Drug delivery systems for dental topical anesthesia: in vitro and in vivo assays

• Grant number: 20/03786-9
• Support Opportunities: Regular Research Grants
• Start date: March 01, 2021
• End date: February 29, 2024
• Field of knowledge: Health Sciences - Dentistry
• Principal Investigator: Michelle Franz Montan Braga Leite
• Grantee: Michelle Franz Montan Braga Leite
• Host Institution: Faculdade de Odontologia de Piracicaba (FOP). Universidade Estadual de Campinas (UNICAMP). Piracicaba , SP, Brazil
• Associated researchers: Marlus Chorilli ; Yuri Martins Costa

Abstract

Local anesthesia (LA) is necessary to perform most dental procedures. However, although essential, LA is much feared by patients with needle phobia, which can harm the oral health of those who avoid dental treatment for this reason. Thus, topical anesthesia is performed long before LA to reduce the discomfort of the injection. In addition, it can also be used to perform small procedures on soft tissues, such as removing primary teeth, periodontal scraping and removing small lesions. However, many studies show that commercial topical anesthetics fail to promote deep anesthesia satisfactory duration. One of the main reasons for this failure is due to the efficiency of the epithelium that lines the oral mucosa in hindering the penetration of substances, such as agents anesthetics. In this context, our research group has been looking for tools for the development of nanostructured drug delivery systems that increase the permeation of anesthetics in order to develop an effective topical anesthetic. Objectives: This proposal aims to continue the research group's projects with in vitro and in vivo studies, with a focus on developing an effective delivery system for topical anesthesia in the oral mucosa. Specific objectives: to develop, characterize and evaluate the toxicity and anesthetic efficacy of lidocaine (LDC) and epinephrine (EPI) co-incorporated in a nanostructured drug delivery system, called mucoadhesive liquid crystal precursor system (LCPS) as a strategy to improve topical anesthesia in the oral cavity. Methodology: LCPS consisting of ethoxylated 20 and propoxylated 5 cetyl alcohol, oleic acid and chitosan containing LDC and EPI co-incorporated will be prepared and characterized by polarized light microscopy, low-angle X-ray scattering, gelation test in contact with artificial saliva, rheology tests, in vitro mucoadhesion test, texture profile analysis, swelling tests, in vitro release and permeation tests and stability. Subsequently, LCPS toxicity will be investigated using the in vivo model of the chicken embryo chorioallantoic membrane (CAM). Expected results: to develop an effective and biocompatible nanostructured topical anesthetic formulation potentially a candidate for future clinical studies. In this context, this project aims to contribute to the evolution of topical anesthesia in Dentistry. (AU)