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Distortion and breakage of Liberator, EndoSequence, and ProFile systems in severely curved roots of molars
Jeffrey T Stewart1, Shawn Lafkowitz, Keith Appelbaum
1Department of Endodontics, UMDNJ-NJDS, Newark, NJ 07103, USA. jeffrey.stewart@umdnj.edu
Introduction:
The aim of this study was to investigate the incidence of endodontic file distortion and breakage when the Liberator (Miltex Inc, York, PA), EndoSequence (Brasseler USA, Savannah, GA), and ProFile (Tulsa Dental Products, Tulsa, OK) systems were used to instrument severely curved root canals of extracted human molars.
Methods:
Eighty-four roots of extracted human molars with curvatures measuring 40 degrees to 80 degrees were used. The roots were randomly assigned into four groups based on the rotary instrumentation system: group 1, ProFile (.04 taper); group 2, EndoSequence (.04 taper); group 3, Liberator (.04 taper); and group 4, Liberator (.02 taper).
Results:
File distortion was 19.4%, 10%, 44.4%, and 59.1% for the ProFile, EndoSequence, and Liberator .04 and Liberator .02 groups, respectively. There were statistically significant differences between the ProFile and Liberator .04 groups (p < 0.05), the ProFile and Liberator .02 groups (p < 0.01), the EndoSequence and Liberator .04 groups (p < 0.01), and the EndoSequence and Liberator .02 groups (p < 0.01). Broken files occurred in 2.8% of the ProFile group and 7.4% of the Liberator .04 group. There were no broken files in the EndoSequence or Liberator .02 groups. No statistically significant differences were found among the four groups (p = 0.28) with regard to file breakage.
Conclusion:
It can be concluded that more file distortions occurred in both Liberator groups than with either the ProFile or the EndoSequence groups to a statistically significant degree.
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