Aim: To assess the three dimensional (3D) surface accuracy of a phantom's face acquired from a cone-beam computed tomography (CBCT) scan and to determine the reliability of selected cephalometric measurements performed with Maxilim software (Medicim N.V., Mechelen, Belgium).
Material And Methods: A mannequin head was imaged with a CBCT (I-CAT, Imaging Sciences International, Inc., Hatfield, USA). The data were used to produce 3D surface meshes (Maxilim and Mimics, Materialise N.V., Leuven, Belgium) which were compared with an optical surface scan of the head using Focus Inspection software (Metris N.V., Leuven, Belgium). The intra- and inter-observer reliability for the measurement of distances between facial landmarks with Maxilim 3D cephalometry were determined by calculating Pearson correlation coefficients and intraclass correlation (ICC). The Dahlberg formula was used to assess the method error (ME).
Results: (1) The maximal range of the 3D mesh deviations was 1.9 mm for Maxilim, and 1.8mm for Mimics segmentation. (2) Test-retest and inter-observer reliability were high; Pearson's correlation coefficient was 1.000 and the ICC was 0.9998. The ME of the vertical measurements was a little larger than that calculated for the width measurements. Maximum ME was 1.33 mm.
Conclusions: The 3D surface accuracy of CBCT scans segmented with Maxilim and Mimics software is high. Maxilim also shows satisfactory intra- and inter-assessor reliability for measurement of distances on a rigid facial surface.
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http://dx.doi.org/10.1016/j.jcms.2008.07.006 | DOI Listing |
J Periodontol
January 2025
Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, Zhejiang Provincial Clinical Research Center for Oral Diseases, Key Laboratory of Oral Biomedical Research of Zhejiang Province, Cancer Center of Zhejiang University, Hangzhou, China.
Background: The clinical evidence about alveolar ridge changes following molar extraction and how the alveolar bone morphology influences the ridge dimensional changes remains limited.
Methods: A total of 192 patients with 199 molar extractions were included in this retrospective study. Cone-beam computed tomography (CBCT) images of patients were obtained 0-3 months pre extraction and 6-12 months post extraction.
In image-guided radiotherapy (IGRT), four-dimensional cone-beam computed tomography (4D-CBCT) is critical for assessing tumor motion during a patients breathing cycle prior to beam delivery. However, generating 4D-CBCT images with sufficient quality requires significantly more projection images than a standard 3D-CBCT scan, leading to extended scanning times and increased imaging dose to the patient. To address these limitations, there is a strong demand for methods capable of reconstructing high-quality 4D-CBCT images from a 1-minute 3D-CBCT acquisition.
View Article and Find Full Text PDFWorld J Clin Cases
January 2025
Stomatological Hospital and College, Anhui Medical University, Hefei 230032, Anhui Province, China.
Background: Complicated crown-root fracture (CRF) involves severe injury to the crown, root, and pulp, and may be accompanied by multiple root fractures. The loss of a tooth has lifelong consequences for children and teenagers, but the maintenance of pulp health and the calcific healing of multiple root fractures are rarely reported in the literature.
Case Summary: This case reports healing of a permanent tooth with complicated crown-root and additional root fractures, in which pulp health was maintained.
Med Phys
January 2025
Department of Radiology, University of Wisconsin-Madison, Madison, Wisconsin, USA.
Background: Histotripsy is a non-invasive, non-ionizing, non-thermal focused ultrasound technique. High amplitude short acoustic pulses converge to create high negative pressures that cavitate endogenous gas into a bubble cloud leading to mechanical tissue destruction. In the United States, histotripsy is approved to treat liver tumors under diagnostic ultrasound guidance but in initial clinical cases, some areas of the liver have not been treated due to bone or gas obstructing the acoustic window for targeting.
View Article and Find Full Text PDFBDJ Open
January 2025
Department of Oral and Maxillofacial Surgery (Head: Prof. Dr. Dr. Bernd Lethaus), University Hospital Tübingen, Eberhard Karls Universität Tübingen, Osianderstr. 2-8, D-72076, Tübingen, Germany.
Objectives: The aim of the present study was to compare the accuracy of fully guided implant insertion in vitro achieved by two fabrication methods in a cohort of undergraduates. We hypothesized that both methods achieve a comparable accuracy.
Methods: Surface scans and cone beam computed tomography images of 48 mandibular models were matched.
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