Sphincteric and sensory components of anal continence were investigated before and after restorative proctocolectomy and three loop ileal reservoir. Bowel habit, appearance of small intestinal mucosa, resting tone, squeeze pressure, anal canal length, pouch capacity and ileal sensation were investigated in 50 patients. The physiologic, endoscopic and histologic patterns were related to the occurrence of functional disturbances. The pressures in the anal canal as measured by manometry were found to be within the range of normality. The length of the sphincter was 3.4 +/- 0.6 centimeters; the maximal capacity of the reservoir was 450 +/- 204 milliliters of air. An ileorectoanal inhibitory reflex was recorded postoperatively in 52 per cent of the patients and normal postoperative continence was observed in 86 per cent of the patients, with no instances of gross incontinence. According to the results of the present study, the anatomic rearrangement that occurs after this surgical procedure preserved a satisfactory continence due to the integrity of the anal sphincters; minor leakage rarely occurred and was mainly related to a long inflamed distal portion of the ileum requiring self catheterization after operations for colitis. The best results were obtained in patients with polyposis who neither had staged procedures nor preoperative steroids.