Xylocaine: 50 years of clinical service to dentistry.

In today's dental practice, local anesthesia is safe and effective, and injectable agents only rarely cause allergy. Ester-type agents, like procaine, which served the profession for over 50 years, have now been abandoned and are no longer available in dental cartridges in the U.S. Modern practitioners know of their disadvantages only through historical accounts of local anesthesia, and utilize daily the excellent chemical and pharmacologic characteristics of the amide local anesthetics, a tradition begun with the introduction of Xylocaine in the late 1940s and a tradition which will likely continue into the 21st century. The reader is referred to Table III for a comparison of quantities and dollar-value of sales of amide local anesthetics available in dental cartridges (17). In order to supplant Xylocaine (lidocaine) as a preferred local anesthetic in dentistry, any new agent will have to prove that it is superior in terms of short onset, appropriate duration, stability, excellent safety record, low allergenicity, and topical efficacy. As our understanding of the molecular structure of ion channels and the interactions of local anesthetics with neural sodium channels increase, new agents can be developed rationally. In the meantime, the amide local anesthetics will continue to serve dentists and their patients by providing safe and effective control of pain to facilitate ever-advancing surgical and restorative techniques.