objectives: this study aimed to assess the effect of voxel size and object location in the field of view (fov) on diagnostic accuracy of cone beam computed tomography (cbct) for detection of simulated bone defects. materials and methods: in this in vitro study, bone defects were drilled in four sections of a dry human mandible. bone blocks were fixed on a platform parallel to the horizontal pla...

root canal anatomy diversity and aberrations are common especially in permanent dentition. a thorough understanding of the basic root canal anatomy and its diversities are necessary for successful endodontic treatment. mandibular second premolars are usually single-rooted and have one root canal. incidence of three separate root canals in this tooth is quite rare and taurodontism with three sep...

A cone-beam algorithm which provides a practical implementation of B D Smith's cone-beam inversion formula is presented. For a cone-beam vertex orbit consisting of a circle and an orthogonal line. This geometry is easy to implement in a SPECT system, and it satisfies the cone-beam data sufficiency condition. The proposed algorithm is in the form of a convolution-back projection, and requires a ...

The cone-beam approach for image reconstruction attracts an increasing attention in various applications, especially medical imaging. Previously, the traditional practical cone-beam reconstruction method, the Feldkamp algorithm, was generalized into the case of spiral/helical scanning loci with equispatial cone-beam projection data. In this paper, we formulated the generalized Feldkamp algorith...

Tuy's cone-beam inversion formula was modified to develop a cone-beam reconstruction algorithm. The algorithm was implemented for a cone-beam vertex orbit consisting of a circle and two orthogonal lines. This orbit geometry satisfies the cone-beam data sufficiency condition and is easy to implement on commercial single photon emission computed tomography (PECT) systems. The algorithm, which con...

resorption of tooth structures can occur as a result of physiological, pathological, and idiopathic factors. early diagnosis and appropriate treatment can prevent its serious complications. this case report presents surgical endodontic management of a trauma-induced perforating external root resorption, which was diagnosed with the help of cone beam computed tomography. following root canal tre...

maxillary sinus aplasia and hypoplasia are rare conditions that can cause symptoms such as headaches and voice alteration. the majority of patients are asymptomatic, but these conditions must be noticed for importance of differential diagnosis such as infection and neoplasms. conventional radiographs could not differentiate between infl ammatory mucosal thickening, neoplasm, and hypoplasia of t...

In this paper, we present a new algorithmic paradigm for cone-beam image reconstruction. The new class of algorithms, referred to as cone-beam reconstruction by moving frames, enables numerical implementation of exact cone-beam inversion using its intrinsic geometry. In particular, our algorithm allows a 3-D discrete approach to the differentiation-backprojection operator on the curved manifold...