title: Effect of nitride film coatings on cell compatibility.
abstract: OBJECTIVE
  To evaluate the cytotoxicity of nickel-based alloy surfaces after nitride film coatings.
  
  
  METHODS
  A total of 120 disc-shaped specimens (1.5 x 12.0mm) were prepared from nickel (Ni) alloy ingots and metallurgically ground with silicon carbide (SiC) sandpaper to 1200 grit and used as the ground group. Ninety specimens from the ground group were selected and further polished with 1.0 microm aluminum powder slurry and assigned as the polished group. Titanium nitride (TiN) and titanium-aluminum nitride (TiAlN) film coatings were deposited onto 30 polished specimens each by a reactive radio frequency magnetron sputter deposition system and used as coated groups, respectively. The morphological changes and cytoskeleton of tested human gingival fibroblasts were observed using fluorescence microscopy at 3h and 24h time periods, respectively. An MTT assay was used to assess cell viability at 24h. The results were statistically analyzed (n=5, ANOVA, Scheffe', p<0.05).
  
  
  RESULTS
  After 3h of incubation, cells began to spread on the test surfaces. Spindle-shaped fibroblasts with well-developed cytoskeleton and distinct actin fibers were observed at the 24h incubation point on the polished and coated specimens. Results of the MTT assay revealed that the TiN and TiAlN film coated groups were significantly higher in cell proliferation and viability than the polished and control groups (p<0.05).
  
  
  CONCLUSIONS
  The biocompatibility of Ni-based alloy was increased significantly after nitride film coating.
authors.affiliation: Institute of Oral Biology, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Chia-Chi
authors.initials: CC
authors.lastname: Chien
authors.forename: Kuan-Ting
authors.initials: KT
authors.lastname: Liu
authors.forename: Jenq-Gong
authors.initials: JG
authors.lastname: Duh
authors.forename: Kuo-Wei
authors.initials: KW
authors.lastname: Chang
authors.forename: Kwok-Hung
authors.initials: KH
authors.lastname: Chung
mesh_terms: D000497:Alloys / Q000633:toxicity*; D002448:Cell Adhesion / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D048430:Cell Shape / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D002858:Chromium Alloys / Q000633:toxicity*; D020099:Coated Materials, Biocompatible / Q000633:toxicity*; D004396:Coloring Agents; D003599:Cytoskeleton / Q000187:drug effects; D003722:Dental Alloys / Q000633:toxicity*; D003775:Dental Polishing; D005347:Fibroblasts / Q000187:drug effects*; D005881:Gingiva / Q000187:drug effects*; D006801:Humans; D008422:Materials Testing; D008856:Microscopy, Fluorescence; D013499:Surface Properties; D013500:Surface Tension; D013778:Tetrazolium Salts; D013844:Thiazoles; D013997:Time Factors; D014025:Titanium / Q000633:toxicity*; D017155:Wettability
chemical_list: D000497:Alloys; D002858:Chromium Alloys; D020099:Coated Materials, Biocompatible; D004396:Coloring Agents; D003722:Dental Alloys; D013778:Tetrazolium Salts; D013844:Thiazoles; C528635:titanium aluminum alloy; C039459:ticonium; C041500:titanium nitride; D014025:Titanium; C022616:thiazolyl blue