Pilot Randomized Clinical Trial Study: Comparative Study of 10% Lidocaine Hydrochloride Solution with Lidocaine Prilocaine Emulsion Prior to Local Anesthetic Injection

The pain caused by the injection of local anesthetic has been reported as one of the main complaints of dental patients. Topical anesthetics are widely used drugs in dentistry, mainly to control pain associated with the needle penetration in the administration of local anesthesia.

The present study aimed to evaluate (5%,7.5% and 10%) concentrations of lidocaine/prilocaine agent, compared to the common 10% lidocaine hydrochloride spray in the oral cavity.

This was a split-mouth double-blind, randomized clinical trial pilot study. We randomized 15 patients, ages 35 to 64 years, with American Society of Anesthesiologists I and II with severe chronic periodontitis who were referred to the dental clinic for surgery, to receive 4 topical anesthetics (5%, 7.5%, and 10%) lidocaine prilocaine emulsion and 10% lidocaine hydrochloride topical anesthetic agent before local infiltration. Primary outcomes were assessing drug safety and pain level that measured by assessment of visual analog scale (VAS) scores of pain during LA injection in the first premolar and second molar in each maxillary quadrant in 15 patients corresponding to the posterior superior alveolar nerve (PSA) and secondary outcome was the relationship between age and gender regarding pain perception, and a total of 60 regions were analyzed.

Results revealed that there was no statistically significant difference between lidocaine hydrochloride and (5%,7.5% and 10%) lidocaine prilocaine in terms of pain reduction when the 4 different compounds were compared. According to Spearman's rank correlation coefficient and Friedman test, the age and gender of the patients had an insignificant correlation with the anesthetic effects of the four studied solutions.

Based on these results, age and gender have insignificant effects on the pain scores and it can be said that the four solutions do not have significant differences regarding their anesthetic effects; also, we did not find any adverse reactions by using 7.5% and 10% lidocaine/prilocaine agent.