%0 Journal Article
%T Effect of Patency File on Transportation and Curve Straightening in Canal Preparation with ProTaper System
%A Seyed Mohsen Hasheminia
%A Nastaran Farhadi
%A Ali Shokraneh
%J ISRN Dentistry
%D 2013
%R 10.1155/2013/704027
%X The aim of this ex vivo study was to evaluate the effect of using a patency file on apical transportation and curve straightening during canal instrumentation with the ProTaper rotary system. Seventy permanent mandibular first molars with mesiobuccal canals, measuring 18¨C23£¿mm in length and with a 25¨C40¡ã curvature (according to the Schneider method), were selected. The working lengths were determined and the teeth were mounted and divided into two experimental groups: (A) prepared by the ProTaper system without using a patency file ( ) and (B) prepared by the ProTaper system using a patency file ( ). Radiographs taken before and after the preparation were imported into Photoshop software and the apical transportation, and curve straightening were measured. Data were analyzed using independent t-test. Partial correlation analysis was performed to evaluate the relationship between the initial curvature, transportation, and curve straightening ( ). Using a patency file during canal preparation significantly decreased both apical transportation and curve straightening ( ). There were significant relationships between the angle of curvature, transportation and curve straightening in pairs ( ). Apical patency is recommended during root canal preparation with the ProTaper rotary system. 1. Introduction Cleaning and shaping the root canal system is an important step in the success of root canal therapy [1]. Three-dimensional maintenance of the original shape of the root canal is necessary during canal preparation. To achieve this goal, cleaning and shaping should be performed circumferentially, foramen transportation should not occur, and apical foramen should be maintained in its original position [1]. During the root canal instrumentation pulpal and dentinal debris can block the apical third of the root canal, which can increase the chance of ledge formation, transportation, and perforation [2]. These procedural errors can be prevented with the use of a patency file during instrumentation. NiTi rotary instruments obviously decrease several clinical complications, such as canal blockage, ledge formation, transportation, and perforation; they also reduce operator fatigue and the time required for canal preparation [3¨C6]. ProTaper is one of the NiTi rotary systems, with progressive tapering and a convex triangular cross-sectional cutting blade designed for increased flexibility and cutting efficiency. This system has great applicability in curved canals. Several studies have evaluated canal transportation and curve straightening of ProTaper files. In one study,
%U http://www.hindawi.com/journals/isrn.dentistry/2013/704027/