Effects of acupuncture at large intestine 4 (LI 4) on electrical tooth pulp stimulation: A randomized controlled pilot study

Background: Research studies have shown acupuncture to have efficacy in the treatment of dental pain, as confirmed by the 1997 NIH Consensus Conference on Acupuncture. Objective: To determine if dry needling acupuncture at Hegu Large Intestine 4 acupoint (LI 4) can reduce the dental pulp sensory threshold produced by electrical pulp stimulation of incisor teeth. Design and Setting: A prospective, randomized placebo-controlled, single-blinded pilot study at the Universidad Mayor (university dental clinic), Santiago, Chile. Participants: A total of 40 healthy adults who had never received acupuncture, who were not receiving anticoagulant medication, nor had any incisor dental restorations. Intervention: Manual stimulation of LI 4 or sham acupuncture with a blunt needle that only touched the skin without penetrating it. Main Outcome Measures: Dental pulp sensory threshold evoked by pulp stimulation. Results: No significant differences in pain reduction were found between the volunteers who received real acupuncture and those who received the placebo intervention. Conclusion: Acupuncture performed at LI 4 did not reduce dental pulp sensory threshold.