Date of Graduation
School of Dentistry
Anthony T Borgia
Introduction.;Excessive dentin removal in a single direction within the canal causes canal transportation. A study by Peters OA has shown that the canal transportation is highest apically. A number of cleaning and shaping principles have been previously suggested and should be followed to achieve optimum results. These principles include the developing of a continuously tapering funnel from the coronal access cavity to the root apex, following the original canal shape and maintaining the apical foramen in its original spatial relationship both to the periapical tissues and to the root surface. The aim of this study is to construct detailed three-dimensional images of root systems and measure the changes in canal anatomy, using TRUShape RTM 3D Conforming Files, and EdgeEvolve(TM) files.;Materials and Methods.;Thirty maxillary molars were mounted at the cemento-enamel junction in modified poly-propylene 50 ml centrifuge tubes using a radiolucent methyl methacrylate acrylic resin. All specimens were preoperatively scanned with microCT-40. Images from the microCT-40 were transferred to ImageJRTM image analyzing software to assess the initial dentin thickness measured 1 mm from the apex. Canals were then instrumented to length with both file systems. Each specimen was measured after canal preparation in a manner identical to the pre-instrumentation measurement. Wilcoxon Rank Sum test was used to determine statistical variance between procedures. Both instruments resulted in no procedural errors.;Results Transportation scores were 95+/-60 mum for TRUShape and 120+/-70 mum for EdgeEvolve. The overall canal transportation results by TRUShape were significantly lower (p<.05). However, both file systems had similar centric ratios with no statistically significant difference.;ConclusionThe amount of remaining dentin after shaping depends on canal transportation, and, in return, this number depends on canal curvature. Therefore, it is difficult to compare the present results with data from other studies; however, between the two instruments tested under present conditions, TRUShapeRTM, resulted in less canal transportation and more remaining dentin in the canal walls. It continues to be a matter of debate if the amount of preserved structure will translate into enhanced clinical outcomes.
Sakr, Wisam, "Apical Canal Transportation after Instrumentation with Two New Rotary Files; A comparative Study with Micro CT" (2016). Graduate Theses, Dissertations, and Problem Reports. 6557.