Evaluation of prilocaine for the reduction of pain associated with transmucosal anesthetic administration.

This investigation evaluated the use and efficacy of prilocaine HCl (4% plain Citanest) for minimizing pain associated with the intraoral administration of local anesthesia. Clinical anecdotes support the hypothesis that prilocaine without a vasoconstrictor reduces pain during injection. To determine relative injection discomfort, use of 4% plain prilocaine was compared with use of 2% lidocaine with 1:100,000 epinephrine and 2% mepivacaine with 1:20,000 levonordefrin. Prior to routine endodontic procedures, 150 adult patients received 0.3 to 1.8 mL of local anesthetic via the same gauge needle without the use of a topical local anesthetic. Injection methods included buccal infiltration, labial infiltration, palatal infiltration, and inferior alveolar nerve block. Following each injection, patients were asked to describe the level of discomfort by scoring on a visual analog scale of 1 to 10, where 1 = painless and 10 = severe pain. Analyses via 2-way analysis of variance revealed no interaction between anesthetic and site of injection. However, there were statistically significant differences among the injection sites. Post hoc analysis revealed that prilocaine was associated with significantly less pain perception when compared to mepivacaine and lidocaine. These results suggest that differences in initial pain perception during transmucosal injection may be a function of the local anesthetic use, and prilocaine can produce less discomfort than the others tested.