title: Micro-arc oxidation as a tool to develop multifunctional calcium-rich surfaces for dental implant applications.
abstract: Titanium (Ti) is commonly used in dental implant applications. Surface modification strategies are being followed in last years in order to build Ti oxide-based surfaces that can fulfill, simultaneously, the following requirements: induced cell attachment and adhesion, while providing a superior corrosion and tribocorrosion performance. In this work micro-arc oxidation (MAO) was used as a tool for the growth of a nanostructured bioactive titanium oxide layer aimed to enhance cell attachment and adhesion for dental implant applications. Characterization of the surfaces was performed, in terms of morphology, topography, chemical composition and crystalline structure. Primary human osteoblast adhesion on the developed surfaces was investigated in detail by electronic and atomic force microscopy as well as immunocytochemistry. Also an investigation on the early cytokine production was performed. Results show that a relatively thick hybrid and graded oxide layer was produced on the Ti surface, being constituted by a mixture of anatase, rutile and amorphous phases where calcium (Ca) and phosphorous (P) were incorporated. An outermost nanometric-thick amorphous oxide layer rich in Ca was present in the film. This amorphous layer, rich in Ca, improved fibroblast viability and metabolic activity as well as osteoblast adhesion. High-resolution techniques allowed to understand that osteoblasts adhered less in the crystalline-rich regions while they preferentially adhere and spread over in the Ca-rich amorphous oxide layer. Also, these surfaces induce higher amounts of IFN-γ cytokine secretion, which is known to regulate inflammatory responses, bone microarchitecture as well as cytoskeleton reorganization and cellular spreading. These surfaces are promising in the context of dental implants, since they might lead to faster osseointegration.
authors.affiliation: Department of Periodontology, Araraquara Dental School, University Estadual Paulista, Rua Humaitá 1680, 14801-903 Araraquara, São Paulo, Brazil; Directory of Metrology Applied to Life Science, National Institute of Metrology Quality and Technology, Av. N. S. das Graças 50, Xerém, Duque de Caxias, Rio de Janeiro, Brazil; Brazilian Branch of Institute of Biomaterials, Tribocorrosion and Nanomedicine (IBTN/Br), Brazil. Electronic address: arribeiro@inmetro.gov.br.
authors.forename: A R
authors.initials: AR
authors.lastname: Ribeiro
authors.affiliation: Brazilian Branch of Institute of Biomaterials, Tribocorrosion and Nanomedicine (IBTN/Br), Brazil; Centre for Mechanical and Materials Technologies, University of Minho, Campus de Azurém, 4800-058 Guimarães, Portugal. Electronic address: fernando@dem.uminho.pt.
authors.forename: F
authors.initials: F
authors.lastname: Oliveira
authors.affiliation: Directory of Metrology Applied to Life Science, National Institute of Metrology Quality and Technology, Av. N. S. das Graças 50, Xerém, Duque de Caxias, Rio de Janeiro, Brazil. Electronic address: lcboldrini@inmetro.gov.br.
authors.forename: L C
authors.initials: LC
authors.lastname: Boldrini
authors.affiliation: Directory of Metrology Applied to Life Science, National Institute of Metrology Quality and Technology, Av. N. S. das Graças 50, Xerém, Duque de Caxias, Rio de Janeiro, Brazil. Electronic address: leitepec@gmail.com.
authors.forename: P E
authors.initials: PE
authors.lastname: Leite
authors.affiliation: Directory of Metrology Applied to Life Science, National Institute of Metrology Quality and Technology, Av. N. S. das Graças 50, Xerém, Duque de Caxias, Rio de Janeiro, Brazil. Electronic address: prifalagan@gmail.com.
authors.forename: P
authors.initials: P
authors.lastname: Falagan-Lotsch
authors.affiliation: Clinical Research Unit, Antonio Pedro Hospital, Fluminense Federal University, Niterói, Brazil. Electronic address: adrianalinhares@hotmail.com.
authors.forename: A B R
authors.initials: AB
authors.lastname: Linhares
authors.affiliation: Brazilian Branch of Institute of Biomaterials, Tribocorrosion and Nanomedicine (IBTN/Br), Brazil; Departamento de Química e Bioquímica, Universidade Estadual Paulista - UNESP, Distrito de Rubião Junior S/N, 18618-970 Botucatu, São Paulo, Brazil. Electronic address: wzambuzzi@gmail.com.
authors.forename: W F
authors.initials: WF
authors.lastname: Zambuzzi
authors.affiliation: Physics Department, Federal University of Juiz de Fora (UFJF), Rua José Lourenço Kelmer, 36036-900 Minas Gerais, Brazil. Electronic address: bfragneaud@fisica.ufjf.br.
authors.forename: B
authors.initials: B
authors.lastname: Fragneaud
authors.affiliation: Metrology Materials Division, National Institute of Metrology Quality and Technology, Av. N. S. das Graças 50, Xerém, Duque de Caxias, Rio de Janeiro, Brazil. Electronic address: apcampos@inmetro.gov.br.
authors.forename: A P C
authors.initials: AP
authors.lastname: Campos
authors.affiliation: Metrology Materials Division, National Institute of Metrology Quality and Technology, Av. N. S. das Graças 50, Xerém, Duque de Caxias, Rio de Janeiro, Brazil. Electronic address: cpgouvea@inmetro.gov.br.
authors.forename: C P
authors.initials: CP
authors.lastname: Gouvêa
authors.affiliation: Metrology Materials Division, National Institute of Metrology Quality and Technology, Av. N. S. das Graças 50, Xerém, Duque de Caxias, Rio de Janeiro, Brazil. Electronic address: bsarchanjo@inmetro.gov.br.
authors.forename: B S
authors.initials: BS
authors.lastname: Archanjo
authors.affiliation: Metrology Materials Division, National Institute of Metrology Quality and Technology, Av. N. S. das Graças 50, Xerém, Duque de Caxias, Rio de Janeiro, Brazil. Electronic address: caachete@inmetro.gov.br.
authors.forename: C A
authors.initials: CA
authors.lastname: Achete
authors.affiliation: Department of Periodontology, Araraquara Dental School, University Estadual Paulista, Rua Humaitá 1680, 14801-903 Araraquara, São Paulo, Brazil. Electronic address: junior.elcio@gmail.com.
authors.forename: E
authors.initials: E
authors.lastname: Marcantonio
authors.affiliation: Brazilian Branch of Institute of Biomaterials, Tribocorrosion and Nanomedicine (IBTN/Br), Brazil; Departamento de Física, Universidade Estadual Paulista - UNESP, Av. Eng. Luiz Edmundo Carrijo Coube, 14-01 Bauru, São Paulo, Brazil. Electronic address: lrocha@dem.uminho.pt.
authors.forename: L A
authors.initials: LA
authors.lastname: Rocha
authors.affiliation: Directory of Metrology Applied to Life Science, National Institute of Metrology Quality and Technology, Av. N. S. das Graças 50, Xerém, Duque de Caxias, Rio de Janeiro, Brazil; Brazilian Branch of Institute of Biomaterials, Tribocorrosion and Nanomedicine (IBTN/Br), Brazil; Dental School, Fluminense Federal University, Niterói, Brazil. Electronic address: jmgranjeiro@inmetro.gov.br.
authors.forename: J M
authors.initials: JM
authors.lastname: Granjeiro
mesh_terms: D002118:Calcium / Q000737:chemistry*; D002448:Cell Adhesion; D002478:Cells, Cultured; D020099:Coated Materials, Biocompatible / Q000737:chemistry; D016207:Cytokines / Q000378:metabolism; D015921:Dental Implants; D006801:Humans; D007150:Immunohistochemistry; D008855:Microscopy, Electron, Scanning; D049329:Nanostructures / Q000737:chemistry; D016348:Osseointegration; D010006:Osteoblasts / Q000166:cytology / Q000378:metabolism; D047495:PPAR gamma / Q000235:genetics / Q000378:metabolism; D010758:Phosphorus / Q000737:chemistry; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry; D014746:Vimentin / Q000235:genetics / Q000378:metabolism
chemical_list: D020099:Coated Materials, Biocompatible; D016207:Cytokines; D015921:Dental Implants; D047495:PPAR gamma; D014746:Vimentin; C009495:titanium dioxide; D010758:Phosphorus; D014025:Titanium; D002118:Calcium
keywords: Adhesion; Biointerphase; Calcium; Human bone-derived cells; Micro-arc-oxidation; Phosphorus; Titanium