Effect of acupuncture on pain threshold measurement of tooth pulp in the monkey.

The effect of acupuncture on pain threshold from tooth pulp stimulation was studied in alert, awake monkeys. Manual manipulation of acupuncture needles in specific acupuncture points in the hands and legs caused a consistent and significant rise in threshold. Some points, such as Ho-Ku (LI-4) and Tsu-San-Li (St-36), produced more prominent analgesic effects than others. Increase of pain threshold was observed also after application of finger pressure on acupuncture points. Acupuncture and finger pressure applied to certain muscle points exhibited similar analgesic effects.