Download or read book Accuracy of Alveolar Bone Measurements Using Cone Beam Computed Tomography Compared with Direct in Vivo Measurements written by Vanessa N.. Browne and published by . This book was released on 2015 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Accuracy of Alveolar Bone Measurements from Cone Beam Computed Tomography at Multiple Parameters written by Lane C. Cook and published by . This book was released on 2011 with total page 122 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Accuracy and Reliability of Cone Beam Computed Tomography for Measurement of Alveolar Bone Height and Detection of Bony Dehiscences and Fenestrations written by Cynthia C. Leung and published by . This book was released on 2009 with total page 186 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Accuracy of Cone Beam Computed Tomography in Measuring Alveolar Bone Height and Detecting Dehiscences and Fenestrations in Patients Undergoing Periodontal Surgery written by Megan E. Miller and published by . This book was released on 2013 with total page 182 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Factors Affecting Alveolar Bone Height Measurements from CBCT Images written by Ryan LaDell Wood and published by . This book was released on 2012 with total page 50 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Objectives: Cone beam computed tomography (CBCT) is routinely used to measure alveolar bone dimensions. This study investigated factors likely affecting the accuracy of such measurements. Methods: Marker holes, apical to maxillary and mandibular molar roots, and mesio-distal molar occlusal reference grooves were created in fresh pig heads (n=26 quadrants), followed by CBCT scans at 0.4 and 0.2 mm voxel sizes before and after soft tissue removal. Subsequently, bucco-lingual sections bisecting the marker holes were cut, from which physical alveolar bone height and thickness were measured. Two blinded raters, using Dolphin 3D and OsiriX software, independently collected alveolar bone height measurements from CBCT images. Differences between CBCT and physical measurements (DCBCT-Phy) were calculated. The mean DCBCT-Phy and limit of agreement (LOA, ±1.96SD) for each factor were depicted by Bland-Altman methods. The influence of each factor was examined by repeated measures ANOVAs. Results: The rater factor affected the mean CBCT measurements in both jaws, with mean DCBCT-Phy from a more-experienced rater significantly (p0.05) closer to "0" than from a less-experienced rater, while their LOA ranges were similar (Maxilla, 0.17mm±2.09mm vs.-0.48mm±2.02mm; Mandible, 0.01mm±1.04mm vs.-0.70mm±1.21mm). The software factor also affected the mean CBCT measurements in both jaws, with mean DCBCT-Phy from Osirix significantly (p
Download or read book Cone Beam Computed Tomography in Endodontics written by Shanon Patel and published by Quintessenz Verlag. This book was released on 2019-09-16 with total page 401 pages. Available in PDF, EPUB and Kindle. Book excerpt: In recent years, cone beam computed tomography (CBCT) has become much more widely available and utilised in all aspects of dentistry, including endodontics. Cone Beam Computed Tomography in Endodontics is designed to inform readers about the appropriate use of CBCT in endodontics, and enhance their clinical practice with this exciting imaging modality.
Download or read book Comparative Linear Accuracy and Reliability of Cone Beam CT Derived 2 dimensional Images and Conventional Lateral Cephalometric Images Using Photostimulable Storage Phosphors written by Mazyar Moshiri and published by . This book was released on 2008 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of this project was to compare the accuracy and precision of linear measurements made on conventional lateral cephalograms (LC) and simulated LC using cone-beam computed tomography (CBCT) to direct measurements on dentate skulls. The linear distances for 5 mid-sagittal and 4 bilateral measurements between anatomical landmarks on 22 skulls were measured by two observers. The skulls were imaged using a CBCT scanner at 4 scan settings: high resolution (0.2mm) and normal resolution (0.4mm) at 20-sec (306 projections) and 40-sec scans (612 projections). Three simulated LC were generated: Ray sum image reconstructions of the maximum thickness mid-sagittal multiplanar projections, a single frame basis projection, and the scout image. LCs were acquired using a storage phosphor system. Projection images were exported into a cephalometric analysis program and linear measurements determined. Analyses were repeated three times and statistically compared to measured anatomic truth using repeated measures general linear model (p [less than or equal to] 0.05). The mean absolute error was used as an index of precision. While there were statistical differences between skull and modality measurements for 6 of the nine measurements, there were no overall differences between LC and CBCT derived image measurements irrespective of method of construction. CBCT imaging provides clinically reliable 2D simulation images however, dose considerations demand that evidence-based selection criteria should be developed for CBCT in orthodontics that take into account the ALARA principle.
Download or read book Facial Alveolar Bone Wall Width written by Ahmed Khaled Ahmed Abdin Zekry and published by . This book was released on 2017-01-26 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation, "Facial Alveolar Bone Wall Width: a Cone Beam Computed Tomography (CBCT) Study in Asians" by Ahmed Khaled Ahmed Abdin, Zekry, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. Abstract: Background: The width of the facial alveolar bone wall is crucial for long term successful esthetic outcomes of implants immediately placed into extraction sockets. A threshold of 2 mm is recommended to minimize buccal vertical bone resorption. Aim: To assess the width of the facial alveolar bone wall using cone-beam computed tomography images (CBCT). Methods: Retrospective CBCT images were acquired from a representative sample of Asians using the i-CAT(R) classic system with a 0.4 mm voxel size. At random, 200 CBCT images were selected according to predefined criteria. The DICOM file was imported into the i-Cat Vision(R) software. In the panoramic screen, the middle of each tooth was selected and, in the sagittal window, the middle cross section was selected for performing the measurements using a computer. The vertical distance from the alveolar crest (BC) - CEJ was measured. The width of the facial alveolar bone wall was measured at three locations: 1, 3, and 5 mm apical to BC. Descriptive statistics, frequency analyses, and multi-level comparisons were performed. Results: The sample consisted of 74 males and 126 females (mean age of 37.2 years; range 17-82 years). A total of 3618 teeth were assessed. There was no significant difference between the values of right and left sides, or between genders. However, statistically significant differences were observed between age groups at all levels. The distance from CEJ-BC varied from 0.4 to 4mm, with an overall tendency to increase with age. The mean width of the facial alveolar bone wall at anterior teeth was 0.9 mm and increased towards posterior regions. Rarely, a width of 2 mm was yielded (0.6-1.8 % for anterior teeth, 0.7- 30.8 % for posterior teeth). At a 5mm distance from BC, minimal widths of facial alveolar bone were identified for the anterior teeth. The frequency of dehiscence ranged from 9.9- 51.6 % for anterior and 3.1- 53.6 % for posterior teeth, respectively. Conclusion and clinical implications: A thin facial alveolar bone wall was usually present in both jaws. Hence, for most patients, adjunctive bone augmentation may be needed when installing implants in areas of esthetic concern. DOI: 10.5353/th_b4839566 Subjects: Facial bones - Tomography Teeth - Tomography
Download or read book A Grey level Assisted Method for CBCT Alveolar Bone Height Measurements written by Soumya Padala and published by . This book was released on 2014 with total page 83 pages. Available in PDF, EPUB and Kindle. Book excerpt: Conclusion: Compared to the vision-based method, an interactive grey level assisted method can be used to measure alveolar bone height with superior reliability and at least comparable accuracy.
Download or read book Comparative Linear Accuracy and Reliability of Cone Beam CT Derived 2 dimensional and 3 dimensional Images Constructed Using an Orthodontic Volumetric Rendering Program written by Danielle R. Periago and published by . This book was released on 2007 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of this project was to compare the accuracy and reliability of linear measurements made on 2D projections and 3D reconstructions using Dolphin 3D software (Chatsworth, CA) as compared to direct measurements made on human skulls. The linear dimensions between 6 bilateral and 8 mid-sagittal anatomical landmarks on 23 dentate dry human skulls were measured three times by multiple observers using a digital caliper to provide twenty orthodontic linear measurements. The skulls were stabilized and imaged via PSP digital cephalometry as well as CBCT. The PSP cephalograms were imported into Dolphin (Chatsworth, CA, USA) and the 3D volumetric data set was imported into Dolphin 3D (Version 2.3, Chatsworth, CA, USA).Using Dolphin 3D, planar cephalograms as well as 3D volumetric surface reconstructions were (3D CBCT) generated. The linear measurements between landmarks of each three modalities were then computed by a single observer three times. For 2D measurements, a one way ANOVA for each measurement dimension was calculated as well as a post hoc Scheffe multiple comparison test with the anatomic distance as the control group. 3D measurements were compared to anatomic truth using Student's t test (P [less than or equal to] 50.05). The intraclass correlation coefficient (ICC) and absolute linear and percentage error were determined as indices of intraobserver reliability. Our results show that for 2D mid sagittal measurements that Simulated LC images are accurate and similar to those from PSP images (except for Ba-Na), and for bilateral measurements simulated LC measurements were similar to PSP but less accurate, underestimating dimensions by between 4.7% to 17%.For 3D volumetric renderings, 2/3 rd of CBCT measurements are statistically different from actual measurements, however this possibly is not clinically relevant.
Download or read book Accuracy and Reliability of Buccal Bone Height and Thickness Measurements from Cone beam Computed Tomography Imaging written by Adam M. Timrock and published by . This book was released on 2010 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Image Analysis for Trabecular Bone Properties on Cone Beam CT Data written by Eva Klintström and published by Linköping University Electronic Press. This book was released on 2017-10-20 with total page 73 pages. Available in PDF, EPUB and Kindle. Book excerpt: Trabecular bone structure as well as bone mineral density (BMD) have impact on the biomechanical competence of bone. In osteoporosis-related fractures, there have been shown to exist disconnections in the trabecular network as well as low bone mineral density. Imaging of bone parameters is therefore of importance in detecting osteoporosis. One available imaging device is cone-beam computed tomography (CBCT). This device is often used in pre-operative imaging of dental implants, for which the trabecular network also has great importance. Fourteen or 15 trabecular bone specimens from the radius were imaged for conducting this in vitro project. The imaging data from one dual-energy X-ray absorptiometry (DXA), two multi-slice computed tomography (MSCT), one high-resolution peripheral quantitative computed tomography (HR-pQCT) and four CBCT devices were segmented using an in-house developed code based on homogeneity thresholding. Seven trabecular microarchitecture parameters, as well as two trabecular bone stiffness parameters, were computed from the segmented data. Measurements from micro-computed tomography (micro-CT) data of the same bone specimens were regarded as gold standard. Correlations between MSCT and micro-CT data showed great variations, depending on device, imaging parameters and between the bone parameters. Only the bone-volume fraction (BV/TV) parameter was stable with strong correlations. Regarding both HR-pQCT and CBCT, the correlations to micro-CT were strong for bone structure parameters as well as bone stiffness parameters. The CBCT device 3D Accuitomo showed the strongest correlations, but overestimated BV/TV more than three times compared to micro-CT. The imaging protocol most often used in clinical imaging practice at our clinic demonstrated strong correlations as well as low radiation dose. CBCT data of trabecular bone can be used for analysing trabecular bone properties, like bone microstructure and bone biomechanics, showing strong correlations to the reference method of micro-CT. The results depend on choice of CBCT device as well as segmentation method used. The in-house developed code based on homogeneity thresholding is appropriate for CBCT data. The overestimations of BV/TV must be considered when estimating bone properties in future clinical dental implant and osteoporosis research.
Download or read book Accuracy of Cone beam Computerized Tomography CBCT for the Measurement of Linear Distances in the Mandible an Ex Vivo Study written by Michal Halperin and published by . This book was released on 2011 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Comparative Linear Accuracy of Cone Beam CT Derived 3D Images in Orthodontic Analysis written by April A. Brown and published by . This book was released on 2008 with total page 166 pages. Available in PDF, EPUB and Kindle. Book excerpt: Objective. To compare the in vitro reliability and accuracy of linear measurements between cephalometric landmarks on CBCT 3D images with varying basis projection images to direct measurements on human skulls. Methods. Sixteen linear dimensions between anatomical sites marked on 19 human skulls were directly measured. Skulls were imaged with CBCT at three settings: 153, 306, and 612 basis projections. The mean absolute error and modality mean of linear measurements between landmarks on 3D images were compared to the anatomic truth. Results. No difference in mean absolute error between the scan settings was found. The average skull absolute error between marked reference points were less than the distances between unmarked reference sites. Conclusion. CBCT measurements were consistent between scan sequences and for direct measurements between marked reference points. Reducing the number of projections for 3D reconstruction did not lead to reduced dimensional accuracy and potentially provides reduced patient radiation exposure.
Download or read book Imaging based Numerical Study of Biomechanics and Bone Density Distribution in Human Alveolar Bone written by Kangning Su and published by . This book was released on 2021 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Bone adapts to the changes of mechanical stimulus by bone remodeling activities. Bone remodeling results in the variation of bone density. This study presents the results of numerical simulations of biomechanics and mechanically adaptive bone remodeling in the human alveolar bone. Finite element models were built based on the micro X-ray computed tomography (micro-CT) images or clinical cone-beam computed tomography (CBCT) images. Strain in the alveolar bone under tooth loading or implant loading was calculated. Bone density distribution as a response to the mechanical stimulus was also computed. The results were in good agreement with experimentally measured strain using mechanical testing coupled with micro-CT and with the bone density distribution measured using clinical CBCT images. The models were used to predict the strain field with different implant positions. A number of numerical algorithms have been developed to model the adaptive bone remodeling under mechanical loads for orthopedic and dental applications. The parametric study examines the effects of several model parameters on the computed apparent bone density in mandible under normal chewing and biting forces. The density change rate was based on the strain energy density per unit mass. The algorithms used in this study containing an equilibrium zone (lazy zone) and saturated values of density change rate provided certain stability to result in convergence without discontinuous checkerboard patterns. The parametric study shows that when different boundary conditions were applied, the bone density distributions at convergence were very different, except in the vicinity of the applied loads. Compared with the effects of boundary conditions, the models are less sensitive to the choice of initial density values. Several models starting from different initial density values resulted in similar but not exactly the same bone density distribution at convergence. The results also show that, a higher reference value of mechanical stimulus resulted in lower average bone density at convergence. The width of equilibrium zone did not substantially affect the average density at convergence. However, with increasing width, the areas with the highest and the lowest bone density areas were all reduced. Moreover, the results of mechanically adaptive bone remodeling algorithms were compared with the information extracted from clinical images. Cone-beam computed tomography (CBCT) images of multiple patients were collected and processed to obtain the standard outline of mandible and average bone density distribution on the sagittal cross-sectional at the center of lateral incisors. Finite element models were built to compute the strain and stress in mandible under normal chewing and biting forces. Bone remodeling algorithm was carried out using strain energy density per unit bone mass as the mechanical stimulus to compute the bone density distribution at equilibrium. The computed bone density distribution exhibited close agreement with that obtained from CBCT image analysis with a coefficient of correlation of 0.87. The bite forces applied on teeth were transmitted through the tooth roots to the bone surrounding them, thus stimulated high trabecular bone density (1.6 g/cm3) near the tooth roots. The bending and torsion moments on the sagittal section of mandible resulted in lower bone density near the center (0.5 g/cm3) than those towards the edge of the section. The results add new knowledge of anatomy and biomechanics of mandibles and provide a new method to compare the results of numerical simulations of mechanically adaptive bone remodeling to in vivo data. Also, 3D finite element models were built based on micro-CT images and the results were compared with those obtained from mechanical testing coupled with micro-CT. Bone-implant mechanics is one of the factors that contribute to implant stability and success. In this work, voxel-based finite element models were built based on the micro-CT images of human cadaveric mandible specimens before and after implant placement. The elastic moduli of bone elements were assigned based on the intensity values in the micro-CT images of bone-tooth specimens before implant placement to avoid the beam hardening artifacts and to increase the connectivity and accuracy of the models. The implant positions in the models were determined by the micro-CT images of bone-implant specimens after implant placement. The computed results show that high strain appeared at the bone-implant contact locations and manifested into the supporting bone, including the buccal and lingual bone plates, which were not in direct contact with the implants. The strain concentration in the buccal bone plates was more substantial than that in the lingual bone plate, because the buccal bone plates were thinner than the lingual bone plates. The average values of maximum principal strain in the buccal and lingual regions of interest (ROI) were in good agreement with those experimentally measured using mechanical testing coupled with micro-CT and digital volume correlation. The implant positions were then virtually changed in the models by translating the implant towards the buccal or the lingual direction. The computed strain in the buccal bone decreased when the implant was virtually placed in the models away from the buccal bone plate. The strain in lingual bone also deceased when the implant was virtually moved in the model from the center of the alveolar socket towards the lingual or buccal plate. The results indicate that the distance of implant to the buccal bone plate can affect the mechanical stimuli in bone, especially in the buccal bone plate, which may subsequently affect the bone remodeling process and buccal bone resorption.
Download or read book Cone Beam Computed Tomography in Orthodontics written by Sunil D. Kapila and published by John Wiley & Sons. This book was released on 2014-08-29 with total page 880 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since its introduction to dentistry, cone beam computed tomography (CBCT) has undergone a rapid evolution and considerable integration into orthodontics. However, despite the increasing popularity of CBCT and progress in applying it to clinical orthodontics, the profession has lacked a cohesive, comprehensive and objective reference that provides clinicians with the background needed to utilize this technology optimally for treating their patients. Cone Beam Computed Tomography in Orthodontics provides timely, impartial, and state-of-the-art information on the indications and protocols for CBCT imaging in orthodontics, clinical insights gained from these images, and innovations driven by these insights. As such, it is the most current and authoritative textbook on CBCT in orthodontics. Cone Beam Computed Tomography in Orthodontics is organized to progress sequentially through specific topics so as to build the knowledgebase logically in this important and rapidly evolving field. Part I provides the foundational information on CBCT technology, including radiation exposure and risks, and future evolutions in computed tomography. Part II presents the Principles and Protocols for CBCT Imaging in Orthodontics, focusing on developing evidence-based criteria for CBCT imaging, the medico-legal implications of CBCT to the professional and the protocols and integration of this technology in orthodontic practice. Part III provides critical information on CBCT-based Diagnosis and Treatment Planning that includes how to interpret CBCT scans, identify incidental pathologies and the possible other uses of this technology. Part IV covers practical aspects of CBCT’s Clinical Applications and Treatment Outcomes that encompasses a range of topics, including root morphology and position, treatment of impacted teeth, virtual surgical treatment planning and outcomes, and more.
Download or read book Dental Ultrasound in Periodontology and Implantology written by Hsun-Liang (Albert) Chan and published by Springer Nature. This book was released on 2020-10-29 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents up-to-date information on promising indications for ultrasound in contemporary periodontics and implant therapy with the aim of assisting researchers and dental practitioners to use this novel imaging modality to advance research and patient care. Readers will find clear guidance on the application of ultrasound for evaluation of periodontal and peri-implant tissues. The mechanism of ultrasound imaging is explained in detail and compared to other imaging modalities. Furthermore, the role of ultrasound in the planning and execution of implant surgery and the assessment of implant stability is discussed. The book closes by considering the potential dental applications of functional ultrasound and volumetric ultrasound. This book will potentially be of high values for dental surgeons, periodontists, general dentists, orthodontists, dental hygienists, dental assistants, dental researchers and other practitioners, etc.
