Corrosive, microstructural and peri-implant osteogenesis behavior of Ti-15Zr and commercial alloys (Ticp and Ti-6Al-4V) with or without surface treatment: an in vitro and in vivo study

• Grant number: 13/15545-2
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: October 01, 2013
• End date: May 11, 2016
• Field of knowledge: Health Sciences - Dentistry - Oral and Maxillofacial Surgery
• Principal Investigator: Wirley Goncalves Assuncao
• Grantee: Leonardo Perez Faverani
• Host Institution: Faculdade de Odontologia (FOA). Universidade Estadual Paulista (UNESP). Campus de Araçatuba. Araçatuba , SP, Brazil

Abstract

The aim of this study will be to evaluate the corrosive behavior of Ti-Zr alloy and the peri-implant osteogenesis of dental implants, with or without surface treatment, through an in vitro and in vivo analysis. The hypothesis to be tested is that the surface treatment (double acid etching) and the test alloy (Ti-15Zr) will create a pattern of corrosion different from those observed on machined-surface and other alloys tested (cpTi and Ti-6Al-4V). Regarding the in vitro analysis, it is suspected that the Ti-15Zr, cpTi and Ti-6Al-4V alloys with surface treatment will show greater values of bone interface contact (BIC) and area of new bone formation at the region of implant first threads (AB). For electrochemical test (n=3) 36 discs of cpTi, Ti-6Al-4V and Ti-15Zr will be fabricate and submitted to pattern tests as open circuit potential, electrochemical impedance spectroscopy (EIS) and potenciodynamic tests will be conducted in simulated body fluid (SBF) or artificial saliva. The corrosion current density (Icorr), the passivation current density (Ipass), corrosion potential (Ecorr), capacitance (Cdl) and polarization resistance (Rq) of Ti oxide layer will be determined. The surface of the discs will be characterized by scanning electron microscope (SEM), white-light interferometry, energy dispersive spectroscope (EDS) and Vickers hardness. The energy dispersive spectroscope (EDS) will evaluate the composition of oxides created on the Ti surface. For in vivo analysis, 135 male rabbits will be used and 270 implants of cpTi, Ti-6Al-4V and Ti-15Zr inserted, being one implant for each rabbits' tibia, with both machined and treated surfaces. The animals will be submitted to euthanasia at 15, 30 and 60 days after surgery. The histomorphometric (BIC and AB), the biomechanical (reverse torque) and also the immunohistochemistry analysis will be performed with antibodies of osteopontin, osteocalcin (OC), RANKL, collagen type 1 and osteoprotegerin (OPG). The data will be submitted to the appropriated statistical analysis with 5% of significance. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

CORDEIRO, JAIRO M.; FAVERANI, LEONARDO P.; GRANDINI, CARLOS R.; RANGEL, ELIDIANE C.; DA CRUZ, NILSON C.; NOCITI JUNIOR, FRANCISCO H.; ALMEIDA, AMANDA B.; VICENTE, FABIO B.; MORAIS, BRUNA R. G.; BARAO, VALENTIM A. R.; et al. Characterization of chemically treated Ti-Zr system alloys for dental implant application. Materials Science & Engineering C-Materials for Biological Applications, v. 92, p. 849-861, NOV 1 2018. (13/08451-1, 16/11470-6, 15/03159-6, 13/15545-2, 15/25562-7, 14/23575-1)