Reversing the Effects of 2% Lidocaine

Dental procedures often require the use of local anesthesia. The effects of the anesthesia usually linger for some time after the dental procedure is completed which can lead to discomfort and occasionally injury from lip/tongue biting. Clinical trials have shown phentolamine mesylate (OraVerse) to be effective at reducing the amount of time to reversal of local anesthesia compared to sham injections. However, no trials have been conducted comparing phentolamine mesylate to a true control injection. Such trials are needed in order to definitively show that it is the phentolamine mesylate itself that is causing the reduction in anesthesia rather than a dilution effect. The objective of the proposed research is to conduct a pilot-scale randomized clinical trial evaluating the difference in time required to the return of normal soft-tissue sensation and function in participants who had received an inferior alveolar nerve block (using 2% Lidocaine 1:100,000 epinephrine), followed by an injection with either 1) OraVerse (phentolamine mesylate) or 2) sterile physiological water (control). The study population will comprise dentistry and dental hygiene students of the second year classes at Dalhousie University, Halifax, NS, Canada. This study population has been chosen because these students usually practice dental anesthesia on each other as a part of a course on local anesthesia. This proposed pilot scale study will be a double-blind controlled trial using parallel groups. As part of their usual anaesthesia course, the dental and dental hygiene students will be practicing their inferior alveolar nerve injections on one another using 2% Lidocaine 1:100,000 epinephrine. Students who decide to participate in the study will be randomly assigned to one of two groups: Group 1 will receive an injection of OraVerse (treatment group), while Group 2 will receive an injection of sterile physiological water (control group). The time required to the return of soft-tissue sensatio