Iontophoresis of lidocaine for topical anesthesia

Iontophoresis , also called "common ion transfer" utilizes direct current to induce the transfer of an ion across a body surface. The process was orginally introduced by Luuc at the beginning of the 20th-century. Since that time there have been numerous reports of the ionphoresis of medications for widely varying disorders. Ionphoresis of idocaine with epinephrine induced excellent anesthesia of the tympanic membrane. In dental work, iontophoresis of local anesthetic agents has been used for tooth extraction and treatment of infected tooth root canals. Gangarosa reported minimal patient discomfort during tooth extraction using ionphoresis for deep surface anesthesia. He proposed that this procedure could eliminate a fear of hypodermic injections and therefore promote a better patient-dentist relationship. Sisler also utilized ionphoresis for local anesthesia. He found anesthesia of the conjunctiva by this method effective for surgery of the conjunctiva, subconjuctiva and superficial tarsus. This study was undertaken to compare the duration and depth of anesthesia produced by lidocaine and physiologic saline when administered by ionphoresis, subcutaneous infiltration and topical application.