Local Anesthesia: History; Potential Toxicity; Clinical Investigation of Mepivacaine

Abstract

Two double-blind clinical investigations of mepivacaine were conducted at the College of Dentistry, Ohio State University. The first study compared 2 per cent aqueous mepivacaine, 3 per cent aqueous mepivacaine, commercially available 2 per cent mepivacaine with 1:20,000 l-nordefrin, and the commercial Ravocaine solution (2 per cent procaine, 0.4 per cent propoxycaine, 1:20,000 1-nordefrin). Approximately 80 inferior alveolar nerve blocks, zygomatic nerve blocks or anterior maxillary infiltrations were made with each of the four solutions. The results appear in Table 1. Owing to the excellent results obtained with 3 per cent aqueous mepivacaine, a second study was made comparing the commercial 2 per cent mepivacaine with 1:20,000 l-nordefrin with another experimental solution containing 2½ per cent mepivacaine with 1:40,000 l-nordefrin. The data from this study indicate that these two solutions were very similar in effect except that the duration of the experimental solution was shorter owing to a smaller concentration of vasoconstrictor. The results of approximately 80 inferior alveolar nerve blocks, zygomatic nerve blocks or anterior maxillary infiltrations of each solution are tabulated in the last two columns of Table 1.