Use of N2O/O2/enflurane anesthesia for dental treatment of the handicapped. To develop an anesthesia maintenance method that could be expected to maintain a reasonably stable state during dental treatment of the handicapped, three methods (N2O/O2 [0% enflurane (E), n = 12], N2O/O2/0.6% E [n = 8], N2O/O2/1.5% E [n = 7]) were evaluated in terms of changes in plasma levels of cortisol, epinephrine (EP), and norepinephrine (NE). During a treatment period of 60 minutes, cortisol levels increased in the 0% E group (from 9.5 +/- 1.8 micrograms/dL to 19.4 +/- 2.4 micrograms/dL, P less than .01), did not change in 0.6% E group, and decreased in 1.5% E group (from 9.3 +/- 1.7 micrograms/dL to 5.8 +/- 1.0 micrograms/dL, P less than .01). Epinephrine and NE levels increased in the 0% E group, but were suppressed in the 0.6% E and 1.5% E groups. It is suggested that N2O/O2 inhalation anesthesia supplemented with low-dose enflurane produces a stable state during dental treatment with respect to cortisol, EP, and NE responses. 