A mother's mental health may play a larger role in a child's toothbrushing habits than previously thought.

It is no secret that brushing your teeth twice a day is highly effective in promoting healthy teeth and gums. The International Association of Pediatric Dentistry advocates brushing with toothpaste containing fluoride to prevent decayed, missing, or filled teeth – known as childhood dental caries (ECC) – in children.

Parents are instrumental in instilling good dental habits in their children.

In Japan, there is a worryingly high prevalence of ECC among children aged 3 years old. Postpartum depression and/or lack of affection caused by bonding disorders hamper a mother's ability to cultivate healthy dental practices in children, and researchers were keen to explore this link.

Dr Shinobu Tsuchiya from Tohoku University Hospital led a research group that analyzed approximately 80,000 mother-infant pairs from the Ministry of Environment's Japan Environment and Children's Study.

They found children with mothers suffering from postpartum depression or bonding disorders brushed their teeth less often. Likewise, the frequency with which children brushed their teeth increased when mothers showed strong affection towards their children.

The research group hopes their research will foster greater mental support and management for mothers and that doctors will incorporate these factors when assessing children's oral health.

"A mother's psychological well-being provides valuable screening information for identifying children at a high risk of ECC," said Tsuchiya

In future studies, Tsuchiya and her team hope to examine other environmental influences on poor oral health.