The purpose of this study was to compare the sealing ability of gray mineral trioxide aggregate (GMTA), white MTA (WMTA), and both white and gray Portland cement as furcation perforation repair materials. A total of 120 human mandibular first molars were used. After root canal obturation and preparation of furcal perforations the specimens were randomly divided into four groups of 25 teeth each...

OBJECTIVES The aim of the present study was to determine radiographically the different reasons and problems of endodontic treatment failure. METHODS The periapical radiographs of 100 patients with one hundred teeth (130 root canals) were examined to identify the problems and failures of endodontic treatment. The various reasons of failure that is under filling, poor filling, over filling and...

Root canal and furcal perforations are causes of endodontic therapy failure and different materials that stimulate tissue mineralization have been proposed for perforation treatment. In the first case, a patient presented tooth 46 with unsatisfactory endodontic treatment and a periapical radiographic lesion. A radiolucent area compatible with a perforating internal resorption cavity was found i...

in the past, rock slope stability analysis were performed either graphically or using a hand-held calculator, but nowadays there are variety of slope stability analysis which can be used according to the field condition and potential failure mode. in 2-d analysis, effect of convex and concave walls are neglected, however concave slopes are believed to be more stable than straight walls due to t...

quantification of arterial elasticity and its dependency to age is considered in this paper. we use radiofrequency (rf) signals fromcarotid artery ultasonography to evaluate this dependency. blood pressure, blood flow, and tethering to surrounding tissue are the maincauses of the motion of the carotid wall. tracking carotid artery wall motion from a series of ultrasound b‑mode images is challen...

with the growing population and density in metropolitan areas, higher tendency to live in high-rise buildings, and increasing demand for parking lots, it seems necessary to excavate soil to construct underground spaces. during excavation work, as the height of the wall increases, special care should be taken to the wall stabilization to avoid any consequent damage including extensive property d...

introduction: the horizontal bony canal in the lateral maxillary wall is the site of anastomosis between the arterial branches from the posterior superior alveolar artery (psaa) and the infraorbital artery. this anatomic structure is known as the ‘alveolar antral artery’.   materials and methods: we performed a literature review. the anatomic location of the alveolar antral artery in the latera...

an important issue in power generation and petrochemical industries is the monitoring of pipe wall thickness and corrosion/erosion rate. the pipes are usually subject to erosive and/or corrosive environments and any failure could be catastrophic. while periodic manual ultrasonic thickness measurement is the common practice in many industries, in certain cases, where higher accuracies are requir...

Hydatid disease (HD) is an infectious disease caused by echinococcosis. Hydatid cyst (HC) most commonly invades the liver (60-70%) and the lungs (20-25%). However, other parts of the body and even unusual locations can be infected, mimicking a benign lesion that could be easily missed. Primary HC of the chest wall is extremely rare, even in countries where echinococcosis is endemic. We he...