نتایج جستجو برای: beam computed tomography

تعداد نتایج: 366028  

Journal: :journal of dental research, dental clinics, dental prospects 0
farzad esmaeili masume johari pezhman haddadi mehdi vatankhah

background and aims. at present, cone beam computed tomography (cbct) has become a substitute for computed tomography (ct) in dental procedures. the metallic materials used in dentistry can produce artifacts due to the beam hardening phenomenon. these artifacts decrease the quality of images. in the present study, the number of artifacts as a result of beam hardening in the images of dental imp...

شریفی, ساناز, ورشوساز, مسعود,

Background: Paranasal sinus disease is one of the most common problems of patients that refer to ENT centers. Adding to clinical examination imaging plays an important role in diagnosis and treatment. Also the imaging of paranasal sinuses is necessary before surgery. Although computed tomography is the modality of choice for these areas, it has some disadvantages which the most important one is...

Journal: :journal of dental research, dental clinics, dental prospects 0
tahmineh razi assistant professor, department of oral and maxillofacial radiology tabriz university of medical science mahdi niknami assistant professor, department of oral and maxillofacial radiology tehran university of medical science fakhri alavi ghazani post graduate student department of oral and maxillofacial radiology tabriz university of medical science

background and aims. cone-beam computed tomography (cbct) is an imaging system which has many advantages over computed tomography (ct). in ct scan, hounsfield unit (hu) is proportional to the degree of x-ray attenuation by the tissue. in cbct, the degree of x-ray attenuation is shown by gray scale (voxel value). the aim of the present study was to investigate the relationship between gray scale...

Journal: :journal of dentistry, tehran university of medical sciences 0
masoud varshowsaz sepideh goorang sara ehsani zeynab azizi sepideh rahimian

objectives: bone quality and quantity assessment is one of the most important steps in implant treatment planning. different methods such as computed tomography (ct) and recently suggested cone beam computed tomography (cbct) with lower radiation dose and less time and cost are used for bone density assessment. this in vitro study aimed to compare the tissue density values in hounsfield units (...

Journal: :iranian journal of radiology 0
solmaz valizadeh department of radiology, school of dentistry, shahid beheshti university of medical sciences, tehran, iran; dental research center, research institute of dental sciences, shahid beheshti university of medical sciences, tehran, iran hamidreza pouraliakbar dental research center, research institute of dental sciences, shahid beheshti university of medical sciences, tehran, iran leila kiani rajaie cardiovascular medical and research center, iran university of medical sciences, tehran, iran yaser safi department of radiology, school of dentistry, shahid beheshti university of medical sciences, tehran, iran leila alibakhshi department of radiology, school of dentistry, shahid beheshti university of medical sciences, tehran, iran; department of radiology, school of dentistry, shahid beheshti university of medical sciences, tehran, iran. tel: +98-2122907040, fax: +98-2188804037

conclusions ultrasound is recommended as the first choice when fb is located within the superficial soft tissues with no bone around it. in case of penetration of fb into deeper tissues or beneath bone, ct or cbct are recommended. otherwise, considering lower dose, cbct is preferred over ct. we can use mri if the fb is not ferromagnetic. however, ct is the first choice in emergency situations b...

Journal: :iranian endodontic journal 0
yaser safi mohammad mehdi aghdasi fatemeh ezoddini-ardakani samira beiraghi zahra vasegh

introduction: vertical root fracture (vrf) is common in endodontically treated teeth. conventional and digital radiographies have limitations for detection of vrfs. cone-beam computed tomography (cbct) offers greater detection accuracy of vrfs in comparison with conventional radiography. this study compared the effects of metal artifacts on detection of vrfs by using two cbct systems. methods a...

Journal: :journal of dental research, dental clinics, dental prospects 0
arash dabbaghi nafiseh nikkerdar oral and maxillofacial radiology department, dental school, kermanshah university of medical sciences soheyla bayati amin golshah orthodontics department, dental school, kermanshah university of medical sciences

odontogenic myxoma (om) is an infiltrative benign bone tumor that occurs almost exclusively in the facial skeleton. the radiographic characteristics of odontogenic myxoma may produce several patterns, making diagnosis difficult. cone-beam computed tomography (cbct) may prove extremely useful in clarifying the intraosseous extent of the tumor and its effects on surrounding structures. here, we r...

Journal: :iranian endodontic journal 0
ali soleymani nafiseh namaryan ehsan moudi ali gholinia

introduction: the present study was conducted to assess the morphology of mandibular canines using cone-beam computed tomography (cbct) in a north iranian population. methods and materials: for the morphological assessment of mandibular canines, 150 cbct images taken from patients for different reasons were used. the mandibular canines were examined in sagittal, coronal and axial dimensions. th...

Journal: :journal of dentistry, tehran university of medical sciences 0
leila khojastepour department of oral and maxillofacial radiology, school of dentistry, shiraz university of medial science, shiraz, iran shirin kolahi department of oral and maxillofacial radiology, school of dentistry, shiraz university of medial science, shiraz, iran nazi panahi department of oral and maxillofacial radiology, school of dentistry, shiraz university of medial science, shiraz, iran abdolaziz haghnegahdar department of oral and maxillofacial radiology, school of dentistry, shiraz university of medial science, shiraz, iran

objectives: differential diagnosis of bifid mandibular condyle (bmc) is important, since it may play a role in temporomandibular joint (tmj) dysfunctions and joint symptoms. in addition, radiographic appearance of bmc may mimic tumors and/or fractures. the aim of this study was to evaluate the prevalence and orientation of bmc based on cone beam computed tomography (cbct) scans.   materials and...

Journal: :journal of dentistry, tehran university of medical sciences 0
mehrdad panjnoush yasaman kheirandish pooneh mohseni kashani hoorieh bashizadeh fakhar farzan younesi maysa mallahi mallahi

objectives: the aim of this study was to assess the effect of tube current, kilovoltage peak (kvp), metal type, and the position of metal objects on metal artifacts in cone-beam computed tomography (cbct) images. materials and methods: titanium and cobalt-chromium rods were fabricated and placed in a dry human mandible. samples were scanned using a promax 3d cbct unit with different milli-amper...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید