title: [Effect of cold-light bleaching technique on human permanent teeth enamel surface].
abstract: OBJECTIVE
  To study the effects of the cold-light bleaching technique on crystals and microstructure of the dental enamel.
  
  
  METHODS
  The human premolars extracted for orthodontic reasons were treated by a standard cold-light bleaching procedure. After the treatment, all samples were detected by high resolution micro-area X-ray diffractometer, Fourier transform infrared spectroscope and scanning electron microscope.
  
  
  RESULTS
  After the permanent teeth were treated with cold-light bleaching technique, the enamels' crystal dimension, crystallinity decreased and irregular surfaces and shallow disk pits appeared.
  
  
  CONCLUSIONS
  The cold-light bleaching technique could lead to the changes of crystals and microstructure in the surface layer of dental enamel.
authors.affiliation: State Key Laboratory of Oral Diseases, Sichuan Sichuan University, Chengdu 610041, China.
authors.forename: Jian-wen
authors.initials: JW
authors.lastname: Huang
authors.forename: Xin-chang
authors.initials: XC
authors.lastname: Shi
authors.forename: Jing-lin
authors.initials: JL
authors.lastname: Zhou
authors.forename: Wei
authors.initials: W
authors.lastname: Li
mesh_terms: D001641:Bicuspid; D003743:Dental Enamel / Q000528:radiation effects* / Q000648:ultrastructure; D006801:Humans; D008027:Light; D008855:Microscopy, Electron, Scanning; D017550:Spectroscopy, Fourier Transform Infrared; D014073:Tooth Bleaching / Q000379:methods*