Efficacy of 1% ropivacaine gel for topical anesthesia of human oral mucosa

Objective: To evaluate the efficacy of 1% ropivacaine for topical anesthesia in dentistry. Method and Materials: Thirty healthy volunteers randomly (blind crossover) received the following treatments: 20 mg of 1% ropivacaine gel (ropivacaine-20), 60 mg of 1% ropivacaine gel (ropivacaine-60), 20 mg of the eutectic mixture of local anesthetics 2.5% lidocaine and 2.5% prilocaine (EMLA cream, AstraZeneca; EMLA-20), 60 mg of EMLA (EMLA-60), 20 mg of 20% benzocaine gel (Benzotop, DFL; benzocaine-20), and 60 mg of 20% benzocaine gel (benzocaine-60), applied on the maxillary buccal fold of the right canine at different sessions. Pain was assessed by visual analog scale (VAS) and 11-point box scale (BS-11) after the insertion of 30-gauge needles. Soft tissue anesthesia was measured by pinprick test. Data were analyzed by Friedman and Pearson correlation tests. Results: All the topical anesthetics evaluated showed similar performance in relation to the pain perceived after needle insertion (P > .05), and there were no significant differences among groups considering VAS or BS-11 (P = .177 and P = .179, respectively). The duration of soft tissue anesthesia was not statistically significantly different for ropivacaine-20, EMLA-20, benzocaine-20, ropivacaine-60, EMLA-60, and benzocaine-60, but EMLA-60 showed significantly longer duration than the other agents (P .05). Conclusion: All topical anesthetics were similar in reducing pain to needle insertion. EMLA-60 promoted longer duration of soft tissue anesthesia. Keywords: benzocaine, eutectic mixture of lidocaine and prilocaine, local anesthesia, oral mucosa, ropivacaine, topical anesthesia, topical anesthetic