Major depressive disorder. Psychopathology, medical management and dental implications

Major depressive disorder, or MDD, is a psychiatric illness in which mood, thoughts and behavioral patterns are impaired for long periods. The illness distresses the person and impairs his or her social functioning and quality of life. MDD is characterized by marked sadness or a loss of interest or pleasure in daily activities, and is accompanied by weight change, sleep disturbance, fatigue, difficulty concentrating, physical impairment and a high suicide rate. In 2000, the World Health Organization, or WHO, identified MDD as the fourth ranked cause of disability and premature death in the world. WHO projected that by 2020, MDD would rise in disease burden to be second only to ischemic heart disease. The disorder is common in the United States, with a lifetime prevalence rate of 17 percent and a recurrence rate of more than 50 percent.

MDD may be associated with extensive dental disease, and people may seek dental treatment before becoming aware of their psychiatric illness. MDD frequently is associated with a disinterest in performing appropriate oral hygiene techniques, a cariogenic diet, diminished salivary flow, rampant dental caries, advanced periodontal disease and oral dysesthesias. Many medications used to treat the disease magnify the xerostomia and increase the incidence of dental disease. Appropriate dental management requires a vigorous dental education program, the use of saliva substitutes and anticaries agents containing fluoride, and special precautions when prescribing or administering analgesics and local anesthetics.

Dentists cognizant of these signs and symptoms have an opportunity to recognize patients with occult MDD. After confirmation of the diagnosis and institution of treatment by a mental health practitioner, dentists usually can provide a full range of services that may enhance patients' self-esteem and contribute to the psychotherapeutic aspect of management.