RESUMEN
INTRODUCTION: When patients express fear and anxiety about dentistry, 1 main source involves the administration of local anesthetic. The Dentapen (Septodont, Lancaster, PA) is a computer-controlled local anesthetic device that regulates the rate of anesthetic deposition to reduce pain associated with dental injections. The purpose of this study was to evaluate differences in perceived pain during the administration of local anesthesia of the maxillary lateral incisors using the ramp-up and continuous injection modes of the Dentapen. METHODS: This study used a randomized, controlled, double-blind, crossover, experimental design. The investigators randomly assigned the order of the teeth (#7 or #10) and the 2 delivery modes (continuous or ramp-up). Participants completed a Corah dental anxiety scale at each visit and were injected on 2 separate visits at least 2 weeks apart. After each injection, participants rated their perceived pain using a Heft-Parker visual analog scale at needle insertion, needle placement, and solution deposition. Repeated measures analysis of variance was used to determine differences in perceived pain between the 2 modes. RESULTS: The data from 116 participants were analyzed. The perceived pain at deposition with the ramp-up mode (mean = 51.98, standard deviation = 30.04) was less than the continuous mode (mean = 59.98, standard deviation = 36.28) although not statistically significant (F1230 = 2.569, P > .05). Clinically, the perceived pain with the ramp-up mode was in the mild range (<54 mm), whereas the mean perceived pain with the continuous mode was in the moderate/severe range (>54 mm). CONCLUSIONS: Further research should evaluate whether the ramp-up mode could be used to reduce the pain perceived with other dental injections.