Smear layer removal with passive ultrasonic irrigation and the NaviTip FX: a scanning electron microscopic study.
OBJECTIVE
The aim of this study was to compare the effect of continuous, intermittent passive ultrasonic irrigation (PUI) and active scrubbing of irrigants with NaviTip FX (Ultradent, South Jordan, UT) in removing smear layer.


METHODS
Forty single-rooted teeth were randomly divided into 5 test groups and subjected to final irrigation with 17% EDTA followed by 2.5% NaOCl for 1 minute each using different activation methods: no activation (control), brushing with NaviTip FX, continuous PUI with irrigant delivered at pulp chamber, continuous PUI with irrigant delivered through the ultrasonic unit, and intermittent PUI. Specimens were examined under scanning electron microscope, and the data were analyzed using Friedman 2-way analysis of variance, Kruskal-Wallis, and Mann-Whitney U tests.


RESULTS
NaviTip FX and intermittent PUI showed significantly lower smear score than other groups at the 3 mm level (P < .05).


CONCLUSIONS
Both brush and intermittent ultrasonic activation were effective in the removal of smear layer from the apical third.
Goel
Shweta
S
Department of Conservative Dentistry and Endodontics, Postgraduate Institute of Medical Sciences, Rohtak, Haryana, India.
Tewari
Sanjay
S
D003786:Dental Pulp Cavity / Q000648:ultrastructure*; D003804:Dentin / Q000648:ultrastructure*; D004492:Edetic Acid / Q000627:therapeutic use; D004867:Equipment Design; D006801:Humans; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D009339:Needles; D012388:Root Canal Irrigants / Q000627:therapeutic use*; D018915:Root Canal Preparation / Q000295:instrumentation / Q000379:methods*; D016369:Smear Layer; D012973:Sodium Hypochlorite / Q000627:therapeutic use; D013594:Syringes; D007507:Therapeutic Irrigation; D019227:Tooth Apex / Q000648:ultrastructure; D014464:Ultrasonic Therapy / Q000295:instrumentation / Q000379:methods*
D012388:Root Canal Irrigants; D004492:Edetic Acid; D012973:Sodium Hypochlorite