introduction: the aim of this study was to verify the effect of alternating 2.5% sodium hypochlorite (naocl) and 17% ethylenediaminetetraacetic acid (edta) on the smear layer removal from root canal surfaces. methods and materials: a total of 15 single-rooted human teeth, instrumented with protaper files, were randomly distributed in 3 groups. in group 1 ( n =7) the canals were irrigated with 1...

introduction: this study aimed to assess the scanning electron microscope (sem) analysis of tooth surface irradiated by erbium:yttrium–aluminum–garnet (er:yag) laser with various parameters. methods: number of 25 extracted human third molars free of caries were used in this study. the teeth were put into 5 groups for laser irradiation as follows: group 1 (power: 0.5 w, energy: 50 mj); group 2 (...

background and objectives: biological scaffold resources composed of extracellular matrix (ecm) have been shown to make easy the practical remodeling of various tissues in both animal and human studies. the goal of current study was to make sheet form of ecm from sheep’s urinary bladder. methods: ecm was extracted from sheep’s urinary bladder according to standard method. scanning electron mic...

the normal and lateral line cycloid scales of the native species garra rossica (nikol’skii, 1900), one of the most common and poorly known cyprinid fish in south-eastern iran have been subjected to the scanning electron microscopy technique in order to study their detailed structure. normal scale below the dorsal fin showed a clearcut demonstration between the anterior and posterior region with...

the aim of the present study was to investigate the light and electron microscopic structure of the tongue in white-eared bulbul (pycnonotus leucotis). six adult white-eared bulbul (3 males and 3 females) in shahrekord district were used in the investigation. samples of the apex, body and root of the tongue were prepared routinely for light and electron microscopic study. results showed that th...

introduction: bacteria and their byproducts are major etiologic factors in endodontic diseases. prevention or reduction of root canal bacterial contamination is the main aim of endodontic treatment. the purpose of this in vitro study was to evaluate the effect of size and taper of master apical file (maf) in reducing bacteria from the apical third of the curved canals using a quantitative scann...

introduction: in this experimental study, the amount of smear layer (sl) remnants in curved root canals after chemomechanical instrumentation with two engine-driven systems or hand instrumentation was evaluated. methods and materials: forty-eight mesiobuccal roots of mandibular first molars with curvatures ranging between 25 and 35 degrees (according to schneider’s method) were divided into thr...

in this research, the effect of catalyst type on the cnts synthesis was investigated. the carbonnanotubes (cnts) were produced on stainless steel substrates and two of catalyst with differentcharacteristics by using thermal chemical vapor deposition (tcvd) method. the catalysts have theimportant role for the growth carbon nanotubes (cnts). acetylene gas (c2h2) diluted by nh3 wasused as the reac...

in recent years, it has become evident that it is necessary to systematically and accurately define particle characteristics in order to understand the potential toxicity of nanoparticles to biological systems. the properties that need to be emphasized are size, shape, dispersion, doping, aggregation, functionalization, physical and chemical properties, surface area, and surface chemistry. rout...