Sputtered crystalline TiO2 film drives improved surface properties of titanium-based biomedical implants

Heloisa Navarro Pantaroto; Jairo Matozinho Cordeiro; Lucas Toniolo Pereira; Amanda Bandeira de Almeida; Francisco Humberto Nociti Junior; Elidiane Cipriano Rangel; Nilton Francelosi Azevedo Neto; Jose Humberto Dias da Silva; Valentim Adelino Ricardo Barão

doi:10.1016/j.msec.2020.111638

Sputtered crystalline TiO₂ film drives improved surface properties of titanium-based biomedical implants

Mater Sci Eng C Mater Biol Appl. 2021 Feb:119:111638. doi: 10.1016/j.msec.2020.111638. Epub 2020 Oct 17.

Authors

Heloisa Navarro Pantaroto¹, Jairo Matozinho Cordeiro², Lucas Toniolo Pereira¹, Amanda Bandeira de Almeida¹, Francisco Humberto Nociti Junior¹, Elidiane Cipriano Rangel³, Nilton Francelosi Azevedo Neto⁴, Jose Humberto Dias da Silva⁴, Valentim Adelino Ricardo Barão⁵

Affiliations

¹ University of Campinas (UNICAMP), Piracicaba Dental School, Department of Prosthodontics and Periodontics, Av. Limeira, 901, Piracicaba, São Paulo 13414-903, Brazil.
² University of Campinas (UNICAMP), Piracicaba Dental School, Department of Prosthodontics and Periodontics, Av. Limeira, 901, Piracicaba, São Paulo 13414-903, Brazil; Institute of Biomaterials, Tribocorrosion and Nanomedicine (IBTN), Brazil.
³ São Paulo State University (UNESP), Institute of Science and Technology, Av. Três de Março, 511, Sorocaba, São Paulo, 18087-180, Brazil.
⁴ São Paulo State University (UNESP), Department of Physics, Av. Eng. Luís Edmundo C. Coube, 14-01, Bauru, São Paulo 17033-360, Brazil.
⁵ University of Campinas (UNICAMP), Piracicaba Dental School, Department of Prosthodontics and Periodontics, Av. Limeira, 901, Piracicaba, São Paulo 13414-903, Brazil; Institute of Biomaterials, Tribocorrosion and Nanomedicine (IBTN), Brazil. Electronic address: vbarao@unicamp.br.

PMID: 33321676
DOI: 10.1016/j.msec.2020.111638

Abstract

Different crystalline phases in sputtered TiO₂ films were tailored to determine their surface and electrochemical properties, protein adsorption and apatite layer formation on titanium-based implant material. Deposition conditions of two TiO₂ crystalline phases (anatase and rutile) were established and then grown on commercially pure titanium (cpTi) by magnetron sputtering to obtain the following groups: A-TiO₂ (anatase), M-TiO₂ (anatase and rutile mixture), R-TiO₂ (rutile). Non-treated commercially pure titanium (cpTi) was used as a control. Surfaces characterization included: chemical composition, topography, crystalline phase and surface free energy (SFE). Electrochemical tests were conducted using simulated body fluid (SBF). Albumin adsorption was measured by bicinchoninic acid method. Hydroxyapatite (HA) precipitation was evaluated after 28 days of immersion in SBF. MC3T3-E1 cell adhesion, morphology and spreading onto the experimental surfaces were evaluated by scanning electron microscopy. Sputtering treatment modified cpTi topography by increasing its surface roughness. CpTi and M-TiO₂ groups presented the greatest SFE. In general, TiO₂ films displayed improved electrochemical behavior compared to cpTi, with M-TiO₂ featuring the highest polarization resistance. Rutile phase exhibited a greater influence on decreasing the current density and corrosion rate, while the presence of a bi-phasic polycrystalline condition displayed a more stable passive behavior. M-TiO₂ featured increased albumin adsorption. HA morphology was dependent on the crystalline phase, being more evident in the bi-phasic group. Furthermore, M-TiO₂ displayed normal cell adhesion and morphology. The combination of anatase and rutile structures to generate TiO₂ films is a promising strategy to improve biomedical implants properties including greater corrosion protection, higher protein adsorption, bioactivity and non-cytotoxicity effect.

Keywords: Blood proteins; Corrosion; Dental implants; Hydroxyapatites; Magnetron sputtering; Titanium.

MeSH terms

Microscopy, Electron, Scanning
Prostheses and Implants*
Surface Properties
Titanium*
X-Ray Diffraction

Substances

titanium dioxide
Titanium