Comparison of the effect of two endodontic irrigation protocols on the elimination of bacteria from root canal system: a prospective, randomized clinical trial.
BACKGROUND
The purpose of this prospective, randomized clinical study was to compare the results of a nonactivated single-irrigation protocol (NAI) that used only 1% NaOCl with a passive ultrasonic multi-irrigation protocol (PUI) that used 1% NaOCl, 17% ethylenediaminetetraacetic acid, and 2% chlorhexidine in rendering canals bacteria free. In addition, the effect of a second-visit instrumentation after intra-appointment calcium hydroxide (CaOH(2)) was also evaluated in bacterial elimination.


METHODS
Fifty patients were recruited with a posterior tooth requiring primary endodontic treatment of apical periodontitis. Standard nonsurgical endodontic therapy was performed on both groups in a 2-visit approach by using calcium hydroxide intracanal medicament. Teeth were randomly treated with the NAI or PUI protocols in the first visit after complete instrumentation. Bacterial cultures were obtained at 4 periods during treatment from the canals: (1) before instrumentation, (2) after irrigation protocol, (3) after CaOH(2) medication, and (4) before obturation. Statistical analysis was performed on data by using the Fisher exact test and multivariate analysis.


RESULTS
NAI and PUI rendered canals 80% and 84% bacteria free, respectively, at the end of the first visit. After CaOH(2) medication the total sample (NAI + PUI) had increased to 87% bacteria free, and the second-visit instrumentation resulted in a total of 91% bacteria free. These differences were not significant (P > .05).


CONCLUSIONS
There was no statistical difference between irrigation methods. Each protocol resulted in a high frequency of negative cultures. This high frequency of negative cultures obtained in 1 visit is most likely related to an increased volume and depth of irrigation compared with previously reported protocols.
Division of Endodontology, School of Dental Medicine, University of Connecticut, Farmington, CT 06030, USA.
Christopher
C
Beus
Kamran
K
Safavi
Jeffrey
J
Stratton
Blythe
B
Kaufman
D000704:Analysis of Variance; D016009:Chi-Square Distribution; D002710:Chlorhexidine / Q000627:therapeutic use; D015169:Colony Count, Microbial; D003786:Dental Pulp Cavity / Q000382:microbiology*; D004492:Edetic Acid / Q000627:therapeutic use; D005260:Female; D006801:Humans; D016014:Linear Models; D008297:Male; D010485:Periapical Periodontitis / Q000382:microbiology / Q000628:therapy*; D011446:Prospective Studies; D012388:Root Canal Irrigants / Q000627:therapeutic use*; D018915:Root Canal Preparation / Q000379:methods*; D012973:Sodium Hypochlorite / Q000627:therapeutic use; D007507:Therapeutic Irrigation / Q000379:methods*; D014464:Ultrasonic Therapy
D012388:Root Canal Irrigants; D004492:Edetic Acid; D012973:Sodium Hypochlorite; D002710:Chlorhexidine