title: The effect of blood contamination on the compressive strength of calcium-enriched mixture.
abstract: BACKGROUND
  In clinical situations, Calcium-Enriched Mixture (CEM) comes into direct contact or even mixes with blood during or after placement.
  
  
  OBJECTIVE
  The aim of this study was to evaluate the effect of blood contamination on the compressive strength of CEM.
  
  
  METHODS
  Three experimental groups were included in this study. In the first group, CEM was mixed with distilled water and was exposed to normal saline (control group). In the second group, CEM cement was mixed with distilled water and then was exposed to blood. In the third group, CEM was mixed with and exposed to blood. Nine custom-made two-part split Plexiglas molds with five holes were used to form CEM samples for compressive strength testing (15 samples in each group). After 7 days of incubation, compressive bond strength testing was performed using a universal testing machine. Data were statistically analyzed using the Mann-Whitney U test with a significance level of p< 0.05.
  
  
  RESULTS
  Nine samples from group 3 were fractured during removal from the molds; the other six blocks had some cracks on their surfaces. Therefore, a compressive strength measurement was not obtainable for this group. No statistically significant difference was found between groups 1 and 2 (p> 0.05).
  
  
  CONCLUSIONS
  It can be concluded that exposure to blood does not adversely affect the compressive strength of CEM, but incorporation of blood makes the cement very brittle.
authors.affiliation: Dept. of Endodontics, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Alireza
authors.initials: A
authors.lastname: Adl
authors.affiliation: Dept. of Endodontics, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Nooshin Sadat
authors.initials: NS
authors.lastname: Shojaee
authors.affiliation: Dept. of Endodontics, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Fereshte
authors.initials: F
authors.lastname: Sobhnamayan
authors.affiliation: Student, Biomaterial Research Centre, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: Mohammadsaeed
authors.initials: M
authors.lastname: Hashemzade
keywords: Blood contamination; CEM; Calcium-enriched mixture; Compressive strength