title: Determinants of biofilm formation and cleanability of titanium surfaces.
abstract: OBJECTIVE
  The aim of the present study was to analyze biofilm formation on four different titanium-based surfaces (machined titanium zirconium (TiZr) alloy, M; machined, acid-etched TiZr alloy, modMA; machined, sandblasted, acid-etched TiZr alloy, modSLA; and micro-grooved titanium aluminum vanadium alloy, TAV MG) in an experimental human model.
  
  
  METHODS
  Custom-made discs were mounted in individual intraoral splint housings and worn by 16 volunteers for 24 h. The safranin staining assay, isothermal microcalorimetry (IMC), and SEM were applied before and after surface cleaning.
  
  
  RESULTS
  The hydrophilic surfaces modMA and modSLA with greater surface micro-roughness exhibited significantly more biofilm than the hydrophobic surfaces TAV MG and M. The standardized cleaning procedure substantially reduced the biofilm mass on all surfaces. After cleaning, the IMC analyses demonstrated a longer lag time of the growth curve on TAV MG compared to modSLA. Inter- and intraindividual variations in biofilm formation on the titanium discs were evident throughout the study.
  
  
  CONCLUSIONS
  Surface hydrophilicity and roughness enhanced biofilm formation in vivo, whereas surface topography was the most influential factor that determined surface cleanability. While the grooved surface retained larger amounts of initial biofilm, the machined surface was easier to clean, but proliferation indicated by increased metabolic activity (growth rate) in IMC occurred despite mechanical biofilm removal.
authors.affiliation: Department of Periodontology, Endodontology and Cariology, University Center for Dental Medicine, University of Basel, Basel, Switzerland.
authors.forename: Lucia K
authors.initials: LK
authors.lastname: Zaugg
authors.affiliation: Clinic for Preventive Dentistry and Oral Microbiology, University Center for Dental Medicine, University of Basel, Basel, Switzerland.
authors.forename: Monika
authors.initials: M
authors.lastname: Astasov-Frauenhoffer
authors.affiliation: Center of Biomechanics & Biocalorimetry, University of Basel, Allschwil, Switzerland.|Department of Urology, University Hospital Basel, Basel, Switzerland.
authors.forename: Olivier
authors.initials: O
authors.lastname: Braissant
authors.affiliation: Clinic for Preventive Dentistry and Oral Microbiology, University Center for Dental Medicine, University of Basel, Basel, Switzerland.
authors.forename: Irmgard
authors.initials: I
authors.lastname: Hauser-Gerspach
authors.affiliation: Clinic for Preventive Dentistry and Oral Microbiology, University Center for Dental Medicine, University of Basel, Basel, Switzerland.
authors.forename: Tuomas
authors.initials: T
authors.lastname: Waltimo
authors.affiliation: Department of Periodontology, Endodontology and Cariology, University Center for Dental Medicine, University of Basel, Basel, Switzerland.
authors.forename: Nicola U
authors.initials: NU
authors.lastname: Zitzmann
mesh_terms: D000328:Adult; D000368:Aged; D000540:Alveolar Ridge Augmentation; D018441:Biofilms; D015921:Dental Implants; D019232:Dental Restoration Failure; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000175:diagnosis*; D012307:Risk Factors; D013499:Surface Properties; D014025:Titanium; D016896:Treatment Outcome
chemical_list: D015921:Dental Implants; D014025:Titanium
keywords: biofilm formation; dental implants; isothermal microcalorimetry; surface hydrophilicity; surface roughness