Journal articles on the topic 'PMMA cement'
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1
Tang, Zheng Hai, Xiao Wen Wang, Lin Pan, Yan Wen Hu, Yang Wu, Jie Ying Zhang, Shuai Cui, Ji Yao Kang, and Jin Tian Tang. "Preparation and Characterization of PMMA-Based Cements Containing Magnetic Nanoparticles for the Magnetic Hyperthermia." Advanced Materials Research 647 (January 2013): 155–59. http://dx.doi.org/10.4028/www.scientific.net/amr.647.155.
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Three types of polymethylmethacrylate(PMMA)-based cements containing magnetic (Fe3O4) particles were developed and their properties were evaluated. The commercial available PMMA cement (PMMAc) was used as a control material. The setting time of the cement extended while the compressive strength of the samples decreased with increasing Fe3O4 content. There was no obvious difference in peak temperature between the cements during the setting reaction. The cement with 10 wt% Fe3O4 in an alternating magnetic field (AMF) of 125 Gs and cement with 20 wt% Fe3O4 in an AMF of 100 Gs could generate enough heat for the therapeutic hyperthermia of bone metastasis.
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Cui, Xu, Chengcheng Huang, Meng Zhang, Changshun Ruan, Songlin Peng, Li Li, Wenlong Liu, et al. "Enhanced osteointegration of poly(methylmethacrylate) bone cements by incorporating strontium-containing borate bioactive glass." Journal of The Royal Society Interface 14, no. 131 (June 2017): 20161057. http://dx.doi.org/10.1098/rsif.2016.1057.
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Although poly(methylmethacrylate) (PMMA) cements are widely used in orthopaedics, they have numerous drawbacks. This study aimed to improve their bioactivity and osseointegration by incorporating strontium-containing borate bioactive glass (SrBG) as the reinforcement phase and bioactive filler of PMMA cement. The prepared SrBG/PMMA composite cements showed significantly decreased polymerization temperature when compared with PMMA and retained properties of appropriate setting time and high mechanical strength. The bioactivity of SrBG/PMMA composite cements was confirmed in vitro , evidenced by ion release (Ca, P, B and Sr) from SrBG particles. The cellular responses of MC3T3-E1 cells in vitro demonstrated that SrBG incorporation could promote adhesion, migration, proliferation and collagen secretion of cells. Furthermore, our in vivo investigation revealed that SrBG/PMMA composite cements presented better osseointegration than PMMA bone cement. SrBG in the composite cement could stimulate new-bone formation around the interface between the composite cement and host bone at eight and 12 weeks post-implantation, whereas PMMA bone cement only stimulated development of an intervening connective tissue layer. Consequently, the SrBG/PMMA composite cement may be a better alternative to PMMA cement in clinical applications and has promising orthopaedic applications by minimal invasive surgery.
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Saruta, Juri, Ryotaro Ozawa, Kosuke Hamajima, Makiko Saita, Nobuaki Sato, Manabu Ishijima, Hiroaki Kitajima, and Takahiro Ogawa. "Prolonged Post-Polymerization Biocompatibility of Polymethylmethacrylate-Tri-n-Butylborane (PMMA-TBB) Bone Cement." Materials 14, no. 5 (March 8, 2021): 1289. http://dx.doi.org/10.3390/ma14051289.
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Polymethylmethacrylate (PMMA)-based acrylic bone cement is commonly used to fix bone and metallic implants in orthopedic procedures. The polymerization initiator tri-n-butylborane (TBB) has been reported to significantly reduce the cytotoxicity of PMMA-based bone cement compared to benzoyl peroxide (BPO). However, it is unknown whether this benefit is temporary or long-lasting, which is important to establish given that bone cement is expected to remain in situ permanently. Here, we compared the biocompatibility of PMMA-TBB and PMMA-BPO bone cements over several days. Rat femur-derived osteoblasts were seeded onto two commercially-available PMMA-BPO bone cements and experimental PMMA-TBB polymerized for one day, three days, or seven days. Significantly more cells attached to PMMA-TBB bone cement during the initial stages of culture than on both PMMA-BPO cements, regardless of the age of the materials. Proliferative activity and differentiation markers including alkaline phosphatase production, calcium deposition, and osteogenic gene expression were consistently and considerably higher in cells grown on PMMA-TBB than on PMMA-BPO, regardless of cement age. Although osteoblastic phenotypes were more favorable on older specimens for all three cement types, biocompatibility increased between three-day-old and seven-day-old PMMA-BPO specimens, and between one-day-old and three-day-old PMMA-TBB specimens. PMMA-BPO materials produced more free radicals than PMMA-TBB regardless of the age of the material. These data suggest that PMMA-TBB maintains superior biocompatibility over PMMA-BPO bone cements over prolonged periods of at least seven days post-polymerization. This superior biocompatibility can be ascribed to both low baseline cytotoxicity and a further rapid reduction in cytotoxicity, representing a new biological advantage of PMMA-TBB as a novel bone cement material.
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Komatsu, Keiji, Kosuke Hamajima, Ryotaro Ozawa, Hiroaki Kitajima, Takanori Matsuura, and Takahiro Ogawa. "Novel Tuning of PMMA Orthopedic Bone Cement Using TBB Initiator: Effect of Bone Cement Extracts on Bioactivity of Osteoblasts and Osteoclasts." Cells 11, no. 24 (December 10, 2022): 3999. http://dx.doi.org/10.3390/cells11243999.
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Bone cement containing benzoyl peroxide (BPO) as a polymerization initiator are commonly used to fix orthopedic metal implants. However, toxic complications caused by bone cement are a clinically significant problem. Poly (methyl methacrylate) tri-n-butylborane (PMMA-TBB), a newly developed material containing TBB as a polymerization initiator, was found to be more biocompatible than conventional PMMA-BPO bone cements due to reduced free radical generation during polymerization. However, free radicals might not be the only determinant of cytotoxicity. Here, we evaluated the response and functional phenotypes of cells exposed to extracts derived from different bone cements. Bone cement extracts were prepared from two commercial PMMA-BPO cements and an experimental PMMA-TBB. Rat bone marrow-derived osteoblasts and osteoclasts were cultured in a medium supplemented with bone cement extracts. More osteoblasts survived and attached to the culture dish with PMMA-TBB extract than in the culture with PMMA-BPO extracts. Osteoblast proliferation and differentiation were higher in the culture with PMMA-TBB extract. The number of TRAP-positive multinucleated cells was significantly lower in the culture with PMMA-TBB extract. There was no difference in osteoclast-related gene expression in response to different bone cement extracts. In conclusion, PMMA-TBB extract was less toxic to osteoblasts than PMMA-BPO extracts. Although extracts from the different cement types did not affect osteoclast function, PMMA-TBB extract seemed to reduce osteoclastogenesis, a possible further advantage of PMMA-TBB cement. These implied that the reduced radical generation during polymerization is not the only determinant for the improved biocompatibility of PMMA-TBB and that the post-polymerization chemical elution may also be important.
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Liu, Xing, Can Cheng, Xu Peng, Hong Xiao, Chengrui Guo, Xu Wang, Li Li, and Xixun Yu. "A promising material for bone repair: PMMA bone cement modified by dopamine-coated strontium-doped calcium polyphosphate particles." Royal Society Open Science 6, no. 10 (October 2019): 191028. http://dx.doi.org/10.1098/rsos.191028.
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Polymethyl methacrylate (PMMA) bone cement has been widely used in clinics as bone repair materials for its excellent mechanical properties and good injection properties. However, it also has defects such as poor biological performance, high temperature, and the monomer has certain toxicity. Our study tried to modify the PMMA bone cement by doping with various particle weight fractions (5, 10 and 15%) of SCPP particles and polydopamine-coated SCPP particles (D/SCPP) to overcome its clinical application disadvantages. Our study showed that all results of physical properties of samples are in accordance with ISO 5833. The 15% D/SCPP/PMMA composite bone cement had much better biocompatibility compared with pure PMMA bone cement and SCPP/PMMA composite bone cement due to the best cell growth-promoting mineralization deposition on the surface of 15% D/SCPP/PMMA composite bone cements and Sr 2+ released from SCPP particles. Our research also revealed that the reaction temperature was found to be reduced with an increase in doped particles after incorporating the particles into composite bone cements. The novel PMMA bone cements modified by D/SCPP particles are promising materials for bone repair.
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Goto, Koji, Masami Hashimoto, Shunsuke Fujibayashi, Tadashi Kokubo, and Takashi Nakamura. "New Bioactive Bone Cement Containing Nano-Sized Titania Particles." Key Engineering Materials 284-286 (April 2005): 97–100. http://dx.doi.org/10.4028/www.scientific.net/kem.284-286.97.
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Two types of new bioactive polymethylmethacrylate (PMMA)-based bone cements containing nano−sized titania (TiO2) particles were prepared and evaluated to assess the effect of TiO2 content on their mechanical properties and osteoconductivity. We prepared two types of bioactive bone cement, ST50c and ST60c, which contained 50 wt% silanized TiO2 and 60 wt% silanized TiO2, respectively. Commercially available PMMA cement (PMMAc) was used as a control. The cements were inserted into rat tibiae and solidified in situ. After 6 and 12 weeks, they were taken out for evaluation of osteoconductivity by scanning electron microscopy (SEM), contact microradiography (CMR) and Giemsa surface staining. SEM revealed that ST60c and ST50c apposed to bone directly while PMMAc did not. The affinity index of ST60c was significantly higher than for the other cements at each time interval. The results showed that ST60c was a promising material, but its mechanical strength should be improved before application in prosthesis fixation.
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Bistolfi, Ferracini, Albanese, Vernè, and Miola. "PMMA-Based Bone Cements and the Problem of Joint Arthroplasty Infections: Status and New Perspectives." Materials 12, no. 23 (December 2, 2019): 4002. http://dx.doi.org/10.3390/ma12234002.
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Polymethyl methacrylate (PMMA)-based bone cement is a biomaterial that has been used over the last 50 years to stabilize hip and knee implants or as a bone filler. Although PMMA-based bone cement is widely used and allows a fast-primary fixation to the bone, it does not guarantee a mechanically and biologically stable interface with bone, and most of all it is prone to bacteria adhesion and infection development. In the 1970s, antibiotic-loaded bone cements were introduced to reduce the infection rate in arthroplasty; however, the efficiency of antibiotic-containing bone cement is still a debated issue. For these reasons, in recent years, the scientific community has investigated new approaches to impart antibacterial properties to PMMA bone cement. The aim of this review is to summarize the current status regarding antibiotic-loaded PMMA-based bone cements, fill the gap regarding the lack of data on antibacterial bone cement, and explore the progress of antibacterial bone cement formulations, focusing attention on the new perspectives. In particular, this review highlights the innovative study of composite bone cements containing inorganic antibacterial and bioactive phases, which are a fascinating alternative that can impart both osteointegration and antibacterial properties to PMMA-based bone cement.
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Wang, Tong Fu, Sheng Peng Ding, and Hai Chuan Cao. "Determinate the Fracture Toughness of PMMA Cement." Advanced Materials Research 1030-1032 (September 2014): 758–61. http://dx.doi.org/10.4028/www.scientific.net/amr.1030-1032.758.
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In this paper, adding multiwalled carbon nanotubes (MWCNTs) to the polymethylmethacrylate-based (PMMA) bone cements as a way of reinforcement were prepared, and the structure was investigated. The aim of this study was to confirmed the transverse-direction fracture toughness (KIv) in bone cement. TheKIvof PMMA cement and PMMA/MWNCTs cement were determined to be 1.32±0.1 MPa m1/2and 1.96±0.1 MPa m1/2, respectively.
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Lewin, Susanne, Peter Försth, and Cecilia Persson. "Low-Modulus PMMA Has the Potential to Reduce Stresses on Endplates after Cement Discoplasty." Journal of Functional Biomaterials 13, no. 1 (February 4, 2022): 18. http://dx.doi.org/10.3390/jfb13010018.
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Cement discoplasty has been developed to treat patients with advanced intervertebral disc degeneration. In discoplasty, poly(methylmethacrylate) (PMMA) bone cement is injected into the disc, leading to reduced pain and certain spinal alignment correction. Standard PMMA-cements have much higher elastic modulus than the surrounding vertebral bone, which may lead to a propensity for adjacent fractures. A PMMA-cement with lower modulus might be biomechanically beneficial. In this study, PMMA-cements with lower modulus were obtained using previously established methods. A commercial PMMA-cement (V-steady®, G21 srl) was used as control, and as base cement. The low-modulus PMMA-cements were modified by 12 vol% (LA12), 16 vol% (LA16) and 20 vol% (LA20) linoleic acid (LA). After storage in 37 °C PBS from 24 h up to 8 weeks, specimens were tested in compression to obtain the material properties. A lower E-modulus was obtained with increasing amount of LA. However, with storage time, the E-modulus increased. Standard and low-modulus PMMA discoplasty were compared in a previously developed and validated computational lumbar spine model. All discoplasty models showed the same trend, namely a substantial reduction in range of motion (ROM), compared to the healthy model. The V-steady model had the largest ROM-reduction (77%), and the LA20 model had the smallest (45%). The average stress at the endplate was higher for all discoplasty models than for the healthy model, but the stresses were reduced for cements with higher amounts of LA. The study indicates that low-modulus PMMA is promising for discoplasty from a mechanical viewpoint. However, validation experiments are needed, and the clinical setting needs to be further considered.
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Funk, Grahmm August, Elizabeth M. Menuey, William P. Ensminger, Kathleen V. Kilway, and Terence E. McIff. "Elution of rifampin and vancomycin from a weight-bearing silorane-based bone cement." Bone & Joint Research 10, no. 4 (April 1, 2021): 277–84. http://dx.doi.org/10.1302/2046-3758.104.bjr-2020-0430.r1.
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Aims Poly(methyl methacrylate) (PMMA)-based bone cements are the industry standard in orthopaedics. PMMA cement has inherent disadvantages, which has led to the development and evaluation of a novel silorane-based biomaterial (SBB) for use as an orthopaedic cement. In this study we test both elution and mechanical properties of both PMMA and SBB, with and without antibiotic loading. Methods For each cement (PMMA or SBB), three formulations were prepared (rifampin-added, vancomycin-added, and control) and made into pellets (6 mm × 12 mm) for testing. Antibiotic elution into phosphate-buffered saline was measured over 14 days. Compressive strength and modulus of all cement pellets were tested over 14 days. Results The SBB cement was able to deliver rifampin over 14 days, while PMMA was unable to do so. SBB released more vancomycin overall than did PMMA. The mechanical properties of PMMA were significantly reduced upon rifampin incorporation, while there was no effect to the SBB cement. Vancomycin incorporation had no effect on the strength of either cement. Conclusion SBB was found to be superior in terms of rifampin and vancomycin elution. Additionally, the incorporation of these antibiotics into SBB did not reduce the strength of the resultant SBB cement composite whereas rifampin substantially attenuates the strength of PMMA. Thus, SBB emerges as a potential weight-bearing alternative to PMMA for the local delivery of antibiotics. Cite this article: Bone Joint Res 2021;10(4):277–284.
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Hamajima, Kosuke, Ryotaro Ozawa, Juri Saruta, Makiko Saita, Hiroaki Kitajima, Samira Rahim Taleghani, Dan Usami, et al. "The Effect of TBB, as an Initiator, on the Biological Compatibility of PMMA/MMA Bone Cement." International Journal of Molecular Sciences 21, no. 11 (June 4, 2020): 4016. http://dx.doi.org/10.3390/ijms21114016.
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Acrylic bone cement is widely used in orthopedic surgery for treating various conditions of the bone and joints. Bone cement consists of methyl methacrylate (MMA), polymethyl methacrylate (PMMA), and benzoyl peroxide (BPO), functioning as a liquid monomer, solid phase, and polymerization initiator, respectively. However, cell and tissue toxicity caused by bone cement has been a concern. This study aimed to determine the effect of tri-n-butyl borane (TBB) as an initiator on the biocompatibility of bone cement. Rat spine bone marrow-derived osteoblasts were cultured on two commercially available PMMA-BPO bone cements and a PMMA-TBB experimental material. After a 24-h incubation, more cells survived on PMMA-TBB than on PMMA-BPO. Cytomorphometry showed that the area of cell spread was greater on PMMA-TBB than on PMMA-BPO. Analysis of alkaline phosphatase activity, gene expression, and matrix mineralization showed that the osteoblastic differentiation was substantially advanced on the PMMA-TBB. Electron spin resonance (ESR) spectroscopy revealed that polymerization radical production within the PMMA-TBB was 1/15–1/20 of that within the PMMA-BPO. Thus, the use of TBB as an initiator, improved the biocompatibility and physicochemical properties of the PMMA-based material.
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Robu, Alina, Aurora Antoniac, Robert Ciocoiu, Elena Grosu, Julietta V. Rau, Marco Fosca, Ivan I. Krasnyuk, et al. "Effect of the Antimicrobial Agents Peppermint Essential Oil and Silver Nanoparticles on Bone Cement Properties." Biomimetics 7, no. 3 (September 17, 2022): 137. http://dx.doi.org/10.3390/biomimetics7030137.
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The main problems directly linked with the use of PMMA bone cements in orthopedic surgery are the improper mechanical bond between cement and bone and the absence of antimicrobial properties. Recently, more research has been devoted to new bone cement with antimicrobial properties using mainly antibiotics or other innovative materials with antimicrobial properties. In this paper, we developed modified PMMA bone cement with antimicrobial properties proposing some experimental antimicrobial agents consisting of silver nanoparticles incorporated in ceramic glass and hydroxyapatite impregnated with peppermint oil. The impact of the addition of antimicrobial agents on the structure, mechanical properties, and biocompatibility of new PMMA bone cements was quantified. It has been shown that the addition of antimicrobial agents improves the flexural strength of the traditional PMMA bone cement, while the yield strength values show a decrease, most likely because this agent acts as a discontinuity inside the material rather than as a reinforcing agent. In the case of all samples, the addition of antimicrobial agents had no significant influence on the thermal stability. The new PMMA bone cement showed good biocompatibility and the possibility of osteoblast proliferation (MTT test) along with a low level of cytotoxicity (LDH test).
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Minari, C., M. Baleanil, L. Cristofolini, and F. Baruffaldi. "The effect on the fatigue strength of bone cement of adding sodium fluoride." Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine 215, no. 2 (February 1, 2001): 251–53. http://dx.doi.org/10.1243/0954411011533643.
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New bone cements that include several additives are currently being investigated and tested. One such additive is sodium fluoride (NaF), which promotes bone formation, facilitating implant integration and success. The influence of NaF on the fatigue performance of the cement as used in biomedical applications was tested in this paper. In fact fatigue failure of the cement mantle is a major factor limiting the longevity of a cemented implant. An experimental bone cement with added NaF (12wt%) was investigated. The fatigue strength of the novel bone cement was evaluated in comparison with the cement without additives; fatigue tests were conducted according to current standards. The load levels were arranged based on a validated, statistically based optimization algorithm. The curve of stress against number of load cycles and the endurance limit were obtained and compared for both formulations. The results showed that the addition of NaF (12 wt %) to polymethylmethacrylate (PMMA) bone cement does not affect the fatigue resistance of the material. Sodium fluoride can safely be added to the bone cement without altering the fatigue performance of the PMMA bone cement.
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Wekwejt, M., S. Chen, B. Kaczmarek-Szczepańska, M. Nadolska, K. Łukowicz, A. Pałubicka, A. Michno, A. M. Osyczka, M. Michálek, and A. Zieliński. "Nanosilver-loaded PMMA bone cement doped with different bioactive glasses – evaluation of cytocompatibility, antibacterial activity, and mechanical properties." Biomaterials Science 9, no. 8 (2021): 3112–26. http://dx.doi.org/10.1039/d1bm00079a.
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Cavalu, Simona. "Acrylic Bone Cements: New Insight and Future Perspective." Key Engineering Materials 745 (July 2017): 39–49. http://dx.doi.org/10.4028/www.scientific.net/kem.745.39.
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The history of acrylic bone cement comprise a long period of time, Sir John Charnley being considered the founder of modern artificial joint replacement, as he started to develop the cementing in the late 1950s. Acrylic bone cements (ACB) are polymer-ceramic composites based on polymethyl metacrylate (PMMA), widely used in orthopaedics as suture materials and fixation devices. The main features of these materials are: 1) biocompatibility and ability to support new bone growth (osteoconductive) and 2) bioactivity (ability to form a calcium phosphate layer on its surface). The main function of the cement is to serve as interfacial phase between the high modulus metallic implant and the bone, thereby assisting to transfer and distribute loads. During years of follow up, cemented prosthesis with acrylic bone cements (ABC) demonstrated a good primary fixation and load distribution between implant and bone, along with the advantage of fast recovery of the patient. However, several problems are still persisting, as the orthopedic acrylic bone cements have to meet several medical requirements, such as low values of maximum cure temperature in order to avoid thermal necrosis of the bone tissue during the setting time, appropriate setting time (so that cement does not cure too fast or too slowly) and high values of compressive strength in order to withstand the compressive loads involved by normal daily activities. Generally, the improvement mechanical properties can be realized in three directions: 1) by searching alternative material to PMMA acrylic bone cements; 2) chemical modification of PMMA; and 3) the reinforcement of PMMA by adding different bioactive particles, antimicrobials, vitamins. The aim of this rewiew is to explore the development of bone cements in the last decade, to highlight the role of bone cement additives with respect to mechanical properties and limitations of polymethylmethacrylate in orthopaedic surgery. The behavior of antibiotic-loaded bone cement is discussed, compared with other alternative additives including nanofillers, together with areas of research that are now open to explore new insights and applications of this well known biomaterial.
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Puska, Mervi, Ari-Pekka Forsback, Antti Yli-Urpo, Jukka Seppälä, and Pekka K. Vallittu. "Biomineralization of Glass Fibre Reinforced Porous Acrylic Bone Cement." Key Engineering Materials 330-332 (February 2007): 815–18. http://dx.doi.org/10.4028/www.scientific.net/kem.330-332.815.
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Acrylic bone cements are used to fix joint replacements to bone. The main substance in acrylic bone cement is biologically inert poly(methylmethacrylate), PMMA. The dense PMMA polymer structure of cement does not allow bone ingrowth into cement. Therefore, the main focus of our studies is to modify acrylic bone cement in order to improve its biological properties e.g., by creating porosity in the cement matrix. The porous structure is in situ created using pore-generating filler (i.e., 20 wt% of an experimental biodegradable polyamide) that is incorporated in acrylic bone cement. The aim of this in vitro study was to investigate the biomineralization of acrylic bone cement modified using an experimental biodegradable polyamide.
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Hashimoto, Masami, Hiroaki Takadama, Mineo Mizuno, Tadashi Kokubo, Koji Goto, and Takashi Nakamura. "Bioactive PMMA-Based Cement Incorporated with Nano-Sized Rutile Particles." Key Engineering Materials 309-311 (May 2006): 797–800. http://dx.doi.org/10.4028/www.scientific.net/kem.309-311.797.
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Bioactive bone cement with mechanical properties higher than that of commercial polymethylmethacrylate (PMMA) bone cement are strongly desired to be developed. In the present study, PMMA-based cement incorporated with nano-sized rutile particles was prepared. The PMMA-based cement (rutile content was 50 wt%) shows the compressive strength (136 MPa) higher than that of commercial PMMA bone cement (88 MPa). The hardened cement formed apatite on the surface in a simulated body fluid within 3 days. Therefore, this PMMA-based cement incorporated with rutile particles might be useful as cement for fixation of prostheses as well as self-setting bone substitutes, because of its high apatite forming ability and mechanical strength.
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Harper, E. J. "Bioactive bone cements." Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine 212, no. 2 (February 1, 1998): 113–20. http://dx.doi.org/10.1243/0954411981533881.
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Poly (methylmethacrylate) (PMMA) bone cement, used to fix implants into the bone, produces good surgical results if used correctly. However, prostheses do eventually become loose and the breakdown of the cement mantle is a factor in this failure. Limitations of PMMA cement, which lead to problems with the fixation of the implant, include its mechanical characteristics and its influence upon surrounding bone, associated with the polymerization reaction. A bioactive bone cement is particularly designed to produce a better interface between the cement and bone. However, an improvement in mechanical properties, especially fatigue, creep and fracture toughness, are an added necessary requirement to increase the lifetime of a cemented implant. The development of a bioactive cement has been conducted mainly in two ways; firstly, to improve existing PMMA cement by the addition of various bioactive agents and secondly, to design an alternative matrix for the bioactive material to be combined with. The most promising investigations which have been conducted, along with their relative benefits and drawbacks, are discussed.
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Rosenstein, A., W. MacDonald, A. Iliadis, and P. McLardy-Smith. "Revision of Cemented Fixation and Cement—Bone Interface Strength." Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine 206, no. 1 (March 1992): 47–49. http://dx.doi.org/10.1243/pime_proc_1992_206_261_02.
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Interfacial shear strength between poly(methyl methacrylate) (PMMA) bone cement and cancellous bone was measured in bone samples from human proximal femora. Samples were prepared with fresh cement-bone, fresh cement inside a mantle of existing cement and with fresh cement-revised bone surfaces. Push-out tests to measure shear strength caused failure only at bone-cement interfaces; revised bone interfaces were 30 per cent weaker (P < 0.02) than primary interfaces. The clinical relevance is that revision of cemented joint arthroplasties may necessitate removal of components with sound cement-bone fixation. The practice of removing all traces of PMMA cement may not yield the optimal fixation; adhesion of fresh cement to freshly prepared surfaces of the existing cement might also be considered where circumstances are favourable.
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Baleani, M., L. Cristofolini, C. Minari, and A. Toni. "Fatigue strength of PMMA bone cement mixed with gentamicin and barium sulphate vs pure PMMA." Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine 217, no. 1 (January 1, 2003): 9–12. http://dx.doi.org/10.1243/095441103762597683.
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Barium sulphate is added to polymethylmethacrylate (PMMA) bone cement as a radio-pacifier. Gentamicin is an antibiotic added to bone cement to treat or prevent infection in arthroplasty. This study investigated the combined effect of barium sulphate and gentamicin sulphate on the fatigue strength of PMMA bone cement. Three different formulations were studied: pure PMMA, PMMA with barium sulphate added and PMMA with barium sulphate and gentamicin sulphate added. Before testing all specimens were stored in water at 37°C for at least 15 days to season the PMMA and to elute the antibiotic. Fatigue tests were performed following a previously validated procedure. The slope part of the Wöhler diagram was obtained and a rough endurance limit was estimated for all three formulations. The experimental data showed that the addition of barium sulphate to PMMA bone cement affected the fatigue strength of the material, whereas addition of gentamicin sulphate to the radiopaque PMMA had no effect on the fatigue properties of the bone cement. While PMMA with barium sulphate added was confirmed to have a reduced fatigue strength when compared with plain PMMA, no detrimental effect was found for the addition of gentamicin sulphate to radiopaque PMMA.
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Chang, Yuhan, Wen-Chien Chen, Pang-Hsin Hsieh, Dave W. Chen, Mel S. Lee, Hsin-Nung Shih, and Steve W. N. Ueng. "In VitroActivities of Daptomycin-, Vancomycin-, and Teicoplanin-Loaded Polymethylmethacrylate against Methicillin-Susceptible, Methicillin-Resistant, and Vancomycin-Intermediate Strains of Staphylococcus aureus." Antimicrobial Agents and Chemotherapy 55, no. 12 (September 19, 2011): 5480–84. http://dx.doi.org/10.1128/aac.05312-11.
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ABSTRACTThe objective of this study was to evaluate the antibacterial effects of polymethylmethacrylate (PMMA) bone cements loaded with daptomycin, vancomycin, and teicoplanin against methicillin-susceptibleStaphylococcus aureus(MSSA), methicillin-resistantStaphylococcus aureus(MRSA), and vancomycin-intermediateStaphylococcus aureus(VISA) strains. Standardized cement specimens made from 40 g PMMA loaded with 1 g (low-dose), 4 g (middle-dose) or 8 g (high-dose) antibiotics were tested for elution characteristics and antibacterial activities. The patterns of release of antibiotics from the cement specimens were evaluated usingin vitrobroth elution assay with high-performance liquid chromatography. The activities of broth elution fluid against differentStaphylococcus aureusstrains (MSSA, MRSA, and VISA) were then determined. The antibacterial activities of all the tested antibiotics were maintained after being mixed with PMMA. The cements loaded with higher dosages of antibiotics showed longer elution periods. Regardless of the antibiotic loading dose, the teicoplanin-loaded cements showed better elution efficacy and provided longer inhibitory periods against MSSA, MRSA, and VISA than cements loaded with the same dose of vancomycin or daptomycin. Regarding the choice of antibiotics for cement loading in the treatment ofStaphylococcus aureusinfection, teicoplanin was superior in terms of antibacterial effects.
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Heo, S. J., S. A. Park, H. J. Shin, Y. J. Lee, T. R. Yoon, H. Y. Seo, K. C. Ahn, S. E. Kim, and Jung Woog Shin. "Evaluation of Bonding Stress for the Newly Suggested Bone Cement: Comparison with Currently Used PMMA through Animal Studies." Key Engineering Materials 342-343 (July 2007): 373–76. http://dx.doi.org/10.4028/www.scientific.net/kem.342-343.373.
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PMMA remains the most popular material of bone cement for orthopaedic surgeries. However, conventional PMMA bone cement still has some problems. For this, we suggested new composite material (BBC) consisting of hydroxyapatite (45%), chitosan (10%) and PMMA. The purpose of this study was to evaluate the bonding stress at the interface of PMMA with additives and host bone using a rabbit model. After 6, 12 weeks of operation, the bonding stresses were evaluated by measuring shear stress through push-out test. The results of the tests showed that after 6 weeks the shear stress of the BBC was 2.65±0.29MPa and the PMMA was 1.21±0.31MPa (p<0.05). However, after 12 weeks, there were no significant differences between BBC and conventional PMMA bone cement. In SEM analysis, bone surface of BBC showed higher roughness than that of conventional PMMA bone cement after push-out test. From the study we conducted, addition of HA particles and chitosan to conventional PMMA bone cement showed promising results. The BBC has clinical potential of bone substitutes replacing conventional PMMA.
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Humphreys, P. K., J. F. Orr, and A. S. Bahrani. "An Investigation into the Effect of Cyclic Loading and Frequency on the Temperature of Pmma Bone Cement in Hip Prostheses." Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine 203, no. 3 (September 1989): 167–70. http://dx.doi.org/10.1243/pime_proc_1989_203_029_01.
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A titanium alloy hip prosthesis was inserted in a Tufnol tube representing the upper part of the femur. The prosthesis was cemented in the model femur using PMMA bone cement. Five thermocouples were embedded in the bone cement and the assembly was subjected to cyclic loading with a range of 0.3–4.5 kN at a frequency of 6 Hz. Temperature measurements over a 48 hour period indicated that the temperature rise in the bone cement was less than 4°C. It is concluded that such tests can be carried out at 6 Hz without significantly affecting the mechanical properties of PMMA bone cement.
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Cho, S. B., Sang Bae Kim, Keon Joon Cho, Ill Yong Kim, Chikara Ohtsuki, and Masanobu Kamitakahara. "In Vitro Aging Test for Bioactive PMMA-Based Bone Cement Using Simulated Body Fluid." Key Engineering Materials 284-286 (April 2005): 153–56. http://dx.doi.org/10.4028/www.scientific.net/kem.284-286.153.
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Novel PMMA-based bone cement using bioactive sol-gel derived CaO-SiO2 powder in order to induce bioactivity as well as to increase its mechanical property. The novel PMMA-based bone cements formed apatite on their surfaces in Simulated Body Fluid(SBF). In the present study, a change in mechanical property of the cement was evaluated using SBF. Before soaking in SBF, its compressive strength showed 80.6±2.1MPa. After soaking in SBF for 2 weeks, 8weeks and 9 weeks, its compressive strength were changed to 83.6±1.6MPa, 87.3±2.4MPa and 85.6±1.8MPa, respectively. It is clear that from the above result, there is no decrease in its compressive strength within 9 weeks soaking in SBF. That it hardly decreases in compressive strength of 7P3S bone cement in SBF is due to the relative small amount of gel powder or its spherical shape and monosize. Therefore, the newly developed PMMA-based cement can bond to the living bone and also be effectively used as bioactive bone cement without decrease in mechanical property.
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Ku, Kuan-Lin, Yu-Shan Wu, Chi-Yun Wang, Ding-Wei Hong, Zong-Xing Chen, Ching-An Huang, I.-Ming Chu, and Po-Liang Lai. "Incorporation of surface-modified hydroxyapatite into poly(methyl methacrylate) to improve biological activity and bone ingrowth." Royal Society Open Science 6, no. 5 (May 2019): 182060. http://dx.doi.org/10.1098/rsos.182060.
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Poly(methyl methacrylate) (PMMA) is the most frequently used bone void filler in orthopedic surgery. However, the interface between the PMMA-based cement and adjacent bone tissue is typically weak as PMMA bone cement is inherently bioinert and not ideal for bone ingrowth. The present study aims to improve the affinity between the polymer and ceramic interphases. By surface modifying nano-sized hydroxyapatite (nHAP) with ethylene glycol and poly(ɛ-caprolactone) (PCL) sequentially via a two-step ring opening reaction, affinity was improved between the polymer and ceramic interphases of PCL-grafted ethylene glycol-HAP (gHAP) in PMMA. Due to better affinity, the compressive strength of gHAP/PMMA was significantly enhanced compared with nHAP/PMMA. Furthermore, PMMA with 20 wt.% gHAP promoted pre-osteoblast cell proliferation in vitro and showed the best osteogenic activity between the composites tested in vivo . Taken together, gHAP/PMMA not only improves the interfacial adhesion between the nanoparticles and cement, but also increases the biological activity and affinity between the osteoblast cells and PMMA composite cement. These results show that gHAP and its use in polymer/bioceramic composite has great potential to improve the functionality of PMMA cement.
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Tan, Quan-chang, Jian-wei Wu, Fei Peng, Yuan Zang, Yang Li, Xiong Zhao, Wei Lei, and Zi-xiang Wu. "Augmented PMMA distribution: improvement of mechanical property and reduction of leakage rate of a fenestrated pedicle screw with diameter-tapered perforations." Journal of Neurosurgery: Spine 24, no. 6 (June 2016): 971–77. http://dx.doi.org/10.3171/2015.10.spine141275.
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OBJECTIVE This study investigated the optimum injection volume of polymethylmethacrylate (PMMA) to augment a novel fenestrated pedicle screw (FPS) with diameter-tapered perforations in the osteoporotic vertebral body, and how the distribution characteristics of PMMA affect the biomechanical performance of this screw. METHODS Two types of FPSs were designed (FPS-A, composed of 6 perforations with an equal diameter of 1.2 mm; and FPS-B, composed of 6 perforations each with a tapered diameter of 1.5 mm, 1.2 mm, and 0.9 mm from tip to head. Each of 28 human cadaveric osteoporotic vertebrae were randomly assigned to 1 of 7 groups: FPS-A1.0: FPS-A+1.0 ml PMMA; FPS-A1.5: FPS-A+1.5 ml PMMA; FPS-A2.0: FPS-A+2.0 ml PMMA; FPS-B1.0: FPS-B+1.0 ml PMMA; FPS-B1.5: FPS-B+1.5 ml PMMA; FPS-B2.0: FPS-B+2.0 ml PMMA; and conventional pedicle screws (CPSs) without PMMA. After the augmentation, 3D CT was performed to assess the cement distribution characteristics and the cement leakage rate. Axial pullout tests were performed to compare the maximum pullout force thereafter. RESULTS The CT construction images showed that PMMA bone cement formed a conical mass around FPS-A and a cylindrical mass around FPS-B. When the injection volume was increased from 1.0 ml to 2.0 ml, the distribution region of the PMMA cement was enlarged, the PMMA was distributed more posteriorly, and the risk of leakage was increased. When the injection volume reached 2.0 ml, the risk of cement leakage was lower for screws having diameter-tapered perforations. The pullout strengths of the augmented FPS-A groups and FPS-B groups were higher than that of the CPS group (p < 0.0001). All FPS-B groups had a higher pullout strength than the FPS-A groups. CONCLUSIONS The diameter of the perforations affects the distribution of PMMA cement. The diameter-tapered design enabled PMMA to form larger bone-PMMA interfaces and achieve a relatively higher pullout strength, although statistical significance was not reached. Study results indicated 1.5-ml of PMMA was a conservative volume for PMMA augmentation; more cement injection would significantly increase the risk of cement leakage.
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Paz, E., Y. Ballesteros, J. Abenojar, J. C. del Real, and N. J. Dunne. "Graphene Oxide and Graphene Reinforced PMMA Bone Cements: Evaluation of Thermal Properties and Biocompatibility." Materials 12, no. 19 (September 26, 2019): 3146. http://dx.doi.org/10.3390/ma12193146.
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The incorporation of well-dispersed graphene oxide (GO) and graphene (G) has been demonstrated as a promising solution to improve the mechanical performance of polymethyl methacrylate (PMMA) bone cements in an attempt to enhance the long-term survival of the cemented orthopaedic implants. However, to move forward with the clinical application of graphene-based PMMA bone cements, it is necessary to ensure the incorporation of graphene-based powders do not negatively affect other fundamental properties (e.g., thermal properties and biocompatibility), which may compromise the clinical success of the implant. In this study, the effect of incorporating GO and G on thermal properties, biocompatibility, and antimicrobial activity of PMMA bone cement was investigated. Differential scanning calorimetry studies demonstrated that the extent of the polymerisation reaction, heat generation, thermal conductivity, or glass transition temperature were not significantly (p > 0.05) affected by the addition of the GO or G powders. The cell viability showed no significant difference (p > 0.05) in viability when MC3-T3 cells were exposed to the surface of G- or GO-PMMA bone cements in comparison to the control. In conclusion, this study demonstrated the incorporation of GO or G powder did not significantly influence the thermal properties or biocompatibility of PMMA bone cements, potentially allowing its clinical progression.
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Luo, Kefeng, Guoqiang Jiang, Jinjin Zhu, Bin Lu, Jiye Lu, Kai Zhang, Xiumei Wang, and Fu-Zhai Cui. "Poly(methyl methacrylate) bone cement composited with mineralized collagen for osteoporotic vertebral compression fractures in extremely old patients." Regenerative Biomaterials 7, no. 1 (January 16, 2020): 29–34. http://dx.doi.org/10.1093/rb/rbz045.
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Abstract To examine the clinical effects of a new bone cement composed of poly(methyl methacrylate) (PMMA) and mineralized collagen (MC) compared with pure PMMA bone cement in treating osteoporotic vertebral compression fractures (OVCFs) in patients aged over 80. In all, 32 cases using pure PMMA bone cement and 31 cases using MC-modified PMMA (MC-PMMA) bone cement for OVCFs between June 2014 and March 2016 were screened as PMMA group and MC-PMMA group, respectively, with an average age of over 80. The operation duration, intraoperative blood loss, hospital stay, oswestry disability index (ODI), visual analogue scale (VAS), anterior vertebral height (AVH), intermediate vertebral height (IVH) and posterior vertebral height (PVH) of injured vertebrae, vertebral computed tomography value, re-fracture rate of adjacent vertebrae, correction rate of spinal kyphotic angle and wedge-shaped vertebra angle and surgical complications were compared between the two groups. In the early post-operative period, the VAS, ODI, AVH and IVH in MC-PMMA group were comparable to those in the traditional PMMA group. Moreover, the MC-PMMA group showed better effects compared with the PMMA group 12 months after surgery. Thus, this new bone cement has superior clinic effects in the long term.
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Aghyarian, Shant, Lucas C. Rodriguez, Jonathan Chari, Elizabeth Bentley, Victor Kosmopoulos, Isador H. Lieberman, and Danieli C. Rodrigues. "Characterization of a new composite PMMA-HA/Brushite bone cement for spinal augmentation." Journal of Biomaterials Applications 29, no. 5 (August 1, 2014): 688–98. http://dx.doi.org/10.1177/0885328214544770.
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Calcium phosphate fillers have been shown to increase cement osteoconductivity, but have caused drawbacks in cement properties. Hydroxyapatite and Brushite were introduced in an acrylic two-solution cement at varying concentrations. Novel composite bone cements were developed and characterized using rheology, injectability, and mechanical tests. It was hypothesized that the ample swelling time allowed by the premixed two-solution cement would enable thorough dispersion of the additives in the solutions, resulting in no detrimental effects after polymerization. The addition of Hydroxyapatite and Brushite both caused an increase in cement viscosity; however, these cements exhibited high shear-thinning, which facilitated injection. In gel point studies, the composite cements showed no detectable change in gel point time compared to an all-acrylic control cement. Hydroxyapatite and Brushite composite cements were observed to have high mechanical strengths even at high loads of calcium phosphate fillers. These cements showed an average compressive strength of 85 MPa and flexural strength of 65 MPa. A calcium phosphate-containing cement exhibiting a combination of high viscosity, pseudoplasticity and high mechanical strength can provide the essential bioactivity factor for osseointegration without sacrificing load-bearing capability.
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Ayre, Wayne Nishio, Nicole Scully, Carole Elford, Bronwen AJ Evans, Wendy Rowe, Jeff Rowlands, Ravi Mitha, et al. "Alternative radiopacifiers for polymethyl methacrylate bone cements: Silane-treated anatase titanium dioxide and yttria-stabilised zirconium dioxide." Journal of Biomaterials Applications 35, no. 10 (February 11, 2021): 1235–52. http://dx.doi.org/10.1177/0885328220983797.
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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.
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Rochat, M. C., K. E. Bartels, M. E. Payton, R. J. Hoffman, St A. Schafer, D. Dickey, and D. N. Lange. "Comparison of Carbon Dioxide Laser Modalities for Removal of Polymethylmethacrylate Cement." Veterinary and Comparative Orthopaedics and Traumatology 10, no. 01 (January 1997): 27–32. http://dx.doi.org/10.1055/s-0038-1632565.
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SummaryPolymethylmethacrylate (PMMA) cement is routinely used in a number of surgical procedures performed on human beings and animals. As the use of PMMA increases in veterinary medicine, the need for its removal during “revision” surgeries also increases. Common indications for removal of PMMA are infection, aseptic loosening, and fracture of the cement. Polymethylmethacrylate cement is often applied in areas of the body where typical mechanical methods of removal are dangerous or impossible. Cement placed near the spinal canal for the treatment of caudal cervical malformation-malarticulation syndrome or deep within the femoral medullary canal for total hip prostheses are examples. The ability to safely and easily remove cement should lower intraoperative complication rates associated with revision surgeries.The vaporization efficiency for removal of PMMA cement for three carbon dioxide laser modalities (continuous wave only, with Swift-Lase™ attachment, and with Fiberlase™ wave guide) were determined, as well as heat transferred to periosteal surface during PMMA cement vaporization, and gross pathology to the cortical bone at the maximum vaporization efficiency power. Cefazolin sodium was added to half of the samples to determine if the ablation ablation rate of PMMA would be affected. The C02 laser with wave guide was the most efficient modality for vaporization at 25 watts, and produced significantly less heat transfer to the periosteal surface than the heat of polymerization of the PMMA cement. Cefazolin sodium appeared to slightly decrease the vaporization efficiency, and all of the lasers produced gross and histologic lesions to the bone.Three laser types were compared for their ability to efficiently and safely remove polymethylmethacrylate (PMMA) cement. Vaporization rates were determined. The most efficient wattage for each laser modality was used to compare the heat transferred during PMMA removal as well as the pathology created by application of each laser modality to the cortical bone. The CO2 laser with wave guide at 25 watts was the most efficient modality for vaporization of PMMA cement, and produced significantly less heat transfer to the periosteal surface than the CO2 laser and the CO2 laser with Swift-Lase™.
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Robo, Céline, David Wenner, S. J. Kumari A. Ubhayasekera, Jöns Hilborn, Caroline Öhman-Mägi, and Cecilia Persson. "Functional Properties of Low-Modulus PMMA Bone Cements Containing Linoleic Acid." Journal of Functional Biomaterials 12, no. 1 (January 17, 2021): 5. http://dx.doi.org/10.3390/jfb12010005.
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Acrylic bone cements modified with linoleic acid are a promising low-modulus alternative to traditional high-modulus bone cements. However, several key properties remain unexplored, including the effect of autoclave sterilization and the potential use of low-modulus cements in other applications than vertebral augmentation. In this work, we evaluate the effect of sterilization on the structure and stability of linoleic acid, as well as in the handling properties, glass transition temperature, mechanical properties, and screw augmentation potential of low-modulus cement containing the fatty acid. Neither 1H NMR nor SFC-MS/MS analysis showed any detectable differences in autoclaved linoleic acid compared to fresh one. The peak polymerization temperature of the low-modulus cement was much lower (28–30 °C) than that of the high-modulus cement (67 °C), whereas the setting time remained comparable (20–25 min). The Tg of the low-modulus cement was lower (75–78 °C) than that of the high-stiffness cement (103 °C). It was shown that sterilization of linoleic acid by autoclaving did not significantly affect the functional properties of low-modulus PMMA bone cement, making the component suitable for sterile production. Ultimately, the low-modulus cement exhibited handling and mechanical properties that more closely match those of osteoporotic vertebral bone with a screw holding capacity of under 2000 N, making it a promising alternative for use in combination with orthopedic hardware in applications where high-stiffness augmentation materials can result in undesired effects.
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Khan, Aqsa, Ghazna Hassan Khan, Eraj Humayun Mirza, Alidad Chandio, Maliha Mohsin, Mahnoor Hassan, Manal Naushad, and Ali Raza Jafri. "Development and Characterization of Acrylic Based Bone Cements." Journal of Biomaterials and Tissue Engineering 12, no. 3 (March 1, 2022): 471–79. http://dx.doi.org/10.1166/jbt.2022.2933.
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Bone tissue engineering has emerged as a multidisciplinary field in recent times with an aim to expedite the process of regeneration of damaged or diseased tissues. This study is an attempt to fabricate and characterize Tricalcium Phosphate (TCP) and Chitosan incorporated Polymethylmethacrylate (PMMA) based bone cement. In total two experimental PMMA based bone cements were fabricated that were differentiated by presence and absence of Chitosan. In both groups (10 and 30 wt.%) TCP were incorporated into Methyl methacrylate (MMA) monomer. PMMA was used as a control. The physical, mechanical and thermal properties of the composites were assessed. Morphological changes of PMMA after the introduction of TCP and Chitosan were observed by means of X-ray diffraction (XRD). Major peak shifts in Fourier transform Infrared spectroscopy (FTIR) spectra demonstrated the strong bonding of PMMA with incorporated materials. PMMA incorporated with 10% TCP showed the maximum wettability in absence of Chitosan. Hardness of the tested specimens decreased with increasing content of TCP which in turns enhanced ductility. It was also observed that neither of the samples showed significant degradation. The incorporation of additives enhance the physical and chemical properties of PMMA as bone cement.
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Wang, Haiyang, Toshinari Maeda, and Toshiki Miyazaki. "Effect of Calcium Acetate Content on Apatite-Forming Ability and Mechanical Property of PMMA Bone Cement Modified with Quaternary Ammonium." Materials 13, no. 21 (November 6, 2020): 4998. http://dx.doi.org/10.3390/ma13214998.
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Polymethyl methacrylate (PMMA)-based bone cement is a popular biomaterial used for fixation of artificial joints. A next-generation bone cement having bone-bonding ability, i.e., bioactivity and antibacterial property is desired. We previously revealed that PMMA cement added with 2-(tert-butylamino)ethyl methacrylate, γ-methacryloxypropyltrimethoxysilane and calcium acetate showed in vitro bioactivity and antibacterial activity. This cement contains calcium acetate at 20% of the powder component. Lower content of the calcium acetate is preferable, because the release of a lot of calcium salt may degrade mechanical properties in the body environment. In the present study, we investigate the effects of calcium acetate content on the setting property and mechanical strength of the cement and apatite formation in simulated body fluid (SBF). The setting time increased and the compressive strength decreased with an increase in calcium acetate content. Although the compressive strength decreased after immersion in SBF for 7 d, all the cements still satisfied the requirements of ISO5833. Apatite was formed in SBF within 7 d on the samples where the calcium acetate content was 5% or more. Therefore, it was found that PMMA cement having antibacterial properties and bioactivity can be obtained even if the amount of the calcium acetate is reduced to 5%.
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Zheng, Xiaoqiang, Yifan Wang, Jingyu Liu, Jintong Han, Zhenduo Cui, Shuilin Wu, Yanqin Liang, Shengli Zhu, Xiang Ge, and Zhaoyang Li. "Gelatin/gentamicin sulfate-modified PMMA bone cement with proper mechanical properties and high antibacterial ability." Materials Research Express 9, no. 3 (March 1, 2022): 035405. http://dx.doi.org/10.1088/2053-1591/ac5e1f.
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Abstract With the aging of the population, the risk of osteoporotic vertebral compression fractures (OVCF) caused by osteoporosis increases rapidly. Surgeons often fill the bone defect with injectable polymethylmethacrylate (PMMA) bone cement through vertebroplasty. However, compared with cancellous bone, the higher mechanical properties of PMMA bone cement can easily lead to the fracture of the adjacent cone. Besides, the wound infection caused by surgery is also a serious problem. In order to solve these problems, we designed a new type of PMMA bone cement, by adding gelatin as a pore former, 5% (w/w) gentamicin sulfate (GS) for antibacterial purpose, and 30% (w/w) barium sulfate (BaSO4) to provide excellent radiopacity. Compared with the traditional PMMA bone cement, with the dissolution of gelatin after being immersed in phosphate buffered saline (PBS) for 14 d, the mechanical properties of modified PMMA bone cement decreased by approximately 67%, which is close to the human cancellous bone. Besides, the release of GS increased 3.8 times, and the GS concentration remained above the minimum inhibitory concentration (MIC) for 12 d. In addition, the setting properties, contact angle, antibacterial ability, and cell compatibility of PMMA bone cement also maintained well. The integration and dissolution of gelatin were observed by a scanning electron microscope (SEM). All results indicate that the new type of gelatin-modified PMMA bone cement is a potential candidate material for vertebroplasty.
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Tai, Ching-Lung, Po-Liang Lai, Wei-De Lin, Tsung-Tin Tsai, Yen-Chen Lee, Mu-Yi Liu, and Lih-Huei Chen. "Modification of Mechanical Properties, Polymerization Temperature, and Handling Time of Polymethylmethacrylate Cement for Enhancing Applicability in Vertebroplasty." BioMed Research International 2016 (2016): 1–8. http://dx.doi.org/10.1155/2016/7901562.
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Polymethylmethacrylate (PMMA) bone cement is a popular bone void filler for vertebroplasty. However, the use of PMMA has some drawbacks, including the material’s excessive stiffness, exothermic polymerization, and short handling time. This study aimed to create an ideal modified bone cement to solve the above-mentioned problems. Modified bone cements were prepared by combining PMMA with three different volume fractions of castor oil (5%, 10%, and 15%). The peak polymerization temperatures, times to achieve the peak polymerization temperature, porosities, densities, modulus and maximum compression strengths of standard (without castor oil), and modified cements were investigated following storage at ambient temperature (22°C) or under precooling conditions (3°C). Six specimens were tested in each group of the aforementioned parameters. Increasing castor oil content and precooling treatment effectively decreased the peak polymerization temperatures and increased the duration to achieve the peak polymerization temperature (P<0.05). Furthermore, the mechanical properties of the material, including density, modulus, and maximum compression strength, decreased with increasing castor oil content. However, preparation temperature (room temperature versus precooling) had no significant effect (P>0.05) on these mechanical properties. In conclusion, the addition of castor oil to PMMA followed by precooling created an ideal modified bone cement with a low modulus, low polymerization temperature, and long handling time, enhancing its applicability and safety for vertebroplasty.
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Cojocaru, Ileana, Doina Prodan, Violeta Popescu, and Marioara Moldo. "SEM Analysis of Composites with TCP/HA/Chitosan/Poly (Methylmethacrilate)." Materiale Plastice 54, no. 1 (March 30, 2017): 60–62. http://dx.doi.org/10.37358/mp.17.1.4786.
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Modified cement composites were prepared by dispersing commercially available PMMA powders and chitosan/ tricalcium phosphate (TCP) or chitosan / hydroxyapatite (HA) fillers into a PMMA matrix. SEM and EDX were used to determine the compounds and the morphology of the composite. The characteristics of these materials indicate that the addition of chitosan/TCP and chitosan /HA as a constituent into the PMMA cement significantly decreases the curing peak temperature. Furthermore, the setting time increases from 4 min to 7 min, as compared to the PMMA cement. These changes could be beneficial for the handling of the bone cement paste and causing less damage to the surrounding tissues.
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Zaza, Amin, Mohamed Habib, and Nabil Fatahalla. "Properties of PMMA Bone Cement Modified with Nano-hydroxyapatite and Acetone." Academic Research Community publication 2, no. 4 (January 1, 2019): 489. http://dx.doi.org/10.21625/archive.v2i4.393.
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Fracture in the adjacent levels is one of the consequences to the use of commercial
poly methylmethacrylate (PMMA) bone cement. Modified PMMA with a reduced Young’s modulus was found to be safer for cancellous bone augmentation procedures. The aim of this research was to study the effect of adding hydroxyapatite (HA) nano-particles and acetone on different properties of PMMA cement. A commercial PMMA cement was used as a model for bone cement. Three groups of modified PMMA/nano-HA were investigated by adding 2, 4 and 6 wt. % of HA. Acetone as a porogen mixed with distilled water in different amounts (A/W: 1:1, 2:1.5 and 2:1g) was used to produce porous PMMA cement. The residual monomer, polymerization and mechanical properties under tension and compression tests were investigated. Young’s modulus detected from compression test decreased from 826.5±10 to 728±66 MPa by adding 6wt.% HA. Adding acetone to PMMA with 2:1.5g (A/W) has decreased the compressive Young’s modulus to 753±38 MPa. High Performance Liquid Chromatography (HPLC)
measurements were carried out with intervals of 2 hours, 6 hours and 24 hours to evaluate the residual monomer for all groups. The amount of residual monomer has decreased after 24 hours of curing by adding acetone and nano-HA. Modifying PMMA by HA and acetone have inconsistent effect on the polymerization temperature. It was concluded that HA and acetone can be used to reduce the stiffness and residual monomer with enhanced biocompatibility of the commercial PMMA bone cement.
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Valle, A. González Della, F. Piccaluga, V. Alfie, and E. A. Salvati. "Polymethylmethacrylate Venogram after Cemented Arthroplasty of the Hip. A Report of Seven Cases and Review of the Literature." HIP International 13, no. 3 (July 2003): 184–88. http://dx.doi.org/10.1177/112070000301300310.
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We present seven patients with polymethylmethacrylate (PMMA) filling the veins accompanying the second perforating branch of the profunda femoris artery detected after primary cemented hip arthroplasty. All implants were cemented utilizing retrograde canal filling with a cement pistol and pressurization. No haemodynamic changes were observed throughout any of the procedures and all patients had an uneventful recovery and evolution. The presence of a PMMA venogram is an infrequent finding after cemented hip arthroplasty. In our seven cases it was not associated with higher peri-operative morbidity. Differential diagnoses must be made with cement extruded through incomplete fractures or through femoral screw holes, as treatment and weightbearing status may differ.
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Boulouis, H. J., P. Moissonnier, and M. Cariou. "Inclusion of marbofloxacin in PMMA orthopaedic cement." Veterinary and Comparative Orthopaedics and Traumatology 19, no. 02 (2006): 106–9. http://dx.doi.org/10.1055/s-0038-1632983.
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SummaryThis in vitro experimental study investigated the feasibility for marbofloxacin, a veterinary fluoroquinolone antibiotic, to retain its antibacterial activity after its inclusion in polymethylmethacrylate (PMMA) cement. The assays were conducted on gelose cultures of various types of bacteria isolated from canine spontaneous osteomyelitis. The efficiency of the antibiotics was assessed by using an antibiogram method. Resistance of marbofloxacin to the temperature observed during PMMA polymerization, antimicrobial effect of galenic, useful concentrations and comparison with gentamicin (reference antibiotic for this use) were evaluated. Marbofloxacin retained its antimicrobial activity after being heated to high temperatures reached during polymerization. The more effective galenic form to incorporate into the PMMA monomer was the marbofloxacin powder and the appropriate concentration was 1/40°. In this experiment, marbofloxacin included in PMMA showed a good antimicrobial activity; however this activity was lower than gentamicin added to PMMA on Gram + and Pseudomonas bacteria.Therefore, it seems useful to incorporate marbofloxacin to PMMA cement to treat, or to prevent, osteomyelitis associated with marbofloxacin sensitive bacteria.Nevertheless, the development of a marbofloxacin-PMMA cement requires further evaluation, especially pharmacological, biomechanical and clinical.
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Oosterom, R., R. A. J. van Ostayen, V. Antonelli, and H. E. N. Bersee. "Effect of Interface Conditions between Ultrahigh Molecular Weight Polyethylene and Polymethyl Methacrylate Bone Cement on the Mechanical Behaviour of Total Shoulder Arthroplasty." Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine 219, no. 6 (June 1, 2005): 425–35. http://dx.doi.org/10.1243/095441105x34455.
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The aim of this study was to investigate the effect of the interface condition between polymethyl methacrylate (PMMA) bone cement and the ultrahigh molecular weight (UHMWPE) glenoid component on cement stresses and glenoid component tilting in a finite element (FE) model. The background of this research is that most FE models assume bonding between the PMMA bone cement and the UHMWPE component, although it is very doubtful that this bonding is present. An FE model of a cemented glenoid component was developed and a joint compression force and subluxation force of 725 and 350 N respectively were applied. The maximal principal stresses in the cement layer ranged between 21.30 and 32.18 MPa. Glenoid component tilting ranged between 0.943° and 0.513°. It was found that the interface condition has a large effect on the maximal principal stresses and glenoid component tilting. Whether adhesion between the UHMWPE component and PMMA bone cement occurs is unknown beforehand and, as a result, design validation using the FE technique should be carried out both by using contact elements in combination with a coefficient of friction as well as by a full bonding at this interface.
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Moliterno, Jennifer A., Lynn L. Mubita, Clark Huang, and John A. Boockvar. "High-viscosity polymethylmethacrylate cement for endoscopic anterior cranial base reconstruction." Journal of Neurosurgery 113, no. 5 (November 2010): 1100–1105. http://dx.doi.org/10.3171/2010.3.jns09453.
Full textAbstract:
Endoscopic endonasal transsphenoidal surgery (ETSS) is an effective, minimally invasive approach for the resection of anterior skull base tumors. Cerebrospinal leakage is a common complication, and repair of the anterior skull base defect with alloplastic materials has been used to minimize the risk of postoperative CSF rhinorrhea and meningitis. Injectable cements, such as low-viscosity polymethylmethacrylate (PMMA), are useful for cranial base reconstruction because they are easy to shape to the contour of the defect. These low-viscosity materials, however, are more susceptible to leakage into the nasal cavity prohibiting their use and are prone to cracking upon hardening. Cement extravasation not only obstructs the operator's view during placement, but it is also associated with significant local and systemic complications. High-viscosity (HV) PMMA–based cement and its specialized delivery system have recently been shown to be safe and effective in human applications. Moreover, its constant high viscosity significantly reduces cement leakage and its associated complications. The authors hypothesized that this type of cement would therefore be ideal for ETSS to repair anterior skull base defects. The authors report their experience using HV-PMMA to reconstruct the anterior skull base in 12 patients following ETSS. The unique puttylike consistency of this material is easy to work, malleable, does not leak into the nasal cavity, does not aspirate into suction tubing, and hardens without cracks in less than 10 minutes. None of the 12 patients suffered postoperative CSF leaks or infections more than 8 months, on average, after surgery. Although not necessary in all cases of ETSS, the authors conclude that HV-PMMA, if needed, may be an excellent choice for reconstructing the anterior skull base after ETSS. Further studies are needed to better assess the long-term outcomes of HV-PMMA cement and its use in repairing skull base defects after extended ETSS.
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Schauwecker, Johannes, Mark Bock, Florian Pohlig, Heinz Mühlhofer, Jutta Tübel, Rüdiger von Eisenhart-Rothe, and Chlodwig Kirchhoff. "In vitro Growth Pattern of Primary Human Osteoblasts on Calcium Phosphate- and Polymethylmethacrylate-Based Bone Cement." European Surgical Research 58, no. 5-6 (2017): 216–26. http://dx.doi.org/10.1159/000470839.
Full textAbstract:
Background/Purpose: Polymethylmethacrylate (PMMA) and calcium phosphate (Ca-P) cements are widely used for arthroplasty surgery and augmentation of bone defects. However, aseptic implant loosening in absence of wear-induced osteolysis indicates an unfavourable interaction between the cement surface and human osteoblasts. Our underlying hypothesis is that cement surfaces directly modify cell viability, proliferation rate, and cell differentiation. Methods: To test this hypothesis, we examined primary human osteoblasts harvested from six individuals. These cells were pooled and subsequently seeded directly on cement pellets prepared from Palacos® R, Palacos® R+G, and Norian® Drillable cements. After incubation for 24 and 72 h, cell viability, proliferation rate, apoptosis rate, and cell differentiation were analysed. Results: Upon cultivation of human osteoblasts on cement surfaces, we observed a significantly reduced cell viability and DNA content compared to the control. Analysis of the apoptosis rate revealed an increase for cells on Palacos R and Norian Drillable, but a significant decrease on Palacos R+G compared to the control. Regarding osteogenic differentiation, significantly lower values of alkaline phosphatase enzyme activity were identified for all cement surfaces after 24 and 72 h compared to cultivation on tissue culture plastic, serving as control. Conclusions: In summary, these data suggest a limited biocompatibility of both PMMA and Ca-P cements, necessitating further research to reduce unfavourable cell-cement interactions and consequently extend implant survival.
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Chung, Ren Jei, Keng Liang Ou, and Han Wen Liang. "Polymethylmethacrylate Composite Bone Cement Adding with Tetracalcium Phosphate." Key Engineering Materials 696 (May 2016): 89–92. http://dx.doi.org/10.4028/www.scientific.net/kem.696.89.
Full textAbstract:
Polymethylmethacrylate (PMMA) cement has been used in orthopedics for more than 70 years. The advantages of PMMA bone cement include high compressive strength, stickiness, deformable ability and rapid self-setting. But the heat produced during polymerization would hinder the recovery. In order to improve the properties, in this research we added tetracalcium phosphate (TTCP) into polymethylmethacrylate cement as TP cement. A serious of characterizations including thermal property study, compression strength and micor-CT evaluation were carried out. According to the results, the polymerization heat was significantly reduced for the TP cement. The compressive strength was also enhanced with TTCP addition. TP-10 had better properties. As to thermal tests, TP-40 showed better results. Micro CT was used to monitor the composition inside the materials, and the results showed that TTCP was well dispersed in the PMMA matrix. The composite PMMA bone cement adding with tetracalcium phosphate seemed to be a potential candidate as low temperature product.
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Xia, Xue, Rui Shi, Jinhui Huang, Yubao Li, Yi Zuo, and Jidong Li. "Development of a phase change microcapsule to reduce the setting temperature of PMMA bone cement." Journal of Applied Biomaterials & Functional Materials 18 (January 2020): 228080002094027. http://dx.doi.org/10.1177/2280800020940279.
Full textAbstract:
The aim of the current study is to alleviate the adverse effect of the strongly exothermic polymerization of polymethyl methacrylate (PMMA) bone cement in clinical applications. In this study, paraffin/poly(methyl methacrylate–methylene bisacrylamide) (paraffin/P(MMA-MBA)) phase change microcapsules (MPn; n = 1, 2) were developed via the emulsion polymerization method. The reduction of the maximum temperature of polymerization (Tmax) and physicochemical properties were evaluated after doping commercial PMMA cement with MPn in specific proportions (10%, 20%, and 30%). The results reveal that the MPn-doped PMMA exhibited an effective reduction in Tmax, which can help alleviate the adverse effect of the strong exothermic reactions during PMMA setting. After doping with the MPn, the mechanical properties of the PMMA cement decrease and the values are close to that of body cancellous bone. The Tmax of the cement doped with 20 wt% MP1 is 37.6°C, which is close to body temperature. Significantly, the setting and compressive properties of the optimized group can still adhere to clinical requirements. The MPn doping PMMA technique holds much promise in clinical practice.
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Vyrva, Oleg, Olexii Goncharuk, and Natalia Lysenko. "Comparative evaluation of polymethylmethacrylate and composite bone cements. Review of the experimental studies results." ORTHOPAEDICS, TRAUMATOLOGY and PROSTHETICS, no. 1 (October 5, 2021): 86–91. http://dx.doi.org/10.15674/0030-59872021186-91.
Full textAbstract:
Current article is a review of experimental studies of different bone cements types and their combinations. Providing of bone fragments stable fixation at osteosynthesis in cases of difficult multifragmental fractures, arthroplasties and other implants using especially in the osteoporosis conditions is a main task of orthopaedic surgery procedures. Polymethylmethacrylate (PMMA) is the first material that is answered to these requirements. The evolution of bone cements resulted in creation of a new composite substance — combination of PMMA and β-threecalciumphosfates (β-TCPh). Combination of these two components allowed to provide high bioabsorbal, osteoconductive and osteointegrative properties along with sufficient durability. In the analyzed works the properties of composite cement CalCemex were evaluated in vivo experiment. It was found that in the case of PMMA penetration of bone tissue into the polymer structure did not occur. Under the conditions of using bone cement with β-TCF admixture, the formation of bone tissue was observed not only on the surface of the implant, but also in the external and internal pores. It is the presence of pores in CalCemex that the authors explain the possibility of penetration of cellular elements, blood vessels and bone formation. Moreover, β-TCPh is included into this material and it is bioresorbed by osteoclasts. This leads to the release of calcium and phosphorus ions and, consequently, simplifies the attachment of the newly formed bone to the bone cement. We assume that composite cement like CalCemex type is a promising material for the treatment of various types of fractures and replacement of bone defects. It should be mentioned that research in this area is ongoing and intensive work is underway to synthesize and study the results of clinical application of composite bone cements with maximum bioactive properties that will not only strengthen bone tissue but also perform osteointegrative function. Key words. Bone cement, polymethylmethacrylate, β-threecalciumphosfates, experiment.
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Tan, Hong-lue, Hai-yong Ao, Rui Ma, Wen-tao Lin, and Ting-ting Tang. "In VivoEffect of Quaternized Chitosan-Loaded Polymethylmethacrylate Bone Cement on Methicillin-Resistant Staphylococcus epidermidis Infection of the Tibial Metaphysis in a Rabbit Model." Antimicrobial Agents and Chemotherapy 58, no. 10 (July 28, 2014): 6016–23. http://dx.doi.org/10.1128/aac.03489-14.
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ABSTRACTInfection of open tibial fractures with contamination remains a challenge for orthopedic surgeons. Local use of antibiotic-impregnated polymethylmethacrylate (PMMA) beads and blocks is a widely used procedure to reduce the risk of infection. However, the development of antibiotic-resistant organisms make the management of infection more difficult. Ourin vitrostudy demonstrated that quaternized chitosan (hydroxypropyltrimethyl ammonium chloride chitosan [HACC])-loaded PMMA bone cement exhibits strong antibacterial activity toward antibiotic-resistant bacteria. Therefore, the present study aimed to investigate thein vivoantibacterial activity of quaternized chitosan-loaded PMMA. Twenty-four adult female New Zealand White rabbits were used in this study. The right proximal tibial metaphyseal cavity was prepared, 107CFU of methicillin-resistantStaphylococcus epidermidiswas inoculated, and PMMA-only, gentamicin-loaded PMMA (PMMA-G), chitosan-loaded PMMA (PMMA-C), or HACC-loaded PMMA (PMMA-H) bone cement cylinders were inserted. During the follow-up period, the infections were evaluated using X rays on days 21 and 42 and histopathological and microbiological analyses on day 42 after surgery. Radiographic indications of bone infections, including bone lysis, periosteal reactions, cyst formation, and sequestral bone formation, were evident in the PMMA, PMMA-G, and PMMA-C groups but not in the PMMA-H group. The radiographic scores and gross bone pathological and histopathological scores were significantly lower in the PMMA-H group than in the PMMA, PMMA-G, and PMMA-C groups (P< 0.05). Explant cultures also indicated significantly less bacterial growth in the PMMA-H group than in the PMMA, PMMA-G, and PMMA-C groups (P< 0.01). We concluded that PMMA-H bone cement can inhibit the development of bone infections in this animal model inoculated with antibiotic-resistant bacteria, thereby demonstrating its potential application for treatment of local infections in open fractures.
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Al Thaher, Yazan, Raida Khalil, Sharif Abdelghany, and Mutaz S. Salem. "Antimicrobial PMMA Bone Cement Containing Long Releasing Multi-Walled Carbon Nanotubes." Nanomaterials 12, no. 8 (April 18, 2022): 1381. http://dx.doi.org/10.3390/nano12081381.
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Prosthetic joint infections (PJIs) ensued from total joint replacement (TJR) pose a severe threat to patients that involve poor health outcomes, severe pain, death (in severe cases), and negative influence patients’ quality of life. Antibiotic-loaded bone cement (ALBC) is frequently used for the prevention and treatment of PJI. This work aims to study gentamicin release from carbon nanotubes (CNTs) incorporated in polymethyl methacrylate (PMMA) bone cement to prolong release over several weeks to provide prophylaxis from PJIs after surgery. Different CNT concentrations were tested with the presence of gentamicin as a powder or preloaded onto carboxyl functionalized CNTs. The different types of bone cement were tested for drug release, mechanical properties, water uptake, antimicrobial properties, and cytocompatibility with human osteoblast cells (MTT, LDH, alizarin red, and morphology). Results showed prolonged release of gentamicin from CNT-loaded bone cements over several weeks compared to gentamicin-containing bone cement. Additionally, the presence of CNT enhanced the percentage of gentamicin released without adversely affecting the nanocomposite mechanical and antimicrobial properties needed for performance. Cytotoxicity testing showed non-inferior performance of the CNT-containing bone cement to the equivalent powder containing cement. Therefore, the developed nanocomposites may serve as a novel PMMA bone cement to prevent PJIs.
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Orr, J. F., and N. J. Dunne. "Measurement of Shrinkage Stresses in PMMA Bone Cement." Applied Mechanics and Materials 1-2 (September 2004): 127–32. http://dx.doi.org/10.4028/www.scientific.net/amm.1-2.127.
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Polymethyl methacrylate (PMMA) bone cement comprises liquid methyl methacrylate monomer and PMMA beads, the former encapsulating the beads and polymerising within 10 minutes of mixing. Up to 7% volumetric shrinkage accompanies the exothermic polymerisation reaction and subsequent cooling induces residual thermal stresses when the cement is restrained around implant components. The authors have measured shrinkages, calculated residual stresses by closed form solutions and measured stresses by a range of methods. Full field optical displacement measurement has been used to derive strains and stresses in rings of cement cooling by 50oC under representative restraints and the hole drilling technique has been applied to cured PMMA cement. A strain gauged transducer developed to measure shrinkage forces in cement rings for derivation of contact stresses. The theoretical results predict stresses in the range 10-25MPa for a range of curing temperatures. These results are supported by the experimental methods and also by subsequent finite element models. The acquisition of these results required experimental characterisation of proprietary PMMA cements, particularly in terms of elastic modulus (up to 2.65GPa) and Poisson’s Ratio (0.455). It is concluded that the thermally induced stresses are sufficient to cause cracking around hip replacement femoral stems at the stem/cement interface, in the immediate post-curing phase and prior to functional loading of the implant. Cracks of this type have been reported from clinical studies and the authors have reproduced such cracks in laboratory models of hip replacements. It is proposed that the cracks are likely to propagate by the mechanism of fatigue under cyclic loading. It is concluded that thermal stresses are important in failure of hip replacements by aseptic loosening, the most common reported indicator for implant revision. There are few references in literature that address this issue directly, however the results of this work are supportive of the measurements and observations reported and provide an explanation and understanding of the initiation of failures.
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Wang, Haiyang, Toshinari Maeda, and Toshiki Miyazaki. "Preparation of bioactive and antibacterial PMMA-based bone cement by modification with quaternary ammonium and alkoxysilane." Journal of Biomaterials Applications 36, no. 2 (March 24, 2021): 311–20. http://dx.doi.org/10.1177/08853282211004413.
Full textAbstract:
Bone cement based on poly(methyl methacrylate) (PMMA) powder and methyl methacrylate (MMA) liquid is a very popular biomaterial used for the fixation of artificial joints. However, there is a risk of this cement loosening from bone because of a lack of bone-bonding bioactivity. Apatite formation in the body environment is a prerequisite for cement bioactivity. Additionally, suppression of infection during implantation is required for bone cements to be successfully introduced into the human body. In this study, we modified PMMA cement with γ-methacryloxypropyltrimetoxysilane and calcium acetate to introduce bioactive properties and 2-( tert-butylamino)ethyl methacrylate (TBAEMA) to provide antibacterial properties. The long-term antibacterial activity is attributed to the copolymerization of TBAEMA and MMA. As the TBAEMA content increased, the setting time increased and the compressive strength decreased. After soaking in simulated body fluid, an apatite layer was detected within 7 days, irrespective of the TBAEMA content. The cement showed better antibacterial activity against Gram-negative E. Coli than Gram-positive bacteria; however, of the Gram-positive bacteria investigated, B. subtilis was more susceptible than S. aureus.