Main

Br Dent J 2017;223: 533–539; http://dx.doi.org/10.1038/sj.bdj.2017.837

Credit: © Peter Dazeleyk/Getty Images Plus

Sufferers of bulimia nervosa attempt to control their weight by forcing themselves to be vomit, an act often referred to as 'purging'. It is estimated that 8% of women suffer from bulimia at some point, generally beginning at around the age of 18 or 19.1 People who have bulimia will often keep their eating disorder secret so it is important that healthcare professionals are aware of the signs; particularly dentists, considering the damaging effect of frequent vomiting on the dentition.

In this review, Tim Newton and co-authors focused on the findings of ten papers. These papers demonstrated that bulimics suffered most commonly with dental erosion, dental caries and reduced salivary secretions. However, they do note that bulimics' dietary choices could possibly account for caries and erosion, as previous studies have noted that binge eating often includes sugary foods. The authors note that bulimia is more prevalent amongst women than men (they cite one study which showed that lifetime prevalence of bulimia is 1.1% amongst women and 0.1% amongst men). They also point out that bulimia causes a reduced salivary flow rate which in turn is detrimental to the maintenance of oral health.

The effect of gastric acid, which has a mean pH of 2.9, on teeth is clearly a major cause of dental erosion amongst bulimics. The authors point out the clear relationship between duration of self-induced vomiting and the number of lesions on the teeth.

The authors identified some cases where patients did not demonstrate a correlation between vomiting and erosion; however, they note that this may be because those patients knew not to brush their teeth immediately after vomiting.

There are conflicting reports on caries levels amongst bulimics. Reduced salivary flow rate and the dietary choices of binge eaters may account for an increase in dental caries, but better oral hygiene and the suggestion that S. mutans are unable to metabolise below pH values of 4.2 means that bulimics sometimes demonstrated fewer DMFT than the controls. Newton et al. do stress that S mutans can adapt and remain active at lower pH levels, therefore higher levels of S. mutans could increase the risk of caries. Further research is required regarding dental caries risk amongst bulimics as some studies found no difference in DMFT between bulimics and control groups.

The review authors conclude that it is not only vomiting that affects bulimics' teeth, but also medication and dietary habits. They suggest that as dental care professionals are in a prime position to spot signs of bulimia and also to advise on oral hygiene post-vomiting, it is important that this topic is covered in the dental curriculum.

By Jonathan Coe

Listen to Stephen Hancock's summary of this research via the BDJ Youtube channel http://bit.ly/BDJYouTube