Temporomandibular disorders constitute a set of related clinical conditions whose most important clinical feature is persistent pain in the masticatory muscles and/or the temporomandibular joint, which is often associated with limitations in mandibular function. For some patients, the clinical condition represents a transient problem that resolves or responds readily to conservative, noninvasive treatments with minimal impact on overall well-being. In marked contrast, TMD, for others, comes to represent what Bonica has called a malefic force an intense and persistent pain condition that has a debilitating impact on every aspect of the patients physical, mental and emotional life. Despite decades of intense scientific research and clinical attention, etiologies remain elusive. Explanations have ranged from occlusal pathology to pernicious oral habits to depression. Equally enigmatic have been attempts to develop evidence-based rationales for the myriad of treatments available, which, again, range from occlusal therapy and orthodontics to surgery, appliances, medications and psychotherapy. The current presentation suggests that the biopsychosocial model remains the best approach to gaining an understanding of how to integrate the host of biologic, clinical and behavioral factors including life-span, gender and hormonal factors that may account for the onset, maintenance and remission of TMD, as well as for understanding how to make rationale choices for treatment. Epidemiologic, basic and clinical scientific data, including exciting findings from genetics and our present ability to image the pain-involved brain, may offer perspectives on how best to understand the potential role that such diverse factors as occlusion (still very much an unproven factor in TMD), local anatomy and physiology, and even central brain processing of thinking and emotions could possibly have, if any, in the highly varied ways in which different patients express their TMD condition.
Evaluate the relationship of TMD to aspects of concern to orthodontics
Apply current concepts relating to chronic pain and TMD as a chronic pain condition when assessing and diagnosing patients with chronic orofacial pain
Acquire a broader perspective with regard to present and future understanding about pain experience, which requires integrating such diverse factors as genes, gender, learning, memory, emotion and the central processes that integrate all these factors to yield potential new diagnostic and therapeutic pain approaches