A prospective, randomized single-blind study of the anesthetic efficacy of frequency-dependent conduction blockade of the inferior alveolar nerve.

The purpose of this prospective, randomized single-blind study was to evaluate the degree of pulpal anesthesia obtained with frequency-dependent conduction blockade of the inferior alveolar nerve (IAN). Eighty adult volunteers randomly received two IAN blocks: an IAN block followed by continuous electrical stimulation for 3 minutes of the first molar or lateral incisor for six cycles over a time period of 64 minutes; an IAN block followed by mock electrical stimulation using the same cycles. The IAN blocks were administered at two separate appointments spaced at least 1 week apart in a crossover design. An electric pulp tester was used to test for anesthesia of the first molar and lateral incisor. Anesthesia was considered successful when two consecutive 80 readings were obtained within 15 minutes, and the 80 reading was recorded through the 60th minute. The anesthetic success rate for the stimulated IAN block was 35% and 48% for the lateral incisor and first molar, respectively. For the mock stimulated IAN, success was 18% for the lateral incisor and 62% for the first molar. There was no significant difference between the two IAN block techniques. We concluded that the stimulation of nerves in the presence of local anesthesia (frequency-dependent nerve block) did not statistically increase the success rate of pulpal anesthesia for an IAN block. Copyright © 2011 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.