Calcium hydroxide has limited effectiveness in eliminating bacteria from human root canal when assessed by culture techniques
AIM To determine to what extent does calcium hydroxide intracanal medication eliminate bacteria from human root canals , compared with the same canals before medication , as measured by the number of positive cultures , in patients undergoing root canal treatment for apical periodontitis ( teeth with an infected root canal system ) .
Bacterial reduction with nickel-titanium rotary instrumentation.
The purpose of this study was to compare intracanal bacterial reduction on teeth instrumented with 0.04 tapered nickel-titanium ( NiTi ) rotary instrumentation to bacterial reduction when using a stainless-steel K-file step-back technique using sterile saline irrigation .  Forty-eight patients with apical periodontitis were r and omly assigned treatment type . The canals were sample d before , during , and after instrumentation . The sample s were incubated anaerobically for 7 days at 37 degrees C , colony-forming unit numbers calculated , and a log transformation performed to normalize the counts . Teeth exhibiting apical periodontitis were uniformly infected , whereas vital control teeth were not . A similar and uniform reduction occurred with progressive filing , regardless of technique ( p < 0.0001 ) . There was no detectable difference in colony-forming unit count after NiTi rotary or stainless-steel h and instrumentation ( p = 0.42 ) . Neither technique could predictably render canals free of bacteria . The results of this study indicate NiTi rotary and stainless-steel h and K-file step-back instrumentation techniques were not significantly different in their ability to reduce intracanal bacteria
Calcium hydroxide has limited effectiveness in eliminating bacteria from human root canal when assessed by culture techniques
AIM To determine to what extent does calcium hydroxide intracanal medication eliminate bacteria from human root canals , compared with the same canals before medication , as measured by the number of positive cultures , in patients undergoing root canal treatment for apical periodontitis ( teeth with an infected root canal system ) .