Dental management of the myasthenic patient.

Myasthenia gravis (MG) is an auto-immune disorder of neuromuscular transmission which results in weakness and fatigue of skeletal muscles. The defect in neuromuscular transmission is most commonly seen in the muscles of the eyes, face, neck and shoulders but, in some patients, the respiratory muscles are involved. Patients with this condition may present with problems that necessitate special consideration when managing their dental treatment. Patients who are only mildly affected by MG can be treated in general dental practice for routine care. There are no contra-indications to the use of local anaesthetic agents and the presence of a vasoconstrictor is desirable. More severely affected patients and those who are very anxious about dental treatment should be cared for within the hospital environment. In these patients, respiratory muscles may be affected and, as a result, a myasthenic crisis may arise which requires assisted ventilation and, in some cases, intubation. Those patients who are fearful of the dental environment are likely to be emotionally stressed during such times and this increases the risk of a myasthenic crisis; sedation techniques can be beneficial in this group of patients.