Functionalized surface for titanium dental implants obtained by tantalum and zirconium sputtering: analysis of antibacterial activity, cellular viability, surface characterization, and tribochemical degradation.

• Grant number: 24/02830-5
• Support Opportunities: Scholarships in Brazil - Master
• Effective date (Start): July 01, 2024
• Effective date (End): August 31, 2025
• Field of knowledge: Health Sciences - Dentistry - Dental Materials
• Principal Investigator: Rodrigo Galo
• Grantee: Renan Leonardi de Oliveira Rigotti
• Host Institution: Faculdade de Odontologia de Ribeirão Preto (FORP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

Functionalization of titanium and its alloys aims to improve antibacterial and pro-osteogenic properties, as well as enabling resistance to tribochemical degradation. Thus, this study aims to develop a cathodic spray coating of tantalum (Ta) and zirconium (Zr) on commercially pure titanium (Ti-Cp) substrates. For this purpose, Ti-Cp discs (Ø13.0x2.0mm) will be fabricated and divided into: G1=Ti-Cp; G2=Ti-Cp/Ta; G3=Ti-Cp/Zr. This project will have 3 outcomes: 1) Development of the functionalized surface; 2) Microbiological and biological assessments to verify the colonization capacity of S. mutans on the experimental surfaces through Colony Forming Units (CFU) and viability of VERO-CCL-81 cells using the resazurin assay; 3) Electrochemical, tribochemical, physical, chemical, and mechanical characterization through anodic polarization tests at potential values ranging from -500mV to 2000mV, with a scan rate of 1 mVs-1, and electrochemical impedance spectroscopy (EIS). Tribochemical tests will be performed using a linear brushing machine. Soft-bristled toothbrushes will be used as the counter body, brushing for 244 hours with a load of 200N, inserted in an open circuit potential system, divided into groups (n=5): distilled water (A), fluoride-free toothpaste (SF), and fluoride toothpaste (F). Surface characterization will be conducted by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), atomic force microscopy (AFM), X-ray diffraction (XRD), roughness, wettability, staining, Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and microhardness. Data will be analyzed using homogeneity tests, and if the sample shows normal distribution, parametric tests will be used; otherwise, non-parametric tests will be employed.