Eating Disorders and Orthodontics UK

Which eating disorders affect orthodontic treatment?

Several eating disorders can have direct or indirect effects on oral health and orthodontic care. Bulimia nervosa involves recurrent purging behaviour, typically self-induced vomiting, which exposes the teeth to repeated acid attack. Anorexia nervosa involves severe caloric restriction and malnutrition that can affect bone density, enamel quality, and healing capacity. ARFID (Avoidant Restrictive Food Intake Disorder) involves highly restricted food intake that may cause nutritional deficiencies relevant to oral health without the purging behaviour of bulimia. Each condition presents differently in the dental context, and clinical management should be tailored to the individual.

How does purging behaviour cause dental erosion?

The most characteristic dental finding associated with purging behaviour is erosion called perimolysis: loss of enamel on the palatal (tongue-side) surfaces of the upper front teeth, while the facial surfaces may be relatively spared because the tongue and cheek shield them during vomiting. Over time this creates a characteristic appearance — upper incisors that look glassy, shorter, and more translucent at the edges, often with scooped-out concavities on the inner surfaces. Dentine hypersensitivity is a common symptom as the protective enamel layer thins. Parotid gland enlargement may also be present in some patients with chronic purging.

How does malnutrition affect orthodontic treatment?

Nutritional deficiencies associated with anorexia and other restrictive eating disorders can affect multiple aspects relevant to orthodontic treatment. Calcium, phosphorus, and vitamin D are essential for bone density and mineralisation — deficiencies can reduce alveolar bone quality and potentially affect how tooth movement occurs. Reduced bone density may also affect the risk of root resorption, a known side effect of orthodontic treatment. Protein deficiency can impair soft tissue healing, relevant when extractions are planned. These risks do not automatically make orthodontic treatment unsafe, but they form part of the clinical picture the orthodontist needs to know about.

When is orthodontic treatment safe to proceed versus defer?

Active purging behaviour creates specific risks for orthodontic treatment. Repeated acid exposure from vomiting attacks enamel and any composite bonding used to hold brackets — it can weaken the bond, increasing the risk of bracket loss. If active purging is ongoing and the patient's eating disorder is not being treated, proceeding with orthodontic treatment requires very careful consideration and usually discussion with the patient's medical team. For patients in recovery or with a stable eating disorder actively managed, orthodontic treatment can often proceed normally with appropriate monitoring.

What is the multidisciplinary approach to eating disorders and orthodontics?

Eating disorders are complex conditions that require medical, psychiatric, and nutritional support. In the UK, specialist eating disorder services are available through CAMHS for younger patients and adult eating disorder teams for those over 18. GP referral is the usual route to these services. The Beat charity (beateatingdisorders.org.uk) provides a helpline at 0808 801 0677, online support groups, and a directory of treatment services. For an orthodontist managing a patient with a known eating disorder, communication with the patient's wider care team — with appropriate consent — is good practice, particularly where treatment decisions are complex.

How do body image concerns interact with orthodontic appliances?

Body image concerns are often central to eating disorders, and orthodontic appliances can interact with these concerns in both positive and negative ways. For some patients, the prospect of improved dental appearance and smile aesthetics is a positive motivator and a meaningful part of improving self-image. For others, the visible nature of fixed braces or the discomfort of wearing appliances may add to existing distress, particularly during active phases of illness. Clear aligners are sometimes preferred by patients with appearance concerns, though they require high compliance. Clinicians should discuss these considerations sensitively with patients and, where relevant, with their carers or clinical team.

What confidentiality and safeguarding rules apply?

Dental professionals in the UK have both ethical obligations and safeguarding responsibilities. For adult patients, confidentiality applies and information should not be shared without consent except where there is a risk to the patient that overrides confidentiality — a high bar. For patients under 18, safeguarding considerations apply and clinicians should follow their practice's child protection policy. The GDC Standards make clear that patient welfare is the primary consideration. If an orthodontist suspects a patient is being harmed through an eating disorder where a child is at risk, appropriate referral pathways exist and must be followed.

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This guide is for general information only. It is not a diagnosis, treatment plan, or substitute for advice from a registered dentist or orthodontist.