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Rodríguez-Montaño ÓL, Cortés-Rodríguez CJ, Naddeo F, Uva AE, Fiorentino M, Naddeo A, Cappetti N, Gattullo M, Monno G, Boccaccio A. Irregular Load Adapted Scaffold Optimization: A Computational Framework Based on Mechanobiological Criteria. ACS Biomater Sci Eng 2019; 5:5392-5411. [DOI: 10.1021/acsbiomaterials.9b01023] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Óscar L. Rodríguez-Montaño
- Departamento de Ingeniería Mecánica y Mecatrónica, Universidad Nacional de Colombia, Carrera 30 No. 45-03, Bogotá D.C., Colombia
- Dipartimento di Meccanica, Matematica e Management, Politecnico di Bari, Viale Japigia, 182, 70126 Bari, Italy
| | - Carlos Julio Cortés-Rodríguez
- Departamento de Ingeniería Mecánica y Mecatrónica, Universidad Nacional de Colombia, Carrera 30 No. 45-03, Bogotá D.C., Colombia
| | - Francesco Naddeo
- Dipartimento di Ingegneria Industriale, Università di Salerno, via Giovanni Paolo II, 132, 84084 Fisciano, SA, Italy
| | - Antonio E. Uva
- Dipartimento di Meccanica, Matematica e Management, Politecnico di Bari, Viale Japigia, 182, 70126 Bari, Italy
| | - Michele Fiorentino
- Dipartimento di Meccanica, Matematica e Management, Politecnico di Bari, Viale Japigia, 182, 70126 Bari, Italy
| | - Alessandro Naddeo
- Dipartimento di Ingegneria Industriale, Università di Salerno, via Giovanni Paolo II, 132, 84084 Fisciano, SA, Italy
| | - Nicola Cappetti
- Dipartimento di Ingegneria Industriale, Università di Salerno, via Giovanni Paolo II, 132, 84084 Fisciano, SA, Italy
| | - Michele Gattullo
- Dipartimento di Meccanica, Matematica e Management, Politecnico di Bari, Viale Japigia, 182, 70126 Bari, Italy
| | - Giuseppe Monno
- Dipartimento di Meccanica, Matematica e Management, Politecnico di Bari, Viale Japigia, 182, 70126 Bari, Italy
| | - Antonio Boccaccio
- Dipartimento di Meccanica, Matematica e Management, Politecnico di Bari, Viale Japigia, 182, 70126 Bari, Italy
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Cantore S, Crincoli V, Boccaccio A, Uva AE, Fiorentino M, Monno G, Bollero P, Derla C, Fabiano F, Ballini A, Santacroce L. Recent Advances in Endocrine, Metabolic and Immune Disorders: Mesenchymal Stem Cells (MSCs) and Engineered Scaffolds. Endocr Metab Immune Disord Drug Targets 2019; 18:466-469. [PMID: 29692270 DOI: 10.2174/1871530318666180423102905] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Revised: 02/13/2018] [Accepted: 02/19/2018] [Indexed: 11/22/2022]
Abstract
BACKGROUND New sources of stem cells in adult organisms are constantly emerging. Postnatal Mesenchymal Stem Cells (MSCs), are the most promising support to perform an effective regenerative medicine: such cells have the ability to differentiate into several lineages, such as osteoblasts and chondroblasts, providing novel strategies to improve different complex treatments, during bone regeneration. 3D-printed biomaterials can be designed with geometry aimed to induce stem cells to differentiate towards specific lineage. OBJECTIVE The interaction between stem cells easy to isolate and engineered 3D-printed scaffolds can translate the tissue bio-engineering into bone regenerative surgery. For those reasons, to better identify the complexity represented by the activities and responses of MSCs requires the advance of new target therapies which are not current in endocrine, metabolic and immune disorders and yet to be developed. METHOD This topical review briefly focuses on the new approaches of translational medicine with the use of MSCs and scaffolds engineered with the aid of 3D-printing technology, highlights the osteogenic functions and addresses their applications across the breadth of regenerative medicine. RESULTS The application of bone constructs consisting of the engineered scaffold and MSCs as well as the aspects related to the optimal scaffold geometry that favours the best MSCs differentiation and the improvement of concepts as "sensing surface" were also discussed. CONCLUSION Regenerative surgery is largely growing in the field of translational medicine. The use of new sources of MSCs and the improvement of new concepts of bio-engineered scaffolds will certainly be the next step of customized medicine.
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Affiliation(s)
- Stefania Cantore
- Department of Basic Medical Sciences, Neurosciences and Sense Organs, University of Bari "Aldo Moro", Bari, Italy.,City Unity College, Athens, Greece.,BPP University, Faculty of Dentistry, Birmingham, United Kingdom.,Interdisciplinary Department of Medicine, University of Bari "Aldo Moro", Bari, Italy
| | - Vito Crincoli
- Interdisciplinary Department of Medicine, University of Bari "Aldo Moro", Bari, Italy
| | - Antonio Boccaccio
- Department of Mechanics, Mathematics and Management, Politecnico of Bari, Bari, Italy
| | - Antonio E Uva
- Department of Mechanics, Mathematics and Management, Politecnico of Bari, Bari, Italy
| | - Michele Fiorentino
- Department of Mechanics, Mathematics and Management, Politecnico of Bari, Bari, Italy
| | - Giuseppe Monno
- Department of Mechanics, Mathematics and Management, Politecnico of Bari, Bari, Italy
| | - Patrizio Bollero
- Department of Systems Medicine, University of Rome "Tor Vergata", Rome, Italy
| | | | - Francesca Fabiano
- Department of Biomedical, Odontostomatological Sciences and of Morphological and Functional Images, University of Messina, Messina, Italy
| | - Andrea Ballini
- Department of Basic Medical Sciences, Neurosciences and Sense Organs, University of Bari "Aldo Moro", Bari, Italy.,City Unity College, Athens, Greece.,BPP University, Faculty of Dentistry, Birmingham, United Kingdom.,World Academy of Growth Factors & Stem Cells in Dentistry- WAGroFSCD
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Boccaccio A, Uva AE, Fiorentino M, Monno G, Ballini A, Desiate A. Optimal Load for Bone Tissue Scaffolds with an Assigned Geometry. Int J Med Sci 2018; 15:16-22. [PMID: 29333083 PMCID: PMC5765735 DOI: 10.7150/ijms.20522] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Accepted: 07/24/2017] [Indexed: 01/21/2023] Open
Abstract
Thanks to the recent advances of three-dimensional printing technologies the design and the fabrication of a large variety of scaffold geometries was made possible. The surgeon has the availability of a wide number of scaffold micro-architectures thus needing adequate guidelines for the choice of the best one to be implanted in a patient-specific anatomic region. We propose a mechanobiology-based optimization algorithm capable of determining, for bone tissue scaffolds with an assigned geometry, the optimal value Lopt of the compression load to which they should be subjected, i.e. the load value for which the formation of the largest amounts of bone is favoured and hence the successful outcome of the scaffold implantation procedure is guaranteed. Scaffolds based on hexahedron unit cells were investigated including pores differently dimensioned and with different shapes such as elliptic or rectangular. The algorithm predicted decreasing values of the optimal load for scaffolds with pores with increasing dimensions. The optimal values predicted for the scaffolds with elliptic pores were found higher than those with rectangular ones. The proposed algorithm can be utilized to properly guide the surgeon in the choice of the best scaffold type/geometry that better satisfies the specific patient requirements.
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Affiliation(s)
- Antonio Boccaccio
- Department of Mechanics, Mathematics and Management, Politecnico di Bari, Bari 70126, Italy
| | - Antonio E Uva
- Department of Mechanics, Mathematics and Management, Politecnico di Bari, Bari 70126, Italy
| | - Michele Fiorentino
- Department of Mechanics, Mathematics and Management, Politecnico di Bari, Bari 70126, Italy
| | - Giuseppe Monno
- Department of Mechanics, Mathematics and Management, Politecnico di Bari, Bari 70126, Italy
| | - Andrea Ballini
- Department of Base Medical Sciences, Neurosciences and Sense Organs, University of Bari "Aldo Moro", Bari, Italy
| | - Apollonia Desiate
- Interdisciplinary Department of Medicine, Section of Dentistry, School of Medicine, University of Bari "Aldo Moro", Bari, Italy
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Manghisi VM, Uva AE, Fiorentino M, Bevilacqua V, Trotta GF, Monno G. Real time RULA assessment using Kinect v2 sensor. Appl Ergon 2017; 65:481-491. [PMID: 28283174 DOI: 10.1016/j.apergo.2017.02.015] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Revised: 12/16/2016] [Accepted: 02/22/2017] [Indexed: 05/27/2023]
Abstract
The evaluation of the exposure to risk factors in workplaces and their subsequent redesign represent one of the practices to lessen the frequency of work-related musculoskeletal disorders. In this paper we present K2RULA, a semi-automatic RULA evaluation software based on the Microsoft Kinect v2 depth camera, aimed at detecting awkward postures in real time, but also in off-line analysis. We validated our tool with two experiments. In the first one, we compared the K2RULA grand-scores with those obtained with a reference optical motion capture system and we found a statistical perfect match according to the Landis and Koch scale (proportion agreement index = 0.97, k = 0.87). In the second experiment, we evaluated the agreement of the grand-scores returned by the proposed application with those obtained by a RULA expert rater, finding again a statistical perfect match (proportion agreement index = 0.96, k = 0.84), whereas a commercial software based on Kinect v1 sensor showed a lower agreement (proportion agreement index = 0.82, k = 0.34).
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Boccaccio A, Uva AE, Papi M, Fiorentino M, De Spirito M, Monno G. Nanoindentation characterisation of human colorectal cancer cells considering cell geometry, surface roughness and hyperelastic constitutive behaviour. Nanotechnology 2017; 28:045703. [PMID: 27981954 DOI: 10.1088/1361-6528/28/4/045703] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Characterisation of the mechanical behaviour of cancer cells is an issue of crucial importance as specific cell mechanical properties have been measured and utilized as possible biomarkers of cancer progression. Atomic force microscopy certainly occupies a prominent place in the field of the mechanical characterisation devices. We developed a hybrid approach to characterise different cell lines (SW620 and SW480) of the human colon carcinoma submitted to nanoindentation measurements. An ad hoc algorithm was written that compares the force-indentation curves experimentally retrieved with those predicted by a finite element model that simulates the nanoindentation process and reproduces the cell geometry and the surface roughness. The algorithm perturbs iteratively the values of the cell mechanical properties implemented in the finite element model until the difference between the experimental and numerical force-indentation curves reaches the minimum value. The occurrence of this indicates that the implemented material properties are very close to the real ones. Different hyperelastic constitutive models, such as Arruda-Boyce, Mooney-Rivlin and Neo-Hookean were utilized to describe the structural behaviour of indented cells. The algorithm was capable of separating, for all the cell lines investigated, the mechanical properties of cell cortex and cytoskeleton. Material properties determined via the algorithm were different with respect to those obtained with the Hertzian contact theory. This demonstrates that factors such as: the cell geometry/anatomy and the hyperelastic constitutive behaviour, which are not contemplated in the Hertz's theory hypotheses, do affect the nanoindentation measurements. The proposed approach represents a powerful tool that, only on the basis of nanoindentation measurements, is capable of characterising material at the subcellular level.
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Affiliation(s)
- Antonio Boccaccio
- Dipartimento di Meccanica, Matematica e Management, Politecnico di Bari, Bari, I-70126, Italy
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Corsalini M, Pettini F, Di Venere D, Ballini A, Chiatante G, Lamberti L, Pappalettere C, Fiorentino M, Uva AE, Monno G, Boccaccio A. An Optical System to Monitor the Displacement Field of Glass-fibre Posts Subjected to Thermal Loading. Open Dent J 2016; 10:610-618. [PMID: 27990186 PMCID: PMC5123133 DOI: 10.2174/1874210601610010610] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Revised: 10/04/2016] [Accepted: 10/17/2016] [Indexed: 11/24/2022] Open
Abstract
Endocanalar posts are necessary to build up and retain coronal restorations but they do not reinforce dental roots. It was observed that the dislodgement of post-retained restorations commonly occurs after several years of function and long-term retention may be influenced by various factors such as temperature changes. Temperature changes, in fact, produce micrometric deformations of post and surrounding tissues/materials that may generate high stress concentrations at the interface thus leading to failure. In this study we present an optical system based on the projection moiré technique that has been utilized to monitor the displacement field of endocanalar glass-fibre posts subjected to temperature changes. Measurements were performed on forty samples and the average displacement values registered at the apical and middle region were determined for six different temperature levels. A total of 480 displacement measurements was hence performed. The values of the standard deviation computed for each of the tested temperatures over the forty samples appear reasonably small which proves the robustness and the reliability of the proposed optical technique. The possible implications for the use of the system in the applicative context were discussed.
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Affiliation(s)
- Massimo Corsalini
- Interdisciplinary Department of Medicine, University of Bari Aldo Moro, 70124 Bari, Italy
| | - Francesco Pettini
- Interdisciplinary Department of Medicine, University of Bari Aldo Moro, 70124 Bari, Italy
| | - Daniela Di Venere
- Interdisciplinary Department of Medicine, University of Bari Aldo Moro, 70124 Bari, Italy
| | - Andrea Ballini
- Department of Basic Medical Sciences, Neurosciences and Sensory Organs, University of Bari Aldo Moro, 70124 Bari, Italy
| | - Giuseppe Chiatante
- School of Dentistry, University of Chieti "G. d'Annunzio", 66100 Chieti, Italy
| | - Luciano Lamberti
- Department of Mechanics, Mathematics and Management, Politecnico di Bari, 70126 Bari, Italy
| | - Carmine Pappalettere
- Department of Mechanics, Mathematics and Management, Politecnico di Bari, 70126 Bari, Italy
| | - Michele Fiorentino
- Department of Mechanics, Mathematics and Management, Politecnico di Bari, 70126 Bari, Italy
| | - Antonio E Uva
- Department of Mechanics, Mathematics and Management, Politecnico di Bari, 70126 Bari, Italy
| | - Giuseppe Monno
- Department of Mechanics, Mathematics and Management, Politecnico di Bari, 70126 Bari, Italy
| | - Antonio Boccaccio
- Department of Mechanics, Mathematics and Management, Politecnico di Bari, 70126 Bari, Italy
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Boccaccio A, Uva AE, Fiorentino M, Lamberti L, Monno G. A Mechanobiology-based Algorithm to Optimize the Microstructure Geometry of Bone Tissue Scaffolds. Int J Biol Sci 2016; 12:1-17. [PMID: 26722213 PMCID: PMC4679394 DOI: 10.7150/ijbs.13158] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Accepted: 09/23/2015] [Indexed: 01/02/2023] Open
Abstract
Complexity of scaffold geometries and biological mechanisms involved in the bone generation process make the design of scaffolds a quite challenging task. The most common approaches utilized in bone tissue engineering require costly protocols and time-consuming experiments. In this study we present an algorithm that, combining parametric finite element models of scaffolds with numerical optimization methods and a computational mechano-regulation model, is able to predict the optimal scaffold microstructure. The scaffold geometrical parameters are perturbed until the best geometry that allows the largest amounts of bone to be generated, is reached. We study the effects of the following factors: (1) the shape of the pores; (2) their spatial distribution; (3) the number of pores per unit area. The optimal dimensions of the pores have been determined for different values of scaffold Young's modulus and compression loading acting on the scaffold upper surface. Pores with rectangular section were predicted to lead to the formation of larger amounts of bone compared to square section pores; similarly, elliptic pores were predicted to allow the generation of greater amounts of bone compared to circular pores. The number of pores per unit area appears to have rather negligible effects on the bone regeneration process. Finally, the algorithm predicts that for increasing loads, increasing values of the scaffold Young's modulus are preferable. The results shown in the article represent a proof-of-principle demonstration of the possibility to optimize the scaffold microstructure geometry based on mechanobiological criteria.
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Affiliation(s)
- Antonio Boccaccio
- Dipartimento di Meccanica, Matematica e Management, Politecnico di Bari, 70126 Bari, Italy
| | - Antonio Emmanuele Uva
- Dipartimento di Meccanica, Matematica e Management, Politecnico di Bari, 70126 Bari, Italy
| | - Michele Fiorentino
- Dipartimento di Meccanica, Matematica e Management, Politecnico di Bari, 70126 Bari, Italy
| | - Luciano Lamberti
- Dipartimento di Meccanica, Matematica e Management, Politecnico di Bari, 70126 Bari, Italy
| | - Giuseppe Monno
- Dipartimento di Meccanica, Matematica e Management, Politecnico di Bari, 70126 Bari, Italy
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Pettini F, Corsalini M, Savino MG, Stefanachi G, Di Venere D, Pappalettere C, Monno G, Boccaccio A. Roughness Analysis on Composite Materials (Microfilled, Nanofilled and Silorane) After Different Finishing and Polishing Procedures. Open Dent J 2015; 9:357-67. [PMID: 26734113 PMCID: PMC4645933 DOI: 10.2174/1874210601509010357] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2014] [Revised: 08/17/2015] [Accepted: 08/25/2015] [Indexed: 11/23/2022] Open
Abstract
The finishing and polishing of composite materials affect the restoration lifespan. The market shows a variety
of finishing and polishing procedures and the choice among them is conditioned by different factors such as the resulting
surface roughness. In the present study, 156 samples were realized with three composite materials, -microfilled, nanofilled
and silorane-, and treated with different finishing and polishing procedures. Profilometric analyses were carried out on the
samples’ surface, the measured roughness values were submitted to statistical analysis. A complete factorial plan was
drawn up and two-way analysis of variance (ANOVA) was carried out to investigate whether the following factors affect
the values of roughness: (i) material; (ii) polishing/finishing procedure. Tukey post-hoc test was also conducted to evaluate
any statistically significant differences between the material/procedure combinations. The results show that the tested
materials do not affect the resulting surface quality but roughness values depend on the finishing/polishing procedure
adopted. The procedures that involve: (a) the finishing with medium Sof-Lex discs and (b) the finishing with two tungsten
carbide multi-blade milling cutters Q series and UF series are those that allow the lowest values of roughness to be obtained.
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Affiliation(s)
- Francesco Pettini
- Dental School - University of Bari, Piazza Giulio Cesare 11 - 70125, Bari, Italy
| | - Massimo Corsalini
- Dental School - University of Bari, Piazza Giulio Cesare 11 - 70125, Bari, Italy
| | - Maria Grazia Savino
- Dental School - University of Bari, Piazza Giulio Cesare 11 - 70125, Bari, Italy
| | - Gianluca Stefanachi
- Dental School - University of Bari, Piazza Giulio Cesare 11 - 70125, Bari, Italy
| | - Daniela Di Venere
- Dental School - University of Bari, Piazza Giulio Cesare 11 - 70125, Bari, Italy
| | - Carmine Pappalettere
- Dental School - University of Bari, Piazza Giulio Cesare 11 - 70125, Bari, Italy
| | - Giuseppe Monno
- Dental School - University of Bari, Piazza Giulio Cesare 11 - 70125, Bari, Italy
| | - Antonio Boccaccio
- Dental School - University of Bari, Piazza Giulio Cesare 11 - 70125, Bari, Italy
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Gattullo M, Uva AE, Fiorentino M, Monno G. Effect of Text Outline and Contrast Polarity on AR Text Readability in Industrial Lighting. IEEE Trans Vis Comput Graph 2015; 21:638-651. [PMID: 26357210 DOI: 10.1109/tvcg.2014.2385056] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Text readability with augmented reality head-worn displays is critical and at present time, there are no standard guidelines to follow. The readability depends mainly on background lighting, display technology (i.e., OST: optical see-through or VST: video see-through), and text style (e.g., plain text, outline or billboard). In this work, we addressed the readability limits for industrial activities. We experimented the effects of two background illuminances levels (1,000 lx for very fine basic industrial tasks and 4,000 lx for fine machining), two commercially available head-worn display technologies, variable outline widths and contrast polarity of text. We analyzed the performance of 12 subjects by collecting about 3,400 measurements using a specific test application and followed by qualitative interviews. With high illuminances, VST performed better than OST, regardless of contrast polarity and outline width. We found that negative contrast polarity is preferable with VST, and that just a minimum outline (1 px) around black text is optimal. On the contrary, positive contrast polarity should be used with OST and outline is not effective. Therefore, we evaluated the usage limits of the OST by sampling its contrast sensitivity function.
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Debernardis S, Fiorentino M, Gattullo M, Monno G, Uva AE. Text readability in head-worn displays: color and style optimization in video versus optical see-through devices. IEEE Trans Vis Comput Graph 2014; 20:125-139. [PMID: 24201331 DOI: 10.1109/tvcg.2013.86] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Efficient text visualization in head-worn augmented reality (AR) displays is critical because it is sensitive to display technology, text style and color, ambient illumination and so on. The main problem for the developer is to know the optimal text style for the specific display and for applications where color coding must be strictly followed because it is regulated by laws or internal practices. In this work, we experimented the effects on readability of two head-worn devices (optical and video see-through), two backgrounds (light and dark), five colors (white, black, red, green, and blue), and two text styles (plain text and billboarded text). Font type and size were kept constant. We measured the performance of 15 subjects by collecting about 5,000 measurements using a specific test application and followed by qualitative interviews. Readability turned out to be quicker on the optical see-through device. For the video see-through device, background affects readability only in case of text without billboard. Finally, our tests suggest that a good combination for indoor augmented reality applications, regardless of device and background, could be white text and blue billboard, while a mandatory color should be displayed as billboard with a white text message.
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