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Jurado CA, Afrashtehfar KI, Robles M, Alaqeely RS, Alsayed HD, Lindquist TJ, Alhotan A. Effect of preparation design and endodontic access on fracture resistance of zirconia overlays in mandibular molars: An in vitro study. J Prosthodont 2024. [PMID: 38734932 DOI: 10.1111/jopr.13865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2023] [Accepted: 04/17/2024] [Indexed: 05/13/2024] Open
Abstract
PURPOSE To evaluate the fracture resistance of zirconia overlays, considering various preparation designs and the presence of endodontic access. MATERIALS AND METHODS Ninety translucent zirconia (5Y-PSZ) overlay restorations were divided into six groups (n = 15/group) based on different preparation designs, with and without endodontic access: chamfer margin 4 mm above the gingival level without (group 1) and with endodontic access (group 2); margin 2 mm above the gingival level without (group 3) and with endodontic access (group 4); overlay with no chamfer margin without (group 5) and with endodontic access (group 6). Restorations were bonded to mandibular first molar resin dies, and the groups with endodontic access were sealed with flowable resin composite. All restorations underwent 100,000 cycles of thermal cycling between 5°C and 55°C, followed by loading until fracture. Maximum load and fracture resistance were recorded. ANOVA with Tukey post-hoc tests were used for statistical comparison (α < 0.05). RESULTS Fracture resistance significantly varied among overlay designs with and without endodontic access (p < 0.001), except for the no-margin overlays (groups 5 and 6). Overlays with a 2 mm margin above the gingival margin with endodontic access (group 4) exhibited significantly higher fracture resistance compared to both the 4-mm supragingival (group 2) and no-margin (group 6) designs, even when compared to their respective intact groups (groups 1 and 5). There were no significant differences between the no-margin and 4-mm supragingival overlays. CONCLUSION The more extensive zirconia overlay for mandibular molars is the first choice since the 2 mm margin above the gingival level design withstood considerable loads even after undergoing endodontic access. A no-margin overlay is preferred over the 4-mm supragingival design as it preserves more tooth structure and there was no outcome difference, irrespective of endodontic access. Caution is warranted in interpreting these findings due to the in vitro nature of the study.
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Affiliation(s)
- Carlos A Jurado
- Operative Dentistry Division, Department of General Dentistry, University of Tennessee Health Science Center College of Dentistry, Memphis, Tennessee, USA
| | - Kelvin I Afrashtehfar
- Department of Reconstructive Dentistry and Gerodontology (RekGero), School of Dental Medicine, University of Bern, Bern, Switzerland
- Evidence-Based Practice Unit (EBPU), Clinical Sciences Department, College of Dentistry, Ajman University, Ajman City, UAE
- Prosthodontics Private Practice, Dental Clinics, Abu Dhabi, UAE
- Artificial Intelligence Research Center (AIRC), Ajman University, Dubai, UAE
| | - Manuel Robles
- Department of Restorative Dentistry, Universidad del Valle De Mexico, Hermosillo, Sonora, Mexico
| | - Razan S Alaqeely
- Department of Periodontics, College of Dentistry, King Saud University, Riyadh, Saudi Arabia
| | - Hussain D Alsayed
- Department of Prosthetic Dental Sciences, College of Dentistry, King Saudi University, Riyadh, Saudi Arabia
| | - Terry J Lindquist
- Department of Prosthodontics, The University of Iowa College of Dentistry and Dental Clinics, Iowa City, Iowa, USA
| | - Abdulaziz Alhotan
- Dental Health Department, College of Applied Medical Sciences, King Saud University, Riyadh, Saudi Arabia
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Brown T, Kee E, Xu X, Chapple A, Stamitoles C, Armbruster P, Ballard RW. Shear bond strength of orthodontic brackets bonded to high-translucent dental zirconia with different surface treatments: An in vitro study. Int Orthod 2024; 22:100822. [PMID: 37992472 DOI: 10.1016/j.ortho.2023.100822] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Revised: 10/09/2023] [Accepted: 10/18/2023] [Indexed: 11/24/2023]
Abstract
PURPOSE The objective of this study was to compare the shear bond strengths of orthodontic brackets bonded to translucent dental zirconia samples which are anatomically accurate and treated with various surface treatments. METHODS This in vitro study included 156 samples from 3 brands of high-translucent zirconia split into a control group and 4 surface treatment groups: 9.6% hydrofluoric acid etching, 50-micron aluminium oxide particle air abrasion, and 30-micron tribochemical silica coating (TBS) particle air abrasion with and without silane application. After surface treatment, all groups were primed with a 10-MDP primer and bonded to metal orthodontic brackets. Shear bond strength (SBS) was tested and results were compared between all groups. Data analysis consisted of a balanced two-factor factorial ANOVA, a Shapiro-Wilks test, and a non-parametric permutation test. The significance level was set at 0.05. RESULTS Among all surface treatments, aluminium oxide particle abrasion produced significantly higher SBS (P≤0.002). Lava™ Plus zirconia samples had significantly higher SBS than Cercon® samples (P<0.0001). TBS surface treatment produced significantly higher SBS on Lava™ Plus samples than it did on the other zirconia brands (P=0.032). CONCLUSIONS This study indicated that mechanical abrasion using aluminium oxide in combination with a 10-MDP primer creates a higher SBS to high-translucent zirconia than the bond created by tribochemical silica coating. Also, there was no significant difference in ARI regardless of zirconia brand or surface preparation.
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Affiliation(s)
- Thomas Brown
- Department of Orthodontics, School of Dentistry, LSU Health-New Orleans, 1100 Florida Avenue, New Orleans, LA 70119, USA
| | - Edwin Kee
- Department of Prosthodontics, School of Dentistry, LSU Health-New Orleans, 1100 Florida Avenue, New Orleans, LA 70119, USA
| | - Xiaoming Xu
- Department of Oral and Craniofacial Biology, School of Dentistry, LSU Health-New Orleans, 1100 Florida Avenue, New Orleans, LA 70119, USA
| | - Andrew Chapple
- Department of Interdisciplinary Oncology, School of Medicine, LSU Health Sciences Center, 733 Bolivar St, New Orleans, LA 70112, USA
| | - Charles Stamitoles
- School of Dentistry, LSU Health-New Orleans, 1100 Florida Avenue, New Orleans, LA 70119, USA
| | - Paul Armbruster
- Department of Orthodontics, School of Dentistry, LSU Health-New Orleans, 1100 Florida Avenue, New Orleans, LA 70119, USA
| | - Richard W Ballard
- Department of Orthodontics, School of Dentistry, LSU Health-New Orleans, 1100 Florida Avenue, New Orleans, LA 70119, USA.
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Hoffmann M, Mayinger F, Stawarczyk B. Influence of different surface finishing procedures of strength-gradient multilayered zirconia crowns on two-body wear and fracture load: Lithium silicate or leucite glazing versus polishing? J Mech Behav Biomed Mater 2024; 150:106307. [PMID: 38071838 DOI: 10.1016/j.jmbbm.2023.106307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2023] [Revised: 11/29/2023] [Accepted: 12/03/2023] [Indexed: 01/09/2024]
Abstract
OBJECTIVES To examine the influence of different finishing procedures on the surface roughness, wear resistance and fracture load of strength-gradient multilayered zirconia. MATERIALS AND METHODS Zirconia crowns (Multilayer 3D pro; n = 96) were manufactured and treated with a lithium-silicate- (LISI_S), leucite-based glaze spray (LEU_S), leucite-based glaze mass (LEU_M) or polished (POL). Natural molars (CG; n = 24) acted as a control. Roughness was determined on flat glazed specimens (n = 28). Two-body wear was examined by digitalizing and matching the occlusal surface before and after thermo-mechanical aging (6,000 thermal and 1,200,000 chewing cycles). The groups were split to measure fracture load initially and after aging. Kolmogorov-Smirnov, Spearman correlation, Kruskal-Wallis-H, Levene's test, one-way ANOVA with Scheffé post-hoc and Weibull modulus were computed. RESULTS POL presented the lowest and LEU_S the highest roughness. Following POL, no ceramic loss was observed. LISI_S, LEU_S and LEU_M showed lower ceramic wear than the CG. The lowest wear of the antagonist was observed for the CG. LISI_S showed a lower antagonistic wear than LEU_S, LEU_M and POL. LISI_S, LEU_S, LEU_M and POL showed higher fracture load values and Weibull moduli than the CG. Artificial aging did not impact the fracture load or Weibull moduli. SIGNIFICANCE With glazed groups showing height losses closer to the CG, glazing should be preferred to polishing when approximating the wear behavior of a natural dentition. Finishing of monolithic zirconia by glazing with a lithium silicate-based spray is recommended to preserve the antagonists. All examined zirconia crowns presented sufficient mechanical properties to withstand masticatory forces, even after prolonged aging.
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Affiliation(s)
- Moritz Hoffmann
- Department of Prosthetic Dentistry, Dental School, University Hospital, LMU Munich, Goethestraße 70, 80336, Munich, Germany.
| | - Felicitas Mayinger
- Department of Prosthetic Dentistry, Dental School, University Hospital, LMU Munich, Goethestraße 70, 80336, Munich, Germany
| | - Bogna Stawarczyk
- Department of Prosthetic Dentistry, Dental School, University Hospital, LMU Munich, Goethestraße 70, 80336, Munich, Germany
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Benalcázar-Jalkh EB, Bergamo ETP, Campos TMB, Coelho PG, Sailer I, Yamaguchi S, Alves LMM, Witek L, Tebcherani SM, Bonfante EA. A Narrative Review on Polycrystalline Ceramics for Dental Applications and Proposed Update of a Classification System. MATERIALS (BASEL, SWITZERLAND) 2023; 16:7541. [PMID: 38138684 PMCID: PMC10744432 DOI: 10.3390/ma16247541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 11/07/2023] [Accepted: 11/25/2023] [Indexed: 12/24/2023]
Abstract
Dental zirconias have been broadly utilized in dentistry due to their high mechanical properties and biocompatibility. Although initially introduced in dentistry as an infrastructure material, the high rate of technical complications related to veneered porcelain has led to significant efforts to improve the optical properties of dental zirconias, allowing for its monolithic indication. Modifications in the composition, processing methods/parameters, and the increase in the yttrium content and cubic phase have been presented as viable options to improve zirconias' translucency. However, concerns regarding the hydrothermal stability of partially stabilized zirconia and the trade-off observed between optical and mechanical properties resulting from the increased cubic content remain issues of concern. While the significant developments in polycrystalline ceramics have led to a wide diversity of zirconia materials with different compositions, properties, and clinical indications, the implementation of strong, esthetic, and sufficiently stable materials for long-span fixed dental prostheses has not been completely achieved. Alternatives, including advanced polycrystalline composites, functionally graded structures, and nanosized zirconia, have been proposed as promising pathways to obtain high-strength, hydrothermally stable biomaterials. Considering the evolution of zirconia ceramics in dentistry, this manuscript aims to present a critical perspective as well as an update to previous classifications of dental restorative ceramics, focusing on polycrystalline ceramics, their properties, indications, and performance.
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Affiliation(s)
- Ernesto B. Benalcázar-Jalkh
- Department of Prosthodontics and Periodontology, Bauru School of Dentistry, University of São Paulo, Bauru 17012-901, SP, Brazil
| | - Edmara T. P. Bergamo
- Department of Prosthodontics and Periodontology, Bauru School of Dentistry, University of São Paulo, Bauru 17012-901, SP, Brazil
- Biomaterials Division, NYU Dentistry, New York, NY 10010, USA
- Department of Prosthodontics, NYU Dentistry, New York, NY 10010, USA
| | - Tiago M. B. Campos
- Department of Prosthodontics and Periodontology, Bauru School of Dentistry, University of São Paulo, Bauru 17012-901, SP, Brazil
| | - Paulo G. Coelho
- DeWitt Daughtry Family Department of Surgery, Division of Plastic Surgery, Miller School of Medicine, University of Miami, Miami, FL 33136, USA
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL 33136, USA
| | - Irena Sailer
- Division of Fixed Prosthodontics and Biomaterials, University Clinics of Dental Medicine, University of Geneva, 1211 Geneva, Switzerland
| | - Satoshi Yamaguchi
- Department of Dental Biomaterials, Osaka University Graduate School of Dentistry, Suita 565-0871, Osaka, Japan;
| | - Larissa M. M. Alves
- Department of Prosthodontics and Periodontology, Bauru School of Dentistry, University of São Paulo, Bauru 17012-901, SP, Brazil
| | - Lukasz Witek
- Biomaterials Division, NYU Dentistry, New York, NY 10010, USA
- Department of Biomedical Engineering, NYU Tandon School of Engineering, New York University, Brooklyn, NY 11201, USA
- Hansjörg Wyss Department of Plastic Surgery, NYU Grossman School of Medicine, New York, NY 10017, USA
| | - Sérgio M. Tebcherani
- Department of Production Engineering, Federal University of Technology—Paraná, Av. Monteiro Lobato Km 04, Ponta Grossa 84016-210, PR, Brazil;
| | - Estevam A. Bonfante
- Department of Prosthodontics and Periodontology, Bauru School of Dentistry, University of São Paulo, Bauru 17012-901, SP, Brazil
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Mijiritsky E, Elad A, Krausz R, Ivanova V, Zlatev S. Clinical performance of full-arch implant-supported fixed restorations made of monolithic zirconia luted to a titanium bar: A retrospective study with a mean follow-up of 16 months. J Dent 2023; 137:104675. [PMID: 37607658 DOI: 10.1016/j.jdent.2023.104675] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 08/17/2023] [Accepted: 08/19/2023] [Indexed: 08/24/2023] Open
Abstract
OBJECTIVES This retrospective case series aimed to evaluate the short-term clinical advantages and limitations of full-arch implant-supported restorations made of monolithic zirconia suprastructures passively luted to titanium bar infrastructures and to report the rate of complications within a minimum of 1-year follow-up. MATERIALS AND METHODS This study included 31 patients (19 men and 12 women) requiring full-arch implant-supported prostheses in the upper or lower jaw. The patients were treated using an entirely digital approach from implant planning and guided implant placement to prosthetic construction planning, design, and fabrication. Full-arch implant-supported monolithic zirconia suprastructures luted to prism-shaped titanium bars were used in all the cases. All the restorations were evaluated for biological and technical complications during fixed control appointments. RESULTS No implant failures or serviceable prosthetic complications were reported, and the prosthetic survival rate was 100%, with a follow-up duration ranging from 12 months to 20 months. In two cases, a fracture line was observed in the zirconia suprastructures, although it did not require any intervention. CONCLUSIONS After a 16-month mean follow-up period, the monolithic zirconia implant-supported full-arch fixed dental prostheses demonstrated no biological or technical complications. Further clinical studies with long-term results are required to confirm these reported outcomes. CLINICAL SIGNIFICANCE CAD-/CAM-milled monolithic zirconia structures passively luted to titanium bar infrastructures are a viable treatment option for full-arch restorations over implants, demonstrating 100% survival and success rates in the present study. The outcomes of this short-term retrospective study indicated high success in function, aesthetics, phonetics, and the ability to maintain flawless hygiene. However, the long-term results of restorations produced using the proposed technique should be considered before recommending this approach for routine clinical use.
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Affiliation(s)
- Eitan Mijiritsky
- Department of Head and Neck and Maxillofacial Surgery, Tel-Aviv Sourasky Medical Center, The Faculty of Medicine, Tel-Aviv University, Tel Aviv 6139001, Israel
| | | | | | - Vasilena Ivanova
- Oral Surgery Department, Faculty of Dental Medicine, Medical University of Plovdiv, Plovdiv 4000, Bulgaria.
| | - Stefan Zlatev
- CAD/CAM Center of Dental Medicine at the Research Institute, Medical University-Plovdiv, Plovdiv 4000, Bulgaria
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Turkyilmaz I. Maxillary rehabilitation of tetracycline-stained teeth with diastemas by using ceramic veneers and a digital workflow. J Dent Sci 2023; 18:1425-1426. [PMID: 37404610 PMCID: PMC10316506 DOI: 10.1016/j.jds.2023.04.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 04/19/2023] [Indexed: 07/06/2023] Open
Affiliation(s)
- Ilser Turkyilmaz
- Corresponding author. New York University College of Dentistry, Department of Prosthodontics, 380 Second Avenue, Suite 302, New York, NY, 10010, USA.
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Worpenberg C, Stiesch M, Eisenburger M, Breidenstein B, Busemann S, Greuling A. The effect of surface treatments on the adhesive bond in all-ceramic dental crowns using four-point bending and dynamic loading tests. J Mech Behav Biomed Mater 2023; 139:105686. [PMID: 36706651 DOI: 10.1016/j.jmbbm.2023.105686] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 01/10/2023] [Accepted: 01/23/2023] [Indexed: 01/26/2023]
Abstract
The aim of this study was to determine the effect of sandblasting, grinding and plasma treatment on the adhesive bond strength between framework ceramic (Y-TZP) and veneering ceramic (feldspar ceramic). Therefore, four-point bending specimens (n = 180) were cut from densely sintered 3Y-TZP blanks. Subsequently, 80 of these samples received surface treatment by sandblasting and 80 samples by grinding. A reference group (20 samples) was not processed. Half of the specimens that received a surface treatment were additionally exposed to an oxygen plasma treatment. After processing, all specimens were manually veneered with feldspar ceramic and examined with a four-point bending test to evaluate the strain energy release rate G. The surface treatment parameters that achieved the highest and lowest G were transferred to real geometries of a posterior crown (n = 45). The crowns' ceramic framework was sandblasted and veneered by hand. The all-ceramic crowns were tested in a dynamic loading test and Wöhler curves were evaluated. Four-point bending samples blasted at an angle of 90° at 6 bar and a working distance of 1.5 cm without plasma treatment achieved the highest energy release rate. Samples blasted at an angle of 90° at 2 bar and a working distance of 1 cm with plasma treatment achieved the lowest energy release rate. Overall, plasma treatment did not improve bond strength. In the dynamic loading test, the group blasted with 2 bar showed the best results.
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Affiliation(s)
- Christin Worpenberg
- Department of Prosthetic Dentistry and Biomedical Materials Science, Hannover Medical School, Carl-Neuberg-Straße 1, 30625, Hannover, Germany
| | - Meike Stiesch
- Department of Prosthetic Dentistry and Biomedical Materials Science, Hannover Medical School, Carl-Neuberg-Straße 1, 30625, Hannover, Germany
| | - Michael Eisenburger
- Department of Prosthetic Dentistry and Biomedical Materials Science, Hannover Medical School, Carl-Neuberg-Straße 1, 30625, Hannover, Germany
| | - Bernd Breidenstein
- Institute of Production Engineering and Machine Tools, Leibniz University Hannover, An der Universität 2, 30823, Garbsen, Germany
| | - Sarah Busemann
- Institute of Production Engineering and Machine Tools, Leibniz University Hannover, An der Universität 2, 30823, Garbsen, Germany
| | - Andreas Greuling
- Department of Prosthetic Dentistry and Biomedical Materials Science, Hannover Medical School, Carl-Neuberg-Straße 1, 30625, Hannover, Germany.
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Fidalgo-Pereira R, Torres O, Carvalho Ó, Silva FS, Catarino SO, Özcan M, Souza JCM. A Scoping Review on the Polymerization of Resin-Matrix Cements Used in Restorative Dentistry. MATERIALS (BASEL, SWITZERLAND) 2023; 16:1560. [PMID: 36837188 PMCID: PMC9961405 DOI: 10.3390/ma16041560] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 02/08/2023] [Accepted: 02/09/2023] [Indexed: 06/18/2023]
Abstract
In dentistry, clinicians mainly use dual-cured or light-cured resin-matrix cements to achieve a proper polymerization of the organic matrix leading to enhanced physical properties of the cement. However, several parameters can affect the polymerization of resin-matrix cements. The main aim of the present study was to perform a scoping review on the degree of conversion (DC) of the organic matrix, the polymerization, and the light transmittance of different resin-matrix cements used in dentistry. A search was performed on PubMed using a combination of the following key terms: degree of conversion, resin cements, light transmittance, polymerization, light curing, and thickness. Articles in the English language published up to November 2022 were selected. The selected studies' results demonstrated that restorative structures with a thickness higher than 1.5 mm decrease the light irradiance towards the resin-matrix cement. A decrease in light transmission provides a low energy absorption through the resin cement leading to a low DC percentage. On the other hand, the highest DC percentages, ranging between 55 and 75%, have been reported for dual-cured resin-matrix cements, although the polymerization mode and exposure time also influence the DC of monomers. Thus, the polymerization of resin-matrix cements can be optimized taking into account different parameters of light-curing, such as adequate light distance, irradiance, exposure time, equipment, and wavelength. Then, optimum physical properties are achieved that provide a long-term clinical performance of the cemented restorative materials.
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Affiliation(s)
- Rita Fidalgo-Pereira
- University Institute of Health Sciences (IUCS), CESPU, 4585-116 Gandra, Portugal
- Center for Interdisciplinary Research in Health (CIIS), Faculty of Dental Medicine (FMD), Universidade Católica Portuguesa (UCP), 3504-505 Viseu, Portugal
| | - Orlanda Torres
- University Institute of Health Sciences (IUCS), CESPU, 4585-116 Gandra, Portugal
| | - Óscar Carvalho
- Center for MicroElectroMechanical Systems (CMEMS-UMINHO), University of Minho, Campus Azurém, 4800-058 Guimarães, Portugal
- LABBELS Associate Laboratory, University of Minho, 4805-017 Guimarães, Portugal
| | - Filipe S. Silva
- Center for MicroElectroMechanical Systems (CMEMS-UMINHO), University of Minho, Campus Azurém, 4800-058 Guimarães, Portugal
- LABBELS Associate Laboratory, University of Minho, 4805-017 Guimarães, Portugal
| | - Susana O. Catarino
- Center for MicroElectroMechanical Systems (CMEMS-UMINHO), University of Minho, Campus Azurém, 4800-058 Guimarães, Portugal
- LABBELS Associate Laboratory, University of Minho, 4805-017 Guimarães, Portugal
| | - Mutlu Özcan
- Division of Dental Biomaterials, Center of Dental Medicine, Clinic of Reconstructive Dentistry, University of Zurich, 8032 Zurich, Switzerland
| | - Júlio C. M. Souza
- University Institute of Health Sciences (IUCS), CESPU, 4585-116 Gandra, Portugal
- Center for MicroElectroMechanical Systems (CMEMS-UMINHO), University of Minho, Campus Azurém, 4800-058 Guimarães, Portugal
- LABBELS Associate Laboratory, University of Minho, 4805-017 Guimarães, Portugal
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