conclusion no significant differences were found among observers or voxel sizes, with high az results reported for all groups. results no significant differences were found among observers or voxel sizes, with high average z (az) results being reported for all groups. both intra- and inter-observer agreement values were relatively better for 3d accuitomo 170 images than the images from newtom 3...

background: field matching problems in abutting electron fields can be managed by using spoilers. objective: the aim of this study was to design a monte carlo framework for the assessment of spoiler application in abutting electron fields. methods: a siemens primus treatment head was simulated for a 5 mev electron beam using beamnrc and dosxyznrc, egsnrc user codes. validation of beam model was...

background and aims. with the introduction of cone beam computed tomography (cbct) in dentistry, a question has been raised whether the technique significantly increases the diagnostic accuracy in comparison with other techniques or not. therefore, the present study was undertaken to assess the accuracy of cbct modality in detecting proximal carious lesions as compared to conventional periapica...

background cone beam computed tomography (ct) has recently become effective for oral and maxillofacial imaging. objectives the aim of this study was to assess the knowledge of dentists regarding cone beam computed tomography. materials and methods in this descriptive cross sectional study, a questionnaire regarding cone-beam computed tomography (cbct) was distributed amongst 100 dentists (gener...

the price of single point diamond tools with a sharp tip is very high due to complex machining process and highly expensive machining equipments. yet, the performance is not quite satisfactory. in this paper, we have presented a very simple and cost effective machining process for the sharpening and polishing of diamond stylus using low energy reactive ion beam machining (ribm). in our method, ...

introduction: a study model is a precise three dimensional replica of patient’s dentition and plays an important role in treatment planning. many digital multi-media applications have become available to the clinician and his or her staff to facilitate standard procedures in practice and management. the aim of this study is to evaluate reliability and validity of dental measurement made on digi...

parotid stafne bone defect is a very rare and infrequent variant, which is located on the buccal or lingual surface of the mandibular ascending ramus. in this paper, a case of parotid stafne defect, which was incidentally discovered during dental radiographic examination, is reported. this bone defect was observed as a lucent oval-shaped defect on the lingual aspect of the right mandibular ramu...

introdouction: the aim of this study was to compare information regarding pharyngeal airway sizes in adolescent subjects with different malocclusion classes obtained from lateral cephalograms and 3–dimensional (3d) cone-beam computed tomography (cbct) scans. materials and methods: in this prospective cross-sectional study, cbct scans and lateral cephalograms of 35 subjects, taken within one wee...

post-harvest management of potatoes is a major challenge in iran. approximately 30% of the harvest is lostafter a few months of storage. the chemical methods for long term storage are not adequate to controldeterioration and also produce undesirable side effects. to address this issue, a study on radiationpreservation of potatoes was carried out. agria potato bulbs were irradiated using beta be...

air pollutants from iron and steel making operations have historically been an environmental concern. the factory located at ahwaz, iran, has two production lines namely, 630 and 650, which produce iron parallel edge. the objective of the study is to determine indoor respiratory particulate matter (rpm) and feo concentrations and their comparison with niosh standards. this is a cross–sectiona...