Search results for "Biomedical engineering"
showing 10 items of 2020 documents
Biomechanical analysis of two types of osseointegrated transfemoral prosthesis
2020
In the last two decades, osseointegrated prostheses have been shown to be a good alternative for lower limb amputees experiencing complications in using a traditional socket-type prosthesis
Influence of voxel size on the accuracy of linear measurements of the condyle in images of cone beam computed tomography: A pilot study
2018
Background To analyze the influence of voxel size and exposure time on the accuracy of linear measurements of the condyle. Material and methods Four macerated hemi-mandibles of pigs were scanned in nine different voxel size protocols. Three-dimensional models of the condyle were generated in order to establish a comparison between linear measurements obtained with each voxel protocol and those obtained with a caliper (gold standard). The comparison between the protocols was performed considering the average of the two measurements of the condyle in the latero-medial (LM) and antero-posterior (AP) axes and also through repeated measurement ANOVA with rank transformation. The level of signifi…
Accuracy and Reliability of Cone-Beam Computed Tomography for Linear and Volumetric Mandibular Condyle Measurements. A Human Cadaver Study
2017
AbstractThe accuracy of Cone-Beam Computed Tomography (CBCT) on linear and volumetric measurements on condyles has only been assessed on dry skulls. The aim of this study was to evaluate the reliability and accuracy of linear and volumetric measurements of mandibular condyles in the presence of soft tissues using CBCT. Six embalmed cadaver heads were used. CBCT scans were taken, followed by the extraction of the condyles. The water displacement technique was used to calculate the volumes of the condyles and three linear measurements were made using a digital caliper, these measurements serving as the gold standard. Surface models of the condyles were obtained using a 3D scanner, and superim…
Influence of enhancement filters in apical bone loss measurement: A cone-beam computed tomography study
2016
Background The use of cone-beam computed tomography images (CBCT) providing a better assessment of bone injuries, although the sensibility of lesions measurement might be improved by the use of enhancement filters. Objective: This study aimed to analyze the influence of enhancement filters in apical bone loss measurement. Material and Methods Eighteen CBCT cases randomly selected of apical bone loss were evaluated. The analyses were carried out following the evaluation in axial, coronal and sagittal protocols, using enhancement filters as Hard, Normal, and Very Sharp. The variables were statistically analyzed by Friedman and Wilcoxon test, Spearman’s rho, and intraclass correlation coeffici…
Prosthetically‐Driven Full‐Mouth Implant‐Supported Prostheses Using Guided Surgical Implant Planning with Composite Resin Markers: A Case Report
2021
This report describes a prosthetically-driven implant planning method, guided by the alignment procedures between the cone beam computed tomography, intraoral digital scans, and digitized maxillary and mandibular interim complete dentures using intraoral composite resin markers as a common reference. The markers were attached to the keratinized oral mucosa of the edentulous ridges using cyanoacrylate and kept in place during the digitizing procedures. The technique provides a simpler and more economical alternative to conventional prosthetically-driven static implant planning methods.
Focal adhesions and assessment of cytotoxicity
1999
Focal adhesions are highly ordered assemblies of transmembrane receptors, extracellular matrix proteins, and a large number of cytoplasmic proteins, including structural proteins, as well as tyrosine kinases, phosphatases, and their substrates. They are now accepted as a prime component of signal transduction. Because focal adhesions also play an important role in cell morphology and migration, it can be argued that their presence is indicative of healthy cells. This has been the reason for several research groups to conclude that biomaterials sustaining focal adhesion assembly are biocompatible. In this study we demonstrate that cells under cytotoxic stress may still be able to retain thei…
Examination Technique of Confocal Laser Endomicroscopy
2007
The first publication about a confocal fluorescence microscope integrated into the distal tip of a conventional colonoscope (Pentax EC 3830FK, Tokyo, Japan) appeared in 2004 [1], showing that in vivo microscopy at subcellular resolution (0.7 µm) simultaneously displayed with white-light endoscopy had become possible. Today, endomicroscopy can be performed in the upper and lower GI tract [2]–[10]. This chapter deals with the examination technique of confocal laser endomicroscopy.
Advances in confocal laser endomicroscopy for the diagnosis of gastrointestinal diseases
2009
Confocal laser endomicroscopy (CLE) is a novel technique enabling in vivo microscopy of the human gastrointestinal mucosa. Cellular details even below the tissue surface can be visualized at high resolution during ongoing endoscopy.This review summarizes the current clinical data on the use of CLE in different disease states and discusses a perspective for future clinical and scientific application of CLE.Review on published literature and meeting abstracts.Confocal laser endomicroscopy covers a growing field of indications in both upper and lower gastrointestinal endoscopy and beyond. It has been shown to reliably predict the presence of neoplastic lesions and inflammatory changes of the g…
A method for measuring mitochondrial mass and activity
2007
Mitochondria, responsible for the energy-generating process essential for the cell metabolism, differ for the number, localization and activity in animal cells and tissues in relation to the energetic needs. Using fluorescent probes specific for mitochondria, Mitotracker Green (MTG) and Orange (MTO), and Confocal Laser-Scanning Microscope (CLSM), we elaborated a method to measure in vivo the mitochondrial mass and activity, in sea urchin Paracentrotus lividus eggs and embryos. The analysis of captured images, revealed a variation of mitochondrial distribution and an increase of activity after fertilization.
Argumentation graphs with constraint-based reasoning for collaborative expertise
2018
International audience; Collaborative processes are very important in telemedicine domain since they allow for making right decisions in complex situations with multidisciplinary staff. When modelling these collaborative processes, some inconsistencies can appear. In semantic modelling (conceptual graphs), these inconsistencies are verified using constraints. In this work, collaborative processes are represented using an argumentation system modelled in a conceptual graph formalism where inconsistencies could be particular bad attack relation between arguments. To overcome these inconsistencies, two solutions are proposed. The first one is to weight the arguments evolving in the argumentati…