BACKGROUND Complete removal of old filling material during root canal retreatment is fundamental for predictable cleaning and shaping of canal anatomy. Most of the retreatment methods tested in earlier studies have shown inability to achieve complete removal of root canal filling. Therefore the aim of this investigation was to assess the efficacy of three different rotary nickel titanium retrea...

t u C T c bstract he purpose of this study was to evaluate the topogaphy of new and used ProTaper rotary nickel-titanium NiTi) instruments by using atomic force microscope. our new and four used size S1, S2, F1, and F2 instruents were selected for this study. New and used nstruments were analyzed on 11 points along a 3-mm ection at the tip of the instrument. Quantitative meaurements according t...

INTRODUCTION The bending and torsional properties of thermomechanically treated K3XF (SybronEndo, Orange, CA) nickel-titanium instruments in relation to their phase transformation behavior were evaluated. METHODS NiTi instruments K3 (SybronEndo) and K3XF, both in sizes 25/.04 and 40/.04, were examined by differential scanning calorimetry and X-ray diffraction. The metal composition was determ...

OBJECTIVES The aim of the present study was to investigate the incidence of deformation and fracture of twisted file adaptive nickel-titanium instruments after repeated clinical use and to identify and check whether the three instruments within the small/medium sequence showed similar or different visible signs of metal fatigue. MATERIAL AND METHODS One-hundred twenty twisted file adaptive (T...

INTRODUCTION The aim of this study was to investigate the relationship between fatigue life and resonance frequency (RF) of various types of nickel-titanium (NiTi) rotary instruments. In addition, the influence of NiTi instruments with different manufacturing methods on cyclic loading was evaluated by using RF as a parameter. METHODS Twenty-eight ProFile instruments and 10 Twisted File instru...

introduction: disinfection and subsequent obturation of the root canal space require adequate mechanical enlargement of the canals. the purpose of this in vitro study was to compare the shaping ability of mtwo, race and medin rotary instruments during the preparation of curved root canals. materials and methods: sixty mesiobuccal root canals of mandibular molars with severe curvatures between 2...

Root canal shaping is of utmost importance in the success of root canal treatment. Numbers of systems available are effective for shaping; accounting from stainless steel hand files to nickel-titanium rotary files to the new single file system concept. Single file technique is developed for shaping vast majority of canals, regardless of their length, diameter or curvature. Therefore, single use...

AIM To compare the cleaning effectiveness and shaping ability of Mtwo, K3, and RaCe nickel-titanium rotary instruments during the preparation of curved root canals in extracted human teeth. METHODOLOGY A total of 60 root canals of mandibular and maxillary molars with curvatures ranging between 25 degrees and 35 degrees were divided into three groups of 20 canals. Based on radiographs taken pr...

AIM To determine whether the following can be sterilized by autoclaving - endodontic sponges, rotary nickel-titanium (NiTi) instruments within endodontic sponges, and rotary NiTi instruments with rubber stoppers. METHODOLOGY Sixty-four samples of eight different endodontic sponges (n = 512) were placed into brain heart infusion broth (BHI) for 72 h. An aliquot of this was then spread onto hor...