OBJECTIVES: Stimulation of acupoint LI4 has been shown to result in analgesic effects in patients experiencing acute pain. We aimed to study the effectiveness of LI4 stimulation for pain relief in children receiving an injection of a local anesthetic (LA). MATERIALS AND METHODS: Children scheduled for dental treatment using LA received bilateral acupuncture at LI4 using indwelling fixed needles. During the treatment, the parents of the patients stimulated the needles by massage. Two different treatment regimes were compared: a standardized LA injection given 5 minutes after acupuncture, and an LA injection without acupuncture. The order of treatment was randomized, with the 2 treatments performed in a crossover manner on different days. Pain intensity during LA injection, assessed by the patient with the Verbal Rating Scale or Faces Pain Scale (0 to 10), was used as the primary endpoint. Parent-assessed and dentist-assessed pain intensity and agitation, heart rate, and the patients' satisfaction with the therapy were also recorded. RESULTS: Data were obtained from 49 patients (22 female; mean age 10 y). Patients reported less pain when acupuncture was used: mean 2.3 (95% confidence interval, 1.5-3.1) versus 3.9 (95% confidence interval, 3.0-4.7); P<0.001. The patients' heart rate remained low throughout the dental treatment after LI4 stimulation, when compared with treatment without acupuncture (P<0.05). LI4 stimulation was safe and increased satisfaction levels in both the patients and their parents, when compared with LA injection alone (P<0.05). DISCUSSION: Stimulation of acupoint LI4 reduces pain and autonomic distress in children during LA injection in dental procedures.