This study presents a method for measuring the low volumetric wear expected in ceramic total disc replacements, which can be used to replace intervertebral discs in the spine, using non-contacting optical methods. Alumina-on-alumina ball-on-disc tests were conducted with test conditions approximating those of cervical (neck region of the spine) total disc replacement wear tests. The samples were then scanned using a three-dimensional non-contacting optical profilometer and the data used to measure surface roughness and develop a method for measuring the wear volume. The results showed that the magnification of the optical lens affected the accuracy of both the surface roughness and wear volume measurements. The method was able to successfully measure wear volumes of 0.0001 mm(3), which corresponds to a mass of 0.0001 mg, which would have been undetectable using the gravimetric method. A further advantage of this method is that with one scan the user can measure changes in surface topography, volumetric wear and the location of the wear on the implant surface. This method could also be applied to more severe wear, other types of orthopaedic implants and different materials.
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http://dx.doi.org/10.1177/0954411915577119 | DOI Listing |
Polymers (Basel)
September 2022
The Key Laboratory of Bionic Engineering (Ministry of Education), The College of Biological and Agricultural Engineering, Jilin University, 5988 Renmin Street, Changchun 130025, China.
Shape-memory polymers (SMPs) have gradually emerged in the mechanism and biomedical fields and facilitate the upgrading of industrial mechanisms and the breakthrough of technical bottlenecks. However, most of the SMPs are infeasible in harsh environments, such as aerospace, due to the low glass transition temperature. There are still some works that remain in creating truly portable or non-contacting actuators that can match the performances and functions of traditional metal structures.
View Article and Find Full Text PDFSensors (Basel)
June 2022
Faculty of Science and Engineering, Waseda University, Tokyo 1690051, Japan.
To give people more specific information on the quality of their daily motion, it is necessary to continuously measure muscular activity during everyday occupations in an easy way. The traditional methods to measure muscle activity using a combination of surface electromyography (sEMG) sensors and optical motion capture system are expensive and not suitable for non-technical users and unstructured environment. For this reason, in our group we are researching methods to estimate leg muscle activity using non-contact wearable sensors, improving ease of movement and system usability.
View Article and Find Full Text PDFDent Mater
April 2021
King's College London, Faculty of Dentistry, Oral and Craniofacial Sciences, Guy's Hospital, Tower Wing, London, SE1 9RT, UK. Electronic address:
Objective: To investigate the measurement threshold of an intra-oral scanner (IOS) on polished human enamel.
Methods: The optical performance of an IOS was compared to a gold-standard non contacting laser profilometer (NCLP), on a painted microscope slide, compared to increasing particle size of silicon-carbide papers (21.8-269.
Methods Mol Biol
March 2021
Kosair Charities Pediatric Heart Research Program, Cardiovascular Innovation Institute, University of Louisville, Louisville, KY, USA.
The delivery of cells into damaged myocardium induces limited cardiac regeneration due to extensive cell death. In an effort to limit cell death, our lab formulates three-dimensional matrices as a delivery system for cell therapy. Our primary work has been focused on the formation of engineered cardiac tissues (ECTs) from human-induced pluripotent stem cell-derived engineered cardiac cells.
View Article and Find Full Text PDFPLoS One
April 2020
Photono Oy, Helsinki, Finland.
People suffering from glaucoma often endure high intra-ocular pressure (IOP). Methods for determining IOP either contact the eye or are unpleasant to some patients. There is therefore a need for a rapid and patient friendly non-contacting method to determine IOP.
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