title: Cytotoxicity of two available mineral trioxide aggregate cements and a new formulation on human gingival fibroblasts.
abstract: OBJECTIVE
  The purpose of this study was to investigate the cytotoxicity of nanohybrid mineral trioxide aggregate (MTA) in comparison with calcium-enriched mixture (CEM) cement and MTA-Angelus, using human gingival fibroblasts (HGFs).
  
  
  METHODS
  Nine disc-shaped specimens of each material (in 2 set stat: A, set for 24 h; B, set for 30 min; and C, fresh stat) were prepared. HGFs were exposed to tested materials' extracts or control media. Cytotoxicity testing was performed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide assay in two time intervals.
  
  
  METHODS
  Results were evaluated by one-way ANOVA andt-test. Statistical significance was set atP< 0.05.
  
  
  RESULTS
  CEM cement demonstrated favorable cell viability values when completely set (24 h set MTA = 24 h set CEM) at both time intervals. Interestingly, 24 h after incubation, CEM in Groups B and C demonstrated higher cell viability values than MTA (P< 0.05). However, after 72 h of incubation, these groups of CEM and MTA showed equal cell viability. All samples of nanohybrid MTA had slight cytotoxic effects after 24 h of incubation, and moderate cytotoxic effects after 72 h of incubation.
  
  
  CONCLUSIONS
  Set CEM and set MTA-Angelus exerted similar, favorable effects on cell viability. However, within the limitations of thisin vitrostudy, the results suggest that nanohybrid MTA could not be recommended as a material of choice for cervical root resorption.
authors.affiliation: Department of Dental Biomaterials, School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Department of Tissue Engineering, School of Advanced Technologies in Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Maryam
authors.initials: M
authors.lastname: Torshabi
authors.affiliation: Department of Periodontics, School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Reza
authors.initials: R
authors.lastname: Amid
authors.affiliation: Department of Periodontics, School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Mahdi
authors.initials: M
authors.lastname: Kadkhodazadeh
authors.affiliation: Department of Periodontics, School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Sara Eslami
authors.initials: SE
authors.lastname: Shahrbabaki
authors.affiliation: Department of Dental Biomaterials, School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Department of Tissue Engineering, School of Advanced Technologies in Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Fahimeh S
authors.initials: FS
authors.lastname: Tabatabaei
keywords: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide assay; Angelus mineral trioxide aggregate; calcium-enriched mixture; calcium-enriched mixture cement; cytotoxicity; mineral trioxide aggregate