease and damage to dental tissues,” authors wrote.
