title: Assessment of antibacterial and cytotoxic effects of orthodontic stainless steel brackets coated with different phases of titanium oxide: An in-vitro study.
abstract: BACKGROUND
  Our objective was to assess the antibacterial and cytotoxic effects of orthodontic stainless steel brackets coated with different phases of photocatalytic titanium oxide.
  
  
  METHODS
  From a total sample of 115 brackets, 68 orthodontic stainless steel brackets were coated with titanium oxide using a radiofrequency magnetron sputtering machine. The coated brackets were then converted into 34 each of the anatase and rutile phases of titanium oxide. These brackets were subdivided into 4 groups for antibacterial study and 3 groups for cytotoxicity study. Brackets for the antibacterial study were assessed against the Streptococcus mutans species using microbiologic tests. Three groups for the cytotoxicity study were assessed using the thiazolyl tetrazolium bromide assay.
  
  
  RESULTS
  The antibacterial study showed that both phases were effective, but the rutile phase of photocatalytic titanium oxide had a greater bactericidal effect than did the anatase phase. The cytotoxicity study showed that the rutile phase had a greater decrease in viability of cells compared with the anatase phase.
  
  
  CONCLUSIONS
  It is recommended that orthodontic brackets be coated with the anatase phase of titanium oxide since they exhibited a significant antibacterial property and were only slightly cytotoxic.
authors.affiliation: Department of Orthodontics and Dentofacial Orthopaedics, Faculty of Dental Sciences, Sri Ramachandra University, Chennai, Tamil Nadu, India. Electronic address: rdroshendaniel94@gmail.com.
authors.forename: Roshen Daniel
authors.initials: RD
authors.lastname: Baby
authors.affiliation: Department of Orthodontics and Dentofacial Orthopaedics, Faculty of Dental Sciences, Sri Ramachandra University, Chennai, Tamil Nadu, India.
authors.forename: Siva
authors.initials: S
authors.lastname: Subramaniam
authors.affiliation: Department of Microbiology, Sri Ramachandra Medical College and Research Institute, Sri Ramachandra University, Chennai, Tamil Nadu, India.
authors.forename: Ilakkiya
authors.initials: I
authors.lastname: Arumugam
authors.affiliation: Department of Orthodontics and Dentofacial Orthopaedics, Faculty of Dental Sciences, Sri Ramachandra University, Chennai, Tamil Nadu, India.
authors.forename: Sridevi
authors.initials: S
authors.lastname: Padmanabhan
mesh_terms: D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D003603:Cytotoxins / Q000627:therapeutic use*; D066298:In Vitro Techniques; D016910:Orthodontic Brackets / Q000382:microbiology*; D013295:Streptococcus mutans / Q000254:growth & development; D014025:Titanium / Q000627:therapeutic use*
chemical_list: D000900:Anti-Bacterial Agents; D003603:Cytotoxins; C009495:titanium dioxide; D014025:Titanium