title: Cytotoxic effects of orthodontic composites.
abstract: OBJECTIVE
  To evaluate the cytotoxic effects of five different light-cured orthodontic bonding composites.
  
  
  METHODS
  The orthodontic composites Heliosit Orthodontic (Ivoclar), Transbond XT (3M Unitek), Bisco ORTHO (Bisco), Light Bond (Reliance), and Quick Cure (Reliance) were prepared, and the samples were extracted in 3 mL of BME (Basal Medium Eagle) with 10% newborn calf serum for 24 hours. The L929 cells were plated (25,000 cells/mL) in a 96-well dish and maintained in a humidified incubator for 24 hours at 37 degrees C, 5% CO(2), and 95% air. After 24 hours of incubation of the cells, the incubation medium was replaced by the immersed medium in which the samples were stored. Then, L929 cells were incubated in contact with eluates for 24 hours. The cell mitochondrial activity was evaluated by the methyl tetrazolium (MTT) test. Twelve wells were used for each specimen, and the MTT tests were applied two times. The data were statistically analyzed by one-way analysis of variance (ANOVA) and Tukey HSD tests.
  
  
  RESULTS
  Results with L929 fibroblasts demonstrated that except for Transbond XT, freshly prepared composite materials did not reduce vital cell numbers (P > .05) compared with the control group. Our data demonstrate that Transbond XT showed significant cytotoxicity compared with the control group.
  
  
  CONCLUSIONS
  Results indicate that tested orthodontic bonding composites are suitable for clinical application, but that further studies using different test methods are needed for Transbond XT.
authors.affiliation: Department of Orthodontics, Inönü University, Malatya, Turkey. siddikmalkoc@yahoo.com
authors.forename: Siddik
authors.initials: S
authors.lastname: Malkoc
authors.forename: Bayram
authors.initials: B
authors.lastname: Corekci
authors.forename: Hayriye Esra
authors.initials: HE
authors.lastname: Ulker
authors.forename: Muhammet
authors.initials: M
authors.lastname: Yalçin
authors.forename: Abdülkadir
authors.initials: A
authors.lastname: Sengün
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D048430:Cell Shape / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D007739:L Cells / Q000187:drug effects; D055115:Light-Curing of Dental Adhesives; D051379:Mice; D008928:Mitochondria / Q000187:drug effects; D016910:Orthodontic Brackets; D019279:Resin Cements / Q000633:toxicity*; D018709:Statistics, Nonparametric
chemical_list: D019279:Resin Cements; C477790:Transbond XT