ABSTRACT
This chapter describes the most common facial pain conditions that general practitioners and dentists encounter in their clinic. Facial pain is encountered by a high percentage of the population and has special biological, emotional, and psychological meaning to the patient because of the special role of the orofacial region in vital functions, such as chewing, swallowing, talking, and expression of emotions. Temporomandibular disorders (TMD) are not a single entity but rather a cluster of related pain conditions in the masticatory muscles, temporomandibular joint (TMJ), and associated structures, that is, an orofacial musculoskeletal pain condition. A nonhierarchical classification scheme based on operationalized and systematic criteria has been developed and extensively tested for reliability and validity. Epidemiological studies have indicated that between 3 and 15 percent of the population will qualify for a TMD pain diagnosis. Few studies have tried to separate TMJ pain from myofascial TMD pain, but the latter appears to be less prevalent than the former.
