title: Inflammatory cytokine release is affected by surface morphology and chemistry of titanium implants.
abstract: To investigate in vitro cellular cytokine expression in relation to commercially pure titanium discs, comparing a native surface to a fluorinated oxide nanotube surface. Control samples pure titanium discs with a homogenous wave of the margins and grooves and an often smeared-out surface structure. Test samples pure titanium discs with a fluorinated titanium oxide chemistry and surface morphology with nanopore/tube geometry characterized by ordered structures of nanotubes with a diameter of ≈ 120 nm, a spacing of ≈ 30 nm, and a wall thickness of ≈ 10 nm. Cross-section view showed vertically aligned nanotubes with similar lengths of ≈ 700 nm. Peripheral blood mononuclear leucocytes were cultured for 1, 3, and 6 days according to standard procedures. BioPlex Pro™ assays were used for analysis and detection of cytokines. Selected inflammatory cytokines are reported. A pronounced difference in production of the inflammatogenic cytokines was observed. Leucocytes exposed to control coins produced significantly more TNF-α, IL-1ß, and IL-6 than the test nanotube coins. The effect on the TH2 cytokine IL-4 was less pronounced at day 6 compared to days 1 and 3, and slightly higher expressed on the control coins. The morphology and surface chemistry of the titanium surface have a profound impact on basic cytokine production in vitro. Within the limitations of the present study, it seems that the fluorinated oxide nanotube surface results in a lower inflammatory response compared to a rather flat surface that seems to favour inflammation.
authors.affiliation: Department of Oral Microbiology and Immunology, The Sahlgrenska Academy, Institute of Odontology, University of Gothenburg, P.O. Box 450, 405 30, Göteborg, Sweden.
authors.forename: Anna-Karin
authors.initials: AK
authors.lastname: Östberg
authors.forename: Ulf
authors.initials: U
authors.lastname: Dahlgren
authors.forename: Young-Taeg
authors.initials: YT
authors.lastname: Sul
authors.forename: Carina B
authors.initials: CB
authors.lastname: Johansson
mesh_terms: D002478:Cells, Cultured; D016207:Cytokines / Q000276:immunology*; D006801:Humans; D007249:Inflammation / Q000209:etiology / Q000276:immunology*; D007963:Leukocytes, Mononuclear / Q000187:drug effects / Q000276:immunology*; D008422:Materials Testing; D043942:Nanotubes / Q000737:chemistry / Q000633:toxicity* / Q000648:ultrastructure; D019736:Prostheses and Implants / Q000009:adverse effects*; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry / Q000633:toxicity*
chemical_list: D016207:Cytokines; C009495:titanium dioxide; D014025:Titanium