Anaesthetic efficacy of intraoral topical lidocaine and prilocaine in nanostrusctured lipid nanocarriers: a randomized clinical trial

This randomized placebo-controlled crossover trial evaluated if nanostructured lipid nanocarriers (NLC) could improve the topical anaesthetic efficacy of lidocaine and prilocaine (L+P) incorporated in a xanthan-hydrogel applied in the oral cavity. There were no differences among topical formulations regarding the primary endpoints of pain intensity during needle insertion or local anaesthetic injection. Nonetheless, exploratory analyses indicate that individuals with low mechanical pain sensitivity were more susceptible to placebo effects which could also interfere with the anaesthetic effects of the topical formulations. Thus, mechanical pain sensitivity can be an interesting approach to increase assay sensitivity in clinical trials of topical anaesthesia.