title: Microbial adhesion on novel yttria-stabilized tetragonal zirconia (Y-TZP) implant surfaces with nitrogen-doped hydrogenated amorphous carbon (a-C:H:N) coatings.
abstract: OBJECTIVE
  Biomaterial surfaces are at high risk for initial microbial colonization, persistence, and concomitant infection. The rationale of this study was to assess the initial adhesion on novel implant surfaces of Enterococcus faecalis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans upon incubation.
  
  
  METHODS
  The tested samples were 3 mol% yttria-stabilized tetragonal zirconia polycrystal (3Y-TZP) samples with nitrogen-doped hydrogenated amorphous carbon (a-C:H:N) coating (A) and 3Y-TZP samples coated with ceria-stabilized zirconia-based (Ce-TZP) composite and a-C:H:N (B). Uncoated 3Y-TZP samples (C) and bovine enamel slabs (BES) served as controls. Once the surface was characterized, the adherent microorganisms were quantified by estimating the colony-forming units (CFUs). Microbial vitality was assessed by live/dead staining, and microbial-biomaterial surface topography was visualized by scanning electron microscopy (SEM).
  
  
  RESULTS
  Overall, A and B presented the lowest CFU values for all microorganisms, while C sheltered significantly less E. faecalis, P. aeruginosa, and C. albicans than BES. Compared to the controls, B demonstrated the lowest vitality values for E. coli (54.12 %) and C. albicans (67.99 %). Interestingly, A (29.24 %) exhibited higher eradication rates for S. aureus than B (13.95 %).
  
  
  CONCLUSIONS
  Within the limitations of this study, a-C:H:N-coated 3Y-TZP surfaces tended to harbor less initially adherent microorganisms and selectively interfered with their vitality.
  
  
  CONCLUSIONS
  This could enable further investigation of the new multi-functional zirconia surfaces to confirm their favorable antimicrobial properties in vivo.
authors.affiliation: Department of Operative Dentistry and Periodontology, Center for Dental Medicine, Albert Ludwigs University, Hugstetter Strasse 55, 79106, Freiburg, Germany.
authors.forename: Stefanie
authors.initials: S
authors.lastname: Schienle
authors.affiliation: Department of Operative Dentistry and Periodontology, Center for Dental Medicine, Albert Ludwigs University, Hugstetter Strasse 55, 79106, Freiburg, Germany.
authors.forename: Ali
authors.initials: A
authors.lastname: Al-Ahmad
authors.affiliation: Division of Prosthodontics, Department of Dental Medicine, Oral and Maxillofacial Surgery, Medical Center, University of Freiburg, Hugstetter Str. 55, 79106, Freiburg, Germany.
authors.forename: Ralf Joachim
authors.initials: RJ
authors.lastname: Kohal
authors.affiliation: NTTF Coatings GmbH, Maarweg 32, 53619, Rheinbreitbach, Germany.
authors.forename: Falk
authors.initials: F
authors.lastname: Bernsmann
authors.affiliation: Swerea IVF AB, Argongatan 30, 43153, Mölndal, Sweden.
authors.forename: Erik
authors.initials: E
authors.lastname: Adolfsson
authors.affiliation: Politecnico di Torino, Department of Applied Science and Technology, INSTM RU Politecnico di Torino, LINCE Lab, Corso Duca degli Abruzzi, Turin, Italy.
authors.forename: Laura
authors.initials: L
authors.lastname: Montanaro
authors.affiliation: Politecnico di Torino, Department of Applied Science and Technology, INSTM RU Politecnico di Torino, LINCE Lab, Corso Duca degli Abruzzi, Turin, Italy.
authors.forename: Paola
authors.initials: P
authors.lastname: Palmero
authors.affiliation: DOCERAM Medical Ceramics GmbH, Hesslingsweg 65-67, 44309, Dortmund, Germany.
authors.forename: Tobias
authors.initials: T
authors.lastname: Fürderer
authors.affiliation: Université de Lyon, INSA-Lyon MATEIS UMR CNRS 5510, Bât. Blaise Pascal 7 Av. Jean Capelle, 69621, Villeurbanne, France.
authors.forename: Jérôme
authors.initials: J
authors.lastname: Chevalier
authors.affiliation: Department of Operative Dentistry and Periodontology, Center for Dental Medicine, Albert Ludwigs University, Hugstetter Strasse 55, 79106, Freiburg, Germany.
authors.forename: Elmar
authors.initials: E
authors.lastname: Hellwig
authors.affiliation: Department of Operative Dentistry and Periodontology, Center for Dental Medicine, Albert Ludwigs University, Hugstetter Strasse 55, 79106, Freiburg, Germany. lamprini.karygianni@uniklinik-freiburg.de.
authors.forename: Lamprini
authors.initials: L
authors.lastname: Karygianni
mesh_terms: D000818:Animals; D001422:Bacterial Adhesion; D002176:Candida albicans; D002244:Carbon / Q000737:chemistry; D002417:Cattle; D020099:Coated Materials, Biocompatible / Q000737:chemistry*; D003764:Dental Materials / Q000737:chemistry*; D013293:Enterococcus faecalis; D004926:Escherichia coli; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D009584:Nitrogen / Q000737:chemistry; D011550:Pseudomonas aeruginosa; D013194:Staining and Labeling; D013211:Staphylococcus aureus; D013234:Stem Cells; D015019:Yttrium / Q000737:chemistry; D015040:Zirconium / Q000737:chemistry
chemical_list: D020099:Coated Materials, Biocompatible; D003764:Dental Materials; D015019:Yttrium; D002244:Carbon; D015040:Zirconium; D009584:Nitrogen; C028541:zirconium oxide; C091417:yttria
keywords: 3 mol% yttria-stabilized tetragonal zirconia polycrystal (3Y-TZP); Colony-forming units (CFUs); Initial microbial adhesion; Live/dead staining; Nitrogen-doped hydrogenated amorphous carbon (a-C:H:N)