EPIDEMIOLOGY OF TEMPOROMANDIBULAR DISORDERS - IMPLICATIONS FOR THE INVESTIGATION OF ETIOLOGIC FACTORS

Epidemiology is the study of the distribution, determinants, and natur al history of disease in populations. Epidemiology has several uses in addition to its traditional role of documenting the public health sig nificance of a condition. Notably, epidemiologic methods and data can be used to identify and verify causes of disease. This article reviews the epidemiologic data on pain in the temporomandibular region, and o n signs and symptoms associated with specific subtypes of temporomandi bular disorders, with the aim of identifying possible etiologic factor s for these conditions that deserve further study. Despite methodologi c and population differences, several consistencies are apparent in th e epidemiologic literature. Pain in the temporomandibular region appea rs to be relatively common, occurring in approximately 10% of the popu lation over age 18: it is primarily a condition of young and middle-ag ed adults, rather than of children or the elderly, and is approximatel y twice as common in women as in men. This prevalence pattern suggests that etiologic investigations should be directed at biologic and psyc hosocial factors that are more common in women than in men, and dimini sh in older age groups. Most signs and symptoms associated with partic ular temporomandibular disorders (e.g., joint sounds, pain in the join t) also appear to be more prevalent in women than in men, although age patterns for these signs and symptoms are not as clear as for temporo mandibular pain. The available data highlight the need for further res earch on etiologic factors associated with temporomandibular pain and with specific diagnostic subtypes of temporomandibular disorders.