Influence of Porosity on Fracture Toughness and Fracture Behavior of Antibiotic-Loaded PMMA Bone Cement

2021 ◽  
Author(s):  
Sunjung Kim ◽  
Caroline Baril ◽  
Shiva Rudraraju ◽  
Heidi-Lynn Ploeg
Keyword(s):  
Fracture Toughness ◽  
Crack Propagation ◽  
Bone Cement ◽  
Pore Size ◽  
Bending Strength ◽  
Volume Fraction ◽  
Total Joint Replacement ◽  
Experimental Results ◽  
Pmma Bone Cement ◽  
Cement Strength

Abstract Aseptic loosening is the most common reason for long-term revision of total joint replacement (TJR). Infection is the main reason for short-term revision of TJR. In our previous studies, experimental results showed that acrylic bone cement-loaded with antibiotics had a detrimental effect on cement strength such as bending strength, compressive strength, and fracture toughness. This result implied that the mechanical failure of antibiotic loaded bone cement was potentially related to porosity volume fraction. Hence, the objective of this study was to investigate the effect of pore size and distribution on bone cement fracture toughness. The effect of pores was analyzed using the extended Finite Element Method (X-FEM) method to model crack propagation and its modulation by pore sizes and locations. Numerically obtained load-displacement responses were compared to experimental results. We observed that crack propagation is affected by several pore parameters; as expected these include pore size and pore locations (pore-pore interactions) and are related to implicit pore-crack interactions. The experimental and numerical investigations presented in the current study contribute to a better understanding of the effect of pores on bone cement fracture toughness; key insights include the identification of a critical pore size for reduced fracture toughness, and relative insensitivity of crack propagation to stochastically distributed pore locations.

scholarly journals Alternative radiopacifiers for polymethyl methacrylate bone cements: Silane-treated anatase titanium dioxide and yttria-stabilised zirconium dioxide

2021 ◽  
Vol 35 (10) ◽  
pp. 1235-1252
Author(s):  
Wayne Nishio Ayre ◽  
Nicole Scully ◽  
Carole Elford ◽  
Bronwen AJ Evans ◽  
Wendy Rowe ◽  
...  
Keyword(s):  
Titanium Dioxide ◽  
Fatigue Crack ◽  
Crack Propagation ◽  
Bone Cement ◽  
Fatigue Crack Propagation ◽  
Zirconium Dioxide ◽  
Bending Strength ◽  
Cell Attachment ◽  
Pmma Bone Cement

Poly (methyl methacrylate) (PMMA) bone cement is widely used for anchoring joint arthroplasties. In cement brands approved for these procedures, micron-sized particles (usually barium sulphate, BaSO4) act as the radiopacifier. It has been postulated that these particles act as sites for crack initiation and subsequently cement fatigue. This study investigated whether alternative radiopacifiers, anatase titanium dioxide (TiO2) and yttria-stabilised zirconium dioxide (ZrO2), could improve the in vitro mechanical, fatigue crack propagation and biological properties of polymethyl methacrylate (PMMA) bone cement and whether their coating with a silane could further enhance cement performance. Cement samples containing 0, 5, 10, 15, 20 and 25%w/w TiO2 or ZrO2 and 10%w/w silane-treated TiO2 or ZrO2 were prepared and characterised in vitro in terms of radiopacity, compressive and bending strength, bending modulus, fatigue crack propagation, hydroxyapatite forming ability and MC3T3-E1 cell attachment and viability. Cement samples with greater than 10%w/w TiO2 and ZrO2 had a similar radiopacity to the control 10%w/w BaSO4 cement and commercial products. The addition of TiO2 and ZrO2 to bone cement reduced the bending strength and fracture toughness and increased fatigue crack propagation due to the formation of agglomerations and voids. Silane treating TiO2 reversed this effect, enhancing the dispersion and adhesion of particles to the PMMA matrix and resulted in improved mechanical properties and fatigue crack propagation resistance. Silane-treated TiO2 cements had increased nucleation of hydroxyapatite and MC3T3-E1 cell attachment in vitro, without significantly compromising cell viability. This research has demonstrated that 10%w/w silane-treated anatase TiO2 is a promising alternative radiopacifier for PMMA bone cement offering additional benefits over conventional BaSO4 radiopacifiers.

Microstructure and Mechanical Properties of Sintered Fibrous Monolith Cemented Carbide

2013 ◽  
Vol 815 ◽  
pp. 233-239
Author(s):  
Xue Quan Liu ◽  
Cun Guang Ding ◽  
Chang Hai Li ◽  
Yi Li ◽  
Li Xin Li ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Fracture Toughness ◽  
Crack Propagation ◽  
Fracture Energy ◽  
Bending Strength ◽  
Extrusion Process ◽  
Cemented Carbide ◽  
Cemented Carbides ◽  
Microstructure And Mechanical Properties

A fibrous monolith cemented carbide with WC-6Co as cell and WC-20Co as cell boundaries was produced through hot co-extrusion process in this paper. The density, hardness, bending strength and fracture toughness of the fibrous monolith cemented carbide were tested, and the fracture and crack propagation were observed by metalloscope and SEM. The results showed that the bending strength and fracture toughness of the fibrous monolith cemented carbides was remarkably improved 71.91% and 45.7% respectively, while the hardness was slightly decreased 1% compared with WC-6Co composites. It is the reason that the tougher shell WC-20Co with higher bending strength and fracture toughness can absorb more fracture energy, which can slow down and prevent the crack propagating from brittle core WC-6Co.

Fracture Characteristic of Mg-Al-Zn-Al2O3 Composites

2007 ◽  
Vol 353-358 ◽  
pp. 1378-1381
Author(s):  
Hao Ran Geng ◽  
Shou Ren Wang ◽  
Xin Ying Teng ◽  
Lin Hai Hui ◽  
Fu Song Xu
Keyword(s):  
Fracture Toughness ◽  
Metal Matrix ◽  
Bending Strength ◽  
Volume Fraction ◽  
Crack Nucleation ◽  
Spinel Phase ◽  
Interface Reaction ◽  
Matrix Alloy ◽  
Al2o3 Particle ◽  
Phase Phase

One kind of 3DNMMC with different volume fraction reinforcement phase was fabricated by pressureless technique. The bending strength and fracture toughness were tested by 3-P bending strength experiments. When the volume fraction of reinforcement phase phase was not in excess of 10%, composites had an improvement of bending strength and fracture toughness owing to relatively homogeneous Al2O3 particle distribution encircled by metal matrix and the occurrence of interface reaction product as MgAlO2 spinel phase. Much and smaller craters and dimples are observed in metal matrix alloy and limited ductility of composites causes the early failure of composites. With the increases of volume fraction of reinforcement phase phase, crack characteristic consist of crack nucleation, growth, coalescence and crack propagation became the main fracture failure mechanisms.

Unusual fracture behavior of nanoporous polymeric thin-films

2005 ◽  
Vol 880 ◽  
Author(s):  
Andrew V. Kearney ◽  
Reinhold H. Dauskardt ◽  
Carol E. Mohler ◽  
Michael E. Mills
Keyword(s):  
Fracture Toughness ◽  
Pore Size ◽  
Fracture Resistance ◽  
Fracture Behavior ◽  
Volume Fraction ◽  
Porous Solids ◽  
Void Size ◽  
Polymeric Thin Films ◽  
Arylene Ether ◽  
Ductile Polymer

AbstractWe present surprising evidence that the fracture resistance of porous forms of poly(arylene) ether (PAE) films exhibit increasing fracture resistance with increasing porosity. Such behavior is in stark contrast to the fracture toughness of porous solids, which typically decrease markedly with increasing porosity. A fracture mechanics based model is presented to rationalize the increase in fracture toughness of the voided polymer film and explain the behavior in terms of the pore size and volume fraction. It is shown that a certain dependence of pore size and volume fraction is required to increase rather than decrease the fracture resistance. The research has implications for the optimum void size and volume fraction needed to enhance the fracture resistance of porous ductile polymer films.

scholarly journals Effects of HfC Particles on Crack Initiation and Propagation Behavior of WC/Co Composites

2019 ◽  
Vol 37 (3) ◽  
pp. 628-635
Author(s):  
Xinyu Yan ◽  
Shouren Wang ◽  
Daosheng Wen ◽  
Gaoqi Wang ◽  
Wentao Liu
Keyword(s):  
Fracture Toughness ◽  
Crack Propagation ◽  
Bending Strength ◽  
Crack Tip ◽  
Crack Deflection ◽  
Simulation Software ◽  
Homogeneous Distribution ◽  
The Matrix ◽  
Crack Pinning ◽  
Crack Bifurcation

Tungsten carbide composites were prepared by cold-pressing and hot-pressing sintering; fracture toughness and bending strength of the specimens were tested. The microstructures of HfC/WC/Co composites were observed with the SEM. The mathematical models were established to investigate the relationship between stress intensity factors of crack straight-through, crack deflection, and crack bifurcation with crack length, based on the crack propagation energy release rate. The simulation software ABAQUS was used to verify the four crack propagation methods of crack straight-through, crack deflection, crack bifurcation and crack pinning. The simulation results show that adding appropriate amount of HfC can effectively improve the fracture toughness and bending strength of the composites. The homogeneous distribution of HfC and Co in the matrix has a significant effect on the improvement of the strength and toughness of the composites, and the improvement mechanism is to disperse or transfer the stress at the crack tip to HfC by crack deflection, crack bifurcation, crack pinning, transcrystalline fracture, etc. As a result, the stress concentration at the crack tip in the matrix is reduced, and the toughness of the composites is improved.

scholarly journals Advanced G-MPS-PMMA Bone Cements: Influence of Graphene Silanisation on Fatigue Performance, Thermal Properties and Biocompatibility

Nanomaterials ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 139
Author(s):  
Eva Paz ◽  
Yolanda Ballesteros ◽  
Juana Abenojar ◽  
Nicholas Dunne ◽  
Juan C. del Real
Keyword(s):  
Thermal Properties ◽  
Bone Cement ◽  
Bending Strength ◽  
Mechanical Performance ◽  
Fatigue Loading ◽  
Negative Influence ◽  
Fatigue Performance ◽  
Bone Cements ◽  
Bending Modulus ◽  
Pmma Bone Cement

The incorporation of well-dispersed graphene (G) powder to polymethyl methacrylate (PMMA) bone cement has been demonstrated as a promising solution to improving its mechanical performance. However, two crucial aspects limit the effectiveness of G as a reinforcing agent: (1) the poor dispersion and (2) the lack of strong interfacial bonds between G and the matrix of the bone cement. This work reports a successful functionalisation route to promote the homogenous dispersion of G via silanisation using 3-methacryloxypropyltrimethoxy silane (MPS). Furthermore, the effects of the silanisation on the mechanical, thermal and biocompatibility properties of bone cements are presented. In comparison with unsilanised G, the incorporation of silanised G (G_MPS1 and G_MPS2) increased the bending strength by 17%, bending modulus by 15% and deflection at failure by 17%. The most impressive results were obtained for the mechanical properties under fatigue loading, where the incorporation of G_MPS doubled the Fatigue Performance Index (I) value of unsilanised G-bone cement—meaning a 900% increase over the I value of the cement without G. Additionally, to ensure that the silanisation did not have a negative influence on other fundamental properties of bone cement, it was demonstrated that the thermal properties and biocompatibility were not negatively impacted—allowing its potential clinical progression.

Sign in / Sign up

Export Citation Format

Share Document