Comparative Evaluation of Smear Layer and Debris on the Canal Walls prepared with a Combination of Hand and Rotary ProTaper Technique using Scanning Electron Microscope.
BACKGROUND
The effect of smear layer and debris on the success rate of endodontic treatment has not yet been definitely determined. So the present study was aimed to evaluate the amount of smear layer and debris on the canal walls prepared with a combination of hand and rotary ProTaper technique using NaOCl and ethylenediaminetetraacetic acid (EDTA) alternately as root canal irrigants using scanning electron microscope (SEM).


METHODS
Eighty intact freshly extracted human permanent mandibular premolar teeth were collected and randomly divided equally into four groups. In group I canals were prepared with hand K-Flexofiles; group II with rotary ProTaper instruments; group III with rotary ProTaper instruments and final instrumentation was done with hand K-Flexofile; group IV with rotary ProTaper instruments and final instrumentation was done with RC-Prep and irrigated with 1 mL of normal saline. In all groups canals were irrigated using NaOCl and EDTA alternately. After instrumentation, the teeth were prepared for SEM examination using five-score indices for debris and smear layer at coronal, middle, and apical third levels. Statistical analysis was performed using chi-square test (p < 0.05) and Kruskal-Wallis test (p < 0.05).


RESULTS
Statistically significant difference was observed between the groups in cleaning the apical third. Groups I and III showed better canal cleanliness compared to group II. The use of EDTA and NaOCl in group III was more effective in removing debris and smear layer compared to EDTA and normal saline in group IV. Regardless of the instrumentation technique employed and the irrigant used, the cleaning ability decreased in the apical third, resulting in higher debris and smear layer scores compared to coronal and middle third levels.


CONCLUSIONS
None of the instrumentation techniques in the present study could completely eliminate the smear layer and debris from the canal walls. Instrumentation of the canals with hand files after automated rotary preparation could result in cleaner canal walls.


CONCLUSIONS
Alternate irrigation with NaOCl and EDTA is effective in the removal of debris and smear layer in the coronal and middle level, but the effectiveness in the apical third is less.
Reader, Department of Conservative Dentistry and Endodontics Triveni Institute of Dental Sciences, Hospital & Research Centre, Bilaspur, Chhattisgarh, India, Phone: +9663904586, e-mail: drkirans@yahoo.co.in.
S
S
Kiran
Department of Dentistry, Chhattisgarh Institute of Medical Sciences, Bilaspur, Chhattisgarh, India.
Sandeep
S
Prakash
Department of Endodontics, Private Practice, Bilaspur Chhattisgarh, India.
Pujari R
PR
Siddharth
Department of Conservative Dentistry and Endodontics Triveni Institute of Dental Sciences, Hospital & Research Centre, Bilaspur, Chhattisgarh, India.
Supradip
S
Saha
Department of Conservative Dentistry and Endodontics Triveni Institute of Dental Sciences, Hospital & Research Centre, Bilaspur, Chhattisgarh, India.
Naiza E
NE
Geojan
Department of Conservative Dentistry and Endodontics Triveni Institute of Dental Sciences, Hospital & Research Centre, Bilaspur, Chhattisgarh, India.
Mookambika
M
Ramachandran
D001641:Bicuspid / Q000601:surgery* / Q000648:ultrastructure; D003762:Dental Instruments; D004492:Edetic Acid / Q000494:pharmacology; D006801:Humans; D066298:In Vitro Techniques; D008855:Microscopy, Electron, Scanning; D011897:Random Allocation; D012388:Root Canal Irrigants / Q000494:pharmacology; D018915:Root Canal Preparation / Q000295:instrumentation / Q000379:methods*; D016369:Smear Layer; D012973:Sodium Hypochlorite / Q000494:pharmacology
D012388:Root Canal Irrigants; D004492:Edetic Acid; D012973:Sodium Hypochlorite
Debris; Nickel-Titanium instruments; Rotary ProTaper; Scanning electron microscope; Smear layer.