evidence: The results showed that residual antimicrobial activity of CHX was significantly higher in gutta-percha/AH26 samples than in Resilon/RealSeal SE samples (P=0.02 at one week and P=0.003 at three and six weeks, respectively).
intervention: gutta-percha/AH26 
comparator: Resilon/RealSeal SE samples
outcome: residual antimicrobial activity of CHX at one week and at three and six weeks