15,133 results match your criteria compressive strength

Micro-mechanical performance evaluation of expansive soil biotreated with indigenous bacteria using MICP method.

Sci Rep 2021 May 14;11(1):10324. Epub 2021 May 14.

Department of Civil Engineering, Indian Institute of Technology Indore, Indore, India.

This study explored the effect of indigenous bacteria present in the soil to stabilized swelling behavior and improving the mechanical property of expansive soil. The objective of the research is to investigate the effectiveness of the biostimulation microbial induced calcite precipitation (MICP) for controlling the swelling-shrinkage behavior and improving shear strength of expansive soil. An attempt was made to develop an effective procedure to culture the indigenous bacteria for treating clays with varying plasticity and improve their engineering behavior. Read More

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Skeletal microenvironment system utilising bovine bone scaffold co-cultured with human osteoblasts and osteoclast-like cells.

Exp Ther Med 2021 Jul 25;22(1):680. Epub 2021 Apr 25.

Department of Pharmacology, Faculty of Medicine, Pusat Perubatan Universiti Kebangsaan Malaysia, Cheras, Wilayah Persekutuan Kuala Lumpur 56000, Malaysia.

A three-dimensional bone cell culture system mimicking the skeletal system is useful for bone tissue engineering and as drug discovery platforms. The present study aimed to establish a three-dimensional skeletal culture system using native bovine bone scaffolds and human bone cells. Bovine bone scaffolds were cultured with human foetal osteoblasts 1. Read More

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Utilization of Spent FCC Catalyst as Fine Aggregate in Non-sintered Brick: Alkali Activation and Environmental Risk Assessment.

Front Chem 2021 26;9:674271. Epub 2021 Apr 26.

State Key Laboratory of Safety and Control for Chemicals, SINOPEC Research Institute of Safety Engineering, Qingdao, China.

This study focuses on the recycling of a spent fluid catalytic cracking (FCC) catalyst to produce catalyst-based non-sintered bricks (CN-bricks) for the recovery of its aluminosilicate components and the solidification of heavy metals. The effects of the content of cement (10-20%), the proportion of FCC (10-40%), and the type of an activator (NaOH/NaSiO/NaSO) on the performance of a CN-brick were investigated in terms of the mechanical strength and leaching behavior. The results show that an optimal binder system of 20% cement + NaSO could promote the compressive strength up to 42. Read More

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Structural performance of a climbing cactus: making the most of softness.

J R Soc Interface 2021 May 12;18(178):20210040. Epub 2021 May 12.

AMAP, Univ Montpellier, CIRAD, CNRS, INRAE, IRD, Montpellier, France.

Climbing plants must reach supports and navigate gaps to colonize trees. This requires a structural organization ensuring the rigidity of so-called 'searcher' stems. Cacti have succulent stems adapted for water storage in dry habitats. Read More

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Atraumatic femoral head necrosis: a biomechanical, histological and radiological examination compared to primary hip osteoarthritis.

Arch Orthop Trauma Surg 2021 May 10. Epub 2021 May 10.

Department of Orthopaedic, Trauma and Plastic Surgery, Leipzig University, Liebigstr. 20, 04103, Leipzig, Germany.

Introduction: Atraumatic necrosis of the femoral head (AFHN) is a common disease with an incidence of 5000-7000 middle-aged adults in Germany. There is no uniform consensus in the literature regarding the configuration of the bone in AFHN. The clinical picture of our patients varies from very hard bone, especially in idiopathic findings, and rather soft bone in cortisone-induced necrosis. Read More

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Plasticity characterization of certain Nigeria clay minerals for their application in ceramic water filters.

Sci Prog 2021 Apr-Jun;104(2):368504211012148

Department of Material Science and Engineering, African University of Science and Technology, Federal Capital Territory, Abuja, Nigeria.

Plasticity is an essential property of clay that determines its suitability for water filtration. There are no published works on the plastic behavior of clays from the study locations. The plastic behavior of seven Nigerian clays was examined using plasticity indices and compressive stress parameters in relation to chemical compositions and moisture content. Read More

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Production of bioconcrete with improved durability properties using Alkaliphilic Egyptian bacteria.

3 Biotech 2021 May 22;11(5):231. Epub 2021 Apr 22.

Department of Industrial Biotechnology, Genetic Engineering and Biotechnology Research Institute (GEBRI), University of Sadat City, Sadat, 22857/79 Egypt.

Microbial-based self-healing of concrete represents innovative technology for improving micro-crack sealing. Microbial bioactivity can induce calcite-precipitation in concrete, which seals micro-cracks. In this respect, two Egyptian bacterial isolates were selected and identified, as (Bs) and (Bm) using MALDI-TOF/MS-Biotyper. Read More

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Transparent, conductive cellulose hydrogel for flexible sensor and triboelectric nanogenerator at subzero temperature.

Carbohydr Polym 2021 Aug 15;265:118078. Epub 2021 Apr 15.

College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, China; Hubei Engineering Center of Natural Polymer-based Medical Materials, Wuhan University, Wuhan, 430072, China. Electronic address:

Herein, flexible, transparent and conductive cellulose hydrogels were directly fabricated by regenerating the chemically cross-linked cellulose in NaCl aqueous solution, without further treatment. NaCl played a dominant role on the mechanical, optical, conductive and anti-freezing properties of cellulose hydrogel, also endowed the hydrogel with safety. After optimization, the transparency, tensile strength, elongation at break and conductivity of the cellulose hydrogel reached 94 % at 550 nm, 5. Read More

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Preparation of a novel double crosslinked chitin aerogel via etherification with high strength.

Carbohydr Polym 2021 Aug 2;265:118014. Epub 2021 Apr 2.

Department of Mechanical and Industrial Engineering, Department of Materials Science and Engineering, Institute of Biomaterials and Biomedical Engineering, University of Toronto, 5 King's College Street, Toronto, Ontario, Canada. Electronic address:

In this study, we introduced a novel double crosslinked chitin aerogel via etherification with EGDE for mechanical reinforcement. Samples with different EGDE: chitin weight ratios from 0 to 1.5:1 were fabricated through chitin dissolution in KOH/urea aqueous solution, ethanol neutralization and washing, and supercritical CO drying. Read More

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Risk assessment of vertebral compressive fracture using bone mass index and strength predicted by computed tomography image based finite element analysis.

Clin Biomech (Bristol, Avon) 2021 Apr 23;85:105365. Epub 2021 Apr 23.

Inazawa Municipal Hospital, Department of Neurosurgery, Inazawa, Aichi 492-8510, Japan.

Background: A main purpose of osteoporosis diagnosis is to evaluate the bone fracture risk. Some bone mass indices evaluated using bone mineral density has been utilized clinically to assess the degree of osteoporosis. On the other hand, Computed tomography image based finite element analysis has been developed to evaluate bone strength of vertebral bodies. Read More

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Characteristics of soil salt crust formed by mixing calcium chloride with sodium sulfate and the possibility of inhibiting wind-sand flow.

Sci Rep 2021 May 7;11(1):9746. Epub 2021 May 7.

Institute of Arid Ecology and Environment, Xinjiang University, Urumqi, 830046, China.

Soil salt crust can change the structure of aeolian soil and improve its resistance to wind erosion. Four ions (Na, Ca, Cl, and SO) with high contents in aeolian soil were selected for a salt crust experiment. The experiment set a variety of gradients of soil salt contents and salt mixing ratios of NaSO and CaCl. Read More

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Interlocked Pins Increase Strength by a Lateral Spread of Load in Femoral Neck Fixation: a Cadaver Study.

Acta Chir Orthop Traumatol Cech 2021 ;88(2):144-152

Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Norway.

PURPOSE OF THE STUDY To improve the important torsional, bending and compressive stability in femoral neck fixation, locking plates have been the latest contribution. However, increased strength by restricted fracture motion may come at expense of an altered load distribution and failure patterns. Within locking plate technology, the important intermediate fracture compression may principally be achieved by multiple sliding screws passing through a sideplate fixed to the femur or connected to an interlocking plate not fixed to the femur laterally, sliding "en bloc" with the plate. Read More

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Comparison of three different screw trajectories in osteoporotic vertebrae: a biomechanical investigation.

BMC Musculoskelet Disord 2021 May 5;22(1):418. Epub 2021 May 5.

Department of Orthopedic Surgery, Traumatology and Plastic Surgery, Leipzig University, Liebigstraße 20, 04103, Leipzig, Germany.

Background: Pedicle screw insertion in osteoporotic patients is challenging. Achieving more screw-cortical bone purchase and invasiveness minimization, the cortical bone trajectory and the midline cortical techniques represent alternatives to traditional pedicle screws. This study compares the fatigue behavior and fixation strength of the cement-augmented traditional trajectory (TT), the cortical bone trajectory (CBT), and the midline cortical (MC). Read More

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Electrodialytic remediation of municipal solid waste incineration fly ash as pre-treatment before geopolymerisation with coal fly ash.

J Hazard Mater 2021 Jun 23;412:125220. Epub 2021 Jan 23.

Department of Civil Engineering, Technical University of Denmark, 2800 Lyngby, Denmark.

Municipal solid waste incineration (MSWI) fly ash is classified as hazardous waste and needs to be disposed of according to strict regulations. By disposal, valuable resources in the MSWI fly ash is lost, and other solutions are sought for. The effect of electrodialytic remediation (ED) as a pre-treatment for removing heavy metals from MSWI fly ash before using the treated ash in geopolymerization with coal fly ash was explored. Read More

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3D-printing-assisted fabrication of chitosan scaffolds from different sources and cross-linkers for dental tissue engineering.

Eur Cell Mater 2021 05 5;41:485-501. Epub 2021 May 5.

The aim of the present study was to fabricate and characterise chitosan scaffolds from animal and fungal sources, with or without gelatine as a co-polymer, and cross-linked to 3-glycidyloxyproply trimethoxysilane (GPTMS) or genipin for application in dental root tissue engineering. Chitosan-based scaffolds were prepared by the emulsion freeze-drying technique. Scanning electron microscopy (SEM) and nano-focus computed tomography (nano-CT) were used to characterise scaffold microstructure. Read More

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Enhanced mechanical and biological performances of CaO-MgO-SiO glass-ceramics via the modulation of glass and ceramic phases.

Mater Sci Eng C Mater Biol Appl 2021 May 26;124:112060. Epub 2021 Mar 26.

Research Center for Intelligent Medical Devices, Ming Chi University of Technology, New Taipei City 24301, Taiwan; International Ph.D. Program in Innovative Technology of Biomedical Engineering and Medical Devices, Ming Chi University of Technology, New Taipei City 24301, Taiwan; Department of Mechanical Engineering, Ming Chi University of Technology, New Taipei City 24301, Taiwan. Electronic address:

This work reports a new CaO-MgO-SiO (CMS) bioactive glass-ceramic, using ZrO as a nucleus to modulate the ratios of glass and ceramic phases as a function of sintering temperature. Mg-rich bioactive CMS glass-ceramics exhibit advantages regarding mechanical strength (flexural strength ~190 MPa and compressive strength ~555 MPa), in-vitro and in-vivo biocompatibilities, and bone ingrowth. The high mechanical strengths could be attributed to the CaMgSiO glass-ceramic and lower porosity. Read More

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A novel and injectable strontium-containing hydroxyapatite bone cement for bone substitution: A systematic evaluation.

Mater Sci Eng C Mater Biol Appl 2021 May 25;124:112052. Epub 2021 Mar 25.

Biomaterials Research and Test Center, Shanghai Ninth People's Hospital, Shanghai JiaoTong University, School of Medicine, College of Stomatology, Shanghai Jiao Tong University, National Center for Stomatology, National Clinical Research Center for Oral Diseases, Shanghai Key Laboratory of Stomatology, Shanghai, China. Electronic address:

Reconstruction of bone defects is still a challenge. In this study, we developed and systematically evaluated a novel injectable strontium-containing hydroxyapatite (Sr-HA) bone cement in which Sr-HA powder included 5% Sr and was mixed with a setting liquid that included 5% potassium citrate. This Sr-HA cement was mainly composed of HA and α-tricalcium phosphate (TCP) and exhibited favorable injectability (100%), setting times (the initial setting time was 240 s and the final setting time was 420 s), compressive strength (73. Read More

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Experimental Study on the Mechanical Properties and Compression Size Effect of Recycled Aggregate Concrete.

Materials (Basel) 2021 Apr 29;14(9). Epub 2021 Apr 29.

Department of Civil and Airport Engineering, College of Civilaviation (College of Flight), Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China.

To explore the basic mechanical properties and size effects of recycled aggregate concrete (RAC) with different substitution ratios of coarse recycled concrete aggregates (CRCAs) to replace natural coarse aggregates (NCA), the failure modes and mechanical parameters of RAC under different loading conditions including compression, splitting tensile resistance and direct shear were compared and analyzed. The conclusions drawn are as follows: the failure mechanisms of concrete with different substitution ratios of CRCAs are similar; with the increase in substitution ratio, the peak compressive stress and peak tensile stress of RAC decrease gradually, the splitting limit displacement decreases, and the splitting tensile modulus slightly increases; with the increase in the concrete cube's side length, the peak compressive stress of RAC declines gradually, but the integrity after compression is gradually improved; and the increase in the substitution ratio of the recycled aggregate reduces the impact of the size effect on the peak compressive stress of RAC. Furthermore, an influence equation of the coupling effect of the substitution ratio and size effect on the peak compressive stress of RAC was quantitatively established. Read More

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Mechanical Properties and Durability of Rubberized and Glass Powder Modified Rubberized Concrete for Whitetopping Structures.

Materials (Basel) 2021 Apr 29;14(9). Epub 2021 Apr 29.

Faculty of Civil Engineering and Architecture, Kaunas University of Technology, Studentų Str. 48, LT-51367 Kaunas, Lithuania.

This paper analyzes concrete fine aggregate (sand) modification by scrap tire rubber particles-fine crumb rubber (FCR) and coarse crumb rubber (CCR) of fraction 0/1 mm. Such rubberized concrete to get better bonding properties were modified by car-boxylated styrene butadiene rubber (SBR) latex and to gain the strength were modified by glass waste. The following tests-slump test, fresh concrete density, fresh concrete air content, compressive strength, flexural strength, fracture energy, freezing-thawing, porosity parameter, and scanning electron microscope-were conducted for rubberized concretes. Read More

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Experimental Evaluation of Shear Behavior of Stone Masonry Wall.

Materials (Basel) 2021 Apr 29;14(9). Epub 2021 Apr 29.

Department of Civil and Industrial Engineering-Structural Division, University of Pisa, 56122 Pisa, Italy.

The evaluation of the shear behavior of masonry walls is a first fundamental step for the assessment of existing masonry structures in seismic zones. However, due to the complexity of modelling experimental behavior and the wide variety of masonry types characterizing historical structures, the definition of masonry's mechanical behavior is still a critical issue. Since the possibility to perform in situ tests is very limited and often conflicting with the needs of preservation, the characterization of shear masonry behavior is generally based on reference values of mechanical properties provided in modern structural codes for recurrent masonry categories. Read More

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Study on the Strength Performance of Recycled Aggregate Concrete with Different Ages under Direct Shearing.

Materials (Basel) 2021 Apr 29;14(9). Epub 2021 Apr 29.

School of Civil and Architectural Engineering, Guangxi University of Science and Technology, Liuzhou 545006, China.

In order to study the mechanical properties of recycled aggregate concrete (RAC) at different ages, 264 standard cubes were designed to test its direct shear strength and cube compressive strength while considering the parameters of age and recycled aggregate replacement ratio. The failure pattern and load-displacement curve of specimens at direct shearing were obtained; the direct shear strength and residual shear strength were extracted from the load-displacement curves. Experimental results indicate that the influence of the replacement ratio for the front and side cracks of RAC is insignificant, with the former being straight and the latter relatively convoluted. Read More

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Flexural Performance and Toughness Characteristics of Geogrid-Reinforced Pervious Concrete with Different Aggregate Sizes.

Materials (Basel) 2021 Apr 29;14(9). Epub 2021 Apr 29.

School of Civil Engineering, Wuhan University, Wuhan 430072, China.

Pervious concrete is an environmentally friendly paving material to reduce surface runoff in urban construction. However, due to low flexural strength and cracking susceptibility caused by the high porosity, pervious concrete is only used in low-volume traffic roadways and parking lots for current service. This study investigated the permeability, strength, and flexural performance of pervious concrete with different coarse aggregate size, geogrid position, and geogrid layer number. Read More

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In-Situ Synthesis, Microstructure, and Mechanical Properties of TiB-Reinforced Fe-Cr-Mn-Al Steel Matrix Composites Prepared by Spark Plasma Sintering.

Materials (Basel) 2021 Apr 30;14(9). Epub 2021 Apr 30.

School of Automobile and Transportation Engineering, Guangdong Polytechnic Normal University, Guangzhou 510665, China.

In-situ synthesis, microstructure, and mechanical properties of four TiB-Reinforced Fe-Cr-Mn-Al Steel Matrix Composites have been researched in this work. The microstructure and phases of the prepared specimens have been characterized by using scanning electron microscopy (SEM), X-ray diffraction technique, and transmission electron microscopy (TEM). The sintered specimens consisted of FeAlCr, CrFeB-type boride, and TiB. Read More

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Mechanical Properties and Damage Evolution of Concrete Materials Considering Sulfate Attack.

Materials (Basel) 2021 Apr 30;14(9). Epub 2021 Apr 30.

School of Civil Engineering and Architecture, Anhui University of Science and Technology, Huainan 232001, China.

In order to study the durability of concrete materials subjected to sulfate attack, in a sulfate attack environment, a series of concrete tests considering different fly ash contents and erosion times were conducted. The mechanical properties and the micro-structure of concrete under sulfate attack were studied based on the following: uniaxial compressive strength test, split tensile test, ultrasonic impulse method, scanning electron microscopy (SEM) and X-ray diffraction (XRD). The mechanical properties were compressive strength, splitting tensile strength, and relative dynamic elastic modulus, respectively. Read More

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Mechanical and Thermal Properties of Synthetic Polypropylene Fiber-Reinforced Renewable Oil Palm Shell Lightweight Concrete.

Materials (Basel) 2021 Apr 30;14(9). Epub 2021 Apr 30.

Department of Civil Engineering, Lee Kong Chian Faculty of Engineering and Science, Universiti Tunku Abdul Rahman, Cheras, Kajang 43000, Malaysia.

Oil palm shell (OPS) is an agricultural solid waste from the extraction process of palm oil. All these wastes from industry pose serious disposal issues for the environment. This research aims to promote the replacement of conventional coarse aggregates with eco-friendly OPS aggregate which offers several advantages, such as being lightweight, renewable, and domestically available. Read More

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Biobased Polyurethane Composite Foams Reinforced with Plum Stones and Silanized Plum Stones.

Int J Mol Sci 2021 Apr 30;22(9). Epub 2021 Apr 30.

Faculty of Chemistry, Institute of Polymer & Dye Technology, Lodz University of Technology, 90-924 Lodz, Poland.

In the following study, ground plum stones and silanized ground plum stones were used as natural fillers for novel polyurethane (PUR) composite foams. The impact of 1, 2, and 5 wt.% of fillers on the cellular structure, foaming parameters, and mechanical, thermomechanical, and thermal properties of produced foams were assessed. Read More

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Development of eco-efficient lightweight self-compacting concrete with high volume of recycled EPS waste materials.

Environ Sci Pollut Res Int 2021 May 4. Epub 2021 May 4.

Civil Engineering Department, University of Halabja, Halabja, Kurdistan Region, Iraq.

Reusing the industrial waste materials is one of the main aims of sustainability and achieve the environmental protection. However, concrete is the main production for recycling waste materials and cleaning the climate. The utilization of self-consolidating lightweight concrete (SCLC) can achieve two important advantages of the structure self-weight reduction and improving workability. Read More

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Characterisation of key proteoglycans in the cranial cruciate ligaments (CCLs) from two dog breeds with different predispositions to CCL disease and rupture.

Vet J 2021 Jun 20;272:105657. Epub 2021 Mar 20.

Department of Musculoskeletal and Ageing Science, Institute of Life Course and Medical Sciences, University of Liverpool, William Duncan Building, 6 West Derby Street, Liverpool L7 8TX, UK; Small Animal Teaching Hospital, Leahurst Campus, School of Veterinary Science, University of Liverpool, Chester High Rd, Neston CH64 7TE, UK; The Medical Research Council Versus Arthritis Centre for Integrated Research into Musculoskeletal Ageing (CIMA), UK. Electronic address:

Cranial cruciate ligament disease and rupture (CCLD/R) is one of the most common orthopaedic conditions in dogs, eventually leading to osteoarthritis of the stifle joint. Certain dog breeds such as the Staffordshire bull terrier have an increased risk of developing CCLD/R. Previous studies into CCLD/R have found that glycosaminoglycan levels were elevated in cranial cruciate ligament (CCL) tissue from high-risk breeds when compared to the CCL from a low-risk breed to CCLD/R. Read More

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Prediction of the compressive strength of high-performance self-compacting concrete by an ultrasonic-rebound method based on a GA-BP neural network.

PLoS One 2021 3;16(5):e0250795. Epub 2021 May 3.

School of Civil Engineering, Hunan University, ChangSha, Hunan Province, China.

To address the problem of low accuracy and poor robustness of in situ testing of the compressive strength of high-performance self-compacting concrete (SCC), a genetic algorithm (GA)-optimized backpropagation neural network (BPNN) model was established to predict the compressive strength of SCC. Experiments based on two concrete nondestructive testing methods, i.e. Read More

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Hyaluronic acid facilitates bone repair effects of calcium phosphate cement by accelerating osteogenic expression.

Bioact Mater 2021 Nov 8;6(11):3801-3811. Epub 2021 Apr 8.

Center for Human Tissues and Organs Degeneration, Shenzhen Institutes of Advanced Technology, Chinese Academy of Science, Shenzhen, 518055, PR China.

Calcium phosphate cements (CPC) are widely anticipated to be an optimum bone repair substitute due to its satisfied biocompatibility and degradability, suitable to be used in minimally invasive treatment of bone defects. However the clinical application of CPC is still not satisfied by its poor cohesiveness and mechanical properties, in particular its osteoinductivity. Hyaluronic acid reinforced calcium phosphate cements (HA/CPC) showed extroadinary potential not only enhancing the compressive strength of the cements but also significantly increasing its osteoinductivity. Read More

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November 2021