Comparison between Topical and Injection Anesthetics on Pain Related to Orthodontic Miniscrew Placement: A Split-mouth Study

Abstract

The aims of this study were to compare the anesthetic effect of a lidocaine/prilocaine (L/P) topical anesthetic with placebo on pain from needle sticks and to compare the anesthetic effect of the L/P topical anesthetic with an infiltrative anesthetic on pain from orthodontic miniscrew placement. Pain elimination was analyzed from two interventions: (a) needle stick and (b) miniscrew insertion. When assessing pain from needle stick, one side of the mandible received 2.5% lidocaine/2.5% prilocaine topical anesthetic, and the other side received placebo. When evaluating pain from miniscrew placement, one side of the mandible received L/P topical anesthetic and the other side received infiltrative anesthetic. The findings were recorded on a Visual Analogue Scale after needle stick and after miniscrew placement. Subjective assessment was analyzed by a questionnaire. The L/P topical anesthetic significantly eliminated the pain from needle stick (Mann-Whitney test of medians, 29.0 vs 0.0, respectively, p<0.001). However, the injection anesthetic eliminated the pain from the miniscrew placement better than the L/P topical anesthetic (Mann-Whitney test of medians, 0.0 vs 5.5, respectively, p<0.001). Eighty percent of the subjects felt more comfortable with L/P topical anesthetic than injection anesthetic. Pain from needle stick pain was reported to be the most uncomfortable part of the study. The L/P topical anesthetic efficiently eliminated pain from needle stick. The L/P topical anesthetic did not completely eliminate pain from miniscrew placement as the injection anesthesia, but it did reduce pain to tolerable levels. L/P topical anesthetics can significantly eliminate pain from needle stick injections, and L/P topical anesthetics can reduce pain from orthodontic miniscrew placement to tolerable levels.