%0 Journal Article %A Gheshlaghi- Azar, N %A Javad zadeh Haghighat, AS %T Comparative Study on Degree of Root Canal Transportation Using Two Rotary Systems of Protaper, Profile 0.04 Taper and Hand K- Flexofiles in a In Vitro Condition %J Journal of Guilan University of Medical Sciences %V 13 %N 51 %U http://journal.gums.ac.ir/article-1-658-en.html %R %D 2004 %K ٌRoot Canal Prepration, Root Canal Therapy, %X Abstract Introduction : Root canal preparation is one of the most important stages of endodontic treatment. It seems that rotary NiTi files are efficient instruments in root canal preparation. Objective: This in vitro study was designed to assess the degree of canal transportation, resulting from instrumentation by a new rotary system (protaper) and to compare it with rotary profile 0.04 taper series 29 system and hand K- flexofiles in a Step- back manner. Materials and Methods: Thirty six mesiobuccal canals of extracted human mandibular molars were instrumented in three groups by each of these methods respectively. Rotary systems were used in a crown- down manner according to the manufacture’s instruction, and stainless steel K- flexofiles were used in a conventional step- back method. Pre- and postoperative X- rays were taken, projected and degree of canal curvature was determined according to the schneider method. The difference of pre- and postoperative canal curvature was evaluated with ANOVA and student tests. Results: The results of statistical analysis indicated that the degree of canal transportion in protaper group was statistically less than that in K- flexofile group that this difference was statistically significant(P %> http://journal.gums.ac.ir/article-1-658-en.pdf %P 78-85 %& 78 %! %9 Research %L A-10-36-499 %+ %G eng %@ 2383-4307 %[ 2004