Recurrent aphthous stomatitis -episodic mouth ulcers (RAS; aphthae; canker sores)

Recurrent Aphthous Stomatitis (RAS) is a prevalent oral mucosal condition that often presents as a clinical enigma in primary care settings. Notably affecting individuals who are generally in good health, RAS is characterized by periodic episodes of painful, well-demarcated oral ulcers. The lesions can significantly impact the quality of life, causing pain and discomfort during basic activities such as speaking, eating, and swallowing. Given its recurrent nature, this condition can be particularly frustrating for both clinicians and patients, thus necessitating a robust understanding for effective management.

Despite the commonality of this ailment, which manifests across age groups but predominantly in childhood and adolescence, it is crucial to distinguish it from other causes of oral ulceration. Numerous conditions like Behçet's syndrome, Crohn's disease, and PFAPA syndrome, among others, can manifest with aphthous-like ulceration. Therefore, RAS is a diagnosis of exclusion, made after ruling out systemic disease that might present with similar oral symptoms.

This comprehensive overview aims to delve into the clinical characteristics, aetiology, and pathogenesis of RAS, along with providing guidance on its differential diagnosis and treatment options. The information is intended for clinicians working in primary care settings, where most of these cases are initially present, and aims to...