Background: Acupuncture is increasingly being used by the general population and investigated by conventional medicine; however, studies of its effects on pain still lack adequate control procedures.
Objectives: To evaluate the (1) efficacy of Chinese acupuncture in treating postoperative oral surgery pain, (2) validity of a placebo-controlled procedure, and (3) effects of psychological factors on outcomes.
Design: Randomized, double-blind, placebo-controlled trial.
Setting: Dental School Outpatient Clinic, University of Maryland at Baltimore.
Participants: Thirty-nine healthy subjects, aged 18 to 40 years, assigned to treatment (n=19) and control (n=20) groups.
Main outcome measures: Patients' self-reports of time until moderate pain, time until medication use, total pain relief, pain half gone, and total pain medication consumption.
Results: Mean pain-free postoperative time was significantly longer in the acupuncture group (172.9 minutes) than in the placebo group (93.8 minutes) (P=.01), as was time until moderate pain (P=.008). Mean number of minutes before requesting pain rescue medication was significantly longer in the treatment group (242.1 minutes) than in the placebo group (166.2 minutes) (P=.01), as was time until medication use (P=.01). Average pain medication consumption was significantly less in the treatment group (1.1 tablets) than in the placebo group (1.65 tablets) (P=.05). There were no significant between-groups differences on total-pain-relief scores or pain-half-gone scores (P>.05). Nearly half or more of all patients were uncertain of or incorrect about their group assignment. Outcomes were not associated with psychological factors in multivariate models.
Conclusions: Acupuncture is superior to the placebo in preventing postoperative dental pain; noninsertion placebo procedure is valid as a control.