725 results on '"3d scanner"'
Search Results
2. Stationary 3D Scanning System for IoT Applications.
- Author
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Kowalski, Miłosz, Rybarczyk, Dominik, and Milecki, Andrzej
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REVERSE engineering ,PLANT maintenance ,SCANNING systems ,ELECTRONIC systems ,POINT cloud - Abstract
In various types of industrial applications, such as reverse engineering, machine operation, technical metrology, or modern factory maintenance, it is important to have systems that enable the quick and easy scanning of selected mechanical parts. This study presents the design process and analysis of a low-cost, 3D scanning system which can be used in industrial applications. The system collects point cloud data using an infrared distance sensor based on optical triangulation, controlled by a 32-bit microcontroller. Communication with the system is enabled through a serial interface and a dedicated window application, allowing users to monitor and adjust scanning parameters. The output data in the form of a point cloud are saved in a text file in the scanner's controller memory and then sent wirelessly to an external device, e.g., cloud and/or a diagnostic controller. The electronic system is equipped with a radio module that can be used to communicate with other devices in line with the idea of the Internet of Things and the concept of Industry 4.0. The results of the study are based on the accuracy of the three-dimensional digitization of the tested object and on the determination of the average measurement uncertainty. [ABSTRACT FROM AUTHOR]
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- 2024
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3. Development and Validation of a Point Cloud Data Processing Algorithm for Obstacle Recognition in Double Hull Block
- Author
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Sol Ha and Namkug Ku
- Subjects
3d scanner ,double hull block ,lidar ,point cloud ,obstacle detection ,Ocean engineering ,TC1501-1800 - Abstract
Shipyards have recently been experiencing severe labor shortages, prompting increased adoption of production automation systems to mitigate this issue. This paper introduces a point cloud data acquisition and processing system designed to support automation operations within double-hull block environments. The acquisition system utilizes LiDAR sensors and is built as a portable device capable of conducting 360-degree scans inside double-hull blocks. The processing system integrates the RANSAC algorithm for plane recognition and a voxelization algorithm for object detection, enabling accurate identification of obstacles within the double-hull block. To validate the system, a full-scale test bench was constructed to replicate actual working conditions. Experimental results indicated that the system could detect the positions of various obstacles within the test bench with an accuracy of up to 100 mm, which is sufficient for the implementation of automation systems. The findings from this research are expected to facilitate the adoption of production automation in shipyards, enhancing productivity and addressing labor shortages in the industry.
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- 2024
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4. Foam density measurement using a 3D scanner.
- Author
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Errichiello, Fabrizio, Amato, Daniele, Penati, Mario, and Di Maio, Ernesto
- Subjects
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VOLUME measurements , *SCANNING systems , *FOAM , *FLOTATION , *SAMPLE size (Statistics) - Abstract
In this work, we used a 3D scanner for the volume measurement of foamed samples, a long-standing problem in the density evaluation of foams. The 3D scanning density measurement method can be selected as an alternative to or in combination with well-established, classical methods that involve the use of instruments like a caliper, a pycnometer, or other devices based on displacement or flotation principles. In particular, the classical methods show some limitations when the foamed sample geometry is irregular, when the polymer is highly hygroscopic, and when it has open porosities. We have tested numerous foamed samples of different sizes, shapes, densities, materials, and morphologies. We utilized different 3D scanner configurations for their volume measurement and compared the results with geometrical and displacement methods, when possible. Results showed that the proposed method is highly accurate, reproducible, and simple, although some specific precautions should be put in place to avoid misinterpretation by the shape-reconstructing software. [ABSTRACT FROM AUTHOR]
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- 2024
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5. Comparison of accuracy and speed between plaster casting, high‐cost and low‐cost 3D scanners to capture foot, ankle and lower leg morphology of children requiring ankle‐foot orthoses.
- Author
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Farhan, Muhannad, Wang, Joyce Zhanzi, Warncke, Rachael, Cheng, Tegan Laura, and Burns, Joshua
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CHILD patients , *PLASTER , *MOVEMENT disorders , *SCANNING systems , *ORTHOPEDIC apparatus , *ANKLE , *FOOT - Abstract
Background: Traditional plaster‐cast fabrication of an ankle‐foot orthosis (AFO), although robust, is time‐consuming and cumbersome. 3D scanning is quickly gaining attention as an alternative to plaster casting the foot and ankle region for AFO fabrication. The aim of this study was to assess the accuracy and speed of two high‐performing 3D scanners compared with plaster casting in pediatric patients requiring an AFO. Methods: Ten participants (mean age 10.0 ± 3.9 years) prescribed AFOs for a movement disorder were 3D scanned with the high‐cost Artec Eva (Eva) and low‐cost Structure Sensor II (SSII) using one‐person (1p) and two‐person (2p) protocols. Accuracy and speed for both 3D scanners were compared with corresponding plaster cast measures (≤5% acceptable difference). Bland and Altman plots were generated to show mean bias and limits of agreement. Results: Overall, Eva and SSII were accurate for foot, ankle, and lower leg key clinical landmarks (Eva‐1p: 4.4 ± 7.3%; Eva‐2p: 3.2 ± 7.5%; SSII‐1p: 0.6 ± 7.4%; SSII‐2p: 0.7 ± 8.2%). Bland and Altman plots for the SSII demonstrated lower biases for 1p (bias 0.5 mm, LoA: −12.4–13.5 mm) and 2p (0.4 mm, LoA: −11.4–12.2 mm) protocols compared with Eva for 1p (bias 2.3 mm, LoA: −8.0–12.7 mm) and 2p (1.8 mm, LoA: −10.7–14.3 mm) protocols. The SSII 2p protocol was the fastest 3D scanning method (26.4 ± 11.1 s). Conclusions: The high‐cost Eva and low‐cost SSII 3D scanners using the 1p and 2p protocols produced comparable accuracy and faster capture of key clinical landmarks compared with plaster cast measures for the fabrication of AFOs in pediatric patients. [ABSTRACT FROM AUTHOR]
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- 2024
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6. Development of time-series point cloud data changes and automatic structure recognition system using Unreal Engine
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Kato, Toru, Takahashi, Hiroki, Yamashita, Meguru, Doi, Akio, and Imabuchi, Takashi
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- 2024
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7. Comparing the accuracy of crown fitting between milling and 3D printing techniques using CAD/CAM technologies.
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Alhamoudi, Fahad Hussain
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DENTAL crowns , *THREE-dimensional printing , *CAD/CAM systems , *RAPID prototyping , *DENTURES - Abstract
BACKGROUND: The accuracy of dental crowns is crucial for their longevity and effectiveness. OBJECTIVE: This study aims to investigate how the precision of crowns is affected by two different fabrication methods, either subtractive (milling) or additive (3D printing), within computer-aided design/computer-aided manufacture (CAD/CAM) technology. METHODS: A standardised digital scan of a maxillary first molar with a shoulder margin (.stl file) was used to design and fabricate crowns through both subtractive (milling) and additive (3D printing) processes. The crowns' marginal and internal fits were assessed comprehensively. Statistical analysis, including two-way ANOVA and independent t-tests, revealed significant differences in fitting accuracy between the two methods. RESULTS: Crowns produced via 3D printing demonstrated superior fitting with minimal marginal (14 ± 5 μ m) and internal discrepancies (22 ± 5 μ m) compared to milling (marginal: 22 ± 4 μ m, internal: 23 ± 3 μ m), indicating a statistically significant advantage in precision ( p s ⩽ 0.022 for marginal fit). CONCLUSION: The findings suggest that 3D printing may offer a more accurate alternative to milling in the fabrication of digital dental prostheses, potentially revolutionising the field with its enhanced precision capabilities. [ABSTRACT FROM AUTHOR]
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- 2024
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8. Stress-strain analysis of steel S235JRH pipe ring tensile specimens using 3D optical methods.
- Author
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Travica, Milan, Mitrović, Nenad, Petrović, Aleksandar, Jevtić, Ivana, and Milošević, Miloš
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STEEL pipe , *THERMAL imaging cameras , *DIGITAL image correlation , *STEEL analysis , *STRAINS & stresses (Mechanics) , *INFRARED cameras - Abstract
Various pipe production procedures, including the construction of seamless pipes using a shaft with the conical tip in the oil industry, require data on the circumferential strain and stress state of the pipe. A method for measuring the displacement, strain and stress behavior of a pipe ring tensile specimen (PRTS) in the hoop direction is what this study's goal was to develop, as there was a lack of a standardized testing process. For the study, five single S235JRH steel PRTS were tested. In the paper, it is presented how to test S235JRH steel PRTS using a Digital Image Correlation method, Thermal Imaging camera, and 3D scanner. A specially designed steel tool with two D blocks was developed for testing steel PRTS. The strain progression was documented using the 3D Digital Image Correlation method. Using a thermographic camera, an attempt was made to analyze the change in the temperature field of the PRTS during the test. All the specimens were subjected to 3D scanning to verify the cross-sectional geometry of the PRTS after a fracture. Fractures of all Single PRTS occurred in the break zone and almost identical places. The deviation value for the Experimental Ultimate strength value (true stress value) higher than the theoretical Ultimate strength value. Deviation value for the Experimental 0.2% Offset Yield Strength value is higher than the theoretical value. The results of the analysis of cross-sectional dimensions revealed a more significant variation in the thickness of the PRTS compared to its width. A potential area of literature review is the application of a high-resolution thermal imaging camera and the analysis of the stress state of the material using it. [ABSTRACT FROM AUTHOR]
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- 2024
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9. Development of YOLOv8 and Segment Anything Model Algorithm-Based Hanok Object Detection Model for Sustainable Maintenance of Hanok Architecture.
- Author
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Shin, Byeong-Uk
- Abstract
A Hanok refers to a traditional Korean architectural structure. Construction structures undergo gradual, rather than instantaneous, transformations due to material degradation and deterioration in joint durability. Moreover, the detection of a structural problem by a nonexpert has severe implications for the safety of the structure. In particular, the precise effects of natural disasters, including storms, earthquakes, heavy snowfall, and structural defects, on structures are hard to determine. Additionally, manuals are limited by their reliance on quantitative assessments, which can pose difficulties for nonspecialists when it comes to recording numerical data. To solve this problem, 3D scanners have been widely employed in evaluating Hanoks, particularly those assigned as cultural heritage by the government. While those assigned as cultural heritage assets are systematically managed by experts and through budgets, the management system for Hanoks inhabited by the public has been overlooked. To fill this gap, this study focused on digital devices that are accessible to nonexperts as replacements for professional 3D scanners. Specifically, data from photos of a Hanok taken with smartphones were extracted to generate objective numerical data. AI training data for Hanoks were used to train the YOLOv8 algorithm and Segment Anything Model (SAM). The leaning values of columns, which constitute a fundamental structural component of a Hanok, were calculated using photographs that precisely captured the columns. The direction and distance of the column's movement were extracted for visualization. To ensure the reliability of these values, the Hanok under investigation was 3D-scanned. Comparing the numerical values revealed a negligible margin of error, which confirmed the reliability of the photographic data values. Five-tier safety states (good, observation, caution, danger, and very dangerous) were defined based on the column movement distance by analyzing the real measurement data of government-managed Hanoks and used to visualize the structural condition of Hanoks. Therefore, nonexperts can determine the structural safety of a Hanok using objective numerical data, even in situations where its progressive deformation is not readily apparent. Objective numerical analysis based on reliably collected data allows nonexperts to accurately diagnose structural safety, thus facilitating prompt and suitable actions. The results of this study can serve to enhance the stability and longevity of Hanok structures, thus facilitating sustainable maintenance and management. [ABSTRACT FROM AUTHOR]
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- 2024
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10. Interaction Between Drying Shrinkage and Hardening of Geopolymers
- Author
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Thuilliez, H., Lanos, C., Phelipot-Mardelé, A., Mauvoisin, G., di Prisco, Marco, Series Editor, Chen, Sheng-Hong, Series Editor, Vayas, Ioannis, Series Editor, Kumar Shukla, Sanjay, Series Editor, Sharma, Anuj, Series Editor, Kumar, Nagesh, Series Editor, Wang, Chien Ming, Series Editor, Cui, Zhen-Dong, Series Editor, Ha-Minh, Cuong, editor, Pham, Cao Hung, editor, Vu, Hanh T. H., editor, and Huynh, Dat Vu Khoa, editor
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- 2024
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11. Comparison of accuracy and speed between plaster casting, high‐cost and low‐cost 3D scanners to capture foot, ankle and lower leg morphology of children requiring ankle‐foot orthoses
- Author
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Muhannad Farhan, Joyce Zhanzi Wang, Rachael Warncke, Tegan Laura Cheng, and Joshua Burns
- Subjects
3D scanner ,accuracy ,ankle foot orthosis ,foot measurement ,Diseases of the musculoskeletal system ,RC925-935 - Abstract
Abstract Background Traditional plaster‐cast fabrication of an ankle‐foot orthosis (AFO), although robust, is time‐consuming and cumbersome. 3D scanning is quickly gaining attention as an alternative to plaster casting the foot and ankle region for AFO fabrication. The aim of this study was to assess the accuracy and speed of two high‐performing 3D scanners compared with plaster casting in pediatric patients requiring an AFO. Methods Ten participants (mean age 10.0 ± 3.9 years) prescribed AFOs for a movement disorder were 3D scanned with the high‐cost Artec Eva (Eva) and low‐cost Structure Sensor II (SSII) using one‐person (1p) and two‐person (2p) protocols. Accuracy and speed for both 3D scanners were compared with corresponding plaster cast measures (≤5% acceptable difference). Bland and Altman plots were generated to show mean bias and limits of agreement. Results Overall, Eva and SSII were accurate for foot, ankle, and lower leg key clinical landmarks (Eva‐1p: 4.4 ± 7.3%; Eva‐2p: 3.2 ± 7.5%; SSII‐1p: 0.6 ± 7.4%; SSII‐2p: 0.7 ± 8.2%). Bland and Altman plots for the SSII demonstrated lower biases for 1p (bias 0.5 mm, LoA: −12.4–13.5 mm) and 2p (0.4 mm, LoA: −11.4–12.2 mm) protocols compared with Eva for 1p (bias 2.3 mm, LoA: −8.0–12.7 mm) and 2p (1.8 mm, LoA: −10.7–14.3 mm) protocols. The SSII 2p protocol was the fastest 3D scanning method (26.4 ± 11.1 s). Conclusions The high‐cost Eva and low‐cost SSII 3D scanners using the 1p and 2p protocols produced comparable accuracy and faster capture of key clinical landmarks compared with plaster cast measures for the fabrication of AFOs in pediatric patients.
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- 2024
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12. Volumetric analysis after caries excavation with caries detecting dyes and chemomechanical caries removal agents using 3D scanner-a randomised clinical trial
- Author
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Roja Bastia, Shashirekha Govind, Ali A. Assiry, Noura Abdulaziz Alessa, Mohammed Abdul Kader, Adbul Habeeb Adil, and Mohmed Isaqali Karobari
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Dental caries ,Volumetric analysis ,Caries detecting dye ,3D scanner ,Chemomechanical caries removal ,Dentistry ,RK1-715 - Abstract
Abstract Aim This research aimed to use an extra-oral 3D scanner for conducting volumetric analysis after caries excavation using caries-detecting dyes and chemomechanical caries removal agents in individuals with occlusal and proximal carious lesions. Methods Patients with occlusal (A1, A2, A3) and proximal carious lesions (B1, B2, B3) were treated with the conventional rotary technique, caries detecting dyes (CDD) and chemomechanical caries removal (CMCR) method on 90 teeth (n = 45 for each). Group A1, B1: Excavation was performed using diamond points. Group A2, B2: CDD (Sable Seek™ caries indicator, Ultradent) was applied and left for 10 s, and then the cavity was rinsed and dried. For caries removal, diamond points or excavators were used. Group A3 and B3: BRIX3000 papain gel was applied with a micro-brush for 20 s and was activated for 2 min, and then the carious tissue was removed with a sharp spoon excavator. Post-excavation cavity volume analysis was performed using a 3D scanner. The time required and the verbal pain score (VPS) for pain were scored during excavation. Post-restoration evaluation was performed at 1, 3, and 6 months FDI (Federation Dentaire Internationale) criteria. Results Comparison of age, time and volume with study groups were made using Independent Sample’ t’ test and one-way analysis of variance (ANOVA) for two and more than two groups, respectively. Using Cohen’s Kappa Statistics, evaluators 1 and 2 agreed on caries removal status aesthetic, functional and biological properties at different follow-ups. The chi-square test revealed that the rotary groups [A1(2.5 ± 0.4 min) B1(4.0 ± 0.4 min)] had significantly less (p = 0.000) mean procedural time than CDD [A2(4.5 ± 0.4 min) B2(5.7 ± 0.4 min)] and CMCR [A3(5.4 ± 0.7 min) B3(6.2 ± 0.6 min)] groups. The CMCR group showed better patient acceptance and less pain during caries excavation than the rotary and CDD groups. CMCR group showed significantly less mean caries excavated volume(p = 0.000). Evaluation of restoration after 1-, 3-, and 6-month intervals was acceptable for all the groups. Conclusion Brix3000 helps effectively remove denatured teeth with less pain or sensitivity. The time required for caries removal was lowest in the rotary method and highest in the brix3000 group, while the volume of caries removed was the lowest for brix3000 and highest for the rotary group.
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- 2024
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13. Evaluation of digital and manual orthodontic diagnostic setups in non-extraction cases using ABO model grading system: an in-vitro study
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Sherwet Shakr, Ibrahim Negm, and Hatem Saifeldin
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Orthodontic diagnostic setup ,Digital models ,ABO model grading system ,3D printer ,3D scanner ,Dentistry ,RK1-715 - Abstract
Abstract Background To evaluate the outcome quality of manual and digital orthodontic diagnostic setups in non-extraction cases according to the American Board of Orthodontics model grading system and to calculate the laboratory time needed for orthodontic diagnostic setup construction. Methods The sample consisted of 60 pretreatment models of non-extraction orthodontic cases with age ranges of 18–30. The study models were duplicated and scanned with 3Shape R-750 scanner. Digital and manual diagnostic setups were constructed according to their respective treatment plans. Digital diagnostic setups were 3D printed and then both manual and digital setups were assessed using the modified American Board of Orthodontics Cast Radiograph evaluation score (ABO CRE), which includes alignment, marginal ridge, buccolingual inclination, occlusal contacts, occlusal relationships, interproximal contacts, and overjet. The laboratory time needed for orthodontic setups was measured in minutes. Results The total ABO CRE score of the digital diagnostic setup group (5.93 ± 2.74) was significantly lower than that of the manual diagnostic setup group (13.08 ± 3.25). The manual diagnostic setup had significantly larger scores in marginal ridge, overjet, overbite, buccolingual inclination, occlusal relationship, and total scores (P
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- 2024
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14. Stationary 3D Scanning System for IoT Applications
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Miłosz Kowalski, Dominik Rybarczyk, and Andrzej Milecki
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3D scanning ,3D scanner ,reverse engineering ,point cloud ,scanning system ,IoT ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
In various types of industrial applications, such as reverse engineering, machine operation, technical metrology, or modern factory maintenance, it is important to have systems that enable the quick and easy scanning of selected mechanical parts. This study presents the design process and analysis of a low-cost, 3D scanning system which can be used in industrial applications. The system collects point cloud data using an infrared distance sensor based on optical triangulation, controlled by a 32-bit microcontroller. Communication with the system is enabled through a serial interface and a dedicated window application, allowing users to monitor and adjust scanning parameters. The output data in the form of a point cloud are saved in a text file in the scanner’s controller memory and then sent wirelessly to an external device, e.g., cloud and/or a diagnostic controller. The electronic system is equipped with a radio module that can be used to communicate with other devices in line with the idea of the Internet of Things and the concept of Industry 4.0. The results of the study are based on the accuracy of the three-dimensional digitization of the tested object and on the determination of the average measurement uncertainty.
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- 2024
- Full Text
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15. Evaluation of digital and manual orthodontic diagnostic setups in non-extraction cases using ABO model grading system: an in-vitro study
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Shakr, Sherwet, Negm, Ibrahim, and Saifeldin, Hatem
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- 2024
- Full Text
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16. Volumetric analysis after caries excavation with caries detecting dyes and chemomechanical caries removal agents using 3D scanner-a randomised clinical trial
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Bastia, Roja, Govind, Shashirekha, Assiry, Ali A., Alessa, Noura Abdulaziz, Kader, Mohammed Abdul, Adil, Adbul Habeeb, and Karobari, Mohmed Isaqali
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- 2024
- Full Text
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17. Application of augmented reality models of canine skull in veterinary anatomical education.
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Jiang, Nan, Jiang, Zhongling, Huang, Yufeng, Sun, Mingju, Sun, Xuejing, Huan, Yanjun, and Li, Fangzheng
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Veterinary anatomy plays a crucial role in the curriculum for veterinary medicine and surgery. The integration of modern information technology in veterinary education can greatly benefit from innovative tools such as augmented reality (AR) applications. The aim of this study was to develop an accurate and interactive three‐dimensional (3D) digital model of an animal skull using AR technology, aiming to enhance the learning of skull anatomy in veterinary anatomy education. In this study, a canine skull specimen was isolated, and the skull bones were scanned using a structured light scanner to create a 3D digital model of the canine skull, which was found to be indistinguishable from the original specimen by measurement of skull proportions. Furthermore, the interactive AR model of the canine skull, displayed using Unity3D, was subjected to testing and evaluation by 60 first‐year veterinary medical students attending the gross anatomy of the animal. The students were divided into two groups: the traditional group and AR group. Both groups completed an objective test and a questionnaire. The evaluation of learning effectiveness in the test revealed no significant difference between the traditional group (which learned using textbooks and a canine skull specimen) and AR group (which learned using AR tools). However, in the questionnaire, students displayed high enthusiasm and interest in using the AR tool. Therefore, the application of AR tools can improve students' motivation for learning and enhance the comprehension of anatomical structures in three dimensions. Furthermore, this study exemplifies the use of AR as an auxiliary tool for teaching and learning in veterinary anatomy education. [ABSTRACT FROM AUTHOR]
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- 2024
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18. A Review on 3D Scanners Studies for Producing Customized Orthoses.
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Silva, Rui, Silva, Bruna, Fernandes, Cristiana, Morouço, Pedro, Alves, Nuno, and Veloso, António
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ORTHOPEDIC apparatus , *SCANNING systems , *MEDICAL equipment , *FOOT orthoses , *HUMAN body , *COMPUTED tomography , *CUSTOMIZATION - Abstract
When a limb suffers a fracture, rupture, or dislocation, it is traditionally immobilized with plaster. This may induce discomfort in the patient, as well as excessive itching and sweating, which creates the growth of bacteria, leading to an unhygienic environment and difficulty in keeping the injury clean during treatment. Furthermore, if the plaster remains for a long period, it may cause lesions in the joints and ligaments. To overcome all of these disadvantages, orthoses have emerged as important medical devices to help patients in rehabilitation, as well as for self-care of deficiencies in clinics and daily life. Traditionally, these devices are produced manually, which is a time-consuming and error-prone method. From another point of view, it is possible to use imageology (X-ray or computed tomography) to scan the human body; a process that may help orthoses manufacturing but which induces radiation to the patient. To overcome this great disadvantage, several types of 3D scanners, without any kind of radiation, have emerged. This article describes the use of various types of scanners capable of digitizing the human body to produce custom orthoses. Studies have shown that photogrammetry is the most used and most suitable 3D scanner for the acquisition of the human body in 3D. With this evolution of technology, it is possible to decrease the scanning time and it will be possible to introduce this technology into clinical environment. [ABSTRACT FROM AUTHOR]
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- 2024
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19. Comparison of craniometric measurements of New Zealand rabbit (Oryctolagus cuniculus L.) using three‐dimensional scanner with digital calliper measurements: A methodological study.
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Koçyiğit, Ali and Demircioğlu, İsmail
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EUROPEAN rabbit , *FORAMEN magnum , *RABBITS , *SCANNING systems , *LABORATORY animals , *OPTICAL scanners , *SKULL - Abstract
As technology has developed in recent years, the use of three‐dimensional (3D) scanners and printers has become widespread in the medical field. However, since this field is new, all kinds of methodological and experimental related studies gain importance. This study aimed to identify the differences between the calliper measurements by determining the craniometric data on the models constructed by scanning the crania of New Zealand Rabbits (Oryctolagus cuniculus L.), preferred as experimental animals, with a three‐dimensional scanner. Therefore, a total of 12 New Zealand rabbits including 6 females and 6 males were used. After the crania that comprised the study material were macerated, they were subjected to 3D scanning. After the scanning process was completed, they were craniometrically measured both on the scanned models and by using a digital calliper. Analysis of the craniometric data of the 3D scanner showed that there was a difference between sexes at the level of p < 0.05 in widest length between the external acoustic meatus (WLBEAM), skull width and Foramen magnum height (FMH) parameters and cranial index data, and at the level of p < 0.001 in the largest nasal width (LNW) parameter. A statistical difference was found between sexes in frontal length, WLBEAM, LNW and FMH parameters and cranial index values in craniometric data collected with the digital calliper (p < 0.05). Consequently, the data collected in this study were found to be close to each other in both methods, suggesting that the 3D scanner may be used in morphometric studies. [ABSTRACT FROM AUTHOR]
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- 2024
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20. Submillimeter-Accurate Markerless Hand–Eye Calibration Based on a Robot's Flange Features.
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Đalić, Velibor, Jovanović, Vedran, and Marić, Petar
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OPTICAL scanners , *ROBOT vision , *CALIBRATION , *FLANGES , *LEAST squares , *ROBOTS , *OPTICAL sensors , *HUMAN fingerprints - Abstract
An accurate and reliable estimation of the transformation matrix between an optical sensor and a robot is a key aspect of the hand–eye system calibration process in vision-guided robotic applications. This paper presents a novel approach to markerless hand–eye calibration that achieves streamlined, flexible, and highly accurate results, even without error compensation. The calibration procedure is mainly based on using the robot's tool center point (TCP) as the reference point. The TCP coordinate estimation is based on the robot's flange point cloud, considering its geometrical features. A mathematical model streamlining the conventional marker-based hand–eye calibration is derived. Furthermore, a novel algorithm for the automatic estimation of the flange's geometric features from its point cloud, based on a 3D circle fitting, the least square method, and a nearest neighbor (NN) approach, is proposed. The accuracy of the proposed algorithm is validated using a calibration setting ring as the ground truth. Furthermore, to establish the minimal required number and configuration of calibration points, the impact of the number and the selection of the unique robot's flange positions on the calibration accuracy is investigated and validated by real-world experiments. Our experimental findings strongly indicate that our hand–eye system, employing the proposed algorithm, enables the estimation of the transformation between the robot and the 3D scanner with submillimeter accuracy, even when using the minimum of four non-coplanar points for calibration. Our approach improves the calibration accuracy by approximately four times compared to the state of the art, while eliminating the need for error compensation. Moreover, our calibration approach reduces the required number of the robot's flange positions by approximately 40%, and even more if the calibration procedure utilizes just four properly selected flange positions. The presented findings introduce a more efficient hand–eye calibration procedure, offering a superior simplicity of implementation and increased precision in various robotic applications. [ABSTRACT FROM AUTHOR]
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- 2024
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21. Evaluation of the Influence of Vestibular Surface Morphology Variability of Maxillary Incisors on Torque: Examination Using 3D Intraoral Scans.
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Wajda, Michał, Lis, Joanna, Minch, Liwia, and Kawala, Beata
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INCISORS ,SURFACE morphology ,TORQUE ,CORRECTIVE orthodontics ,THREE-dimensional modeling ,MAXILLA ,OPTICAL scanners - Abstract
Featured Application: During bracket positioning, the individual variation in the tooth surface should be considered and evaluated, because the results of this work showed essential morphological differentiation of the CrVS of the maxillary incisors. Proper torque is an important element of orthodontic treatment. There are many factors affecting effective torque expression, e.g., the interplay between an archwire and a bracket, the precision during bracket positioning, and the morphology of the crown vestibular surface (CrVS) of the tooth. Our study focused on the impact of the maxillary incisor CrVS morphology on the torque exerted by the archwire–bracket interplay. Three-dimensional models of 50 patients acquired through the use of an intraoral scanner were used to examine the four maxillary incisors. A total of 200 teeth were examined. The influence of the tooth crown shape on the bracket position and the related torque change was analyzed with Ortho Analyzer software 2015 (3Shape, Copenhagen, Denmark). All calculations were made for full size archwires. Central incisors showed less variability in their vestibular surfaces than lateral incisors. For the central incisors, the mean values of the additional palatal root torque ranged from 0.6° to 1.6°. For the laterals, the mean values ranged from 1.4° of additional vestibular root torque to 3.5° of additional palatal root torque. The results showed essential morphological differentiation of the CrVS of the maxillary incisors. Therefore, when the bracket is positioned, the individual variation in the tooth surface should be considered and evaluated. [ABSTRACT FROM AUTHOR]
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- 2024
- Full Text
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22. BIOSKAIDŽIŲ POLIMERŲ PANAUDOJIMAS ORTOPEDINIŲ TECHNINIŲ PRIEMONIŲ GAMYBOJE.
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KUNCĖ, NAITAS, KRUKAUSKAS, IGNAS, and SINKUTĖ, BIRUTĖ
- Abstract
Synthetic polymers are used in the manufacture of orthopaedic technical devices. Polypropylene and polyethylene are the most commonly used, which have good physical and mechanical properties but pose a significant threat to the environment and are very difficult to recycle and dispose of. A number of biodegradable thermoplastics are now being produced worldwide and could be used as an alternative to non-organic materials used in orthopaedic technology. This study reviews the use of biodegradable polymers in the manufacture of orthopaedic devices. The diversity, perspectives and potential of existing thermoplastics are analysed through an analysis of the scientific literature. A review of existing materials used in orthopaedic devices has shown that they are very harmful to the environment and should be replaced by biodegradable materials, therefore reducing environmental pollution. A review of the use of polylactide (PLA) in orthopaedic technology has shown that it can be used in a variety of ways, such as additive manufacturing (3D printing), the "sandwich" principle using a vacuum press, and in the production of customised shoe insoles. [ABSTRACT FROM AUTHOR]
- Published
- 2024
23. Does the traditional or digital dental model measurement method affect the results?: A validation study
- Author
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Nurver Karslı, Kutay Çava, Merve Gonca, and Zehra Yurdakul
- Subjects
3d scanner ,reliability ,digital models ,Dentistry ,RK1-715 - Abstract
Objective: The aim of this study is to evaluate the accuracy, reliability and reproducibility of measurements made on digital models obtained using OrthoAnalyzer (3Shape, Copenhagen, Denmark) and Materialize 3 matic (MIMICS , Leuven, Belgium) software by comparing them with measurements made on dental plaster models. Methods: The teeth of 50 individuals were measured and plaster models were obtained. In addition, digital images were obtained from the patients with Trios intraoral scanner. A total of 30 linear measurements were made using OrthoAnalyzer and Materialize 3 matic software, including the mesiodistal width of the teeth, arch perimeter, intercanine and intermolar distances. All measurements were made by two different examiners. For the first and second measurements of the first examiner, intraexaminer reliability was calculated using intraclass correlation coefficients (ICCs), two way mixed model, consistency type. Results: The largest mean difference between Materialize 3 matic and caliper measurements was -0.136 mm in maxillary right first premolar and maxillary left lateral incisor. The smallest mean difference was 0.0029 mm in the mandibular left lateral incisor. In transverse measurements, the largest mean difference was found in the upper intercanine distance of 0.117 mm, and the smallest mean difference was 0.0086 mm in the upper intermolar distance. The largest mean difference between OrthoAnalyzer and caliper measurements was 0.107 mm in the maxillary right lateral incisor, and the smallest mean difference was 0.0049 mm in the maxillary left lateral incisor. Conclusions: Linear distance measurements with three-dimensional digital models are a valid, reliable and reproducible method compared to plaster models.
- Published
- 2023
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- View/download PDF
24. Correlation between low skeletal muscle index and 3D anthropometric data measured by 3D body scanner: screening sarcopenia
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Kyu Wan Kim, Yongsoo Park, Yohan Lee, and Minjoon Cho
- Subjects
sarcopenia ,skeletal muscle index ,bio-impedance analysis ,screening ,3D scanner ,3D anthropometry ,Medicine (General) ,R5-920 - Abstract
BackgroundThe screening tools for sarcopenia are measuring calf circumference, SARC-F or SPPB. However, not all of these tools have high sensitivity, specificity, and low margins of error. This research investigates potential of 3D anthropometry of the lower extremities on screening of sarcopenia.MethodsFrom October 2022 to February 2023, we retrospectively analyzed results of 3D body scanner and bio-impedance analysis for patients aged 45 to 85 at risk of sarcopenia. The 3D scanner measured the surface and volume values of both thighs and calves. When skeletal muscle index (SMI) is less than 5.7, patients were classified to Low SMI group, indicative of sarcopenia.ResultsA total six out of 62 patients were classified to Low SMI group, showing significantly lower values of right, left, mean calf volumes and mean calf surface than the other patients (right calf volume 2.62 L vs. 3.34 L, p = 0.033; left calf volume 2.62 L vs. 3.25 L, p = 0.044; mean calf volume 2.62 L vs. 3.29 L, p = 0.029; mean calf surface 0.12 m2 vs. 0.13 m2, p = 0.049). There was no statistical difference in thigh volume and surface. Through AUC-ROC analysis, mean calf volume was the most significant cut-off value (right calf volume 2.80 L, AUC = 0.768; left calf volume 2.75 L, AUC = 0.753; mean calf volume 3.06 L, AUC = 0.774; mean calf surface 0.12 m2, AUC = 0.747).ConclusionThe calf volume and surface values have significant relationship with low SMI, and the mean calf volume was the most significant cut-off screening value for Low SMI. The 3D scanner demonstrated its value as a new means for screening sarcopenia.
- Published
- 2024
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25. Optimal Pre-processing of Laser Scanning Data for Indoor Scene Analysis and 3D Reconstruction of Building Models.
- Author
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Kim, Minju and Kim, Harim
- Abstract
The large-scale point cloud data representing buildings should be prudently pre-processed and down-sampled prior to post-data processing activities, such as data segmentation or classification and indoor scene analysis, and visualization of the processed results as three-dimensional (3D) digital models. However, current pre-processing tasks and down-sampling procedures encountered the challenge of preserving the geometric and semantic features of the scanned object and contributing to accurate 3D reconstruction due to the loss of significant features on buildings. Therefore, this paper proposed a framework that pre-processes unstructured laser scanning data to optimize the efficiency of data processing activities and the accuracy of the produced output, i.e., reconstructed 3D building models. The pre-processing framework includes building the topology of the unstructured dataset, down-sampling the raw data through an improved voxel-based approach, and performing indoor scene analysis such as normal estimation, point alignment, and data classification. The experimental results verified that the proposed framework efficiently pre-processes the input data and preserves the geometric characteristics of the digital models with high accuracy, thereby supporting reliable 3D reconstruction for various applications. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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- View/download PDF
26. A 3D scanning based image processing technique for measuring the sequence of intersecting lines
- Author
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Asicioglu, Faruk, Gelir, Ali, Yilmaz, Aysegul Sen, De Kinder, Jan, Kadi, Omer F., Ozdemir, Onur B., Pekacar, Ilgim, Sasun, Ugur, Ciftci, Saltuk B., and Dayioglu, Nurten
- Published
- 2024
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27. Application and Advantage of 3D Body Scanning in the Ergonomic Design of a Sitting Workplace
- Author
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Šajatović, Blaženka Brlobašić, Petrak, Slavenka, Kacprzyk, Janusz, Series Editor, Gomide, Fernando, Advisory Editor, Kaynak, Okyay, Advisory Editor, Liu, Derong, Advisory Editor, Pedrycz, Witold, Advisory Editor, Polycarpou, Marios M., Advisory Editor, Rudas, Imre J., Advisory Editor, Wang, Jun, Advisory Editor, Salopek Čubrić, Ivana, editor, Čubrić, Goran, editor, Jambrošić, Kristian, editor, Jurčević Lulić, Tanja, editor, and Sumpor, Davor, editor
- Published
- 2023
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- View/download PDF
28. Model of Decision Support System with Artificial Intelligence for Aircraft Fuselage Damage Assessment
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Bodrova, Irina, Kacprzyk, Janusz, Series Editor, Gomide, Fernando, Advisory Editor, Kaynak, Okyay, Advisory Editor, Liu, Derong, Advisory Editor, Pedrycz, Witold, Advisory Editor, Polycarpou, Marios M., Advisory Editor, Rudas, Imre J., Advisory Editor, Wang, Jun, Advisory Editor, Kabashkin, Igor, editor, Yatskiv, Irina, editor, and Prentkovskis, Olegas, editor
- Published
- 2023
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29. Determining optimal lighting in 3D scanner for hand foot static anthropometric measurements
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Novie Susanto, Manik Mahachandra, Wiwik Budiawan, Ega Rizkiyah, and Cintya Dema Apsari
- Subjects
static anthropometry ,3D scanner ,precision ,trueness ,efficiency ,Engineering (General). Civil engineering (General) ,TA1-2040 - Abstract
AbstractThe lighting condition is critical in the anthropometric scanning process. Optimal lighting condition affects the time and precision. The current study sought to determine the optimal light for measuring the static anthropometric dimensions of feet and hands based on the precision, trueness, and efficiency of EinScan Pro 2X Plus. Three conditions of the scanning process were Light Zero Light/ZL: 5–50 lux, Normal Light/NL: 50–100 lux, and Room Light/RL: 100–200 lux. The data collected and analyzed were 3D model mesh data (point clouds), which were then processed using CAD software for deviation analysis. The precision variable was computed using the pooled standard deviation ([Formula: see text]) value. The Absolute Error (AE) and Absolute Percentage Error (APE) were used to calculate the trueness variable. The efficiency aspect was measured based on the average value of measurement time. The optimal lighting condition was ZL, which was determined using a simple additive weighting method. The precision of the hand in [Formula: see text] value was 1.25 mm while the foot precision was 0.92 mm. The hand trueness in AE value was 1.73 ± 1.33, while the foot trueness was 1.34 ± 1.20 mm. The hand efficiency in time value was 273.94 s, and the foot efficiency were 272,94 s.
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- 2023
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30. Computer Vision on the Edge to Reduce Network Bandwidth Consumption and Computing Resources in Multi-view 3D Industrial Inspection without Hidden Surfaces.
- Author
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Escrivá, David Millán, Ruiz, Javier Tendillo, Carbó, Pau Garrigues, Santacruz, Andrés Martín Larroza, Gomariz, Guillermo Amat, Soler, Javier Perez, Guardiola, Jose Luis, and Perez-Cortes, Juan-Carlos
- Abstract
Industrial inspection industry requires high precision, fast and reliable systems, where images play a central role. These systems are composed by several hardware and also cyber-physical componentes where complexity increases when multiple heterogeneous sensor inputs are combined. Our 3D industrial inspection scanner is able to reconstruct complete objects without occlusion with use of multiple sensors and actuators using a complex software architecture. Our system allows increasing the throughput by removing the bottleneck network issue, decreasing network data transfer using a new edge systems architecture that segments and optimizes image transferring. Also, this work presents the results of applying technology developed during the FitOptiVis European ECSEL project. FitOptiVis will provide a reference architecture supporting composability built on suitable component abstractions and embedded sensing, actuation and processing devices adhering to those abstractions. The reference architecture will support design portability, on-line multi-objective quality and resource management and run-time adaptation guaranteeing system constraints and requirements based on platform virtualization. The FitOptiVis project will be applied to design the new architecture of the new edge components and develop the runtime system monitoring. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
31. Does the traditional or digital dental model measurement method affect the results?: A validation study.
- Author
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Karslı, Nurver, Yurdakul, Zehra, Gonca, Merve, and Çava, Kutay
- Subjects
SOFTWARE measurement ,LENGTH measurement ,INTRACLASS correlation ,DIGITAL images ,INCISORS - Abstract
The aim of this study is to evaluate the accuracy, reliability and reproducibility of measurements made on digital models obtained using OrthoAnalyzer (3Shape, Copenhagen, Denmark) and Materialize 3-matic (MIMICS
® , Leuven, Belgium) software by comparing them with measurements made on dental plaster models. The teeth of 50 individuals were measured and plaster models were obtained. In addition, digital images were obtained from the patients with Trios intraoral scanner. A total of 30 linear measurements were made using OrthoAnalyzer and Materialize 3-matic software, including the mesiodistal width of the teeth, arch perimeter, intercanine and intermolar distances. All measurements were made by two different examiners. For the first and second measurements of the first examiner, intraexaminer reliability was calculated using intra-class correlation coefficients (ICCs), two-way mixed model, consistency type. The largest mean difference between Materialize 3-matic and caliper measurements was -0.136 mm in maxillary right first premolar and maxillary left lateral incisor. The smallest mean difference was -0.0029 mm in the mandibular left lateral incisor. In transverse measurements, the largest mean difference was found in the upper intercanine distance of 0.117 mm, and the smallest mean difference was -0.0086 mm in the upper intermolar distance. The largest mean difference between OrthoAnalyzer and caliper measurements was 0.107 mm in the maxillary right lateral incisor, and the smallest mean difference was -0.0049 mm in the maxillary left lateral incisor. Linear distance measurements with three-dimensional digital models are a valid, reliable and reproducible method compared to plaster models. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
32. A simple anthropometric estimation formula for healthy female labourers’ leg volume
- Author
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Hsin-Hung Tu
- Subjects
leg volume ,3d scanner ,anthropometric estimation formula ,optoelectronic ,Biology (General) ,QH301-705.5 ,Human anatomy ,QM1-695 ,Physiology ,QP1-981 - Abstract
Background Leg volume (LV) is an important reference in nutrition, physiology in exercise, or clinical diagnosis. Therefore, how to evaluate LV easily and quickly with accuracy is important in these areas. Aim To develop a simple anthropometric estimation formula with ease of use and good accuracy for leg volume (LV) of female labourers. Subjects One hundred and thirty female labourers (110 subjects for formula regression procedure and 20 subjects for the comparison phase) were recruited as subjects with no reported leg surgery history, trauma, or deformity. Methods A set of 3 D scanners was used to measure the range data of each subject’s leg. Results The resultant LV estimation formula is LV = 0.215 × LL × CTH1.620 with R2 = 0.967, in which LL stands for leg length and CTH for circumference of thigh. Mean error of this LV estimation is 0.10% and much smaller than that of the previous study (25.11% with significant difference). Conclusion An anthropometric estimation formula for female labourers’ leg volume was developed in this study. Estimation mean error of this formula is much smaller than the one in the previous study. This formula is easy to use and shows good accuracy in estimating female labourers’ leg volume.
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- 2023
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33. The Influence of Carboxytherapy on Scar Reduction
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Stolecka-Warzecha A, Chmielewski Ł, Deda A, Śmich A, Lebiedowska A, and Wilczyński S
- Subjects
carboxytherapy ,scar ,3d scanner ,cutometer ,Dermatology ,RL1-803 - Abstract
Anna Stolecka-Warzecha,1 Łukasz Chmielewski,2 Anna Deda,3 Aleksandra Śmich,1 Agata Lebiedowska,1 Sławomir Wilczyński1 1Department of Basic Biomedical Science, Faculty of Pharmaceutical Sciences in Sosnowiec, Medical University of Silesia, Katowice, Poland; 2Department of Motion Organ Reconstruction Surgery, Provincial Specialist Hospital Megrez, Tychy, Poland; 3Department of Cosmetology, Faculty of Pharmaceutical Sciences in Sosnowiec, Medical University of Silesia, Katowice, PolandCorrespondence: Anna Stolecka-Warzecha, Department of Basic Biomedical Science, Faculty of Pharmaceutical Sciences in Sosnowiec, Medical University of Silesia, Kasztanowa 3, Sosnowiec, 41-205, Poland, Tel +48 603 069 908, Email astolecka@sum.edu.plIntroduction: Although it is not a new method, a carboxytherapy, which is based on intradermal or subcutaneous administration of controlled doses of CO2, is gaining more and more recognition among aesthetic medicine doctors, dermatologists and cosmetologists around the world. The consequence of applying carbon dioxide directly into tissues is associated with an immediate expansion of blood vessels, improvement of local blood supply, and, thus, tissue metabolism. It does also support natural regenerative processes. Oxygen and growth factors released from blood, within the area which undergoes treatment, stimulate fibroblasts to produce collagen and formation of new blood vessels also known as neovascularization. In addition to biochemical mechanisms, CO2 injection into the dermis or subcutaneous tissue leads to a mechanical effect exerted by pressure and flow of CO2 which is injected. It is of particular importance in scar treatments.Methods: Twelve mature scars were subjected to the carboxytherapy which was performed in people aged 23– 45 years. A small amount of heated, medical CO2 was injected till the moment a scar turns white. The applied flow rate equalled 100 mL/min (cc/min). Before and after a series of four treatments, the level of hydration, elasticity and colour of the skin were measured. A structured-light 3D scanner was used to determine an exact morphology of the examined scars. The 3D scanning device is seen as a sensitive and precise method of qualitative and quantitative assessment of a morphology of scars.Results: The results of the measurements performed showed a reduction in the surface of the analyzed changes, as well as proved the ability of CO2 to rebuild collagen fibres. The decrease in value of parameters, which have been obtained thanks to the kutometric examination, indicates softening and loosening of connective tissue. It does confirm the effectiveness of carboxytherapy.Keywords: carboxytherapy, scar, 3D scanner, cutometer
- Published
- 2022
34. Evaluating Cranial Growth in Japanese Infants Using a Three-dimensional Scanner: Relationship between Growth-related Parameters and Deformational Plagiocephaly
- Author
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Hiroshi MIYABAYASHI, Nobuhiko NAGANO, Shin HASHIMOTO, Katsuya SAITO, Risa KATO, Takanori NOTO, Mari SASANO, Koichiro SUMI, Atsuo YOSHINO, and Ichiro MORIOKA
- Subjects
infant ,cranial shape ,cephalic index ,growth ,3d scanner ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
In this study, we aimed to evaluate the longitudinal changes in the cranial shape of healthy Japanese infants using a three-dimensional scanner and construct a normal values database for the growth process. Preterm infants (gestational age < 37 weeks), infants with neonatal asphyxia (5-minute Apgar score of 5% was defined as deformational plagiocephaly. Changes in each parameter were examined using repeated-measures analysis of variance classified by sex and deformational plagiocephaly status. The rate of increase in each parameter was also examined. In total, 88 infants (45 boys and 43 girls) were included in this study. All growth-related parameters were noted to increase linearly with time. Sex differences were observed in all parameters except cranial length. Deformational plagiocephaly was found to have no effect on growth-related parameters. Cranial volume increased by 60% from 1 to 6 months of age. The growth almost uniformly influenced the rate of increase in volume in each coordinate axis direction. Overall, the mean trends in three-dimensional parameters in infants up to 6 months of age were obtained using a three-dimensional scanner. These trends could be used as a guide by medical professionals involved in cranioplasty.
- Published
- 2022
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35. Mechatronic Design and Experimental Research of an Automated Photogrammetry-Based Human Body Scanner.
- Author
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Trojnacki, Maciej, Dąbek, Przemysław, and Jaroszek, Piotr
- Subjects
- *
MECHATRONICS , *SCANNING systems , *HUMAN body , *STANDARD deviations , *EXPERIMENTAL design - Abstract
The article concerns the mechatronic design and experimental investigations of the HUBO automated human body scanning system. Functional problems that should be solved by using the developed scanning system are defined. These include reducing the number of sensors used while eliminating the need to rotate a human and ensuring the automation of the scanning process. Research problems that should be the subject of experimental research are defined. The current state of the art in the field of systems and techniques for scanning the human figure is described. The functional and technical assumptions for the HUBO scanning system are formulated. The mechanical design of the scanner, the hardware and information system architectures as well as the user's mobile application are presented. The method of operation of the scanning system and its innovative features are discussed. It is demonstrated that the developed solution of the scanning system allows the identified problems to be overcome. The methodology of the experimental research of the scanning system based on the photogrammetry technique is described. The results of laboratory studies with the use of dummies and experimental research with human participation are presented. The scope of the research carried out allows answers to the identified research problems related to the scanning of the human figure using the photogrammetry technique to be obtained. As part of laboratory tests using a measuring dummy, a mean error of 0.65 mm and standard deviation of the mean of 0.65 mm were obtained for the best scanner configuration. Research with human participation was carried out for the scanner version, in which the scanning time was 30 s, with the possibility of its reduction to 15 s. The results of studies using realistic dummies and with human participation were compared using the root mean square error parameter (RMSE) provided by the AliceVision framework, which was available for all analyzed objects. As a result, it was observed that these results are comparable, i.e., the RMSE parameter is equal to about 1 px. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
36. Submillimeter-Accurate Markerless Hand–Eye Calibration Based on a Robot’s Flange Features
- Author
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Velibor Đalić, Vedran Jovanović, and Petar Marić
- Subjects
markerless hand–eye calibration ,robot’s flange ,TCP ,point cloud ,3D scanner ,3D circle fitting ,Chemical technology ,TP1-1185 - Abstract
An accurate and reliable estimation of the transformation matrix between an optical sensor and a robot is a key aspect of the hand–eye system calibration process in vision-guided robotic applications. This paper presents a novel approach to markerless hand–eye calibration that achieves streamlined, flexible, and highly accurate results, even without error compensation. The calibration procedure is mainly based on using the robot’s tool center point (TCP) as the reference point. The TCP coordinate estimation is based on the robot’s flange point cloud, considering its geometrical features. A mathematical model streamlining the conventional marker-based hand–eye calibration is derived. Furthermore, a novel algorithm for the automatic estimation of the flange’s geometric features from its point cloud, based on a 3D circle fitting, the least square method, and a nearest neighbor (NN) approach, is proposed. The accuracy of the proposed algorithm is validated using a calibration setting ring as the ground truth. Furthermore, to establish the minimal required number and configuration of calibration points, the impact of the number and the selection of the unique robot’s flange positions on the calibration accuracy is investigated and validated by real-world experiments. Our experimental findings strongly indicate that our hand–eye system, employing the proposed algorithm, enables the estimation of the transformation between the robot and the 3D scanner with submillimeter accuracy, even when using the minimum of four non-coplanar points for calibration. Our approach improves the calibration accuracy by approximately four times compared to the state of the art, while eliminating the need for error compensation. Moreover, our calibration approach reduces the required number of the robot’s flange positions by approximately 40%, and even more if the calibration procedure utilizes just four properly selected flange positions. The presented findings introduce a more efficient hand–eye calibration procedure, offering a superior simplicity of implementation and increased precision in various robotic applications.
- Published
- 2024
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37. A Review on 3D Scanners Studies for Producing Customized Orthoses
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Rui Silva, Bruna Silva, Cristiana Fernandes, Pedro Morouço, Nuno Alves, and António Veloso
- Subjects
3D scanner ,orthoses ,photogrammetry ,structured light ,Chemical technology ,TP1-1185 - Abstract
When a limb suffers a fracture, rupture, or dislocation, it is traditionally immobilized with plaster. This may induce discomfort in the patient, as well as excessive itching and sweating, which creates the growth of bacteria, leading to an unhygienic environment and difficulty in keeping the injury clean during treatment. Furthermore, if the plaster remains for a long period, it may cause lesions in the joints and ligaments. To overcome all of these disadvantages, orthoses have emerged as important medical devices to help patients in rehabilitation, as well as for self-care of deficiencies in clinics and daily life. Traditionally, these devices are produced manually, which is a time-consuming and error-prone method. From another point of view, it is possible to use imageology (X-ray or computed tomography) to scan the human body; a process that may help orthoses manufacturing but which induces radiation to the patient. To overcome this great disadvantage, several types of 3D scanners, without any kind of radiation, have emerged. This article describes the use of various types of scanners capable of digitizing the human body to produce custom orthoses. Studies have shown that photogrammetry is the most used and most suitable 3D scanner for the acquisition of the human body in 3D. With this evolution of technology, it is possible to decrease the scanning time and it will be possible to introduce this technology into clinical environment.
- Published
- 2024
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38. Development of the Handheld Measuring Probe for a 3D Scanner
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Kupiec, Robert, Harmatys, Wiktor, Sanetra, Izabela, Składanowska, Katarzyna, Ostrowska, Ksenia, Cavas-Martínez, Francisco, Editorial Board Member, Chaari, Fakher, Series Editor, di Mare, Francesca, Editorial Board Member, Gherardini, Francesco, Series Editor, Haddar, Mohamed, Editorial Board Member, Ivanov, Vitalii, Series Editor, Kwon, Young W., Editorial Board Member, Trojanowska, Justyna, Editorial Board Member, Diering, Magdalena, editor, Wieczorowski, Michał, editor, Harugade, Mukund, editor, and Pereira, Alejandro, editor
- Published
- 2022
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39. Geometric Inspection in Surfboard Manufacturing by Using Reverse Engineering and 3D Inspection Tools
- Author
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Amezua, Xabier, Solaberrieta, Eneko, Garikano, Xabier, Perez, Angel, Fernandez, Florencio, Iturrate, Mikel, Cavas-Martínez, Francisco, Series Editor, Chaari, Fakher, Series Editor, di Mare, Francesca, Series Editor, Gherardini, Francesco, Series Editor, Haddar, Mohamed, Series Editor, Ivanov, Vitalii, Series Editor, Kwon, Young W., Series Editor, Trojanowska, Justyna, Series Editor, Cavas Martínez, Francisco, editor, Peris-Fajarnes, Guillermo, editor, Morer Camo, Paz, editor, Lengua Lengua, Ismael, editor, and Defez García, Beatriz, editor
- Published
- 2022
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40. Structural Stress and Strain Analysis Using a 3D Scanner
- Author
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Kljuno, Elvedin, Razić, Faruk, Mešić, Elmedin, Ćatović, Alan, Kacprzyk, Janusz, Series Editor, Gomide, Fernando, Advisory Editor, Kaynak, Okyay, Advisory Editor, Liu, Derong, Advisory Editor, Pedrycz, Witold, Advisory Editor, Polycarpou, Marios M., Advisory Editor, Rudas, Imre J., Advisory Editor, Wang, Jun, Advisory Editor, Ademović, Naida, editor, Mujčić, Edin, editor, Akšamija, Zlatan, editor, Kevrić, Jasmin, editor, Avdaković, Samir, editor, and Volić, Ismar, editor
- Published
- 2022
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41. Patient-specific Monte Carlo-based organ dose estimates in spiral CT via optical 3D body scanning and adaptation of a voxelized phantom dataset: proof-of-principle.
- Author
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Maddaloni, Francesca Saveria, Sarno, Antonio, Mettivier, Giovanni, Clemente, Stefania, Oliviero, Caterina, Ricciardi, Roberta, Varallo, Antonio, and Russo, Paolo
- Subjects
- *
IMAGING phantoms , *OPTICAL scanners , *COMPUTED tomography , *ABSORBED dose , *BODY size - Abstract
Objective. We present a method for personalized organ dose estimates obtained before the computed tomography (CT) exam, via 3D optical body scanning and Monte Carlo (MC) simulations. Approach. A voxelized phantom is derived by adapting a reference phantom to the body size and shape measured with a portable 3D optical scanner, which returns the 3D silhouette of the patient. This was used as an external rigid envelope for incorporating a tailored version of the internal body anatomy derived from a phantom dataset (National Cancer Institute, NIH, USA) matched for gender, age, weight, and height. The proof-of-principle was conducted on adult head phantoms. The Geant4 MC code provided estimates of the organ doses from 3D absorbed dose maps in the voxelized body phantom. Main results. We applied this approach for head CT scanning using an anthropomorphic voxelized head phantom derived from 3D optical scans of manikins. We compared the estimates of head organ doses with those provided by the NCICT 3.0 software (NCI, NIH, USA). Head organ doses differed up to 38% using the proposed personalized estimate and MC code, with respect to corresponding estimates calculated for the standard (non-personalized) reference head phantom. Preliminary application of the MC code to chest CT scans is shown. Real-time pre-exam personalized CT dosimetry is envisaged with adoption of a Graphics Processing Unit-based fast MC code. Significance. The developed procedure for personalized organ dose estimates before the CT exam, introduces a new approach for realistic description of size and shape of patients via voxelized phantoms specific for each patient. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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42. ARKEOLOJİK ESER BELGELEMELERİNDE TERSİNE MÜHENDİSLİK UYGULAMASI ÜZERİNE BİR ÇALIŞMA: BEÇİN KALESİ KAZISI KÜÇÜK ESERLERİ.
- Author
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ARDA, Göknil
- Subjects
- *
3-D printers , *ARCHAEOLOGICAL dating , *ARCHAEOLOGICAL excavations , *REVERSE engineering , *THREE-dimensional printing , *DIGITAL images - Abstract
Classification, description and interpretation methods of the ceramic vessels as well as the products made of metal, glass etc. unearthed during the archaeological excavations are very important tools for dating archaeological sites. In this study, from the finds uncovered during the archaeological excavations of Beçin Castle, which have been carried out until today a group of artifacts found in the years 2018-2019 was examined. The three-dimensional digital images of ceramic, metal, glass artifacts selected for inspection and inventory were taken in computer environment by using 3D scanner and their drawings were made. Using these systems object is digitized and become ready for CAD design. 3D models serve also as the basis of the three-dimensional objects to be produced and are converted to solid objects by 3D printers. Solid modeling represents the actual volume and the appearance of the object to be modeled. On the other hand, in surface modeling volume is not modeled. Only the shell of the physical object is modeled to represent the boundaries. This type of models is created more easily but doesn’t completely suffice for production in comparison to solid modeling. By means of documentation of archaeological findings using above mentioned 3D scanner and completing/reproducing them using 3D printers, potential mechanical and chemical damages which may occur in the unique artifacts during the performance of the studies such as drawing etc. can be avoided. After finishing the documentation studies of artifacts obtained from the Excavation in Beçin Castle with this method, 3D printing and completion/reproduction trials were performed in selected groups. This study based on the non-contact 3D scanning method through digitization and reconstruction of the objects in original scales with a sensitivity of ≥ 0,05 mm showed that this method makes a significant and indisputable contribution to documentation, protection, preservation of the especially unique objects obtained in the excavation and passing down the artifacts and their information to future generations accurately. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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43. Three-Dimensional Immersion Scanning Technique: A Scalable Low-Cost Solution for 3D Scanning Using Water-Based Fluid.
- Author
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Gonçalves, Ricardo Spyrides Boabaid Pimentel and Haueisen, Jens
- Subjects
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OPTICAL scanners , *XANTHAN gum , *FLUIDS , *SIGNAL-to-noise ratio , *SCANNING systems , *RADON transforms , *STEPPING motors - Abstract
Three-dimensional scanning technology has been traditionally used in the medical and engineering industries, but these scanners can be expensive or limited in their capabilities. This research aimed to develop low-cost 3D scanning using rotation and immersion in a water-based fluid. This technique uses a reconstruction approach similar to CT scanners but with significantly less instrumentation and cost than traditional CT scanners or other optical scanning techniques. The setup consisted of a container filled with a mixture of water and Xanthan gum. The object to be scanned was submerged at various rotation angles. A stepper motor slide with a needle was used to measure the fluid level increment as the object being scanned was submerged into the container. The results showed that the 3D scanning using immersion in a water-based fluid was feasible and could be adapted to a wide range of object sizes. The technique produced reconstructed images of objects with gaps or irregularly shaped openings in a low-cost fashion. A 3D printed model with a width of 30.7200 ± 0.2388 mm and height of 31.6800 ± 0.3445 mm was compared to its scan to evaluate the precision of the technique. Its width/height ratio (0.9697 ± 0.0084) overlaps the margin of error of the width/height ratio of the reconstructed image (0.9649 ± 0.0191), showing statistical similarities. The signal-to-noise ratio was calculated at around 6 dB. Suggestions for future work are made to improve the parameters of this promising, low-cost technique. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
44. Effect of Temperature, Holding Time, and Addition of Sn on Density on Metal Injection Molding Sintering Process.
- Author
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Jannah, Wardatul, Yudistiro, Danang, Asrofi, Mochamad, Darsin, Mahros, and Maulana, Ahmad Rendi
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TEMPERATURE effect , *TIN , *INJECTION molding , *METALWORK , *SINTERING , *TAGUCHI methods , *POWDER metallurgy , *INJECTION molding of metals - Abstract
Metal injection molding (MIM) is a metal forming technique that combines powder metallurgy with plastic injection molding. MIM is very efficient in manufacturing small and complex products in large quantities. The MIM process has four steps: mixing, debinding, injection molding, and sintering. This research was conducted to determine the effect of variations in Sn addition, temperature, and holding time on the density of Al-PP products after the sintering process. Density is mass per volume so to find out the volume of Al-PP products, the use of a 3D scanner was attempted along with the EinScan application and a mesh mixer. The Taguchi method was used for data processing to determine the influence of variations in Sn addition, temperature, and holding time on density. The calculation of the percentage contribution showed that variations in Sn addition, temperature, and holding time affected density by 47%, 21%, and 3%. Also, 2% Sn addition yielded a reasonably good microstructure formation compared to without Sn addition and 1% Sn addition, where many voids remained in the specimen (the more significant the voids, the lower the density). [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
45. THREE-DIMENSIONAL RECONSTRUCTION AND EVALUATION OF DECUBITUS USING A 3D SCANNER.
- Author
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Molnár-Zékány, Szabina and Árvai-Homolya, Szilvia
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PATIENT care ,INFORMATION technology ,NURSES ,ULCERS ,PHYSICIANS - Abstract
The aim of this study is to improve the field of patient care in medicine by utilizing information technology, as well as to help, assist nurses and doctors in their work and accelerate patients' recovery. In the case of long-term, mostly elderly patients, a condition known as chronic pressure ulcer, decubitus, or pressure sore may develop. Treating these decubitus ulcers takes time and patience. In order to find the appropriate treatment, it can be helpful to gather as much data as possible about the wound and categorize the severity type based on these collected data. This problem will be addressed and explored using the potential of artificial intelligence and three-dimensional digitisation. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
46. A simple anthropometric estimation formula for healthy female labourers' leg volume.
- Author
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Tu, Hsin-Hung
- Subjects
- *
EXERCISE physiology , *FEMALES , *SCANNING systems - Abstract
Leg volume (LV) is an important reference in nutrition, physiology in exercise, or clinical diagnosis. Therefore, how to evaluate LV easily and quickly with accuracy is important in these areas. To develop a simple anthropometric estimation formula with ease of use and good accuracy for leg volume (LV) of female labourers. One hundred and thirty female labourers (110 subjects for formula regression procedure and 20 subjects for the comparison phase) were recruited as subjects with no reported leg surgery history, trauma, or deformity. A set of 3 D scanners was used to measure the range data of each subject's leg. The resultant LV estimation formula is LV = 0.215 × LL × CTH1.620 with R2 = 0.967, in which LL stands for leg length and CTH for circumference of thigh. Mean error of this LV estimation is 0.10% and much smaller than that of the previous study (25.11% with significant difference). An anthropometric estimation formula for female labourers' leg volume was developed in this study. Estimation mean error of this formula is much smaller than the one in the previous study. This formula is easy to use and shows good accuracy in estimating female labourers' leg volume. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
47. Diagnosis and Assessment of Dental Caries Using Novel Bioactive Caries Detecting Dye Solution.
- Author
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Govind, Shashirekha, Jena, Amit, Kamilla, Sushanta Kumar, Mohanty, Neeta, Mallikarjuna, Rachappa M., Nalawade, Triveni, Saraf, Sanjay, Khaldi, Naseer Al, Jahdhami, Salma Al, and Shivagange, Vinay
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DENTAL caries ,TOOTH sensitivity ,DENTAL extraction ,FACIAL expression ,MINIMALLY invasive dentistry ,TOOTHACHE - Abstract
Background: The goal of materials should be early caries detection, removal of carious lesions, and reduction of dentin hypersensitivity. Thus, the study aims to determine the efficacy of a bioactive caries detecting dye (BCD) for the diagnosing and mechanical removal of occlusal and proximal dental caries. Methods: Patients with occlusal (A1, A2) and proximal carious lesions (B1, B2) were treated with the rotary technique and BCD solution on 120 teeth (n = 60 for each). Group 1: Excavation was performed using diamond points. Group 2: 0.5 mL of BCD solution was scrubbed for 20 sec and excavation was performed with a sharp spoon excavator. Post-excavation cavity volume analysis was performed using a 3D scanner. The time required, VAS for pain, VAS for facial expression, and sound eye motor scoring were scored during excavation. Post-restoration evaluation was performed at 3, 6, and 12 months (FDI criteria). Results: The chi-square test revealed that the A1 (197.90 30.97 s) and B1 (273.06 69.95 s) had significantly less mean procedural time than the A2 (292.13 44.87 s) and B2 (411.86 88.34 s). BCD (A2, B2) group showed good patient acceptance, less pain during caries excavation VAS (p = 0.001, FACE (p = 0.001), and SEM (p < 0.001) analysis than the rotary group. There was a statistically insignificant difference between groups immediately (p = 0.235), (p = 0.475) and after 24 h (p = 0.561), (p = 0.688). Color score, hardness of excavated surface, and caries removal score for occlusal and proximal groups showed insignificant differences between the groups. BCD group showed significantly less mean caries excavated volume for the occlusal group (p = 0.003) as compared to the proximal group (p = 0.417) evaluated by 3D scanner. Evaluation of restoration after 3-, 6-, and 12 months intervals (Occlusal caries group (p = 0.247), (p = 0.330), and (0.489) and Proximal caries group (p = 0.299), (p = 0.594), and (0.494)) was acceptable for both the groups. Conclusion: BCD helps in identification of dental caries clinically, radiographically, and in effective removal of denatured teeth with less pain or sensitivity. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
48. Beyond water: 3D laser scanning offers a cutting-edge alternative for upper limb volume assessment.
- Author
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Marsocci, Antonio, Santandrea, Sheila, Lanfranchi, Elena, Donati, Danilo, and Tedeschi, Roberto
- Subjects
- *
OPTICAL scanners , *INTRACLASS correlation , *BLAND-Altman plot , *CONFIDENCE intervals , *DISPLACEMENT (Mechanics) - Abstract
The primary aim of this study was to evaluate the reliability and efficiency of a 3D laser scanner as a tool for volumetric measurement of the upper limbs, comparing it with the gold standard method of non-reflux water displacement. The study sought to determine whether the 3D scanner could serve as a reliable and time-efficient alternative in clinical settings, particularly for managing conditions like lymphedema.A total of 30 healthy participants (18 women, 12 men) were recruited, and volumetric measurements were taken using both the 3D scanner and water displacement methods. Inter-rater and intra-rater reliability were calculated using the Intraclass Correlation Coefficient (ICC), and agreement between the methods was assessed using a Bland-Altman plot. The time required for each measurement and data processing were recorded and compared between the two methods.The 3D scanner demonstrated excellent inter-rater (ICC = 0.995) and intra-rater (ICC = 0.991) reliability, surpassing the water displacement method (ICC = 0.973 and 0.968, respectively). The Bland-Altman plot showed good agreement between the two methods, with only two measurements outside the 95% confidence limits. However, the 3D scanner required significantly more time for both measurement and data processing (28.55 seconds and 120 seconds, respectively) compared to water displacement (9.64 seconds).The 3D scanner offers high reliability and precision for upper limb volumetric measurements, potentially improving clinical management of conditions such as lymphedema. Despite longer acquisition times, its accuracy and versatility make it a promising tool for future clinical use, especially in scenarios where precise monitoring is crucial. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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49. The three-dimensional course of cranial development of very preterm infants during the first year of life.
- Author
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Santander, P., Quast, A., Hubbert, J., Meyer-Marcotty, P., Hensel, K.O., Bergmann, C., Schmidt, S., and Dieks, J.K.
- Subjects
- *
PREMATURE infants , *NEURAL development , *INFANTS , *COHORT analysis , *CLINICAL trials - Abstract
Cranial measurements are crucial for evaluating preterm general development because they are a surrogate tool for evaluating brain growth. Usually, they are based on tape-measured head circumference; however, a three-dimensional (3D) approach expands the diagnostic spectrum to the evaluation of cranial volume and shape. Very preterm (vPT) infants face multiple risks and obstacles in their early development. In this study, we analyze the risk for cranial anomalies of vPT compared with term-born (TB) infants during the first year of life. In this single-centre prospective cohort study, 23 vPT and 24 TB healthy infants were assessed. At term equivalent age (TEA) of vPT and time of birth of TB, and 1, 3, 6 and 12 months of postmenstrual age, respectively, a 3D head scan was performed and cephalometrically evaluated regarding cranial growth (head circumference, cranial volume) and shape. Head circumference and cranial volume showed a similar course in vPT and TB. Cranial shape differed significantly between vPT and TB. At TEA, vPT showed longer and narrower heads (dolichocephaly), a difference that disappeared around the 6th month of life. Presence of plagiocephaly was initially similar in vPT and TB, with an increasing difference between both groups with a peak at six months when 34.8 % of the vPT versus none of the TB showed a moderate to severe plagiocephaly (p = 0.004). In vPT, cranial volume significantly correlated with cranial shape, whereas dolichocephaly at TEA had no influence on the further course of plagiocephaly. Cranial development of vPT follows a different course than of TB in terms of cranial shape anomalies, while cranial growth remains unaffected. German Clinical Trials Register number: DRKS00022558. • The preterm cranial growth rate is equivalent to that of full-term born infants during the first year of life • Preterm head shape differs from full-term born infants during the first 6 months of life in terms of head shape anomalies • After the 6th month until the first year of life, the preterm head spontaneously normalizes with an outcome similar to that of full-term born infants in terms of head shape anomalies [ABSTRACT FROM AUTHOR]
- Published
- 2024
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- View/download PDF
50. Evaluation of the Influence of Vestibular Surface Morphology Variability of Maxillary Incisors on Torque: Examination Using 3D Intraoral Scans
- Author
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Michał Wajda, Joanna Lis, Liwia Minch, and Beata Kawala
- Subjects
bonding ,bracket ,3D scanner ,tooth shape ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Proper torque is an important element of orthodontic treatment. There are many factors affecting effective torque expression, e.g., the interplay between an archwire and a bracket, the precision during bracket positioning, and the morphology of the crown vestibular surface (CrVS) of the tooth. Our study focused on the impact of the maxillary incisor CrVS morphology on the torque exerted by the archwire–bracket interplay. Three-dimensional models of 50 patients acquired through the use of an intraoral scanner were used to examine the four maxillary incisors. A total of 200 teeth were examined. The influence of the tooth crown shape on the bracket position and the related torque change was analyzed with Ortho Analyzer software 2015 (3Shape, Copenhagen, Denmark). All calculations were made for full size archwires. Central incisors showed less variability in their vestibular surfaces than lateral incisors. For the central incisors, the mean values of the additional palatal root torque ranged from 0.6° to 1.6°. For the laterals, the mean values ranged from 1.4° of additional vestibular root torque to 3.5° of additional palatal root torque. The results showed essential morphological differentiation of the CrVS of the maxillary incisors. Therefore, when the bracket is positioned, the individual variation in the tooth surface should be considered and evaluated.
- Published
- 2024
- Full Text
- View/download PDF
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