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Sugiura Y, Yamada E, Horie M. Interlayer expansion of octacalcium phosphate via forced oxidation of the intercalated molecules within its interlayers. Phys Chem Chem Phys 2023; 25:26640-26647. [PMID: 37772427 DOI: 10.1039/d3cp01992f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/30/2023]
Abstract
Octacalcium phosphate (OCP), a precursor to apatite, has a layered structure that allows various molecules to be intercalated within its interlayers. Previous research on the phase conversion process of OCP to apatite indicated that the layered structures typically collapse due to the shrinking of the OCP layers. In contrast, this study presents a novel phenomenon involving OCP layer expansion during phase conversion. This expansion is based on a forced oxidation process of the intercalated molecules within the hydrous layers of OCP. By introducing NaClO to an OCP interlayer containing dithiodiglycolic acid (DSG), the OCP layers are expanded. This process involves DSG decomposition through its reaction with NaClO. Specifically, the process occurs when a DSG-substituted OCP (containing disulfide bonds (-S-S-)) is immersed in a NaClO solution. This is the first study to report the expansion phenomenon during the phase conversion process from OCP to apatite, providing a new perspective to the conventional understanding that these layers only shrink.
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Affiliation(s)
- Yuki Sugiura
- Health and Medical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 2217-14 Hayashi-cho, Takamatsu, Kagawa 761-0395, Japan.
- Research Planning Office, Headquarter of Department of Life Science and Biotechnology, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Umezono, Tsukuba, Ibaraki 305-3305, Japan
| | - Etsuko Yamada
- Health and Medical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 2217-14 Hayashi-cho, Takamatsu, Kagawa 761-0395, Japan.
| | - Masanori Horie
- Health and Medical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 2217-14 Hayashi-cho, Takamatsu, Kagawa 761-0395, Japan.
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Suzuki O, Hamai R, Sakai S. The material design of octacalcium phosphate bone substitute: increased dissolution and osteogenecity. Acta Biomater 2023; 158:1-11. [PMID: 36581004 DOI: 10.1016/j.actbio.2022.12.046] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 12/16/2022] [Accepted: 12/21/2022] [Indexed: 12/29/2022]
Abstract
Octacalcium phosphate (OCP) has been advocated as a precursor of bone apatite crystals. Recent studies have shown that synthetic OCP exhibits highly osteoconductive properties as a bone substitute material that stems from its ability to activate bone tissue-related cells, such as osteoblasts, osteocytes, and osteoclasts. Accumulated experimental evidence supports the proposition that the OCP-apatite phase conversion under physiological conditions increases the stimulatory capacity of OCP. The conversion of OCP progresses by hydrolysis toward Ca-deficient hydroxyapatite with Ca2+ ion incorporation and inorganic phosphate ion release with concomitant increases in the solid Ca/P molar ratio, specific surface area, and serum protein adsorption affinity. The ionic dissolution rate during the hydrolysis reaction was controlled by introducing a high-density edge dislocation within the OCP lattice by preparing it through co-precipitation with gelatin. The enhanced dissolution intensifies the material biodegradation rate and degree of osteogenecity of OCP. Controlling the biodegradation rate relative to the dissolution acceleration may be vital for controlling the osteogenecity of OCP materials. This study investigates the effects of the ionic dissolution of OCP, focusing on the structural defects in OCP, as the enhanced metastability of the OCP phase modulates biodegradability followed by new bone formation. STATEMENT OF SIGNIFICANCE: Octacalcium phosphate (OCP) is recognized as a highly osteoconductive material that is biodegradable by osteoclastic resorption, followed by new bone formation by osteoblasts. However, if the degradation rate of OCP is increased by maintaining the original osteoconductivity or acquiring a bioactivity better than its current properties, then early replacement with new bone can be expected. Although cell introduction or growth factor addition by scaffold materials is the standard method for tissue engineering, material activity can be augmented by introducing dislocations into the lattice of the OCP. This review article summarizes the effects of introducing structural defects on activating OCP, which was obtained by co-precipitation with gelatin, as a bone substitute material and the mechanism of improved bone replacement performance.
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Affiliation(s)
- Osamu Suzuki
- Division of Craniofacial Function Engineering, Tohoku University Graduate School of Dentistry, 4-1, Seiryo-machi, Aoba-ku, Sendai 980-8575, Japan.
| | - Ryo Hamai
- Division of Craniofacial Function Engineering, Tohoku University Graduate School of Dentistry, 4-1, Seiryo-machi, Aoba-ku, Sendai 980-8575, Japan
| | - Susumu Sakai
- Division of Craniofacial Function Engineering, Tohoku University Graduate School of Dentistry, 4-1, Seiryo-machi, Aoba-ku, Sendai 980-8575, Japan
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Sayedain SS, Ekrami A, Badrossamay M. Production and characterization of Ti6Al4V/CaP nanocomposite powder for powder-based additive manufacturing systems. POWDER TECHNOL 2021. [DOI: 10.1016/j.powtec.2021.03.046] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Suzuki O, Shiwaku Y, Hamai R. Octacalcium phosphate bone substitute materials: Comparison between properties of biomaterials and other calcium phosphate materials. Dent Mater J 2020; 39:187-199. [PMID: 32161239 DOI: 10.4012/dmj.2020-001] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Octacalcium phosphate (OCP) is a material that can be converted to hydroxyapatite (HA) under physiological environments and is considered a mineral precursor to bone apatite crystals. The structure of OCP consists of apatite layers stacked alternately with hydrated layers, and closely resembles the structure of HA. The performance of OCP as a bone substitute differs from that of HA materials in terms of their osteoconductivity and biodegradability. OCP manifests a cellular phagocytic response through osteoclast-like cells similar to that exhibited by the biodegradable material β-tricalcium phosphate (β-TCP). The use of OCP for human cranial bone defects involves using its granule or composite form with one of the natural polymers, viz., the reconstituted collagen. This review article discusses the differences and similarities in these calcium phosphate (Ca-P)-based materials from the viewpoint of the structure and their material chemistry, and attempts to elucidate why Ca-P materials, particularly OCP, display unique osteoconductive property.
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Affiliation(s)
- Osamu Suzuki
- Division of Craniofacial Function Engineering, Tohoku University Graduate School of Dentistry
| | - Yukari Shiwaku
- Division of Craniofacial Function Engineering, Tohoku University Graduate School of Dentistry
| | - Ryo Hamai
- Division of Craniofacial Function Engineering, Tohoku University Graduate School of Dentistry
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Hamai R, Tsuchiya K, Suzuki O. Adsorption of Serum Albumin onto Octacalcium Phosphate in Supersaturated Solutions Regarding Calcium Phosphate Phases. MATERIALS 2019; 12:ma12142333. [PMID: 31340468 PMCID: PMC6678651 DOI: 10.3390/ma12142333] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 07/16/2019] [Accepted: 07/19/2019] [Indexed: 11/16/2022]
Abstract
Octacalcium phosphate (OCP) has been shown to enhance new bone formation, coupled with its own biodegradation, through osteoblasts and osteoclast-like cell activities concomitant with de novo hydroxyapatite (HA) formation and serum protein accumulation on its surface. However, the nature of the chemical environment surrounding OCP and how it affects its metabolism and regulates protein accumulation is unknown. The present study examined how the degree of supersaturation (DS) affects the bovine serum albumin (BSA) adsorption onto OCP in 150 mM Tris-HCl buffer at 37 °C and pH 7.4, by changing the Ca2+ ion concentration. The amount of BSA adsorbed onto OCP increased as the DS increased. In addition, the amount of newly formed calcium phosphate, which could be OCP, was increased, not only by increases in DS, but also at lower equilibrium concentrations of BSA. The increased adsorption capacity of BSA was likely related to the formation of calcium phosphate on the adsorbed OCP. Together the results suggested that the formation of new calcium phosphate crystals is dependent on both the DS value and the adsorbate protein concentration, which may control serum protein accumulation on the OCP surface in vivo.
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Affiliation(s)
- Ryo Hamai
- Division of Craniofacial Function Engineering, Tohoku University Graduate School of Dentistry, 4-1 Seiryo-machi, Aoba-ku, Sendai 980-8575, Japan
| | - Kaori Tsuchiya
- Division of Craniofacial Function Engineering, Tohoku University Graduate School of Dentistry, 4-1 Seiryo-machi, Aoba-ku, Sendai 980-8575, Japan
| | - Osamu Suzuki
- Division of Craniofacial Function Engineering, Tohoku University Graduate School of Dentistry, 4-1 Seiryo-machi, Aoba-ku, Sendai 980-8575, Japan.
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Shi H, Zhang J, Ye X, Wu T, Yu T, Ye J. Formation and stability of well-crystallized metastable octacalcium phosphate at high temperature by regulating the reaction environment with carbamide. CrystEngComm 2019. [DOI: 10.1039/c9ce00677j] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The formation and stability of pure well-crystallized metastable OCP were regulated under carbamide-mediated reaction conditions through the co-existing conversion mechanisms.
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Affiliation(s)
- Haishan Shi
- School of Materials Science and Engineering
- South China University of Technology
- Guangzhou 510640
- China
- National Engineering Research Center for Tissue Restoration and Reconstruction
| | - Jing Zhang
- Centre for Oral Clinical & Translation Sciences
- Faculty of Dentistry, Oral & Craniofacial Sciences
- King's College London
- London SE1 9RT
- UK
| | - Xiaoling Ye
- School of Materials Science and Engineering
- South China University of Technology
- Guangzhou 510640
- China
- National Engineering Research Center for Tissue Restoration and Reconstruction
| | - Tingting Wu
- The First Affiliated Hospital
- Jinan University
- Guangzhou 510632
- China
| | - Tao Yu
- College of Chemistry and Materials Science
- Jinan University
- Guangzhou 510632
- China
| | - Jiandong Ye
- School of Materials Science and Engineering
- South China University of Technology
- Guangzhou 510640
- China
- National Engineering Research Center for Tissue Restoration and Reconstruction
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Fabrication of carbonate apatite blocks from octacalcium phosphate blocks through different phase conversion mode depending on carbonate concentration. J SOLID STATE CHEM 2018. [DOI: 10.1016/j.jssc.2018.08.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Sugiura Y, Munar ML, Ishikawa K. Fabrication of octacalcium phosphate block through a dissolution-precipitation reaction using a calcium sulphate hemihydrate block as a precursor. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2018; 29:151. [PMID: 30264167 DOI: 10.1007/s10856-018-6162-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Accepted: 09/18/2018] [Indexed: 05/15/2023]
Abstract
Although octacalcium phosphate (OCP) powder and a collagen/gelatin composite demonstrate good potential as bone substitutes, an OCP block has not been fabricated to date. In this study, the feasibility of fabricating an OCP block was evaluated through a dissolution-precipitation reaction using a calcium sulfate hemihydrate (CSH) block as a precursor. When the block was immersed in a phosphate salt solution, its composition changed to that of OCP, while its structure was maintained. The diametral tensile strength (DTS) of the OCP block was 1.0 ± 0.2 MPa. The macroporosity and microporosity of the OCP block were 33.4 ± 4.5% and, 69.0 ± 1.6%, respectively. New bone attached well to the OCP block, and this block was partially replaced by bone 2 weeks after implantation. Four weeks after implantation, the surface of the OCP block was nearly covered with new bone and ~30% of the block was replaced by new bone, while no replacement by bone was observed in the case of a hydroxyapatite (HAp) block used as a control. It is concluded that OCP blocks are potentially suitable for their use as artificial bone substitutes.
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Affiliation(s)
- Yuki Sugiura
- Department of Biomaterials, Faculty of Dental Science, Kyushu University, 3-1-1, Maidashi, Higashi, Fukuoka, 812-8532, Japan.
- Health Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 2217-14 Hayashi-cho, Takamatsu, Kagawa, 761-0395, Japan.
| | - Melvin L Munar
- Department of Biomaterials, Faculty of Dental Science, Kyushu University, 3-1-1, Maidashi, Higashi, Fukuoka, 812-8532, Japan
| | - Kunio Ishikawa
- Department of Biomaterials, Faculty of Dental Science, Kyushu University, 3-1-1, Maidashi, Higashi, Fukuoka, 812-8532, Japan
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9
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Mechanically Robust 3D Graphene–Hydroxyapatite Hybrid Bioscaffolds with Enhanced Osteoconductive and Biocompatible Performance. CRYSTALS 2018. [DOI: 10.3390/cryst8020105] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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Altmann ASP, Collares FM, Balbinot GDS, Leitune VCB, Takimi AS, Samuel SMW. Niobium pentoxide phosphate invert glass as a mineralizing agent in an experimental orthodontic adhesive. Angle Orthod 2017; 87:759-765. [PMID: 28686093 DOI: 10.2319/122417-140.1] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
OBJECTIVE The aim of this study was to develop an experimental orthodontic adhesive and evaluate how adding phosphate invert glass containing niobium pentoxide (PIG-Nb) affected the adhesive's properties. MATERIAL AND METHODS PIG-Nb was added at 1, 2.5, and 5 wt% to experimental adhesive (75 wt% bisphenol A methacrylate [BisGMA], 25 wt% triethylene glycol dimethacrylate [TEGDMA], 5 wt% colloidal silica and photoinitiator system). The adhesives were evaluated for mineral deposition, degree of conversion (DC), softening solvent by Knoop microhardness (KNH) variation, pH changes, and shear bond strength (SBS). One-way analysis of variance (ANOVA) (DC and ΔKHN%), two-way ANOVA (SBS), repeated measures ANOVA (pH), and paired test (KNH1 and KNH2) were used at a significance level of P < .05. RESULTS Adding PIG-Nb to orthodontic adhesives induced deposition on its surface associated with a constant neutral pH. The SBS increased after immersion in artificial saliva, and the PIG-Nb5 exhibited less softening. CONCLUSION The addition of PIG-Nb into orthodontic adhesives induced mineral deposition. Experimental orthodontic adhesive containing 5% wt of PIG-Nb exhibited increased mineral deposition and suitable properties for orthodontic applications.
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11
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Stojanović ZS, Ignjatović N, Wu V, Žunič V, Veselinović L, Škapin S, Miljković M, Uskoković V, Uskoković D. Hydrothermally processed 1D hydroxyapatite: Mechanism of formation and biocompatibility studies. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2016; 68:746-757. [PMID: 27524076 PMCID: PMC4987716 DOI: 10.1016/j.msec.2016.06.047] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Revised: 05/22/2016] [Accepted: 06/13/2016] [Indexed: 12/23/2022]
Abstract
Recent developments in bone tissue engineering have led to an increased interest in one-dimensional (1D) hydroxyapatite (HA) nano- and micro-structures such as wires, ribbons and tubes. They have been proposed for use as cell substrates, reinforcing phases in composites and carriers for biologically active substances. Here we demonstrate the synthesis of 1D HA structures using an optimized, urea-assisted, high-yield hydrothermal batch process. The one-pot process, yielding HA structures composed of bundles of ribbons and wires, was typified by the simultaneous occurrence of a multitude of intermediate reactions, failing to meet the uniformity criteria over particle morphology and size. To overcome these issues, the preparation procedure was divided to two stages: dicalcium phosphate platelets synthesized in the first step were used as a precursor for the synthesis of 1D HA in the second stage. Despite the elongated particle morphologies, both the precursor and the final product exhibited excellent biocompatibility and caused no reduction of viability when tested against osteoblastic MC3T3-E1 cells in 2D culture up to the concentration of 2.6mg/cm(2). X-ray powder diffraction combined with a range of electron microscopies and laser diffraction analyses was used to elucidate the formation mechanism and the microstructure of the final particles. The two-step synthesis involved a more direct transformation of DCP to 1D HA with the average diameter of 37nm and the aspect ratio exceeding 100:1. The comparison of crystalline domain sizes along different crystallographic directions showed no signs of significant anisotropy, while indicating that individual nanowires are ordered in bundles in the b crystallographic direction of the P63/m space group of HA. Intermediate processes, e.g., dehydration of dicalcium phosphate, are critical for the formation of 1D HA alongside other key aspects of this phase transformation, it must be investigated in more detail in the continuous design of smart HA micro- and nano-structures with advanced therapeutic potentials.
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Affiliation(s)
- Zoran S Stojanović
- Centre for Fine Particles Processing and Nanotechnologies, Institute of Technical Sciences of the Serbian Academy of Sciences and Arts, Knez Mihailova 35/4, 11000 Belgrade, Serbia
| | - Nenad Ignjatović
- Centre for Fine Particles Processing and Nanotechnologies, Institute of Technical Sciences of the Serbian Academy of Sciences and Arts, Knez Mihailova 35/4, 11000 Belgrade, Serbia
| | - Victoria Wu
- Advanced Materials and Nanobiotechnology Laboratory, Department of Bioengineering, University of Illinois, 851 South Morgan Street, Chicago, IL 60607-7052, USA
| | - Vojka Žunič
- Advanced Materials Department, Jožef Stefan Institute, Jamova cesta 39, 1000 Ljubljana, Slovenia
| | - Ljiljana Veselinović
- Centre for Fine Particles Processing and Nanotechnologies, Institute of Technical Sciences of the Serbian Academy of Sciences and Arts, Knez Mihailova 35/4, 11000 Belgrade, Serbia
| | - Srečo Škapin
- Advanced Materials Department, Jožef Stefan Institute, Jamova cesta 39, 1000 Ljubljana, Slovenia
| | - Miroslav Miljković
- Laboratory for Electron Microscopy, Faculty of Medicine University of Niš, Dr. Zoran Đinđić Boulevard 81, 18 000 Niš, Serbia
| | - Vuk Uskoković
- Advanced Materials and Nanobiotechnology Laboratory, Department of Bioengineering, University of Illinois, 851 South Morgan Street, Chicago, IL 60607-7052, USA; Department of Biomedical and Pharmaceutical Sciences, School of Pharmacy, Chapman University, 9401 Jeronimo Road, Irvine, CA 92618-1908, USA
| | - Dragan Uskoković
- Centre for Fine Particles Processing and Nanotechnologies, Institute of Technical Sciences of the Serbian Academy of Sciences and Arts, Knez Mihailova 35/4, 11000 Belgrade, Serbia.
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Shi FN, Almeida JC, Helguero LA, Fernandes MHV, Knowles JC, Rocha J. Calcium Phosphonate Frameworks for Treating Bone Tissue Disorders. Inorg Chem 2015; 54:9929-35. [DOI: 10.1021/acs.inorgchem.5b01634] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Fa-Nian Shi
- School
of Science, Shenyang University of Technology, 110870 Shenyang, China
| | | | - Luisa A. Helguero
- Organic Chemistry and Natural Products Unit (QOPNA), Department of
Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal
- Institute for Research in Biomedicine−iBiMED,
Health Sciences Program, University of Aveiro, 3810-193 Aveiro, Portugal
| | | | - Jonathan C. Knowles
- Division of Biomaterials and Tissue Engineering,
UCL Eastman Dental Institute, University College London, London, WC1X 8LD, United Kingdom
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Kobayashi K, Anada T, Handa T, Kanda N, Yoshinari M, Takahashi T, Suzuki O. Osteoconductive property of a mechanical mixture of octacalcium phosphate and amorphous calcium phosphate. ACS APPLIED MATERIALS & INTERFACES 2014; 6:22602-11. [PMID: 25478703 DOI: 10.1021/am5067139] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The present study was designed to investigate the extent of osteoconductive property of a mechanical mixture of octacalcium phosphate (OCP) and amorphous calcium phosphate (ACP). OCP was mixed with ACP in granules that had a diameter of 300 and 500 μm, respectively, and at 25, 50, or 75 wt %. The physicochemical characteristics and the osteoconductive properties of the mixtures were compared with OCP alone or ACP alone through implantation into rat critical-sized calvaria defects for up to 12 weeks and simulated body fluid (SBF) immersion for 2 weeks. The mixtures of OCP and ACP, in particular the OCP 25 wt % and ACP 75 wt % (O25A75), had higher radiopacity compared to ACP and OCP alone. O25A75 induced greater enhancement of bone regeneration than ACP alone at 8 weeks and that than OCP alone at 12 weeks. X-ray diffraction and Fourier transform infrared (FTIR) analyses of the retrieved mixtures showed that ACP, OCP, and O25A75 tended to convert to hydroxyapatite (HA) after the implantation, while the structure of OCP remains without complete conversion after SBF immersion. Analyses by FTIR curve fitting of the solids and the degree of supersaturation of the SBF supported the observation that the existence of ACP enhances the kinetics of the conversion. Scanning electron microscopy found that the surface of O25A75 had distinct characteristics with OCP and ACP after SBF immersion. The results suggest that the extent of the osteoconduction of OCP could be controlled by the copresence of ACP most probably through the prevailing dissolution-precipitation of the surface of ACP crystals to form HA.
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Affiliation(s)
- Kazuhito Kobayashi
- Division of Oral and Maxillofacial Surgery and ‡Division of Craniofacial Function Engineering, Tohoku University Graduate School of Dentistry , Sendai, Miyagi 980-8575, Japan
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