Inside Look

Bulimia and Oral Health: Insights from Pediatric Dental Expert Dr. Michael Roberts

Jan 16, 2024

I recently spoke with pediatric dentist, Michael Roberts, DDS, MScD, about the oral implications of eating disorders. Dr. Roberts is the Dr. Donald and Mrs. Alexandra Henson Distinguished Professor at the Adams School of Dentistry, Department of Pediatric Dentistry and Dental Public Health, at the University of North Carolina. Prior to serving as chair of the UNC pediatric dentistry program as well as their graduate program director, he served as Deputy Clinical Director at the National Institute of Dental Research, NIH. Dr. Roberts has had an interest in the oral effects and management of eating disorders among adolescents for many years. He has published over one hundred articles in professional journals and contributed to three textbooks.



Patients struggling with bulimia often use vomiting as a source of purging. The behavior can take place multiple times per day or less. Regardless of the exact frequency, if the behavior is a regular event, what effects can occur inside the mouth and throughout the entire craniomaxillofacial region?

Well, the one that everyone recognizes and thinks of is the stomach acid dissolving the enamel of the teeth with the lingual or inside surfaces of the upper front teeth being at most risk. Whenever an individual purges, the stomach acid removes about ten microns of enamel from the affected teeth. When enough enamel has actually been lost for an oral health specialist to recognize it, the purging behavior has probably been present for at least a year and a half to two years. Because ten microns is not that much, the habit can be well-established long before it's actually acknowledged and recognized by a dentist or a dental hygienist. But having said that, once it has been established that an individual is purging often, what can the individual do to protect themselves whether they're getting treatment or if they're choosing not yet to get treatment? Some of the things they can do are, number one, do not brush their teeth immediately after a purge because that's when the damaged dental enamel rods are most fragile, and can be lost. And, once the enamel is lost, it's gone forever. But what they can do to help minimize the enamel loss is rinse their mouth thoroughly with water, and preferably mixed with a little sodium bicarbonate (baking soda),  This will help neutralize the stomach acid in the mouth from the purging event. Delay brushing of the teeth for at least several hours to allow the mouth to reestablish equilibrium, and it is safe to brush the teeth.

If they are practicing purging behavior, the teeth may become sensitive because of the loss of enamel. Their dentist can make them soft custom trays, somewhat like mouth guards (teeth protectors), and give them a prescription for a fluoride-containing gel. Every day in the shower while they're taking a shower and washing their hair, they can put some of this gel in these custom trays, slip them up over the teeth, and let them stay in there for five to ten minutes. At the end of the shower, they remove the tray(s), spit out the remaining gel in the mouth, rinse the trays, and put them away for the next day. So, in other words, they're giving themselves a topical fluoride treatment every day. The one thing we know about fluoride, is it helps stabilize existing enamel and makes it more resistant to decay. Therefore, it encourages remineralization. So that's why having topical fluoride contact on the teeth to prevent tooth structure loss is important. This is especially important if an individual is practicing bulimia-type purging behavior.


What kind of effects might the behavior have on braces, fillings, veneers, or crowns?

Interestingly enough, the acids from the purging do not dissolve these appliances or restorations. But, the tooth structure around these appliances may appear to be “melting” away. That could be a clue to a dentist or dental hygienist to say, "Oh, I'm seeing some changes here that I can't explain." And so, indeed, the appliances themselves wouldn't be affected, but the tooth structure for which they're attached would be.

If the patient is brushing twice daily, rinsing, and taking a multivitamin, will they be able to avoid these dental issues?


They can help minimize it. You are treating the symptoms but you are not treating the underlying cause of the disorder. Rinsing the mouth with water and baking soda as described earlier is appropriate and will help. Certainly, multiple vitamins can be an aid to maintaining nutrition.

Should every pediatric or adult dentist always be able to detect these issues? And what is the standard of care for discussing your findings with the patient and the parents of those under 18 years old?

That is a big one! A dental student and I have recently submitted a paper to a professional journal for publication consideration. The student sent a survey to every dental hygiene program and  dental school  in the United States asking them, "Do you offer educational information to your students on eating disorders?" Not surprisingly, we got a more positive response from dental hygiene programs than we did from dental programs. We speculate that the dental programs which did not offer this to their students may have chosen not to respond to the survey. The ones that did respond were the ones that more often reported that they did include something about eating disorders in their curriculum. So the point is absolutely dentists and dental hygienist programs should be providing learning experiences and teaching how to recognize and to care for patients with either anorexic or bulimic-type behavior. But the truth of the matter, from our national survey, is that less than fifty percent do. And, it just doesn't get the exposure nor does it get the instruction time given to it that it should.

Often when I am speaking to dental hygiene or dental professional groups, I encourage them to have eating disorder patient information literature in their waiting room. I express that even though their patients may not choose to share with them their eating disorder behavior, they may pick up one of those brochures and may reach out for help on their own.  The National Institute of Dental and Cranial Facial Research and other organizations offer free literature and brochures. I'm not telling you anything that you don't already know, but a huge number of young people, and particularly young women, are dying because of eating disorders every year and most of it is being undiagnosed. 

More than forty-plus years ago, I became interested in eating disorders. A young girl had been my dental patient from the time she was three years old to the age of sixteen when she died of the effects of anorexia. When she was three years old, I knew very little about eating disorders. But, in retrospect, it was classic. Her father was a healthcare professional and her mother was an educator. The mother was very petite and dominated any conversation that I would attempt to have with the child. It was just classic if I had known then what I would learn later. But in the end, at sixteen years of age, the patient died as a result of her anorexia.

I've talked to lawyers and it is my understanding that if you believe that the minor patient's behavior is putting them at risk of harming themselves, it is your legal responsibility to engage the parent. Often, the child may initially deny what you suspect. And even if they share it with you, they may say, "But don't tell my parents".  What you then must do is convince them that this is nothing to be ashamed of. This is a social and psychologically based disorder that can best be treated early, and the earlier we intervene the better. Let me talk to your parents, I'm going to be sitting there in the room with you. Nobody's going to blame you. I'm going to put this in the perspective of a health issue and what needs to be done and let them know that we're all a part of a team to help get you the care you need and it is no different than if you have any other medical situation. You need the care and we're going to do it together. But I'm not going to “throw you the wolves” and say it's all your fault. It's not. But the bottom line is we do have the responsibility to engage the parents as soon as possible.

Many adolescent clients struggle with bulimia for years before reaching full recovery. What is your recommendation for oral health treatment during recovery and lifetime maintenance?         

Let me first say, I don't like to use the word cured but rather you have the disorder under control and you are dealing with the damaging behaviors and you're trying to maintain healthy habits. Now, as far as what dental care you can get while you're in the process of overcoming the active phase of bulimia, and particularly the purging, we encourage the dentist not be aggressive in their restorative treatment. Treatment should be conservative, provide preventive care, be supportive until the habit is at least being managed appropriately, and then do the more aggressively necessary dental treatments and restorations. The patient can really do the most at home as described earlier to minimize the damage to the teeth while they are purging. I've talked earlier about washing out the mouth daily with a sodium bicarbonate rinse if they have a purging event, whether it be because of a bulimic-type behavior or just because they're nauseated. Also, having regular topical exposure of fluoride to the teeth will be of great help.


Author: Merrit Elizabeth

Certified Eating Disorder Recovery Coach, CCIEDC 

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