Kids' dental cavities not just bad genes, lifestyle also a factor: Report

Environmental factors appear to play a bigger role than genetics in shaping children’s risk for cavities, a study of Australian twins suggests.

Researchers followed 345 twins from 24 weeks’ gestation through six years of age, when they all had dental checkups. At age six, 32 per cent of the kids had tooth decay and 24 per cent of the children had advanced cavities.

To see how much genetics might shape the risk of cavities, researchers looked at how often both kids got cavities in pairs of identical twins — who have identical genetic variations — and fraternal twins - who typically share about half of their variations.

The risk of both siblings developing any form of tooth decay or advanced cavities was similar for identical and fraternal pairs, suggesting that genetics doesn’t explain much of the risk for these oral health problems.

“Therefore, risk factors seem to be mostly environmental and are potentially modifiable,” said lead study author Mihiri Silva of the University of Melbourne and the Murdoch Children’s Research Institute at Royal Children’s Hospital in Melbourne.

“This might debunk the idea that individuals are genetically destined to have poor teeth and should drive us to find ways of addressing the risk factors that we know are important for dental health,” Silva said by email.

Worldwide, an estimated 60 to 90 per cent of school age children have tooth decay, potentially resulting in pain, infection and hospitalisation, researchers note in Pediatrics. Toothache can also result in school absence, poor nutrition, compromised growth and development, and impaired quality of life for children and parents alike.

Childhood cavities are also the strongest predictor of poor oral health in adulthood, the study team writes.

While some previous research has called into question the role genetics may play in causing cavities, research to date hasn’t offered a clear picture of what role environmental or lifestyle factors might play in this risk.