title: Effect of different mixing methods on the bacterial microleakage of calcium-enriched mixture cement.
abstract: BACKGROUND
  Calcium-Enriched Mixture Cement is used in the field of endodontics. It is similar to Mineral Trioxide Aggregate in its main ingredients.The present study investigated the effect of different mixing methods on the bacterial microleakage of CEM cement.
  
  
  METHODS
  A total of 55 human single-rooted human permanent teeth were decoronated so that 14- mm-long samples were obtained and obturated with AH26 sealer and gutta-percha using lateral condensation technique. Three millimeters of the root end were cut off and randomly divided into 3 groups of 15 each (3 mixing methods of amalgamator, ultrasonic and conventional) and 2 negative and positive control groups (each containing 5 samples). BHI (Brain-Heart Infusion Agar) suspension containing Enterococcus faecalis was used for bacterial leakage assessment. Statistical analysis was carried out using descriptive statistics, Kaplan‒Meier survival analysis with censored data and log rank test. Statistical significance was set at P<0.05.
  
  
  RESULTS
  The survival means for conventional, amalgamator and ultrasonic methods were 62.13±12.44, 68.87±12.79 and 77.53±12.52 days, respectively. The log rank test showed no significant differences between the groups.
  
  
  CONCLUSIONS
  Based on the results of the present study it can be concluded that different mixing methods had no significant effect on the bacterial microleakage of CEM cement.
authors.affiliation: Dental and periodontal research center, Dentistry Faculty, Tabriz University of medical sciences, Tabriz, Iran - dr.jafarif@gmail.com.
authors.forename: Shahriar
authors.initials: S
authors.lastname: Shahi
authors.forename: Soniya
authors.initials: S
authors.lastname: Jeddi Khajeh
authors.forename: Saeed
authors.initials: S
authors.lastname: Rahimi
authors.forename: Hamid R
authors.initials: HR
authors.lastname: Yavari
authors.forename: Farnaz
authors.initials: F
authors.lastname: Jafari
authors.forename: Mohammad
authors.initials: M
authors.lastname: Samiei
authors.forename: Negin
authors.initials: N
authors.lastname: Ghasemi
authors.forename: Amin
authors.initials: A
authors.lastname: Salem Milani