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2016, Journal of Materials Science
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2010, Journal of Biomedical Materials Research Part B: Applied Biomaterials
Journal of the Mechanical Behavior of Biomedical Materials
2012, Journal of Tissue Engineering
The vast majority of materials used in bone tissue engineering and regenerative medicine are based on calcium phosphates due to their similarity with the mineral phase of natural bone. Among them, calcium phosphate cements, which are composed of a powder and a liquid that are mixed to obtain a moldable paste, are widely used. These calcium phosphate cement pastes can be injected using minimally invasive surgery and adapt to the shape of the defect, resulting in an entangled network of calcium phosphate crystals. Adding an organic phase to the calcium phosphate cement formulation is a very powerful strategy to enhance some of the properties of these materials. Adding some water-soluble biocompatible polymers in the calcium phosphate cement liquid or powder phase improves physicochemical and mechanical properties, such as injectability, cohesion, and toughness. Moreover, adding specific polymers can enhance the biological response and the resorption rate of the material. The goal of t...
2013, Journal of Biomedical Materials Research Part A
2006, Biomaterials
2011
INTRODUCTION Calcium phosphate cements (CPC) have many uses in orthopaedics as bone void fillers. There are many products on the market intended for various indications. CPCs have very good biological properties and stimulate bone ingrowth while being resorbed. However the handling of CPCs poses a problem. They must be mixed at the time of surgery and setting starts immediately after powder and liquid have been mixed, resulting in a limited working time. The handling is complicated and filter pressing often occurs. To solve this issue water can be exchanged for glycerol as mixing liquid. This allows for a virtually unlimited working time since the setting does not start until the cement is inside the body where it comes into contact with water. There are very few CPCs intended for treatment of vertebral compression fractures. For this indication good injectability and radio-opacity are very important. BaSO4 or ZrO2 are often used as radio-opacifying agents in polymer based bone ceme...
2010, Journal of Materials Science: Materials in Medicine
2019, Advanced Nano-Bio-Materals and Devices
In early 1980-s, researchers discovered self-setting calcium orthophosphate (CaPO4) formulations (initially known as calcium phosphate cements), which were bioactive and biodegradable grafting bioceramics in the form of a powder and a liquid. After mixing, both phases formed pastes of variable viscosity, which set and hardened forming most commonly a bone-like non-stoichiometric calcium deficient hydroxyapatite (CDHA) or brushite and rarely monetite with possible admixtures of un-reacted components. Since all these compounds were found to be biocompartible, bioresorbable and osteoconductive (therefore, in vivo they could be replaced with a newly forming bone), the self-setting CaPO4 formulations appeared to be very promising bioceramics for bone grafting purposes. Furthermore, due to their unique properties such as an easy shaping, moldability and injectability these formulations possess both an easy manipulation and a nearly perfect adaptation to the complex shapes of bone defects, followed by gradual bioresorption and new bone formation, which are additional distinctive advantages. Moreover, their low-temperature setting reactions and intrinsic porosity allow loading them by drugs, biomolecules and even cells for tissue engineering applications. However, due to the ceramic origin, the ordinary self-setting CaPO4 formulations exhibit both a brittle nature and a low bending/tensile strength, prohibiting their use in load-bearing sites; therefore, reinforced formulations have been introduced, which might be described as CaPO4 concretes. Thus, the discovery of self-setting properties opened up a new era in the medical application of CaPO4 and many commercial trademarks have been introduced as a result. Many more formulations are still in experimental stages. In this review, an insight into the self-setting CaPO4 formulations, as excellent bioceramics suitable for both dental and bone grafting applications, has been provided.
2008, Journal of Materials Science
In early 1980s, researchers discovered self-setting calcium orthophosphate cements, which are a bioactive and biodegradable grafting material in the form of a powder and a liquid. Both phases after mixing form a viscous paste that after being implanted sets and hardens within the body as either a non-stoichiometric calcium deficient hydroxyapatite (CDHA) or brushite, sometimes blended with unreacted particles and other phases. As both CDHA and brushite are remarkably biocompartible and bioresorbable (therefore, in vivo they can be replaced with a newly forming bone), calcium orthophosphate cements represent a good correction technique of non-weight-bearing bone fractures or defects and appear to be very promising materials for bone grafting applications. Besides, these cements possess an excellent osteoconductivity, molding capabilities, and easy manipulation. Nearly perfect adaptation to the tissue surfaces in bone defects and a gradual bioresorption followed by new bone formation are additional distinctive advantages of calcium orthophosphate cements. Besides, reinforced formulations are available; those are described as calcium orthophosphate composites. The discovery of self-setting cements has opened up a new era in the medical application of calcium orthophosphates; several commercial formulations have already been introduced as a result. Many more compositions are in experimental stages. In this review, an insight into calcium orthophosphate cements, as excellent biomaterials suitable for both dental and bone grafting application, has been provided.
2010, Materials Science Forum
This review discusses and summarizes the recent developments and advances in the use of biodegradable materials for bone repair purposes. The choice between using degradable and non-degradable devices for orthopedic and maxillofacial applications must be carefully weighed. Traditional biodegradable devices for osteosynthesis have been successful in low or mild load bearing applications. However, continuing research and recent developments in the field of material science has resulted in development of biomaterials with improved strength and mechanical properties. For this purpose, biodegradable materials, including polymers, ceramics and magnesium alloys have attracted Materials 2015, 8 5745 much attention for osteologic repair and applications. The next generation of biodegradable materials would benefit from recent knowledge gained regarding cell material interactions, with better control of interfacing between the material and the surrounding bone tissue. The next generations of biodegradable materials for bone repair and regeneration applications require better control of interfacing between the material and the surrounding bone tissue. Also, the mechanical properties and degradation/resorption profiles of these materials require further improvement to broaden their use and achieve better clinical results.
2014, Journal of biomedical materials research. Part B, Applied biomaterials
The main goal of this study was to evaluate the effects of incorporation of calcium phosphate (CaP) particles on the physicochemical properties and mineralization capacity of cements in vitro. Herein, two different types of CaP particles were loaded into polymethylmethacrylate (PMMA) cements exhibiting an interconnected porosity created by mixing with carboxymethylcellulose. The incorporation of CaP particles did not influence the maximum polymerization temperature of the porous PMMA, but reduced the porosity and the average pore size. Small CaP particles formed agglomerations within the PMMA pores, whereas big CaP particles were partially embedded in the PMMA matrix and partially exposed to the pores. Both types of CaP particles enhanced the mineralization capacity of PMMA cement without compromising their mechanical properties. The data presented herein suggest that porous PMMA/CaP cements hold strong promise for surgical application in bone reconstruction. © 2014 Wiley Periodical...
2008, Acta Biomaterialia
2013, Journal of Functional Biomaterials
In early 1980s, researchers discovered self-setting calcium orthophosphate cements, which are bioactive and biodegradable grafting bioceramics in the form of a powder and a liquid. After mixing, both phases form pastes, which set and harden forming either a non-stoichiometric calcium deficient hydroxyapatite or brushite. Since both of them are remarkably biocompartible, bioresorbable and osteoconductive, self-setting calcium orthophosphate formulations appear to be promising bioceramics for bone grafting. Furthermore, such formulations possess excellent molding capabilities, easy manipulation and nearly perfect adaptation to the complex shapes of bone defects, followed by gradual bioresorption and new bone formation. In addition, reinforced formulations have been introduced, which might be described as calcium orthophosphate concretes. The discovery of self-setting properties opened up a new era in the medical application of calcium orthophosphates and many commercial trademarks have been introduced as a result. Currently such formulations are widely used as synthetic bone grafts, with several advantages, such as pourability and injectability. Moreover, their low-temperature setting reactions and intrinsic porosity allow loading by drugs, biomolecules and even cells for tissue engineering purposes. In this review, an insight into the self-setting calcium orthophosphate formulations, as excellent bioceramics suitable for both dental and bone grafting applications, has been provided.
2009, Materials
In early 1980s, researchers discovered self-setting calcium orthophosphate cements, which are a bioactive and biodegradable grafting material in the form of a powder and a liquid. Both phases form after mixing a viscous paste that after being implanted, sets and hardens within the body as either a non-stoichiometric calcium deficient hydroxyapatite (CDHA) or brushite, sometimes blended with unreacted particles and other phases. As both CDHA and brushite are remarkably biocompartible and bioresorbable (therefore, in vivo they can be replaced with newly forming bone), calcium orthophosphate cements represent a good correction technique for non-weight-bearing bone fractures or defects and appear to be very promising materials for bone grafting applications. Besides, these cements possess an excellent osteoconductivity, molding capabilities and easy manipulation. Furthermore, reinforced cement formulations are available, which in a certain sense might be described as calcium orthophosphate concretes. The concepts established by calcium orthophosphate cement pioneers in the early 1980s were used as a platform to initiate a new generation of bone substitute materials for commercialization. Since then, advances have been made in the composition, performance and manufacturing; several beneficial formulations have already been introduced as a result. Many other compositions are in experimental stages. In this review, an insight into calcium orthophosphate cements and concretes, as excellent biomaterials suitable for both dental and bone grafting application, has been provided.
Calcium phosphate cements show many advantages comparing to other calcium phosphate‐based materials. The objective of this study was to investigate the influence of paste concentration controlled by liquid‐to‐powder ratio on compressive strength, setting characteristics and phase composition of α‐TCP based calcium phosphate cements. The powder phase consisted of α‐TCP, DCPA, CaCO3 and hydroxyapatite which were mixed with aqueous solutions of 3 wt% H3PO4 at three different liquid‐to‐powder ratios (0.35, 0.40 and 0.45 mL/g). The cements were characterized in terms of setting time, compressive strength and porosity. Also XRD and SEM techniques were employed to evaluate the phase composition and surface morphology of the cements. The results revealed similar phase composition for all samples before and after soaking in Ringer`s solution. Reduction in liquid‐to‐powder ratio led to increment of compressive strength of CPCs from about 15 MPa for the cement with L/P ratio of 0.45 to about 30 MPa for L/R ratio of 0.35 after 7 days soaking in Ringer`s solution. Also by reducing the L/P ratio from 0.45 to 0.35, initial and final setting times of the CPCs decreased 3 and 5 minutes respectively. A highly microporous structure was also obtained for cements with different liquid‐to‐powder ratios.
2013, Advances in Materials Science and Engineering
Injectable load-bearing calcium phosphate scaffolds are synthesized using rod-like mannitol grains as porogen. These degradable injectable strong porous scaffolds, prepared by calcium phosphate cement, could represent a valid solution to achieve adequate porosity requirements while providing adequate support in load-bearing applications. The proposed process for preparing porous injectable scaffolds is as quick and versatile as conventional technologies. Using this method, porous CDHA-based calcium phosphate scaffolds with macropores sizes ranging from 70 to 300 μm, micropores ranging from 5 to 30 μm, and 30% open macroporosity were prepared. The setting time of the prepared scaffolds was 15 minutes. Also their compressive strength and e-modulus, 4.9 MPa and 400 MPa, respectively, were comparable with those of the cancellous bone. Finally, the bioactivity of the scaffolds was confirmed by cell growth with cytoplasmic extensions in the scaffolds in culture, demonstrating that the sca...
2011, International Journal of Materials and Chemistry
In early 1980s, researchers discovered self-setting calcium orthophosphate cements, which are a bioactive and biodegradable grafting material in the form of a powder and a liquid. Both phases after mixing form a viscous paste that after being implanted sets and hardens within the body as either a non-stoichiometric calcium deficient hydroxyapatite (CDHA) or brushite, sometimes blended with un-reacted particles and other phases. As both CDHA and brushite are remarkably biocompartible and bioresorbable (therefore, in vivo they can be replaced with a newly forming bone), self-setting calcium orthophosphate cements represent a good correction technique of non-weight-bearing bone fractures or defects and appear to be very promising materials for bone grafting applications. Besides, these cements possess an excellent osteoconductivity, molding capabilities, and easy manipulation. Nearly perfect adaptation to the tissue surfaces in bone defects and a gradual bioresorption followed by new bone formation are additional distinctive advantages of calcium orthophosphate cements. Besides, reinforced formulations are available; those are described as calcium orthophosphate concretes. Furthermore, formulations with high viscosity, such as pastes and putties are also known. The discovery of self-setting formulations has opened up a new era in the medical application of calcium orthophosphates; several commercial compositions have already been introduced as a result. Many more formulations are in experimental stages. In this review, an insight into the self-setting calcium orthophosphate formulations, as excellent biomaterials suitable for both dental and bone grafting applications, has been provided.
2010, Acta Biomaterialia
SN Applied Sciences
Hydroxyapatite (HAp) with good mechanical properties is a promising material meant for a number of useful bids in dentistry and orthopedic for biomedical engineering applications for drug delivery, bone defect fillers, bone cements, etc. In this paper, a comprehensive review has been done, by reviewing different literatures related to synthesis techniques, mechanical properties and property testing, method of calcination and characterization of hydroxyapatite which are product of catfish and bovine bones. The discussion is in relations of the obligatory features vital to attain the best properties for the envisioned bid of bone graft. The process approaches that are capable of fabricating the essential microstructure and the ways to advance the mechanical properties of natural mined HAp are reviewed. The standard values for tensile strength were found to be within the range of 40–300 MPa, compressive strength was 400–900 MPa, while Elastic modulus was 80–120 GPa and fracture toughne...
2012, Journal of Biomedical Materials Research Part B: Applied Biomaterials
2017, Materials
2008, Journal of Biomedical Materials Research Part A
The state-of-the-art on calcium orthophosphate (CaPO4)-containing biocomposites and hybrid biomaterials suitable for biomedical applications is presented. Since these types of biomaterials offer many significant and exciting possibilities for hard tissue regeneration, this subject belongs to a rapidly expanding area of biomedical research. Through the successful combinations of the desired properties of matrix materials with those of fillers (in such systems, CaPO4 might play either role), innovative bone graft biomaterials can be designed. Various types of CaPO4-based biocomposites and hybrid biomaterials those are either already in use or being investigated for biomedical applications are extensively discussed. Many different formulations in terms of the material constituents, fabrication technologies, structural and bioactive properties, as well as both in vitro and in vivo characteristics have been already proposed. Among the others, the nano-structurally controlled biocomposites, those containing nanodimensional compounds, biomimetically fabricated formulations with collagen, chitin and/or gelatin, as well as various functionally graded structures seem to be the most promising candidates for clinical applications. The specific advantages of using CaPO4-based biocomposites and hybrid biomaterials in the selected applications are highlighted. As the way from a laboratory to a hospital is a long one and the prospective biomedical candidates have to meet many different necessities, the critical issues and scientific challenges that require further research and development are also examined.
2020
Restorative dental materials are of great importance in dentistry for restoring and replacing injured or missed teeth with the purpose of simulating natural teeth functions besides providing translucency and tooth-like color shade. Restorative dental materials are produced as crowns, inlays, onlays, multi-unit fixed dental prostheses, and veneers. These materials are divided into two distinct categories, which are direct and indirect restorative materials.
2013, Materials & Design
2007, Biomaterials
2006, Polymers for Advanced Technologies
The aim of the present study was to develop new materials which could be applicable as bone substitutes or be used in bone tissue engineering. Two types of porous scaffolds based on poly(ε-caprolactone) (PCL) were investigated. Type 1 scaffolds were prepared by solvent casting/particulate leaching technique, using NaCl with the grain size 250–500 µm as a porogen. In the case of Type 2 scaffolds, the biodegradable polymer was blended with calcium carbonate, which, in contrast to NaCl, is not leached out from the product during manufacture, either in the form of calcite powder or aragonite (needle-like crystals). Influence of manufacturing technique and initial substrate composition on product properties was investigated. The tests involved porosity measurements, structure analysis by optical and scanning electron microscopy and mechanical studies (determination of compression strength and modulus). The results indicate the important role of the phase exchange process in the formation of micropores. In this process PCL precipitated from its acetone solution in the presence of water creating microporous three-dimensional polymer structures. The Type 1 scaffolds possessed both micropores and macropores. Good interconnectivity between the pores was observed for samples of the initial porogen content higher than 33%. Microporous samples containing inorganic filler have lower porosity and higher compression strength. For Type 2 scaffolds the shape of filler particles has an important influence on mechanical properties—replacing powder with needle-like crystals (in the same weight amount) results in a three- to five-fold increase in compression modulus. Copyright © 2006 John Wiley & Sons, Ltd.
2011, Recent Patents on Materials …
Hydroxyapatite (HA) is the main mineral component of bone tissue, representing ca. 69 vol% in bone and up to 98 vol% in dental enamel. Its chemical composition close to the mineral phase of bone is the origin of its excellent biocompatibility to tissue bone. Hydroxyapatite has been applied in orthopaedics as block implants, porous, granules and coating material, either dense or porous. However, the application is restricted to non-load bearing application due to its brittleness and low toughness and flexural strength. With this, the development of bioactive dense HA is necessary as it has promising potential in application of load bearing bone implant. Few efforts have been made in developing many methods to produce dense HA. Some of the methods have been combined to prepare dense HA with improved properties. This paper will be discussing the recent progress on efforts which have been done in improving mechanical properties of hydroxyapatite-based dense type biomaterials for load bearing bone substitutes applications. Some recent patents related to dense calcium phosphate are also reviewed.
2015
This study discloses an original process for making calcium phosphate (CaP)/biopolymer nanocomposite fibrous scaffolds by biomimetic in-situ synthesis and electrospinning. Electrospinning (ES) produces non-woven nanofibrous mesh structure with 3D interconnected pores and a high surface area by applying electrostatic force to polymer-based solution. The resulting topography of the scaffolds mimics the natural extracellular matrix of human tissues, with the potential application in tissue engineering, drug delivery, and wound dressing. We have demonstrated that the possibility of inclusion of CaP into biopolymer nanofibers, inspired by mineralized collagen fibrils in bone tissue, makes ES an attractive processing route for preparation of the nanocomposites for bone tissue regeneration. Two different nanocomposite fibers were explored; i) poly(lactic acid) (PLA) with dicalcium phosphate anhydrate (DCPA) and ii) alginate with hydroxyapatite (HAp). In-situ synthesized DCPA in non-aqueous...
Materials
2016, Journal of the mechanical behavior of biomedical materials
Calcium phosphate cements (CPCs) are widely used in bone repair. Currently there are two main types of CPCs, brushite and apatite. The aim of this project was to evaluate the mechanical properties of particularly promising experimental brushite and apatite formulations in comparison to commercially available brushite- and apatite-based cements (chronOS(™) Inject and Norian(®) SRS(®), respectively), and in particular evaluate the diametral tensile strength and biaxial flexural strength of these cements in both wet and dry conditions for the first time. The cements׳ porosity and their compressive, diametral tensile and biaxial flexural strength were tested in wet (or moist) and dry conditions. The surface morphology was characterized by scanning electron microscopy. Phase composition was assessed with X-ray diffraction. It was found that the novel experimental cements showed better mechanical properties than the commercially available cements, in all loading scenarios. The highest com...
2009, Journal of Materials Science
In this review article, the state-of-the-art of calcium orthophosphate-based biocomposites and hybrid biomaterials suitable for biomedical applications is presented. This subject belongs to a rapidly expanding area of science and research, because these types of biomaterials offer many significant and exciting possibilities for hard tissue regeneration. Through the successful combinations of the desired properties of matrix materials with those of fillers (in such systems, calcium orthophosphates might play either role), innovative bone graft biomaterials can be designed. The review starts with an introduction to locate the reader. Further, general information on composites and hybrid materials including a brief description of their major constituents are presented. Various types of calcium orthophosphate-based bone-analogue biocomposites and hybrid biomaterials those are either already in use or being investigated for various biomedical applications are then extensively discussed. Many different formulations in terms of the material constituents, fabrication technologies, structural and bioactive properties, as well as both in vitro and in vivo characteristics have been already proposed. Among the others, the nano-structurally controlled biocomposites, those with nanosized calcium orthophosphates, biomimetically fabricated formulations with collagen, chitin and/or gelatin, as well as various functionally graded structures seem to be the most promising candidates for clinical applications. The specific advantages of using calcium orthophosphate-based biocomposites and hybrid biomaterials in the selected applications are highlighted. As the way from a laboratory to a hospital is a long one and the prospective biomedical candidates have to meet many different necessities, the review also examines the critical issues and scientific challenges that require further research and development.
2010, Biomaterials
A strong interest in use of ceramics for biomedical applications appeared in the late 1960's. Used initially as alternatives to metals in order to increase a biocompatibility of implants, bioceramics have become a diverse class of biomaterials, presently including three basic types: relatively bioinert ceramics, bioactive (or surface reactive) and bioresorbable ones. Furthermore, any type of bioceramics could be porous to provide tissue ingrowth. This review is devoted to bioceramics prepared from calcium orthophosphates, which belong to the categories of bioresorbable and bioactive compounds. During the past 30–40 years, there have been a number of major advances in this field. Namely, after the initial work on development of bioceramics that was tolerated in the physiological environment, emphasis was shifted towards the use of bioceramics that interacted with bones by forming a direct chemical bond. By the structural and compositional control, it became possible to choose whether the bioceramics of calcium orthophosphates was biologically stable once incorporated within the skeletal structure or whether it was resorbed over time. At the turn of the millennium, a new concept of calcium orthophosphate bioceramics, which is able to regenerate bone tissues, has been developed. Current biomedical applications of calcium orthophosphate bioceramics include replacements for hips, knees, teeth, tendons and ligaments, as well as repair for periodontal disease, maxillofacial reconstruction, augmentation and stabilization of the jawbone, spinal fusion and bone fillers after tumor surgery. Potential future applications of calcium orthophosphate bioceramics will include drug-delivery systems, as well as they will become effective carriers of growth factors, bioactive peptides and/or various types of cells for tissue engineering purposes.
2011, Ceramics International
2010, JOURNAL OF CERAMIC PROCESSING RESEARCH, Vol. 11, No. 3, pp. 367-371 (2010)
In this article 5-25 V% of a sol-gel bioglass fiber was incorporated into calcium phosphate bone cement to improve its mechanical properties. Compressive strength, work of fracture, elastic modulus and setting time of the cement were investigated as well as phase changes occurring during soaking the specimens in simulated body fluid (SBF). The cement microstructure was also observed by scanning electron microscope (SEM). The results showed that the compressive strength of the set cements without any fibers was 0.635 MPa which was optimally increased to 3.69 MPa by using 15% fibers and then decreased by further addition of the glass phase. In addition, both the work-of-fracture and elastic modulus of the cement were considerably increased when using the fibers in the cement composition. Setting time slightly decreased by using the fibers. A considerable content of the reactants in both fiber-free and fiber-containing cements were transformed to the apatite phase during soaking sample in SBF. http://jcpr.kbs-lab.co.kr/english/jcpr_journal_2010_3.htm
2014
2010, Journal of Functional Biomaterials
In the late 1960s, much interest was raised in regard to biomedical applications of various ceramic materials. A little bit later, such materials were named bioceramics. This review is limited to bioceramics prepared from calcium orthophosphates only, which belong to the categories of bioactive and bioresorbable compounds. There have been a number of important advances in this field during the past 30–40 years. Namely, by structural and compositional control, it became possible to choose whether calcium orthophosphate bioceramics were biologically stable once incorporated within the skeletal structure or whether they were resorbed over time. At the turn of the millennium, a new concept of calcium orthophosphate bioceramics—which is able to promote regeneration of bones—was developed. Presently, calcium orthophosphate bioceramics are available in the form of particulates, blocks, cements, coatings, customized designs for specific applications and as injectable composites in a polymer carrier. Current biomedical applications include artificial replacements for hips, knees, teeth, tendons and ligaments, as well as repair for periodontal disease, maxillofacial reconstruction, augmentation and stabilization of the jawbone, spinal fusion and bone fillers after tumor surgery. Exploratory studies demonstrate potential applications of calcium orthophosphate bioceramics as scaffolds, drug delivery systems, as well as carriers of growth factors, bioactive peptides and/or various types of cells for tissue engineering purposes.
2007, Journal of Biomedical Materials Research Part A
International Journal of Molecular Sciences
The current limitations of calcium phosphate cements (CPCs) used in the field of bone regeneration consist of their brittleness, low injectability, disintegration in body fluids and low biodegradability. Moreover, no method is currently available to measure the setting time of CPCs in correlation with the evolution of the setting reaction. The study proposes that it is possible to improve and tune the properties of CPCs via the addition of a thermosensitive, biodegradable, thixotropic copolymer based on poly(lactic acid), poly(glycolic acid) and poly(ethylene glycol) (PLGA–PEG–PLGA) which undergoes gelation under physiological conditions. The setting times of alpha-tricalcium phosphate (α-TCP) mixed with aqueous solutions of PLGA–PEG–PLGA determined by means of time-sweep curves revealed a lag phase during the dissolution of the α-TCP particles. The magnitude of the storage modulus at lag phase depends on the liquid to powder ratio, the copolymer concentration and temperature. A sha...