Mixed bacterial biofilm effects on corrosion kinetics in alloys of Ticp-G4 with different surface treatment

• Grant number: 17/11471-5
• Support Opportunities: Scholarships in Brazil - Master
• Start date: September 01, 2017
• End date: February 28, 2019
• Field of knowledge: Health Sciences - Dentistry - Dental Materials
• Principal Investigator: Wirley Goncalves Assuncao
• Grantee: Jadison Junio Conforte
• 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, in vitro, the kinetics of corrosion in different surfaces of Ticp-G4 (Ti) alloys (machined and textured by means of double acid attack) as a function of the bacterial biofilm effect. For this purpose, 28 Ticp-G4 (Ti) discs randomly divided according to the surface (n = 14) in Group I (machined surface) and Group II (textured surface by double acid attack) will be used. After the metallography process on all Ticp-G4 (Ti) discs, for microbiological analysis, they will be positioned in 12-well plates containing Enterococcus faecalis culture and incubated for 168 hours (7 days) at 37°C, With changes of means every 2 days. After the biofilm adesion period, part of the specimens (10 discs, being 5 of each group) will be allocated to the electrochemical test using Electrochemical Impedance Spectroscopy (EIS). The corrosion current density (Icorr), passivation current density (IPASS), corrosion potential (Ecorr), capacitance (Cdl) and polarization resistance (Rp) of the Ti oxide layer will be determined. After the corrosion analysis, surface characterization analysis will be carried out by atomic force microscopy (AFM) and scanning electron microscopy (SEM and EED). Another 18 Ti disks (9 of each group) will be used for evaluation for bacterial cell count of the biofilm collected from the surface of Ti disks. For the quantitative parameters, a test of normality and homoscedasticity will be initially applied to verify the distribution of the data in the normal curve. Thereafter, the most appropriate tests, parametric or nonparametric, will be elected, considering a 5% significance level. We hypothesize that biofilm will be formed in the greatest amount on the surface of double acid etching treated Ti, and that the presence of biofilm will decrease the corrosion resistance of Ticp, proportionally to the amount of biofilm formed. (AU)

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

CONFORTE, Jadison Junio. Effect of Enterococcus faecalis biofilm on corrosion resistance in titanium submitted to different surface treatments. 2019. Master's Dissertation - Universidade Estadual Paulista (Unesp). Faculdade de Odontologia. Araçatuba Araçatuba.