title: The effect of the surface characteristics of various substrates on fluorapatite crystal growth, alignment, and spatial orientation.
abstract: BACKGROUND
  Fluorapatite-coated materials have potential application for dental and medical implants. In tooth development, the prism-like structure in enamel is thought to be created by the cells and proteins involved in enamel formation and maturation. This study investigated whether the substrate itself on which the films are grown, without the inclusion of cells or proteins, may affect their crystal alignment and three-dimensional morphology.
  
  
  METHODS
  Human dentin/enamel junction (DEJ), dentin, stainless steel plates, etched stainless steel plates, etched titanium plates, glass, and mica were used as substrates to grow fluorapatite (FA) crystals using a hydrothermal method. FA crystal growth on these substrates was observed using scanning electron microscopy.
  
  
  RESULTS
  Under hydrothermal conditions, enamel prism-like structure could not be seen when the crystals were grown on mica or glass. Organized bundles of FA were created using DEJ, but not dentin, although it supported crystal growth. Etched stainless steel and titanium supported the growth of aligned FA crystals, but without the prism structure.
  
  
  CONCLUSIONS
  The surface properties of the substrate on which the nanocrystals grow appear to affect their alignment, organization, and consequently the formation of a prism structure.
authors.affiliation: Department of Cariology, Restorative Sciences, and Endodontics, University of Michigan School of Dentistry, Ann Arbor, MI, USA. czajak@it.pl
authors.forename: Agata Ewa
authors.initials: AE
authors.lastname: Czajka-Jakubowska
authors.forename: Jun
authors.initials: J
authors.lastname: Liu
authors.forename: Sywe-Ren
authors.initials: SR
authors.lastname: Chang
authors.forename: Brian Henry
authors.initials: BH
authors.lastname: Clarkson
mesh_terms: D000134:Acid Etching, Dental; D000538:Aluminum Silicates / Q000737:chemistry; D001031:Apatites / Q000737:chemistry*; D003460:Crystallization; D003743:Dental Enamel / Q000737:chemistry; D003804:Dentin / Q000737:chemistry; D005898:Glass / Q000737:chemistry; D006801:Humans; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D008963:Molar; D043942:Nanotubes / Q000648:ultrastructure; D013193:Stainless Steel / Q000737:chemistry; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry
chemical_list: D000538:Aluminum Silicates; D001031:Apatites; D013193:Stainless Steel; D014025:Titanium; C025105:fluorapatite; C011934:mica