234 research outputs found
Three-dimensional regional displacement after surgical-orthodontic correction of Class III malocclusion
To investigate how displacements of maxillo-mandibular structures are associated with each other at splint removal and one year post-surgery following 1-jaw and 2-jaw surgeries for correction of Class III malocclusion
Zygomaticomaxillary suture maturation: Part II-The influence of sutural maturation on the response to maxillary protraction
To evaluate the influence of the maturational stages of zygomaticomaxillary sutures (ZMS) on the response to maxillary protraction
Metallic Brackets Bonded with Resin-reinforced Glass Ionomer Cements under Different Enamel Conditions Matheus Melo Pithon a ; Rogé rio Lacerda dos Santos a ; Má rlio Vinícius de Oliveira
ABSTRACT Objective: To assess the shear bond strength of metallic orthodontic brackets bonded with either Fuji Ortho or Ortho Glass LC resin-reinforced glass ionomer cements to enamel surfaces under different conditions, namely, enamel without etching, enamel conditioned with 37% phosphoric acid and enamel conditioned with Transbond Plus Self Etching Primer (TPSEP). Materials and Methods: One hundred and five bovine inferior incisors were divided into seven groups (n ϭ 15). In group 1 (control) Transbond XT was used according to the manufacturer's recommendations. In groups 2, 3, and 4 all using Fuji Ortho LC, the brackets were bonded, respectively, to enamel nonetched, enamel etched with 37% phosphoric acid, and enamel etched with TPSEP. In groups 5, 6, and 7, the bonding was performed using Ortho Glass LC under the same enamel conditions observed in the other experimental groups. After 24 hours, shear bond strength tests were performed for all samples at a crosshead speed of 0.5 mm/min
Federating heterogeneous datasets to enhance data sharing and experiment reproducibility
Recent studies have demonstrated the difficulties to replicate scientific findings and/or experiments published in past.1 The effects seen in the replicated experiments were smaller than previously reported. Some of the explanations for these findings include the complexity of the experimental design and the pressure on researches to report positive findings. The International Committee of Medical Journal Editors (ICMJE) suggests that every study considered for publication must submit a plan to share the de-identified patient data no later than 6 months after publication. There is a growing demand to enhance the management of clinical data, facilitate data sharing across institutions and also to keep track of the data from previous experiments. The ultimate goal is to assure the reproducibility of experiments in the future. This paper describes Shiny-tooth, a web based application created to improve clinical data acquisition during the clinical trial; data federation of such data as well as morphological data derived from medical images; Currently, this application is being used to store clinical data from an osteoarthritis (OA) study. This work is submitted to the SPIE Biomedical Applications in Molecular, Structural, and Functional Imaging conference
Novel application and validation of in vivo micro‐CT to study bone modelling in 3D
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/149362/1/ocr12265.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/149362/2/ocr12265_am.pd
Incorporating 3-dimensional models in online articles
Introduction The aims of this article are to introduce the capability to view and interact with 3-dimensional (3D) surface models in online publications, and to describe how to prepare surface models for such online 3D visualizations. Methods Three-dimensional image analysis methods include image acquisition, construction of surface models, registration in a common coordinate system, visualization of overlays, and quantification of changes. Cone-beam computed tomography scans were acquired as volumetric images that can be visualized as 3D projected images or used to construct polygonal meshes or surfaces of specific anatomic structures of interest. The anatomic structures of interest in the scans can be labeled with color (3D volumetric label maps), and then the scans are registered in a common coordinate system using a target region as the reference. The registered 3D volumetric label maps can be saved in.obj,.ply,.stl, or.vtk file formats and used for overlays, quantification of differences in each of the 3 planes of space, or color-coded graphic displays of 3D surface distances. Results All registered 3D surface models in this study were saved in.vtk file format and loaded in the Elsevier 3D viewer. In this study, we describe possible ways to visualize the surface models constructed from cone-beam computed tomography images using 2D and 3D figures. The 3D surface models are available in the article's online version for viewing and downloading using the reader's software of choice. These 3D graphic displays are represented in the print version as 2D snapshots. Overlays and color-coded distance maps can be displayed using the reader's software of choice, allowing graphic assessment of the location and direction of changes or morphologic differences relative to the structure of reference. The interpretation of 3D overlays and quantitative color-coded maps requires basic knowledge of 3D image analysis. Conclusions When submitting manuscripts, authors can now upload 3D models that will allow readers to interact with or download them. Such interaction with 3D models in online articles now will give readers and authors better understanding and visualization of the results
Evaluation of the shear bond strength of the Orthobond composite under different conditions
Objective: Evaluate the shear bond strength of metal brackets bonded with Orthobond composite (Dental Morelli Ltda, Sorocaba, Brazil) under different enamel surface conditions. Methods: Ninety bovine mandibular permanent incisors were divided into six groups (n = 15). In Group 1 (control) and Group 2 the bonding procedures were performed by using Transbond XT (3M Unitek, Monrovia, USA) and Orthobond (Dental Morelli Ltda, Sorocaba, Brazil) composites,respectively, according to the manufacturer’s recommendations. In the other groups brackets were bonded with Orthobond composite (Dental Morelli Ltda, Sorocaba, Brazil) as follows: Group 3 – dental surface conditioned with Transbond Plus Self-Etching Primer (3M Unitek, Monrovia, USA); Group 4 – bonding procedure without application of Orthoprimer (Dental Morelli Ltda, Sorocaba, Brazil); Group 5 - Eagle Bond applied on saliva/blood-contaminated dental surface; and Group 6 – use of homogenized Orthobond (Dental Morelli Ltda, Sorocaba, Brazil). After bonding the brackets, all the samples were submitted to shear bond strength tests by means of an Emic Universal Testing Machine at a crosshead speed of 0.5 mm/min. The results obtained in mega Pascal (MPa) were submitted to the analysis of variance (ANOVA) and then to the Tukey test. Results: The results in mega Pascal showed statistically significant differences between Groups 1 and 2 (p= 0.041), 1 and 5 (p=0.000) and between 4 and 5 (p=0.016). The ARI (Adhesive Remnant Index) scores showed evidence of a higher number of fractures at the bracket/composite interface. Conclusion: In all tested situations the Orthobond (Dental Morelli Ltda, Sorocaba, Brazil) was shown to be apt for bracket bonding
SVA: Shape variation analyzer
Temporo-mandibular osteo arthritis (TMJ OA) is characterized by progressive cartilage degradation and subchondral bone remodeling. The causes of this pathology remain unclear. Current research efforts are concentrated in finding new biomarkers that will help us understand disease progression and ultimately improve the treatment of the disease. In this work, we present Shape Variation Analyzer (SVA), the goal is to develop a noninvasive technique to provide information about shape changes in TMJ OA. SVA uses neural networks to classify morphological variations of 3D models of the mandibular condyle. The shape features used for training include normal vectors, curvature and distances to average models of the condyles. The selected features are purely geometric and are shown to favor the classification task into 6 groups generated by consensus between two clinician experts. With this new approach, we were able to accurately classify 3D models of condyles. In this paper, we present the methods used and the results obtained with this new tool
Shear bond strength of orthodontic brackets to enamel under different surface treatment conditions
The purpose of the present study was to evaluate the shear bond strength to enamel and the adhesive remnant index (ARI) of both metallic and polycarbonate brackets bonded under different conditions. Ninety bovine permanent mandibular incisors were embedded in acrylic resin using PVC rings as molds and assigned to 6 groups (n=15). In Groups 1 (control) and 3, metallic and polycarbonate orthodontic brackets were, respectively, bonded to the enamel surfaces using Transbond XT composite according to the manufacturer's recommendations. In Groups 2 and 4, both types of brackets were bonded to enamel with Transbond XT composite, but XT primer was replaced by the OrthoPrimer agent. In Groups 5 and 6, the polycarbonate bracket bases were sandblasted with 50-mm aluminum-oxide particle stream and bonded to the enamel surfaces prepared under the same conditions described in Groups 3 and 4, respectively. After bonding, the specimens were stored in distilled water at 37ºC for 24 hours and then submitted to shear bond strength test at a crosshead speed of 0.5 mm/min. The results (MPa) showed no statistically significant difference between Groups 4 and 6 (p>;0.05). Likewise, no statistically significant differences (p>;0.05) were found among Groups 1, 2, and 5, although their results were significantly lower than those of Groups 4 and 6 (
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