In vitro evaluation of the protective potential of the association of statherin derived peptide with different concentrations of sodium trimethaphosphate against intrinsic initial dental erosion

• Grant number: 23/14457-4
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: January 01, 2024
• End date: December 02, 2025
• Field of knowledge: Health Sciences - Dentistry
• Principal Investigator: Marília Afonso Rabelo Buzalaf
• Grantee: Hannah Zomignan Barros
• Host Institution: Faculdade de Odontologia de Bauru (FOB). Universidade de São Paulo (USP). Bauru , SP, Brazil
• Associated research grant: 19/26070-1 - Modulation of acquired enamel pellicle to control dental mineral loss: unravelling mechanisms to make therapies possible, AP.TEM

Abstract

Sodium trimetaphosphate (TMP) has a high enamel adsorption capacity, reducing its solubility, and it also exhibits a strong tendency to form complexes with cations due to the presence of a phosphate group in the TMP molecular structure. Through "acquired pellicle engineering" proteins such as hemoglobin is incorporated into acquired enamel pellicle (AEP) to enhance its acid-resistant capacity and protective role against dental erosion. Therefore, associating hemoglobin with TMP may have a synergistic effect on protection. The objective of this study is evaluating the protective effect of hemoglobin associated with TMP against initial enamel erosion in vitro. 102 bovine enamel samples (4 x 4 mm) will be prepared. Subsequently, the samples will be randomized and divided into 6 groups for in vitro experimental, according to the treatments (n/group=17): 1) Deionized water (negative control); 2) Commercial solution with SnCl2/NaF/AmF (800 ppm Sn+2, 500 ppm F-, pH 4.5, Erosion Protection® - GABA, (positive control); 3) Statherin-derived peptide 1.88 × 10- 5 million; 4) Statherin-derived peptide 1.88 × 10-5 M + 0.5% TMP; 5) Statherin-derived peptide 1.88 × 10-5 M + 1.0% TMP; 6) Statherin Derived Peptide 1.88 × 10-5 M + 3.0% TMP. Initially, the samples will be individually treated (250 µL) with the respective solutions for 2 h at 37° C under constant agitation. Then, AEP will be individually formed (250 µL) for 2 h at 37° C under constant agitation (stimulated saliva will be collected from 9 volunteers). Subsequently, the erosive challenge will be performed individually (1 mL) with hydrochloric acid (0.01 M, for 10 s, at 37° C under constant agitation). These procedures will be carried out once a day for 3 consecutive days. Surface microhardness (SHM) analyses will be performed, and changes in SHM (baseline SHM - post-erosion SHM) will be calculated. In addition, enamel surface reflection intensity analyzes will be performed. The data will be analyzed using GraphPad Prism software. First, the data will be checked for normality (Kolmogorov-Smirnov test) and homogeneity (Bartlett's test) to select the appropriate statistical test. The significance level will be set at 5%.