Sir, we read the case report 'The woman who found worms in her mouth' (BDJ 2018; 224: 918), diagnosed as having delusional parasitosis (DP) with interest.

The detailed description of the patient's medical history and examination is indicative of another condition called oral cenesthopathy (OC), characterised by unusual, strange bodily sensations within the oral region without corresponding abnormal extra-intra orofacial findings.1,2

While some patients can clearly describe the sensation as having 'worms', 'fingers', or 'coins' in the mouth, some patients cannot describe this unusual sensation.

Different from the concept of DP that is usually reported by dermatologists, OC is mostly observed in dental clinics, with or without the presence of a dental treatment trigger. Both can be primary or secondary in origin, relating to other mental disorders.

A recent study found the asymmetric regional cerebral blood flow in the broad brain region in OC patients was attenuated following improvement of the symptoms, suggesting that brain dysfunction may be involved in the pathology of OC, especially in the 'primary' origin.3

Many case reports of both conditions described significant effectiveness of antidepressants or antipsychotics on symptom improvement. Instead of arguing which diagnosis is more reasonable, we discuss what a dentist should do to manage patients.

All these patients tried to convince the dentist with their own evidence. Their belief in a dental-related/somatic nature of symptoms made them seek help from a dentist.

In addition, psychiatrists find it difficult to understand the oral complaint. Consequently, a mere psychiatric referral is usually not helpful. In such a situation, explaining and discussing the unknown origin of the symptoms is necessary.

In Japan, in an effort to provide better treatment to patients, dentists and psychiatrists worked together to develop Oral Dyesthesia Rating Scale, a tool to assess psychosomatic symptoms in oral regions.

We suggest that except for patients with mental disorders who need obvious help from a specialist, a collaborative approach between a dentist and psychiatrist should be more actively considered rather than just a direct referral.