Wear Distribution Detection of Knee Joint Prostheses by Means of 3D Optical Scanners

Abstract

The objective of this study was to examine total knee polyethylene inserts from in vitro simulation to evaluate and display—using a 3D optical scanner—wear patterns and wear rates of inserts exposed to wear by means of simulators. Various sets of tibial inserts have been reconstructed by using optical scanners. With this in mind, the wear behavior of fixed and mobile bearing polyethylene knee configurations was investigated using a knee wear joint simulator. After the completion of the wear test, the polyethylene menisci were analyzed by an innovative 3D optical scanners in order to evaluate the 3D wear distribution on the prosthesis surface. This study implemented a new procedure for evaluating polyethylene bearings of joint prostheses obtained after in vitro wear tests and the proposed new approach allowed quantification of the contact zone on the geometry of total knee prostheses. The results of the present study showed that mobile TKPs (total knee prosthesis) have lower wear resistance with respect to fixed TKPs.

3d Modelling of the Mamari Tablet From the Rongorongo Corpus: Acquisition, Processing Issues, and Outcomes

“…For this reason, the 3D modelling was carried out with the Scan-Rider 1.2 laser scanner manufactured by VGER, based on Structured Light technology. ScanRider 1.2 was chosen due to its high performances in terms of nominal precision, accuracy and resolution required to reconstruct the smallest details or high frequencies of the object, such as the inscriptions themselves (Lastilla et al, 2019;Affatato et al, 2017).…”

Advances in Optomechatronics: An Automated Tilt-Rotational 3D Scanner for High-Quality Reconstructions

“…This model was not measured and calibrated with a reference measuring machine and was just used to assess precision, repeatability, and reproducibility in small volumes. The first experimental campaign was performed in a volume comprised between 133 × 100 × 100 mm 3 and 300 × 225 × 225 mm 3 . According to Reference [32] (Part 3), the artifact with the three test spheres was moved in fifteen different arbitrary positions, by means of the tilt-rotational mechanical positioning system.…”

“…The second experimental campaign was performed in a volume comprised between 66 × 50 × 50 mm 3 and 133 × 100 × 100 mm 3 . According to the definitions in References [30,31], the parameters assessed with this experimentation were the repeatability and the reproducibility, based on the mean values on the 3D evaluations.…”

“…For instance, reverse engineering [1,2] and the development of industrial design or medical components [3][4][5], surface analysis [6,7], wear assessment [3,[8][9][10][11][12], deformation analysis and quality control [3,13], robot positioning, and guiding systems [14][15][16] are typical industrial and medical applications where 3D digital reconstructions are crucial. Three-dimensional scanners are based on various working principles and technologies with different advantages, limitations, and costs.…”

New Instrumented Trolleys and A Procedure for Automatic 3D Optical Inspection of Railways

“…For these reasons, the development of robotic or automated trolleys based on the use of 3D optical measuring instruments can be considered essential for diagnostics and the inspection of rail tracks, because they can provide data to get a complete scenario for the damage and they would allow the performance of inspection procedures with minimal human interventions, both during the measurement and data processing phases. In fact, 3D optical digitizers are becoming more and more useful to perform inspection and quality control in mechanics and biomechanics, thanks to their advanced performance due to technological innovations [2][3][4][5][6][7][8][9]. In [2], a cutting-edge procedure to assess wear, based on 3D optical digitizers, was presented and discussed.…”