Abstract
We read with great interest the recent exchange regarding the diagnostic framework for burning mouth syndrome (BMS) in Cephalalgia Reports, specifically the initial proposal by Suga et al., 1 the insightful commentary by Musella et al. 2 and the subsequent reply by Suga et al. 3 We commend these initiatives to broaden the classification of idiopathic orofacial pain conditions. Our clinical experience strongly aligns with the perspective advocated by Musella et al., 2 supporting the need to move beyond a narrow “burning” criterion and embrace a more comprehensive concept such as orofacial dysthesias and perceptual disorders (ODPD).
In our practice, we have encountered numerous patients whose presentations underscore the limitations of current rigid diagnostic criteria, particularly concerning symptom onset and temporal patterns. We have observed a significant cohort of individuals who develop instantaneous and identical oral symptoms (e.g. burning, dysesthesia, dysgeusia, foreign body sensation, xerostomia) immediately following a specific “exposure” in the oral cavity. From our experience, these exposures frequently occur in a sexual context, such as ejaculation into the mouth or cunnilingus, or are triggered by intense anxiety related to potential sexually transmitted infections (STIs) after possible exposure. Similarly, unexpected exposure to chemicals has also been identified as a direct precipitant for immediate symptom onset. The swift, often dramatic, appearance of these symptoms, frequently in the absence of objective pathological findings, suggests a powerful psychogenic component. Our observations are also in line with the experience of cenestopathies, where bodily sensations are perceived as bizarre or alien, further highlighting the perceptual distortions involved.
Furthermore, our observations indicate that these symptoms are not always constant throughout the day. Many patients report that their oral discomfort is intermittent, often negligible or non-existent when they are concentrated, distracted or engaged in work, only to resurface when their attention is free such as before falling asleep. This fluctuating nature, while common in psychosomatic presentations, is not adequately captured by current diagnostic requirements that typically stipulate a “daily” or “chronic” presence for a minimum duration (e.g. over two hours and for more than three months).
While the demographic profile of patients presenting with these immediate-type BMS or ODPD symptoms may differ from those with classical BMS, our experience suggests that they may respond to the same treatment protocols for BMS, probably with the same challenging efficacy of treating classical BMS.
We have also observed combined expression with “restless mouth syndrome” and we believe that this should be included as part of the broader spectrum of expression for ODPD. 4
Accordingly, we respectfully suggest that future revisions of the classification in ICHD-4 and ICOP for BMS or ODPD explicitly consider:
Instantaneous Onset: Symptoms should not be required to have a minimum duration (e.g. three months) if a clear, precipitating event is identified such as a sexual act that has conscious or subconscious conflict attached to or is otherwise psychologically significant. The immediate, post-exposure onset of symptoms should be a recognized presentation. Intermittent Presentation: The diagnostic criteria should accommodate symptoms that are intermittent throughout the day, particularly those influenced by attention, concentration or distraction, and those exacerbating before falling asleep. Location: The location of symptoms should also include the vermilion (lip border), not solely restricting the classification to the oral mucosa. Broader Symptom Expression: The classification should encompass presentations such as restless mouth syndrome as part of ODPD.
Incorporating these considerations into a broader ODPD framework would enhance diagnostic precision, improve clinical phenotyping, and ultimately lead to more tailored and effective therapeutic strategies for a patient population currently underserved by overly restrictive definitions.
