title: [Study of the correlation between Streptococcus mutans' adhesion and surface corrosion in casting titanium and Ti alloy].
abstract: OBJECTIVE
  To investigate the correlation between Streptococcus mutans' adhesion and surface corrosion of the casting titanium and Ti alloy with different kinds of polishing.
  
  
  METHODS
  The casting titanium and Ti alloy were respectively processed into size of 30 mm x 8mm x 1mm in tablets. Each material was prepared for 32 specimens, randomly divided into two groups, dealt with mechanical polishing and electrochemistry polishing, and then randomly divided into four groups (blank control, media control, inoculated media control for three months and six months).Four specimens were used in each group under hypoxia conditions. The labeled specimen surfaces were then aseptically placed in the test tube with one transfer per week. The specimens were removed and sterilized. The surface roughness of specimens was measured by FTS i120 contourgraph and the alteration of the surface was observed under SIRION scanning electron microscope. One-way ANOVA was performed with SPSS11.O software package.
  
  
  RESULTS
  In casting titanium, blank control media control, inoculated media control for three months and six months showed no influence on Ra value(P>0.05).In Ti alloy, the Ra value of the inoculated media control group was significantly different from those of blank control group(P<0.05) and metal control group(P<0.05). All the specimen surfaces had pits in disorder and in different size.
  
  
  CONCLUSIONS
  Streptococcus mutans' adhesion causes surface corrosion of the casting titanium and Ti alloy, and mechanical polishing and electrochemistry polishing have no influence on corrosion.
authors.affiliation: Department of Prosthodontics, Zhejiang University, Hangzhou 310006, Zhejiang Province, China. dbsxt@163.com
authors.forename: Xiao-ting
authors.initials: XT
authors.lastname: Shen
authors.forename: Li
authors.initials: L
authors.lastname: Liu
authors.forename: Kang-nan
authors.initials: KN
authors.lastname: Mo
authors.forename: Yan-zhen
authors.initials: YZ
authors.lastname: Zhang
authors.forename: Bo-gui
authors.initials: BG
authors.lastname: Liang
mesh_terms: D000497:Alloys; D003343:Corrosion; D003722:Dental Alloys; D008422:Materials Testing; D013295:Streptococcus mutans / Q000502:physiology*; D013499:Surface Properties; D014025:Titanium
chemical_list: D000497:Alloys; D003722:Dental Alloys; D014025:Titanium