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Wang J, Cheng Z, Chen D, Li G, Chen J, Wang K, Xu L, Huang J. An injectable porous bioactive magnesium phosphate bone-cement foamed with calcium carbonate and citric acid for periodontal bone regeneration. J Mech Behav Biomed Mater 2023; 142:105805. [PMID: 37087954 DOI: 10.1016/j.jmbbm.2023.105805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2023] [Revised: 03/20/2023] [Accepted: 03/24/2023] [Indexed: 04/08/2023]
Abstract
Magnesium phosphate cement (MPC) has been evaluated as a novel bone substitute owing to its favorable biocompatibility, plasticity, and osteogenic potential. However, the low porosity of MPC prevents growth factors and osteoblasts from fully growing into the material, thereby limiting its clinical use. In this study, different concentrations (0-5%) of calcium carbonate and citric acid (CA) were used as foaming agents to prepare porous MPC. The MPC containing 3% CaCO3/CA exhibited the best physicochemical properties, including greater porosity, improved injectability, extended setting time, and decreased hydration temperature. The proliferation and adhesion of cells on 3%CaCO3/CA-MPC were higher than those on MPC alone. To explore its osteogenesis in vivo, 3% CaCO3/CA-MPC and Bio-Oss® bone powder were implanted into periodontal bone defects in rats for 4 weeks and 12 weeks, respectively. Micro-CT and histological analysis demonstrated the improved bone regeneration of 3%CaCO3/CA-MPC compared to the blank group (P < 0.05); it had slightly lower bone regeneration than the Bio-Oss® group but no statistical difference. The results indicated that porous MPC foamed with calcium carbonate and CA improved its physicochemical properties and enhanced its biocompatibility, making it a promising material for bone regeneration.
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Baskaran N, Chang YC, Chang CH, Hung SK, Kao CT, Wei Y. Quantify the Protein-Protein Interaction Effects on Adsorption Related Lubricating Behaviors of α-Amylase on a Glass Surface. Polymers (Basel) 2020; 12:E1658. [PMID: 32722491 PMCID: PMC7463787 DOI: 10.3390/polym12081658] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 07/18/2020] [Accepted: 07/22/2020] [Indexed: 11/16/2022] Open
Abstract
Dental ceramic material is one of the widely preferred restorative materials to mimic the natural tooth enamel surface. However, it has continuously been degraded because of low wear resistance during mastication in the oral cavity. The friction involved was reduced by introducing the lubricant saliva protein layers to improve the wear resistance of the dental materials. However, little is understood regarding how the protein-protein interactions (PPI) influence the adsorbed-state structures and lubricating behaviors of saliva proteins on the ceramic material surface. The objective of this study is to quantify the influences of PPI effects on the structural changes and corresponding oral lubrications of adsorbed α-amylase, one of the abundant proteins in the saliva, on the dental ceramic material with glass as a model surface. α-Amylase was first adsorbed to glass surface under varying protein solution concentrations to saturate the surface to vary the PPI effects over a wide range. The areal density of the adsorbed protein was measured as an indicator of the level of PPI effects within the layer, and these values were then correlated with the measurements of the adsorbed protein's secondary structure and corresponding friction coefficient. The decreased friction coefficient value was an indicator of the lubricated surfaces with higher wear resistance. Our results indicate that PPI effects help stabilize the structure of α-amylase adsorbed on glass, and the correlation observed between the friction coefficient and the conformational state of adsorbed α-amylase was apparent. This study thus provides new molecular-level insights into how PPI influences the structure and lubricating behaviors of adsorbed protein, which is critical for the innovations of dental ceramic material designs with improved wear resistance.
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Affiliation(s)
| | | | | | | | | | - Yang Wei
- Department of Chemical Engineering and Biotechnology, National Taipei University of Technology, 1, Section 3, Zhongxiao East Road, Taipei 10608, Taiwan; (N.B.); (Y.-C.C.); (C.-H.C.); (S.-K.H.); (C.-T.K.)
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Chang YC, Su CY, Chang CH, Fang HW, Wei Y. Correlation between Tribological Properties and the Quantified Structural Changes of Lysozyme on Poly (2-hydroxyethyl methacrylate) Contact Lens. Polymers (Basel) 2020; 12:polym12081639. [PMID: 32717989 PMCID: PMC7464607 DOI: 10.3390/polym12081639] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 07/17/2020] [Accepted: 07/17/2020] [Indexed: 12/23/2022] Open
Abstract
The ocular discomfort is the leading cause of contact lens wear discontinuation. Although the tear proteins as a lubricant might improve contact lens adaptation, some in vitro studies suggested that the amount of adsorbed proteins could not simply explain the lubricating performance of adsorbed proteins. The purpose of this study was to quantify the structural changes and corresponding ocular lubricating properties of adsorbed protein on a conventional contact lens material, poly (2-hydroxyethyl methacrylate) (pHEMA). The adsorption behaviors of lysozyme on pHEMA were determined by the combined effects of protein–surface and protein–protein interactions. Lysozyme, the most abundant protein in tear, was first adsorbed onto the pHEMA surface under widely varying protein solution concentrations to saturate the surface, with the areal density of the adsorbed protein presenting different protein–protein effects within the layer. These values were correlated with the measured secondary structures, and corresponding friction coefficient of the adsorbed and protein covered lens surface, respectively. The decreased friction coefficient value was an indicator of the lubricated surfaces with improved adaptation. Our results indicate that the protein–protein effects help stabilize the structure of adsorbed lysozyme on pHEMA with the raised friction coefficient measured critical for the innovation of contact lens material designs with improved adaptation.
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Affiliation(s)
- You-Cheng Chang
- Department of Chemical Engineering and Biotechnology, National Taipei University of Technology, 1, Sec. 3, Zhongxiao E. Rd., Taipei 10608, Taiwan; (Y.-C.C.); (C.-Y.S.); (C.-H.C.)
| | - Chen-Ying Su
- Department of Chemical Engineering and Biotechnology, National Taipei University of Technology, 1, Sec. 3, Zhongxiao E. Rd., Taipei 10608, Taiwan; (Y.-C.C.); (C.-Y.S.); (C.-H.C.)
| | - Chia-Hua Chang
- Department of Chemical Engineering and Biotechnology, National Taipei University of Technology, 1, Sec. 3, Zhongxiao E. Rd., Taipei 10608, Taiwan; (Y.-C.C.); (C.-Y.S.); (C.-H.C.)
| | - Hsu-Wei Fang
- Department of Chemical Engineering and Biotechnology, National Taipei University of Technology, 1, Sec. 3, Zhongxiao E. Rd., Taipei 10608, Taiwan; (Y.-C.C.); (C.-Y.S.); (C.-H.C.)
- Institute of Biomedical Engineering and Nanomedicine, National Health Research Institutes, No. 35, Keyan Road, Zhunan Town, Miaoli County 35053, Taiwan
- Correspondence: (H.-W.F.); (Y.W.)
| | - Yang Wei
- Department of Chemical Engineering and Biotechnology, National Taipei University of Technology, 1, Sec. 3, Zhongxiao E. Rd., Taipei 10608, Taiwan; (Y.-C.C.); (C.-Y.S.); (C.-H.C.)
- Correspondence: (H.-W.F.); (Y.W.)
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Kilic Bektas C, Hasirci V. Cell Loaded GelMA:HEMA IPN hydrogels for corneal stroma engineering. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2019; 31:2. [PMID: 31811387 DOI: 10.1007/s10856-019-6345-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Accepted: 11/16/2019] [Indexed: 06/10/2023]
Abstract
Stroma is the main refractive element of the cornea and damage to it is one of the main causes of blindness. In this study, cell loaded hydrogels of methacrylated gelatin (GelMA) and poly(2-hydroxyethyl methacrylate) (pHEMA) (8:2) interpenetrating network (IPN) hydrogels were prepared as the corneal stroma substitute and tested in situ and in vitro. Compressive modulus of the GelMA hydrogels was significantly enhanced with the addition of pHEMA in the structure (6.53 vs 155.49 kPa, respectively). More than 90% of the stromal keratocytes were viable in the GelMA and GelMA-HEMA hydrogels as calculated by Live-Dead Assay and NIH Image-J program. Cells synthesized representative collagens and proteoglycans in the hydrogels indicating that they preserved their keratocyte functions. Transparency of the cell loaded GelMA-HEMA hydrogels was increased significantly up to 90% at 700 nm during three weeks of incubation and was comparable with the transparency of native cornea. Cell loaded GelMA-HEMA corneal stroma model is novel and reported for the first time in the literature in terms of introduction of cells during the preparation phase of the hydrogels. The appropriate mechanical strength and high transparency of the cell loaded constructs indicates a viable alternative to the current devices used in the treatment of corneal blindness.
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Affiliation(s)
- Cemile Kilic Bektas
- Department of Biological Sciences, Middle East Technical University (METU), Ankara, Turkey
- Department of Biotechnology, METU, Ankara, Turkey
- BIOMATEN, METU Center of Excellence in Biomaterials and Tissue Engineering, Ankara, Turkey
| | - Vasif Hasirci
- Department of Biological Sciences, Middle East Technical University (METU), Ankara, Turkey.
- Department of Biotechnology, METU, Ankara, Turkey.
- BIOMATEN, METU Center of Excellence in Biomaterials and Tissue Engineering, Ankara, Turkey.
- Department of Medical Engineering, Acıbadem Mehmet Ali Aydınlar University, Istanbul, Turkey.
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Kilic Bektas C, Burcu A, Gedikoglu G, Telek HH, Ornek F, Hasirci V. Methacrylated gelatin hydrogels as corneal stroma substitutes: in vivo study. JOURNAL OF BIOMATERIALS SCIENCE-POLYMER EDITION 2019; 30:1803-1821. [DOI: 10.1080/09205063.2019.1666236] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Cemile Kilic Bektas
- Departments of Biological Sciences, Middle East Technical University (METU), Ankara, Turkey
- Department of Biotechnology, Middle East Technical University (METU), Ankara, Turkey
- BIOMATEN, METU Center of Excellence in Biomaterials and Tissue Engineering, Ankara, Turkey
| | - Ayse Burcu
- Eye Clinic, University of Health Sciences, Ankara Training and Research Hospital, Ankara, Turkey
| | - Gokhan Gedikoglu
- Department of Medical Pathology, Hacettepe University, Ankara, Turkey
| | - Hande H. Telek
- Eye Clinic, Beytepe Murat Erdi Eker State Hospital, Ankara, Turkey
| | - Firdevs Ornek
- Eye Clinic, University of Health Sciences, Ankara Training and Research Hospital, Ankara, Turkey
| | - Vasif Hasirci
- Departments of Biological Sciences, Middle East Technical University (METU), Ankara, Turkey
- Department of Biotechnology, Middle East Technical University (METU), Ankara, Turkey
- BIOMATEN, METU Center of Excellence in Biomaterials and Tissue Engineering, Ankara, Turkey
- Department of Medical Engineering, Acıbadem Mehmet Ali Aydınlar University, İstanbul, Turkey
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Li Z, Goh TW, Yam GHF, Thompson BC, Hu H, Setiawan M, Sun W, Riau AK, Tan DT, Khor KA, Mehta JS. A sintered graphene/titania material as a synthetic keratoprosthesis skirt for end-stage corneal disorders. Acta Biomater 2019; 94:585-596. [PMID: 31129362 DOI: 10.1016/j.actbio.2019.05.053] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2019] [Revised: 05/16/2019] [Accepted: 05/20/2019] [Indexed: 01/21/2023]
Abstract
An artificial cornea or keratoprosthesis requires high mechanical strength, good biocompatibility, and sufficient wear and corrosion resistance to withstand the hostile environment. We report a reduced graphene oxide-reinforced titania-based composite for this application. Graphene oxide nanoparticles (GO) and liquid crystalline graphene oxide (LCGO) were the graphene precursors and mixed with titanium dioxide (TiO2) powder. The composites reinforced with reduced GO or LCGO were produced through spark plasma sintering (SPS). The mechanical properties (Young's modulus and hardness), wear behaviour and corrosion resistance were studied using nanoindentation, anoidic polarization, long-term corrosion assay in artificial tear fluid and tribology assay in corroboration with atomic force microscopy and scanning electron microscopy. Biocompatibility was assessed by human corneal stromal cell attachment, survival and proliferation, and DNA damages. Sintered composites were implanted into rabbit corneas to assess for in vivo stability and host tissue responses. We showed that reduced graphene/TiO2 hybrids were safe and biocompatible. In particular, the 1% reduced LCGO/TiO2 (1rLCGO/TiO2) composite was mechanically strong, chemically stable, and showed better wear and corrosion resistance than pure titania and other combinations of graphene-reinforced titania. Hence the 1rLCGO/ TiO2 bioceramics can be a potential skirt biomaterial for keratoprosthesis to treat end-stage corneal blindness. STATEMENT OF SIGNIFICANCE: The osteo-odonto-keratoprosthesis (OOKP) is an artificial cornea procedure used to restore vision in end-stage corneal diseases, however it is contraindicated in young subjects, patients with advanced imflammatory diseases and posterior segment complications. Hence, there is a need of an improved keratoprosthesisskirt material with high mechanical and chemical stability, wear resistance and tissue integration ability. Our study characterized a reduced graphene oxide-reinforced titania-based biomaterial, which demonstrated strong mechanical strength, wear and corrosion resistance, and was safe and biocompatible to human corneal stromal cells. In vivo implantation to rabbit corneas did not cause any immune and inflammation outcomes. In conclusion, this invention is a potential keratoprosthesis skirt biomaterial to withstand the hostile environment in treating end-stage corneal blindness.
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Abstract
The number of blindness is tend to be increased year by year. One of the blindness cause is cornea ulcer.The cause of cornea ulcer is bacteria, fungi, and herpes simplex virus. Cornea transplantation is the only treatment which could widely accepted for blindness. Transplant by donor network becomes the only treatment that is acceptable on a large for blindness. However, treatment donor transplants have many shortcomings in complications post surgery such as host response, donor limitations, incompatibility and the length of time healing. As technology develops, there are many corneal substitutes based on natural ingredients derived from collagen or their derivatives because they promise better properties in biocompatibility. The aim of research are to conduct the synthesis and characterization of collagen- chitosan- glycerol - HPMC as artificial cornea such functional cluster test, cytotoxycity test, morphological test and antibacterial test. Based on functional cluster test, there are functional groups of all components of composite materials. While from cytotoxicity test, all samples have a percentage of living cells above 85%. The morphology test is showed that the pore size of sample B with composition collagen-chitosan-glycerol-HPMC is in accordance with the standard pore size for keratoprothesis. Sample A (collagen-chitosan-glycerol) and sample B (collagen-chitosan-glycerol-HPMC) have strong antibacterial properties.Biocomposite of collagen-chitosan-glycerol could be considered as artificial cornea due to the proximity with the corneal characteristics.
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Mobaraki M, Abbasi R, Omidian Vandchali S, Ghaffari M, Moztarzadeh F, Mozafari M. Corneal Repair and Regeneration: Current Concepts and Future Directions. Front Bioeng Biotechnol 2019; 7:135. [PMID: 31245365 PMCID: PMC6579817 DOI: 10.3389/fbioe.2019.00135] [Citation(s) in RCA: 84] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Accepted: 05/20/2019] [Indexed: 12/13/2022] Open
Abstract
The cornea is a unique tissue and the most powerful focusing element of the eye, known as a window to the eye. Infectious or non-infectious diseases might cause severe visual impairments that need medical intervention to restore patients' vision. The most prominent characteristics of the cornea are its mechanical strength and transparency, which are indeed the most important criteria considerations when reconstructing the injured cornea. Corneal strength comes from about 200 collagen lamellae which criss-cross the cornea in different directions and comprise nearly 90% of the thickness of the cornea. Regarding corneal transparency, the specific characteristics of the cornea include its immune and angiogenic privilege besides its limbus zone. On the other hand, angiogenic privilege involves several active cascades in which anti-angiogenic factors are produced to compensate for the enhanced production of proangiogenic factors after wound healing. Limbus of the cornea forms a border between the corneal and conjunctival epithelium, and its limbal stem cells (LSCs) are essential in maintenance and repair of the adult cornea through its support of corneal epithelial tissue repair and regeneration. As a result, the main factors which threaten the corneal clarity are inflammatory reactions, neovascularization, and limbal deficiency. In fact, the influx of inflammatory cells causes scar formation and destruction of the limbus zone. Current studies about wound healing treatment focus on corneal characteristics such as the immune response, angiogenesis, and cell signaling. In this review, studied topics related to wound healing and new approaches in cornea regeneration, which are mostly related to the criteria mentioned above, will be discussed.
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Affiliation(s)
- Mohammadmahdi Mobaraki
- Biomaterials Group, Department of Biomedical Engineering, Amirkabir University of Technology, Tehran, Iran
| | - Reza Abbasi
- Biomaterials Group, Department of Biomedical Engineering, Amirkabir University of Technology, Tehran, Iran
| | - Sajjad Omidian Vandchali
- Biomaterials Group, Department of Biomedical Engineering, Amirkabir University of Technology, Tehran, Iran
| | - Maryam Ghaffari
- Biomaterials Group, Department of Biomedical Engineering, Amirkabir University of Technology, Tehran, Iran
| | - Fathollah Moztarzadeh
- Biomaterials Group, Department of Biomedical Engineering, Amirkabir University of Technology, Tehran, Iran
| | - Masoud Mozafari
- Department of Tissue Engineering and Regenerative Medicine, Faculty of Advanced Technologies in Medicine, Iran University of Medical Sciences, Tehran, Iran
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Long Y, Zhao X, Liu S, Chen M, Liu B, Ge J, Jia YG, Ren L. Collagen-Hydroxypropyl Methylcellulose Membranes for Corneal Regeneration. ACS OMEGA 2018; 3:1269-1275. [PMID: 30023801 PMCID: PMC6044638 DOI: 10.1021/acsomega.7b01511] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Accepted: 01/10/2018] [Indexed: 06/02/2023]
Abstract
To improve intraocular transparency of collagen matrices, hydroxypropyl methylcellulose (HPMC) was introduced for the first time into cross-linked collagen to form collagen-HPMC composite membranes. Light transmittance and refractive indices of the membranes are enhanced by incorporation of HPMC in comparison to the control of cross-linked collagen membranes. Maximum light transmittance of the collagen-HPMC membrane was up to 92%. In addition, their permeability of nutrients such as glucose, tryptophan, and NaCl was superior or comparable to that of human corneas. In vitro results demonstrated that the collagen-HPMC membrane supported adhesion and proliferation of human corneal epithelial cells (HCECs), showing good cytocompatibility to HCECs. The corneas maintained a smooth surface and clear stroma postoperatively after 7 months of implantation of collagen-HPMC membranes into the corneas of rabbits. The good intraocular biocompatibility was verified by maintaining a high optical clarity for over 6 months after transplantation. Hematoxylin and eosin staining results showed the growth of stromal keratocytes into the collagen-HPMC implants, indicating the ability of the collagen-HPMC membrane to induce corneal cell regeneration. Taken together, the collagen-HPMC membrane might be a promising candidate for use in corneal repair and regeneration.
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Affiliation(s)
- Yuyu Long
- School
of Materials Science and Engineering, South
China University of Technology, Guangzhou 510641, China
- National
Engineering Research Center for Tissue Restoration and Reconstruction, South China University of Technology, Guangzhou 510006, China
| | - Xuan Zhao
- School
of Materials Science and Engineering, South
China University of Technology, Guangzhou 510641, China
- National
Engineering Research Center for Tissue Restoration and Reconstruction, South China University of Technology, Guangzhou 510006, China
| | - Sa Liu
- School
of Materials Science and Engineering, South
China University of Technology, Guangzhou 510641, China
- National
Engineering Research Center for Tissue Restoration and Reconstruction, South China University of Technology, Guangzhou 510006, China
| | - Min Chen
- State
Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, China
| | - Bingqian Liu
- State
Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, China
| | - Jian Ge
- State
Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, China
| | - Yong-Guang Jia
- School
of Materials Science and Engineering, South
China University of Technology, Guangzhou 510641, China
- National
Engineering Research Center for Tissue Restoration and Reconstruction, South China University of Technology, Guangzhou 510006, China
| | - Li Ren
- School
of Materials Science and Engineering, South
China University of Technology, Guangzhou 510641, China
- National
Engineering Research Center for Tissue Restoration and Reconstruction, South China University of Technology, Guangzhou 510006, China
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12
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Baino F. How can bioactive glasses be useful in ocular surgery? J Biomed Mater Res A 2014; 103:1259-75. [DOI: 10.1002/jbm.a.35260] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Revised: 05/29/2014] [Accepted: 05/31/2014] [Indexed: 11/10/2022]
Affiliation(s)
- Francesco Baino
- Institute of Materials Physics and Engineering, Applied Science and Technology Department; Politecnico di Torino, Corso Duca degli Abruzzi 24 10129 Torino Italy
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Oral O, Lassila LV, Kumbuloglu O, Vallittu PK. Bioactive glass particulate filler composite: Effect of coupling of fillers and filler loading on some physical properties. Dent Mater 2014; 30:570-7. [PMID: 24655591 DOI: 10.1016/j.dental.2014.02.017] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Accepted: 02/20/2014] [Indexed: 11/27/2022]
Abstract
OBJECTIVES The aim of this study was to investigate the effect of silanization of biostable and bioactive glass fillers in a polymer matrix on some of the physical properties of the composite. METHODS The water absorption, solubility, flexural strength, flexural modulus and toughness of different particulate filler composite resins were studied in vitro. Five different specimen groups were analyzed: A glass-free control, a non-silanized bioactive glass, a silanized bioactive glass, a non-silanized biostable glass and a silanized biostable glass groups. All of these five groups were further divided into sub-groups of dry and water-stored materials, both of them containing groups with 3wt%, 6wt%, 9wt% or 12wt% of glass particles (n=8 per group). The silanization of the glass particles was carried out with 2% of gamma-3-methacryloxyproyltrimethoxysilane (MPS). For the water absorption and solubility tests, the test specimens were stored in water for 60 days, and the percentages of weight change were statistically analyzed. Flexural strength, flexural modulus and toughness values were tested with a three-point bending test and statistically analyzed. RESULTS Higher solubility values were observed in non-silanized glass in proportion to the percentage of glass particles. Silanization, on the other hand, decreased the solubility values of both types of glass particles and polymer. While 12wt% non-silanized bioactive glass specimens showed -0.98wt% solubility, 12wt% silanized biostable glass specimens were observed to have only -0.34wt% solubility. The three-point bending results of the dry specimens showed that flexural strength, toughness and flexural modulus decreased in proportion to the increase of glass fillers. The control group presented the highest results (106.6MPa for flexural strength, 335.7kPA for toughness, 3.23GPa for flexural modulus), whereas for flexural strength and toughness, 12wt% of non-silanized biostable glass filler groups presented the lowest (70.3MPa for flexural strength, 111.5kPa for toughness). For flexural modulus on the other hand, 12wt% of silanized biostable glass filler group gave the lowest results (2.57GPa). SIGNIFICANCE The silanization of glass fillers improved the properties of the glass as well as the properties of the composite. Silanization of bioactive glass may protect the glass from leaching at early stage of water storage.
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Affiliation(s)
- Onur Oral
- Department of Biomaterials Science & Turku Clinical Biomaterials Centre-TCBC, Institute of Dentistry, University of Turku, Lemminkäisenkatu 2, FI-20014 Turku, Finland.
| | - Lippo V Lassila
- Department of Biomaterials Science & Turku Clinical Biomaterials Centre-TCBC, Institute of Dentistry, University of Turku, Lemminkäisenkatu 2, FI-20014 Turku, Finland
| | - Ovul Kumbuloglu
- Department of Prosthodontics, Faculty of Dentistry, Ege University, Izmir, Turkey
| | - Pekka K Vallittu
- Department of Biomaterials Science & Turku Clinical Biomaterials Centre-TCBC, Institute of Dentistry, University of Turku, Lemminkäisenkatu 2, FI-20014 Turku, Finland
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Tan XW, Riau A, Shi ZL, Tan ACS, Neoh KG, Khor KA, Beuerman RW, Tan D, Mehta JS. In vitro effect of a corrosive hostile ocular surface on candidate biomaterials for keratoprosthesis skirt. Br J Ophthalmol 2012; 96:1252-8. [PMID: 22802307 PMCID: PMC3432489 DOI: 10.1136/bjophthalmol-2012-301633] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Aim Keratoprosthesis (KPro) devices are prone to long-term corrosion and microbiological assault. The authors aimed to compare the inflammatory response and material dissolution properties of two candidate KPro skirt materials, hydroxyapatite (HA) and titania (TiO2) in a simulated in vitro cornea inflammation environment. Methods Lipopolysaccharide-stimulated cytokine secretions were evaluated with human corneal fibroblasts on both HA and TiO2. Material specimens were subjected to electrochemical and long-term incubation test with artificial tear fluid (ATF) of various acidities. Topography and surface roughness of material discs were analysed by scanning electron microscopy and atomic force microscopy. Results There were less cytokines secreted from human corneal fibroblasts seeded on TiO2 substrates as compared with HA. TiO2 was more resistant to the corrosion effect caused by acidic ATF in contrast to HA. Moreover, the elemental composition of TiO2 was more stable than HA after long-term incubation with ATF. Conclusions TiO2 is more resistant to inflammatory degradation and has a higher corrosion resistance as compared with HA, and in this regard may be a suitable material to replace HA as an osteo-odonto-keratoprosthesis skirt. This would reduce resorption rates for KPro surgery.
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Affiliation(s)
- Xiao Wei Tan
- Tissue Engineering and Stem Cell Research Group, Singapore Eye Research Institute, Singapore
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Tan XW, Beuerman RW, Shi ZL, Neoh KG, Tan D, Khor KA, Mehta JS. In vivo evaluation of titanium oxide and hydroxyapatite as an artificial cornea skirt. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2012; 23:1063-1072. [PMID: 22426652 DOI: 10.1007/s10856-012-4578-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2011] [Accepted: 02/02/2012] [Indexed: 05/31/2023]
Abstract
Keratoprosthetic devices are subject to chronic inflammatory, pathological processes and the external environment that affect their stability and biocompatibility with the ocular surface and adjacent ocular tissues. We compared the corrosion resistance property and tissue-implant reaction of titanium oxide (TiO(2)) with hydroxyapatite (HA) in artificial tear fluid and a rabbit skin implantation model. The dissolution properties of the implant surfaces were evaluated with scanning electronic microscope (SEM) and atomic force microscope (AFM). Tissue inflammatory reactions were evaluated by Hematoxylin & Eosin staining, avidin biotin peroxidase complex (ABC) immunoassay and immunofluorescence. SEM and AFM images showed that there was less pitting corrosion on the surface of TiO(2) implants compared with HA. TiO(2) and HA exhibited a similar pattern of foreign body capsule formation and inflammatory cellular responses. The Collagen I/Collagen III ratio of the TiO(2) capsule was higher than that of the HA capsule. TiO(2) implants possess a high corrosion resistance property both in vitro and in vivo and the inflammatory cellular response to TiO(2) is similar to HA. With regards to corrosion resistance and inflammatory tissue responses, TiO(2) appears to be a promising material for keratoprosthetic skirt devices.
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Affiliation(s)
- Xiao Wei Tan
- Tissue Engineering and Stem Cell Research Group, Singapore Eye Research Institute, Singapore, Singapore
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