Brushing only partly protects children's teeth
Tooth brushing only partly protects against the effects of sugary snacks on children's teeth, research suggests.
A study of almost 4,000 pre-school children showed snacking habits were most strongly associated with decay.
Researchers found children who snacked all day - compared with just eating meals - were far more likely to have dental decay.
The study shows that relying on tooth brushing alone to ward off dental decay in children under five is not enough.
The study also said parental socioeconomic factors, such as the mother's education level, explained more of the difference in children's dental decay than diet or oral hygiene.
The researchers said that even though primary teeth were temporary, "good oral hygiene habits are set in childhood, and this relates both to diet and tooth brushing".
Social scientists from the University's of Edinburgh and Glasgow used statistical models and survey data to predict dental decay by the age of five.
They used data collected on diet and oral hygiene from repeated observation of children from ages two to five.
Snacking was the factor most strongly associated with decay, with children who snacked all day without eating meals having twice the chance of decay compared with those who did not snack at all.
There was an incremental association between lower frequencies of tooth brushing at the age of two and higher chances of dental decay at five.
Children who brushed less than once per day or not at all at the age of two had twice the chance of having dental decay at five compared with children who brushed their teeth twice per day or more often.
The study is published in the Journal of Public Health.
Lead researcher Dr Valeria Skafida, of the University of Edinburgh's School of social and political science, said restricting sugar intake was desirable both for broader nutritional reasons and for children's dental health.
Dr Skafida said: "Even with targeted policies that specifically aim to reduce inequalities in children's dental decay it remains an ongoing challenge to reduce social patterning in dental health outcomes."
Study co-author, Dr Stephanie Chambers, of the social and public health sciences unit at University of Glasgow, said: "Among children eating sweets or chocolate once a day or more, tooth brushing more often - once or twice a day or more - reduced the likelihood of decay compared with less frequent brushing."
The researchers used data from the Growing Up in Scotland study - a social survey which follows the lives of children from infancy through to their teens.
The research was supported by The British Academy, the Medical Research Council and the chief scientist office of the Scottish government Health Directorates.