مقايسه ميزان دبري و لايه اسمير باقيمانده در ديواره كانال ريشه پس از آماده سازي به در روش دستي و چرخشي در كانال هاي خميده

Comparison of debris and smear layer remaining in root canal wall after preparation with rotary and hand instruments in curved canals

Background & Aim: The purpose of this scanning electron microscope (SEM) study was to compare the cleanliness of the root canal walls following either a manual or a rotary technique of canal instrumentation. The hypothesis was that a rotary technique would produce a cleaner root canal. Methods & Materials: Manual filing was performed on 24 extracted teeth with the curvature more than 20° using stainless steel K-flexofile (DENTSPLY MAILLEFER). Powered instrumentation was carried out on a further 24 extracted teeth, using Hero 642 (Micro Mega France) nickel-titanium files in a handpiece NSK (ENDO-MAT TC) (375 r.p.m) according to the manufacturerʹs instructions. A normal saline solution was used for irrigation. The roots were cut longitudinally and the canal walls were examined for debris and smear layer at the apical, middle and coronal level. Results: When using rotary technique, significant superiority was seen in removal of debris (p<0.05). But, the two groups didnʹt have significant difference with reference to smear layer. The three region examined in each group didnʹt have significant differences with regard to debris and smear layer. Conclusion: The rotary technique employed in this study produced cleaner root canal walls than the manual SS K-flexofile instrumentation.