Brushing your teeth after every meal might seem like the right way to keep them strong and healthy, but dentists have warned that this can actually do more harm than good – especially if you have just eaten a rich meal, washed down with an acidic beverage. According to recent research, brushing within half an hour of eating can do real damage to the dentin layer beneath the enamel, because the acid levels in the mouth are higher after eating and brushing cannot remove the acid without damaging the tooth structure. Dr Howard R. Gamble, president of the Academy of General Dentistry spoke to the New York Times, explaining that ‘with brushing, you could actually push the acid deeper into the enamel and the dentin.’
As part of a study to test the theory, volunteers wore human dentin samples in their mouth and tested different brushing routines; the results showed that brushing within an hour of drinking something acidic ‘stripped’ the teeth of their minerals, and waiting twenty minutes after a soft drink also did considerable damage. However, there is some good news, as the effect seems to be minimalised after about an hour; the researchers who carried out the study revealed that ‘after intra-oral periods of 30 and 60 mins, wear was not significantly higher than in unbrushed controls. It is concluded that for protection of dentin surfaces, at least 30 mins should elapse before tooth brushing after an erosive attack.’