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Umrath F, Schmitt LF, Kliesch SM, Schille C, Geis-Gerstorfer J, Gurewitsch E, Bahrini K, Peters F, Reinert S, Alexander D. Mechanical and Functional Improvement of β-TCP Scaffolds for Use in Bone Tissue Engineering. J Funct Biomater 2023; 14:427. [PMID: 37623671 PMCID: PMC10455746 DOI: 10.3390/jfb14080427] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Revised: 08/08/2023] [Accepted: 08/11/2023] [Indexed: 08/26/2023] Open
Abstract
Autologous bone transplantation is still considered as the gold standard therapeutic option for bone defect repair. The alternative tissue engineering approaches have to combine good hardiness of biomaterials whilst allowing good stem cell functionality. To become more useful for load-bearing applications, mechanical properties of calcium phosphate materials have to be improved. In the present study, we aimed to reduce the brittleness of β-tricalcium phosphate (β-TCP). For this purpose, we used three polymers (PDL-02, -02a, -04) for coatings and compared resulting mechanical and degradation properties as well as their impact on seeded periosteal stem cells. Mechanical properties of coated and uncoated β-TCP scaffolds were analyzed. In addition, degradation kinetics analyses of the polymers employed and of the polymer-coated scaffolds were performed. For bioactivity assessment, the scaffolds were seeded with jaw periosteal cells (JPCs) and cultured under untreated and osteogenic conditions. JPC adhesion/proliferation, gene and protein expression by immunofluorescent staining of embedded scaffolds were analyzed. Raman spectroscopy measurements gave an insight into material properties and cell mineralization. PDL-coated β-TCP scaffolds showed a significantly higher flexural strength in comparison to that of uncoated scaffolds. Degradation kinetics showed considerable differences in pH and electrical conductivity of the three different polymer types, while the core material β-TCP was able to stabilize pH and conductivity. Material differences seemed to have an impact on JPC proliferation and differentiation potential, as reflected by the expression of osteogenic marker genes. A homogenous cell colonialization of coated and uncoated scaffolds was detected. Most interesting from a bone engineer's point of view, the PDL-04 coating enabled detection of cell matrix mineralization by Raman spectroscopy. This was not feasible with uncoated scaffolds, due to intercalating effects of the β-TCP material and the JPC-formed calcium phosphate. In conclusion, the use of PDL-04 coating improved the mechanical properties of the β-TCP scaffold and promoted cell adhesion and osteogenic differentiation, whilst allowing detection of cell mineralization within the ceramic core material.
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Affiliation(s)
- Felix Umrath
- Department of Oral and Maxillofacial Surgery, University Hospital Tübingen, 72076 Tübingen, Germany; (F.U.); (L.-F.S.); (S.R.)
- Department of Orthopedic Surgery, University Hospital Tübingen, 72076 Tübingen, Germany
| | - Lukas-Frank Schmitt
- Department of Oral and Maxillofacial Surgery, University Hospital Tübingen, 72076 Tübingen, Germany; (F.U.); (L.-F.S.); (S.R.)
| | | | - Christine Schille
- Section Medical Materials Science and Technology, University Hospital Tübingen, 72076 Tübingen, Germany; (C.S.); (J.G.-G.)
| | - Jürgen Geis-Gerstorfer
- Section Medical Materials Science and Technology, University Hospital Tübingen, 72076 Tübingen, Germany; (C.S.); (J.G.-G.)
| | | | | | - Fabian Peters
- Curasan AG, 65933 Frankfurt, Germany; (E.G.); (K.B.); (F.P.)
| | - Siegmar Reinert
- Department of Oral and Maxillofacial Surgery, University Hospital Tübingen, 72076 Tübingen, Germany; (F.U.); (L.-F.S.); (S.R.)
| | - Dorothea Alexander
- Department of Oral and Maxillofacial Surgery, University Hospital Tübingen, 72076 Tübingen, Germany; (F.U.); (L.-F.S.); (S.R.)
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Salewski C, Spintzyk S, von Steuben T, Sandoval Boburg R, Nemeth A, Schille C, Acharya M, Geis-Gerstorfer J, Wendel HP, Popov AF, Schlensak C. ECMO implantation training: Needle penetration in 3D printable materials and porcine aorta. Perfusion 2020; 36:798-802. [PMID: 33174474 PMCID: PMC8581709 DOI: 10.1177/0267659120967194] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [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] [Indexed: 11/16/2022]
Abstract
AIM Patients with cardiogenic shock or ARDS, for example, in COVID-19/SARS-CoV-2, may require extracorporeal membrane oxygenation (ECMO). An ECLS/ECMO model simulating challenging vascular anatomy is desirable for cannula insertion training purposes. We assessed the ability of various 3D-printable materials to mimic the penetration properties of human tissue by using porcine aortae. METHODS A test bench for needle penetration and piercing in sampled porcine aorta and preselected 3D-printable polymers was assembled. The 3D-printable materials had Shore A hardness of 10, 20, and 50. 17G Vygon 1.0 × 1.4 mm × 70 mm needles were used for penetration tests. RESULTS For the porcine tissue and Shore A 10, Shore A 20, and Shore A 50 polymers, penetration forces of 0.9036 N, 0.9725 N, 1.0386 N, and 1.254 N were needed, respectively. For piercing through the porcine tissue and Shore A 10, Shore A 20, and Shore A 50 polymers, forces of 0.8399 N, 1.244 N, 1.475 N, and 1.482 N were needed, respectively. ANOVA showed different variances among the groups, and pairwise two-tailed t-tests showed significantly different needle penetration and piercing forces, except for penetration of Shore A 10 and 20 polymers (p = 0.234 and p = 0.0857). Significantly higher forces were required for all other materials. CONCLUSION Shore A 10 and 20 polymers have similar needle penetration properties compared to the porcine tissue. Significantly more force is needed to pierce through the material fully. The most similar tested material to porcine aorta for needle penetration and piercing in ECMO-implantation is the silicon Shore A 10 polymer. This silicon could be a 3D-printable material in surgical training for ECMO-implantation.
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Affiliation(s)
- Christoph Salewski
- Department of Thoracic and Cardiovascular Surgery, University Medical Center Tübingen, Tübingen, Germany
| | - Sebastian Spintzyk
- Section for Medical Material Science & Technology at the Department of Thoracic and Cardiovascular Surgery, University Medical Center Tübingen, Tübingen, Germany
| | - Thore von Steuben
- Section for Medical Material Science & Technology at the Department of Thoracic and Cardiovascular Surgery, University Medical Center Tübingen, Tübingen, Germany
| | - Rodrigo Sandoval Boburg
- Department of Thoracic and Cardiovascular Surgery, University Medical Center Tübingen, Tübingen, Germany
| | - Attila Nemeth
- Department of Thoracic and Cardiovascular Surgery, University Medical Center Tübingen, Tübingen, Germany
| | - Christine Schille
- Section for Medical Material Science & Technology at the Department of Thoracic and Cardiovascular Surgery, University Medical Center Tübingen, Tübingen, Germany
| | - Metesh Acharya
- Department of Cardiac Surgery, Glenfield Hospital, Leicester, UK
| | - Jürgen Geis-Gerstorfer
- Section for Medical Material Science & Technology at the Department of Thoracic and Cardiovascular Surgery, University Medical Center Tübingen, Tübingen, Germany
| | - Hans-Peter Wendel
- Department of Thoracic and Cardiovascular Surgery, University Medical Center Tübingen, Tübingen, Germany
| | - Aron-Frederik Popov
- Department of Thoracic and Cardiovascular Surgery, University Medical Center Tübingen, Tübingen, Germany
| | - Christian Schlensak
- Department of Thoracic and Cardiovascular Surgery, University Medical Center Tübingen, Tübingen, Germany
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Sawada T, Schille C, Schweizer E, Geis-Gerstorfer J, Takemoto S. Bond strength of commercial veneering porcelain to experimental cast Ti-Cr alloy. Dent Mater J 2020; 39:825-833. [PMID: 32418951 DOI: 10.4012/dmj.2019-245] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
This study evaluated bond strengths of three commercial veneering porcelains to experimental cast titanium-chromium (Ti-Cr) alloy and commercially pure titanium (cp-Ti) via three-point bending test. After the bending test, the fractured specimens were analyzed using an electron probe microanalyzer (EPMA). The Ti-Cr specimens showed lower bond strengths than the cp-Ti specimens, irrespective of the layering porcelain material; however, all the strengths exceeded the minimum requirement of ISO 9693-1:2012 (>25 MPa). EPMA revealed that titanium and/or chromium elements were detected on the debonded porcelain surface of the Ti-Cr and cp-Ti specimens in the case of the higher bond strength. Contrastingly, the residual porcelain was retained on the metallic surface in the case of the lower bond strength. Although porcelain bonding to the titanium alloy is influenced by porcelain type, the Ti-Cr alloy could be feasible for porcelain-fused-to-metal restorations.
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Affiliation(s)
- Tomofumi Sawada
- Department of Biomedical Engineering, School of Dentistry, Iwate Medical University.,Section Medical Materials Science and Technology, University Hospital Tübingen
| | - Christine Schille
- Section Medical Materials Science and Technology, University Hospital Tübingen
| | - Ernst Schweizer
- Section Medical Materials Science and Technology, University Hospital Tübingen
| | | | - Shinji Takemoto
- Department of Biomedical Engineering, School of Dentistry, Iwate Medical University
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Li P, Schille C, Schweizer E, Kimmerle-Müller E, Rupp F, Heiss A, Legner C, Klotz UE, Geis-Gerstorfer J, Scheideler L. Selection of extraction medium influences cytotoxicity of zinc and its alloys. Acta Biomater 2019; 98:235-245. [PMID: 30862550 DOI: 10.1016/j.actbio.2019.03.013] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Revised: 02/15/2019] [Accepted: 03/06/2019] [Indexed: 01/22/2023]
Abstract
Zinc (Zn) alloys have been considered as promising absorbable metals, mainly due to their moderate degradation rates ranging between magnesium alloys and iron alloys. The degradation behavior depends on the specific physiological environment. Released metallic ions and corrosion products directly influence biocompatibility. The initial contact of orthopedic implants or vascular stents after implantation will be with blood. In this study, fetal bovine serum (FBS) was used as a model system of blood components. We investigated the influence of FBS on in vitro degradation behavior and cytotoxicity of pure Zn, and Zn-4Ag and Zn-2Ag-1.8Au-0.2 V (wt%) alloys. The initial degradation rates in FBS were assessed and compared with the degradation and toxicity in four other common physiological model systems: DMEM cell culture medium ± FBS and McCoy's 5A medium ± FBS. Test samples in pure FBS showed the highest initial degradation rates, and accordingly, FBS supplemented media accelerated the degradation process as well. Moreover, an extract test according to ISO 10993-5 and -12 with L929 and Saos-2 cells was performed to investigate the role of FBS in the extraction medium. The cytotoxic effects observed in the tests were correlated with FBS-mediated Zn2+ release. These findings have significant implications regarding the selection of appropriate media for in vitro degradation and cytotoxicity evaluation of Zn and its alloys. STATEMENT OF SIGNIFICANCE: Metallic zinc and its alloys have been considered as promising biodegradable metals, mainly due to their moderate degradation rates. However, in vitro cytotoxicity tests according to the current ISO 10993 standard series are not suitable to predict biocompatibility of Zn alloys due to the inconsistent correlation between in vitro and in vitro biocompatibility. In this study, we show that the outcomes of standardized in vitro cytotoxicity tests of Zn and Zn alloys are influenced by fetal bovine serum in the extraction vehicle because FBS promotes Zn2+ release during the extraction process. The results of the study provide significant information for selection of appropriate model systems to evaluate in vitro degradation behavior and cytotoxicity.
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Sawada T, Wagner V, Schille C, Spintzyk S, Schweizer E, Geis-Gerstorfer J. Effect of slow-cooling protocol on biaxial flexural strengths of bilayered porcelain-ceria-stabilized zirconia/alumina nanocomposite (Ce-TZP/A) disks. Dent Mater 2018; 35:270-282. [PMID: 30522698 DOI: 10.1016/j.dental.2018.11.024] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 11/13/2018] [Accepted: 11/15/2018] [Indexed: 10/27/2022]
Abstract
OBJECTIVE The present study investigated the biaxial flexural strengths of bilayered ceria-stabilized zirconia/alumina nanocomposite (Ce-TZP/A) disks with various layering porcelains veneered using a slow-cooling protocol. METHODS Five porcelain materials (VITA VM9, Cercon Ceram Kiss, and Vintage ZR with experimental coefficient of thermal expansions; CTEs of 8.45, 9.04, and 9.61ppm/°C) were veneered on Ce-TZP/A disks and slow-cooled after firing to fabricate bilayered specimens (core-to-porcelain thickness: 0.8mm/1.5mm). Biaxial flexural strengths of the specimens with the porcelain layer in tension were tested based on the piston-on-three-ball method (ISO 6872:2008). The data were statistically analyzed using Weibull distribution and Fisher's exact test. RESULTS Tensile stresses were observed in the entire porcelain layer while compressive stress at the surface of the Ce-TZP/A layer shifted to tensile stress at the interface between the materials. The cases of small CTE mismatches between the materials showed high Weibull characteristic strengths at the internal and external surfaces of the specimens, except the VM9 group (CTE: 9.0-9.2ppm/°C). The maximum tensile stress was observed on the surface of the porcelain layer, where cracks originated and continuously propagated into the Ce-TZP layer. The Ce-TZP/A fractured into two pieces for large CTE mismatches between the materials, resulting in significantly lower flexural strengths than those fracturing into three pieces for small CTE mismatches. SIGNIFICANCE Flexural strengths and fracture behaviors of bilayered porcelain-Ce-TZP/A disks were influenced by the CTE mismatches, and a small CTE mismatch between the materials was preferred when using a slow-cooling protocol.
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Affiliation(s)
- Tomofumi Sawada
- Section Medical Materials Science & Technology, University Hospital Tübingen, Osianderstr. 2-8, 72076 Tübingen, Germany; Department of Biomedical Engineering, Iwate Medical University, 2-1-1 Nishitokuta, Yahaba-cho, Shiwa-gun, Iwate 028-3694, Japan.
| | - Verena Wagner
- Section Medical Materials Science & Technology, University Hospital Tübingen, Osianderstr. 2-8, 72076 Tübingen, Germany.
| | - Christine Schille
- Section Medical Materials Science & Technology, University Hospital Tübingen, Osianderstr. 2-8, 72076 Tübingen, Germany.
| | - Sebastian Spintzyk
- Section Medical Materials Science & Technology, University Hospital Tübingen, Osianderstr. 2-8, 72076 Tübingen, Germany.
| | - Ernst Schweizer
- Section Medical Materials Science & Technology, University Hospital Tübingen, Osianderstr. 2-8, 72076 Tübingen, Germany.
| | - Jürgen Geis-Gerstorfer
- Section Medical Materials Science & Technology, University Hospital Tübingen, Osianderstr. 2-8, 72076 Tübingen, Germany.
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Unkovskiy A, Bui PHB, Schille C, Geis-Gerstorfer J, Huettig F, Spintzyk S. Objects build orientation, positioning, and curing influence dimensional accuracy and flexural properties of stereolithographically printed resin. Dent Mater 2018; 34:e324-e333. [PMID: 30293688 DOI: 10.1016/j.dental.2018.09.011] [Citation(s) in RCA: 151] [Impact Index Per Article: 25.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Revised: 09/20/2018] [Accepted: 09/22/2018] [Indexed: 11/16/2022]
Abstract
OBJECTIVE To evaluate the influence of printing parameters on flexural properties and accuracy of SLA-printed standard objects. METHODS Thirty specimens were printed in 0°, 45° and 90° orientation. Fourth nine more specimens were printed evenly on the build platform. forty more specimens were printed and polymerized with three curing unit. Length, height and width was measured three times for each specimen and compared to the original dimensions. Afterwards all specimens underwent a three-point-bending test to assess their flexural properties. One way ANOVA and the Post-Hoc all pairs Tukey-Kramer HSD test were used for data evaluation. RESULTS The print orientation influences the printing accuracy. The parameters printed along the Z-axis are particularly prone to inaccuracies. Specimens with 45° orientation were found to be the most accurate. Object printed on the borders of build platform a rather prone to inaccuracies than those in the center. The 90° specimens with layer orientation parallel to the axial load showed the superior flexural strength and flexural modulus. The use of different curing unit is unlikely to affect the objects printing accuracy and flexural properties. SIGNIFICANCE The anisotropical behavior of printed specimens with regards to build orientation and positioning was revealed. The understanding of how the adjustable printing parameter influence the printing outcome is important for a precise fabrication of surgical guides. Inaccuracies up to 10% along the Z-axis, as revealed in the present study,may restrict an accurate implant placement.
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Affiliation(s)
- Alexey Unkovskiy
- Department of Prosthodontics at the Centre of Dentistry, Oral Medicine, and Maxillofacial Surgery with Dental School, Tubingen University Hospital, Osianderstr. 2-8, 72076 Tuebingen, Germany; Department of Dental Surgery, Sechenov First Moscow State Medical University, 8-2 Trubetskaya st., 119991 Moscow, Russia.
| | - Phan Hai-Binh Bui
- Section "Medical Materials, Science and Technology" Tuebingen University Hospital, Osianderstr. 2-8, 72076 Tuebingen, Germany
| | - Christine Schille
- Section "Medical Materials, Science and Technology" Tuebingen University Hospital, Osianderstr. 2-8, 72076 Tuebingen, Germany
| | - Juergen Geis-Gerstorfer
- Section "Medical Materials, Science and Technology" Tuebingen University Hospital, Osianderstr. 2-8, 72076 Tuebingen, Germany
| | - Fabian Huettig
- Department of Prosthodontics at the Centre of Dentistry, Oral Medicine, and Maxillofacial Surgery with Dental School, Tubingen University Hospital, Osianderstr. 2-8, 72076 Tuebingen, Germany
| | - Sebastian Spintzyk
- Section "Medical Materials, Science and Technology" Tuebingen University Hospital, Osianderstr. 2-8, 72076 Tuebingen, Germany
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Sawada T, Schille C, Wagner V, Spintzyk S, Schweizer E, Geis-Gerstorfer J. Biaxial flexural strength of the bilayered disk composed of ceria-stabilized zirconia/alumina nanocomposite (Ce-TZP/A) and veneering porcelain. Dent Mater 2018; 34:1199-1210. [DOI: 10.1016/j.dental.2018.05.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Revised: 01/17/2018] [Accepted: 05/02/2018] [Indexed: 10/16/2022]
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Sawada T, Schille C, Zöldföldi J, Schweizer E, Geis-Gerstorfer J, Spintzyk S. Influence of a surface conditioner to pre-sintered zirconia on the biaxial flexural strength and phase transformation. Dent Mater 2018; 34:486-493. [PMID: 29301652 DOI: 10.1016/j.dental.2017.12.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Revised: 06/19/2017] [Accepted: 12/15/2017] [Indexed: 10/18/2022]
Abstract
OBJECTIVES To assess the influence of a surface conditioner applied to pre-sintered yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) on the biaxial flexural strength and phase transformation. METHODS Conditioner-coated specimens (12mm diameter×0.8mm thickness) were prepared by application of a slurry conditioner using a brush on pre-sintered Y-TZP discs, followed by sandblasting with 50-μm Al2O3 after sintering (C-SB) or no further treatment (C-NT). The remaining conditioner-free specimens were subjected to sandblasting before sintering (NC-SB) or were maintained without treatment (NC-NT). Surface roughness measurements and scanning electron microscopy (SEM) in conjunction with energy dispersive X-ray spectroscopy (SEM-EDX) were performed for surface characterizations. The phase transformation of Y-TZP was identified by X-ray diffraction (XRD), and the biaxial flexural strength was measured using the piston-on-three-ball test according to ISO 6872:2015. The data were analyzed using nonparametric Kruskal-Wallis tests and Weibull distributions with the maximum likelihood estimation. RESULTS Sandblasting resulted in significantly rougher surfaces, irrespective of conditioner application. Conditioner layers were observed on surfaces in the C-NT and C-SB specimens. Monoclinic contents were present in a very small amount in the C-SB specimens. Both median biaxial flexural and characteristic strengths of all specimens exceeded ISO 6872:2015 requirements (Class 5: >800MPa), except the NC-SB specimens which showed significantly the lowest strength (p<0.001). Although no statistical difference was observed in Weibull modulus among the specimens (p=0.598), the NC-SB specimens showed the highest. SIGNIFICANCE Surface conditioner application does not affect the biaxial flexural strength and phase stability of Y-TZP and can be considered practical for clinical use.
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Affiliation(s)
- Tomofumi Sawada
- Section Medical Materials Science & Technology, University Hospital Tübingen, Osianderstr. 2-8, 72076 Tübingen, Germany.
| | - Christine Schille
- Section Medical Materials Science & Technology, University Hospital Tübingen, Osianderstr. 2-8, 72076 Tübingen, Germany.
| | - Judit Zöldföldi
- Institute for Materials Science, University of Stuttgart, Pfaffenwaldring 2b, 70569 Stuttgart, Germany.
| | - Ernst Schweizer
- Section Medical Materials Science & Technology, University Hospital Tübingen, Osianderstr. 2-8, 72076 Tübingen, Germany.
| | - Jürgen Geis-Gerstorfer
- Section Medical Materials Science & Technology, University Hospital Tübingen, Osianderstr. 2-8, 72076 Tübingen, Germany.
| | - Sebastian Spintzyk
- Section Medical Materials Science & Technology, University Hospital Tübingen, Osianderstr. 2-8, 72076 Tübingen, Germany.
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Al Qahtani WM, Schille C, Spintzyk S, Al Qahtani MS, Engel E, Geis-Gerstorfer J, Rupp F, Scheideler L. Effect of surface modification of zirconia on cell adhesion, metabolic activity and proliferation of human osteoblasts. ACTA ACUST UNITED AC 2017; 62:75-87. [DOI: 10.1515/bmt-2015-0139] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Accepted: 03/09/2016] [Indexed: 11/15/2022]
Abstract
AbstractTitanium dental implants with sandblasted and/or acid-etched surfaces have shown clinical superiority in comparison to their smooth, machined counterparts, and are now state of the art. Sandblasting of finished, sintered zirconia implants, however, will damage the surface structure and affect the mechanical properties. To improve osseointegration of zirconia dental implants without impairing the original mechanical strength by crack initiation and partial phase transformation from tetragonal to monoclinic, roughening of the zirconia surface by sandblasting before the final sintering step was employed. Impact of the treatments on cellular reactions of SAOS-2 human osteoblast-like cells was investigated. Sandblasting of Yttrium-stabilized zirconia (Y-TZP) with 120 μm and 250 μm Al
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Spintzyk S, Yamaguchi K, Sawada T, Schille C, Schweizer E, Ozeki M, Geis-Gerstorfer J. Influence of the Conditioning Method for Pre-Sintered Zirconia on the Shear Bond Strength of Bilayered Porcelain/Zirconia. Materials (Basel) 2016; 9:ma9090765. [PMID: 28773885 PMCID: PMC5457043 DOI: 10.3390/ma9090765] [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] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Revised: 08/25/2016] [Accepted: 09/02/2016] [Indexed: 11/17/2022]
Abstract
This study evaluated the bond strength of veneering porcelain with an experimental conditioner-coated zirconia. Pre-sintered Y-TZP specimens (n = 44) were divided in two groups based on conditioning type. After sintering, all sample surfaces were sandblasted and layered with veneering porcelain. Additionally, half of the specimens in each group underwent thermal cycling (10,000 cycles, 5–55 °C), and all shear bond strengths were measured. After testing, the failure mode of each fractured specimen was determined. Differences were tested by parametric and Fisher’s exact tests (α = 0.05). The differences in bond strength were not statistically significant. Adhesive fractures were dominantly observed for the non-thermal cycled specimens. After thermal cycling, the conditioner-coated group showed cohesive and mixed fractures (p = 0.0021), whereas the uncoated group showed more adhesive fractures (p = 0.0021). Conditioning of the pre-sintered Y-TZP did not change the shear bond strength of the veneering porcelain, but did improve the failure mode after thermal cycling.
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Affiliation(s)
- Sebastian Spintzyk
- Section Medical Materials Science & Technology, University Hospital Tübingen, Osiander Strasse 2-8, Tübingen 72076, Germany.
| | - Kikue Yamaguchi
- Department of Implant Dentistry, Showa University School of Dentistry, 2-1-1 Kitasenzoku, Ota-ku, Tokyo 145-8515, Japan.
| | - Tomofumi Sawada
- Section Medical Materials Science & Technology, University Hospital Tübingen, Osiander Strasse 2-8, Tübingen 72076, Germany.
| | - Christine Schille
- Section Medical Materials Science & Technology, University Hospital Tübingen, Osiander Strasse 2-8, Tübingen 72076, Germany.
| | - Ernst Schweizer
- Section Medical Materials Science & Technology, University Hospital Tübingen, Osiander Strasse 2-8, Tübingen 72076, Germany.
| | - Masahiko Ozeki
- Department of Implant Dentistry, Showa University School of Dentistry, 2-1-1 Kitasenzoku, Ota-ku, Tokyo 145-8515, Japan.
| | - Jürgen Geis-Gerstorfer
- Section Medical Materials Science & Technology, University Hospital Tübingen, Osiander Strasse 2-8, Tübingen 72076, Germany.
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Jilcott Pitts SB, Graham J, Mojica A, Stewart L, Walter M, Schille C, McGinty J, Pearsall M, Whitt O, Mihas P, Bradley A, Simon C. Implementing healthier foodservice guidelines in hospital and federal worksite cafeterias: barriers, facilitators and keys to success. J Hum Nutr Diet 2016; 29:677-686. [DOI: 10.1111/jhn.12380] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
| | - J. Graham
- North Carolina Institute for Public Health; University of North Carolina at Chapel Hill; Chapel Hill NC USA
| | - A. Mojica
- Public Health Executive Leadership Program; University of North Carolina at Chapel Hill; Chapel Hill NC USA
| | - L. Stewart
- Department of Nutrition; North Carolina Institute for Public Health; University of North Carolina at Chapel Hill; Chapel Hill NC USA
| | - M. Walter
- Department of Nutrition; North Carolina Institute for Public Health; University of North Carolina at Chapel Hill; Chapel Hill NC USA
| | - C. Schille
- Department of Nutrition; North Carolina Institute for Public Health; University of North Carolina at Chapel Hill; Chapel Hill NC USA
| | - J. McGinty
- Department of Nutrition; North Carolina Institute for Public Health; University of North Carolina at Chapel Hill; Chapel Hill NC USA
| | - M. Pearsall
- Department of Nutrition; North Carolina Institute for Public Health; University of North Carolina at Chapel Hill; Chapel Hill NC USA
| | - O. Whitt
- Department of Public Health; East Carolina University; Greenville NC USA
| | - P. Mihas
- Odum Institute; University of North Carolina at Chapel Hill; Chapel Hill NC USA
| | - A. Bradley
- Partnership for a Healthier America; Washington DC USA
| | - C. Simon
- Partnership for a Healthier America; Washington DC USA
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Al Bakkar H, Spintzyk S, Schille C, Schweizer E, Geis-Gerstorfer J, Rupp F. Influence of a bonding agent on the bond strength between a dental Co-Cr alloy and nine different veneering porcelains. BIOMED ENG-BIOMED TE 2016; 61:509-517. [PMID: 26966925 DOI: 10.1515/bmt-2015-0101] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Accepted: 02/02/2016] [Indexed: 11/15/2022]
Abstract
AbstractAdequate bonding between dental veneering porcelains and non-precious metal alloys is a main factor for the long-term functionality of porcelain fused to metal restorations. Although a huge number of veneering porcelains are on the market, only few studies have reported about the role of bonding agents for the bond strength at their respective interface to cobalt-chromium (Co-Cr). The aim of this study was to compare the influence of a metal-ceramic bonding agent for Co-Cr alloys on the bond strength of metal-ceramic systems. The bond strength test was done according to ISO 9693 with additional detection of the first acoustic crack initiated signal while testing. The bonding agent had only minor effects on the bond strength of the different Co-Cr/ceramic systems. Only three of the nine studied systems showed statistically significant differences (p<0.05) upon applying the bonding agent. Scanning electron microscopy (SEM) showed cracks predominantly caused by adhesive failure. Based on this study, Co-Cr alloys veneered with porcelains with and without a bonding agent exceeded the minimum bond strength of 25 MPa required according to ISO 9693. However, if bond strength values based on acoustic signals were calculated, values below the threshold of 25 MPa could be observed. Such findings are important for failures caused by the occurrence of early cracks.
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Abstract
OBJECTIVE Recently there has been talk of the use of full-contour solid zirconia crowns or bridge restorations with no porcelain overlay. This could be a useful solution for patients with bruxism or limited interocclusal space. However, the hardness of zirconia could affect the opposite natural dentition. The aim of this in-vitro study was to investigate the role of surface treatments on the wear of a zirconia material and its antagonist. MATERIALS AND METHODS Fifty plates (10 × 10 × 1 mm) made of zirconia (LavaMulti(™) ZrO2, 3M ESPE), divided into five equal groups, were sandblasted and ground under standardized conditions with a fine-grit diamond bur (Komet Brasseler, Germany) to simulate clinical conditions. Group (a) was only fired, (b) was fired and sandblasted, (c) only ground, (d) was ground and additionally polished (EVE Ceramic Polishing-Set, Pforzheim) and (e) was ground and glazed. Wear behavior was measured with a pin-on-disk apparatus ABREX against 6 mm steatite balls as antagonists (45°, 5 N load, 5000 cycles, water). The amount of wear was determined topographically using a 3-D profilometer (Concept 3D, Mahr, Germany) by measuring the height loss of the antagonist and the depth of wear Pt of the zirconia. RESULTS In groups (a), (b), (c) and (d) the wear value Pt could not be determined (<1 μm). Wear values of the antagonists (steatite balls) revealed a similar outcome in contact with (b), (c) and (e) in the range of 81-85 μm, whereas (e) was more abrasive but not significantly. A noticeable difference in the wear of the antagonist showed group (d) to have the smallest value. CONCLUSION Polished zirconia seems to have the lowest wear on the antagonists, in contrast with the other kinds of surface treatment.
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Affiliation(s)
- Leonidas Kontos
- University of Tuebingen, Department of Prosthodontics, Section Medical Materials & Technology, Tuebingen, Germany.
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Koos B, Höller J, Schille C, Godt A. Time-dependent analysis and representation of force distribution and occlusion contact in the masticatory cycle. J Orofac Orthop 2012; 73:204-14. [DOI: 10.1007/s00056-012-0075-2] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2011] [Accepted: 01/11/2012] [Indexed: 11/30/2022]
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Schleicher M, Hansmann J, Elkin B, Kluger PJ, Liebscher S, Huber AJ, Fritze O, Schenke-Layland K, Schille C, Müller M, Walles H, Wendel HP, Stock U. In vivo endothelialization of cardiovascular structures using oligonucleotides and diX AM surface coating. Thorac Cardiovasc Surg 2011. [DOI: 10.1055/s-0030-1268966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Geis-Gerstorfer J, Goldammer C, Schille C. Influence of surface finishing on flexural strength of veneered zirconia. Dent Mater 2010. [DOI: 10.1016/j.dental.2010.08.117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Schille C, Aleksandrova V, Hausch G, Wedenig G, Geis-Gerstorfer J. Fretting corrosion of CoCr alloys with different Cr content. Dent Mater 2009. [DOI: 10.1016/j.dental.2009.01.076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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