title: Fibroblast adhesion and activation onto micro-machined titanium surfaces.
abstract: OBJECTIVE
  Surface modifications performed at the neck of dental implants, in the manner of micro-grooved surfaces, can reduce fibrous tissue encapsulation and prevent bacterial colonization, thereby improving fibrointegration and the formation of a biological seal. However, the applied procedures are technically complex and/or time consuming methods. The aim of this study was to analyse the fibroblast behaviour on modified titanium surfaces obtained, applying a simple and low-cost method.
  
  
  METHODS
  An array of titanium surfaces was obtained using a commercial computerized numerical control lathe, modifying the feed rate and the cutting depth. To elucidate the potential ability of the generated surfaces to activate connective tissue cells, a thorough gene (by real time - qPCR) and protein (by western blot or zymography) expression and cellular response characterization (cell morphology, cell adhesion and cell activation by secreting extracellular matrix (ECM) components and their enzyme regulators) was performed.
  
  
  RESULTS
  Micro-grooved surfaces have statistically significant differences in the groove's width (approximately 10, 50 and 100 μm) depending on the applied advancing fixed speed. Field emission scanning electron microscopy images showed that fibroblasts oriented along the generated grooves, but they were only entirely accommodated on the wider grooves (≥50 μm). Micro-grooved surfaces exhibited an earlier cell attachment and activation, as seen by collagen Iα1 and fibronectin deposition and activation of ECM remodelling enzymes, compared with the other surfaces. However, fibroblasts could remain in an activated state on narrower surfaces (<50 μm) at later stages.
  
  
  CONCLUSIONS
  The use of micro-grooved surfaces could improve implant integration at the gingival site with respect to polished surfaces. Micro-grooved surfaces enhance early fibroblast adhesion and activation, which could be critical for the formation of a biological seal and finally promote tissue integration. Surfaces with wider grooves (≥50 μm) seem to be more appropriate than surfaces with narrow grooves (<50 μm), as fibroblasts could persist in an activated state on narrower grooved surfaces, increasing the probability of producing a fibrotic response.
authors.affiliation: Department of Materials Science, Technical University of Catalonia, Barcelona, Spain. jordi.guillem.marti@upc.edu
authors.forename: J
authors.initials: J
authors.lastname: Guillem-Marti
authors.forename: L
authors.initials: L
authors.lastname: Delgado
authors.forename: M
authors.initials: M
authors.lastname: Godoy-Gallardo
authors.forename: M
authors.initials: M
authors.lastname: Pegueroles
authors.forename: M
authors.initials: M
authors.lastname: Herrero
authors.forename: F J
authors.initials: FJ
authors.lastname: Gil
mesh_terms: D001422:Bacterial Adhesion / Q000502:physiology; D002448:Cell Adhesion / Q000502:physiology; D049109:Cell Proliferation; D048430:Cell Shape / Q000502:physiology; D002478:Cells, Cultured; D060833:Cellular Microenvironment / Q000502:physiology; D024042:Collagen Type I / Q000032:analysis; D000090602:Collagen Type I, alpha 1 Chain; D017076:Computer-Aided Design; D003239:Connective Tissue Cells / Q000502:physiology; D045662:Dental Etching / Q000379:methods*; D003764:Dental Materials / Q000737:chemistry*; D005109:Extracellular Matrix / Q000502:physiology; D005347:Fibroblasts / Q000502:physiology*; D005353:Fibronectins / Q000032:analysis; D051417:Focal Adhesion Kinase 1 / Q000032:analysis; D006801:Humans; D007778:Lactobacillus / Q000502:physiology; D020778:Matrix Metalloproteinase 2 / Q000032:analysis; D020780:Matrix Metalloproteinase 9 / Q000032:analysis; D008855:Microscopy, Electron, Scanning; D013298:Streptococcus sanguis / Q000502:physiology; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*; D016596:Vinculin / Q000032:analysis
chemical_list: D024042:Collagen Type I; D000090602:Collagen Type I, alpha 1 Chain; D003764:Dental Materials; D005353:Fibronectins; C488955:VCL protein, human; D016596:Vinculin; D014025:Titanium; D051417:Focal Adhesion Kinase 1; C496050:PTK2 protein, human; C522361:MMP2 protein, human; D020778:Matrix Metalloproteinase 2; C579270:MMP9 protein, human; D020780:Matrix Metalloproteinase 9