Background – Major Depressive Disorder (MDD/depression) is a mental illness characterized by marked sadness, and/or a loss of interest or pleasure in daily activities may be accompanied by weight loss, sleep disturbance, difficulty concentrating, and a high suicide rate. The disorder is very common in Canada with a lifetime prevalence rate of approximately 24%. Unfortunately, half of all patients with depression never see a physician and therefore go undiagnosed and untreated. Clinical Implications – Individuals under treatment for depression and those whose illness has not been diagnosed often present to the dentist with significant oral disease. Dentists need to be cognizant of how to safely and compassionately provide care to those already receiving mental health services. They must also be familiar with the psychiatric symptoms of the disorder so that they can effectuate a timely referral to a physician of those with occult or relapsing disease. Depression is frequently associated with a disinterest in performing oral hygiene, a cariogenic diet, rampant dental decay, advanced periodontal disease, and oral dysesthesias. Antidepressants used to treat the disease cause the xerostomia and may increase the severity of dental disease. Appropriate dental management necessitates a vigorous preventive dental education program, the use of artificial salivary products, antiseptic mouthwash, daily fluoride mouth rinse, and special precautions when administering local anesthetics with vasoconstrictors and prescribing analgesics. Conclusions — Dentists invoking appropriate precautions can usually provide a full range of services to individuals with major depressive disorder thereby enhancing patient self esteem and contributing to the therapeutic milieu.