The effectivity of Cone Beam Computed Tomography (CBCT) in dentigerous cyst management: a literature review

Objectives: This review aims to understand the effectiveness of Cone Beam Computed Tomography (CBCT) in the management of dentigerous cysts by looking at the advantages and disadvantages based on the quality of the resulting radiographic images. Review: Based on the literature review that has been carried out on 10 journals were eliminated from 22 journals that had the criteria according to the topic but there was a duplication in the identification results of the initial 50 journals from Pubmed, Google Scholar, ScienceDirect, and EuropePMC, with a range of 2012-2022 using the Boolean Operator Strategy with inclusion criteria developed from PICOS framework, it was found that the CBCT radiographic method is the most widely used method in the management of dentigerous cysts because of the predominance of advantages over disadvantages. This radiographic method is able to produce three-dimensional radiographic images without overlapping structures, distortions, and amplifications at a low cost, although it has weaknesses. Conclusion: CBCT 3D may assess dentigerous cyst lesions effectively by taking into account several considerations and the accuracy of the SOP in its use. This radiography method can provide clear radiographic images without structural overlap, distortion, and amplification at a low cost to confirm the diagnosis and determine the appropriate treatment plan despite the drawbacks as a new result of development technologies in dental radiography

Software applied to oral implantology : update

Software in combination with imaging techniques is used increasingly for diagnosis, planning and treatment in oral implantology. Computer-aided surgery allows a great accuracy in implant positioning to be obtained, taking advantage of the amount of bone available and facilitating minimally invasive surgery. It is a significant aid in determining implant number, location, angle and characteristics. A CT with a radiographic template positioned in the mouth is made for the patient. Data are stored on a CD in DICOM 3 format and then introduced in the computer where implant treatment will be planned, using the chosen software. Navigation improves surgical accuracy through the aid of software based on the images captured from CT or MRI and a surgical instrument tracking system. Infrared light-emitting diodes are connected to rotatory instruments and to the patient?s template. Information is collected by special-purpose cameras, allowing the procedure to be viewed in real time on a monitor. It is useful in situations where an exact implantation is demanded, such as anatomical limitations, little space, atrophic maxillae, sinus lifts or zygomatic implants. Articles reviewed agree in emphasizing the reliability and accuracy of the planning and computer-assisted navigation systems available in the market. Nevertheless, many applications are still in the development phase

Boundary aware reconstruction of scalar fields

pre-printIn visualization, the combined role of data reconstruction and its classification plays a crucial role. In this paper we propose a novel approach that improves classification of different materials and their boundaries by combining information from the classifiers at the reconstruction stage. Our approach estimates the targeted materials' local support before performing multiple material-specific reconstructions that prevent much of the misclassification traditionally associated with transitional regions and transfer function (TF) design. With respect to previously published methods our approach offers a number of improvements and advantages. For one, it does not rely on TFs acting on derivative expressions, therefore it is less sensitive to noisy data and the classification of a single material does not depend on specialized TF widgets or specifying regions in a multidimensional TF. Additionally, improved classification is attained without increasing TF dimensionality, which promotes scalability to multivariate data. These aspects are also key in maintaining low interaction complexity. The results are simple-to-achieve visualizations that better comply with the user's understanding of discrete features within the studied object

Single Camera Spectral Domain Polarization-sensitive Optical Coherence Tomography Using Offset B-scan Modulation

doi:10.1364/OE.18.007281We report a simple implementation to acquire spectral domain polarization-sensitive optical coherence tomography (PSOCT) using a single camera. By combining a dual-delay assembly in the reference arm and offset B-scan in the sample arm, the orthogonal vertical- and horizontalpolarized images were acquired in parallel and spatially separated by a fixed distance in the full range image space. The two orthogonal polarization images were recombined to calculate the intensity, retardance and fast-axis images. This system was easy to implement and capable of acquiring highspeed in vivo 3D polarization-sensitive OCT images

CT Scanning

Since its introduction in 1972, X-ray computed tomography (CT) has evolved into an essential diagnostic imaging tool for a continually increasing variety of clinical applications. The goal of this book was not simply to summarize currently available CT imaging techniques but also to provide clinical perspectives, advances in hybrid technologies, new applications other than medicine and an outlook on future developments. Major experts in this growing field contributed to this book, which is geared to radiologists, orthopedic surgeons, engineers, and clinical and basic researchers. We believe that CT scanning is an effective and essential tools in treatment planning, basic understanding of physiology, and and tackling the ever-increasing challenge of diagnosis in our society

Three-dimensional modeling of the human jaw/teeth using optics and statistics.

Object modeling is a fundamental problem in engineering, involving talents from computer-aided design, computational geometry, computer vision and advanced manufacturing. The process of object modeling takes three stages: sensing, representation, and analysis. Various sensors may be used to capture information about objects; optical cameras and laser scanners are common with rigid objects, while X-ray, CT and MRI are common with biological organs. These sensors may provide a direct or an indirect inference about the object, requiring a geometric representation in the computer that is suitable for subsequent usage. Geometric representations that are compact, i.e., capture the main features of the objects with a minimal number of data points or vertices, fall into the domain of computational geometry. Once a compact object representation is in the computer, various analysis steps can be conducted, including recognition, coding, transmission, etc. The subject matter of this dissertation is object reconstruction from a sequence of optical images using shape from shading (SFS) and SFS with shape priors. The application domain is dentistry. Most of the SFS approaches focus on the computational part of the SFS problem, i.e. the numerical solution. As a result, the imaging model in most conventional SFS algorithms has been simplified under three simple, but restrictive assumptions: (1) the camera performs an orthographic projection of the scene, (2) the surface has a Lambertian reflectance and (3) the light source is a single point source at infinity. Unfortunately, such assumptions are no longer held in the case of reconstruction of real objects as intra-oral imaging environment for human teeth. In this work, we introduce a more realistic formulation of the SFS problem by considering the image formation components: the camera, the light source, and the surface reflectance. This dissertation proposes a non-Lambertian SFS algorithm under perspective projection which benefits from camera calibration parameters. The attenuation of illumination is taken account due to near-field imaging. The surface reflectance is modeled using the Oren-Nayar-Wolff model which accounts for the retro-reflection case. In this context, a new variational formulation is proposed that relates an evolving surface model with image information, taking into consideration that the image is taken by a perspective camera with known parameters. A new energy functional is formulated to incorporate brightness, smoothness and integrability constraints. In addition, to further improve the accuracy and practicality of the results, 3D shape priors are incorporated in the proposed SFS formulation. This strategy is motivated by the fact that humans rely on strong prior information about the 3D world around us in order to perceive 3D shape information. Such information is statistically extracted from training 3D models of the human teeth. The proposed SFS algorithms have been used in two different frameworks in this dissertation: a) holistic, which stitches a sequence of images in order to cover the entire jaw, and then apply the SFS, and b) piece-wise, which focuses on a specific tooth or a segment of the human jaw, and applies SFS using physical teeth illumination characteristics. To augment the visible portion, and in order to have the entire jaw reconstructed without the use of CT or MRI or even X-rays, prior information were added which gathered from a database of human jaws. This database has been constructed from an adult population with variations in teeth size, degradation and alignments. The database contains both shape and albedo information for the population. Using this database, a novel statistical shape from shading (SSFS) approach has been created. Extending the work on human teeth analysis, Finite Element Analysis (FEA) is adapted for analyzing and calculating stresses and strains of dental structures. Previous Finite Element (FE) studies used approximate 2D models. In this dissertation, an accurate three-dimensional CAD model is proposed. 3D stress and displacements of different teeth type are successfully carried out. A newly developed open-source finite element solver, Finite Elements for Biomechanics (FEBio), has been used. The limitations of the experimental and analytical approaches used for stress and displacement analysis are overcome by using FEA tool benefits such as dealing with complex geometry and complex loading conditions

Optimization of X-ray Investigations in Dentistry Using Optical Coherence Tomography

The most common imaging technique for dental diagnoses and treatment monitoring is X-ray imaging, which evolved from the first intraoral radiographs to high-quality three-dimensional (3D) Cone Beam Computed Tomography (CBCT). Other imaging techniques have shown potential, such as Optical Coherence Tomography (OCT).We have recently reported on the boundaries of these two types of techniques, regarding. the dental fields where each one is more appropriate or where they should be both used. The aim of the present study is to explore the unique capabilities of the OCT technique to optimize X-ray units imaging (i.e., in terms of image resolution, radiation dose, or contrast). Two types of commercially available and widely used X-ray units are considered. To adjust their parameters, a protocol is developed to employ OCT images of dental conditions that are documented on high (i.e., less than 10 �m) resolution OCT images (both B-scans/cross sections and 3D reconstructions) but are hardly identified on the 200 to 75 �m resolution panoramic or CBCT radiographs. The optimized calibration of the X-ray unit includes choosing appropriate values for the anode voltage and current intensity of the X-ray tube, as well as the patient’s positioning, in order to reach the highest possible X-rays resolution at a radiation dose that is safe for the patient. The optimization protocol is developed in vitro on OCT images of extracted teeth and is further applied in vivo for each type of dental investigation. Optimized radiographic results are compared with un-optimized previously performed radiographs. Also, we show that OCT can permit a rigorous comparison between two (types of) X-ray units. In conclusion, high-quality dental images are possible using low radiation doses if an optimized protocol, developed using OCT, is applied for each type of dental investigation. Also, there are situations when the X-ray technology has drawbacks for dental diagnosis or treatment assessment. In such situations, OCT proves capable to provide qualitative images