introduction: full crown preparation may have adverse effects on pulp tissue. in this study, the effect of full-crown preparation on intact versus inflamed pulp tissue was studied. methods: fifteen healthy mature cats were randomly selected for this study. the study was performed on four canine teeth of each cat. cats were anesthetized and then radiographs were taken from the canine teeth. clas...

production of fe-c alloy powders by mechanical alloying was studied. fe and graphite elemental powdermixtures containing 0.8 and 1.5wt.% graphite were mechanically alloyed using a planetary ball mill. thestructural changes of powder particles during mechanical alloying were studied by x-ray diffractometery,scanning electron microscopy and microhardness measurements. for both compositions, mecha...

objectives : cleaning and shaping of the root canal system is an important step in endodontic therapy. new instruments incorporate new preparation techniques that can improve the efficacy of cleaning and shaping. the aim of this study was to compare the efficacy of mtwo and race rotary file systems in straightening the canal curvature using only one file or the conventional method. materials an...

1 ABSTRACT The dissemination of critical information and the synchronization of coordinated activities are critical problems in geographically separated, large-scale, software development. While these problems are not insurmountable, their solutions have varying trade-oos in terms of time, cost and eeectiveness. Our previous studies have shown that the inspection interval is typically lengthene...

the aim of ideal canal preparation is to prevent iatrogenic aberrations such as transportation. the aim of this study was to evaluate the root canal transportation by reciproc file with and without glide path.thirty acrylic-resin blocks with a curvature of 60° and size#10 (2% taper) were assigned into two groups (n= 15). in group 1, the glide path was performed using stainless steel k-files siz...

kinetic parameters of the ammonolysis reaction of dichloroethane in nonaqueous media are studied and the optimum reaction conditions are reported. a suitable reactor for running the reaction under high pressure in the range of 50 to 500 °c is designed. kinetic behaviours of the system is studied and other reaction parameters such as rate constant, kinetic order, and activation energy are determ...

introduction: the purpose of this in-vitro study was to compare shaping ability of niti rotary mtwo and flexmaster with stainless steel hand k-flexofile in curved root canals of extracted teeth. materials and methods: mesiobuccal canals of 45 mandibular molar teeth were balanced into three groups of 15 each, with respect to the schneider angle, canal access angle, height, dis-tance and radius o...

materials and methods: one hundred and thirty five mesial root canals of mandibular first and second molar teeth were selected. access cavities were prepared. after inserting a k-file size #10 into each canal, radiographs were taken. canal curvature was determined by measuring the schneider angle, canal access angle, as well as the canal radius, length, height and curvature starting distance on...

in present study we studied using green routes for microwave assisted synthesis of alumina nanoparticles from aluminum nitrate. it was revealed that when plant extracts are used, no specific stabilizer is needed. structural characterization of nanoparticles was studied using x-ray diffraction that showed semi-crystalline structure for two of plant extracts, other xrd patterns had no significant...