Evaluation of the surface free energy of enamel treated with CaneCPI-5, Stn15pSpS or Hb, isolated or combined, associated or not with EGCG

• Grant number: 25/03667-3
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: May 01, 2025
• End date: April 30, 2026
• Field of knowledge: Health Sciences - Dentistry
• Principal Investigator: Marília Afonso Rabelo Buzalaf
• Grantee: Ana Luiza Oliveira Guerra
• Host Institution: Faculdade de Odontologia de Bauru (FOB). Universidade de São Paulo (USP). Bauru , SP, Brazil

Abstract

In recent years, our research group has been using proteomic strategies to identify candidate proteins for enamel protection against erosive demineralization. Among these, sugarcane-derived cystatin (CaneCPI-5), statherin-derived peptide (StN15) and human hemoglobin (Hb) appear to be promising.In addition, polyphenols such as EGCG have the ability to readily adsorb to the acquired enamel pellicle (AEP), making it rougher, thicker and more electron-dense, increasing the precipitation of protective proteins such as albumin, statherin and cystatins. Therefore, in this project we intend to answer the following question: Does the treatment of the enamel surface with CaneCPI-5, Stn15pSpS or Hb, alone or in combination, associated or not with EGCG, alter the surface free energy of the enamel? To answer this question, an in vitro study will be carried out, in which one hundred blocks of bovine dental enamel (4 × 4 mm) will be prepared and divided into 10 groups, according to each treatment. The analyses will be performed in an automated goniometer, using 3 probing liquids: diiodomethane, water and ethylene glycol. After treatment, the blocks will be dried with air for 45 min, in order to stabilize the formed pellicle. Next, 0.5 ¿L of each liquid will be dispensed onto the surface of each block and the contact angles will be measured using the images captured by a CCD camera. Different parameters of the surface free energy (mN/m), such as acid (g+, acceptor component), base (g-, donor component) and Lifshiz van der Waals (gLW, nonpolar component) will be calculated using the van Oss, Chaudhery and Good model to determine the surface free energy. (AU)