Additional dentition images are needed because the dentitions distorted in cone-beam computed tomography (CBCT) due to streak artifacts and non-uniformity of x-ray beam. The purpose this study is evaluate feasibility improving image CBCT scan with intraoral scanner instead plaster models. Maxilla from models, two scanners, 20 patients aged 12 18 were used study. With one full arch was scanned b...

OBJECTIVE To assess the breast dose during a routine thoracic cone-beam CT (CBCT) check with the efforts to explore the possible dose reduction strategy. MATERIALS AND METHODS Metal oxide semiconductor field-effect transistor (MOSFET) dosimeters were used to measure breast surface doses during a thorax kV CBCT scan in an anthropomorphic phantom. Breast doses for different scanning protocols a...

This case report describes a unique C-shaped mandibular second premolar with four canals and three apical foramina and its endodontic management with the aid of cone-beam computer tomography (CBCT). C-shaped root canal morphology with four canals was identified under a dental operating microscope. A CBCT scan was taken to evaluate the aberrant root canal anatomy and devise a better instrumentat...

As part of the quality assurance programme in a dental radiology referral centre, the reasons for taking cone beam CT (CBCT) images were analysed and the volume sizes of the field of view (FOV) were noted. Eighty CBCT scans were carried out in the period examined. Implant planning accounted for 40% of the scans, 26% were for assessment of lesions of endodontic origin, 19% for assessing impactio...

BACKGROUND To improve the delivery of radiotherapy in gynecologic malignancies and to minimize the irradiation of unaffected tissues by using daily kilovoltage cone beam computed tomography (kV-CBCT) to reduce setup errors. METHODS Thirteen patients with gynecologic cancers were treated with postoperative volumetric-modulated arc therapy (VMAT). All patients had a planning CT scan and daily C...

PURPOSE Longitudinal coverage of CBCT, which is 17 cm for head scan and 15.5 cm for body scan, is not enough to cover the entire PTV for over 90% of head/neck and gastrointestinal/genitourinary/gynecologic patients if lymph nodes are involved. Helical CBCT, which was accomplished using external beam LINAC in its research mode, is one promising way to extend the CBCT longitudinal coverage. Aim o...

ID: 14214 Title: A novel scatter reduction and correction method to improve cone-beam CT (CBCT) image quality Purpose: To develop a novel scatter reduction and correction method to improve the CBCT image quality for IGRT applications. Method and Materials: A one-dimensional grid composed of lead with equal interspacing was positioned between the x-ray source and the imaging object during CBCT a...

OBJECTIVE To measure surface skin dose from various cone-beam computed tomography (CBCT) scanners using point-dosimeters. MATERIALS & METHODS A head anthropomorphic phantom was used with nanoDOT optically stimulated luminescence (OSL) dosimeters (Landauer Corp., Glenwood, IL) attached to various anatomic landmarks. The phantom was scanned using multiple exposure protocols for craniofacial eva...

Cone-beam computed tomography (CBCT) images suffer from poor image quality, in a large part due to contamination from scattered X-rays. In this work, a Monte Carlo (MC)-based iterative scatter correction algorithm was implemented on measured phantom data acquired from a clinical on-board CBCT scanner. An efficient EGSnrc user code (egs_cbct) was used to transport photons through an uncorrected ...

PURPOSE We evaluated whether measurements on conventional cephalometric radiographs are comparable to measurements on cone-beam computed tomography (CBCT)-constructed cephalometric radiographs taken from human skulls. MATERIALS AND METHODS The CBCT scans and conventional cephalometric radiographs were made using 40 dry skulls. With I-Cat Vision software (Imaging Sciences International, Inc, H...