The classification and differential diagnosis of orofacial pain

There are currently four main pain classification systems relevant to orofacial pain (OFP): the International Association for the Study of Pain, International Classification of Headache Disorders, the American Academy of Orofacial Pain and the Research Diagnostic Criteria for Temporomandibular Disorders. Of the four, the Research Diagnostic Criteria for Temporomandibular Disorders is the most biopsychosocial system, with the remaining three focusing more on the biomedical aspects. Unsurprisingly, clinical scientists and clinicians have both reported perceived deficiencies in the published systems and have proposed further modified classifications and nomenclature for OFP. Establishing a standardized biopsychosocial classification of OFP is essential for ensuring continuity for patient care since it creates a standardized language with which to communicate healthcare information, thus enabling improved and more specific (epidemiological) research and patient care. Despite ongoing attempts, an accepted overarching classification of OFP is still a work in progress. There is an urgent need for a robust classification system for OFP. This review aims to highlight the recent debate and continued struggle to attain a consensus on a classification of OFP and highlight some recent developments that assist differential diagnosis of these conditions.