title: In Vitro Evaluation of Different Solvents for Retrieval of Mineral Trioxide Aggregate and Calcium-Enriched Mixture.
abstract: BACKGROUND
  The purpose of this study was to evaluate the effect of different solvents; carbonic acid (H2CO3), hydrochloric acid (HCl), chlorhexidine (CHX) and sodium hypochlorite (NaOCl) on the surface hardness of mineral trioxide aggregate (MTA) and calcium-enriched mixture (CEM) cement.
  
  
  METHODS
  Plexiglass molds were prepared and filled with Angelus MTA or CEM cement and then exposed to 2% carbonic acid, 37% hydrochloric acid, 2% chlorhexidine, 5.25% sodium hypochlorite and normal saline at intervals of 1 and 21 days, respectively (n=4). Surface microhardness of all specimens was analyzed by a universal testing machine and an electron microscope for some selected samples. Data were analyzed using the three-way ANOVA. Subgroup analysis was performed by Student's t-test, One-way ANOVA and Tukey's tests. The level of significance was set at 0.05.
  
  
  RESULTS
  On the first day, all solvents and on 21(st) day HCl, and H2CO3 were more effective in reducing the microhardness of MTA compared to CEM cement (P<0.05).
  
  
  CONCLUSIONS
  The two experimental cements were differently affected by the solvents at specific time intervals. The solvents were more effective on MTA.
authors.affiliation: Department of Endodontics, Dental School, Shiraz University of Medical Sciences, Shiraz, Iran;
authors.forename: Nooshin Sadat
authors.initials: NS
authors.lastname: Shojaee
authors.affiliation: Department of Endodontics, Biomaterials Research Center, Dental School, Shiraz University of Medical Sciences, Shiraz, Iran;
authors.forename: Alireza
authors.initials: A
authors.lastname: Adl
authors.affiliation: Department of Endodontics, Dental School, Shiraz University of Medical Sciences, Shiraz, Iran;
authors.forename: Fereshte
authors.initials: F
authors.lastname: Sobhnamayan
authors.affiliation: Student, Dental School, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Azam
authors.initials: A
authors.lastname: Khademi
authors.affiliation: Student, Dental School, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Mina
authors.initials: M
authors.lastname: Hamedi
keywords: Calcium-Enriched Mixture; Microhardness; Mineral Trioxide Aggregate; Retrieval