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3D surface scanning

Sen Wang, Xinxin Zuo, Chao Du, Runxiao Wang, Jiangbin Zheng, Ruigang Yang
This paper deals with the 3D reconstruction problem for dynamic non-rigid objects with a single RGB-D sensor. It is a challenging task as we consider the almost inevitable accumulation error issue in some previous sequential fusion methods and also the possible failure of surface tracking in a long sequence. Therefore, we propose a global non-rigid registration framework and tackle the drifting problem via an explicit loop closure. Our novel scheme starts with a fusion step to get multiple partial scans from the input sequence, followed by a pairwise non-rigid registration and loop detection step to obtain correspondences between neighboring partial pieces and those pieces that form a loop...
March 16, 2018: Sensors
Qiang Chen, Sijie Niu, Wangyi Fang, Yuanlu Shuai, Wen Fan, Songtao Yuan, Qinghuai Liu
BACKGROUND AND OBJECTIVE: The measurement of choroidal volume is more related with eye diseases than choroidal thickness, because the choroidal volume can reflect the diseases comprehensively. The purpose is to automatically segment choroid for three-dimensional (3D) spectral domain optical coherence tomography (SD-OCT) images. METHODS: We present a novel choroid segmentation strategy for SD-OCT images by incorporating the enhanced depth imaging OCT (EDI-OCT) images...
May 2018: Computer Methods and Programs in Biomedicine
Bruno Sommacal, Miodrag Savic, Andreas Filippi, Sebastian Kühl, Florian M Thieringer
PURPOSE: To compare the suitability of a fused filament fabrication (FFF) consumer 3D printer with a professional digital light processing (DLP) printer for the production of surgical templates for guided oral implant surgery. MATERIALS AND METHODS: Eight virtual templates were printed with two different 3D printers. These were optically scanned and the incongruences between virtual and printed templates were determined after alignment of the surface scans and the virtual data...
March 15, 2018: International Journal of Oral & Maxillofacial Implants
V A Shaimova, T B Shaimov, R B Shaimov, A Yu Galin, Zh A Goloshchapova, P K Ryzhkov, A V Fomin
PURPOSE: To develop methods for evaluating effectiveness of YAG-laser vitreolysis of vitreous floaters. MATERIAL AND METHODS: The study included 144 patients (173 eyes) who had underwent YAG-laser vitreolysis and were under observation from 01.09.16 to 31.01.18. The patients were 34 to 86 years old (mean age 62.7±10.2 years), 28 (19.4%) patients were male, 116 (80.6%) - female. All patients underwent standard and additional examination: ultrasonography (Accutome B-scan plus, U...
2018: Vestnik Oftalmologii
Wen Shuo Chen, Ling Yu Guo, Chia Chun Tang, Cheng Kang Tsai, Hui Hua Huang, Ting Yu Chin, Mong-Lin Yang, Yui Whei Chen-Yang
In this study, we first synthesized a slow-degrading silica nanofiber (SNF2) through an electrospun solution with an optimized tetraethyl orthosilicate (TEOS) to polyvinyl pyrrolidone (PVP) ratio. Then, laminin-modified SNF2, namely SNF2-AP-S-L, was obtained through a series of chemical reactions to attach the extracellular matrix protein, laminin, to its surface. The SNF2-AP-S-L substrate was characterized by a combination of scanning electron microscopy (SEM), Fourier transform-infrared (FTIR) spectroscopy, nitrogen adsorption/desorption isotherms, and contact angle measurements...
March 14, 2018: Nanomaterials
David Anssari Moin, Bassam Hassan, Daniel Wismeijer
PURPOSE: To evaluate the feasibility of a commercially available immediate root analog implant system Replicate (Natural Dental Implants). MATERIALS AND METHODS: Five consecutive patients in need of an implant in the premolar region were recruited for this pilot study. Following clinical examination, a cone beam computed tomography scan was made and the dental impressions digitized. On the basis of the superimposition of these datasets, a three-dimensional (3D) envelope was created for the selected tooth...
March 2018: International Journal of Oral & Maxillofacial Implants
Carolyn Kincade, Lindsay McHutchion, Johan Wolfaardt
The present report describes the digital design of patient-specific milled abutments for the retention of osseointegrated facial prostheses by using digital technology. Patient imaging including surface scans of the patient's head, scans of the patient's definitive cast, and digitally designed prosthesis prototypes were combined to create a digital simulation of the patient. Using this simulation, patient-specific abutments were digitally designed, printed in 3-dimensions (3D), and finally copy-milled in titanium...
March 8, 2018: Journal of Prosthetic Dentistry
Simon J Woodings, J J Bluemink, J H Wilfred de Vries, Yury Niatsetski, Bob van Veelen, Joost Schillings, Jan G M Kok, Jochem W H Wolthaus, Sara L Hackett, Bram van Asselen, Helena Maria van Zijp, Stefan Pencea, David A Roberts, Jan J W Lagendijk, Bas W Raaymakers
As a prerequisite for clinical treatments it was necessary to characterize the Elekta 1.5 T MRI-linac 7 MV FFF radiation beam. Following acceptance testing, beam characterization data were acquired with Semiflex 3D (PTW 31021), microDiamond (PTW 60019), and Farmer-type (PTW 30013 and IBA FC65-G) detectors in an Elekta 3D scanning water phantom and a PTW 1D water phantom. EBT3 Gafchromic film and ion chamber measurements in a buildup cap were also used. Special consideration was given to scan offsets, detector effective points of measurement and avoiding air gaps...
March 9, 2018: Physics in Medicine and Biology
Arianna Cerquiglini, Johann Henckel, Harry Hothi, Niccoló Rotigliano, Michael T Hirschmann, Alister J Hart
PURPOSE: The purpose of the present study was to correlate highly accurate CT measurements of pre-revision total knee arthroplasty (TKA) implant position with findings of retrieval analysis post-revision, to understand the clinical relevance of TKA orientation. METHODS: This study involved 53 retrieved TKA implants with pre-revision 3D-CT scans used to determine coronal (varus-valgus), sagittal (tibial slope) and rotational (internal rotation-external rotation) TKA orientation as well as tibiofemoral leg axis...
March 8, 2018: Knee Surgery, Sports Traumatology, Arthroscopy: Official Journal of the ESSKA
Junaid Malik, Jose Rodriguez, Michael Weisbloom, Haralampos Petridis
PURPOSE: To compare the accuracy (ie, precision and trueness) of full-arch impressions fabricated using either a conventional polyvinyl siloxane (PVS) material or one of two intraoral optical scanners. MATERIALS AND METHODS: Full-arch impressions of a reference model were obtained using addition silicone impression material (Aquasil Ultra; Dentsply Caulk) and two optical scanners (Trios, 3Shape, and CEREC Omnicam, Sirona). Surface matching software (Geomagic Control, 3D Systems) was used to superimpose the scans within groups to determine the mean deviations in precision and trueness (μm) between the scans, which were calculated for each group and compared statistically using one-way analysis of variance with post hoc Bonferroni (trueness) and Games-Howell (precision) tests (IBM SPSS ver 24, IBM UK)...
March 2018: International Journal of Prosthodontics
Xiaoling Yu, Xiaosheng Cheng, Ning Dai, Hu Chen, Changjiang Yu, Yuchun Sun
BACKGROUND AND OBJECTIVE: In dentistry, the complete denture is a conventional treatment for edentulous patients. The computer-aided design and computer-aided manufacturing (CAD/CAM) has been applied on the digital complete denture which is developed rapidly. Tooth selection and arrangement is one of the most important parts in digital complete denture. In this paper, we propose a new method of personalized teeth arrangement. METHODS: This paper presents a method of arranging teeth virtually for a complete denture...
March 2018: Computer Methods and Programs in Biomedicine
Fang Hui, Jinyu Zhu, Pengcheng Hu, Lei Meng, Binglin Zhu, Yan Guo, Baoguo Li, Yuntao Ma
Background and Aims: Global agriculture is facing the challenge of a phenotyping bottleneck due to large-scale screening/breeding experiments with improved breeds. Phenotypic analysis with high-throughput, high-accuracy and low-cost technologies has therefore become urgent. Recent advances in image-based 3D reconstruction offer the opportunity of high-throughput phenotyping. The main aim of this study was to quantify and evaluate the canopy structure of plant populations in two and three dimensions based on the multi-view stereo (MVS) approach, and to monitor plant growth and development from seedling stage to fruiting stage...
March 2, 2018: Annals of Botany
Wenlong Gao, Biao Yang, Ben Tremain, Hongchao Liu, Qinghua Guo, Lingbo Xia, Alastair P Hibbins, Shuang Zhang
Nodal line semimetals (NLS) are three-dimensional (3D) crystals that support band crossings in the form of one-dimensional rings in the Brillouin zone. In the presence of spin-orbit coupling or lowered crystal symmetry, NLS may transform into Dirac semimetals, Weyl semimetals, or 3D topological insulators. In the photonics context, despite the realization of topological phases, such as Chern insulators, topological insulators, Weyl, and Dirac degeneracies, no experimental demonstration of photonic nodal lines (NLs) has been reported so far...
March 5, 2018: Nature Communications
Neslihan Tekçe, Sinan Fidan, Safa Tuncer, Dilan Kara, Mustafa Demirci
PURPOSE: To investigate the effect of accelerated aging on surface properties of glazed CAD/CAM resin blocks using a 2D surface profilometer and a 3D non-contact optical profilometer. MATERIALS AND METHODS: Three types of CAD/CAM resin restorative materials, LAVA Ultimate (3M ESPE, St Paul, MN, USA), VITA Enamic (Vita Zahnfabrik H. Rauter, Bad Säckingen, Germany), and Cerasmart (GC Corparation, Tokyo, Japan) were used for this study. CAD/CAM blocks were cut in 3-mm thickness slabs and divided into three groups; Group 1: control group (specimens polished with 600 grit SCI paper); Group 2: specimens sandblasted, silanized, and glazed with Optiglaze Color (GC); Group 3: glazed specimens subjected to 5000 thermocycles (n=15)...
February 2018: Journal of Advanced Prosthodontics
Salvatore Virga, Rüdiger Göbl, Maximilian Baust, Nassir Navab, Christoph Hennersperger
PURPOSE: Ultrasound acquisitions are typically affected by deformations due to the pressure applied onto the contact surface. While a certain amount of pressure is necessary to ensure good acoustic coupling and visibility of the anatomy under examination, the caused deformations hinder accurate localization and geometric analysis of anatomical structures. These complications have even greater impact in case of 3D ultrasound scans as they limit the correct reconstruction of acquired volumes...
March 2, 2018: International Journal of Computer Assisted Radiology and Surgery
Richarj Mondal, Yuta Saito, Yuki Aihara, Paul Fons, Alexander V Kolobov, Junji Tominaga, Shuichi Murakami, Muneaki Hase
Topological insulators (TIs) are characterized by possessing metallic (gapless) surface states and a finite band-gap state in the bulk. As the thickness of a TI layer decreases down to a few nanometers, hybridization between the top and bottom surfaces takes place due to quantum tunneling, consequently at a critical thickness a crossover from a 3D-TI to a 2D insulator occurs. Although such a crossover is generally accessible by scanning tunneling microscopy, or by angle-resolved photoemission spectroscopy, such measurements require clean surfaces...
March 2, 2018: Scientific Reports
Ehsan Soodmand, Daniel Kluess, Patrick A Varady, Robert Cichon, Michael Schwarze, Dominic Gehweiler, Frank Niemeyer, Dieter Pahr, Matthias Woiczinski
BACKGROUND: The present study contrasts the accuracy of different reconstructed models with distinctive segmentation methods performed by various experts. Seven research groups reconstructed nine 3D models of one human femur based on an acquired CT image using their own computational methods. As a reference model for accuracy assessment, a 3D surface scan of the human femur was created using an optical measuring system. Prior to comparison, the femur was divided into four areas; "neck and greater trochanter", "proximal metaphysis", "diaphysis", and "distal metaphysis"...
March 2, 2018: Biomedical Engineering Online
M X Cheng, T Jiang, Y C Sun, H Y Zhang
OBJECTIVE: To make more accurate occlusal quantitative analysis of three-dimensional (3D) virtual dental models and to compare the occlusal contact obtained by intraoral and dental cast scan. METHODS: In this study, 5 subjects were intraoral scanned using laser scanner (3 shapes, Germany) to obtain the 3D virtual models of one tooth (the first molar), two teeth (the second premolar and the first molar), three teeth (the premolars and the first molar) and their opposite teeth, respectively...
February 18, 2018: Beijing da Xue Xue Bao. Yi Xue Ban, Journal of Peking University. Health Sciences
H Y Zhang, T Jiang, M X Cheng, Y W Zhang
OBJECTIVE: To evaluate the wear intensity and surface roughness of occlusal veneers on premolars made of microhybrid composite resin or two kinds of ceramics in vitro after the thermocycling and cyclic mechanical loading tests. METHODS: In the study,24 fresh extracted human premolars without root canal treatment were prepared (cusps reduction of 1.5 mm in thickness to simulate middle to severe tooth wear, the inclinations of cusps were 20°). The prepared teeth were restored with occlusal veneers made of three different materials: microhybrid composite, heat-pressed lithium disilicate ceramic and computer-aided design/computer-aided manufacturing (CAD/CAM) lithium disilicate ceramic in the thickness of 1...
February 18, 2018: Beijing da Xue Xue Bao. Yi Xue Ban, Journal of Peking University. Health Sciences
Yanju Wu, Anxing Zhou, Huimin Yang, Fei Wang, Kui Lu
In this work, a three dimensional (3D) graphene-nitrogen doped carbon nanotubes (G-NCNTs) network was successfully fabricated on the surface of a glassy carbon (GC) electrode using the pulse potential method (PPM) in a graphene oxide-nitrogen doped carbon nanotubes (GO-NCNTs) dispersion. The morphological and characteristics of GO-NCNTs and G-NCNTs nanocomposites were investigated by atomic force microscopy (AFM), scanning electron microscopy (SEM), UV-vis spectroscopy, Raman spectroscopy, and electrochemical experiments...
February 23, 2018: Materials
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