Potential Operating Room Fire Hazard of Bone Cement.

PubMed

Sibia, Udai S; Connors, Kevin; Dyckman, Sarah; Zahiri, Hamid R; George, Ivan; Park, Adrian E; MacDonald, James H

Approximately 600 cases of operating room (OR) fires are reported annually. Despite extensive fire safety education and training, complete elimination of OR fires still has not been achieved. Each fire requires an ignition source, a fuel source, and an oxidizer. In this case report, we describe the potential fire hazard of bone cement in the OR. A total knee arthroplasty was performed with a standard medial parapatellar arthrotomy. Tourniquet control was used. After bone cement was applied to the prepared tibial surface, the surgeon used an electrocautery device to resect residual lateral meniscus tissue-and started a fire in the operative field. The surgeon suffocated the fire with a dry towel and prevented injury to the patient. We performed a PubMed search with a cross-reference search for relevant papers and found no case reports outlining bone cement as a potential fire hazard in the OR. To our knowledge, this is the first case report identifying bone cement as a fire hazard. OR fires related to bone cement can be eliminated by correctly assessing the setting time of the cement and avoiding application sites during electrocautery.

Fiber-enriched double-setting calcium phosphate bone cement.

PubMed

dos Santos, Luís Alberto; Carrodéguas, Raúl Garcia; Boschi, Anselmo Ortega; Fonseca de Arruda, Antônio Celso

2003-05-01

Calcium phosphate bone cements are useful in orthopedics and traumatology, their main advantages being their biocompatibility and bioactivity, which render bone tissue osteoconductive, providing in situ hardening and easy handling. However, their low mechanical strength, which, in the best of cases, is equal to the trabecular bone, and their very low toughness are disadvantages. Calcium phosphate cement compositions with mechanical properties more closely resembling those of human bone would broaden the range of applications, which is currently limited to sites subjected to low loads. This study investigated the influence of added polypropylene, nylon, and carbon fibers on the mechanical properties of double setting alpha-tricalcium phosphate-based cement, using calcium phosphate cement added to an in situ polymerizable acrylamide-based system recently developed by the authors. Although the addition of fibers was found to reduce the compression strength of the double-setting calcium phosphate cement because of increased porosity, it strongly increased the cement's toughness (J(IC)) and tensile strength. The composites developed in this work, therefore, have a potential application in shapes subjected to flexure. Copyright 2003 Wiley Periodicals, Inc.

A comparison of high viscosity bone cement and low viscosity bone cement vertebroplasty for severe osteoporotic vertebral compression fractures.

PubMed

Zhang, Liang; Wang, Jingcheng; Feng, Xinmin; Tao, Yuping; Yang, Jiandong; Wang, Yongxiang; Zhang, Shengfei; Cai, Jun; Huang, Jijun

2015-02-01

To compare the clinical outcome and complications of high viscosity and low viscosity poly-methyl methacrylate bone cement PVP for severe OVCFs. From December 2010 to December 2012, 32 patients with severe OVCFs were randomly assigned to either group H using high viscosity cement (n=14) or group L using low viscosity cement (n=18). The clinical outcomes were assessed by the Visual Analog Scale (VAS), Oswestry Disability Index (ODI), Short Form-36 General Health Survey (SF-36), kyphosis Cobb's angle, vertebral height, and complications. Significant improvement in the VAS, ODI, SF-36 scores, kyphosis Cobb's angle, and vertebral height were noted in both the groups, and there were no significant differences between the two groups. Cement leakage was seen less in group H. Postoperative assessment using computed tomography identified cement leakage in 5 of 17 (29.4%) vertebrae in group H and in 15 of 22 (68.2%) vertebrae in group L (P=0.025). The PVP using high viscosity bone cement can provide the same clinical outcome and fewer complications compared with PVP using low viscosity bone cement. Copyright © 2014. Published by Elsevier B.V.

Differential osteogenic activity of osteoprogenitor cells on HA and TCP/HA scaffold of tissue engineered bone.

PubMed

Ng, Angela M H; Tan, K K; Phang, M Y; Aziyati, O; Tan, G H; Isa, M R; Aminuddin, B S; Naseem, M; Fauziah, O; Ruszymah, B H I

2008-05-01

Biomaterial, an essential component of tissue engineering, serves as a scaffold for cell attachment, proliferation, and differentiation; provides the three dimensional (3D) structure and, in some applications, the mechanical strength required for the engineered tissue. Both synthetic and naturally occurring calcium phosphate based biomaterial have been used as bone fillers or bone extenders in orthopedic and reconstructive surgeries. This study aims to evaluate two popular calcium phosphate based biomaterial i.e., hydroxyapatite (HA) and tricalcium phosphate/hydroxyapatite (TCP/HA) granules as scaffold materials in bone tissue engineering. In our strategy for constructing tissue engineered bone, human osteoprogenitor cells derived from periosteum were incorporated with human plasma-derived fibrin and seeded onto HA or TCP/HA forming 3D tissue constructs and further maintained in osteogenic medium for 4 weeks to induce osteogenic differentiation. Constructs were subsequently implanted intramuscularly in nude mice for 8 weeks after which mice were euthanized and constructs harvested for evaluation. The differential cell response to the biomaterial (HA or TCP/HA) adopted as scaffold was illustrated by the histology of undecalcified constructs and evaluation using SEM and TEM. Both HA and TCP/HA constructs showed evidence of cell proliferation, calcium deposition, and collagen bundle formation albeit lesser in the former. Our findings demonstrated that TCP/HA is superior between the two in early bone formation and hence is the scaffold material of choice in bone tissue engineering. Copyright 2007 Wiley Periodicals, Inc.

[A study on alpha-tricalcium phosphate bone cement carbon fiber-reinforced].

PubMed

Wu, Wenjin; Yang, Weizhong; Zhou, Dali; Ma, Jiang; Xiao, Bin

2006-06-01

In order to improve the mechanical properties of alpha-tricalcium phosphate (alpha-TCP), we prepared surface-modified carbon fibers (CF) reinforced alpha-TCP composite bone cement. Bone cement was soaked in Ringer's body solution to test its capacity of fast formation of hydroxyapatite crystals and self-solidification. Scan electronic microscope (SEM) observation and compressive strength measurement were taken to analyze the mechanical properties and the micro- morphological structure of CF reinforced alpha-TCP bone cement. The results showed that the bone cement was transferred into hydroxyapatite plates after being soaked in Ringer's simulated body fluid for 5 days. Suitable amount of carbon fibers could well spread in and bond with the matrix of the bone cement. The mechanical properties of the bone cement have been improved by CF reinforcing; the compressive strength reaches 46.7 MPa when the amount of carbon fibers is 0.5% in weight percent, which is 22% higher than that of the non-reinforced alpha-TCP bone cement.

[Significance of bone mineral density and modern cementing technique for in vitro cement penetration in total shoulder arthroplasty].

PubMed

Pape, G; Raiss, P; Kleinschmidt, K; Schuld, C; Mohr, G; Loew, M; Rickert, M

2010-12-01

Loosening of the glenoid component is one of the major causes of failure in total shoulder arthroplasty. Possible risk factors for loosening of cemented components include an eccentric loading, poor bone quality, inadequate cementing technique and insufficient cement penetration. The application of a modern cementing technique has become an established procedure in total hip arthroplasty. The goal of modern cementing techniques in general is to improve the cement-penetration into the cancellous bone. Modern cementing techniques include the cement vacuum-mixing technique, retrograde filling of the cement under pressurisation and the use of a pulsatile lavage system. The main purpose of this study was to analyse cement penetration into the glenoid bone by using modern cement techniques and to investigate the relationship between the bone mineral density (BMD) and the cement penetration. Furthermore we measured the temperature at the glenoid surface before and after jet-lavage of different patients during total shoulder arthroplasty. It is known that the surrounding temperature of the bone has an effect on the polymerisation of the cement. Data from this experiment provide the temperature setting for the in-vitro study. The glenoid surface temperature was measured in 10 patients with a hand-held non-contact temperature measurement device. The bone mineral density was measured by DEXA. Eight paired cadaver scapulae were allocated (n = 16). Each pair comprised two scapulae from one donor (matched-pair design). Two different glenoid components were used, one with pegs and the other with a keel. The glenoids for the in-vitro study were prepared with the bone compaction technique by the same surgeon in all cases. Pulsatile lavage was used to clean the glenoid of blood and bone fragments. Low viscosity bone cement was applied retrogradely into the glenoid by using a syringe. A constant pressure was applied with a modified force sensor impactor. Micro-computed tomography

Developing a novel magnesium glycerophosphate/silicate-based organic-inorganic composite cement for bone repair.

PubMed

Ding, Zhengwen; Li, Hong; Wei, Jie; Li, Ruijiang; Yan, Yonggang

2018-06-01

Considering that the phospholipids and glycerophosphoric acid are the basic materials throughout the metabolism of the whole life period and the bone is composed of organic polymer collagen and inorganic mineral apatite, a novel self-setting composite of magnesium glycerophosphate (MG) and di-calcium silicate(C2S)/tri-calcium silicate(C3S) was developed as bio-cement for bone repair, reconstruction and regeneration. The composite was prepared by mixing the MG, C2S and C3S with the certain ratios, and using the deionized water and phosphoric acid solution as mixed liquid. The combination and formation of the composites was characterized by FTIR, XPS and XRD. The physicochemical properties were studied by setting time, compressive strength, pH value, weight loss in the PBS and surface change by SEM-EDX. The biocompatibility was evaluated by cell culture in the leaching solution of the composites. The preliminary results showed that when di- and tri-calcium silicate contact with water, there are lots of Ca(OH) 2 generated making the pH value of solution is higher than 9 which is helpful for the formation of hydroxyapatite(HA) that is the main bone material. The new organic-inorganic self-setting bio-cements showed initial setting time is ranged from 20 min to 85 min and the compressive strength reached 30 MPa on the 7th days, suitable as the bone fillers. The weight loss was 20% in the first week, and 25% in the 4th week. Meanwhile, the new HA precipitated on the composite surface during the incubation in the SBF showed bioactivity. The cell cultured in the leaching liquid of the composite showed high proliferation inferring the new bio-cement has good biocompatibility to the cells. Copyright © 2018 Elsevier B.V. All rights reserved.

Increased Antibiotic Release from a Bone Cement Containing Bacterial Cellulose

PubMed Central

Nakai, Takahisa; Enomoto, Koichi; Uchio, Yuji; Yoshino, Katsumi

2010-01-01

Background Major disadvantages of antibiotic bone cements include limited drug release and reduced strength resulting from the addition of high doses of antibiotics. Bacterial cellulose, a three-dimensional hydrophilic mesh, may retain antibiotics and release them gradually. We hypothesized that the addition of cellulose to antibiotic bone cement would improve mechanical strength and antibiotic release. Questions/purposes We therefore examined the mechanical strength and antibiotic release of cellulose antibiotic cement. Methods A high dose of antibiotics (5 g per 40 g cement powder) was incorporated into bacterial cellulose and then mixed with bone cement. We compared the compression strength, fracture toughness, fatigue life, and elution kinetics of this formulation with those of plain cement and a traditional antibiotic cement. Results The average values for compression strength, fracture toughness, and fatigue life of the cellulose antibiotic cement were 97%, 97%, and 78% of the values obtained for plain cement, respectively. The corresponding values for the traditional antibiotic cement were 79%, 82%, and 17%, respectively. The cumulative elution over 35 days was 129% greater from the cellulose antibiotic cement than from the traditional antibiotic cement. Conclusions With a high dose of antibiotics, incorporating cellulose into the bone cement prevented compression and fracture fragility, improved fatigue life, and increased antibiotic elution. Clinical Relevance Antibiotic cements containing cellulose may have applications in clinical situations that require high levels of antibiotic release and preservation of the mechanical properties of the cement. PMID:20945120

Calcium phosphate compatible bone cement: Characterization, bonding properties and tissue response

NASA Astrophysics Data System (ADS)

Roemhildt, Maria Lynn

A novel, inorganic, bone cement, containing calcium phosphate, developed for implant fixation was evaluated. Setting properties were determined over a range of temperatures. The flow of the cement was greatly increased by application of vibration. Changes in the cement during hydration and aging were evaluated. Compressive strength of the cement over time was studied under simulated physiological conditions from 1 hour to 1 year after setting. After 1 day, this cement had equivalent compressive strength to commercially used PMMA cement. The strength was found to increase over 1 month and high strength was maintained up to 1 year. The shear strength of the cement-metal interface was studied in vitro using a pull-out test. Prepared specimens were stored under physiological conditions and tested at 4 hours, 24 hours, and 60 days. Comparable interfacial shear strength values were found at 4 hours, 24 hours and 60 days for the experimental cement and were not significantly different from values obtained for PMMA cement. In vivo tissue response was evaluated after cement implantation in the femoral medullary canal in canines. Tissue response and bonding at the cement-bone interface were evaluated at 2, 6, and 12 weeks. Cortical bone was found in direct contact with the OC-cement and was healthy. The strength of the cement-bone interface, measured using a push-out test, was significantly higher for the experimental cement than for commercial PMMA bone cement.

N-acetyl cysteine (NAC)-mediated detoxification and functionalization of poly(methyl methacrylate) bone cement.

PubMed

Tsukimura, Naoki; Yamada, Masahiro; Aita, Hideki; Hori, Norio; Yoshino, Fumihiko; Chang-Il Lee, Masaichi; Kimoto, Katsuhiko; Jewett, Anahid; Ogawa, Takahiro

2009-07-01

Currently used poly(methyl methacrylate) (PMMA)-based bone cement lacks osteoconductivity and induces osteolysis and implant loosening due to its cellular and tissue-toxicity. A high percentage of revision surgery following the use of bone cement has become a significant universal problem. This study determined whether incorporation of the amino acid derivative N-acetyl cysteine (NAC) in bone cement reduces its cytotoxicity and adds osteoconductivity to the material. Biocompatibility and bioactivity of PMMA-based bone cement with or without 25mm NAC incorporation was examined using rat bone marrow-derived osteoblastic cells. Osteoconductive potential of NAC-incorporated bone cement was determined by microCT bone morphometry and implant biomechanical test in the rat model. Generation of free radicals within the polymerizing bone cement was examined using electron spin resonance spectroscopy. Severely compromised viability and completely suppressed phenotypes of osteoblasts on untreated bone cement were restored to the normal level by NAC incorporation. Bone volume formed around 25mm NAC-incorporated bone cement was threefold greater than that around control bone cement. The strength of bone-bone cement integration was 2.2 times greater for NAC-incorporated bone cement. For NAC-incorporated bone cement, the spike of free radical generation ended within 12h, whereas for control bone cement, a peak level lasted for 6 days and a level greater than half the level of the peak was sustained for 20 days. NAC also increased the level of antioxidant glutathione in osteoblasts. These results suggest that incorporation of NAC in PMMA bone cement detoxifies the material by immediate and effective in situ scavenging of free radicals and increasing intracellular antioxidant reserves, and consequently adds osteoconductivity to the material.

A New Biphasic Dicalcium Silicate Bone Cement Implant.

PubMed

Zuleta, Fausto; Murciano, Angel; Gehrke, Sergio A; Maté-Sánchez de Val, José E; Calvo-Guirado, José L; De Aza, Piedad N

2017-07-06

This study aimed to investigate the processing parameters and biocompatibility of a novel biphasic dicalcium silicate (C₂S) cement. Biphasic α´ L + β-C₂S ss was synthesized by solid-state processing, and was used as a raw material to prepare the cement. In vitro bioactivity and biocompatibility studies were assessed by soaking the cement samples in simulated body fluid (SBF) and human adipose stem cell cultures. Two critical-sized defects of 6 mm Ø were created in 15 NZ tibias. A porous cement made of the high temperature forms of C₂S, with a low phosphorous substitution level, was produced. An apatite-like layer covered the cement's surface after soaking in SBF. The cell attachment test showed that α´ L + β-C₂S ss supported cells sticking and spreading after 24 h of culture. The cement paste (55.86 ± 0.23) obtained higher bone-to-implant contact (BIC) percentage values (better quality, closer contact) in the histomorphometric analysis, and defect closure was significant compared to the control group (plastic). The residual material volume of the porous cement was 35.42 ± 2.08% of the initial value. The highest BIC and bone formation percentages were obtained on day 60. These results suggest that the cement paste is advantageous for initial bone regeneration.

Bone remodelling around HA-coated acetabular cups

PubMed Central

Nielsen, P. T.; Søballe, K.

2006-01-01

This study was designed to investigate bone remodelling around the cup in cementless THA. Previous studies indicate an advantage of better sealing of the bone-prosthesis interface by HA/TCP coating of implants, inhibiting polyethylene-induced osteolysis. One hundred patients gave informed consent to participate in a controlled randomized study between porous coated Trilogy versus Trilogy Calcicoat (HA/TCP coated). The cup was inserted in press-fit fixation. The femoral component was a cementless porous coated titanium alloy stem (Bi-Metric), with a modular 28-mm CrCo head. The Harris Hip Score (HHS) and bone mineral density (BMD) determined by DEXA scanning were used to study the effect. Measurements revealed no difference between the two groups after 3 years either in the clinical outcome or in terms of periprosthetic bone density. Patients with a body mass index above normal regained more bone mineral than patients with normal weight. This finding supports the assumption that load is beneficial to bone remodelling. PMID:16761153

Mixing of acrylic bone cement: effect of oxygen on setting properties.

PubMed

He, Shulin; Scott, Christopher; Higham, Paul

2003-12-01

The present study investigates the effect of different mixing methods on the setting properties of bone cement. It was found that vacuum mixing decreased the setting time of the bone cement by nearly 2 min (10%), compared to mixing in air. Two additional experiments, in which the bone cement powders were purged with argon or oxygen, and mixed with the methyl methacrylate monomer, revealed that oxygen concentrations in the bone cement had a great effect on the setting time. The setting time increases significantly as the oxygen concentration increases, which suggests that the decrease in the setting time by vacuum mixing may be attributed to the lower oxygen levels present in the mixer. No significant effect was observed on dough time or maximum exothermic temperature by varying oxygen concentrations in the bone cement mixer.

A New Biphasic Dicalcium Silicate Bone Cement Implant

PubMed Central

Murciano, Angel; Maté-Sánchez de Val, José E.

2017-01-01

This study aimed to investigate the processing parameters and biocompatibility of a novel biphasic dicalcium silicate (C2S) cement. Biphasic α´L + β-C2Sss was synthesized by solid-state processing, and was used as a raw material to prepare the cement. In vitro bioactivity and biocompatibility studies were assessed by soaking the cement samples in simulated body fluid (SBF) and human adipose stem cell cultures. Two critical-sized defects of 6 mm Ø were created in 15 NZ tibias. A porous cement made of the high temperature forms of C2S, with a low phosphorous substitution level, was produced. An apatite-like layer covered the cement’s surface after soaking in SBF. The cell attachment test showed that α´L + β-C2Sss supported cells sticking and spreading after 24 h of culture. The cement paste (55.86 ± 0.23) obtained higher bone-to-implant contact (BIC) percentage values (better quality, closer contact) in the histomorphometric analysis, and defect closure was significant compared to the control group (plastic). The residual material volume of the porous cement was 35.42 ± 2.08% of the initial value. The highest BIC and bone formation percentages were obtained on day 60. These results suggest that the cement paste is advantageous for initial bone regeneration. PMID:28773119

Analysis of rheological properties of bone cements.

PubMed

Nicholas, M K D; Waters, M G J; Holford, K M; Adusei, G

2007-07-01

The rheological properties of three commercially available bone cements, CMW 1, Palacos R and Cemex ISOPLASTIC, were investigated. Testing was undertaken at both 25 and 37 degrees C using an oscillating parallel plate rheometer. Results showed that the three high viscosity cements exhibited distinct differences in curing rate, with CMW 1 curing in 8.7 min, Palacos R and Cemex ISOPLASTIC in 13 min at 25 degrees C. Furthermore it was found that these curing rates were strongly temperature dependent, with curing rates being halved at 37 degrees C. By monitoring the change of viscosity with time over the entire curing process, the results showed that these cements had differing viscosity profiles and hence exhibit very different handling characteristics. However, all the cements reached the same maximum viscosity of 75 x 10(3) Pa s. Also, the change in elastic/viscous moduli and tan delta with time, show the cements changing from a viscous material to an elastic solid with a clear peak in the viscous modulus during the latter stages of curing. These results give valuable information about the changes in rheological properties for each commercial bone cement, especially during the final curing process.

Creep and fatigue behavior of a novel 2-component paste-like formulation of acrylic bone cements.

PubMed

Köster, Ulrike; Jaeger, Raimund; Bardts, Mareike; Wahnes, Christian; Büchner, Hubert; Kühn, Klaus-Dieter; Vogt, Sebastian

2013-06-01

The fatigue and creep performance of two novel acrylic bone cement formulations (one bone cement without antibiotics, one with antibiotics) was compared to the performance of clinically used bone cements (Osteopal V, Palacos R, Simplex P, SmartSet GHV, Palacos R+G and CMW1 with Gentamicin). The preparation of the novel bone cement formulations involves the mixing of two paste-like substances in a static mixer integrated into the cartridge which is used to apply the bone cement. The fatigue performance of the two novel bone cement formulations is comparable to the performance of the reference bone cements. The creep compliance of the bone cements is significantly influenced by the effects of physical ageing. The model parameters of Struik's creep law are used to compare the creep behavior of different bone cements. The novel 2-component paste-like bone cement formulations are in the group of bone cements which exhibit a higher creep resistance.

Influence of bone density on the cement fixation of femoral hip resurfacing components.

PubMed

Bitsch, Rudi G; Jäger, Sebastian; Lürssen, Marcus; Loidolt, Travis; Schmalzried, Thomas P; Clarius, Michael

2010-08-01

In clinical outcome studies, small component sizes, female gender, femoral shape, focal bone defects, bad bone quality, and biomechanics have been associated with failures of resurfacing arthroplasties. We used a well-established experimental setup and human bone specimens to analyze the effects of bone density on cement fixation of femoral hip resurfacing components. Thirty-one fresh frozen femora were prepared for resurfacing using the original instruments. ASR resurfacing prostheses were implanted after dual-energy X-ray densitometer scans. Real-time measurements of pressure and temperature during implantation, analyses of cement penetration, and measurements of micro motions under torque application were performed. The associations of bone density and measurement data were examined calculating regression lines and multiple correlation coefficients; acceptability was tested with ANOVA. We found significant relations between bone density and micro motion, cement penetration, cement mantle thickness, cement pressure, and interface temperature. Mean bone density of the femora was 0.82 +/- 0.13 g/cm(2), t-score was -0.7 +/- 1.0, and mean micro motion between bone and femoral resurfacing component was 17.5 +/- 9.1 microm/Nm. The regression line between bone density and micro motion was equal to -56.7 x bone density + 63.8, R = 0.815 (p < 0.001). Bone density scans are most helpful for patient selection in hip resurfacing, and a better bone quality leads to higher initial component stability. A sophisticated cementing technique is recommended to avoid vigorous impaction and incomplete seating, since increasing bone density also results in higher cement pressures, lower cement penetration, lower interface temperatures, and thicker cement mantles. Copyright 2010 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

Development of monetite-nanosilica bone cement: a preliminary study.

PubMed

Zhou, Huan; Luchini, Timothy J F; Agarwal, Anand K; Goel, Vijay K; Bhaduri, Sarit B

2014-11-01

In this paper, we reported the results of our efforts in developing DCPA/nanosilica composite orthopedic cement. It is motivated by the significances of DCPA and silicon in bone physiological activities. More specifically, this paper examined the effects of various experimental parameters on the properties of such composite cements. In this work, DCPA cement powders were synthesized using a microwave synthesis technique. Mixing colloidal nanosilica directly with synthesized DCPA cement powders can significantly reduce the washout resistance of DCPA cement. In contrast, a DCPA-nanosilica cement powder prepared by reacting Ca(OH)2 , H3 PO4 and nanosilica together showed good washout resistance. The incorporation of nanosilica in DCPA can improve compressive strength, accelerate cement solidification, and intensify surface bioactivity. In addition, it was observed that by controlling the content of NaHCO3 during cement preparation, the resulting composite cement properties could be modified. Allowing for the development of different setting times, mechanical performance and crystal features. It is suggested that DCPA-nanosilica composite cement can be a potential candidate for bone healing applications. © 2014 Wiley Periodicals, Inc.

Development of high-viscosity, two-paste bioactive bone cements.

PubMed

Deb, S; Aiyathurai, L; Roether, J A; Luklinska, Z B

2005-06-01

Self-curing two-paste bone cements have been developed using methacrylate monomers with a view to formulate cements with low polymerization exotherm, low shrinkage, better mechanical properties, and improved adhesion to bone and implant surfaces. The monomers include bis-phenol A glycidyl dimethacrylate (bis-GMA), urethane dimethacrylate (UDMA) and triethylene glycol dimethacrylate (TEGDMA) as a viscosity modifier. Two-paste systems were formulated containing 60% by weight of a bioactive ceramic, hydroxyapatite. A methacroyloxy silane (A174) was used as a coupling agent due to its higher water stability in comparison to other aminosilanes to silanate the hydroxyapatite particles prior to composite formulation. A comparison of the FT-infrared spectrum of hydroxyapatite and silanated hydroxyapatite showed the presence of the carbonyl groups ( approximately 1720 cm(-1)), -C=C-( approximately 1630 cm(-1)) and Si-O- (1300-1250 cm(-1)) which indicated the availability of silane groups on the filler surface. Two methods of mixing were effected to form the bone cement: firstly by mixing in an open bowl and secondly by extruding the two pastes by an auto-mixing tip using a gun to dispense the pastes. Both types of cements yielded low polymerization exotherms with good mechanical properties; however, the lower viscosity of UDMA allowed better extrusion and handling properties. A biologically active apatite layer formed on the bone cement surface within a short period after its immersion in simulated body fluid, demonstrating in vitro bioactivity of the composite. This preliminary data thus suggests that UDMA is a viable alternative to bis-GMA as a polymerizable matrix in the formation of bone cements.

Polymethylmethacrylate bone cements and additives: A review of the literature

PubMed Central

Arora, Manit; Chan, Edward KS; Gupta, Sunil; Diwan, Ashish D

2013-01-01

Polymethylmethacrylate (PMMA) bone cement technology has progressed from industrial Plexiglass administration in the 1950s to the recent advent of nanoparticle additives. Additives have been trialed to address problems with modern bone cements such as the loosening of prosthesis, high post-operative infection rates, and inflammatory reduction in interface integrity. This review aims to assess current additives used in PMMA bone cements and offer an insight regarding future directions for this biomaterial. Low index (< 15%) vitamin E and low index (< 5 g) antibiotic impregnated additives significantly address infection and inflammatory problems, with only modest reductions in mechanical strength. Chitosan (15% w/w PMMA) and silver (1% w/w PMMA) nanoparticles have strong antibacterial activity with no significant reduction in mechanical strength. Future work on PMMA bone cements should focus on trialing combinations of these additives as this may enhance favourable properties. PMID:23610754

Bone regeneration capacity of magnesium phosphate cements in a large animal model.

PubMed

Kanter, Britta; Vikman, Anna; Brückner, Theresa; Schamel, Martha; Gbureck, Uwe; Ignatius, Anita

2018-03-15

Magnesium phosphate minerals have captured increasing attention during the past years as suitable alternatives for calcium phosphate bone replacement materials. Here, we investigated the degradation and bone regeneration capacity of experimental struvite (MgNH 4 PO 4 ·6H 2 O) forming magnesium phosphate cements in two different orthotopic ovine implantation models. Cements formed at powder to liquid ratios (PLR) of 2.0 and 3.0 g ml -1 were implanted into trabecular bone using a non-load-bearing femoral drill-hole model and a load-bearing tibial defect model. After 4, 7 and 10 months the implants were retrieved and cement degradation and new bone formation was analyzed by micro-computed tomography (µCT) and histomorphometry. The results showed cement degradation in concert with new bone formation at both defect locations. Both cements were almost completely degraded after 10 months. The struvite cement formed with a PLR of 2.0 g ml -1 exhibited a slightly accelerated degradation kinetics compared to the cement with a PLR of 3.0 g ml -1 . Tartrat-resistant acid phosphatase (TRAP) staining indicated osteoclastic resorption at the cement surface. Energy dispersive X-ray analysis (EDX) revealed that small residual cement particles were mostly accumulated in the bone marrow in between newly formed bone trabeculae. Mechanical loading did not significantly increase bone formation associated with cement degradation. Concluding, struvite-forming cements might be promising bone replacement materials due to their good degradation which is coupled with new bone formation. Recently, the interest in magnesium phosphate cements (MPC) for bone substitution increased, as they exhibit high initial strength, comparably elevated degradation potential and the release of valuable magnesium ions. However, only few in vivo studies, mostly including non-load-bearing defects in small animals, have been performed to analyze the degradation and regeneration capability of MPC

Bone density and anisotropy affect periprosthetic cement and bone stresses after anatomical glenoid replacement: A micro finite element analysis.

PubMed

Chevalier, Yan; Santos, Inês; Müller, Peter E; Pietschmann, Matthias F

2016-06-14

Glenoid loosening is still a main complication for shoulder arthroplasty. We hypothesize that cement and bone stresses potentially leading to fixation failure are related not only to glenohumeral conformity, fixation design or eccentric loading, but also to bone volume fraction, cortical thickness and degree of anisotropy in the glenoid. In this study, periprosthetic bone and cement stresses were computed with micro finite element models of the replaced glenoid depicting realistic bone microstructure. These models were used to quantify potential effects of bone microstructural parameters under loading conditions simulating different levels of glenohumeral conformity and eccentric loading simulating glenohumeral instability. Results show that peak cement stresses were achieved near the cement-bone interface in all loading schemes. Higher stresses within trabecular bone tissue and cement mantle were obtained within specimens of lower bone volume fraction and in regions of low anisotropy, increasing with decreasing glenohumeral conformity and reaching their maxima below the keeled design when the load is shifted superiorly. Our analyses confirm the combined influences of eccentric load shifts with reduced bone volume fraction and anisotropy on increasing periprosthetic stresses. They finally suggest that improving fixation of glenoid replacements must reduce internal cement and bone tissue stresses, in particular in glenoids of low bone density and heterogeneity. Copyright © 2016 Elsevier Ltd. All rights reserved.

Preparation and Characterization of Injectable Brushite Filled-Poly (Methyl Methacrylate) Bone Cement

PubMed Central

Rodriguez, Lucas C.; Chari, Jonathan; Aghyarian, Shant; Gindri, Izabelle M.; Kosmopoulos, Victor; Rodrigues, Danieli C.

2014-01-01

Powder-liquid poly (methyl methacrylate) (PMMA) bone cements are widely utilized for augmentation of bone fractures and fixation of orthopedic implants. These cements typically have an abundance of beneficial qualities, however their lack of bioactivity allows for continued development. To enhance osseointegration and bioactivity, calcium phosphate cements prepared with hydroxyapatite, brushite or tricalcium phosphates have been introduced with rather unsuccessful results due to increased cement viscosity, poor handling and reduced mechanical performance. This has limited the use of such cements in applications requiring delivery through small cannulas and in load bearing. The goal of this study is to design an alternative cement system that can better accommodate calcium-phosphate additives while preserving cement rheological properties and performance. In the present work, a number of brushite-filled two-solution bone cements were prepared and characterized by studying their complex viscosity-versus-test frequency, extrusion stress, clumping tendency during injection through a syringe, extent of fill of a machined void in cortical bone analog specimens, and compressive strength. The addition of brushite into the two-solution cement formulations investigated did not affect the pseudoplastic behavior and handling properties of the materials as demonstrated by rheological experiments. Extrusion stress was observed to vary with brushite concentration with values lower or in the range of control PMMA-based cements. The materials were observed to completely fill pre-formed voids in bone analog specimens. Cement compressive strength was observed to decrease with increasing concentration of fillers; however, the materials exhibited high enough strength for consideration in load bearing applications. The results indicated that partially substituting the PMMA phase of the two-solution cement with brushite at a 40% by mass concentration provided the best combination of the

Bone preserving techniques for explanting the well-fixed cemented acetabular component.

PubMed

Stevens, Jarrad; Macpherson, Gavin; Howie, Colin

2018-06-01

Removal of a well-fixed, cemented acetabular component at the time of revision hip surgery can be complex. It is essential to remove the implant and cement mantle in a timely fashion while preserving bone stock and osseous integrity. The biomechanical properties of polymethylmethacrylate cement and polyethylene can be utilised to aid with the removal of well cemented implants which are often harder than the surrounding bone. While removal of loose components may be relatively straightforward, the challenge for the revision arthroplasty surgeon often involves the removal of well-fixed implants. Here, we present three established techniques for the removal of a well-fixed cemented acetabular component and one novel modification we have described before. We collate and review four techniques for removing well-fixed cemented acetabular implants that utilise the different biomechanical properties of bone cement and polyethylene. These techniques are illustrated with a photographic series utilising saw bones. A step-by-step approach to our new technique is shown in photographs, both in the clinical setting and with a "Sawbone". This is accompanied by a clinical video that details the surgical technique in its entirety. These techniques utilise different biomechanical principles to extract the acetabular component. Each technique has advantages and disadvantages. Our new technique is a simplification of a previously published extraction manoeuvre that utilises tensile force between cement and the implant to remove the polyethylene cup. This is a safe and reproducible technique in patients with a well-fixed cemented acetabular implant. Understanding the biomechanical properties of polymethylmethacrylate bone cement and polyethylene can aid in the safe removal of a well-fixed cemented acetabular component in revision hip surgery. The optimal technique for removal of a cemented acetabular component varies depending on a number of patient and implant factors. This summary of

Micro-mechanical damage of trabecular bone-cement interface under selected loading conditions: a finite element study.

PubMed

Zhang, Qing-Hang; Tozzi, Gianluca; Tong, Jie

2014-01-01

In this study, two micro finite element models of trabecular bone-cement interface developed from high resolution computed tomography (CT) images were loaded under compression and validated using the in situ experimental data. The models were then used under tension and shear to examine the load transfer between the bone and cement and the micro damage development at the bone-cement interface. In addition, one models was further modified to investigate the effect of cement penetration on the bone-cement interfacial behaviour. The simulated results show that the load transfer at the bone-cement interface occurred mainly in the bone cement partially interdigitated region, while the fully interdigitated region seemed to contribute little to the mechanical response. Consequently, cement penetration beyond a certain value would seem to be ineffective in improving the mechanical strength of trabecular bone-cement interface. Under tension and shear loading conditions, more cement failures were found in denser bones, while the cement damage is generally low under compression.

In vivo response of bioactive PMMA-based bone cement modified with alkoxysilane and calcium acetate.

PubMed

Sugino, Atsushi; Ohtsuki, Chikara; Miyazaki, Toshiki

2008-11-01

The use of polymethylmethacrylate (PMMA)-based bone cement is popular in orthopedics for the fixation of artificial joints with bone. However, it has a major problem with prostheses loosening because of coverage by fibrous tissue after long-term implantation. Recently, a bioactive bone cement has been developed that shows direct bonding to living bone through modification of PMMA resin with gamma-methacryloxypropyltrimethoxysilane (MPS) and calcium acetate. The cement is designed to exhibit bioactivity, through incorporation of silanol groups and calcium ions. Thus, it has the potential to form a layer of bone-like hydroxyapatite, which is essential for achieving direct bonding to living bone. This type of modification allows the cement to show spontaneous hydroxyapatite formation on its surface in a simulated body fluid after one day, and there is evidence of osteoconduction of the cement in rabbit tibia for periods of more than three weeks. However, the influence of the dissolved ions from the modified cement has not yet been clarified. Thus, the authors focused on the dissolution of the modified PMMA-based bone cement and its tissue response in muscle and bone by comparison with the behavior of non-modified PMMA-based bone cement. One week after implantation in the latissimus dorsi of a rabbit, the modified PMMA-based bone cement showed more inflammatory width than the commercial cement. However, four weeks after implantation, the inflammatory width of both cements was essentially the same. The osteoconductivity around the modified cement was higher than that for the conventional cement after four weeks implantation. These results indicate that the initial dissolution of calcium acetate from the modified cement to form the hydroxyapatite induced the acute inflammation around tissue, but also developed the osteoconductivity. It is suggested that the initial inflammation can be effective for inducing osteoconduction through a bone healing reaction when the

[Experiment of porous calcium phosphate/bone matrix gelatin composite cement for repairing lumbar vertebral bone defect in rabbit].

PubMed

Wang, Song; Yang, Han; Yang, Jian; Kang, Jianping; Wang, Qing; Song, Yueming

2017-12-01

To investigate the effect of a porous calcium phosphate/bone matrix gelatin (BMG) composite cement (hereinafter referred to as the "porous composite cement") for repairing lumbar vertebral bone defect in a rabbit model. BMG was extracted from adult New Zealand rabbits according to the Urist's method. Poly (lactic-co-glycolic) acid (PLGA) microsphere was prepared by W/O/W double emulsion method. The porous composite cement was developed by using calcium phosphate cement (CPC) composited with BMG and PLGA microsphere. The physicochemical characterizations of the porous composite cement were assessed by anti-washout property, porosity, and biomechanical experiment, also compared with the CPC. Thirty 2-month-old New Zealand rabbits were used to construct vertebral bone defect at L 3 in size of 4 mm×3 mm×3 mm. Then, the bone defect was repaired with porous composite cement (experimental group, n =15) or CPC (control group, n =15). At 4, 8, and 12 weeks after implantation, each bone specimen was assessed by X-ray films for bone fusion, micro-CT for bone mineral density (BMD), bone volume fraction (BVF), trabecular thickness (Tb. Th.), trabecular number (Tb.N.), and trabecular spacing (Tb. Sp.), and histological section with toluidine blue staining for new-born bone formation. The study demonstrated well anti-washout property in 2 groups. The porous composite cement has 55.06%±1.18% of porosity and (51.63±6.73) MPa of compressive strength. The CPC has 49.38%±1.75% of porosity and (63.34±3.27) MPa of compressive strength. There were significant differences in porosity and compressive strength between different cements ( t =4.254, P =0.006; t =2.476, P =0.034). X-ray films revealed that the zone between the cement and host bone gradually blurred with the time extending. At 12 weeks after implantation, the zone was disappeared in the experimental group, but clear in the control group. There were significant differences in BMD, BVF, Tb. Th., Tb. N., and Tb. Sp. between

Preparation of Calcium Phosphate Cement and Polymethyl Methacrylate for Biological Composite Bone Cements

PubMed Central

Yang, Jun; Zhang, Kairui; Zhang, Sheng; Fan, Jiping; Guo, Xinhui; Dong, Weiqiang; Wang, Shengnan; Chen, Yirong; Yu, Bin

2015-01-01

Background We studied the biological safety, biomechanics, and tissue compatibility of calcium phosphate cement and Polymethyl Methacrylate composite bone cement mixed in different ratios. Material/Methods CPC and PMMA were mixed in different ratios (3: 1, 2: 1, 1: 1, 1: 2, 1: 5, 1: 10, 1: 15, and 1: 20). PMMA solvent is a general solvent containing a dissolved preparation of the composite bone cement specific to a given specimen to determine biological safety, biomechanics, and tissue compatibility. Results The CPC/PMMA (33%) group, CPC/PMMA (50%) group, CPC/PMMA (67%) group, and CPC/PMMA (75%) group were more in line with the composite bone cement without cytotoxicity requirements. The compressive strength of the CPC/PMMA (67%) group and CPC/PMMA (75%) group was 20Mpa–30Mpa, while that of the CPC/PMMA (4.8%) group, CPC/PMMA (6.25%) group, CPC/PMMA (9.1%) group, CPC/PMMA (16.7%) group, CPC/PMMA (33%) group, and CPC/PMMA (50%) group was 40Mpa–70Mpa. Curing time was longer in the CPC group (more than 11 min) and shorter in the PMMA group (less than 2 min). The results of weight loss rate showed that there were no significant differences between the CPC/PMMA group (4.8%, 6.25%, 9.1%, 16.7%, 33%) and PMMA control group (p>0.05). With the decrease of CPC content, the rate of weight loss gradually decreased. Conclusions The CPC/PMMA (50%) group, CPC/PMMA (67%) group, and CPC/PMMA (75%) group provide greater variability and selectivity for the composite bone cement in obtaining better application. PMID:25904398

In vivo performance of a reduced-modulus bone cement

NASA Astrophysics Data System (ADS)

Forehand, Brett Ramsey

Total joint replacement has become one of the most common procedures in the area of orthopedics and is often the solution in patients with diseased or injured hip joints. Component loosening is a significant problem and is primarily caused by bone resorption at the bone-cement interface in cemented implants. It is our hypothesis that localized shear stresses are responsible for the resorption. It was previously shown analytically that local stresses at the interface could be reduced by using a cement of lower modulus. A new reduced modulus cement, polybutyl methylmethacrylate (PBMMA), was developed to test the hypothesis. PBMMA was formulated to exist as polybutyl methacrylate filler in a polymethyl methacrylate matrix. The success of PBMMA cement is based largely on the fact that the polybutyl component of the cement will be in the rubbery state at body temperature. In vitro characterization of the cement was undertaken previously and demonstrated a modulus of approximately one-eighth that of conventional bone cement, polymethyl methacrylate (PMMA) and increased fracture toughness. The purpose of this experiment was to perform an in vivo comparison of the two cements. A sheep model was selected. Total hip arthroplasty was performed on 50 ewes using either PBMMA or PMMA. Radiographs were taken at 6 month intervals. At one year, the contralateral femur of each sheep was implanted so that each animal served as its own control, and the animals were sacrificed. The stiffness of the bone-cement interface of the femoral component within the femur was assessed by applying a torque to the femoral component and demonstrated a significant difference in loosening between the cements when the specimens were tested in external rotation (p < 0.007). Evaluation of the mechanical data also suggests that the PBMMA sheep had a greater amount of loosening for each subject, 59% versus 4% for standard PMMA. A radiographic analysis demonstrated more signs of loosening in the PMMA series

[The injection of acrylic bone cement prevents bone collapse in the intercalar bones lacking bony support: an experimental sheep semilunar bone model].

PubMed

Unsal, Murat; Tetik, Cihangir; Erol, Bülent; Cabukoğlu, Cengiz

2003-01-01

In a sheep semilunar bone model, we investigated whether collapse in the intercalar bones lacking bony support could be prevented by the injection of acrylic bone cement. The study included 16 limbs of eight sheep. Preoperatively, anteroposterior and lateral views of the carpal joints in the fore limbs were obtained. The animals were divided into four groups. In group 1 (n=3) no surgical procedure was performed in the right semilunar bones, whereas the periosteum on the contralateral side was elevated (group 2; n=3). The first two groups were left as controls. In Group 3 (n=5) the left semilunar bones were filled with acrylic bone cement following decancellation of the bone, while the right semilunar bones were left decancellated (group 4; n=5). The sheep were monitored for three months. Radiographs of the carpal joints were obtained to evaluate collapse occurrence in the semilunar bones. Thereafter, the animals were sacrificed and the semilunar bones were excised for biomechanical and histological examinations. Osteonecrosis and cartilage damage were sought and resistance to compressive forces was investigated. Radiologically, the extent of collapse was statistically significant in the semilunar bones in group 4 (p<0.05). The use of acrylic bone cement was found to prevent collapse in group 3, with no significant difference being noted between preoperative and postoperative semilunar bone heights (p>0.05). Biomechanically, the least resistance to compressive forces was measured in group 4 (p<0.05). Histologically, cartilage damage and osteonecrosis were only seen in group 4. Our data suggest that the use of acrylic bone cement prevents collapse in the semilunar bones, without inducing any cartilage damage or osteonecrosis.

Method of adhering bone to a rigid substrate using a graphite fiber reinforced bone cement

NASA Technical Reports Server (NTRS)

Knoell, A. C.; Maxwell, H. G. (Inventor)

1977-01-01

A method is described for adhering bone to the surface of a rigid substrate such as a metal or resin prosthesis using an improved surgical bone cement. The bone cement has mechanical properties more nearly matched to those of animal bone and thermal curing characteristics which result in less traumatization of body tissues and comprises a dispersion of short high modulus graphite fibers within a bonder composition including polymer dissolved in reactive monomer such as polymethylmethacrylate dissolved in methylmethacrylate monomer.

The effect of N-acetylcysteine on mechanical fatigue resistance of antibiotic-loaded bone cement.

PubMed

Sukur, Erhan; Akar, Abdulhalim; Topcu, Huseyin Nevzat; Cicekli, Ozgur; Kochai, Alauddin; Turker, Mehmet

2018-05-31

This biomechanical study evaluates the effect of N-acetylcysteine alone and in combination with the most commonly used antibiotic-loaded bone cement mixtures. We mixed eight bone cement mixture groups including combinations of N-acetylcysteine, gentamicin, teicoplanin, and vancomycin and applied a four-point bending test individually to each sample on days 1 and 15 using an MTS Acumen test device. The result was less than 50 MPa-the limit declared by the ISO (International Standards Organization)-in only the "gentamicin + bone cement + N-acetylcysteine" group. Mechanical fatigue resistance of the bone cement decreased significantly with the addition of N-acetylcysteine both on day 1 and day 15 (p <  0.001). With the addition of N-acetylcysteine into the "gentamicin + bone cement" and "vancomycin + bone cement" mixtures, a significant decrease in mechanical fatigue resistance was observed both on day 1 and day 15 (p <  0.001). In contrast, with the addition of N-acetylcysteine into the "teicoplanin + bone cement" mixture, no significant difference in mechanical fatigue resistance was observed on days 1 and 15 (p = 0.093, p = 0.356). Preliminary results indicate that adding N-acetylcysteine to teicoplanin-loaded bone cement does not significantly affect the cement's mechanical resistance, potentially leading to a new avenue for preventing and treating peri-prosthetic joint infection. N-acetylcysteine may, therefore, be considered as an alternative agent to be added to antibiotic-loaded bone cement mixtures used in the prevention of peri-prosthetic joint infection.

Does bone cement in percutaneous vertebroplasty act as a stress riser?

PubMed

Aquarius, René; van der Zijden, Astrid Maria; Homminga, Jasper; Verdonschot, Nico; Tanck, Esther

2013-11-15

An in vitro cadaveric study. To determine whether percutaneous vertebroplasty (PVP) with a clinically relevant amount of bone cement is capable of causing stress peaks in adjacent-level vertebrae. It is often suggested that PVP of a primary spinal fracture causes stress peaks in adjacent vertebrae, thereby leading to additional fractures. The in vitro studies that demonstrated this relationship, however, use bigger volumes of bone cement used clinically. Ten fresh-frozen vertebrae were loaded until failure, while registering force and displacement as well as the pressure under the lower endplate. After failure, the vertebrae were augmented with clinically relevant amounts of bone cement and then again loaded until failure. The force, displacement, and pressure under the lower endplate were again registered. Stress peaks were not related to the location of the injected bone cement. Both failure load and stiffness were significantly lower after augmentation. On the basis of our findings, we conclude that vertebral augmentation with clinically relevant amounts of bone cement does not lead to stress peaks under the endplate. It is therefore unlikely that PVP, in itself, causes detrimental stresses in the adjacent vertebrae, leading to new vertebral fractures. N/A.

A Particle Model for Prediction of Cement Infiltration of Cancellous Bone in Osteoporotic Bone Augmentation.

PubMed

Basafa, Ehsan; Murphy, Ryan J; Kutzer, Michael D; Otake, Yoshito; Armand, Mehran

2013-01-01

Femoroplasty is a potential preventive treatment for osteoporotic hip fractures. It involves augmenting mechanical properties of the femur by injecting Polymethylmethacrylate (PMMA) bone cement. To reduce the risks involved and maximize the outcome, however, the procedure needs to be carefully planned and executed. An important part of the planning system is predicting infiltration of cement into the porous medium of cancellous bone. We used the method of Smoothed Particle Hydrodynamics (SPH) to model the flow of PMMA inside porous media. We modified the standard formulation of SPH to incorporate the extreme viscosities associated with bone cement. Darcy creeping flow of fluids through isotropic porous media was simulated and the results were compared with those reported in the literature. Further validation involved injecting PMMA cement inside porous foam blocks - osteoporotic cancellous bone surrogates - and simulating the injections using our proposed SPH model. Millimeter accuracy was obtained in comparing the simulated and actual cement shapes. Also, strong correlations were found between the simulated and the experimental data of spreading distance (R(2) = 0.86) and normalized pressure (R(2) = 0.90). Results suggest that the proposed model is suitable for use in an osteoporotic femoral augmentation planning framework.

Optimisation of a two-liquid component pre-filled acrylic bone cement system: a design of experiments approach to optimise cement final properties.

PubMed

Clements, James; Walker, Gavin; Pentlavalli, Sreekanth; Dunne, Nicholas

2014-10-01

The initial composition of acrylic bone cement along with the mixing and delivery technique used can influence its final properties and therefore its clinical success in vivo. The polymerisation of acrylic bone cement is complex with a number of processes happening simultaneously. Acrylic bone cement mixing and delivery systems have undergone several design changes in their advancement, although the cement constituents themselves have remained unchanged since they were first used. This study was conducted to determine the factors that had the greatest effect on the final properties of acrylic bone cement using a pre-filled bone cement mixing and delivery system. A design of experiments (DoE) approach was used to determine the impact of the factors associated with this mixing and delivery method on the final properties of the cement produced. The DoE illustrated that all factors present within this study had a significant impact on the final properties of the cement. An optimum cement composition was hypothesised and tested. This optimum recipe produced cement with final mechanical and thermal properties within the clinical guidelines and stated by ISO 5833 (International Standard Organisation (ISO), International standard 5833: implants for surgery-acrylic resin cements, 2002), however the low setting times observed would not be clinically viable and could result in complications during the surgical technique. As a result further development would be required to improve the setting time of the cement in order for it to be deemed suitable for use in total joint replacement surgery.

Strain-controlled fatigue of acrylic bone cement.

PubMed

Carter, D R; Gates, E I; Harris, W H

1982-09-01

Monotonic tensile tests and tension-compression fatigue tests were conducted of wet acrylic bone cement specimens at 37 degrees C. All testing was conducted in strain control at a strain rate of 0.02/s. Weibull analysis of the tensile tests indicated that monotonic fracture was governed more strongly by strain than stress. The number of cycles to fatigue failure was also more strongly controlled by strain amplitude than stress amplitude. Specimen porosity distribution played a major role in determining the tensile and fatigue strengths. The degree of data scatter suggests that Weibull analysis of fatigue data may be useful in developing design criteria for the surgical use of bone cement.

Proton Range Uncertainty Due to Bone Cement Injected Into the Vertebra in Radiation Therapy Planning

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lim, Young Kyung; Hwang, Ui-Jung; Shin, Dongho, E-mail: dongho@ncc.re.kr

2011-10-01

We wanted to evaluate the influence of bone cement on the proton range and to derive a conversion factor predicting the range shift by correcting distorted computed tomography (CT) data as a reference to determine whether the correction is needed. Two CT datasets were obtained with and without a bone cement disk placed in a water phantom. Treatment planning was performed on a set of uncorrected CT images with the bone cement disk, and the verification plan was applied to the same set of CT images with an effective CT number for the bone cement disk. The effective CT numbermore » was determined by measuring the actual proton range with the bone cement disk. The effects of CT number, thicknesses, and position of bone cement on the proton range were evaluated in the treatment planning system (TPS) to draw a conversion factor predicting the range shift by correcting the CT number of bone cement. The effective CT number of bone cement was 260 Hounsfield units (HU). The calculated proton range for native CT data was significantly shorter than the measured proton range. However, the calculated range for the corrected CT data with the effective CT number coincided exactly with the measured range. The conversion factor was 209.6 [HU . cm/mm] for bone cement and predicted the range shift by approximately correcting the CT number. We found that the heterogeneity of bone cement could cause incorrect proton ranges in treatment plans using CT images. With an effective CT number of bone cement derived from the proton range and relative stopping power, a more actual proton range could be calculated in the TPS. The conversion factor could predict the necessity for CT data correction with sufficient accuracy.« less

The Biomechanical Properties of Pedicle Screw Fixation Combined With Trajectory Bone Cement Augmentation in Osteoporotic Vertebrae.

PubMed

Fan, Haitao T; Zhang, Renjie J; Shen, Cailiang L; Dong, Fulong L; Li, Yong; Song, Peiwen W; Gong, Chen; Wang, Yijin J

2016-03-01

The biomechanics of pedicle screw fixation combined with trajectory cement augmentation with various filling volumes were measured by pull-out, periodic antibending, and compression fatigue tests. To investigate the biomechanical properties of the pedicle screw fixation combined with trajectory bone cement (polymethylmethacrylate) augmentation in osteoporotic vertebrae and to explore the optimum filling volume of the bone cement. Pedicle screw fixation is considered to be the most effective posterior fixation method. The decrease of the bone mineral density apparently increases the fixation failure risk caused by screw loosening and displacement. Trajectory bone cement augmentation has been confirmed to be an effective method to increase the bone intensity and could markedly increase the stability of the fixation interface. Sixteen elderly cadaveric 1-5 lumbar vertebral specimens were diagnosed with osteoporosis. The left and right vertebral pedicles were alternatively randomized for treatment in all groups, with the contralateral pedicles as control. The study groups included: group A (pedicle screw fixation with full trajectory bone cement augmentation), group B (75% filling), group C (50% filling), and group D (25% filling). Finally, the bone cement leakage and dispersion were assessed and the mechanical testing was conducted. The bone cement was well dispersed around the pedicle screw. The augmented bone intensity, pull-out strength, periodic loading times, and compression fatigue performance were markedly higher than those of the control groups. With the increase in trajectory bone cement, the leakage was also increased (P<0.05). The pull-out strength of the pedicle screw was increased with an increase in bone mineral density and trajectory bone cement. It peaked at 75% filling, with the largest power consumption. The optimal filling volume of the bone cement was 75% of the trajectory volume (about 1.03 mL). The use of excessive bone cement did not increase

Evaluation of four biodegradable, injectable bone cements in an experimental drill hole model in sheep.

PubMed

von Rechenberg, Brigitte; Génot, Oliver R; Nuss, Katja; Galuppo, Larry; Fulmer, Mark; Jacobson, Evan; Kronen, Peter; Zlinszky, Kati; Auer, Jörg A

2013-09-01

Four cement applications were tested in this investigation. Two dicalcium phosphate dihydrate (DCPD-brushite) hydraulic cements, an apatite hydraulic fiber loaded cement, and a calcium sulfate cement (Plaster of Paris) were implanted in epiphyseal and metaphyseal cylindrical bone defects in sheep. The in vivo study was performed to assess the biocompatibility and bone remodeling of four cement formulations. After time periods of 2, 4, and 6 months, the cement samples were clinically and histologically evaluated. Histomorphometrically, the amount of new bone formation, fibrous tissue, and bone marrow and the area of remaining cement were measured. In all specimens, no signs of inflammation were detectable either macroscopically or microscopically. Cements differed mainly in their resorption time. Calcium sulfate was already completely resorbed at 2 months and showed a variable amount of new bone formation and/or fibrous tissue in the original drill hole over all time periods. The two DCPD cements in contrast were degraded to a large amount at 6 months, whereas the apatite was almost unchanged over all time periods. Copyright © 2013. Published by Elsevier B.V.

Osteoinductive-nanoscaled silk/HA composite scaffolds for bone tissue engineering application.

PubMed

Huang, Xiaowei; Bai, Shumeng; Lu, Qiang; Liu, Xi; Liu, Shanshan; Zhu, Hesun

2015-10-01

Osteoinductive silk/hydroxyapatite (HA) composite scaffolds for bone regeneration were prepared by combining silk with HA/silk core-shell nanoparticles. The HA/silk nanoparticles were directly dispersed in silk solution to form uniform silk/HA blend and then composite scaffolds after a freeze-drying process. The HA/silk nanoparticles uniformly distributed in silk scaffolds at nanometer scale at varying HA content up to 40%, and substantially improved the compressive strength of the scaffolds produced. Rat bone mesenchymal stem cells (rBMSCs) were cultured in these scaffolds and cell proliferation was analyzed by confocal microscopy and DNA assay. Gene expression and biochemical assays were employed to study the influence of increasing HA/silk nanoparticles on in vitro osteogenic differentiation of rBMSCs. Increasing HA/silk nanoparticles inside silk scaffolds improved the growth and osteogenic capability of rBMSCs in the absence of osteogenic growth factors, and also significantly increased the calcium and collagen I deposition. In addition, compared to silk/HA composite scaffolds containing HA aggregates, the scaffolds loaded with HA/silk nanoparticles showed remarkably higher stiffness and better osteogenic property at same HA content, implying a preferable microenvironment for rBMSCs. These results suggest that the osteogenic property as well as mechanical property of silk/HA scaffolds could be further improved through fabricating their structure and topography at nanometer scale, providing more suitable systems for bone regeneration. © 2014 Wiley Periodicals, Inc.

Peri-implant stress correlates with bone and cement morphology: Micro-FE modeling of implanted cadaveric glenoids.

PubMed

Wee, Hwabok; Armstrong, April D; Flint, Wesley W; Kunselman, Allen R; Lewis, Gregory S

2015-11-01

Aseptic loosening of cemented joint replacements is a complex biological and mechanical process, and remains a clinical concern especially in patients with poor bone quality. Utilizing high resolution finite element analysis of a series of implanted cadaver glenoids, the objective of this study was to quantify relationships between construct morphology and resulting mechanical stresses in cement and trabeculae. Eight glenoid cadavers were implanted with a cemented central peg implant. Specimens were imaged by micro-CT, and subject-specific finite element models were developed. Bone volume fraction, glenoid width, implant-cortex distance, cement volume, cement-cortex contact, and cement-bone interface area were measured. Axial loading was applied to the implant of each model and stress distributions were characterized. Correlation analysis was completed across all specimens for pairs of morphological and mechanical variables. The amount of trabecular bone with high stress was strongly negatively correlated with both cement volume and contact between the cement and cortex (r = -0.85 and -0.84, p < 0.05). Bone with high stress was also correlated with both glenoid width and implant-cortex distance. Contact between the cement and underlying cortex may dramatically reduce trabecular bone stresses surrounding the cement, and this contact depends on bone shape, cement amount, and implant positioning. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

Enhanced osteointegration of poly(methylmethacrylate) bone cements by incorporating strontium-containing borate bioactive glass

PubMed Central

Huang, Chengcheng; Zhang, Meng; Ruan, Changshun; Peng, Songlin; Li, Li; Liu, Wenlong; Wang, Ting; Li, Bing; Huang, Wenhai; Rahaman, Mohamed N.; Lu, William W.; Pan, Haobo

2017-01-01

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. PMID:28615491

Enhanced osteointegration of poly(methylmethacrylate) bone cements by incorporating strontium-containing borate bioactive glass.

PubMed

Cui, Xu; Huang, Chengcheng; Zhang, Meng; Ruan, Changshun; Peng, Songlin; Li, Li; Liu, Wenlong; Wang, Ting; Li, Bing; Huang, Wenhai; Rahaman, Mohamed N; Lu, William W; Pan, Haobo

2017-06-01

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. © 2017 The Author(s).

Alumina as a filler for bone cement: a feasibility study.

PubMed

Ackley, M A; Monroe, E

1980-10-01

A composite bone cement of Alcoa A-10 Alumina and very finely ground poly(methyl methacrylate) beads (PMMA) was fabricated. It was tested in an attempt to improve on the conventionally used pure PMMA bone cement. By knowing the densities of the powders and their volumes, the mass of each was calculated for the most efficient packing of PMMA and Al2O3 powders and a 65% PMMA: 35% Al2O3 ratio by weight composition was determined. This was tested, as well as the pure cement so comparisons could be made. Cylinders for the strength tests were also made of silane treated Al2O3. The compositions were tested for compressive and tensile strengths. The pure PMMA, composite and silane treated composite had compressive strengths of 79.64 +/- 13.0, 83.17 +/- 4.8, and 71.52 +/- 8.6 MPa and the tensile strengths were 6.69 +/- 0.6, 5.12 +/- 0.3, and 7.12 +/- 0.5 MPa respectively. Also the 65%-35% PMMA-Al2O3 composite required 64% less monomer for mixing than did the pure cement which is thought to be better for tissue healing. The maximum temperature attained from room temperature was 110 degrees-115 degrees C for both cements. The composite took 6.5 min longer to reach its peak temperature than did the pure cement. The bone cements were implanted for one week in a rabbit and both compositions seemed acceptable by the tissue.

Novel Injectable Calcium Phosphate Bone Cement from Wet Chemical Precipitation Method

NASA Astrophysics Data System (ADS)

Hablee, S.; Sopyan, I.; Mel, M.; Salleh, H. M.; Rahman, M. M.; Singh, R.

2017-06-01

Calcium phosphate cement has been prepared via chemical precipitation method for injectable bone filling materials. Calcium hydroxide, Ca(OH)2, and diammonium hydrogen phosphate, (NH4)2HPO4, were used as calcium and phosphorus precursors respectively. The synthesized powder was mixed with water at different powder-to-liquid (P/L) ratios, which was adjusted at 0.8, 0.9, 1.0, 1.1 and 1.2. The influence of P/L ratio on the injectability, setting time and mechanical strength of calcium phosphate cement paste has been evaluated. The synthesized powder appeared as purely hydroxyapatite with nanosized and agglomerated spherical particles. All cement pastes show excellent injectability except for the paste with P/L ratio 1.2. Calcium phosphate cement with P/L ratio 1.1 shows the ideal cement for bone filler application with good injectability, the initial and final setting times of 30 min and 160 min, and the compression strength of 2.47 MPa. The result indicated that the newly developed calcium phosphate cement is physically suitable for bone filler application. This paper presents our investigation on the effect of P/L ratio on the handling and mechanical properties of calcium phosphate cement prepared via wet chemical precipitation method.

Laminated electrospun nHA/PHB-composite scaffolds mimicking bone extracellular matrix for bone tissue engineering.

PubMed

Chen, Zhuoyue; Song, Yue; Zhang, Jing; Liu, Wei; Cui, Jihong; Li, Hongmin; Chen, Fulin

2017-03-01

Electrospinning is an effective means to generate nano- to micro-scale polymer fibers resembling native extracellular matrix for tissue engineering. However, a major problem of electrospun materials is that limited pore size and porosity may prevent adequate cellular infiltration and tissue ingrowth. In this study, we first prepared thin layers of hydroxyapatite nanoparticle (nHA)/poly-hydroxybutyrate (PHB) via electrospinning. We then laminated the nHA/PHB thin layers to obtain a scaffold for cell seeding and bone tissue engineering. The results demonstrated that the laminated scaffold possessed optimized cell-loading capacity. Bone marrow mesenchymal stem cells (MSCs) exhibited better adherence, proliferation and osteogenic phenotypes on nHA/PHB scaffolds than on PHB scaffolds. Thereafter, we seeded MSCs onto nHA/PHB scaffolds to fabricate bone grafts. Histological observation showed osteoid tissue formation throughout the scaffold, with most of the scaffold absorbed in the specimens 2months after implantation, and blood vessels ingrowth into the graft could be observed in the graft. We concluded that electrospun and laminated nanoscaled biocomposite scaffolds hold great therapeutic potential for bone regeneration. Copyright © 2016 Elsevier B.V. All rights reserved.

The long-term in vivo behavior of polymethyl methacrylate bone cement in total hip arthroplasty.

PubMed

Oonishi, Hiroyuki; Akiyama, Haruhiko; Takemoto, Mitsuru; Kawai, Toshiyuki; Yamamoto, Koji; Yamamuro, Takao; Oonishi, Hironobu; Nakamura, Takashi

2011-10-01

The long-term success of cemented total hip arthroplasty (THA) has been well established. Improved outcomes, both radiographically and clinically, have resulted mainly from advances in stem design and improvements in operating techniques. However, there is concern about the durability of bone cement in vivo. We evaluated the physical and chemical properties of CMW1 bone cements retrieved from patients undergoing revision THA. CMW1 cements were retrieved from 14 patients who underwent acetabular revision because of aseptic loosening. The time in vivo before revision was 7-30 years. The bending properties of the retrieved bone cement were assessed using the three-point bending method. The molecular weight and chemical structure were analyzed by gel permeation chromatography and Fourier-transform infrared spectroscopy. The porosity of the bone cements was evaluated by 3-D microcomputer tomography. The bending strength decreased with increasing time in vivo and depended on the density of the bone cement, which we assume to be determined by the porosity. There was no correlation between molecular weight and time in vivo. The infrared spectra were similar in the retrieved cements and in the control CMW1 cements. Our results indicate that polymer chain scission and significant hydrolysis do not occur in CMW1 cement after implantation in vivo, even in the long term. CMW1 cement was stable through long-term implantation and functional loading.

The long-term in vivo behavior of polymethyl methacrylate bone cement in total hip arthroplasty

PubMed Central

2011-01-01

Background and purpose The long-term success of cemented total hip arthroplasty (THA) has been well established. Improved outcomes, both radiographically and clinically, have resulted mainly from advances in stem design and improvements in operating techniques. However, there is concern about the durability of bone cement in vivo. We evaluated the physical and chemical properties of CMW1 bone cements retrieved from patients undergoing revision THA. Methods CMW1 cements were retrieved from 14 patients who underwent acetabular revision because of aseptic loosening. The time in vivo before revision was 7–30 years. The bending properties of the retrieved bone cement were assessed using the three-point bending method. The molecular weight and chemical structure were analyzed by gel permeation chromatography and Fourier-transform infrared spectroscopy. The porosity of the bone cements was evaluated by 3-D microcomputer tomography. Results The bending strength decreased with increasing time in vivo and depended on the density of the bone cement, which we assume to be determined by the porosity. There was no correlation between molecular weight and time in vivo. The infrared spectra were similar in the retrieved cements and in the control CMW1 cements. Interpretation Our results indicate that polymer chain scission and significant hydrolysis do not occur in CMW1 cement after implantation in vivo, even in the long term. CMW1 cement was stable through long-term implantation and functional loading. PMID:22103279

Synthesization and characterization of poly(lactic-co-glycolic acid) / calcium phosphate bone cement from crab shells

NASA Astrophysics Data System (ADS)

Hanan, M. R. Abdul; Daud, N. M.; Ismail, L. H.; Saidin, S.

2017-05-01

An injectable calcium phosphate (CaP) bone cement has been widely used for musculoskeletal and bone disorder due to its biocompatible and osteoconductive properties. In this study, CaP was successfully synthesized from crab shells by a wet chemical route. Poly(lactic-co-glycolic acid) (PLGA) microspheres which have been produced through a double emulsion technique were incorporated into the CaP mixture for the purpose of bone cement solidification. The ratio of both compounds, CaP and PLGA, were set at 8:2. The CaP and PLGA/CaP bone cement were analyzed by ATR-FTIR, FESEM-EDX and contact angle analyses. The bone cement was composed of CaP and PLGA where the micro-powders of CaP were agglomerated on the PLGA microspheres. Addition of the PLGA has increased the hydrophilicity of the bone cement which will be beneficial for materials degradation and bone integration.

Evaluation of the effects of implant materials and designs on thermal necrosis of bone in cemented hip arthroplasty.

PubMed

Li, Chaodi; Kotha, Shiva; Mason, James

2003-01-01

The exothermic polymerization of bone cement may induce thermal necrosis of bone in cemented hip arthroplasty. A finite element formulation was developed to predict the evolution of the temperature with time in the cemented hip replacement system. The developed method is capable of taking into account both the chemical reaction that generates heat during bone cement polymerization (through a kinetic model) and the physical process of heat conduction (with an energy balance equation). The possibility of thermal necrosis of bone was then evaluated based on the temperature history in the bone and an appropriate damage criterion. Specifically, we evaluate the role of implant materials and designs on the thermal response of the system. Results indicated that the peak temperature at the bone/cement interface with a metal prosthesis was lower than that with a polymer or a composite prosthesis in hip replacement systems. Necrosis of bone was predicted to occur with a polymer or a composite prosthesis while no necrosis was predicted with a metal prosthesis in the simulated conditions. When reinforcing osteoporotic hips with injected bone cement in the cancellous core of the femur, the volume of bone cement implanted is increased which may increase the risk of thermal necrosis of bone. We evaluate whether this risk can be decreased through the use of an insulator to contain the bone cement. No thermal necrosis of bone was predicted with a 3 mm thick polyurethane insulator while more damage is predicted for the use of bone cement without the insulator. This method provides a numerical tool for the quantitative simulation of the thermal behavior of bone-cement-prosthesis designs and for examining and refining new designs computationally.

Does PEEK/HA Enhance Bone Formation Compared With PEEK in a Sheep Cervical Fusion Model?

PubMed

Walsh, William R; Pelletier, Matthew H; Bertollo, Nicky; Christou, Chris; Tan, Chris

2016-11-01

Polyetheretherketone (PEEK) has a wide range of clinical applications but does not directly bond to bone. Bulk incorporation of osteoconductive materials including hydroxyapatite (HA) into the PEEK matrix is a potential solution to address the formation of a fibrous tissue layer between PEEK and bone and has not been tested. Using in vivo ovine animal models, we asked: (1) Does PEEK-HA improve cortical and cancellous bone ongrowth compared with PEEK? (2) Does PEEK-HA improve bone ongrowth and fusion outcome in a more challenging functional ovine cervical fusion model? The in vivo responses of PEEK-HA Enhanced and PEEK-OPTIMA ® Natural were evaluated for bone ongrowth in the form of dowels implanted in the cancellous and cortical bone of adult sheep and examined at 4 and 12 weeks as well as interbody cervical fusion at 6, 12, and 26 weeks. The bone-implant interface was evaluated with radiographic and histologic endpoints for a qualitative assessment of direct bone contact of an intervening fibrous tissue later. Gamma-irradiated cortical allograft cages were evaluated as well. Incorporating HA into the PEEK matrix resulted in more direct bone apposition as opposed to the fibrous tissue interface with PEEK alone in the bone ongrowth as well as interbody cervical fusions. No adverse reactions were found at the implant-bone interface for either material. Radiography and histology revealed resorption and fracture of the allograft devices in vivo. Incorporating HA into PEEK provides a more favorable environment than PEEK alone for bone ongrowth. Cervical fusion was improved with PEEK-HA compared with PEEK alone as well as allograft bone interbody devices. Improving the bone-implant interface with a PEEK device by incorporating HA may improve interbody fusion results and requires further clinical studies.

Bone Regeneration Using a Mixture of Silicon-Substituted Coral HA and β-TCP in a Rat Calvarial Bone Defect Model

PubMed Central

Roh, Jiyeon; Kim, Ji-Youn; Choi, Young-Muk; Ha, Seong-Min; Kim, Kyoung-Nam; Kim, Kwang-Mahn

2016-01-01

The demand of bone graft materials has been increasing. Among various origins of bone graft materials, natural coral composed of up to 99% calcium carbonate was chosen and converted into hydroxyapatite (HA); silicon was then substituted into the HA. Then, the Si-HA was mixed with β-tricalcium phosphate (TCP) in the ratios 100:0 (S100T0), 70:30 (S70T30), 60:40 (S60T40), and 50:50 (S50T50). The materials were implanted for four and eight weeks in a rat calvarial bone defect model (8 mm). The MBCPTM (HA:β-TCP = 60:40, Biomatalante, Vigneux de Bretagne, France) was used as a control. After euthanasia, the bone tissue was analyzed by making histological slides. From the results, S60T40 showed the fastest bone regeneration in four weeks (p < 0.05). In addition, S60T40, S50T50, and MBCPTM showed significant new bone formation in eight weeks (p < 0.05). In conclusion, Si-HA/TCP showed potential as a bone graft material. PMID:28787903

Bone Regeneration Using a Mixture of Silicon-Substituted Coral HA and β-TCP in a Rat Calvarial Bone Defect Model.

PubMed

Roh, Jiyeon; Kim, Ji-Youn; Choi, Young-Muk; Ha, Seong-Min; Kim, Kyoung-Nam; Kim, Kwang-Mahn

2016-02-06

The demand of bone graft materials has been increasing. Among various origins of bone graft materials, natural coral composed of up to 99% calcium carbonate was chosen and converted into hydroxyapatite (HA); silicon was then substituted into the HA. Then, the Si-HA was mixed with β-tricalcium phosphate (TCP) in the ratios 100:0 (S100T0), 70:30 (S70T30), 60:40 (S60T40), and 50:50 (S50T50). The materials were implanted for four and eight weeks in a rat calvarial bone defect model (8 mm). The MBCPTM (HA:β-TCP = 60:40, Biomatalante, Vigneux de Bretagne, France) was used as a control. After euthanasia, the bone tissue was analyzed by making histological slides. From the results, S60T40 showed the fastest bone regeneration in four weeks (p < 0.05). In addition, S60T40, S50T50, and MBCPTM showed significant new bone formation in eight weeks (p < 0.05). In conclusion, Si-HA/TCP showed potential as a bone graft material.

3D-Printed Bioactive Ca3SiO5 Bone Cement Scaffolds with Nano Surface Structure for Bone Regeneration.

PubMed

Yang, Chen; Wang, Xiaoya; Ma, Bing; Zhu, Haibo; Huan, Zhiguang; Ma, Nan; Wu, Chengtie; Chang, Jiang

2017-02-22

Silicate bioactive materials have been widely studied for bone regeneration because of their eminent physicochemical properties and outstanding osteogenic bioactivity, and different methods have been developed to prepare porous silicate bioactive ceramics scaffolds for bone-tissue engineering applications. Among all of these methods, the 3D-printing technique is obviously the most efficient way to control the porous structure. However, 3D-printed bioceramic porous scaffolds need high-temperature sintering, which will cause volume shrinkage and reduce the controllability of the pore structure accuracy. Unlike silicate bioceramic, bioactive silicate cements such as tricalcium silicate (Ca 3 SiO 5 and C 3 S) can be self-set in water to obtain high mechanical strength under mild conditions. Another advantage of using C 3 S to prepare 3D scaffolds is the possibility of simultaneous drug loading. Herein, we, for the first time, demonstrated successful preparation of uniform 3D-printed C 3 S bone cement scaffolds with controllable 3D structure at room temperature. The scaffolds were loaded with two model drugs and showed a loading location controllable drug-release profile. In addition, we developed a surface modification process to create controllable nanotopography on the surface of pore wall of the scaffolds, which showed activity to enhance rat bone-marrow stem cells (rBMSCs) attachment, spreading, and ALP activities. The in vivo experiments revealed that the 3D-printed C 3 S bone cement scaffolds with nanoneedle-structured surfaces significantly improved bone regeneration, as compared to pure C 3 S bone cement scaffolds, suggesting that 3D-printed C 3 S bone cement scaffolds with controllable nanotopography surface are bioactive implantable biomaterials for bone repair.

Investigation of fatigue crack growth in acrylic bone cement using the acoustic emission technique.

PubMed

Roques, A; Browne, M; Thompson, J; Rowland, C; Taylor, A

2004-02-01

Failure of the bone cement mantle has been implicated in the loosening process of cemented hip stems. Current methods of investigating degradation of the cement mantle in vitro often require sectioning of the sample to confirm failure paths. The present research investigates acoustic emission as a passive experimental method for the assessment of bone cement failure. Damage in bone cement was monitored during four point bending fatigue tests through an analysis of the peak amplitude, duration, rise time (RT) and energy of the events emitted from the damage sections. A difference in AE trends was observed during failure for specimens aged and tested in (i) air and (ii) Ringer's solution at 37 degrees C. It was noted that the acoustic behaviour varied according to applied load level; events of higher duration and RT were emitted during fatigue at lower stresses. A good correlation was observed between crack location and source of acoustic emission, and the nature of the acoustic parameters that were most suited to bone cement failure characterisation was identified. The methodology employed in this study could potentially be used as a pre-clinical assessment tool for the integrity of cemented load bearing implants.

Mechanical, material, and antimicrobial properties of acrylic bone cement impregnated with silver nanoparticles.

PubMed

Slane, Josh; Vivanco, Juan; Rose, Warren; Ploeg, Heidi-Lynn; Squire, Matthew

2015-03-01

Prosthetic joint infection is one of the most serious complications that can lead to failure of a total joint replacement. Recently, the rise of multidrug resistant bacteria has substantially reduced the efficacy of antibiotics that are typically incorporated into acrylic bone cement. Silver nanoparticles (AgNPs) are an attractive alternative to traditional antibiotics resulting from their broad-spectrum antimicrobial activity and low bacterial resistance. The purpose of this study, therefore, was to incorporate metallic silver nanoparticles into acrylic bone cement and quantify the effects on the cement's mechanical, material and antimicrobial properties. AgNPs at three loading ratios (0.25, 0.5, and 1.0% wt/wt) were incorporated into a commercial bone cement using a probe sonication technique. The resulting cements demonstrated mechanical and material properties that were not substantially different from the standard cement. Testing against Staphylococcus aureus and Staphylococcus epidermidis using Kirby-Bauer and time-kill assays demonstrated no antimicrobial activity against planktonic bacteria. In contrast, cements modified with AgNPs significantly reduced biofilm formation on the surface of the cement. These results indicate that AgNP-loaded cement is of high potential for use in primary arthroplasty where prevention of bacterial surface colonization is vital. Copyright © 2014 Elsevier B.V. All rights reserved.

Cements of doped calcium phosphates for bone implantation =

NASA Astrophysics Data System (ADS)

Pina, Sandra Cristina de Almeida

for trabecular bone (10-30 MPa). Cell cultures used to evaluate citotoxicity, bioactivity and biocompatibility of cements revealed no toxic effects. The biocompatibility in vivo and cements resorption were evaluated using a pig model through histological and histomorphometric studies of decalcified sections. The results show that the implanted cements are biocompatible and osteoconductive, without foreign body reaction. These properties make them good candidates for applications as bone substitutes. None

Variability of the pullout strength of cancellous bone screws with cement augmentation.

PubMed

Procter, P; Bennani, P; Brown, C J; Arnoldi, J; Pioletti, D P; Larsson, S

2015-06-01

Orthopaedic surgeons often face clinical situations where improved screw holding power in cancellous bone is needed. Injectable calcium phosphate cements are one option to enhance fixation. Paired screw pullout tests were undertaken in which human cadaver bone was augmented with calcium phosphate cement. A finite element model was used to investigate sensitivity to screw positional placement. Statistical analysis of the data concluded that the pullout strength was generally increased by cement augmentation in the in vitro human cadaver tests. However, when comparing the individual paired samples there were surprising results with lower strength than anticipated after augmentation, in apparent contradiction to the generally expected conclusion. Investigation using the finite element model showed that these strength reductions could be accounted for by small screw positional changes. A change of 0.5mm might result in predicted pullout force changes of up to 28%. Small changes in screw position might lead to significant changes in pullout strength sufficient to explain the lower than expected individual pullout values in augmented cancellous bone. Consequently whilst the addition of cement at a position of low strength would increase the pullout strength at that point, it might not reach the pullout strength of the un-augmented paired test site. However, the overall effect of cement augmentation produces a significant improvement at whatever point in the bone the screw is placed. The use of polymeric bone-substitute materials for tests may not reveal the natural variation encountered in tests using real bone structures. Copyright © 2015 Elsevier Ltd. All rights reserved.

PCL-HA microscaffolds for in vitro modular bone tissue engineering.

PubMed

Totaro, Alessandra; Salerno, Aurelio; Imparato, Giorgia; Domingo, Concepción; Urciuolo, Francesco; Netti, Paolo Antonio

2017-06-01

The evolution of microscaffolds and bone-bioactive surfaces is a pivotal point in modular bone tissue engineering. In this study, the design and fabrication of porous polycaprolactone (PCL) microscaffolds functionalized with hydroxyapatite (HA) nanoparticles by means of a bio-safe and versatile thermally-induced phase separation process is reported. The ability of the as-prepared nanocomposite microscaffolds to support the adhesion, growth and osteogenic differentiation of human mesenchymal stem cells (hMSCs) in standard and osteogenic media and using dynamic seeding/culture conditions was investigated. The obtained results demonstrated that the PCL-HA nanocomposite microparticles had an enhanced interaction with hMSCs and induced their osteogenic differentiation, even without the exogenous addition of osteogenic factors. In particular, calcium deposition, alizarin red assay, histological analysis, osteogenic gene expression and collagen I secretion were assessed. The results of these tests demonstrated the formation of bone microtissue precursors after 28 days of dynamic culture. These findings suggest that PCL-HA nanocomposite microparticles represent an excellent platform for in vitro modular bone tissue engineering. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

Cement line staining in undecalcified thin sections of cortical bone

NASA Technical Reports Server (NTRS)

Bain, S. D.; Impeduglia, T. M.; Rubin, C. T.

1990-01-01

A technique for demonstrating cement lines in thin, undecalcified, transverse sections of cortical bone has been developed. Cortical bone samples are processed and embedded undecalcified in methyl methacrylate plastic. After sectioning at 3-5 microns, cross-sections are transferred to a glass slide and flattened for 10 min. Sections of cortical bone are stained for 20 sec free-floating in a fresh solution of 1% toluidine blue dissolved in 0.1% formic acid. The section is dehydrated in t-butyl alcohol, cleared in xylene, and mounted with Eukitt's medium. Reversal lines appear as thin, scalloped, dark blue lines against a light blue matrix, whereas bone formation arrest lines are thicker with a smooth contour. With this technique cellular detail, osteoid differentiation, and fluorochrome labels are retained. Results demonstrate the applicability of a one-step staining method for cement lines which will facilitate the assessment of bone remodeling activity in thin sections of undecalcified cortical bone.

Liquid-solid phase transition alloy as reversible and rapid molding bone cement.

PubMed

Yi, Liting; Jin, Chao; Wang, Lei; Liu, Jing

2014-12-01

Acrylic bone cement has been an essential non-metallic implant used as fixing agent in the cemented total joint arthroplasty (THA). However, the currently available materials based mainly on polymethylmethacrylate (PMMA) still encounter certain limitations, such as time-consuming polymerization, thermal and chemical necrosis and troublesome revision procedure. Here from an alternative way, we proposed for the first time to adopt the injectable alloy cement to address such tough issues through introducing its unique liquid-solid phase transition mechanism. A typical cement along this way is thus made of an alloy Bi/In/Sn/Zn with a specifically designed low melting point 57.5 °C, which enables its rapid molding into various desired shapes with high plasticity and ultimate metallic behaviors. The fundamental characteristics including the mechanical strength, biocompatibility and phase transition-induced thermal effects have been clarified to demonstrate the importance of such alloy as unconventional cement with favorable merits. In addition, we also disclosed its advantage as an excellent contrast agent for radiation imaging on the bone interior structure which is highly beneficial for guiding the surgery and monitoring the therapeutic effects. Particularly, the proposed alloy cement with reversible phase transition feature significantly simplifies the revision of the cement and prosthesis. This study opens the way for employing the injectable alloy materials as reversible bone cement to fulfill diverse clinical needs in the coming time. Copyright © 2014 Elsevier Ltd. All rights reserved.

Osteoconductive Amine-Functionalized Graphene-Poly(methyl methacrylate) Bone Cement Composite with Controlled Exothermic Polymerization.

PubMed

Sharma, Rakesh; Kapusetti, Govinda; Bhong, Sayali Yashwant; Roy, Partha; Singh, Santosh Kumar; Singh, Shikha; Balavigneswaran, Chelladurai Karthikeyan; Mahato, Kaushal Kumar; Ray, Biswajit; Maiti, Pralay; Misra, Nira

2017-09-20

Bone cement has found extensive usage in joint arthroplasty over the last 50 years; still, the development of bone cement with essential properties such as high fatigue resistance, lower exothermic temperature, and bioactivity has been an unsolved problem. In our present work, we have addressed all of the mentioned shortcomings of bone cement by reinforcing it with graphene (GR), graphene oxide (GO), and surface-modified amino graphene (AG) fillers. These nanocomposites have shown hypsochromic shifts, suggesting strong interactions between the filler material and the polymer matrix. AG-based nanohybrids have shown greater osteointegration and lower cytotoxicity compared to other nanohybrids as well as pristine bone cement. They have also reduced oxidative stress on cells, resulting in calcification within 20 days of the implantation of nanohybrids into the rabbits. They have significantly reduced the exothermic curing temperature to body temperature and increased the setting time to facilitate practitioners, suggesting that reaction temperature and settling time can be dynamically controlled by varying the concentration of the filler. Thermal stability and enhanced mechanical properties have been achieved in nanohybrids vis-à-vis pure bone cement. Thus, this newly developed nanocomposite can create natural bonding with bone tissues for improved bioactivity, longer sustainability, and better strength in the prosthesis.

A novel liposomal drug delivery system for PMMA bone cements

PubMed Central

Birchall, James C.; Evans, Samuel L.; Denyer, Stephen P.

2015-01-01

Abstract The population in developed countries is ageing and the number of people experiencing joint‐related conditions, such as osteoarthritis, is expected to increase. Joint replacements are currently the most effective treatment for severe joint conditions and although many of these procedures are successful, infection developing after the procedure is still an issue, requiring complex and expensive revisions. Whilst incorporating a powdered antibiotic within the bone cement can reduce infection rates, the powder frequently agglomerates, resulting in poor antibiotic release characteristics and compromised mechanical performance of the cement. To overcome these issues, a novel delivery system consisting of antibiotic‐loaded nano‐sized liposomes was developed for inclusion into polymethyl methacrylate (PMMA) bone cement. This system was tested in a commercial cement (Palacos R) and consistently delivered a higher percentage (22%) of the incorporated antibiotic when compared to the powdered antibiotic cement (9%), meaning less antibiotic needs to be incorporated than with conventional cement. The novel system resulted in a controlled and gradual release of antibiotic over a longer, 30‐day period and enhanced the toughness, bending strength and Vickers hardness of the cement, without altering its polymerization or molecular structure. This new material has the potential to significantly reduce infections in cemented joint replacements leading to enhanced patient quality of life and reduced healthcare costs. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 1510–1524, 2016. PMID:26256271

Ageing and moisture uptake in polymethyl methacrylate (PMMA) bone cements.

PubMed

Ayre, Wayne Nishio; Denyer, Stephen P; Evans, Samuel L

2014-04-01

Bone cements are extensively employed in orthopaedics for joint arthroplasty, however implant failure in the form of aseptic loosening is known to occur after long-term use. The exact mechanism causing this is not well understood, however it is thought to arise from a combination of fatigue and chemical degradation resulting from the hostile in vivo environment. In this study, two commercial bone cements were aged in an isotonic fluid at physiological temperatures and changes in moisture uptake, microstructure and mechanical and fatigue properties were studied. Initial penetration of water into the cement followed Fickian diffusion and was thought to be caused by vacancies created by leaching monomer. An increase in weight of approximately 2% was experienced after 30 days ageing and was accompanied by hydrolysis of poly(methyl methacrylate) (PMMA) in the outermost layers of the cement. This molecular change and the plasticising effect of water resulted in reduced mechanical and fatigue properties over time. Cement ageing is therefore thought to be a key contributor in the long-term failure of cemented joint replacements. The results from this study have highlighted the need to develop cements capable of withstanding long-term degradation and for more accurate test methods, which fully account for physiological ageing. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

Influence of lactose addition to gentamicin-loaded acrylic bone cement on the kinetics of release of the antibiotic and the cement properties.

PubMed

Frutos, Gloria; Pastor, José Ygnacio; Martínez, Noelia; Virto, María Rosa; Torrado, Susana

2010-03-01

The purpose of this study was to characterize a poly(methyl methacrylate) bone cement that was loaded with the antibiotic gentamicin sulphate (GS) and lactose, which served to modulate the release of GS from cement specimens. The release of GS when the cement specimens were immersed in phosphate-buffered saline at 37 degrees Celsius was determined spectrophotometrically. The microstructure, porosity, density, tensile properties and flexural properties of the cements were determined before and after release of GS. A kinetics model of the release of GS from the cement that involved a coupled mechanism based on dissolution/diffusion processes and an initial burst effect was proposed. Dissolution assay results showed that drug elution was controlled by a diffusion mechanism which can be modulated by lactose addition. Density values and mechanical properties (tensile strength, flexural strength, elastic modulus and fracture toughness) were reduced by the increased porosity resulting from lactose addition, but maintained acceptable values for the structural functions of bone cement. The present results suggest that lactose-modified, gentamicin-loaded acrylic bone cements are potential candidates for use in various orthopaedic and dental applications. Copyright 2009 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

[Effect of different bone cement dispersion types in the treatment of osteoporotic vertebral compression fracture].

PubMed

Zhao, Yong-Sheng; Li, Qiang; Li, Qiang; Zheng, Yan-Ping

2017-05-25

To observe different bone cement dispersion types of PVP, PKP and manipulative reduction PVP and their effects in the treatment of senile osteoporotic vertebral compression fractures and the bone cement leakage rate. The clinical data of patients with osteoporotic vertebral compression fractures who underwent unilateral vertebroplasty from January 2012 to January 2015 was retrospectively analyzed. Of them, 56 cases including 22 males and 34 females aged from 60 to 78 years old were treated by PVP operation; Fouty-eight cases including 17 males and 31 females aged from 61 to 79 years old were treated by PKP operation; Forty-three cases including 15 males and 28 females aged from 60 to 76 years old were treated by manipulative reduction PVP operation. AP and lateral DR films were taken after the operation; the vertebral bone cement diffusion district area and mass district area were calculated with AutoCAD graphics processing software by AP and lateral DR picture, then ratio(K) of average diffusion area and mass area were calculated, defining K<50% as mass type, 50%<=K<=100% as mixed type and K>100% as diffusion type. Different bone cement dispersion types of PVP, PKP and manipulative reduction PVP operation were analyzed. According to bone cement dispersion types, patients were divided into diffusion type, mixed type and mass type groups.Visual analogue scale (VAS), vertebral body compression rate, JOA score and bone cement leakage rate were observed. All patients were followed up for 12-24 months with an average of 17.2 months. There was significant difference in bone cement dispersion type among three groups ( P <0.05). The constituent ratio of diffusion type, mixed type and mass type in PVP operation was 46.43%, 35.71%, 17.86%, in PKP was 16.67%, 37.50% , 45.83%, and in manipulative reduction PVP was 37.21%, 44.19% and 18.60%, respectively. PVP operation and manipulative reduction PVP were mainly composed of diffusion type and mixed type, while PKP was mainly

Experimental ex-vivo validation of PMMA-based bone cements loaded with magnetic nanoparticles enabling hyperthermia of metastatic bone tumors

NASA Astrophysics Data System (ADS)

Harabech, Mariem; Kiselovs, Normunds Rungevics; Maenhoudt, Wim; Crevecoeur, Guillaume; Van Roost, Dirk; Dupré, Luc

2017-05-01

Percutaneous vertebroplasty comprises the injection of Polymethylmethacrylate (PMMA) bone cement into vertebrae and can be used for the treatment of compression fractures of vertebrae. Metastatic bone tumors can cause such compression fractures but are not treated when injecting PMMA-based bone cement. Hyperthermia of tumors can on the other hand be attained by placing magnetic nanoparticles (MNPs) in an alternating magnetic field (AMF). Loading the PMMA-based bone cement with MNPs could both serve vertebra stabilization and metastatic bone tumor hyperthermia when subjecting this PMMA-MNP to an AMF. A dedicated pancake coil is designed with a self-inductance of 10 μH in series with a capacitance of 0.1 μF that acts as resonant inductor-capacitor circuit to generate the AMF. The thermal rise is appraised in beef vertebra placed at 10 cm from the AMF generating circuit using optical temperatures sensors, i.e. in the center of the PMMA-MNP bone cement, which is located in the vicinity of metastatic bone tumors in clinical applications; and in the spine, which needs to be safeguarded to high temperature exposures. Results show a temperature rise of about 7 °C in PMMA-MNP whereas the temperature rise in the spine remains limited to 1 °C. Moreover, multicycles heating of PMMA-MNP is experimentally verified, validating the technical feasibility of having PMMA-MNP as basic component for percutaneous vertebroplasty combined with hyperthermia treatment of metastatic bone tumors.

Electrocoagulation improving bone cement use in middle-ear surgery: short-term and middle-term results.

PubMed

Galy-Bernadoy, C; Akkari, M; Mondain, M; Uziel, A; Venail, F

2016-12-01

Bone cement is used for ossicular chain repair and revision stapes surgery. Its efficient use requires cautious removal of mucosa from the ossicles. This paper reports a technique for easy, fast and safe removal of this mucosa prior to cement application. It consists of the application of monopolar electrocoagulation on the ossicles prior to bone cement application. The outcomes of six cases of revision stapes surgery and seven cases of partial ossiculoplasty, conducted between 2007 and 2012 using this new technique, were evaluated. Intra-operative reports and audiometric data were collected. During the last assessment, reconstruction using bone cement resulted in mean post-operative air-bone gaps of 4.1 ± 6.5 dB in revision stapes surgery cases and 5.7 ± 5.5 dB in partial ossiculoplasty cases, reflecting a significant hearing improvement (p = 0.03). No complications were observed. Electrocoagulation allows the removal of mucosa from the ossicles in an easy, fast and safe manner, enabling the use of bone cement for ossicular chain reconstruction.

Hypothermic manipulation of bone cement can extend the handling time during vertebroplasty.

PubMed

Lai, Po-Liang; Tai, Ching-Lung; Chu, I-Ming; Fu, Tsai-Sheng; Chen, Lih-Huei; Chen, Wen-Jer

2012-10-16

Polymethylmethacrylate (PMMA) is commonly used for clinical applications. However, the short handling time increases the probability of a surgeon missing the crucial period in which the cement maintains its ideal viscosity for a successful injection. The aim of this article was to illustrate the effects a reduction in temperature would have on the cement handling time during percutaneous vertebroplasty. The injectability of bone cement was assessed using a cement compressor. By twisting the compressor, the piston transmits its axial load to the plunger, which then pumps the bone cement out. The experiments were categorized based on the different types of hypothermic manipulation that were used. In group I (room temperature, sham group), the syringes were kept at 22°C after mixing the bone cement. In group 2 (precooling the bone cement and the container), the PMMA powder and liquid, as well as the beaker, spatula, and syringe, were stored in the refrigerator (4°C) overnight before mixing. In group 3 (ice bath cooling), the syringes were immediately submerged in ice water after mixing the bone cement at room temperature. The average liquid time, paste time, and handling time were 5.1 ± 0.7, 3.4 ± 0.3, and 8.5 ± 0.8 min, respectively, for group 1; 9.4 ± 1.1, 5.8 ± 0.5, and 15.2 ± 1.2 min, respectively, for group 2; and 83.8 ± 5.2, 28.8 ± 6.9, and 112.5 ± 11.3 min, respectively, for group 3. The liquid and paste times could be increased through different cooling methods. In addition, the liquid time (i.e. waiting time) for ice bath cooling was longer than for that of the precooling method (p < 0.05). Both precooling (i.e. lowering the initial temperature) and ice bath cooling (i.e. lowering the surrounding temperature) can effectively slow polymerization. Precooling is easy for clinical applications, while ice bath cooling might be more suitable for multiple-level vertebroplasty. Clinicians can take advantage of the improved injectability without any

Hypothermic manipulation of bone cement can extend the handling time during vertebroplasty

PubMed Central

2012-01-01

Background Polymethylmethacrylate (PMMA) is commonly used for clinical applications. However, the short handling time increases the probability of a surgeon missing the crucial period in which the cement maintains its ideal viscosity for a successful injection. The aim of this article was to illustrate the effects a reduction in temperature would have on the cement handling time during percutaneous vertebroplasty. Methods The injectability of bone cement was assessed using a cement compressor. By twisting the compressor, the piston transmits its axial load to the plunger, which then pumps the bone cement out. The experiments were categorized based on the different types of hypothermic manipulation that were used. In group I (room temperature, sham group), the syringes were kept at 22°C after mixing the bone cement. In group 2 (precooling the bone cement and the container), the PMMA powder and liquid, as well as the beaker, spatula, and syringe, were stored in the refrigerator (4°C) overnight before mixing. In group 3 (ice bath cooling), the syringes were immediately submerged in ice water after mixing the bone cement at room temperature. Results The average liquid time, paste time, and handling time were 5.1 ± 0.7, 3.4 ± 0.3, and 8.5 ± 0.8 min, respectively, for group 1; 9.4 ± 1.1, 5.8 ± 0.5, and 15.2 ± 1.2 min, respectively, for group 2; and 83.8 ± 5.2, 28.8 ± 6.9, and 112.5 ± 11.3 min, respectively, for group 3. The liquid and paste times could be increased through different cooling methods. In addition, the liquid time (i.e. waiting time) for ice bath cooling was longer than for that of the precooling method (p < 0.05). Conclusions Both precooling (i.e. lowering the initial temperature) and ice bath cooling (i.e. lowering the surrounding temperature) can effectively slow polymerization. Precooling is easy for clinical applications, while ice bath cooling might be more suitable for multiple-level vertebroplasty. Clinicians can take advantage of the

Effects of self-blood on the molding process of polymethyl methacrylate bone cement.

PubMed

Guo, Ying-Jun; Nie, Lin; Zhang, Wen; Mu, Qing

2014-01-01

To evaluate whether the self-blood has influence on the molding process of polymethyl methacrylate (PMMA) bone cement, and to make sure whether it is valuable for the clinical practice. An in vitro study was performed to evaluate the prolonging-effect of self-blood on PMMA bone cement. The effect of prolonging was evaluated by the dough time (TD) and operable time (TO). Moreover, hardness test, squeezing value test and peak temperature test were also conducted to complete the evaluation of this program. The self-blood, especially the plasma, could greatly prolong the handling time of PMMA bone cement without affecting its basic characteristics including hardness, leakage level and peak temperature. On the other hand, we found that in some abnormal conditions, for example with hyperlipemia, self-blood though can also prolong the handling time, would cause some side-effects. We report a new effective way to prolong the handling time of PMMA bone cement by adding moderate amount of self-blood. But "individualized medicine" should be noticed because some abnormal conditions like hyperlipemia would cause undesired side-effects.

The Use of Micro and Nano Particulate Fillers to Modify the Mechanical and Material Properties of Acrylic Bone Cement

NASA Astrophysics Data System (ADS)

Slane, Joshua A.

Acrylic bone cement (polymethyl methacrylate) is widely used in total joint replacements to provide long-term fixation of implants. In essence, bone cement acts as a grout by filling in the voids left between the implant and the patient's bone, forming a mechanical interlock. While bone cement is considered the `gold standard' for implant fixation, issues such as mechanical failure of the cement mantle (aseptic loosening) and the development of prosthetic joint infection (PJI) still plague joint replacement procedures and often necessitate revision arthroplasty. In an effort to address these failures, various modifications are commonly made to bone cement such as mechanical reinforcement with particles/fibers and the addition of antibiotics to mitigate PJI. Despite these attempts, issues such as poor particle interfacial adhesion, inadequate drug release, and the development of multidrug resistant bacteria limit the effectiveness of bone cement modifications. Therefore, the overall goal of this work was to use micro and nanoparticles to enhance the properties of acrylic bone cement, with particular emphasis placed on improving the mechanical properties, cumulative antibiotic release, and antimicrobial properties. An acrylic bone cement (Palacos R) was modified with three types of particles in various loading ratios: mesoporous silica nanoparticles (for mechanical reinforcement), xylitol microparticles (for increased antibiotic release), and silver nanoparticles (as an antimicrobial agent). These particles were used as sole modifications, not in tandem with one another. The resulting cement composites were characterized using a variety of mechanical (macro to nano, fatigue, fracture, and dynamic), imaging, chemical, thermal, biological, and antimicrobial testing techniques. The primary outcomes of this dissertation demonstrate that: (1) mesoporous silica, as used in this work, is a poor reinforcement phase for acrylic bone cement, (2) xylitol can significantly

In-vitro biocompatibility, bioactivity, and mechanical strength of PMMA-PCL polymer containing fluorapatite and graphene oxide bone cements.

PubMed

Pahlevanzadeh, F; Bakhsheshi-Rad, H R; Hamzah, E

2018-06-01

In this study, a bone cement consisting of poly methyl methacrylate (PMMA)-poly caprolactone (PCL)-fluorapatite (FA)-graphene oxide (GO) was synthesized as bone filler for application in orthopedic surgeries. The FA and GO particulates were homogenously distributed in the PMMA-PCL polymer matrix and no defects and agglomeration were found in the PMMA-PCL/FA/GO bone cement. The in-vitro bioactivity result exhibited that addition of FA and GO to the polymer cement (PMMA-PCL) improved the apatite formation ability on the surface of polymer. The results also showed that addition of FA to the polymer bone cement escalated the compressive strength and elastic modulus while reducing elongation to 8 ± 2%. However, after addition of GO into the PMMA-PCL/FA bone cement, both compressive strength and elongation considerably increased to 101 ± 5 MPa and 35 ± 6%, respectively. Furthermore, tensile tests exhibited that inclusion of GO was favorable in improving the tensile modulus, UTS and elongation of the PMMA-PCL/FA bone cement. The cytotoxicity test pointed out that MG63 osteoblast cells viability increased to 279 ± 15% after addition of FA and GO to the PMMA-PCL polymer bone cement. The DAPI (4',6-diamidino-2-phenylindole) staining demonstrated better spreading and attachment of MG63 cells on PMMA-PCL/FA/GO surface compared to the PMMA-PCL bone cements. These results confirm the suitable mechanical properties and favorable bioactivity along with high cells viability of PMMA-PCL/FA/GO bone cement, indicating its potentials for orthopedic applications. Copyright © 2018 Elsevier Ltd. All rights reserved.

Antibiotic-eluting hydrophilized PMMA bone cement with prolonged bactericidal effect for the treatment of osteomyelitis.

PubMed

Oh, Eun Jo; Oh, Se Heang; Lee, In Soo; Kwon, Oh Soo; Lee, Jin Ho

2016-05-01

Osteomyelitis is still considered to be one of the major challenges for orthopedic surgeons despite advanced antiseptic surgical procedures and pharmaceutical therapeutics. In this study, hydrophilized poly(methyl methacrylate) (PMMA) bone cements containing Pluronic F68 (EG79PG28EG79) as a hydrophilic additive and vancomycin (F68-VAcements) were prepared to allow the sustained release of the antibiotic for adequate periods of time without any significant loss of mechanical properties. The compressive strengths of the bone cements with Pluronic F68 compositions less than 7 wt% were not significantly different compared with the control vancomycin-loaded bone cement (VAcement). TheF68 (7 wt%)-VAcement showed sustained release of the antibiotic for up to 11 weeks and almost 100% release from the bone cement. It also prohibited the growth ofS. aureus(zone of inhibition) over six weeks (the required period to treat osteomyelitis), and it did not show any notable cytotoxicity. From an animal study using a femoral osteomyelitis rat model, it was observed that theF68 (7 wt%)-VAcement was effective for the treatment of osteomyelitis, probably as a result of the prolonged release of antibiotic from the PMMA bone cement. On the basis of these findings, it can be suggested that the use of Pluronic F68 as a hydrophilic additive for antibiotic-eluting PMMA bone cement can be a promising strategy for the treatment of osteomyelitis. © The Author(s) 2016.

Micro-mechanical modeling of the cement-bone interface: the effect of friction, morphology and material properties on the micromechanical response.

PubMed

Janssen, Dennis; Mann, Kenneth A; Verdonschot, Nico

2008-11-14

In order to gain insight into the micro-mechanical behavior of the cement-bone interface, the effect of parametric variations of frictional, morphological and material properties on the mechanical response of the cement-bone interface were analyzed using a finite element approach. Finite element models of a cement-bone interface specimen were created from micro-computed tomography data of a physical specimen that was sectioned from an in vitro cemented total hip arthroplasty. In five models the friction coefficient was varied (mu=0.0; 0.3; 0.7; 1.0 and 3.0), while in one model an ideally bonded interface was assumed. In two models cement interface gaps and an optimal cement penetration were simulated. Finally, the effect of bone cement stiffness variations was simulated (2.0 and 2.5 GPa, relative to the default 3.0 GPa). All models were loaded for a cycle of fully reversible tension-compression. From the simulated stress-displacement curves the interface deformation, stiffness and hysteresis were calculated. The results indicate that in the current model the mechanical properties of the cement-bone interface were caused by frictional phenomena at the shape-closed interlock rather than by adhesive properties of the cement. Our findings furthermore show that in our model maximizing cement penetration improved the micromechanical response of the cement-bone interface stiffness, while interface gaps had a detrimental effect. Relative to the frictional and morphological variations, variations in the cement stiffness had only a modest effect on the micro-mechanical behavior of the cement-bone interface. The current study provides information that may help to better understand the load-transfer mechanisms taking place at the cement-bone interface.

Bone scans after total knee arthroplasty in asymptomatic patients. Cemented versus cementless

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hofmann, A.A.; Wyatt, R.W.; Daniels, A.U.

1990-02-01

The natural history of bone scans after total knee arthroplasty (TKA) was studied in 26 patients with 28 cemented TKAs and 29 patients with 31 cementless TKAs. The bone scans were examined at specified postoperative intervals. Radionuclide activity of the femoral, tibial, and patellar regions was measured. Six patients who developed pain postoperatively were excluded. Bone scans immediately postoperative and at three months demonstrated increased uptake, which gradually decreased to baseline levels at ten to 12 months. Radioisotope uptake was comparable in the cemented and cementless groups, but was highly variable in individual patients and in each of the follow-upmore » periods. A single postoperative bone scan cannot differentiate component loosening from early bone remodeling. Sequential bone scans, as a supplement to the clinical examination and conventional radiography, may prove useful in the diagnosis of TKA failure.« less

Extended fatigue life of a catalyst-free self-healing acrylic bone cement using microencapsulated 2-octyl cyanoacrylate

PubMed Central

Brochu, Alice B.W.; Matthys, Oriane B.; Craig, Stephen L.; Reichert, William M.

2014-01-01

The tissue adhesive 2-octyl cyanoacrylate (OCA) was encapsulated in polyurethane microshells and incorporated into bone cement to form a catalyst free, self-healing bone cement comprised of all clinically approved components. The bending strength, modulus, and fatigue lifetime were investigated in accordance with ASTM and ISO standards for the testing of PMMA bone cement. The bending strength of bone cement specimens decreased with increasing wt% capsules content for capsules without or with OCA, with specimens of < 5 wt% capsule content showing minimal effect. In contrast, bone cement bending modulus was insensitive to capsule content. Load controlled fatigue testing was performed in air at room temperature on capsule free bone cement (0 wt%), bone cement with 5 wt% OCA-free capsules (5 wt% No OCA), and 5 wt% OCA-containing capsules (5 wt% OCA). Specimens were tested at a frequency of 5 Hz at maximum stresses of 90%, 80%, 70% and 50% of each specimen's bending strength until failure. The 5 wt% OCA exhibited significant self-healing at 70% and 50% of its reference strength (p < 0.05). Fatigue testing of all three specimen types in air at 22 MPa (50% of reference strength of the 5 wt% OCA specimens) showed that the cycles to failure of OCA-containing specimens was increased by two-fold compared to the OCA-free and capsule-free specimens. This study represents the first demonstration of dynamic, catalyst-free self-healing in a biomaterial formulation. PMID:24825796

Creep behavior of bone cement: a method for time extrapolation using time-temperature equivalence.

PubMed

Morgan, R L; Farrar, D F; Rose, J; Forster, H; Morgan, I

2003-04-01

The clinical lifetime of poly(methyl methacrylate) (PMMA) bone cement is considerably longer than the time over which it is convenient to perform creep testing. Consequently, it is desirable to be able to predict the long term creep behavior of bone cement from the results of short term testing. A simple method is described for prediction of long term creep using the principle of time-temperature equivalence in polymers. The use of the method is illustrated using a commercial acrylic bone cement. A creep strain of approximately 0.6% is predicted after 400 days under a constant flexural stress of 2 MPa. The temperature range and stress levels over which it is appropriate to perform testing are described. Finally, the effects of physical aging on the accuracy of the method are discussed and creep data from aged cement are reported.

Development of calcium phosphate cement using chitosan and citric acid for bone substitute materials.

PubMed

Yokoyama, Atsuro; Yamamoto, Satoru; Kawasaki, Takao; Kohgo, Takao; Nakasu, Masanori

2002-02-01

We developed a calcium phosphate cement that could be molded into any desired shape due to its chewing-gum-like consistency after mixing. The powder component of the cement consists of alpha-tricalcium phosphate and tetracalcium phosphate, which were made by decomposition of hydroxyapatite ceramic blocks. The liquid component consists of citric acid, chitosan and glucose solution. In this study, we used 20% citric acid (group 20) and 45% citric acid (group 45). The mechanical properties and biocompatibility of this new cement were investigated. The setting times of cements were 5.5 min, in group 20 and 6.4 min, in group 45. When incubated in physiological saline, the cements were transformed to hydroxyapatite at 3, and 6 weeks, the compressive strengths were 15.6 and 20.7 MPa, in group 45 and group 20, respectively. The inflammatory response around the cement implanted on the bone and in the subcutaneous tissue in rats was more prominent in group 45 than in group 20 at 1 week after surgery. After 4 weeks, the inflammation disappeared and the cement had bound to bone in both groups. These results indicate that this new calcium phosphate cement is a suitable bone substitute material and that the concentration of citric acid in the liquid component affects its mechanical properties and biocompatibility.

Comparison of an experimental bone cement with surgical Simplex P, Spineplex and Cortoss.

PubMed

Boyd, D; Towler, M R; Wren, A; Clarkin, O M

2008-04-01

Conventional polymethylmethacrylate (PMMA) cements and more recently Bisphenol-a-glycidyl dimethacrylate (BIS-GMA) composite cements are employed in procedures such as vertebroplasty. Unfortunately, such materials have inherent drawbacks including, a high curing exotherm, the incorporation of toxic components in their formulations, and critically, exhibit a modulus mismatch between cement and bone. The literature suggests that aluminium free, zinc based glass polyalkenoate cements (Zn-GPC) may be suitable alternative materials for consideration in such applications as vertebroplasty. This paper, examines one formulation of Zn-GPC and compares its strengths, modulus, and biocompatibility with three commercially available bone cements, Spineplex, Simplex P and Cortoss. The setting times indicate that the current formulation of Zn-GPC sets in a time unsuitable for clinical deployment. However during setting, the peak exotherm was recorded to be 33 degrees C, the lowest of all cements examined, and well below the threshold level for tissue necrosis to occur. The data obtained from mechanical testing shows the Zn-GPC has strengths of 63 MPa in compression and 30 MPa in biaxial flexure. Importantly these strengths remain stable with maturation; similar long term stability was exhibited by both Spineplex and Simplex P. Conversely, the strengths of Cortoss were observed to rapidly diminish with time, a cause for clinical concern. In addition to strengths, the modulus of each material was determined. Only the Zn-GPC exhibited a modulus similar to vertebral trabecular bone, with all commercial materials exhibiting excessively high moduli. Such data indicates that the use of Zn-GPC may reduce adjacent fractures. The final investigation used the well established simulated body fluid (SBF) method to examine the ability of each material to bond with bone. The results indicate that the Zn-GPC is capable of producing a bone like apatite layer at its surface within 24 h which

A novel strontium(II)-modified calcium phosphate bone cement stimulates human-bone-marrow-derived mesenchymal stem cell proliferation and osteogenic differentiation in vitro.

PubMed

Schumacher, M; Lode, A; Helth, A; Gelinsky, M

2013-12-01

In the present study, the in vitro effects of novel strontium-modified calcium phosphate bone cements (SrCPCs), prepared using two different approaches on human-bone-marrow-derived mesenchymal stem cells (hMSCs), were evaluated. Strontium ions, known to stimulate bone formation and therefore already used in systemic osteoporosis therapy, were incorporated into a hydroxyapatite-forming calcium phosphate bone cement via two simple approaches: incorporation of strontium carbonate crystals and substitution of Ca(2+) by Sr(2+) ions during cement setting. All modified cements released 0.03-0.07 mM Sr(2+) under in vitro conditions, concentrations that were shown not to impair the proliferation or osteogenic differentiation of hMSCs. Furthermore, strontium modification led to a reduced medium acidification and Ca(2+) depletion in comparison to the standard calcium phosphate cement. In indirect and direct cell culture experiments with the novel SrCPCs significantly enhanced cell proliferation and differentiation were observed. In conclusion, the SrCPCs described here could be beneficial for the local treatment of defects, especially in the osteoporotic bone. Copyright © 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Evaluation of rhBMP-2/collagen/TCP-HA bone graft with and without bone marrow cells in the canine femoral multi defect model.

PubMed

Luangphakdy, V; Shinohara, K; Pan, H; Boehm, C; Samaranska, A; Muschler, G F

2015-01-12

Recombinant human bone morphogenetic protein-2, when applied to an absorbable type 1 bovine collagen sponge (rhBMP-2/ACS) is an effective therapy in many bone grafting settings. Bone marrow aspirate (BMA) has also been used as a source of transplantable osteogenic connective tissue progenitors. This study was designed to characterize the performance of a scaffold comprising rhBMP-2/ACS in which the sponge wraps around tri-calcium phosphate hydroxyapatite granules (rhBMP-2/ACS/TCP-HA) and to test the hypothesis that addition of BMA will improve the performance of this construct in the Canine Femoral Multi Defect Model. In each subject, two sites were grafted with rhBMP-2/ACS/TCP-HA scaffold loaded with BMA clot and two other sites with rhBMP-2/ACS/TCP-HA scaffold loaded with wound blood (WB). After correction for unresorbed TCP-HA granules, sites grafted with rhBMP-2/ACS/TCP-HA+BMA and rhBMP-2/ACS/TCP-HA+WB were similar, with mean percent bone volumes of 10.9 %±1.2 and 11.2 %±1.2, respectively. No differences were seen in quantitative histomorphometry. While bone formation using both constructs was robust, this study did not support the hypothesis that the addition of unprocessed bone marrow aspirate clot improved bone regeneration in a site engrafted with rhBMP-2/ACS/TCP-HA+BMA. In contrast to prior studies using this model, new bone formation was greater at the center of the defect where TCP-HA was distributed. This finding suggests a potential synergy between rhBMP-2 and the centrally placed ceramic and cellular components of the graft construct. Further optimization may also require more uniform distribution of TCP-HA, alternative cell delivery strategies, and a more rigorous large animal segmental defect model.

[Correlation analysis of cement leakage with volume ratio of intravertebral bone cement to vertebral body and vertebral body wall incompetence in percutaneous vertebroplasty for osteoporotic vertebral compression fractures].

PubMed

Liang, De; Ye, Linqiang; Jiang, Xiaobing; Huang, Weiquan; Yao, Zhensong; Tang, Yongchao; Zhang, Shuncong; Jin, Daxiang

2014-11-01

To investigate the risk factors of cement leakage in percutaneous vertebroplasty (PVP) for osteoporotic vertebral compression fracture (OVCF). Between March 2011 and March 2012, 98 patients with single level OVCF were treated by PVP, and the clinical data were analyzed retrospectively. There were 13 males and 85 females, with a mean age of 77.2 years (range, 54-95 years). The mean disease duration was 43 days (range, 15-120 days), and the mean T score of bone mineral density (BMD) was -3.8 (range, -6.7- -2.5). Bilateral transpedicular approach was used in all the patients. The patients were divided into cement leakage group and no cement leakage group by occurrence of cement leakage based on postoperative CT. Single factor analysis was used to analyze the difference between 2 groups in T score of BMD, operative level, preoperative anterior compression degree of operative vertebrae, preoperative middle compression degree of operative vertebrae, preoperative sagittal Cobb angle of operative vertebrae, preoperative vertebral body wall incompetence, cement volume, and volume ratio of intravertebral bone cement to vertebral body. All relevant factors were introduced to logistic regression analysis to analyze the risk factors of cement leakage. All procedures were performed successfully. The mean operation time was 40 minutes (range, 30-50 minutes), and the mean volume ratio of intravertebral bone cement to vertebral body was 24.88% (range, 7.84%-38.99%). Back pain was alleviated significantly in all the patients postoperatively. All patients were followed up with a mean time of 8 months (range, 6-12 months). Cement leakage occurred in 49 patients. Single factor analysis showed that there were significant differences in the volume ratio of intravertebral bone cement to vertebral body and preoperative vertebral body wall incompetence between 2 groups (P < 0.05), while no significant difference in T score of BMD, operative level, preoperative anterior compression degree of

Evaluation of Different Experience Levels of Orthopaedic Residents Effect on Polymethylmethacrylate (PMMA) Bone Cement Mechanical Properties.

PubMed

Struemph, Jonathon M; Chong, Alexander C M; Wooley, Paul H

2015-01-01

PMMA bone cement is a brittle material and the creation of defects that increase porosity during mixing or injecting is a significant factor in reducing its mechanical properties. The goal during residency training is to learn how to avoid creating increased porosity during mixing and injecting the material. The aim of this study was to evaluate and compare tensile and compression strength for PMMA cement mixed by intern orthopaedic residents (PGY-1) and senior orthopaedic residents (PGY-5). The hypothesis was that the mechanical properties of PMMA cement mixed by PGY-5 would be significantly better than PMMA cement mixed by PGY-1 residents. Four PGY-1 and four PGY-5 orthopaedic residents each prepared eight tensile specimens. The bone cement used was Simplex™ P bone cement (Stryker Howmedica Osteonics, Mahwah, NJ) under vacuum mixing in a cement-delivery system. Tensile testing of the specimens was performed in an MTS Bionix servohydraulic materials testing system with loading rate of 2.54 mm/min at room temperature. The mean and standard deviation of the ultimate tensile strength (UTS) for each orthopaedic resident group was calculated. The compression specimens were cylinders formed with a central core to mimic a prosthetic implant. Ten samples from each orthopaedic resident were tested using the same MTS system under identical conditions at room temperature. The specimens were loaded from -50 N to complete structural failure at the rate of 20 mm/min. The ultimate compressive strength (UCS) was then determined and the mean and standard deviation calculated for each group. The average UTS of the bone cement for the PGY-1 and PGY-5 residents was 37.5 ± 4.5 MPa and 39.2 ± 5.0 MPa, respectively, and there was no statistically significant difference between the two groups. For the tensile elastic modulus of the bone cement, the results for the PGY-1 and PGY-5 residents were 2.40 ± 0.09 GPa and 2.44 ± 0.08 GPa, respectively, and again there was no statistically

Torque test measurement in segmental bone defects using porous calcium phosphate cement implants.

PubMed

Kroese-Deutman, Henriette C; Wolke, Joop G C; Spauwen, Paul H M; Jansen, John A

2010-10-01

This study was performed to assess the bone healing supporting characteristics of porous calcium phosphate (Ca-P) cement when implanted in a rabbit segmental defect model as well as to determine the reliability of torque testing as a method to verify bone healing. The middiaphyseal radius was chosen as the area to create bilaterally increasing defect sizes (5, 10, and 15 mm), which were either filled with porous Ca-P cement or left open as a control. After 12 weeks of implantation, torque test measurements as well as histological and radiographic evaluation were performed. In two of the open 15 mm control defects, bone bridging was visible at the radiographic and histological evaluation. Bone was observed to be present in all porous Ca-P cement implants (5, 10, and 15 mm defects) after 12 weeks. No significant differences in torque measurements were observed between the 5 and 10 mm filled and open control defects using a t-test. In addition, the mechanical strength of all operated specimens was similar compared with nonoperated bone samples. The torsion data for the 15 mm open defect appeared to be lower compared with the filled 15 mm defect, but no significant difference could be proven. Within the limitation of the study design, porous Ca-P cement implants demonstrated osteoconductive properties and confirmed to be a suitable scaffold material in a weight-bearing situation. Further, the used torque testing method was found to be unreliable for testing the mechanical properties of the healed bone defect.

Assessment of bone healing ability of calcium phosphate cements loaded with platelet lysate in rat calvarial defects.

PubMed

Babo, Pedro S; Carvalho, Pedro P; Santo, Vítor E; Faria, Susana; Gomes, Manuela E; Reis, Rui L

2016-11-01

Injectable calcium phosphate cements have been used as a valid alternative to autologous bone grafts for bone augmentation with the additional advantage of enabling minimally invasive implantation procedures and for perfectly fitting the tissue defect. Nevertheless, they have low biodegradability and lack adequate biochemical signaling to promote bone healing and remodeling. In previous in vitro studies, we observed that the incorporation of platelet lysate directly into the cement paste or loaded in hyaluronic acid microspheres allowed to modulate the cement degradation and the in vitro expression of osteogenic markers in seeded human adipose derived stem cells. The present study aimed at investigating the possible effect of this system in new bone formation when implanted in calvarial bilateral defects in rats. Different formulations were assessed, namely plain calcium phosphate cements, calcium phosphate cements loaded with human platelet lysate, hybrid injectable formulations composed of the calcium phosphate cement incorporating hyaluronin acid non-loaded microparticles (20% hyaluronin acid) or with particles loaded with platelet lysate. The degradability and new bone regrowth were evaluated in terms of mineral volume in the defect, measured by micro-computed tomography and histomorphometric analysis upon 4, 8 and 12 weeks of implantation. We observed that the incorporation of hyaluronin acid microspheres induced an overly rapid cement degradation, impairing the osteoconductive properties of the cement composites. Moreover, the incorporation of platelet lysate induced higher bone healing than the materials without platelet lysate, up to four weeks after surgery. Nevertheless, this effect was not found to be significant when compared to the one observed in the sham-treated group. © The Author(s) 2016.

Physical characterization and osteogenic activity of the quaternized chitosan-loaded PMMA bone cement.

PubMed

Tan, Honglue; Guo, Shengrong; Yang, Shengbing; Xu, Xiaofen; Tang, Tingting

2012-07-01

Gentamicin-loaded polymethylmethacrylate (PMMA), widely used for primary cemented arthroplasty and revision surgery for preventing or treating infections, may lead to the evolution of antibiotic-resistant bacteria and dysfunction of osteogenic cells, which further influence the osteointegration of bone cement. In a previous study, we reported that a new quaternized chitosan derivative (hydroxypropyltrimethyl ammonium chloride chitosan, HACC) that was loaded into PMMA significantly inhibited the formation of biofilms caused by methicillin-resistant Staphylococcus strains. In the present study, we further investigated the surface morphology, hydrophilicity, apatite formation ability and osteogenic activity of HACC-loaded PMMA. Chitosan-loaded PMMA, gentamicin-loaded PMMA and PMMA without antibiotic were also investigated and compared. The results showed that, compared to other PMMA-based cements, HACC-loaded PMMA had improved properties such as a lower polymerization temperature, prolonged setting time, porous structures after immersion in phosphate-buffered saline, higher hydrophilicity, more apatite formation on the surface after immersion in simulated body fluid, and better attachment and spreading of the human-marrow-derived mesenchymal stem cells. We also found better stem cell proliferation, osteogenic differentiation, and osteogenesis-associated genes expression on the surface of the HACC-loaded PMMA compared to the gentamicin-loaded PMMA. Therefore, this new anti-infective bone cement had improved physical properties and osteogenic activity, which may lead to better osteointegration of the bone cement in cemented arthroplasty. Copyright © 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

New method for antibiotic release from bone cement (polymethylmethacrylate): Redefining boundaries.

PubMed

Carbó-Laso, E; Sanz-Ruiz, P; Del Real-Romero, J C; Ballesteros-Iglesias, Y; Paz-Jiménez, E; Arán-Ais, F; Sánchez-Navarro, M; Pérez-Limiñana, M A; López-Torres, I; Vaquero-Martín, J

The increasing antimicrobial resistance is promoting the addition of antibiotics with high antistaphylococcal activity to polymethylmethacrylate (PMMA), for use in cement spacers in periprosthetic joint infection. Linezolid and levofloxacin have already been used in in-vitro studies, however, rifampicin has been shown to have a deleterious effect on the mechanical properties of PMMA, because it inhibits PMMA polymerization. The objective of our study was to isolate the rifampicin during the polymerization process using microencapsulation techniques, in order to obtain a PMMA suitable for manufacturing bone cement spacers. Microcapsules of rifampicin were synthesized with alginate and PHBV, using Rifaldin ® . The concentration levels of rifampicin were studied by UV-visible spectrophotometry. Compression, hardness and setting time tests were performed with CMW ® 1 cement samples alone, with non-encapsulated rifampicin and with alginate or PHBV microcapsules. The production yield, efficiency and microencapsulation yield were greater with alginate (P = .0001). The cement with microcapsules demonstrated greater resistance to compression than the cement with rifampicin (91.26±5.13, 91.35±6.29 and 74.04±3.57 MPa in alginate, PHBV and rifampicin, respectively) (P = .0001). The setting time reduced, and the hardness curve of the cement with alginate microcapsules was similar to that of the control. Microencapsulation with alginate is an appropriate technique for introducing rifampicin into PMMA, preserving compression properties and setting time. This could allow intraoperative manufacturing of bone cement spacers that release rifampicin for the treatment of periprosthetic joint infection. Copyright © 2017 SECOT. Publicado por Elsevier España, S.L.U. All rights reserved.

Microencapsulation of rifampicin: A technique to preserve the mechanical properties of bone cement.

PubMed

Sanz-Ruiz, Pablo; Carbó-Laso, Esther; Del Real-Romero, Juan Carlos; Arán-Ais, Francisca; Ballesteros-Iglesias, Yolanda; Paz-Jiménez, Eva; Sánchez-Navarro, Magdalena; Pérez-Limiñana, María Ángeles; Vaquero-Martín, Javier

2018-01-01

Two-stage exchange with antibiotic-loaded bone cement spacers remains the gold standard for chronic periprosthetic joint infection (PJI). Rifampicin is highly efficient on stationary-phase staphylococci in biofilm; however, its addition to PMMA to manufacture spacers prevents polymerization and reduces mechanical properties. Isolation of rifampicin during polymerization by microencapsulation could allow manufacturing rifampicin-loaded bone cement maintaining elution and mechanical properties. Microcapsules of rifampicin with alginate, polyhydroxybutyratehydroxyvalerate (PHBV), ethylcellulose and stearic acid (SA) were synthesized. Alginate and PHBV microcapsules were added to bone cement and elution, compression, bending, hardness, setting time and microbiological tests were performed. Repeated measures ANOVA and Bonferroni post-hoc test were performed, considering a p < 0.05 as statistical significance. Bone cement specimens containing alginate microcapsules eluted more rifampicin than PHBV microcapsules or non-encapsulated rifampicin over time (p < 0.012). Microencapsulation of rifampicin allowed PMMA to preserve mechanical properties in compression and bending tests. Cement with alginate microcapsules showed similar behavior in hardness tests to control cement over the study period (73 ± 1.68H D ). PMMA with alginate microcapsules exhibited the largest zones of inhibition in microbiological tests. Statistically significant differences in mean diameters of zones of inhibition between PMMA loaded with alginate-rifampicin (p = 0.0001) and alginate-PHBV microcapsules (p = 0.0001) were detected. Rifampicin microencapsulation with alginate is the best choice to introduce rifampicin in PMMA preserving mechanical properties, setting time, elution, and antimicrobial properties. The main applicability of this study is the opportunity for obtaining rifampicin-loaded PMMA by microencapsulation of rifampicin in alginate microparticles, achieving high

Activity of Fosfomycin- and Daptomycin-Containing Bone Cement on Selected Bacterial Species Being Associated with Orthopedic Infections.

PubMed

Eick, Sigrun; Hofpeter, Kevin; Sculean, Anton; Ender, Claudia; Klimas, Susann; Vogt, Sebastian; Nietzsche, Sandor

2017-01-01

The purpose of this study was to determine activity of fosfomycin/gentamicin and daptomycin/gentamicin-containing PMMA bone-cement against Staphylococcus aureus (MRSA, MSSA), Staphylococcus epidermidis , Enterococcus faecium (VRE), and E. coli (ESBL; only fosfomycin). Test specimens of the bone cement were formed and bacteria in two concentrations were added one time or repeatedly up to 96 h. All fosfomycin-containing cement killed ultimately all MSSA, Staphylococcus epidermidis, and E. coli within 24 h; growth of MRSA was suppressed up to 48 h. Activity of daptomycin-containing cement depended on the concentration; the highest concentrated bone cement used (1.5 g daptomycin/40 g of powder) was active against all one-time added bacteria. When bacteria were added repeatedly to fosfomycin-containing cement, growth was suppressed up to 96 h and that of MRSA and VRE only up to 24 h. The highest concentration of daptomycin suppressed the growth of repeated added bacteria up to 48 h (VRE) until 96 h (MSSA, MRSA). In conclusion, PMMA bone cement with 1.5 g of daptomycin and 0.5 g of gentamicin may be an alternative in treatment of periprosthetic infections caused by Gram-positive bacteria.

Activity of Fosfomycin- and Daptomycin-Containing Bone Cement on Selected Bacterial Species Being Associated with Orthopedic Infections

PubMed Central

Hofpeter, Kevin; Sculean, Anton; Ender, Claudia; Klimas, Susann; Vogt, Sebastian; Nietzsche, Sandor

2017-01-01

The purpose of this study was to determine activity of fosfomycin/gentamicin and daptomycin/gentamicin-containing PMMA bone-cement against Staphylococcus aureus (MRSA, MSSA), Staphylococcus epidermidis, Enterococcus faecium (VRE), and E. coli (ESBL; only fosfomycin). Test specimens of the bone cement were formed and bacteria in two concentrations were added one time or repeatedly up to 96 h. All fosfomycin-containing cement killed ultimately all MSSA, Staphylococcus epidermidis, and E. coli within 24 h; growth of MRSA was suppressed up to 48 h. Activity of daptomycin-containing cement depended on the concentration; the highest concentrated bone cement used (1.5 g daptomycin/40 g of powder) was active against all one-time added bacteria. When bacteria were added repeatedly to fosfomycin-containing cement, growth was suppressed up to 96 h and that of MRSA and VRE only up to 24 h. The highest concentration of daptomycin suppressed the growth of repeated added bacteria up to 48 h (VRE) until 96 h (MSSA, MRSA). In conclusion, PMMA bone cement with 1.5 g of daptomycin and 0.5 g of gentamicin may be an alternative in treatment of periprosthetic infections caused by Gram-positive bacteria. PMID:28484708

Influence of different modifications of a calcium phosphate bone cement on adhesion, proliferation, and osteogenic differentiation of human bone marrow stromal cells.

PubMed

Vater, Corina; Lode, Anja; Bernhardt, Anne; Reinstorf, Antje; Heinemann, Christiane; Gelinsky, Michael

2010-03-15

Collagen and noncollagenous proteins of the extracellular bone matrix are able to stimulate bone cell activities and bone healing. The modification of calcium phosphate bone cements used as temporary bone replacement materials with these proteins seems to be a promising approach to accelerate new bone formation. In this study, we investigated adhesion, proliferation, and osteogenic differentiation of human bone marrow stromal cells (hBMSC) on Biocement D/collagen composites which have been modified with osteocalcin and O-phospho-L-serine. Modification with osteocalcin was carried out by its addition to the cement precursor before setting as well as by functionalization of the cement samples after setting and sterilization. hBMSC were cultured on these samples for 28 days with and without osteogenic supplements. We found a positive impact especially of the phosphoserine-modifications but also of both osteocalcin-modifications on differentiation of hBMSC indicated by higher expression of the osteoblastic markers matrix metalloproteinase-13 and bone sialo protein II. For hBMSC cultured on phosphoserine-containing composites, an increased proliferation has been observed. However, in case of the osteocalcin-modified samples, only osteocalcin adsorbed after setting and sterilization of the cement samples was able to promote initial adhesion and proliferation of hBMSC. The addition of osteocalcin before setting results in a finer microstructure but the biological activity of osteocalcin might be impaired due to the sterilization process. Thus, our data indicate that the initial adhesion and proliferation of hBMSC is enhanced rather by the biological activity of osteocalcin than by the finer microstructure. (c) 2009 Wiley Periodicals, Inc.

Experimental studies on a new bioactive material: HAIonomer cements.

PubMed

Yap, A U J; Pek, Y S; Kumar, R A; Cheang, P; Khor, K A

2002-02-01

The lack of exotherm during setting, absence of monomer and improved release of incorporated therapeutic agents has resulted in the development of glass ionomer cements (GICs) for biomedical applications. In order to improve biocompatibility and biomechanically match GICs to bone, hydroxyapatite-ionomer (HAIonomer) hybrid cements were developed. Ultra-fine hydroxyapatite (HA) powders were produced using a new induction spraying technique that utilizes a radio-frequency source to spheriodize an atomized suspension containing HA crystallites. The spheriodized particulates were then held at 800 degrees C for 4 h in a carbolite furnace using a heating and cooling rate of 25 degrees C/min to obtain almost fully crystalline HA powders. The heat-treated particles were characterized and introduced into a commercial glass ionomer cement. 4 (H4), 12 (H12) and 28 (H28) vol% of fluoroalumino silicate were substituted by crystalline HA particles that were dispersed using a high-speed dispersion technique. The HAIonomer cements were subjected to hardness, compressive and diametral tensile strength testing based upon BS6039:1981. The storage time were extended to one week to investigate the effects of cement maturation on mechanical properties. Commercially available capsulated GIC (GC) and GIC at maximum powder:liquid ratio (GM) served as comparisons. Results were analyzed using factorial ANOVA/Scheffe's post-hoc tests and independent samples t-test at significance level 0.05. The effect of time on hardness was material dependent. With the exception of H12, a significant increase in hardness was observed for all materials at one week. A significant increase in compressive strength was, however, observed for H12 over time. At 1 day and 1 week, the hardness of H28 was significantly lower than for GM, H4, and H12. No significant difference in compression and diametral tensile strengths were observed between materials at both time intervals. Results show that HAIonomers is a

Evaluation of an injectable bioactive borate glass cement to heal bone defects in a rabbit femoral condyle model.

PubMed

Cui, Xu; Huang, Wenhai; Zhang, Yadong; Huang, Chengcheng; Yu, Zunxiong; Wang, Lei; Liu, Wenlong; Wang, Ting; Zhou, Jie; Wang, Hui; Zhou, Nai; Wang, Deping; Pan, Haobo; Rahaman, Mohamed N

2017-04-01

There is a need for synthetic biomaterials to heal bone defects using minimal invasive surgery. In the present study, an injectable cement composed of bioactive borate glass particles and a chitosan bonding solution was developed and evaluated for its capacity to heal bone defects in a rabbit femoral condyle model. The injectability and setting time of the cement in vitro decreased but the compressive strength increased (8±2MPa to 31±2MPa) as the ratio of glass particles to chitosan solution increased (from 1.0gml -1 to 2.5gml -1 ). Upon immersing the cement in phosphate-buffered saline, the glass particles reacted and converted to hydroxyapatite, imparting bioactivity to the cement. Osteoblastic MC3T3-E1 cells showed enhanced proliferation and alkaline phosphatase activity when incubated in media containing the soluble ionic product of the cement. The bioactive glass cement showed a better capacity to stimulate bone formation in rabbit femoral condyle defects at 12weeks postimplantation when compared to a commercial calcium sulfate cement. The injectable bioactive borate glass cement developed in this study could provide a promising biomaterial to heal bone defects by minimal invasive surgery. Copyright © 2016 Elsevier B.V. All rights reserved.

Bone cement distribution is a potential predictor to the reconstructive effects of unilateral percutaneous kyphoplasty in OVCFs: a retrospective study.

PubMed

Lin, Jiachen; Qian, Lie; Jiang, Changqing; Chen, Xiuyuan; Feng, Fan; Lao, Lifeng

2018-06-07

Osteoporotic vertebral compression fracture (OVCF) is a common type of fracture, and percutaneous kyphoplasty (PKP) is an eligible solution to it. Previous studies have revealed that both the volume and filling pattern of bone cement correlate with the clinical outcomes after PKP procedure. However, the role of bone cement distribution remains to be illustrated. To retrospectively evaluate the relationship between the bone cement distribution and the clinical outcomes of unilateral PKP, we enrolled 73 OVCF patients receiving unilateral PKP treatment. All the intervened vertebrae were classified into three groups based on the bone cement distribution observed on postoperative X-ray films. Preoperative and postoperative radiographic parameters including the vertebral height and kyphotic Cobb angle were recorded, and anterior vertebral height restoration rate (AVHRR) and Cobb angle correction (CR) were then calculated to assess the vertebral height reconstruction. Preoperative and postoperative Oswestry Disability Index (ODI) and visual analogue scale (VAS) were adopted by interviewing patients to assess the mobility improvement and pain relief. Demographic data, body mass index (BMI), lumbar bone mineral density (evaluated by BMD T-score) of each patient, bone cement volume (BV), and bone cement extravasation (BE) were also recorded. Between- and within-group comparisons and multivariable correlation analysis were carried out to analyze the data. VAS and ODI scores were both significantly improved in all of the enrolled cases with no significant differences between groups. Among the three groups, the average age, AVHRR, and BV were significantly different. Occurrence of BE was significantly different between two of the three groups. AVHRR was demonstrated to correlate negatively with preoperative anterior vertebral height ratio and positively with preoperative Cobb angle, CR, diffusion score, and ODI changes. Bone cement distribution is a potential predictor to the

BoneSource hydroxyapatite cement: a novel biomaterial for craniofacial skeletal tissue engineering and reconstruction.

PubMed

Friedman, C D; Costantino, P D; Takagi, S; Chow, L C

1998-01-01

BoneSource-hydroxyapatite cement is a new self-setting calcium phosphate cement biomaterial. Its unique and innovative physical chemistry coupled with enhanced biocompatibility make it useful for craniofacial skeletal reconstruction. The general properties and clinical use guidelines are reviewed. The biomaterial and surgical applications offer insight into improved outcomes and potential new uses for hydroxyapatite cement systems.

Hierarchical Structure and Mechanical Improvement of an n-HA/GCO-PU Composite Scaffold for Bone Regeneration.

PubMed

Li, Limei; Zuo, Yi; Zou, Qin; Yang, Boyuan; Lin, Lili; Li, Jidong; Li, Yubao

2015-10-14

To improve the mechanical properties of bone tissue and achieve the desired bone tissue regeneration for orthopedic surgery, newly designed hydroxyapatite/polyurethane (HA/PU) porous scaffolds were developed via in situ polymerization. The results showed that the molecular modification of PU soft segments by glyceride of castor oil (GCO) can increase the scaffold compressive strength by 48% and the elastic modulus by 96%. When nano-HA (n-HA) particles were incorporated into the GCO-PU matrix, the compressive strength and elastic modulus further increased by 49 and 74%, from 2.91 to 4.34 MPa and from 95 to 165.36 MPa, respectively. The n-HA particles with fine dispersity not only improved the interface bonding with the GCO-PU matrix but also provided effective bioactivity for bonding with bone tissue. The hierarchical structure and mechanical quality of the n-HA/GCO-PU composite scaffold were determined to be appropriate for the growth of cells and the regeneration of bony tissues, demonstrating promising prospects for bone repair and regeneration.

Silver-Doped Calcium Phosphate Bone Cements with Antibacterial Properties

PubMed Central

Rau, J. V.; Fosca, M.; Graziani, V.; Egorov, A. A.; Zobkov, Yu. V.; Fedotov, A. Yu.; Ortenzi, M.; Caminiti, R.; Baranchikov, A. E.; Komlev, V. S.

2016-01-01

Calcium phosphate bone cements (CPCs) with antibacterial properties are demanded for clinical applications. In this study, we demonstrated the use of a relatively simple processing route based on preparation of silver-doped CPCs (CPCs-Ag) through the preparation of solid dispersed active powder phase. Real-time monitoring of structural transformations and kinetics of several CPCs-Ag formulations (Ag = 0 wt %, 0.6 wt % and 1.0 wt %) was performed by the Energy Dispersive X-ray Diffraction technique. The partial conversion of β-tricalcium phosphate (TCP) phase into the dicalcium phosphate dihydrate (DCPD) took place in all the investigated cement systems. In the pristine cement powders, Ag in its metallic form was found, whereas for CPC-Ag 0.6 wt % and CPC-Ag 1.0 wt % cements, CaAg(PO3)3 was detected and Ag (met.) was no longer present. The CPC-Ag 0 wt % cement exhibited a compressive strength of 6.5 ± 1.0 MPa, whereas for the doped cements (CPC-Ag 0.6 wt % and CPC-Ag 1.0 wt %) the reduced values of the compressive strength 4.0 ± 1.0 and 1.5 ± 1.0 MPa, respectively, were detected. Silver-ion release from CPC-Ag 0.6 wt % and CPC-Ag 1.0 wt % cements, measured by the Atomic Emission Spectroscopy, corresponds to the average values of 25 µg/L and 43 µg/L, respectively, rising a plateau after 15 days. The results of the antibacterial test proved the inhibitory effect towards pathogenic Escherichia coli for both CPC-Ag 0.6 wt % and CPC-Ag 1.0 wt % cements, better performances being observed for the cement with a higher Ag-content. PMID:27096874

Effect of shape on bone cement polymerization time in knee joint replacement surgery

PubMed Central

Yoon, Jung-Ro; Ko, Young-Rok; Shin, Young-Soo

2018-01-01

Abstract Background: Although many factors are known to influence the polymerization time of bone cement, it remains unclear which bone cement shape predicts the precise polymerization time. The purpose of this study was to investigate whether different cement shapes influenced polymerization time and to identify the relationship between cement shape and ambient operating theater temperature, relative humidity, and equilibration time. Methods: Samples were gathered prospectively from 237 patients undergoing primary total knee arthroplasty. The cement components were made into 2 different shapes: lump and pan. The time at which no macroscopic indentation of both cement models was possible was recorded as the polymerization time. Results: There was no significant difference between hand mixing (lump shape: 789.3 ± 128.4 seconds, P = .591; pan shape: 899.3 ± 152.2 seconds, P = .584) and vacuum mixing (lump shape: 780.2 ± 131.1 seconds, P = .591; pan shape: 909.9 ± 143.3 seconds, P = .584) in terms of polymerization time. Conversely, the polymerization time was significantly shorter for Antibiotic Simplex (lump shape: 757.4 ± 114.9 seconds, P = .001; pan shape: 879.5 ± 125.0 seconds, P < .001) when compared with Palacos R+G (lump shape: 829.0 ± 139.3 seconds, P = .001; pan shape: 942.9 ± 172.0 seconds, P < .001). Polymerization time was also significantly longer (P < .001) for the pan shape model (904 ± 148.0 seconds) when compared with the lump shape model (785.2 ± 129.4 seconds). In addition, the polymerization time decreased with increasing temperature (lump shape: R2 = 0.334, P < .001; pan shape: R2 = 0.375, P < .001), humidity (lump shape: R2 = 0.091, P < .001; pan shape: R2 = 0.106, P < .001), and equilibration time (lump shape: R2 = 0.073, P < .001; pan shape: R2 = 0.044, P < .001). Conclusions: The

Effect of fabrication pressure on the fatigue performance of Cemex XL acrylic bone cement.

PubMed

Lewis, Gladius; Janna, S I

2004-01-01

During a cemented arthroplasty, the prepared polymerizing dough of acrylic bone cement is subjected to pressurization in a number of ways; first, during delivery into the freshly prepared bone bed, second, during packing in that bed (either digitally or with the aid of a mechanical device), and, third, during the insertion of the prosthesis. Only a few studies have reported on the influence of the level of pressurization experienced during these events (which, depending on the cementing technique used, has been put at between 8 and 273 kPa) on various properties of the cement. That was the focus of the present study, in which the fully reversed tension-compression (+/-15 MPa; 5 Hz) fatigue lives (expressed as number of cycles to fracture, N(f)) of rectangular cross-sectioned "dog-bone" specimens (Type V, per ASTM D 638) fabricated from Cemex XL cement, at pressure applied continuously to the cement dough during curing in the specimen mold, p=75,150, and 300 kPa, were determined. The N(f) results were analyzed using the linearized transformation of the three-parameter Weibull relationship to obtain estimates of the Weibull mean, N(WM), which was taken to be the index of fatigue performance of the specimen set. Over the range of p studied, N(WM) increased as p increased (for example, from 329,118 cycles when p was 75 kPa to 388,496 cycles when p was 300 kPa); however, the increase was not significant over any pair of p increment steps (Mann-Whitney U-test; alpha<0.05).

Reinforced Portland cement porous scaffolds for load-bearing bone tissue engineering applications.

PubMed

Higuita-Castro, Natalia; Gallego-Perez, Daniel; Pelaez-Vargas, Alejandro; García Quiroz, Felipe; Posada, Olga M; López, Luis E; Sarassa, Carlos A; Agudelo-Florez, Piedad; Monteiro, Fernando J; Litsky, Alan S; Hansford, Derek J

2012-02-01

Modified Portland cement porous scaffolds with suitable characteristics for load-bearing bone tissue engineering applications were manufactured by combining the particulate leaching and foaming methods. Non-crosslinked polydimethylsiloxane was evaluated as a potential reinforcing material. The scaffolds presented average porosities between 70 and 80% with mean pore sizes ranging from 300 μm up to 5.0 mm. Non-reinforced scaffolds presented compressive strengths and elastic modulus values of 2.6 and 245 MPa, respectively, whereas reinforced scaffolds exhibited 4.2 and 443 MPa, respectively, an increase of ∼62 and 80%. Portland cement scaffolds supported human osteoblast-like cell adhesion, spreading, and propagation (t = 1-28 days). Cell metabolism and alkaline phosphatase activity were found to be enhanced at longer culture intervals (t ≥ 14 days). These results suggest the possibility of obtaining strong and biocompatible scaffolds for bone repair applications from inexpensive, yet technologically advanced materials such as Portland cement. Copyright © 2011 Wiley Periodicals, Inc.

Contemporary adjuvant polymethyl methacrylate cementation optimally limits recurrence in primary giant cell tumor of bone patients compared to bone grafting: a systematic review and meta-analysis

PubMed Central

2013-01-01

Background Reports of recurrence following restructuring of primary giant cell tumor (GCT) defects using polymethyl methacrylate (PMMA) bone cementation or allogeneic bone graft with and without adjuvants for intralesional curettage vary widely. Systematic review and meta-analysis were conducted to investigate efficacy of PMMA bone cementation and allogeneic bone grafting following intralesional curettage for GCT. Methods Medline, EMBASE, Google Scholar, and Cochrane databases were searched for studies reporting GCT of bone treatment with PMMA cementation and/or bone grafting with or without adjuvant therapy following intralesional curettage of primary GCTs. Pooled risk ratios and 95% confidence intervals (CIs) for local recurrence risks were calculated by fixed-effects methods. Results Of 1,690 relevant titles, 6 eligible studies (1,293 patients) spanning March 2008 to December 2011 were identified in published data. Treatment outcomes of PMMA-only (n = 374), bone graft-only (n = 436), PMMA with or without adjuvant (PMMA + adjuvant; n = 594), and bone graft filling with or without adjuvant (bone graft + adjuvant; n = 699) were compared. Bone graft-only patients exhibited higher recurrence rates than PMMA-treated patients (RR 2.09, 95% CI (1.64, 2.66), Overall effect: Z = 6.00; P <0.001), and bone graft + adjuvant patients exhibited higher recurrence rates than PMMA + adjuvant patients (RR 1.66, 95% CI (1.21, 2.28), Overall effect: Z = 3.15, P = 0.002). Conclusions Local recurrence was minimal in PMMA cementation patients, suggesting that PMMA is preferable for routine clinical restructuring in eligible GCT patients. Relationships between tumor characteristics, other modern adjuvants, and recurrence require further exploration. PMID:23866921

Effects of Incorporating Carboxymethyl Chitosan into PMMA Bone Cement Containing Methotrexate

PubMed Central

Liu, Bo-Ming; Li, Ming; Yin, Bao-Sheng; Zou, Ji-Yang; Zhang, Wei-Guo; Wang, Shou-Yu

2015-01-01

Treatment of bone metastases usually includes surgical resection with local filling of methotrexate (MTX) in polymethyl methacrylate (PMMA) cement. We investigated whether incorporating carboxymethyl chitosan (CMCS) in MTX-PMMA cement might overcome disadvantages associated with MTX. To determine the optimal CMCS+MTX concentration to suppress the viability of cancer cells, an integrated microfluidic chip culturing highly metastatic lung cancer cells (H460) was employed. The mechanical properties, microstructure, and MTX release of (CMCS+MTX)-PMMA cement were evaluated respectively by universal mechanical testing machine, scanning electron microscopy (SEM), and incubation in simulated body fluid with subsequent HPLC-MS. Implants of MTX-PMMA and (CMCS+MTX)-PMMA cement were evaluated in vivo in guinea pig femurs over time using spiral computed tomography with three-dimensional image reconstruction, and SEM at 6 months. Viability of H460 cells was significantly lowest after treatment with 57 μg/mL CMCS + 21 μg/mL MTX, which was thus used in subsequent experiments. Incorporation of 1.6% (w/w) CMCS to MTX-PMMA significantly increased the bending modulus, bending strength, and compressive strength by 5, 2.8, and 5.2%, respectively, confirmed by improved microstructural homogeneity. Incorporation of CMCS delayed the time-to-plateau of MTX release by 2 days, but increased the fraction released at the plateau from 3.24% (MTX-PMMA) to 5.34%. Relative to the controls, the (CMCS+MTX)-PMMA implants integrated better with the host bone. SEM revealed pores in the cement of the (CMCS+MTX)-PMMA implants that were not obvious in the controls. In conclusion, incorporation of CMCS in MTX-PMMA appears a feasible and effective modification for improving the anti-tumor properties of MTX-PMMA cement. PMID:26657526

Effects of Incorporating Carboxymethyl Chitosan into PMMA Bone Cement Containing Methotrexate.

PubMed

Liu, Bo-Ming; Li, Ming; Yin, Bao-Sheng; Zou, Ji-Yang; Zhang, Wei-Guo; Wang, Shou-Yu

2015-01-01

Treatment of bone metastases usually includes surgical resection with local filling of methotrexate (MTX) in polymethyl methacrylate (PMMA) cement. We investigated whether incorporating carboxymethyl chitosan (CMCS) in MTX-PMMA cement might overcome disadvantages associated with MTX. To determine the optimal CMCS+MTX concentration to suppress the viability of cancer cells, an integrated microfluidic chip culturing highly metastatic lung cancer cells (H460) was employed. The mechanical properties, microstructure, and MTX release of (CMCS+MTX)-PMMA cement were evaluated respectively by universal mechanical testing machine, scanning electron microscopy (SEM), and incubation in simulated body fluid with subsequent HPLC-MS. Implants of MTX-PMMA and (CMCS+MTX)-PMMA cement were evaluated in vivo in guinea pig femurs over time using spiral computed tomography with three-dimensional image reconstruction, and SEM at 6 months. Viability of H460 cells was significantly lowest after treatment with 57 μg/mL CMCS + 21 μg/mL MTX, which was thus used in subsequent experiments. Incorporation of 1.6% (w/w) CMCS to MTX-PMMA significantly increased the bending modulus, bending strength, and compressive strength by 5, 2.8, and 5.2%, respectively, confirmed by improved microstructural homogeneity. Incorporation of CMCS delayed the time-to-plateau of MTX release by 2 days, but increased the fraction released at the plateau from 3.24% (MTX-PMMA) to 5.34%. Relative to the controls, the (CMCS+MTX)-PMMA implants integrated better with the host bone. SEM revealed pores in the cement of the (CMCS+MTX)-PMMA implants that were not obvious in the controls. In conclusion, incorporation of CMCS in MTX-PMMA appears a feasible and effective modification for improving the anti-tumor properties of MTX-PMMA cement.

Regeneration of the periodontium using enamel matrix derivative in combination with an injectable bone cement.

PubMed

Oortgiesen, Daniël A W; Meijer, Gert J; Bronckers, Antonius L J J; Walboomers, X Frank; Jansen, John A

2013-03-01

Enamel matrix derivative (EMD) has proven to enhance periodontal regeneration; however, its effect is mainly restricted to the soft periodontal tissues. Therefore, to stimulate not only the soft tissues, but also the hard tissues, in this study EMD is combined with an injectable calcium phosphate cement (CaP; bone graft material). The aim was to evaluate histologically the healing of a macroporous CaP in combination with EMD. Intrabony, three-wall periodontal defects (2 × 2 × 1.7 mm) were created mesial of the first upper molar in 15 rats (30 defects). Defects were randomly treated according to one of the three following strategies: EMD, calcium phosphate cement and EMD, or left empty. The animals were killed after 12 weeks, and retrieved samples were processed for histology and histomorphometry. Empty defects showed a reparative type of healing without periodontal ligament or bone regeneration. As measured with on a histological grading scale for periodontal regeneration, the experimental groups (EMD and CaP/EMD) scored equally, both threefold higher compared with empty defects. However, most bone formation was measured in the CaP/EMD group; addition of CAP to EMD significantly enhanced bone formation with 50 % compared with EMD alone. Within the limits of this animal study, the adjunctive use of EMD in combination with an injectable cement, although it did not affect epithelial downgrowth, appeared to be a promising treatment modality for regeneration of bone and ligament tissues in the periodontium. The adjunctive use of EMD in combination with an injectable cement appears to be a promising treatment modality for regeneration of the bone and ligament tissues in the periodontium.

HA and double-layer HA-P2O5/CaO glass coatings: influence of chemical composition on human bone marrow cells osteoblastic behavior.

PubMed

Ferraz, M P; Fernandes, M H; Santos, J D; Monteiro, F J

2001-07-01

Human osteoblastic bone marrow derived cells were cultured for 28 days onto the surface of a glass reinforced hydroxyapatite (HA) composite and a commercial type HA plasma sprayed coatings, both in the "as-received" condition and after an immersion treatment with culture medium during 21 days. Cell proliferation and differentiation were analyzed as a function of the chemical composition of the coatings and the immersion treatment. Cell attachment, growth and differentiation of osteoblastic bone marrow cells seeded onto "as-received" plasma sprayed coatings were strongly affected by the time-dependent variation of the surface structure occurring during the first hours of culture. Initial interactions leading to higher amounts of adsorbed protein and zeta potential shifts towards negative charges appeared to result in surface structures with better biological performance. Cultures grown onto the pretreated coatings showed higher rate of cell proliferation and increased functional activity, as compared to those grown onto the corresponding "as-received" materials. However, the cell behavior was similar in the glass composite and HA coatings. The results showed that the glass composites present better characteristics for bone cell growth and function than HA. In addition, this work also provide evidence that the biological performance of the glass composites can be modulated and improved by manipulations in the chemical composition, namely in the content of glass added to HA. Copyright 2001 Kluwer Academic Publishers

An in vivo evaluation of PLLA/PLLA-gHA nano-composite for internal fixation of mandibular bone fractures.

PubMed

Peng, Weihai; Zheng, Wei; Shi, Kai; Wang, Wangshu; Shao, Ying; Zhang, Duo

2015-11-09

Internal fixation of bone fractures using biodegradable poly(L-lactic-acid) (PLLA)-based materials has attracted the attention of many researchers. In the present study, 36 male beagle dogs were randomly assigned to two groups: PLLA/PLLA-gHA (PLLA-grafted hydroxyapatite) group and PLLA group. PLLA/PLLA-gHA and PLLA plates were embedded in the muscular bags of the erector spinae and also implanted to fix mandibular bone fractures in respective groups. At 1, 2, 3, 6, 9, and 12 months postoperatively, the PLLA/PLLA-gHA and PLLA plates were evaluated by adsorption and degradation tests, and the mandibles were examined through radiographic analysis, biomechanical testing, and histological analysis. The PLLA/PLLA-gHA plates were non-transparent and showed a creamy white color, and the PLLA plates were transparent and faint yellow in color. At all time points following surgery, adsorption and degradation of the PLLA/PLLA-gHA plates were significantly less than those of the PLLA plates, and the lateral and longitudinal bending strengths of the surgically treated mandibles of the beagle dogs in the PLLA/PLLA-gHA group were significantly greater than those of the PLLA group and reached almost the value of intact mandibles at 12 months postoperatively. Additionally, relatively rapid bone healing was observed in the PLLA/PLLA-gHA group with the formation of new lamellar bone tissues at 12 months after the surgery. The PLLA/PLLA-gHA nano-composite can be employed as a biodegradable material for internal fixation of mandibular bone fractures.

Sacroplasty procedural extravasation with high viscosity bone cement: comparing the intraoperative long-axis versus short-axis techniques in osteoporotic cadavers.

PubMed

Miller, Jeffrey W; Diani, Art; Docsa, Steve; Ashton, Kristi; Sciamanna, Michele

2017-09-01

Percutaneous sacroplasty involves image-guided injection of bone cement for sacral insufficiency fractures to alleviate pain and facilitate mobility. Correct sacral placement of the cement and the risk of cement extravasation present procedural challenges. This study compares the occurrence, number, location, and surface area of high viscosity radiopaque bone cement extravasation via biplane fluoroscopy with Dyna CT between the fluoroscopically-guided intraoperative long-axis and short-axis sacroplasty techniques in osteoporotic cadavers. Ten osteoporotic cadavers underwent bilateral percutaneous instillation of VertaPlex HV High Viscosity Radiopaque Bone Cement. Long- and short-axis sacroplasty techniques were randomly assigned to zone 1 of the left or right sacral ala of each cadaver. Cement extravasation data were summarized by technique (long-axis vs short-axis) and time period (15-min and 3-hour post-procedure syngo DynaCT scan) in the form of point and CI estimates for the true proportions of cement extravasation. No procedural sacral extravasation differences were observed between the long-axis and short-axis sacroplasty techniques. There were no occurrences of intra-procedural or post-procedural cement extravasation at 15 min or 3 hours in association with either the long-axis sacroplasty technique or the short-axis sacroplasty technique. The long- and short-axis sacroplasty techniques, using high viscosity cement with careful post-procedural positioning, result in no occurrence of cement extravasation in porous osteoporotic cadaver bone. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Compression and flexural strength of bone cement mixed with blood.

PubMed

Tan, J H; Koh, B Th; Ramruttun, A K; Wang, W

2016-08-01

To assess the compression and flexural strength of bone cement mixed with 0 ml, 1 ml, or 2 ml of blood. High viscosity polymethyl methacrylate (PMMA) loaded with or without gentamicin was used. Blood was collected from total knee arthroplasty patients. In the same operating room, one pack of cement each was mixed with 0 ml (control), 1 ml, or 2 ml of blood for 1 minute during the dough phase. The dough was extruded into cylindrical and rectangular moulds for 20 minutes of setting, and then cured in phosphate buffered saline at 37±1ºC for 7 days. The samples were visually inspected for fractures and areas of weakness, and then scanned using microcomputed tomography. 48 gentamicin-loaded and 59 non-gentamicin-loaded samples mixed with 0 ml (control), 1 ml, or 2 ml of blood were randomised for flexural and compression strength testing; each group had at least 6 samples. In samples loaded with or without gentamicin, the flexural and compressive strength was highest in controls, followed by samples mixed with 1 ml or 2 ml of blood. In samples mixed with 2 ml of blood, the flexural strength fell below the standard of 50 MPa. In samples mixed with 2 ml of blood and all gentamicin-loaded samples, the compressive strength fell below the standard of 70 MPa. Microcomputed tomography revealed areas of voids and pores indicating the presence of laminations and partitions within. The biomechanical strength of PMMA contaminated with blood may decrease. Precautions such as saline lavage, pack drying the bone, change of gloves, and prompt insertion of the implant should be taken to prevent blood from contaminating bone cement.

A cemented cup with acetabular impaction bone grafting is more cost-effective than an uncemented cup in patients under 50 years.

PubMed

Busch, Vincent J J F; Verschueren, Joost; Adang, Eddy M; Lie, Stein A; Havelin, Leif I; Schreurs, Berend W

2016-01-01

Acetabular deficiencies in young patients can be restored in several ways during total hip arthroplasty. Currently, cementless cups are most frequently used. Impaction bone grafting of acetabular defects is a more biological approach, but is it cost-effective in young patients on the long term? We designed a decision model for a cost-utility analysis of a cemented cup with acetabular impaction bone grafting versus an uncemented cup, in terms of cost per quality-adjusted life year (QALY) for the young adult with acetabular bone deficiency, in need for a primary total hip arthroplasty. Outcome probabilities and effectiveness were derived from the Radboud University Nijmegen Medical Centre and the Norwegian Hip Register. Multiple sensitivity analyses were used to assess the contribution of the included variables in the model's outcome. Cemented cups with impaction bone grafting were more cost-effective compared to the uncemented option in terms of costs per QALY. A scenario suggesting equal primary survival rates of both cemented and uncemented cups still showed an effect gain of the cemented cup with impaction bone grafting, but at higher costs. Based on this model, the first choice of treatment of the acetabular bone deficient osteoarthritic hip in a young patient is reconstruction with impaction bone grafting and a cemented cup.

ALP gene expression in cDNA samples from bone tissue engineering using a HA/TCP/Chitosan scaffold

NASA Astrophysics Data System (ADS)

Stephanie, N.; Katarina, H.; Amir, L. R.; Gunawan, H. A.

2017-08-01

This study examined the potential use of hydroxyapatite (HA)/tricalcium phosphate (TCP)/Chitosan as a bone tissue engineering scaffold. The potential for using HA/TCP/chitosan as a scaffold was analyzed by measuring expression of the ALP osteogenic gene in cDNA from bone biopsies from four Macaque nemestrina. Experimental conditions included control (untreated), treatment with HA/TCP 70:30, HA/TCP 50:50, and HA/TCP/chitosan. cDNA samples were measured quantitively with Real-Time PCR (qPCR) and semi-quantitively by gel electrophoresis. There were no significant differences in ALP gene expression between treatment subjects after two weeks, but the HA/TCP/chitosan treatment gave the highest level of expression after four weeks. The scaffold using the HA/TCP/chitosan combination induced a higher level of expression of the osteogenic gene ALP than did scaffold without chitosan.

Effect of pulsed ultrasound in combination with gentamicin on bacterial killing of biofilms on bone cements in vivo

PubMed Central

Ensing, G.T.; Roeder, B.L.; Nelson, J.L.; van Horn, J.R.; van der Mei, H.C.; Busscher, H.J.; Pitt, W.G.

2008-01-01

Aim The aim of this study is to investigate whether pulsed ultrasound in combination with gentamicin yields increased killing of bacterial biofilms on bone cements in vivo. Methods and Results Bacterial survival on bone cement in the presence and absence of ultrasound was compared in a rabbit model. Two bone cement samples with E. coli ATCC 10798 biofilm were implanted in a total of nine rabbits. In two groups bone cement disks loaded with gentamicin were used, and in one group unloaded bone cement disks in combination with systemically administered gentamicin were used. Pulsed ultrasound with a mean acoustic intensity of 167 mW cm−2 and a maximum acoustic intensity of 500 mW cm−2 was applied from 24 h till 72 h post surgery on one of the two implanted disks. After euthanization, the bacteria removed from the disk were quantified. Application of ultrasound, combined with gentamicin, reduced the biofilm in all three groups varying between 58 to 69% compared to the negative control. Ultrasound proved to be safe with respect to creating skin lesions. Conclusions Ultrasound resulted in an tendency of improved efficacy of gentamicin, either applied locally or systemically. Significance and impact of Study This study implies that ultrasound could improve the prevention of infection, especially because the biomaterials, gentamicin and ultrasound used in this model are all in clinical usage, but not yet combined in clinical practice. PMID:16108785

HDAC inhibitor-loaded bone cement for advanced local treatment of osteosarcoma and chondrosarcoma.

PubMed

Tonak, Marcus; Becker, Marc; Graf, Claudine; Eckhard, Lukas; Theobald, Matthias; Rommens, Pol-Maria; Wehler, Thomas C; Proschek, Dirk

2014-11-01

The treatment of osteosarcoma, especially wide resection, is challenging. An additional local drug therapy after resection using anti-neoplastic bone cement (Polymethylmethacrylate (PMMA)) could help improve the outcome of therapy. In this study, we evaluated the effects of PMMA loaded with valproic acid (VPA) and suberoylanilide hydroxamic acid (SAHA) on the cell activity of a SaOs-2 cell culture, as well as the elution rate of the drugs out of the bone cement. In our experiments, we used the SaOs-2 osteosarcoma and the SW1353 chondrosarcoma cell line. Bone cement clots (5 g) were prepared and loaded with different drug concentrations of VPA (25 mg and 50 mg) and SAHA (1 mg, 2.5 mg and 5 mg). Two control groups were established, one with a native cement clot, the other with human mesenchymal stem cells, in order to evaluate toxicity on non tumor-cells. Cell activity was measured using an Alamar Blue assay on days 1, 2, 3, 4 and 7. The cement clots were additionally examined in a material testing unit for biomechanical and structural changes. Tumor cells showed a significant and complete reduction of activity under therapy with VPA and SAHA. Drug release of VPA was extensive between days 0 and 3 and decreased progressively to day 7. Cumulative drug concentration in the medium continuously increased. Biomechanical testing of the cement clots showed no differences in stability and architecture compared to the control group. SaOs-2 and SW1353 cells with medium from native cement clots without drug therapy presented a cell activity of 100% in all groups and during all measurements. Human mesenchymal stem cells were not significantly affected during therapy with VPA and low concentrations of SAHA. In contrast, cell activity of human mesenchymal stem cells was significantly reduced under therapy with higher concentrations of SAHA, with an approximately linear decrease between days 0-3 and a rapidly decreasing activity between days 4-7. A local cytotoxic therapy in the

Development and Characterization of Biphasic Hydroxyapatite/β-TCP Cements

PubMed Central

Gallinetti, Sara; Canal, Cristina; Ginebra, Maria-Pau; Ferreira, J

2014-01-01

Biphasic calcium phosphate bioceramics composed of hydroxyapatite (HA) and β-tricalcium phosphate (β-TCP) have relevant properties as synthetic bone grafts, such as tunable resorption, bioactivity, and intrinsic osteoinduction. However, they have some limitations associated to their condition of high-temperature ceramics. In this work self-setting Biphasic Calcium Phosphate Cements (BCPCs) with different HA/β-TCP ratios were obtained from self-setting α-TCP/β-TCP pastes. The strategy used allowed synthesizing BCPCs with modulated composition, compressive strength, and specific surface area. Due to its higher solubility, α-TCP was fully hydrolyzed to a calcium-deficient HA (CDHA), whereas β-TCP remained unreacted and completely embedded in the CDHA matrix. Increasing amounts of the non-reacting β-TCP phase resulted in a linear decrease of the compressive strength, in association to the decreasing amount of precipitated HA crystals, which are responsible for the mechanical consolidation of apatitic cements. Ca2+ release and degradation in acidic medium was similar in all the BCPCs within the timeframe studied, although differences might be expected in longer term studies once β-TCP, the more soluble phase was exposed to the surrounding media. PMID:25866411

Development and Characterization of Biphasic Hydroxyapatite/β-TCP Cements.

PubMed

Gallinetti, Sara; Canal, Cristina; Ginebra, Maria-Pau; Ferreira, J

2014-04-01

Biphasic calcium phosphate bioceramics composed of hydroxyapatite (HA) and β-tricalcium phosphate (β-TCP) have relevant properties as synthetic bone grafts, such as tunable resorption, bioactivity, and intrinsic osteoinduction. However, they have some limitations associated to their condition of high-temperature ceramics. In this work self-setting Biphasic Calcium Phosphate Cements (BCPCs) with different HA/β-TCP ratios were obtained from self-setting α-TCP/β-TCP pastes. The strategy used allowed synthesizing BCPCs with modulated composition, compressive strength, and specific surface area. Due to its higher solubility, α-TCP was fully hydrolyzed to a calcium-deficient HA (CDHA), whereas β-TCP remained unreacted and completely embedded in the CDHA matrix. Increasing amounts of the non-reacting β-TCP phase resulted in a linear decrease of the compressive strength, in association to the decreasing amount of precipitated HA crystals, which are responsible for the mechanical consolidation of apatitic cements. Ca 2+ release and degradation in acidic medium was similar in all the BCPCs within the timeframe studied, although differences might be expected in longer term studies once β-TCP, the more soluble phase was exposed to the surrounding media.

Hydroxyapatite clay for gap filling and adequate bone ingrowth.

PubMed

Maruyama, M; Terayama, K; Ito, M; Takei, T; Kitagawa, E

1995-03-01

In uncemented total hip arthroplasty, a complete filling of the gap between femoral prosthesis and the host bone is difficult and defects would remain, because the anatomy of the reamed intramedullary canal cannot fit the prosthesis. Therefore, it seems practical to fill the gap with a clay containing hydroxyapatite (HA), which has an osteoconductive character. The clay (HA clay) is made by mixing HA granules (size 0.1 mm or more) having a homogeneous pore distribution and a porosity of 35-48 vol%, and a viscous substance such as a saline solution of sodium alginate (SSSA). In the first experiment, the ratio of HA granules and sodium alginate in SSSA is set for the same handling properties of HA clay and polymethylmethacrylate bone cement (standard viscosity) before hardening. As a result, the ratio is set for 55 wt% of HA in the clay and 12.5 wt% of sodium alginate in SSSA (i.e., HA:sodium alginate:saline solution = 9.8:1:7). In the second study, the gap between the femoral stem and bone model is completely filled with HA clay. However, the gap is not filled only with HA granules or HA granules mixed with saline solution. In the third animal experiment, using an unloaded model, histology shows that HA clay has an osteoconductive property bridging the gap between the implant and the cortical bone without any adverse reaction. HA clay is considered a useful biomaterial to fill the gap with adequate bone ingrowth.

Monitoring of hardening and hygroscopic induced strains in a calcium phosphate bone cement using FBG sensor.

PubMed

Bimis, A; Karalekas, D; Bouropoulos, N; Mouzakis, D; Zaoutsos, S

2016-07-01

This study initially deals with the investigation of the induced strains during hardening stage of a self-setting calcium phosphate bone cement using fiber-Bragg grating (FBG) optical sensors. A complementary Scanning Electron Microscopy (SEM) investigation was also conducted at different time intervals of the hardening period and its findings were related to the FBG recordings. From the obtained results, it is demonstrated that the FBG response is affected by the microstructural changes taking place when the bone cement is immersed into the hardening liquid media. Subsequently, the FBG sensor was used to monitor the absorption process and hygroscopic response of the hardened and dried biocement when exposed to a liquid/humid environment. From the FBG-based calculated hygric strains as a function of moisture concentration, the coefficient of moisture expansion (CME) of the examined bone cement was obtained, exhibiting two distinct linear regions. Copyright © 2016 Elsevier Ltd. All rights reserved.

Gentamicin release from commercially-available gentamicin-loaded PMMA bone cements in a prosthesis-related interfacial gap model and their antibacterial efficacy.

PubMed

Neut, Daniëlle; Kluin, Otto S; Thompson, Jonathan; van der Mei, Henny C; Busscher, Henk J

2010-11-10

Around about 1970, a gentamicin-loaded poly (methylmethacrylate) (PMMA) bone cement brand (Refobacin Palacos R) was introduced to control infection in joint arthroplasties. In 2005, this brand was replaced by two gentamicin-loaded follow-up brands, Refobacin Bone Cement R and Palacos R + G. In addition, another gentamicin-loaded cement brand, SmartSet GHV, was introduced in Europe in 2003. In the present study, we investigated differences in gentamicin release and the antibacterial efficacy of the eluent between these four cement brands. 200 μm-wide gaps were made in samples of each cement and filled with buffer in order to measure the gentamicin release. Release kinetics were related to bone cement powder particle characteristics and wettabilities of the cement surfaces. Gaps were also inoculated with bacteria isolated from infected prostheses for 24 h and their survival determined. Gentamicin release and bacterial survival were statistically analysed using the Student's t-test. All three Palacos variants showed equal burst releases but each of the successor Palacos cements showed significantly higher sustained releases. SmartSet GHV showed a significantly higher burst release, while its sustained release was comparable with original Palacos. A gentamicin-sensitive bacterium did not survive in the high gentamicin concentrations in the interfacial gaps, while a gentamicin-resistant strain did, regardless of the type of cement used. Survival was independent of the level of burst release by the bone cement. Although marketed as the original gentamicin-loaded Palacos cement, orthopaedic surgeons should be aware that the successor cements do not appear to have the same release characteristics as the original one. Overall, high gentamicin concentrations were reached inside our prosthesis-related interfacial gap model. These concentrations may be expected to effectively decontaminate the prosthesis-related interfacial gap directly after implantation, provided that these

Effect of pulsed ultrasound in combination with gentamicin on bacterial viability in biofilms on bone cements in vivo.

PubMed

Ensing, G T; Roeder, B L; Nelson, J L; van Horn, J R; van der Mei, H C; Busscher, H J; Pitt, W G

2005-01-01

The aim of this study is to investigate whether pulsed ultrasound (US) in combination with gentamicin yields a decreased viability of bacteria in biofilms on bone cements in vivo. Bacterial survival on bone cement in the presence and absence of ultrasound was compared in a rabbit model. Two bone cement samples with an Escherichia coli ATCC 10798 biofilm were implanted in a total of nine rabbits. In two groups bone cement discs loaded with gentamicin, freshly prepared and aged were used, and in one group unloaded bone cement discs in combination with systemically administered gentamicin. Pulsed ultrasound with a frequency of 28.48 kHz and a maximum acoustic intensity of 500 mW cm(-2) was applied continuously from 24 h till 72 h postsurgery on one of the two implanted discs. After euthanization and removal of the bacteria from the discs, the number of viable bacteria were quantified and skin samples were analysed for histopathological examination. Application of ultrasound, combined with gentamicin, reduced the viability of the biofilms in all three groups varying between 58 and 69% compared with the negative control. Histopathological examinations showed no skin lesions. Ultrasound resulted in a tendency of improved efficacy of gentamicin, either applied locally or systemically. Usage of ultrasound in this model proved to be safe. This study implies that ultrasound could improve the prevention of infection immediately after surgery, especially because the biomaterials, gentamicin and ultrasound used in this model are all in clinical usage, but not yet combined in clinical practice.

High proximal migration in cemented acetabular revisions operated with bone impaction grafting; 47 revision cups followed with RSA for 17 years.

PubMed

Mohaddes, Maziar; Herberts, Peter; Malchau, Henrik; Johanson, Per-Erik; Kärrholm, Johan

2017-05-12

Bone impaction grafting is a biologically and mechanically appealing option in acetabular revision surgery, allowing restitution of the bone stock and restoration of the biomechanics. We analysed differences in proximal migration of the revision acetabular components when bone impaction grafting is used together with a cemented or an uncemented cup. 43 patients (47 hips), revised due to acetabular loosening and judged to have less than 50% host bone-implant contact were included. The hips were randomised to either an uncemented (n = 20) or a cemented (n = 27) revision cup. Radiostereometry and radiography was performed postoperatively, at 3 and 6 months, 1, 2, 3, 5, 7, 10 and 13 and 17 years postoperatively. Clinical follow-up was performed at 1, 2 and 5 years postoperatively and thereafter at the same interval as in the radiographic follow-up. There were no differences in the base line demographic data between the 2 groups. At the last follow-up (17 years) 14 hips (10 cemented, 4 uncemented) had been re-revised due to loosening. 3 additional cups (1 uncemented and 2 cemented) were radiographically loose. There was a higher early proximal migration in the cemented cups. Cups operated on with cement showed a higher early migration measured with RSA and also a higher number of late revisions. The reason for this is not known, but factors such as inclusion of cases with severe bone defects, use of smaller bone chips and issues related to the impaction technique might have had various degrees of influence.

Preparation of in situ hardening composite microcarriers: Calcium phosphate cement combined with alginate for bone regeneration

PubMed Central

Park, Jung-Hui; Lee, Eun-Jung; Knowles, Jonathan C

2014-01-01

Novel microcarriers consisting of calcium phosphate cement and alginate were prepared for use as three-dimensional scaffolds for the culture and expansion of cells that are effective for bone tissue engineering. The calcium phosphate cement-alginate composite microcarriers were produced by an emulsification of the composite aqueous solutions mixed at varying ratios (calcium phosphate cement powder/alginate solution = 0.8–1.2) in an oil bath and the subsequent in situ hardening of the compositions during spherodization. Moreover, a porous structure could be easily created in the solid microcarriers by soaking the produced microcarriers in water and a subsequent freeze-drying process. Bone mineral-like apatite nanocrystallites were shown to rapidly develop on the calcium phosphate cement–alginate microcarriers under moist conditions due to the conversion of the α-tricalcium phosphate phase in the calcium phosphate cement into a carbonate–hydroxyapatite. Osteoblastic cells cultured on the microspherical scaffolds were proven to be viable, with an active proliferative potential during 14 days of culture, and their osteogenic differentiation was confirmed by the determination of alkaline phosphatase activity. The in situ hardening calcium phosphate cement–alginate microcarriers developed herein may be used as potential three-dimensional scaffolds for cell delivery and tissue engineering of bone. PMID:23836845

Influence of semipermanent cement application used in immediately loaded, implant-supported restorations on crestal bone resorption.

PubMed

Błaszczyszyn, Artur; Kubasiewicz-Ross, Paweł; Gedrange, Tomasz; Dominiak, Marzena

2013-01-01

The paper presents clinical-radiological research on the impact of the new semi-cement luting agent in the immediately loaded implant-supported restoration on alveolar ridge resorption. 25 patients with a partially edentulous alveolar ridge in the anterior section of the maxilla or mandible were included in the study. The implants were inserted with the application of traditional burs or with a Piezosurgery device supplied by Mectron. Taking into account the method of implant bed preparation, the scientific material was divided into two groups. The implants were loaded immediately with single crown restorations cemented with the Implantlink semi cement application. The following indices were taken into consideration: pocket depth around implant calculated at four measuring points, marginal alveolar bone loss measured using radio-visiography, the 3-degree Wachtel scale of healing of the soft tissue. In addition, the presence and possible width or height of any recession around the implants was measured. The success of the implant treatment was assessed according to the Albrektsson success criteria. The research results were subjected to statistical analysis. The results of our study revealed no influence of the Implant-link semi cement on the crestal bone level, regardless of the bone bed preparation technique.

Optimization of a biomimetic bone cement: role of DCPD.

PubMed

Panzavolta, Silvia; Bracci, Barbara; Rubini, Katia; Bigi, Adriana

2011-08-01

We previously proposed a biomimetic α-tricalcium phosphate (α-TCP) bone cement where gelatin controls the transformation of α-TCP into calcium deficient hydroxyapatite (CDHA), leading to improved mechanical properties. In this study we investigated the setting and hardening processes of biomimetic cements containing increasing amounts of CaHPO(4)·2H2O (DCPD) (0, 2.5, 5, 10, 15 wt.%), with the aim to optimize composition. Both initial and final setting times increased significantly when DCPD content accounts for 10 wt.%, whereas cements containing 15 wt.% DCPD did not set at all. Differential scanning calorimetry (DSC), X-ray diffraction (XRD), thermogravimetry (TG) and scanning electron microscopy (SEM) investigations were performed on samples maintained in physiological solution for different times. DCPD dissolution starts soon after cement preparation, but the rate of transformation decreases on increasing DCPD initial content in the samples. The rate of α-TCP to CDHA conversion during hardening decreases on increasing DCPD initial content. Moreover, the presence of DCPD prevents gelatin release during hardening. The combined effects of gelatin and DCPD on the rate of CDHA formation and porosity lead to significantly improved mechanical properties, with the best composition displaying a compressive strength of 35 MPa and a Young modulus of 1600 MPa. Copyright © 2011 Elsevier Inc. All rights reserved.

Potential risks of using cement-augmented screws for spinal fusion in patients with low bone quality.

PubMed

Martín-Fernández, M; López-Herradón, A; Piñera, A R; Tomé-Bermejo, F; Duart, J M; Vlad, M D; Rodríguez-Arguisjuela, M G; Alvarez-Galovich, L

2017-08-01

Dramatic increases in the average life expectancy have led to increases in the variety of degenerative changes and deformities observed in the aging spine. The elderly population can present challenges for spine surgeons, not only because of increased comorbidities, but also because of the quality of their bones. Pedicle screws are the implants used most commonly in spinal surgery for fixation, but their efficacy depends directly on bone quality. Although polymethyl methacrylate (PMMA)-augmented screws represent an alternative for patients with osteoporotic vertebrae, their use has raised some concerns because of the possible association between cement leakages (CLs) and other morbidities. To analyze potential complications related to the use of cement-augmented screws for spinal fusion and to investigate the effectiveness of using these screws in the treatment of patients with low bone quality. A retrospective single-center study. This study included 313 consecutive patients who underwent spinal fusion using a total of 1,780 cement-augmented screws. We analyzed potential complications related to the use of cement-augmented screws, including CL, vascular injury, infection, screw extraction problems, revision surgery, and instrument failure. There are no financial conflicts of interest to report. A total of 1,043 vertebrae were instrumented. Cement leakage was observed in 650 vertebrae (62.3%). There were no major clinical complications related to CL, but two patients (0.6%) had radicular pain related to CL at the S1 foramina. Of the 13 patients (4.1%) who developed deep infections requiring surgical debridement, two with chronic infections had possible spondylitis that required instrument removal. All patients responded well to antibiotic therapy. Revision surgery was performed in 56 patients (17.9%), most of whom had long construction. A total of 180 screws were removed as a result of revision. There were no problems with screw extraction. These results

Validation of a measuring technique with computed tomography for cement penetration into trabecular bone underneath the tibial tray in total knee arthroplasty on a cadaver model

PubMed Central

2014-01-01

Background In total knee arthroplasty (TKA), cement penetration between 3 and 5 mm beneath the tibial tray is required to prevent loosening of the tibia component. The objective of this study was to develop and validate a reliable in vivo measuring technique using CT imaging to assess cement distribution and penetration depth in the total area underneath a tibia prosthesis. Methods We defined the radiodensity ranges for trabecular tibia bone, polymethylmethacrylate (PMMA) cement and cement-penetrated trabecular bone and measured the percentages of cement penetration at various depths after cementing two tibia prostheses onto redundant femoral heads. One prosthesis was subsequently removed to examine the influence of the metal tibia prostheses on the quality of the CT images. The percentages of cement penetration in the CT slices were compared with percentages measured with photographs of the corresponding transversal slices. Results Trabecular bone and cement-penetrated trabecular bone had no overlap in quantitative scale of radio-density. There was no significant difference in mean HU values when measuring with or without the tibia prosthesis. The percentages of measured cement-penetrated trabecular bone in the CT slices of the specimen were within the range of percentages that could be expected based on the measurements with the photographs (p = 0.04). Conclusions CT scan images provide valid results in measuring the penetration and distribution of cement into trabecular bone underneath the tibia component of a TKA. Since the proposed method does not turn metal elements into artefacts, it enables clinicians to assess the width and density of the cement mantle in vivo and to compare the results of different cementing methods in TKA. PMID:25158996

Implant Augmentation: Adding Bone Cement to Improve the Treatment of Osteoporotic Distal Femur Fractures

PubMed Central

Wähnert, Dirk; Hofmann-Fliri, Ladina; Richards, R. Geoff; Gueorguiev, Boyko; Raschke, Michael J.; Windolf, Markus

2014-01-01

Abstract The increasing problems in the field of osteoporotic fracture fixation results in specialized implants as well as new operation methods, for example, implant augmentation with bone cement. The aim of this study was to determine the biomechanical impact of augmentation in the treatment of osteoporotic distal femur fractures. Seven pairs of osteoporotic fresh frozen distal femora were randomly assigned to either an augmented or nonaugmented group. In both groups, an Orthopaedic Trauma Association 33 A3 fractures was fixed using the locking compression plate distal femur and cannulated and perforated screws. In the augmented group, additionally, 1 mL of polymethylmethacrylate cement was injected through the screw. Prior to mechanical testing, bone mineral density (BMD) and local bone strength were determined. Mechanical testing was performed by cyclic axial loading (100 N to 750 N + 0.05N/cycle) using a servo-hydraulic testing machine. As a result, the BMD as well as the axial stiffness did not significantly differ between the groups. The number of cycles to failure was significantly higher in the augmented group with the BMD as a significant covariate. In conclusion, cement augmentation can significantly improve implant anchorage in plating of osteoporotic distal femur fractures. PMID:25415673

Audiometric evaluation of an attempt to optimize the fixation of the transducer of a middle-ear implant to the ossicular chain with bone cement.

PubMed

Snik, A; Cremers, C

2004-02-01

Typically, an implantable hearing device consists of a transducer that is coupled to the ossicular chain and electronics. The coupling is of major importance. The Vibrant Soundbridge (VSB) is such an implantable device; normally, the VSB transducer is fixed to the ossicular chain by means of a special clip that is crimped around the long process of the incus. In addition to crimping, bone cement was used to optimize the fixation in six patients. Long-term results were compared to those of five controls with crimp fixation alone. To assess the effect of bone cement (SerenoCem, Corinthian Medical Ltd, Nottingham, UK) on hearing thresholds, long-term post-surgery thresholds were compared to pre-surgery thresholds. Bone cement did not have any negative effect. Next, to test the hypothesis that aided thresholds might be better with the use of bone cement, aided thresholds were studied. After correction for the severity of hearing loss, only a small difference was found between the two groups at one frequency, viz. 2 kHz. It was concluded that there was no negative effect of using bone cement; however, there is also no reason to use bone cement in VSB users on a regular basis.

Biomedical potential of chitosan/HA and chitosan/β-1,3-glucan/HA biomaterials as scaffolds for bone regeneration--A comparative study.

PubMed

Przekora, Agata; Palka, Krzysztof; Ginalska, Grazyna

2016-01-01

The aim of this work was to compare biomedical potential of chitosan/hydroxyapatite (chit/HA) and novel chitosan/β-1,3-glucan/hydroxyapatite (chit/glu/HA) materials as scaffolds for bone regeneration via characterization of their biocompatibility, porosity, mechanical properties, and water uptake behaviour. Biocompatibility of the scaffolds was assessed in direct-contact with the materials using normal human foetal osteoblast cell line. Cytotoxicity and osteoblast proliferation rate were evaluated. Porosity was assessed using computed microtomography analysis and mechanical properties were determined by compression testing. Obtained results demonstrated that chit/HA scaffold possessed significantly better mechanical properties (compressive strength: 1.23 MPa, Young's modulus: 0.46 MPa) than chit/glu/HA material (compressive strength: 0.26 MPa, Young's modulus: 0.25 MPa). However, addition of bacterial β-1,3-glucan to the chit/HA scaffold improved its flexibility and porosity. Moreover, chit/glu/HA scaffold revealed significantly higher water uptake capability (52.6% after 24h of soaking) compared to the chit/HA (30.7%) and thus can serve as a very good drug delivery carrier. Chit/glu/HA scaffold was also more favourable to osteoblast survival (near 100% viability after 24-h culture), proliferation, and spreading compared to the chit/HA (63% viability). The chit/glu/HA possesses better biomedical potential than chit/HA scaffold. Nevertheless, poor mechanical properties of the chit/glu/HA limit its application to non-load bearing implantation area. Copyright © 2015 Elsevier B.V. All rights reserved.

Fatigue creep damage at the cement-bone interface: an experimental and a micro-mechanical finite element study

PubMed Central

Waanders, Daan; Janssen, Dennis; Miller, Mark A.; Mann, Kenneth A.; Verdonschot, Nico

2009-01-01

The goal of this study was to quantify the micromechanics of the cement-bone interface under tensile fatigue loading using finite element analysis (FEA) and to understand the underlying mechanisms that play a role in the fatigue behavior of this interface. Laboratory cement-bone specimens were subjected to a tensile fatigue load, while local displacements and crack growth on the specimen's surface were monitored. FEA models were created from these specimens based upon micro-computed tomography data. To accurately model interfacial gaps at the interface between the bone and cement, a custom-written erosion algorithm was applied to the bone model. A fatigue load was simulated in the FEA models while monitoring the local displacements and crack propagation. The results showed the FEA models were able to capture the general experimental creep damage behavior and creep stages of the interface. Consistent with the experiments, the majority of the deformation took place at the contact interface. Additionally, the FEA models predicted fatigue crack patterns similar to experimental findings. Experimental surface cracks correlated moderately with FEA surface cracks (r2=0.43), but did not correlate with the simulated crack volume fraction (r2=0.06). Although there was no relationship between experimental surface cracks and experimental creep damage displacement (r2=0.07), there was a strong relationship between the FEA crack volume fraction and the FEA creep damage displacement (r2=0.76). This study shows the additional value of FEA of the cement-bone interface relative to experimental studies and can therefore be used to optimize its mechanical properties. PMID:19682690

Hybrid Macro-Porous Titanium Ornamented by Degradable 3D Gel/nHA Micro-Scaffolds for Bone Tissue Regeneration

PubMed Central

Yin, Bo; Ma, Pei; Chen, Jun; Wang, Hai; Wu, Gui; Li, Bo; Li, Qiang; Huang, Zhifeng; Qiu, Guixing; Wu, Zhihong

2016-01-01

Porous titanium is a kind of promising material for bone substitution, while its bio-inert property results in demand of modifications to improve the osteointegration capacity. In this study, gelatin (Gel) and nano-hydroxyapatite (nHA) were used to construct 3D micro-scaffolds in the pores of porous titanium in the ratios of Gel:nHA = 1:0, Gel:nHA = 1:1, and Gel:nHA = 1:3, respectively. Cell attachment and proliferation, and gene and protein expression levels of osteogenic markers were evaluated in MC3T3-E1 cells, followed by bone regeneration assessment in a rabbit radius defect model. All hybrid scaffolds with different composition ratio were found to have significant promotional effects in cell adhesion, proliferation and differentiation, in which the group with Gel:nHA = 1:1 showed the best performance in vitro, as well as the most bone regeneration volume in vivo. This 3D micro-scaffolds modification may be an innovative method for porous titanium ornamentation and shows potential application values in clinic. PMID:27092492

Hybrid Macro-Porous Titanium Ornamented by Degradable 3D Gel/nHA Micro-Scaffolds for Bone Tissue Regeneration.

PubMed

Yin, Bo; Ma, Pei; Chen, Jun; Wang, Hai; Wu, Gui; Li, Bo; Li, Qiang; Huang, Zhifeng; Qiu, Guixing; Wu, Zhihong

2016-04-15

Porous titanium is a kind of promising material for bone substitution, while its bio-inert property results in demand of modifications to improve the osteointegration capacity. In this study, gelatin (Gel) and nano-hydroxyapatite (nHA) were used to construct 3D micro-scaffolds in the pores of porous titanium in the ratios of Gel:nHA = 1:0, Gel:nHA = 1:1, and Gel:nHA = 1:3, respectively. Cell attachment and proliferation, and gene and protein expression levels of osteogenic markers were evaluated in MC3T3-E1 cells, followed by bone regeneration assessment in a rabbit radius defect model. All hybrid scaffolds with different composition ratio were found to have significant promotional effects in cell adhesion, proliferation and differentiation, in which the group with Gel:nHA = 1:1 showed the best performance in vitro, as well as the most bone regeneration volume in vivo. This 3D micro-scaffolds modification may be an innovative method for porous titanium ornamentation and shows potential application values in clinic.

Facial skeletal augmentation using hydroxyapatite cement.

PubMed

Shindo, M L; Costantino, P D; Friedman, C D; Chow, L C

1993-02-01

This study investigates the use of a new calcium phosphate cement, which sets to solid, microporous hydroxyapatite, for facial bone augmentation. In six dogs, the supraorbital ridges were augmented bilaterally with this hydroxyapatite cement. On one side, the hydroxyapatite cement was placed directly onto the bone within a subperiosteal pocket. On the opposite side, the cement was contained within a collagen membrane tubule and then inserted into a subperiosteal pocket. The use of collagen tubules facilitated easy, precise placement of the cement. All implants maintained their original augmented height throughout the duration of the study. They were well tolerated without extrusion or migration, and there was no significant sustained inflammatory response. Histologic studies, performed at 3, 6, and 9 months revealed that when the cement was placed directly onto bone, progressive replacement of the implant by bone (osseointegration of the hydroxyapatite with the underlying bone) without a loss of volume was observed. In contrast, when the cement-collagen tubule combination was inserted, primarily a fibrous union was noted. Despite such fibrous union, the hydroxyapatite-collagen implant solidly bonded to the underlying bone, and no implant resorption was observed. Hydroxyapatite cement can be used successfully for the experimental augmentation of the craniofacial skeleton and may be applicable for such uses in humans.

Calcium phosphate cements for bone engineering and their biological properties

PubMed Central

Xu, Hockin HK; Wang, Ping; Wang, Lin; Bao, Chongyun; Chen, Qianming; Weir, Michael D; Chow, Laurence C; Zhao, Liang; Zhou, Xuedong; Reynolds, Mark A

2017-01-01

Calcium phosphate cements (CPCs) are frequently used to repair bone defects. Since their discovery in the 1980s, extensive research has been conducted to improve their properties, and emerging evidence supports their increased application in bone tissue engineering. Much effort has been made to enhance the biological performance of CPCs, including their biocompatibility, osteoconductivity, osteoinductivity, biodegradability, bioactivity, and interactions with cells. This review article focuses on the major recent developments in CPCs, including 3D printing, injectability, stem cell delivery, growth factor and drug delivery, and pre-vascularization of CPC scaffolds via co-culture and tri-culture techniques to enhance angiogenesis and osteogenesis. PMID:29354304

Peri-Implant Distribution of Polyethylene Debris in Postmortem-Retrieved Knee Arthroplasties: Can Polyethylene Debris Explain Loss of Cement-Bone Interlock in Successful Total Knee Arthroplasties?

PubMed

Cyndari, Karen I; Goodheart, Jacklyn R; Miller, Mark A; Oest, Megan E; Damron, Timothy A; Mann, Kenneth A

2017-07-01

Loss of mechanical interlock between cement and bone with in vivo service has been recently quantified for functioning, nonrevised, cemented total knee arthroplasties (TKAs). The cause of interlocking trabecular resorption is not known. The goal of this study is to quantify the distribution of PE debris at the cement-bone interface and determine if polyethylene (PE) debris is locally associated with loss of interlock. Fresh, nonrevised, postmortem-retrieved TKAs (n = 8) were obtained en bloc. Laboratory-prepared constructs (n = 2) served as negative controls. The intact cement-bone interface of each proximal tibia was embedded in Spurr's resin, sectioned, and imaged under polarized light to identify birefringent PE particles. PE wear particle number density was quantified at the cement-bone interface and distal to the interface, and then compared with local loss of cement-bone interlock. The average PE particle number density for postmortem-retrieved TKAs ranged from 8.6 (1.3) to 24.9 (3.1) particles/mm 2 (standard error) but was weakly correlated with years in service. The average particle number density was twice as high as distal (>5mm) to the interface compared to at the interface. The local loss of interlock at the interface was not related to the presence, absence, or particle density of PE. PE debris can migrate extensively along the cement-bone interface of well-fixed tibial components. However, the amount of local bone loss at the cement-bone interface was not correlated with the amount of PE debris at the interface, suggesting that the observed loss of trabecular interlock in these well-fixed TKAs may be due to alternative factors. Copyright © 2017 Elsevier Inc. All rights reserved.

Adhesive strength of total knee endoprostheses to bone cement - analysis of metallic and ceramic femoral components under worst-case conditions.

PubMed

Bergschmidt, Philipp; Dammer, Rebecca; Zietz, Carmen; Finze, Susanne; Mittelmeier, Wolfram; Bader, Rainer

2016-06-01

Evaluation of the adhesive strength of femoral components to the bone cement is a relevant parameter for predicting implant safety. In the present experimental study, three types of cemented femoral components (metallic, ceramic and silica/silane-layered ceramic) of the bicondylar Multigen Plus knee system, implanted on composite femora were analysed. A pull-off test with the femoral components was performed after different load and several cementing conditions (four groups and n=3 components of each metallic, ceramic and silica/silane-layered ceramic in each group). Pull-off forces were comparable for the metallic and the silica/silane-layered ceramic femoral components (mean 4769 N and 4298 N) under standard test condition, whereas uncoated ceramic femoral components showed reduced pull-off forces (mean 2322 N). Loading under worst-case conditions led to decreased adhesive strength by loosening of the interface implant and bone cement using uncoated metallic and ceramic femoral components, respectively. Silica/silane-coated ceramic components were stably fixed even under worst-case conditions. Loading under high flexion angles can induce interfacial tensile stress, which could promote early implant loosening. In conclusion, a silica/silane-coating layer on the femoral component increased their adhesive strength to bone cement. Thicker cement mantles (>2 mm) reduce adhesive strength of the femoral component and can increase the risk of cement break-off.

Treating osteoporotic vertebral compression fractures with intraosseous vacuum phenomena using high-viscosity bone cement via bilateral percutaneous vertebroplasty

PubMed Central

Guo, Dan; Cai, Jun; Zhang, Shengfei; Zhang, Liang; Feng, Xinmin

2017-01-01

Abstract Osteoporotic vertebral compression fractures with intraosseous vacuum phenomena could cause persistent back pains in patients, even after receiving conservative treatment. The aim of this study was to evaluate the efficacy of using high-viscosity bone cement via bilateral percutaneous vertebroplasty in treating patients who have osteoporotic vertebral compression fractures with intraosseous vacuum phenomena. Twenty osteoporotic vertebral compression fracture patients with intraosseous vacuum phenomena, who received at least 2 months of conservative treatment, were further treated by injecting high-viscosity bone cement via bilateral percutaneous vertebroplasty due to failure of conservative treatment. Treatment efficacy was evaluated by determining the anterior vertebral compression rates, visual analog scale (VAS) scores, and Oswestry disability index (ODI) scores at 1 day before the operation, on the first day of postoperation, at 1-month postoperation, and at 1-year postoperation. Three of 20 patients had asymptomatic bone cement leakage when treated via percutaneous vertebroplasty; however, no serious complications related to these treatments were observed during the 1-year follow-up period. A statistically significant improvement on the anterior vertebral compression rates, VAS scores, and ODI scores were achieved after percutaneous vertebroplasty. However, differences in the anterior vertebral compression rate, VAS score, and ODI score in the different time points during the 1-year follow-up period was not statistically significant (P > 0.05). Within the limitations of this study, the injection of high-viscosity bone cement via bilateral percutaneous vertebroplasty for patients who have osteoporotic vertebral compression fractures with intraosseous vacuum phenomena significantly relieved their back pains and improved their daily life activities shortly after the operation, thereby improving their life quality. In this study, the use of high

[Effect of bone cement application on the incidence of deep vein thrombosis in major joint arthroplasties].

PubMed

Aslan, Ahmet; Ağar, Emre; Aydoğan, Nevres Hürriyet; Atay, Tolga; Baydar, Metin Lütfi; Kırdemir, Vecihi; Ozden, Ahmet

2011-12-01

In this study, we have investigated whether the application of bone cement has an effect on the frequency of deep vein thrombosis (DVT) in major joint arthroplasties (MJA). A total of 95 MJA cases meeting the inclusion criteria of this study between January 2004 and January 2005 were divided into cemented and cementless groups. For prophylaxis, all patients were given low molecular weight heparin (LMWH). The patients were scanned for DVT preoperatively and on the postoperative 12(th) day by color Doppler ultrasonography. In hip arthroplasties, in knee arthroplasties and in general, DVT was seen more frequently in cemented group, however, there was no statistically significant difference between groups in the frequency of DVT (p=0.549, p=0.749 and p=0.462, respectively). Also, there was no significant difference between the results of the different LMWH groups (p=0.616). The results of this study shows that bone cement application in MJAs such as hip or knee arthroplasties has no significant effect on the frequency of DVT.

Bone cement: how effective is it at restoring hearing in isolated incudostapedial erosion?

PubMed

Watson, G J; Narayan, S

2014-08-01

To determine the effectiveness of biocements in rebridging isolated incudostapedial erosion. A review of the use of biocements for isolated incudostapedial joint erosion was performed on publications from 1998 to 2012 available from Medline, Embase and Pubmed. Inclusion criteria were papers published in English, case series or comparative studies with more than 10 patients, isolated incudostapedial erosion through chronic ear disease, minimal air-bone gap less than 20 dB (or air-bone gap less than 10 dB) and follow up for at least one year. In 108 patients, rebridging ossiculoplasty was performed using hydroxyapatite cement. Closure of air-bone gaps less than 20 dB and less than 10 dB was achieved in 80-94.4 per cent and 29-75 per cent, respectively. Glass ionomer cement was used in 318 patients. Closure of air-bone gaps less than 20 dB and less than 10 dB was achieved in 74-94 per cent and 40-76 per cent, respectively. Biocements can be successfully used to close isolated incudostapedial erosions. Larger comparative prospective studies documenting the length of eroded incus and types of reformation of the incudostapedial joint, with standardised reporting, are needed in the future.

A Novel Injectable Calcium Phosphate Cement-Bioactive Glass Composite for Bone Regeneration

PubMed Central

Zhao, Kang; Tang, Yufei; Cheng, Zhe; Chen, Jun; Zang, Yuan; Wu, Jianwei; Kong, Liang; Liu, Shuai; Lei, Wei; Wu, Zixiang

2013-01-01

Background Calcium phosphate cement (CPC) can be molded or injected to form a scaffold in situ, which intimately conforms to complex bone defects. Bioactive glass (BG) is known for its unique ability to bond to living bone and promote bone growth. However, it was not until recently that literature was available regarding CPC-BG applied as an injectable graft. In this paper, we reported a novel injectable CPC-BG composite with improved properties caused by the incorporation of BG into CPC. Materials and Methods The novel injectable bioactive cement was evaluated to determine its composition, microstructure, setting time, injectability, compressive strength and behavior in a simulated body fluid (SBF). The in vitro cellular responses of osteoblasts and in vivo tissue responses after the implantation of CPC-BG in femoral condyle defects of rabbits were also investigated. Results CPC-BG possessed a retarded setting time and markedly better injectability and mechanical properties than CPC. Moreover, a new Ca-deficient apatite layer was deposited on the composite surface after immersing immersion in SBF for 7 days. CPC-BG samples showed significantly improved degradability and bioactivity compared to CPC in simulated body fluid (SBF). In addition, the degrees of cell attachment, proliferation and differentiation on CPC-BG were higher than those on CPC. Macroscopic evaluation, histological evaluation, and micro-computed tomography (micro-CT) analysis showed that CPC-BG enhanced the efficiency of new bone formation in comparison with CPC. Conclusions A novel CPC-BG composite has been synthesized with improved properties exhibiting promising prospects for bone regeneration. PMID:23638115

How Long Does Antimycobacterial Antibiotic-loaded Bone Cement Have In Vitro Activity for Musculoskeletal Tuberculosis?

PubMed

Lee, Jae Hoo; Han, Chang Dong; Cho, Sang-Nae; Yang, Ick Hwan; Lee, Woo Suk; Baek, Seung-Hun; Shin, Jae Won; Husein, Khalid Elfadil Ibrahim; Park, Kwan Kyu

2017-11-01

Antibiotic-loaded bone cement is accepted as an effective treatment modality for musculoskeletal tuberculosis. However, comparative information regarding combinations and concentrations of second-line antimycobacterial drugs, such as streptomycin and amoxicillin and clavulanic acid, are lacking. (1) In antibiotic-loaded cement, is there effective elution of streptomycin and Augmentin ® (amoxicillin and clavulanic acid) individually and in combination? (2) What is the antibacterial activity duration for streptomycin- and amoxicillin and clavulanic acid -loaded cement? Six different types of bone cement discs were created by mixing 40 g bone cement with 1 or 2 g streptomycin only, 0.6 g or 1.2 g Augmentin ® (amoxicillin and clavulanic acid) only, and a combination of 1 g streptomycin plus 0.6 g amoxicillin and clavulanic acid and 2 g streptomycin plus 1.2 g amoxicillin and clavulanic acid. Five bone discs of each type were incubated in phosphate buffered saline for 30 days with renewal of the phosphate buffered saline every day. The quantity of streptomycin and/or amoxicillin and clavulanic acid in eluates were measured by a liquid chromatography-mass spectrometry system, and the antimycobacterial activity of eluates against Mycobacterium tuberculosis H37Rv, were calculated by comparing the minimal inhibitory concentration of each eluate with that of tested drugs using broth dilution assay on microplate. Streptomycin was detected in eluates for 30 days (in 1 g and 2 g discs), whereas 1.2 g amoxicillin and clavulanate eluted until Day 7 and 0.6 g amoxicillin and clavulanate until Day 3. All eluates in streptomycin-containing discs (streptomycin only, and in combination with amoxicillin and clavulanic acid) had effective antimycobacterial activity for 30 days, while amoxicillin and clavulanate-only preparations were only active until Day 14. The antimycobacterial activity of eluates of 2 g streptomycin plus 1.2 g amoxicillin and clavulanate were higher than those of

Development and characterization of an injectable cement of nano calcium-deficient hydroxyapatite/multi(amino acid) copolymer/calcium sulfate hemihydrate for bone repair

PubMed Central

Qi, Xiaotong; Li, Hong; Qiao, Bo; Li, Weichao; Hao, Xinyan; Wu, Jun; Su, Bao; Jiang, Dianming

2013-01-01

A novel injectable bone cement was developed by integration of nano calcium-deficient hydroxyapatite/multi(amino acid) copolymer (n-CDHA/MAC) and calcium sulfate hemihydrate (CSH; CaSO4 · 1/2H2O). The structure, setting time, and compressive strength of the cement were investigated. The results showed that the cement with a liquid to powder ratio of 0.8 mL/g exhibited good injectability and appropriate setting time and mechanical properties. In vitro cell studies indicated that MC3T3-E1 cells cultured on the n-CDHA/MAC/CSH composite spread well and showed a good proliferation state. The alkaline phosphatase activity of the MC3T3-E1 cells cultured on the n-CDHA/MAC/CSH composite was significantly higher than that of the cells on pure CSH at 4 and 7 days of culture. The n-CDHA/MAC/CSH cement was implanted into critical size defects of the femoral condyle in rabbits to evaluate its biocompatibility and osteogenesis in vivo. Radiological and histological results indicated that introduction of the n-CDHA/MAC into CSH enhanced new bone formation, and the n-CDHA/MAC/CSH cement exhibited good biocompatibility and degradability. In conclusion, the injectable n-CDHA/MAC/CSH composite cement has a significant clinical advantage over pure CSH cement, and may be a promising bone graft substitute for the treatment of bone defects. PMID:24293996

Cement lines of secondary osteons in human bone are not mineral-deficient: new data in a historical perspective.

PubMed

Skedros, John G; Holmes, Jennifer L; Vajda, Eric G; Bloebaum, Roy D

2005-09-01

Using qualitative backscattered electron (BSE) imaging and quantitative energy dispersive X-ray (EDX) spectroscopy, some investigators have concluded that cement (reversal) lines located at the periphery of secondary osteons are poorly mineralized viscous interfaces with respect to surrounding bone. This conclusion contradicts historical observations of apparent highly mineralized (or collagen-deficient) cement lines in microradiographs. Such conclusions, however, may stem from unrecognized artifacts that can occur during scanning electron microscopy. These include specimen degradation due to high-energy beams and the sampling of electron interaction volumes that extend beyond target locations during EDX analysis. This study used quantitative BSE imaging and EDX analysis, each with relatively lower-energy beams, to test the hypothesis that cement lines are poorly mineralized. Undemineralized adult human femoral diaphyses (n = 8) and radial diaphyses (n = 5) were sectioned transversely, embedded in polymethyl methacrylate, and imaged in a scanning electron microscope for BSE and EDX analyses. Unembedded samples were also evaluated. Additional thin embedded samples were stained and evaluated with light microscopy and correlated BSE imaging. BSE analyses showed the consistent presence of a bright line (higher atomic number) coincident with the classical location and description of the cement line. This may represent relative hypermineralization or, alternatively, collagen deficiency with respect to surrounding bone. EDX analyses of cement lines showed either higher Ca content or equivalent Ca content when compared to distant osteonal and interstitial bone. These data reject the hypothesis that cement lines of secondary osteons are poorly mineralized. Copyright 2005 Wiley-Liss, Inc

A comparative study on sealing ability of mineral trioxide aggregate, calcium enriched cement and bone cement in furcal perforations.

PubMed

Nazari Moghadam, K; Aghili, H; Rashed Mohassel, A; Zahedpasha, S; Moghadamnia, A A

2014-06-01

The aim of this study was to compare the bacterial leakage of mineral trioxide aggregate (MTA), calcium enriched cement (CEM), and bone cement (BC) as repair materials in furcal perforations. The pulp chambers of 57 human mandibular molar teeth were accessed and the root canal orifices were located. The roots were horizontally sectioned in the middle third. Composite resin was used to fill the root canal orifices and the apical end of the roots. The 1 mm furcation perforations were performed in the center of the pulp chamber floor, using diamond fissure burs. Fifty one teeth were divided into 3 groups. Six teeth were used as controls. Perforation defects were repaired with either MTA, CEM, or BC. A bacterial leakage model utilizing phenol red with 3% lactose broth was used for evaluation. The upper pulp chambers were subsequently filled with 5μL bacterial suspension containing Enterococcus faecalis. Then the top of the assembly was covered with aluminum foil to avoid unintentional contamination. The entire apparatus was incubated at 37°C, and bacterial leakage was evaluated daily by checking the turbidity in the culture medium of the lower part of the chamber. The bacterial inoculation was renewed every day, for 30 days. Leakage was noted when color conversion of the culture media was observed and was statistically analyzed using the Chi-square test with significance set at P< 0.05. Sixteen (94%) of the 17 samples of the MTA group, thirteen (81%) of the 17 samples of the CEM group and sixteen (94%) of the 17 samples in BC group were fully contaminated at 30 days. There was no statistically significant difference between the three study groups (P>0.05). According to the present study, in teeth with furcation perforations, the coronal seal produced by MTA preparations was equally to that produced by CEM cement and Bone cement.

Clinical and histologic evaluation of calcium-phosphate bone cement in interproximal osseous defects in humans: a report in four patients.

PubMed

Mellonig, James T; Valderrama, Pilar; Cochran, David L

2010-04-01

This study evaluated the clinical and histologic results of a calcium phosphate bone cement in the treatment of human periodontal intraosseous defects. Four patients with chronic advanced periodontitis in whom treatment with complete dentures was planned were recruited. The cement was implanted in one defect per subject with a presurgical probing depth of at least 7 mm and a radiographic bone defect of 4 mm or more. Patients were seen every 2 weeks for periodontal maintenance. At 6 months, clinical measurements were repeated and the tooth was removed en bloc for histologic processing. Results demonstrated that all defects resulted in probing depth reduction and, at three of the four defects, in clinical attachment level gain. However, no site showed periodontal regeneration. There was no new bone formation. New cementum and connective tissue were limited to 0.2 mm or less. Large deposits of the bone cement were noted encapsulated in connective tissue.

Incorporation of fast dissolving glucose porogens into an injectable calcium phosphate cement for bone tissue engineering.

PubMed

Smith, Brandon T; Santoro, Marco; Grosfeld, Eline C; Shah, Sarita R; van den Beucken, Jeroen J J P; Jansen, John A; Mikos, Antonios G

2017-03-01

Calcium phosphate cements (CPCs) have been extensively investigated as scaffolds in bone tissue engineering in light of their chemical composition closely resembling the mineral component of bone extracellular matrix. Yet, the degradation kinetics of many CPCs is slow compared to de novo bone formation. In order to overcome this shortcoming, the use of porogens within CPCs has been suggested as a potential strategy to increase scaffold porosity and promote surface degradation. This study explored the usage of glucose microparticles (GMPs) as porogens for the introduction of macroporosity within CPCs, and characterized the handling properties and physicochemical characteristics of CPCs containing GMPs. Samples were fabricated with four different weight fractions of GMPs (10, 20, 30, and 40%) and two different size ranges (100-150μm and 150-300μm), and were assayed for porosity, pore size distribution, morphology, and compressive mechanical properties. Samples were further tested for their handling properties - specifically, setting time and cohesiveness. Additionally, these same analyses were conducted on samples exposed to a physiological solution in order to estimate the dissolution kinetics of GMPs and its effect on the properties of the composite. GMPs were efficiently encapsulated and homogeneously dispersed in the resulting composite. Although setting times increased for GMP/CPC formulations compared to control CPC material, increasing the Na 2 HPO 4 concentration in the liquid phase decreased the initial setting time to clinically acceptable values (i.e. <15min). Incorporation of GMPs led to the formation of instant macroporosity upon cement setting, and encapsulated GMPs completely dissolved in three days, resulting in a further increase in scaffold porosity. However, the dissolution of GMPs decreased scaffold compressive strength. Overall, the introduction of GMPs into CPC resulted in macroporous scaffolds with good handling properties, as well as

Effect of endodontic cement on bone mineral density using serial dual-energy x-ray absorptiometry.

PubMed

Saghiri, Mohammad Ali; Orangi, Jafar; Tanideh, Nader; Janghorban, Kamal; Sheibani, Nader

2014-05-01

Materials with new compositions were tested in order to develop dental materials with better properties. Calcium silicate-based cements, including white mineral trioxide aggregate (WMTA), may improve osteopromotion because of their composition. Nano-modified cements may help researchers produce ideal root-end filling materials. Serial dual-energy x-ray absorptiometry measurement was used to evaluate the effects of particle size and the addition of tricalcium aluminate (C3A) to a type of mineral trioxide aggregate-based cement on bone mineral density and the surrounding tissues in the mandible of rabbits. Forty mature male rabbits (N = 40) were anesthetized, and a bone defect measuring 7 × 1 × 1 mm was created on the semimandible. The rabbits were divided into 2 groups, which were subdivided into 5 subgroups with 4 animals each based on the defect filled by the following: Nano-WMTA (patent application #13/211.880), WMTA (as standard), WMTA without C3A, Nano-WMTA + 2% Nano-C3A (Fujindonjnan Industrial Co, Ltd, Fujindonjnan Xiamen, China), and a control group. Twenty and forty days postoperatively, the animals were sacrificed, and the semimandibles were removed for DXA measurement. The Kruskal-Wallis test followed by the Mann-Whitney U test showed significant differences between the groups at a significance level of P < .05. P values calculated by the Kruskal-Wallis test were .002 for bone mineral density at both intervals and P20 day = .004 and P40 day = .005 for bone mineral content. This study showed that bone regeneration was enhanced by reducing the particle size (nano-modified) and C3A mixture. This may relate to the existence of an external supply of minerals and a larger surface area of nano-modified material, which may lead to faster release rate of Ca(2+), inducing bone formation. Adding Nano-C3A to Nano-WMTA may improve bone regeneration properties. Copyright © 2014 American Association of Endodontists. All rights reserved.

Short-fibre reinforcement of calcium phosphate bone cement.

PubMed

Buchanan, F; Gallagher, L; Jack, V; Dunne, N

2007-02-01

Calcium phosphate cement (CPC) sets to form hydroxyapatite, a major component of mineral bone, and is gaining increasing interest in bone repair applications. However, concerns regarding its brittleness and tendency to fragment have limited its widespread use. In the present study, short-fibre reinforcement of an apatitic calcium phosphate has been investigated to improve the fracture behaviour. The fibres used were polypropylene (PP) fibres, 50 microm in diameter and reduced in length by cryogenic grinding. The compressive strength and fracture behaviour were examined. Fibre addition of up to 10 wt % had a significant effect on composite properties, with the energy absorbed during failure being significantly increased, although this tended to be accompanied with a slight drop in compressive strength. The fibre reinforcement mechanisms appeared to be crack bridging and fibre pull-out. The setting time of the CPC with fibre reinforcement was also investigated and was found to increase with fibre volume fraction.

Stem Cells and Calcium Phosphate Cement Scaffolds for Bone Regeneration

PubMed Central

Wang, P.; Zhao, L.; Chen, W.; Liu, X.; Weir, M.D.; Xu, H.H.K.

2014-01-01

Calcium phosphate cements (CPCs) have excellent biocompatibility and osteoconductivity for dental, craniofacial, and orthopedic applications. This article reviews recent developments in stem cell delivery via CPC for bone regeneration. This includes: (1) biofunctionalization of the CPC scaffold, (2) co-culturing of osteoblasts/endothelial cells and prevascularization of CPC, (3) seeding of CPC with different stem cell species, (4) human umbilical cord mesenchymal stem cell (hUCMSC) and bone marrow MSC (hBMSC) seeding on CPC for bone regeneration, and (5) human embryonic stem cell (hESC) and induced pluripotent stem cell (hiPSC) seeding with CPC for bone regeneration. Cells exhibited good attachment/proliferation in CPC scaffolds. Stem-cell-CPC constructs generated more new bone and blood vessels in vivo than did the CPC control without cells. hUCMSCs, hESC-MSCs, and hiPSC-MSCs in CPC generated new bone and blood vessels similar to those of hBMSCs; hence, they were viable cell sources for bone engineering. CPC with hESC-MSCs and hiPSC-MSCs generated new bone two- to three-fold that of the CPC control. Therefore, this article demonstrates that: (1) CPC scaffolds are suitable for delivering cells; (2) hUCMSCs, hESCs, and hiPSCs are promising alternatives to hBMSCs, which require invasive procedures to harvest with limited cell quantity; and (3) stem-cell-CPC constructs are highly promising for bone regeneration in dental, craniofacial, and orthopedic applications. PMID:24799422

Setting characteristics and mechanical behaviour of a calcium phosphate bone cement containing tetracycline.

PubMed

Ratier, A; Gibson, I R; Best, S M; Freche, M; Lacout, J L; Rodriguez, F

2001-05-01

Calcium phosphate cements are used for bone defect filling and they may also be used as delivery systems for active agents. The physicochemical behaviour of an ionic cement, with a final composition of hydroxyapatite, containing tetracycline hydrochloride was investigated. Chemical characterisation, X-ray diffraction analysis, compressive strength and tensile strength were performed. It is known that the antibiotic can be adsorbed on calcium phosphate compounds and the presence of chloride ions can strongly influence the behaviour of the cement. Adding more than 1% (w/w) of 95% pure tetracycline hydrochloride in the solid phase led to a cement with poor mechanical properties, but which, in addition to hydroxyapatite, contained residual starting reagents. For this reason, experiments were also performed with tetracycline previously treated with a calcium sulphate solution. Using a treated tetracycline, it was possible to introduce at least 7% (w/w) of active ingredient whilst still allowing the reaction to proceed to completion i.e. the formation of hydroxyapatite with good mechanical properties. Therefore, treating the tetracycline HCI with calcium sulphate solution prior to reaction conserved the activity of the antibiotic, limited the influence of the antibiotic on the cement evolution and retained the physical properties of the cement.

Mesenchymal Stem Cells and Platelet Gel Improve Bone Deposition within CAD-CAM Custom-Made Ceramic HA Scaffolds for Condyle Substitution

PubMed Central

Ciocca, L.; Donati, D.; Ragazzini, S.; Dozza, B.; Rossi, F.; Fantini, M.; Spadari, A.; Romagnoli, N.; Landi, E.; Tampieri, A.; Piattelli, A.; Iezzi, G.; Scotti, R.

2013-01-01

Purpose. This study evaluated the efficacy of a regenerative approach using mesenchymal stem cells (MSCs) and CAD-CAM customized pure and porous hydroxyapatite (HA) scaffolds to replace the temporomandibular joint (TMJ) condyle. Methods. Pure HA scaffolds with a 70% total porosity volume were prototyped using CAD-CAM technology to replace the two temporomandibular condyles (left and right) of the same animal. MSCs were derived from the aspirated iliac crest bone marrow, and platelets were obtained from the venous blood of the sheep. Custom-made surgical guides were created by direct metal laser sintering and were used to export the virtual planning of the bone cut lines into the surgical environment. Sheep were sacrificed 4 months postoperatively. The HA scaffolds were explanted, histological specimens were prepared, and histomorphometric analysis was performed. Results. Analysis of the porosity reduction for apposition of newly formed bone showed a statistically significant difference in bone formation between condyles loaded with MSC and condyles without (P < 0.05). The bone ingrowth (BI) relative values of split-mouth comparison (right versus left side) showed a significant difference between condyles with and without MSCs (P < 0.05). Analysis of the test and control sides in the same animal using a split-mouth study design was performed; the condyle with MSCs showed greater bone formation. Conclusion. The split-mouth design confirmed an increment of bone regeneration into the HA scaffold of up to 797% upon application of MSCs. PMID:24073409

Mesenchymal stem cells and platelet gel improve bone deposition within CAD-CAM custom-made ceramic HA scaffolds for condyle substitution.

PubMed

Ciocca, L; Donati, D; Ragazzini, S; Dozza, B; Rossi, F; Fantini, M; Spadari, A; Romagnoli, N; Landi, E; Tampieri, A; Piattelli, A; Iezzi, G; Scotti, R

2013-01-01

This study evaluated the efficacy of a regenerative approach using mesenchymal stem cells (MSCs) and CAD-CAM customized pure and porous hydroxyapatite (HA) scaffolds to replace the temporomandibular joint (TMJ) condyle. Pure HA scaffolds with a 70% total porosity volume were prototyped using CAD-CAM technology to replace the two temporomandibular condyles (left and right) of the same animal. MSCs were derived from the aspirated iliac crest bone marrow, and platelets were obtained from the venous blood of the sheep. Custom-made surgical guides were created by direct metal laser sintering and were used to export the virtual planning of the bone cut lines into the surgical environment. Sheep were sacrificed 4 months postoperatively. The HA scaffolds were explanted, histological specimens were prepared, and histomorphometric analysis was performed. Analysis of the porosity reduction for apposition of newly formed bone showed a statistically significant difference in bone formation between condyles loaded with MSC and condyles without (P < 0.05). The bone ingrowth (BI) relative values of split-mouth comparison (right versus left side) showed a significant difference between condyles with and without MSCs (P < 0.05). Analysis of the test and control sides in the same animal using a split-mouth study design was performed; the condyle with MSCs showed greater bone formation. The split-mouth design confirmed an increment of bone regeneration into the HA scaffold of up to 797% upon application of MSCs.

Pullout strength of standard vs. cement-augmented rotator cuff repair anchors in cadaveric bone.

PubMed

Aziz, Keith T; Shi, Brendan Y; Okafor, Louis C; Smalley, Jeremy; Belkoff, Stephen M; Srikumaran, Uma

2018-05-01

We evaluate a novel method of rotator cuff repair that uses arthroscopic equipment to inject bone cement into placed suture anchors. A cadaver model was used to assess the pullout strength of this technique versus anchors without augmentation. Six fresh-frozen matched pairs of upper extremities were screened to exclude those with prior operative procedures, fractures, or neoplasms. One side from each pair was randomized to undergo standard anchor fixation with the contralateral side to undergo anchor fixation augmented with bone cement. After anchor fixation, specimens were mounted on a servohydraulic testing system and suture anchors were pulled at 90° to the insertion to simulate the anatomic pull of the rotator cuff. Sutures were pulled at 1 mm/s until failure. The mean pullout strength was 540 N (95% confidence interval, 389 to 690 N) for augmented anchors and 202 N (95% confidence interval, 100 to 305 N) for standard anchors. The difference in pullout strength was statistically significant (P < 0.05). This study shows superior pullout strength of a novel augmented rotator cuff anchor technique. The described technique, which is achieved by extruding polymethylmethacrylate cement through a cannulated in situ suture anchor with fenestrations, significantly increased the ultimate failure load in cadaveric human humeri. This novel augmented fixation technique was simple and can be implemented with existing instrumentation. In osteoporotic bone, it may substantially reduce the rate of anchor failure. Copyright © 2018 Elsevier Ltd. All rights reserved.

The structural changes in the bone tissue and regional lymph nodes when using bone cement

NASA Astrophysics Data System (ADS)

Zhukov, D. V.; Zajdman, A. M.; Prohorenko, V. M.; Ustikova, N. V.

2017-09-01

In orthopedics bone cement is used to replace defects. However, it is known that it possesses toxic properties, due to its composition monomer methyl methacrylate. There are some unresolved issues, in particular its local action, not investigated reaction of the immune system to respond to any fluctuations of endoecological equilibrium. All this helps to explain not only the intraoperative complications such as acute heart and lung failure, but also many deferred pathological processes, complications in the postoperative period.

Maxillary sinus floor elevation using a tissue-engineered bone with calcium-magnesium phosphate cement and bone marrow stromal cells in rabbits.

PubMed

Zeng, Deliang; Xia, Lunguo; Zhang, Wenjie; Huang, Hui; Wei, Bin; Huang, Qingfeng; Wei, Jie; Liu, Changsheng; Jiang, Xinquan

2012-04-01

The objective of this study was to assess the effects of maxillary sinus floor elevation with a tissue-engineered bone constructed with bone marrow stromal cells (bMSCs) and calcium-magnesium phosphate cement (CMPC) material. The calcium (Ca), magnesium (Mg), and phosphorus (P) ions released from calcium phosphate cement (CPC), magnesium phosphate cement (MPC), and CMPC were detected by inductively coupled plasma atomic emission spectroscopy (ICP-AES), and the proliferation and osteogenic differentiation of bMSCs seeded on CPC, MPC, and CMPC or cultured in CPC, MPC, and CMPC extracts were measured by MTT analysis, alkaline phosphatase (ALP) activity assay, alizarin red mineralization assay, and real-time PCR analysis of the osteogenic genes ALP and osteocalcin (OCN). Finally, bMSCs were combined with CPC, MPC, and CMPC and used for maxillary sinus floor elevation in rabbits, while CPC, MPC, or CMPC without cells served as control groups. The new bone formation in each group was detected by histological finding and fluorochrome labeling at weeks 2 and 8 after surgical operation. It was observed that the Ca ion concentrations of the CMPC and CPC scaffolds was significantly higher than that of the MPC scaffold, while the Mg ions concentration of CMPC and MPC was significantly higher than that of CPC. The bMSCs seeded on CMPC and MPC or cultured in their extracts proliferated more quickly than the cells seeded on CPC or cultured in its extract, respectively. The osteogenic differentiation of bMSCs seeded on CMPC and CPC or cultured in the corresponding extracts was significantly enhanced compared to that of bMSCs seeded on MPC or cultured in its extract; however, there was no significant difference between CMPC and CPC. As for maxillary sinus floor elevation in vivo, CMPC could promote more new bone formation and mineralization compared to CPC and MPC, while the addition of bMSCs could further enhance its new bone formation ability significantly. Our data suggest that

Release of zirconia nanoparticles at the metal stem-bone cement interface in implant loosening of total hip replacements.

PubMed

Schunck, Antje; Kronz, Andreas; Fischer, Cornelius; Buchhorn, Gottfried Hans

2016-02-01

In a previous failure analysis performed on femoral components of cemented total hip replacements, we determined high volumes of abraded bone cement. Here, we describe the topography of the polished surface of polymethyl methacrylate (PMMA) bone cement containing zirconia radiopacifier, analyzed by scanning electron microscopy and vertical scanning interferometry. Zirconia spikes protruded about 300nm from the PMMA matrix, with pits of former crystal deposition measuring about 400nm in depth. We deduced that the characteristically mulberry-shaped agglomerates of zirconia crystals are ground and truncated into flat surfaces and finally torn out of the PMMA matrix. Additionally, evaluation of in vitro PMMA-on-PMMA articulation confirmed that crystal agglomerations of zirconia were exposed to grain pullout, fatigue, and abrasion. In great quantities, micron-sized PMMA wear and zirconia nanoparticles accumulate in the cement-bone interface and capsular tissues, thereby contributing to osteolysis. Dissemination of nanoparticles to distant lymph nodes and organs of storage has been reported. As sufficient information is lacking, foreign body reactions to accumulated nanosized zirconia in places of long-term storage should be investigated. The production of wear particles of PMMA bone cement in the interface to joint replacement devices, presents a local challenge. The presence of zirconia particles results in frustrated digestion attempts by macrophages, liberation of inflammatory mediators, and necrosis leading to aseptic inflammation and osteolyses. Attempts to minimize wear of articulating joints reduced the attention to the deterioration of cement cuffs. We therefore investigated polished surfaces of retrieved cuffs to demonstrate their morphology and to measure surface roughness. Industrially admixed agglomerates of the radiopacifier are abraded to micron and nano-meter sized particles. The dissemination of zirconia particles in the reticulo-endothelial system to

Fabrication and characterization of a novel carbon fiber-reinforced calcium phosphate silicate bone cement with potential osteo-inductivity.

PubMed

Zheng, Jiangjiang; Xiao, Yu; Gong, Tianxing; Zhou, Shuxin; Troczynski, Tom; Yang, Quanzu; Bao, Chongyun; Xu, Xiaoming

2015-12-23

The repair of bone defects is still a pressing challenge in clinics. Injectable bone cement is regarded as a promising material to solve this problem because of its special self-setting property. Unfortunately, its poor mechanical conformability, unfavorable osteo-genesis ability and insufficient osteo-inductivity seriously limit its clinical application. In this study, novel experimental calcium phosphate silicate bone cement reinforced by carbon fibers (CCPSC) was fabricated and characterized. First, a compressive strength test and cell culture study were carried out. Then, the material was implanted into the femoral epiphysis of beagle dogs to further assess its osteo-conductivity using a micro-computed tomography scan and histological analysis. In addition, we implanted CCPSC into the beagles' intramuscular pouches to perform an elementary investigation of its osteo-inductivity. The results showed that incorporation of carbon fibers significantly improved its mechanical properties. Meanwhile, CCPSC had better biocompatibility to activate cell adhesion as well as proliferation than poly-methyl methacrylate bone cement based on the cell culture study. Moreover, pronounced biodegradability and improved osteo-conductivity of CCPSC could be observed through the in vivo animal study. Finally, a small amount of osteoid was found at the heterotopic site one month after implantation which indicated potential osteo-inductivity of CCPSC. In conclusion, the novel CCPSC shows promise as a bioactive bone substitute in certain load-bearing circumstances.

The use of water-jetting technology in prostheses revision surgery-first results of parameter studies on bone and bone cement.

PubMed

Honl, M; Rentzsch, R; Müller, G; Brandt, C; Bluhm, A; Hille, E; Louis, H; Morlock, M

2000-01-01

Water-jet cutting techniques have been used in industrial applications for many different materials. Recently these techniques have been developed into a revolutionary cutting tool for soft tissues in visceral surgery. The present study investigates the usage of this cutting technology for the revision surgery of endoprostheses. In the first part of the study, samples of bovine bone and acrylic bone cement (PMMA) were cut using an industrial jet cutting device with pure water. Below 400 bar, only PMMA was cut; above 400 bar, bone was also cut, but only pressures above 800 bar resulted in clinically useful rates of material removal (cut depth 2. 4 mm at 10 mm/min traverse speed). In the second part of the study, the effect of adding biocompatible abrasives to the water in order to reduce the required pressure was investigated, resulting in a significantly higher removal of material. At 600 bar, PMMA was cut 5. 2 mm deep with plain water and 15.2 mm deep with added abrasives. The quality of the cuts was increased by the abrasive. Though there was no clear selectivity between bone and PMMA any more, the rate of material removal at similar pressures was significantly higher for PMMA than for bone (600 bar: 1.6 mm cut depth for bone samples, 15.2 mm for PMMA). The measured cut depths with either method were not influenced by a change of the cutting direction with respect to the main direction of the osteons in the bone. However, a reduction of the jet surface angle (90 degrees to 23 degrees ) resulted for bone in a significantly lower cut depth at 600 bar (plain water: 0.62 mm vs. 0.06 mm; abrasive: 1.61 mm vs. 0.60 mm). The laboratory experiments indicate that abrasive water jets may be suitable for cutting biomaterials like bone and bone cement. Copyright 2000 John Wiley & Sons, Inc.

Calcium Orthophosphate Cements and Concretes

PubMed Central

Dorozhkin, Sergey V.

2009-01-01

In early 1980s, researchers discovered self-setting calcium orthophosphate cements, which are a bioactive and biodegradable grafting material in the form of a powder and a liquid. Both phases form after mixing a viscous paste that after being implanted, sets and hardens within the body as either a non-stoichiometric calcium deficient hydroxyapatite (CDHA) or brushite, sometimes blended with unreacted particles and other phases. As both CDHA and brushite are remarkably biocompartible and bioresorbable (therefore, in vivo they can be replaced with newly forming bone), calcium orthophosphate cements represent a good correction technique for non-weight-bearing bone fractures or defects and appear to be very promising materials for bone grafting applications. Besides, these cements possess an excellent osteoconductivity, molding capabilities and easy manipulation. Furthermore, reinforced cement formulations are available, which in a certain sense might be described as calcium orthophosphate concretes. The concepts established by calcium orthophosphate cement pioneers in the early 1980s were used as a platform to initiate a new generation of bone substitute materials for commercialization. Since then, advances have been made in the composition, performance and manufacturing; several beneficial formulations have already been introduced as a result. Many other compositions are in experimental stages. In this review, an insight into calcium orthophosphate cements and concretes, as excellent biomaterials suitable for both dental and bone grafting application, has been provided.

Complexity in modeling of residual stresses and strains during polymerization of bone cement: effects of conversion, constraint, heat transfer, and viscoelastic property changes.

PubMed

Gilbert, Jeremy L

2006-12-15

Aseptic loosening of cemented joint prostheses remains a significant concern in orthopedic biomaterials. One possible contributor to cement loosening is the development of porosity, residual stresses, and local fracture of the cement that may arise from the in-situ polymerization of the cement. In-situ polymerization of acrylic bone cement is a complex set of interacting processes that involve polymerization reactions, heat generation and transfer, full or partial mechanical constraint, evolution of conversion- and temperature-dependent viscoelastic material properties, and thermal and conversion-driven changes in the density of the cement. Interactions between heat transfer and polymerization can lead to polymerization fronts moving through the material. Density changes during polymerization can, in the presence of mechanical constraint, lead to the development of locally high residual strain energy and residual stresses. This study models the interactions during bone cement polymerization and determines how residual stresses develop in cement and incorporates temperature and conversion-dependent viscoelastic behavior. The results show that the presence of polymerization fronts in bone cement result in locally high residual strain energies. A novel heredity integral approach is presented to track residual stresses incorporating conversion and temperature dependent material property changes. Finally, the relative contribution of thermal- and conversion-dependent strains to residual stresses is evaluated and it is found that the conversion-based strains are the major contributor to the overall behavior. This framework provides the basis for understanding the complex development of residual stresses and can be used as the basis for developing more complex models of cement behavior.

Blooming gelatin: an individual additive for enhancing nanoapatite precipitation, physical properties, and osteoblastic responses of nanostructured macroporous calcium phosphate bone cements.

PubMed

Orshesh, Ziba; Hesaraki, Saeed; Khanlarkhani, Ali

2017-01-01

In recent years, there has been a great interest in using natural polymers in the composition of calcium phosphate bone cements to enhance their physical, mechanical, and biological performance. Gelatin is a partially hydrolyzed form of collagen, a natural component of bone matrix. In this study, the effect of blooming gelatin on the nanohydroxyapatite precipitation, physical and mechanical properties, and cellular responses of a calcium phosphate bone cement (CPC) was investigated. Various concentrations of blooming gelatin (2, 5, and 8 wt.%) were used as the cement liquid and an equimolar mixture of tetracalcium phosphate and dicalcium phosphate was used as solid phase. The CPC without any gelatin additive was also evaluated as a control group. The results showed that gelatin accelerated hydraulic reactions of the cement paste, in which the reactants were immediately converted into nanostructured apatite precipitates after hardening. Gelatin molecules induced 4%-10% macropores (10-300 μm) into the cement structure, decreased initial setting time by ~190%, and improved mechanical strength of the as-set cement. Variation in the above-mentioned properties was influenced by the gelatin concentration and progressed with increasing the gelatin content. The numbers of the G-292 osteoblastic cells on gelatin-containing CPCs were higher than the control group at entire culture times (1-14 days), meanwhile better alkaline phosphatase (ALP) activity was determined using blooming gelatin additive. The observation of cell morphologies on the cement surfaces revealed an appropriate cell attachment with extended cell membranes on the cements. Overall, adding gelatin to the composition of CPC improved the handling characteristics such as setting time and mechanical properties, enhanced nanoapatite precipitation, and augmented the early cell proliferation rate and ALP activity.

Osteoclastic differentiation and resorption is modulated by bioactive metal ions Co2+, Cu2+ and Cr3+ incorporated into calcium phosphate bone cements

PubMed Central

Bernhardt, Anne; Schamel, Martha; Gbureck, Uwe; Gelinsky, Michael

2017-01-01

Biologically active metal ions in low doses have the potential to accelerate bone defect healing. For successful remodelling the interaction of bone graft materials with both bone-forming osteoblasts and bone resorbing osteoclasts is crucial. In the present study brushite forming calcium phosphate cements (CPC) were doped with Co2+, Cu2+ and Cr3+ and the influence of these materials on osteoclast differentiation and activity was examined. Human osteoclasts were differentiated from human peripheral blood mononuclear cells (PBMC) both on the surface and in indirect contact to the materials on dentin discs. Release of calcium, phosphate and bioactive metal ions was determined using ICP-MS both in the presence and absence of the cells. While Co2+ and Cu2+ showed a burst release, Cr3+ was released steadily at very low concentrations (below 1 μM) and both calcium and phosphate release of the cements was considerably changed in the Cr3+ modified samples. Direct cultivation of PBMC/osteoclasts on Co2+ cements showed lower attached cell number compared to the reference but high activity of osteoclast specific enzymes tartrate resistant acid phosphatase (TRAP), carbonic anhydrase II (CAII) and cathepsin K (CTSK) and significantly increased gene expression of vitronectin receptor. Indirect cultivation with diluted Co2+ cement extracts revealed highest resorbed area compared to all other modifications and the reference. Cu2+ cements had cytotoxic effect on PBMC/osteoclasts during direct cultivation, while indirect cultivation with diluted extracts from Cu2+ cements did not provoke cytotoxic effects but a strictly inhibited resorption. Cr3+ doped cements did not show cytotoxic effects at all. Gene expression and enzyme activity of CTSK was significantly increased in direct culture. Indirect cultivation with Cr3+ doped cements revealed significantly higher resorbed area compared to the reference. In conclusion Cr3+ doped calcium phosphate cements are an innovative cement

Osteoclastic differentiation and resorption is modulated by bioactive metal ions Co2+, Cu2+ and Cr3+ incorporated into calcium phosphate bone cements.

PubMed

Bernhardt, Anne; Schamel, Martha; Gbureck, Uwe; Gelinsky, Michael

2017-01-01

Biologically active metal ions in low doses have the potential to accelerate bone defect healing. For successful remodelling the interaction of bone graft materials with both bone-forming osteoblasts and bone resorbing osteoclasts is crucial. In the present study brushite forming calcium phosphate cements (CPC) were doped with Co2+, Cu2+ and Cr3+ and the influence of these materials on osteoclast differentiation and activity was examined. Human osteoclasts were differentiated from human peripheral blood mononuclear cells (PBMC) both on the surface and in indirect contact to the materials on dentin discs. Release of calcium, phosphate and bioactive metal ions was determined using ICP-MS both in the presence and absence of the cells. While Co2+ and Cu2+ showed a burst release, Cr3+ was released steadily at very low concentrations (below 1 μM) and both calcium and phosphate release of the cements was considerably changed in the Cr3+ modified samples. Direct cultivation of PBMC/osteoclasts on Co2+ cements showed lower attached cell number compared to the reference but high activity of osteoclast specific enzymes tartrate resistant acid phosphatase (TRAP), carbonic anhydrase II (CAII) and cathepsin K (CTSK) and significantly increased gene expression of vitronectin receptor. Indirect cultivation with diluted Co2+ cement extracts revealed highest resorbed area compared to all other modifications and the reference. Cu2+ cements had cytotoxic effect on PBMC/osteoclasts during direct cultivation, while indirect cultivation with diluted extracts from Cu2+ cements did not provoke cytotoxic effects but a strictly inhibited resorption. Cr3+ doped cements did not show cytotoxic effects at all. Gene expression and enzyme activity of CTSK was significantly increased in direct culture. Indirect cultivation with Cr3+ doped cements revealed significantly higher resorbed area compared to the reference. In conclusion Cr3+ doped calcium phosphate cements are an innovative cement

Impact of implant size on cement filling in hip resurfacing arthroplasty.

PubMed

de Haan, Roel; Buls, Nico; Scheerlinck, Thierry

2014-01-01

Larger proportions of cement within femoral resurfacing implants might result in thermal bone necrosis. We postulate that smaller components are filled with proportionally more cement, causing an elevated failure rate. A total of 19 femoral heads were fitted with polymeric replicas of ReCap (Biomet) resurfacing components fixed with low-viscosity cement. Two specimens were used for each even size between 40 and 56 mm and one for size 58 mm. All specimens were imaged with computed tomography, and the cement thickness and bone density were analyzed. The average cement mantle thickness was 2.63 mm and was not correlated with the implant size. However, specimen with low bone density had thicker cement mantles regardless of size. The average filling index was 36.65% and was correlated to both implant size and bone density. Smaller implants and specimens with lower bone density contained proportionally more cement than larger implants. According to a linear regression model, bone density but not implant size influenced cement thickness. However, both implant size and bone density had a significant impact on the filling index. Large proportions of cement within the resurfacing head have the potential to generate thermal bone necrosis and implant failure. When considering hip resurfacing in patients with a small femoral head and/or osteoporotic bone, extra care should be taken to avoid thermal bone necrosis, and alternative cementing techniques or even cementless implants should be considered. This study should help delimiting the indications for hip resurfacing and to choose an optimal cementing technique taking implant size into account.

Physical and mechanical properties of PMMA bone cement reinforced with nano-sized titania fibers.

PubMed

Khaled, S M Z; Charpentier, Paul A; Rizkalla, Amin S

2011-02-01

X-ray contrast medium (BaSO(4) or ZrO(2)) used in commercially available PMMA bone cements imparts a detrimental effect on mechanical properties, particularly on flexural strength and fracture toughness. These lower properties facilitate the chance of implant loosening resulting from cement mantle failure. The present study was performed to examine the mechanical properties of a commercially available cement (CMW1) by introducing novel nanostructured titania fibers (n-TiO(2) fibers) into the cement matrix, with the fibers acting as a reinforcing phase. The hydrophilic nature of the n-TiO(2) fibers was modified by using a bifunctional monomer, methacrylic acid. The n-TiO(2) fiber content of the cement was varied from 0 to 2 wt%. Along with the mechanical properties (fracture toughness (K (IC)), flexural strength (FS), and flexural modulus (FM)) of the reinforced cements the following properties were investigated: complex viscosity-versus-time, maximum polymerization temperature (T (max)), dough time (t (dough)), setting time (t (set)), radiopacity, and in vitro biocompatibility. On the basis of the determined mechanical properties, the optimized composition was found at 1 wt% n-TiO(2) fibers, which provided a significant increase in K (IC) (63%), FS (20%), and FM (22%), while retaining the handling properties and in vitro biocompatibility compared to that exhibited by the control cement (CMW1). Moreover, compared to the control cement, there was no significant change in the radiopacity of any of the reinforced cements at p = 0.05. This study demonstrated a novel pathway to augment the mechanical properties of PMMA-based cement by providing an enhanced interfacial interaction and strong adhesion between the functionalized n-TiO( 2) fibers and PMMA matrix, which enhanced the effective load transfer within the cement.

The economics of using prophylactic antibiotic-loaded bone cement in total knee replacement.

PubMed

Gutowski, C J; Zmistowski, B M; Clyde, C T; Parvizi, J

2014-01-01

The rate of peri-prosthetic infection following total joint replacement continues to rise, and attempts to curb this trend have included the use of antibiotic-loaded bone cement at the time of primary surgery. We have investigated the clinical- and cost-effectiveness of the use of antibiotic-loaded cement for primary total knee replacement (TKR) by comparing the rate of infection in 3048 TKRs performed without loaded cement over a three-year period versus the incidence of infection after 4830 TKRs performed with tobramycin-loaded cement over a later period of time of a similar duration. In order to adjust for confounding factors, the rate of infection in 3347 and 4702 uncemented total hip replacements (THR) performed during the same time periods, respectively, was also examined. There were no significant differences in the characteristics of the patients in the different cohorts. The absolute rate of infection increased when antibiotic-loaded cement was used in TKR. However, this rate of increase was less than the rate of increase in infection following uncemented THR during the same period. If the rise in the rate of infection observed in THR were extrapolated to the TKR cohort, 18 additional cases of infection would have been expected to occur in the cohort receiving antibiotic-loaded cement, compared with the number observed. Depending on the type of antibiotic-loaded cement that is used, its cost in all primary TKRs ranges between USD $2112.72 and USD $112 606.67 per case of infection that is prevented.

Pre-packed vacuum bone cement mixing systems. A further step in reducing methylmethacrylate exposure in surgery.

PubMed

Schlegel, Ulf J; Sturm, Michael; Eysel, Peer; Breusch, Steffen J

2010-11-01

Polymethylmethacrylate bone cements are widely used in orthopaedic and trauma surgery as well as in dentistry. The toxic side effects of inhaled methylmethacrylate (MMA) fumes generated during mixing have been well studied. Vacuum cement mixing systems have been shown to reduce the risk of airborne MMA significantly compared to handmixing. In an effort to further reduce MMA exposure, the latest generation of mixing devices are pre-packed with the ingredients and thus allow preparation in nearly closed circuits. Until now, there has been no study proofing the efficacy of those systems in protecting theatre staff from MMA vapours. A pre-packed vacuum mixing system (Optipac®) was compared with two standard systems (Palamix® and Easymix®) regarding MMA emission. The latter systems require loading with the bone cement compounds prior to mixing. Following a standardized procedure, 10 mixes were performed with each system and the emission of MMA vapours in the breathing zone was recorded using photoionization detection over a period of 3 min. The mean MMA exposure was reduced when using the pre-packed system compared to the devices that require filling with the components. The highest emission peaks were recorded during the mixing and preparation steps in all systems. Modern pre-packed vacuum mixing systems further help to reduce the occupational hazards created by bone cement preparation. However, MMA fumes can still be detected using this technique. Although this is an important step in reducing MMA exposure in the operating theatre, further technical effort has to be taken to eliminate the continuous leakage of monomer from the devices while mixing and to minimize necessary manipulation for final delivery.

Intralesional curettage and cementation for low-grade chondrosarcoma of long bones: retrospective study and literature review.

PubMed

Mermerkaya, Musa Ugur; Bekmez, Senol; Karaaslan, Fatih; Danisman, Murat; Kosemehmetoglu, Kemal; Gedikoglu, Gokhan; Ayvaz, Mehmet; Tokgozoglu, Ahmet Mazhar

2014-11-10

Various treatment strategies for low-grade chondrosarcomas with variable outcomes have been reported in the literature. The aim of this study was to assess the oncological and functional outcomes associated with intralesional curettage followed by adjuvant therapy comprising high-speed burring, thermal cauterization, and bone cementation with polymethylmethacrylate. We performed a retrospective review of 21 consecutive patients with intramedullary low-grade chondrosarcoma of long bones treated by intralesional curettage and adjuvant therapy comprising high-speed burring, thermal cauterization, and cementation at our institution from 2007 to 2012. The average age of the patients was 48.7 (range, 18-71) years. There were 7 male and 14 female patients. The mean follow-up period was 58.4 (range, 26-85) months after surgery. The treated lesions were located in the proximal humerus (n=10), proximal tibia (n=6), and distal femur (n=5). At the average follow-up time point of 58.4 (range, 26-85) months, no patient had developed local recurrence and no distant metastases were observed. The average Musculoskeletal Tumor Society score among all 21 patients was 95% (84-100). The combination of intralesional curettage, application of high-speed burring, thermal cauterization, and cementation is an effective treatment strategy for low-grade intramedullary chondrosarcoma of long bones. Excellent oncological and functional results can be obtained.

Microleakage under orthodontic bands cemented with nano-hydroxyapatite-modified glass ionomer.

PubMed

Enan, Enas T; Hammad, Shaza M

2013-11-01

To estimate the in vivo effect of nano-hydroxyapatite (HA) modification of banding glass-ionomer cement on microleakage under orthodontic bands. Eighty noncarious premolars scheduled for extraction in 20 orthodontic patients were randomly divided into four groups. Grouping was based on the ratio of nano-HA (0%, 5%, 10%, 15% by weight) added to the luting glass-ionomer cement (GIC) Ketac-Cem, which was used for cementation of prefabricated micro-etched orthodontic bands. Dye penetration method was used for microleakage evaluation at the cement-band and cement-enamel interfaces. Statistical evaluation was performed with a Kruskal-Wallis test and a Mann-Whitney U-test, and a Bonferroni-adjusted significance level was calculated. Bands cemented with conventional GIC showed the highest microleakage scores in comparison to those cemented with nano-HA-modified GIC. No significant difference was found between teeth banded with 10% and 15% modified GIC. Modification of the banding GIC with 15% nano-HA revealed a positive effect on reducing microleakage around orthodontic bands.

Fixation of a human rib by an intramedullary telescoping splint anchored by bone cement.

PubMed

Liovic, Petar; Šutalo, Ilija D; Marasco, Silvana F

2016-09-01

A novel concept for rib fixation is presented that involves the use of a bioresorbable polymer intramedullary telescoping splint. Bone cement is used to anchor each end of the splint inside the medullary canal on each side of the fracture site. In this manner, rib fixation is achieved without fixation device protrusion from the rib, making the splint completely intramedullary. Finite element analysis is used to demonstrate that such a splint/cement composite can preserve rib fixation subjected to cough-intensity force loadings. Computational fluid dynamics and porcine rib experiments were used to study the anchor formation process required to complete the fixation.

Blooming gelatin: an individual additive for enhancing nanoapatite precipitation, physical properties, and osteoblastic responses of nanostructured macroporous calcium phosphate bone cements

PubMed Central

Orshesh, Ziba; Hesaraki, Saeed; Khanlarkhani, Ali

2017-01-01

In recent years, there has been a great interest in using natural polymers in the composition of calcium phosphate bone cements to enhance their physical, mechanical, and biological performance. Gelatin is a partially hydrolyzed form of collagen, a natural component of bone matrix. In this study, the effect of blooming gelatin on the nanohydroxyapatite precipitation, physical and mechanical properties, and cellular responses of a calcium phosphate bone cement (CPC) was investigated. Various concentrations of blooming gelatin (2, 5, and 8 wt.%) were used as the cement liquid and an equimolar mixture of tetracalcium phosphate and dicalcium phosphate was used as solid phase. The CPC without any gelatin additive was also evaluated as a control group. The results showed that gelatin accelerated hydraulic reactions of the cement paste, in which the reactants were immediately converted into nanostructured apatite precipitates after hardening. Gelatin molecules induced 4%–10% macropores (10–300 μm) into the cement structure, decreased initial setting time by ~190%, and improved mechanical strength of the as-set cement. Variation in the above-mentioned properties was influenced by the gelatin concentration and progressed with increasing the gelatin content. The numbers of the G-292 osteoblastic cells on gelatin-containing CPCs were higher than the control group at entire culture times (1–14 days), meanwhile better alkaline phosphatase (ALP) activity was determined using blooming gelatin additive. The observation of cell morphologies on the cement surfaces revealed an appropriate cell attachment with extended cell membranes on the cements. Overall, adding gelatin to the composition of CPC improved the handling characteristics such as setting time and mechanical properties, enhanced nanoapatite precipitation, and augmented the early cell proliferation rate and ALP activity. PMID:28176961

Just a drop of cement: a case of cervical spine bone aneurysmal cyst successfully treated by percutaneous injection of a small amount of polymethyl-methacrylate cement

PubMed Central

Fahed, Robert; Clarençon, Frédéric; Riouallon, Guillaume; Cormier, Evelyne; Bonaccorsi, Raphael; Pascal-Mousselard, Hugues; Chiras, Jacques

2014-01-01

Aneurysmal bone cyst (ABC) is a benign hemorrhagic tumor, commonly revealed by local pain. The best treatment for this lesion is still controversial. We report the case of a patient with chronic neck pain revealing an ABC of the third cervical vertebra. After percutaneous injection of a small amount of polymethyl-methacrylate bone cement, the patient experienced significant clinical and radiological improvement. PMID:25498806

Just a drop of cement: a case of cervical spine bone aneurysmal cyst successfully treated by percutaneous injection of a small amount of polymethyl-methacrylate cement.

PubMed

Fahed, Robert; Clarençon, Frédéric; Riouallon, Guillaume; Cormier, Evelyne; Bonaccorsi, Raphael; Pascal-Mousselard, Hugues; Chiras, Jacques

2014-12-12

Aneurysmal bone cyst (ABC) is a benign hemorrhagic tumor, commonly revealed by local pain. The best treatment for this lesion is still controversial. We report the case of a patient with chronic neck pain revealing an ABC of the third cervical vertebra. After percutaneous injection of a small amount of polymethyl-methacrylate bone cement, the patient experienced significant clinical and radiological improvement. 2014 BMJ Publishing Group Ltd.

Biomechanical evaluation of fixation of intra-articular fractures of the distal part of the radius in cadavera: Kirschner wires compared with calcium-phosphate bone cement.

PubMed

Yetkinler, D N; Ladd, A L; Poser, R D; Constantz, B R; Carter, D

1999-03-01

The purpose of this study was to compare the biomechanical efficacy of an injectable calcium-phosphate bone cement (Skeletal Repair System [SRS]) with that of Kirschner wires for the fixation of intraarticular fractures of the distal part of the radius. Colles fractures (AO pattern, C2.1) were produced in ten pairs of fresh-frozen human cadaveric radii. One radius from each pair was randomly chosen for stabilization with SRS bone cement. These ten radii were treated with open incision, impaction of loose cancellous bone with use of a Freer elevator, and placement of the SRS bone cement by injection. In the ten control specimens, the fracture was stabilized with use of two horizontal and two oblique Kirschner wires. The specimens were cyclically loaded to a peak load of 200 newtons for 2000 cycles to evaluate the amount of settling, or radial shortening, under conditions simulating postoperative loading with the limb in a cast. Each specimen then was loaded to failure to determine its ultimate strength. The amount of radial shortening was highly variable among the specimens, but it was consistently higher in the Kirschner-wire constructs than in the bone fixed with SRS bone cement within each pair of radii. The range of shortening for all twenty specimens was 0.18 to 4.51 millimeters. The average amount of shortening in the SRS constructs was 50 percent of that in the Kirschner-wire constructs (0.51+/-0.34 compared with 1.01+/-1.23 millimeters; p = 0.015). With the numbers available, no significant difference in ultimate strength was detected between the two fixation groups. This study showed that fixation of an intra-articular fracture of the distal part of a cadaveric radius with biocompatible calcium-phosphate bone cement produced results that were biomechanically comparable with those produced by fixation with Kirschner wires. However, the constructs that were fixed with calcium-phosphate bone cement demonstrated less shortening under simulated cyclic load-bearing.

Can cemented dual-mobility cups be used without a reinforcement device in cases of mild acetabular bone stock alteration in total hip arthroplasty?

PubMed

Haen, T X; Lonjon, G; Vandenbussche, E

2015-12-01

Cemented versions of dual-mobility cups (DMCs), helpful in cases of bone stock alteration, are usually used in association with a reinforcement device. To simplify the intervention in elderly subjects or those with a poor bone stock, the cups can be cemented directly into the bone, but the long-term result remains uncertain. We conducted a retrospective study in this population so as to: (1) assess whether cemented fixation of a DMC without a reinforcement device leads to a higher loosening rate, (2) confirm its efficacy in preventing dislocations in subjects at high risk of instability, and (3) measure the functional results. Cemented fixation of a DMC is reliable in cases of moderate alteration of bone stock. Sixty-four patients (66 hips) undergoing implantation of a cemented DMC (Saturne™) without a reinforcement device were included in this single-center retrospective study. Their mean age was 79.8 years (range, 40-95 years). The indications varied: hip osteoarthritis (30.3%), prosthesis revision (44.0%), and trauma (25.8%). The patients were evaluated radiologically and clinically at follow-up. The main evaluation criterion was the revision rate for aseptic loosening. Dislocations, the infection rate, and the Postel Merle d'Aubigné (PMA) score were noted. At the mean follow-up of 4.2 years, three (4.6%) patients had been lost to follow-up and 22 (33.3%) had died. There was one case of aseptic loosening (1.5%). Cup survival was 98% at 5 years (95%CI [94-100]). There were no dislocations. There was one revision for infection. The mean PMA score was 15.5 (range, 9-18). The frequency of acetabular loosening was comparable to the frequency in cemented DMCs with a reinforcement device. A cemented DMC without a reinforcement device is possible and is a simple and viable option when there is moderate bone stock alteration. IV, retrospective cohort study. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Bone Repair and Military Readiness

DTIC Science & Technology

2015-10-01

Even though commercial bone cements have not significantly changed in the past 50 years and have been used throughout the world, there are...generation. In addition, it appears that this new bone cement is actually supportive of new bone formation. A cement that can achieve true integration...problem. As the proposed bone cement prototype polymerizes at a much lower temperature, antibiotics that are sensitive to heat can be added to the cement

Effect of gamma radiation and accelerated aging on the mechanical and thermal behavior of HDPE/HA nano-composites for bone tissue regeneration

PubMed Central

2013-01-01

Background The replacement of hard tissues demands biocompatible and sometimes bioactive materials with properties similar to those of bone. Nano-composites made of biocompatible polymers and bioactive inorganic nano particles such as HDPE/HA have attracted attention as permanent bone substitutes due to their excellent mechanical properties and biocompatibility. Method The HDPE/HA nano-composite is prepared using melt blending at different HA loading ratios. For evaluation of the degradation by radiation, gamma rays of 35 kGy, and 70 kGy were used to irradiate the samples at room temperature in vacuum. The effects of accelerated ageing after gamma irradiation on morphological, mechanical and thermal properties of HDPE/HA nano-composites were measured. Results In Vitro test results showed that the HDPE and all HDPE/HA nano-composites do not exhibit any cytotoxicity to WISH cell line. The results also indicated that the tensile properties of HDPE/HA nano-composite increased with increasing the HA content except fracture strain decreased. The dynamic mechanical analysis (DMA) results showed that the storage and loss moduli increased with increasing the HA ratio and the testing frequency. Finally, it is remarked that all properties of HDPE/HA is dependent on the irradiation dose and accelerated aging. Conclusion Based on the experimental results, it is found that the addition of 10%, 20% and 30% HA increases the HDPE stiffness by 23%, 44 and 59% respectively. At the same time, the G’ increased from 2.25E11 MPa for neat HDPE to 4.7E11 MPa when 30% HA was added to the polymer matrix. Also, significant improvements in these properties have been observed due to irradiation. Finally, the overall properties of HDPE and its nano-composite properties significantly decreased due to aging and should be taken into consideration in the design of bone substitutes. It is attributed that the developed HDPE/HA nano-composites could be a good alternative material for bone tissue

Effect of gamma radiation and accelerated aging on the mechanical and thermal behavior of HDPE/HA nano-composites for bone tissue regeneration.

PubMed

Alothman, Othman Y; Almajhdi, Fahad N; Fouad, H

2013-09-24

The replacement of hard tissues demands biocompatible and sometimes bioactive materials with properties similar to those of bone. Nano-composites made of biocompatible polymers and bioactive inorganic nano particles such as HDPE/HA have attracted attention as permanent bone substitutes due to their excellent mechanical properties and biocompatibility. The HDPE/HA nano-composite is prepared using melt blending at different HA loading ratios. For evaluation of the degradation by radiation, gamma rays of 35 kGy, and 70 kGy were used to irradiate the samples at room temperature in vacuum. The effects of accelerated ageing after gamma irradiation on morphological, mechanical and thermal properties of HDPE/HA nano-composites were measured. In Vitro test results showed that the HDPE and all HDPE/HA nano-composites do not exhibit any cytotoxicity to WISH cell line. The results also indicated that the tensile properties of HDPE/HA nano-composite increased with increasing the HA content except fracture strain decreased. The dynamic mechanical analysis (DMA) results showed that the storage and loss moduli increased with increasing the HA ratio and the testing frequency. Finally, it is remarked that all properties of HDPE/HA is dependent on the irradiation dose and accelerated aging. Based on the experimental results, it is found that the addition of 10%, 20% and 30% HA increases the HDPE stiffness by 23%, 44 and 59% respectively. At the same time, the G' increased from 2.25E11 MPa for neat HDPE to 4.7E11 MPa when 30% HA was added to the polymer matrix. Also, significant improvements in these properties have been observed due to irradiation. Finally, the overall properties of HDPE and its nano-composite properties significantly decreased due to aging and should be taken into consideration in the design of bone substitutes. It is attributed that the developed HDPE/HA nano-composites could be a good alternative material for bone tissue regeneration due to their acceptable

[Use of pedicle percutaneous cemented screws in the management of patients with poor bone stock].

PubMed

Pesenti, S; Graillon, T; Mansouri, N; Adetchessi, T; Tropiano, P; Blondel, B; Fuentes, S

2016-12-01

Management of patients with poor bone stock remains difficult due to the risks of mechanical complications such as screws pullouts. At the same time, development of minimal invasive spinal techniques using a percutaneous approach is greatly adapted to these fragile patients with a reduction in operative time and complications. The aim of this study was to report our experience with cemented percutaneous screws in the management of patients with a poor bone stock. Thirty-five patients were included in this retrospective study. In each case, a percutaneous osteosynthesis using cemented screws was performed. Indications were osteoporotic fractures, metastasis or fractures on ankylosing spine. Depending on radiologic findings, short or long constructs (2 levels above and below) were performed and an anterior column support (kyphoplasty or anterior approach) was added. Evaluation of patients was based on pre and postoperative CT-scans associated with clinical follow-up with a minimum of 6 months. Eleven men and 24 women with a mean age of 73 years [60-87] were included in the study. Surgical indication was related to an osteoporotic fracture in 20 cases, a metastasis in 13 cases and a fracture on ankylosing spine in the last 2 cases. Most of the fractures were located between T10 and L2 and a long construct was performed in 22 cases. Percutaneous kyphoplasty was added in 24 cases and a complementary anterior approach in 3 cases. Average operative time was 86minutes [61-110] and blood loss was estimated as minor in all the cases. In the entire series, average volume of cement injected was 1.8 cc/screw. One patient underwent a major complication with a vascular leakage responsible for a cement pulmonary embolism. With a 9 months average follow-up [6-20], no cases of infection or mechanical complication was reported. Minimal invasive spinal techniques are greatly adapted to the management of fragile patients. The use of percutaneous cemented screws is, in our experience

Temperature measurement during polymerization of bone cement in percutaneous vertebroplasty: an in vivo study in humans.

PubMed

Anselmetti, Giovanni Carlo; Manca, Antonio; Kanika, Khanna; Murphy, Kieran; Eminefendic, Haris; Masala, Salvatore; Regge, Daniele

2009-05-01

Aim of the study was to "in vivo" measure temperature, during percutaneous vertebroplasty (PV), within a vertebral body injected with different bone cements. According to the declaration of Helsinki, 22 women (60-80 years; mean, 75 years) with painful osteoporotic vertebral collapse underwent bilateral transpedicular PV on 22 lumbar vertebrae. Two 10-G vertebroplasty needles were introduced into the vertebra under digital fluoroscopy; a 16-G radiofrequency thermoablation needle (Starburst XL; RITA Medical System Inc., USA), carrying five thermocouples, was than coaxially inserted. Eleven different bone cements were injected and temperatures were measured every 30 s until temperatures dropped under 45 degrees C. After the thermocouple needle was withdrawn, bilateral PV was completed with cement injection through the vertebroplasty needle. Unpaired Student's t-tests, Kruskal-Wallis test, and Wilcoxon signed rank test were used to evaluate significant differences (p < 0.05) in peak temperatures, variations between cements, and clinical outcome. All procedures were completed without complications, achieving good clinical outcomes (p < 0.0001). Regarding average peak temperature, cements were divided into three groups: A (over 60 degrees C), B (from 50 degrees to 60 degrees C), and C (below 50 degrees C). Peak temperature in Group A (86.7 +/- 10.7 degrees C) was significantly higher (p = 0.0172) than that in Groups B (60.5 +/- 3.7 degrees C) and C (44.8 +/- 2.6 degrees C). The average of all thermocouples showed an extremely significant difference (p = 0.0002) between groups. None of the tested cements maintained a temperature >or=45 degrees C for more than 30 min. These data suggest that back-pain improvement is obtained not by thermal necrosis but by mechanical consolidation only. The relative necrotic thermal effect in vertebral metastases seems to confirm that analgesia must be considered the main intent of PV.

Determination of bone and tissue concentrations of teicoplanin mixed with hydroxyapatite cement to repair cortical defects.

PubMed

Eggenreich, K; Zeipper, U; Schwendenwein, E; Hadju, S; Kaltenecker, G; Laslo, I; Lang, S; Roschger, P; Vecsei, V; Wintersteiger, R

2002-01-01

A highly specific and sensitive isocratic reversed-phase high performance liquid chromatography (HPLC) method for the determination of the major component of teicoplanin in tissue is reported. Comparing fluorescamine and o-phthalaldehyde (OPA) as derivatizing agents, the derivative formed with the latter exhibits superior fluorescence intensity allowing detection of femtomole quantities. Pretreatment for tissue samples is by solid-phase extraction which uses Bakerbond PolarP C(18) cartridges and gives effective clean up from endogenous by-products. Linearity was given from 0.6 to 100 ng per injection. The coefficient of variation did not exceed 5.8% for both interday and intraday assays. It was found that when bone defects are repaired with a hydroxyapatite-teicoplanin mixture, the antibiotic does not degrade, even when it is in the cement for several months. The stability of teicoplanin in bone cement was determined fluorodensitometrically.

Reconstruction of the Shallow Acetabulum With a Combination of Autologous Bulk and Impaction Bone Grafting Fixed by Cement.

PubMed

Maruyama, Masaaki; Wakabayashi, Shinji; Ota, Hiroshi; Tensho, Keiji

2017-02-01

Acetabular bone deficiency, especially proximal and lateral deficiency, is a difficult technical problem during primary total hip arthroplasty (THA) in developmental dysplasia of the hip (DDH). We report a new reconstruction method using a medial-reduced cemented socket and additional bulk bone in conjunction with impaction morselized bone grafting (additional bulk bone grafting method). In a population of patients with acetabular dysplasia undergoing THA using a medial-reduced cemented socket and additional bulk bone with impacted morselized bone grafting, we evaluated (1) the radiographic appearance of bone graft; (2) the proportion of cups that developed loosening and subsequent revision; and (3) clinical results (outcome scores and complications). Forty percent of 330 THAs for DDH performed at one center between 1999 and 2009 were defined as shallow dysplastic hips. The additional bulk bone grafting method was performed on 102 THAs with shallow acetabulum (31% for DDH) at one center between 1999 and 2009. We used this approach and technique for shallow acetabuli when a cup protruded from the lateral acetabular edge in preoperative templating. The other 132 dysplastic hips without bone grafting had THA performed at the same periods and served as a control. Acetabuli were defined as shallow when the depth was less than or equal to one-fifth of the pelvic height (cranial-caudal length on radiograph). The additional bulk bone grafting technique was as follows: the resected femoral head was sectioned at 1 to 2 cm thickness, and a suitable size of the bulk bone graft was placed on the lateral iliac cortex and fixed by poly-L-lactate absorbable screws. Autologous impaction morselized bone grafting, with or without hydroxyapatite granules, was performed along with the implantation of a medial-reduced cemented socket. We defined an "incorporated" graft as remodeling and trabeculation including rounding off of the protruding edge of a graft beyond the socket

Bone Repair and Military Readiness

DTIC Science & Technology

2013-10-19

prototype in animal models. By addressing the shortcomings of current PMMA bone cement, the development of the novel silorane bone cement will result in a...heat generation. We have developed a silorane based resin superior to polymethyl methacrylate ( PMMA ) with many improved properties such as significantly...treatment of patients. By addressing the shortcomings of current PMMA bone cement, the development of the novel silorane bone cement will result in a

Reconstruction of chest wall using a two-layer prolene mesh and bone cement sandwich.

PubMed

Aghajanzadeh, Manouchehr; Alavi, Ali; Aghajanzadeh, Gilda; Ebrahimi, Hannan; Jahromi, Sina Khajeh; Massahnia, Sara

2015-02-01

Wide surgical resection is the most effective treatment for the vast majority of chest wall tumors. This study evaluated the clinical success of chest wall reconstruction using a Prolene mesh and bone cement prosthetic sandwich. The records of all patients undergoing chest wall resection and reconstruction were reviewed. Surgical indications, the location and size of the chest wall defect, diaphragm resection, pulmonary performance, postoperative complications, and survival of each patient were recorded. From 1998 to 2008, 43 patients (27 male, 16 female; mean age of 48 years) underwent surgery in our department to treat malignant chest wall tumors: chondrosarcoma (23), osteosarcoma (8), spindle cell sarcoma (6), Ewing's sarcoma (2), and others (4). Nine sternectomies and 34 antero-lateral and postero-lateral chest wall resections were performed. Postoperatively, nine patients experienced respiratory complications, and one patient died because of respiratory failure. The overall 4-year survival rate was 60 %. Chest wall reconstruction using a Prolene mesh and bone cement prosthetic sandwich is a safe and effective surgical procedure for major chest wall defects.

Results of cement augmentation and curettage in aneurysmal bone cyst of spine

PubMed Central

Basu, Saumyajit; Patel, Dharmesh R; Dhakal, Gaurav; Sarangi, T

2016-01-01

Aneurysmal bone cyst (ABC) is a vascular tumor of the spine. Management of spinal ABC still remains controversial because of its location, vascular nature and incidence of recurrence. In this manuscript, we hereby describe two cases of ABC spine treated by curettage, vertebral cement augmentation for control of bleeding and internal stabilization with two years followup. To the best of our knowledge, this is the first case report in the literature describing the role of cement augmentation in spinal ABC in controlling vascular bleeding in curettage of ABC of spine. Case 1: A 22 year old male patient presented with chronic back pain. On radiological investigation, there were multiple, osteolytic septite lesions at L3 vertebral body without neural compression or instability. Percutaneous transpedicular biopsy of L3 from involved pedicle was done. This was followed by cement augmentation through the uninvolved pedicle. Next, transpedicular complete curettage was done through involved pedicle. Case 2: A 15-year-old female presented with nonradiating back pain and progressive myelopathy. On radiological investigation, there was an osteolytic lesion at D9. At surgery, decompression, pedicle screw-rod fixation and posterolateral fusion from D7 to D11 was done. At D9 level, through normal pedicle cement augmentation was added to provide anterior column support and to control the expected bleeding following curettage. Transpedicular complete curettage was done through the involved pedicle with controlled bleeding at the surgical field. Cement augmentation was providing controlled bleeding at surgical field during curettage, internal stabilization and control of pain. On 2 years followup, pain was relieved and there was a stable spinal segment with well filled cement without any sign of recurrence in computed tomography scan. In selected cases of spinal ABC with single vertebral, single pedicle involvement; cement augmentation of vertebra through normal pedicle has an

pHEMA-nHA encapsulation and delivery of vancomycin and rhBMP-2 enhances its role as a bone graft substitute.

PubMed

Li, Xinning; Xu, Jianwen; Filion, Tera M; Ayers, David C; Song, Jie

2013-08-01

Bone grafts are widely used in orthopaedic procedures. Autografts are limited by donor site morbidity while allografts are known for considerable infection and failure rates. A synthetic composite bone graft substitute poly(2-hydroxyethyl methacrylate)-nanocrystalline hydroxyapatite (pHEMA-nHA) was previously developed to stably press-fit in and functionally repair critical-sized rat femoral segmental defects when it was preabsorbed with a single low dose of 300 ng recombinant human bone morphogenetic protein-2/7 (rhBMP-2/7). To facilitate clinical translation of pHEMA-nHA as a synthetic structural bone graft substitute, we examined its ability to encapsulate and release rhBMP-2 and the antibiotic vancomycin. We analyzed the compressive behavior and microstructure of pHEMA-nHA as a function of vancomycin incorporation doses using a dynamic mechanical analyzer and a scanning electron microscope. In vitro release of vancomycin was monitored by ultraviolet-visible spectroscopy. Release of rhBMP-2 from pHEMA-nHA-vancomycin was determined by ELISA. Bioactivity of the released vancomycin and rhBMP-2 was examined by bacterial inhibition and osteogenic transdifferentiation capabilities in cell culture, respectively. Up to 4.8 wt% of vancomycin was incorporated into pHEMA-nHA without compromising its structural integrity and compressive modulus. Encapsulated vancomycin was released in a dose-dependent and sustained manner in phosphate-buffered saline over 2 weeks, and the released vancomycin inhibited Escherichia coli culture. The pHEMA-nHA-vancomycin composite released preabsorbed rhBMP-2 in a sustained manner over 8 days and locally induced osteogenic transdifferentiation of C2C12 cells in culture. pHEMA-nHA can encapsulate and deliver vancomycin and rhBMP-2 in a sustained and localized manner with reduced loading doses. The elasticity, osteoconductivity, and rhBMP-2/vancomycin delivery characteristics of pHEMA-nHA may benefit orthopaedic reconstructions or fusions with

[Bone cement implant as an alternative for orbital floor reconstruction: A case report].

PubMed

Vargas-Solalinde, Enrique; Huichapa-Padilla, Marisol E; Garza-Cantú, Daniel; Reyna-Martínez, Víctor H; Alatorre-Ricardo, Julio; González-Treviño, Juan Luis

2017-12-01

The management of orbitary fractures is one of the most challenging in facial trauma; the variety of reconstruction materials for its treatment is broad and is constantly improving, but despite this there is no consensus for its use or literature that sustains it. To present the use and design of a preformed bone implant as an alternative for the reconstruction of orbital floor fractures in the pediatric age group. A 7-year old male who suffered a right hemifacial contusion trauma with clinical and tomographic diagnosis of right pure blowout type orbital floor fracture with inferior rectus muscle entrapment and right post-traumatic palpebral ptosis. Successful surgical reconstruction was performed 7 days later with a pre-constructed bone cement implant. Eight weeks after surgery the patient presented with mild residual palpebral ptosis, no ocular movement limitations and no diplopia. The use of a bone cement implant can be considered appropriate for the reconstruction of these fractures, as another alternative to be used by the ophthalmologist among the variety of all the other materials used for this purpose. We consider that our optimism based on the results obtained in this case obligates us to increase the number of patients treated in order to gather more evidence and do larger follow up. Copyright © 2016 Academia Mexicana de Cirugía A.C. Publicado por Masson Doyma México S.A. All rights reserved.

Phosphoserine-modified calcium phosphate cements: bioresorption and substitution.

PubMed

Offer, Liliana; Veigel, Bastian; Pavlidis, Theodoros; Heiss, Christian; Gelinsky, Michael; Reinstorf, Antje; Wenisch, Sabine; Lips, Katrin Susanne; Schnettler, Reinhard

2011-01-01

This work reports the effects of phosphoserine addition on the biodegradability of calcium phosphate cements. The characteristics of a phosphoserine-modified calcium phosphate cement without collagen in a large animal model are presented here for the first time. Critical size bone defects in the proximal tibia of 10 sheep were filled with the bone cement, and five sheep with empty defects were included as controls. The sheep were sacrificed after either 10 days or 12 weeks, and bones were processed for histological, histomorphometric and enzyme histochemical analyses as well as transmission electron microscopic examination. After 12 weeks, there was no significant reduction in either the implant or the bone defect cross-sectional area. Different amounts of fibrous tissue were observed around the implant and in the bone defect after 12 weeks. The direct bone-implant contact decreased after 12 weeks (p = 0.034). Although the implanted material properly filled the defect and promoted an initial activation of macrophages and osteoblasts, the resorption and simultaneous substitution did not reach expected levels during the experimental time course. Although other studies have shown that the addition of phosphoserine to calcium phosphate cements that have already been modified with collagen I resulted in an acceleration of cement resorption and bone regeneration, this study demonstrates that phosphoserine-modified calcium phosphate cements without collagen perform poorly in the treatment of bone defects. Efforts to use phosphoserine in the development of new composites should take into consideration the need to improve osteoconduction simultaneously via other means. Copyright © 2010 John Wiley & Sons, Ltd.

Real-time synchronous measurement of curing characteristics and polymerization stress in bone cements with a cantilever-beam based instrument

NASA Astrophysics Data System (ADS)

Palagummi, Sri Vikram; Landis, Forrest A.; Chiang, Martin Y. M.

2018-03-01

An instrumentation capable of simultaneously determining degree of conversion (DC), polymerization stress (PS), and polymerization exotherm (PE) in real time was introduced to self-curing bone cements. This comprises the combination of an in situ high-speed near-infrared spectrometer, a cantilever-beam instrument with compliance-variable feature, and a microprobe thermocouple. Two polymethylmethacrylate-based commercial bone cements, containing essentially the same raw materials but differ in their viscosity for orthopedic applications, were used to demonstrate the applicability of the instrumentation. The results show that for both the cements studied the final DC was marginally different, the final PS was different at the low compliance, the peak of the PE was similar, and their polymerization rates were significantly different. Systematic variation of instrumental compliance for testing reveals differences in the characteristics of PS profiles of both the cements. This emphasizes the importance of instrumental compliance in obtaining an accurate understanding of PS evaluation. Finally, the key advantage for the simultaneous measurements is that these polymerization properties can be correlated directly, thus providing higher measurement confidence and enables a more in-depth understanding of the network formation process.

The combination of ultrasound with antibiotics released from bone cement decreases the viability of planktonic and biofilm bacteria: an in vitro study with clinical strains.

PubMed

Ensing, Geert T; Neut, Daniëlle; van Horn, Jim R; van der Mei, Henny C; Busscher, Henk J

2006-12-01

Antibiotic-loaded bone cements are used for the permanent fixation of joint prostheses. Antibiotic-loaded cements significantly decrease the incidence of infection. The objective of this study was to investigate whether the viability of bacteria derived from patients with a prosthesis-related infection could be further decreased when antibiotic release from bone cements was combined with application of pulsed ultrasound. Escherichia coli ATCC 10798, Staphylococcus aureus 7323, coagulase-negative staphylococci (CoNS 7368 and CoNS 7391) and Pseudomonas aeruginosa 5148 were grown planktonically in suspension and as a biofilm on three different bone cements: Palacos R without gentamicin as control, gentamicin-loaded Palacos R-G and gentamicin/clindamycin-loaded Copal. The viability of planktonic and biofilm bacteria was measured in the absence and presence of pulsed ultrasound for 40 h. Ultrasound itself did not affect bacterial viability. However, application of pulsed ultrasound in combination with antibiotic release by antibiotic-loaded bone cements yielded a reduction of both planktonic and biofilm bacterial viability compared with antibiotic release without application of ultrasound. This study shows that antibiotic release in combination with ultrasound increases the antimicrobial efficacy further than antibiotic release alone against a variety of clinical isolates. Application of ultrasound in combination with antibiotic release in clinical practice could therefore lead to better prevention or treatment of prosthesis-related infections.

A new acoustic method to determine the setting time of calcium sulfate bone cement mixed with antibiotics.

PubMed

Cooper, J J; Brayford, M J; Laycock, P A

2014-08-01

A new method is described which can be used to determine the setting times of small amounts of high value bone cements. The test was developed to measure how the setting times of a commercially available synthetic calcium sulfate cement (Stimulan, Biocomposites, UK) in two forms (standard and Rapid Cure) varies with the addition of clinically relevant antibiotics. The importance of being able to accurately quantify these setting times is discussed. The results demonstrate that this new method, which is shown to correlate to the Vicat needle, gives reliable and repeatable data with additional benefits expressed in the article. The majority of antibiotics mixed were found to retard the setting reaction of the calcium sulfate cement.

The Primary Stability of a Bioabsorbable Poly-L-Lactic Acid Suture Anchor for Rotator Cuff Repair Is Not Improved with Polymethylmethacrylate or Bioabsorbable Bone Cement Augmentation.

PubMed

Güleçyüz, Mehmet F; Kraus-Petersen, Michael; Schröder, Christian; Ficklscherer, Andreas; Wagenhäuser, Markus U; Braun, Christian; Müller, Peter E; Pietschmann, Matthias F

2018-02-01

The incidence of osteoporosis and rotator cuff tears increases with age. Cement augmentation of bones is an established method in orthopedic and trauma surgery. This study analyses if polymethylmethacrylate or bioabsorbable cement can improve the primary stability of a bioabsorbable suture anchor in vitro in comparison to a non-augmented suture anchor in osteoporotic human humeri. The trabecular bone mineral density was measured to ensure osteopenic human specimens. Then the poly-l-lactic acid Bio-Corkscrew® FT was implanted in the greater tuberosity footprint with polymethylmethacrylate Refobacin® cement augmentation ( n  = 8), with Cerament™ Bone Void Filler augmentation ( n  = 8) and without augmentation ( n  = 8). Using a cyclic testing protocol, the failure loads, system displacement, and failure modes were recorded. The Cerament™ augmented Bio-Corkscrew® FT yielded the highest failure loads (206.7 N), followed by polymethylmethacrylate Refobacin® augmentation (206.1 N) and without augmentation (160.0 N). The system displacement was lowest for Cerament™ augmentation (0.72 mm), followed by polymethylmethacrylate (0.82 mm) and without augmentation (1.50 mm). Statistical analysis showed no significant differences regarding the maximum failure loads ( p  = 0.1644) or system displacement ( p  = 0.4199). The main mode of failure for all three groups was suture slippage. The primary stability of the Bio-Corkscrew® FT is not influenced by bone cement augmentation with polymethylmethacrylate Refobacin® or with bioabsorbable Cerament™ in comparison to the non-cemented anchors. The cement augmentation of rotator cuff suture anchors in osteoporotic bones remains questionable since biomechanical tests show no significant advantage.

Temperature Measurement During Polymerization of Bone Cement in Percutaneous Vertebroplasty: An In Vivo Study in Humans

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anselmetti, Giovanni Carlo, E-mail: giovanni.anselmetti@ircc.it; Manca, Antonio; Kanika, Khanna

2009-05-15

Aim of the study was to 'in vivo' measure temperature, during percutaneous vertebroplasty (PV), within a vertebral body injected with different bone cements. According to the declaration of Helsinki, 22 women (60-80 years; mean, 75 years) with painful osteoporotic vertebral collapse underwent bilateral transpedicular PV on 22 lumbar vertebrae. Two 10-G vertebroplasty needles were introduced into the vertebra under digital fluoroscopy; a 16-G radiofrequency thermoablation needle (Starburst XL; RITA Medical System Inc., USA), carrying five thermocouples, was than coaxially inserted. Eleven different bone cements were injected and temperatures were measured every 30 s until temperatures dropped under 45{sup o}C. Aftermore » the thermocouple needle was withdrawn, bilateral PV was completed with cement injection through the vertebroplasty needle. Unpaired Student's t-tests, Kruskal-Wallis test, and Wilcoxon signed rank test were used to evaluate significant differences (p < 0.05) in peak temperatures, variations between cements, and clinical outcome. All procedures were completed without complications, achieving good clinical outcomes (p < 0.0001). Regarding average peak temperature, cements were divided into three groups: A (over 60{sup o}C), B (from 50{sup o} to 60{sup o}C), and C (below 50{sup o}C). Peak temperature in Group A (86.7 {+-} 10.7{sup o}C) was significantly higher (p = 0.0172) than that in Groups B (60.5 {+-} 3.7{sup o}C) and C (44.8 {+-} 2.6{sup o}C). The average of all thermocouples showed an extremely significant difference (p = 0.0002) between groups. None of the tested cements maintained a temperature {>=}45{sup o}C for more than 30 min. These data suggest that back-pain improvement is obtained not by thermal necrosis but by mechanical consolidation only. The relative necrotic thermal effect in vertebral metastases seems to confirm that analgesia must be considered the main intent of PV.« less

In vivo evaluation of teicoplanin- and calcium sulfate-loaded PMMA bone cement in preventing implant-related osteomyelitis in rats.

PubMed

Tuzuner, T; Sencan, I; Ozdemir, D; Alper, M; Duman, S; Yavuz, T; Yildirim, M

2006-12-01

The objective of this study was to evaluate the efficacy of teicoplanin- and calcium sulphate-loaded polymethylmethacrylate (PMMA) bone cements in preventing experimental implant-related osteomyelitis in rats. Four groups of antibiotic-loaded rods were prepared and were implanted into the lateral condylus of the rat femur after inoculation of Staphylococcus aureus. The effectiveness of these were assessed microbiologically, radiographically, and histopathologically. Radiographic evaluation revealed a significant reduction of periostal reaction and osteolysis in rats that received calcium sulphate- and teicoplanin-loaded rods. Histopathological evaluation confirmed these results. Acute infection and bone necrosis were found to be significantly lower in rats that had received calcium sulphate- and teicoplanin-loaded rods. The addition of calcium sulfate to teicoplanin-loaded PMMA bone cement appeared satisfactory as an antibiotic-carrying system for prophylaxis of experimental implant-related osteomyelitis, but further investigations are needed to reach definitive statements for clinical applications.

Effect of the calcium to phosphorus ratio on the setting properties of calcium phosphate bone cements.

PubMed

Vlad, M D; Gómez, S; Barracó, M; López, J; Fernández, E

2012-09-01

α-Tricalcium phosphate (α-TCP) has become the main reactant of most experimental and commercial ceramic bone cements. It has calcium-to-phosphorus (Ca/P) ratio of 1.50. The present study expands and reports on the microstructures and mechanical properties of calcium phosphate (CP) cements containing sintered monolithic reactants obtained in the interval 1.29 < Ca/P < 1.77. The study focuses on their cement setting and hardening properties as well as on their microstructure and crystal phase evolution. The results showed that: (a) CP-cements made with reactants with Ca/P ratio other than 1.50 have longer setting and lower hardening properties; (b) CP-cements reactivity was clearly affected by the Ca/P ratio of the starting reactant; (c) reactants with Ca/P < 1.50 were composed of several phases, calcium pyrophosphate and α- and β-TCP. Similarly, reactants with Ca/P > 1.50 were composed of α-TCP, tetracalcium phosphate and hydroxyapatite; (d) only the reactant with Ca/P = 1.50 was monophasic and was made of α-TCP, which transformed during the setting into calcium deficient hydroxyapatite; (e) CP-cements developed different crystal microstructures with specific features depending on the Ca/P ratio of the starting reactant.

Cement Leakage in Percutaneous Vertebral Augmentation for Osteoporotic Vertebral Compression Fractures: Analysis of Risk Factors.

PubMed

Xie, Weixing; Jin, Daxiang; Ma, Hui; Ding, Jinyong; Xu, Jixi; Zhang, Shuncong; Liang, De

2016-05-01

The risk factors for cement leakage were retrospectively reviewed in 192 patients who underwent percutaneous vertebral augmentation (PVA). To discuss the factors related to the cement leakage in PVA procedure for the treatment of osteoporotic vertebral compression fractures. PVA is widely applied for the treatment of osteoporotic vertebral fractures. Cement leakage is a major complication of this procedure. The risk factors for cement leakage were controversial. A retrospective review of 192 patients who underwent PVA was conducted. The following data were recorded: age, sex, bone density, number of fractured vertebrae before surgery, number of treated vertebrae, severity of the treated vertebrae, operative approach, volume of injected bone cement, preoperative vertebral compression ratio, preoperative local kyphosis angle, intraosseous clefts, preoperative vertebral cortical bone defect, and ratio and type of cement leakage. To study the correlation between each factor and cement leakage ratio, bivariate regression analysis was employed to perform univariate analysis, whereas multivariate linear regression analysis was employed to perform multivariate analysis. The study included 192 patients (282 treated vertebrae), and cement leakage occurred in 100 vertebrae (35.46%). The vertebrae with preoperative cortical bone defects generally exhibited higher cement leakage ratio, and the leakage is typically type C. Vertebrae with intact cortical bones before the procedure tend to experience type S leakage. Univariate analysis showed that patient age, bone density, number of fractured vertebrae before surgery, and vertebral cortical bone were associated with cement leakage ratio (P<0.05). Multivariate analysis showed that the main factors influencing bone cement leakage are bone density and vertebral cortical bone defect, with standardized partial regression coefficients of -0.085 and 0.144, respectively. High bone density and vertebral cortical bone defect are

21 CFR 888.4200 - Cement dispenser.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Cement dispenser. 888.4200 Section 888.4200 Food... DEVICES ORTHOPEDIC DEVICES Surgical Devices § 888.4200 Cement dispenser. (a) Identification. A cement dispenser is a nonpowered syringe-like device intended for use in placing bone cement (§ 888.3027) into...

21 CFR 888.4200 - Cement dispenser.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Cement dispenser. 888.4200 Section 888.4200 Food... DEVICES ORTHOPEDIC DEVICES Surgical Devices § 888.4200 Cement dispenser. (a) Identification. A cement dispenser is a nonpowered syringe-like device intended for use in placing bone cement (§ 888.3027) into...

21 CFR 888.4200 - Cement dispenser.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Cement dispenser. 888.4200 Section 888.4200 Food... DEVICES ORTHOPEDIC DEVICES Surgical Devices § 888.4200 Cement dispenser. (a) Identification. A cement dispenser is a nonpowered syringe-like device intended for use in placing bone cement (§ 888.3027) into...

21 CFR 888.4200 - Cement dispenser.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Cement dispenser. 888.4200 Section 888.4200 Food... DEVICES ORTHOPEDIC DEVICES Surgical Devices § 888.4200 Cement dispenser. (a) Identification. A cement dispenser is a nonpowered syringe-like device intended for use in placing bone cement (§ 888.3027) into...

21 CFR 888.4200 - Cement dispenser.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cement dispenser. 888.4200 Section 888.4200 Food... DEVICES ORTHOPEDIC DEVICES Surgical Devices § 888.4200 Cement dispenser. (a) Identification. A cement dispenser is a nonpowered syringe-like device intended for use in placing bone cement (§ 888.3027) into...

Microencapsulation of 2-octylcyanoacrylate tissue adhesive for self-healing acrylic bone cement.

PubMed

Brochu, Alice B W; Chyan, William J; Reichert, William M

2012-10-01

Here, we report the first phase of developing self-healing acrylic bone cement: the preparation and characterization of polyurethane (PUR) microcapsules containing a medical cyanoacrylate tissue adhesive. Capsules were prepared by interfacial polymerization of a toluene-2,4-diisocyanate-based polyurethane prepolymer with 1,4-butanediol to encapsulate 2-octylcyanoacrylate (OCA). Various capsule characteristics, including: resultant morphology, average size and size distribution, shell thickness, content and reactivity of encapsulated agent, and shelf life are investigated and their reliance on solvent type and amount, surfactant type and amount, temperature, pH, agitation rate, reaction time, and mode of addition of the oil phase to the aqueous phase are presented. Capsules had average diameters ranging from 74 to 222 μm and average shell thicknesses ranging from 1.5 to 6 μm. The capsule content was determined via thermogravimetric analysis and subsequent analysis of the capsules following up to 8 weeks storage revealed minimal loss of core contents. Mechanical testing of OCA-containing capsules showed individual capsules withstood compressive forces up to a few tenths of Newtons, and the contents released from crushed capsules generated tensile adhesive forces of a few Newtons. Capsules were successfully mixed into the poly(methyl methacrylate) bone cement, surviving the mixing process, exposure to methyl methacrylate monomer, and the resulting exothermic matrix curing. Copyright © 2012 Wiley Periodicals, Inc.

Anti-inflammation performance of curcumin-loaded mesoporous calcium silicate cement.

PubMed

Chen, Yuan-Chien; Shie, Ming-You; Wu, Yuan-Haw Andrew; Lee, Kai-Xing Alvin; Wei, Li-Ju; Shen, Yu-Fang

2017-09-01

Calcium silicate (CS) cements have excellent bioactivity and can induce the bone-like apatite formation. They are good biomaterials for bone tissue engineering and bone regenerative medicine. However, they have degradability and the dissolved CS can cause the inflammatory response at the early post-implantation stage. The purpose of this study was to design and prepare the curcumin-loaded mesoporous CS (MesoCS/curcumin) cements as a strategy to reduce the inflammatory reaction after implantation. The MesoCS/curcumin cements were designed and prepared. The characteristics of MesoCS/curcumin specimens were examined by transmission electron microscopy (TEM), X-ray diffraction (XRD) and scanning electron microscopy (SEM). Their physical properties, biocompatibility, and anti-inflammatory ability were also evaluated. The MesoCS/curcumin cements displayed excellent biocompatibility and physical properties. Their crystalline characterizations were very similar with MesoCS cements. After soaking in simulated body fluid, the bone-like apatite layer of the MesoCS/curcumin cements could be formed. In addition, it could inhibit the expression of tumor necrosis factor-α (TNF-α) and interleukin-1 (IL-1) after inflammation reaction induced by lipopolysaccharides and had good anti-inflammatory ability. Adding curcumin in MesoCS cements can reduce the inflammatory reaction, but does not affect the original biological activity and properties of MesoCS cements. It can provide a good strategy to inhibit the inflammatory reaction after implantation for bone tissue engineering and bone regenerative medicine. Copyright © 2017. Published by Elsevier B.V.

Investigation of bone formation using calcium phosphate glass cement in beagle dogs

PubMed Central

Lee, Seung-Bum; Jung, Ui-Won; Choi, Youna; Jamiyandorj, Otgonbold; Kim, Chang-Sung; Lee, Yong-Keun; Chai, Jung-Kiu

2010-01-01

Purpose Among available biomaterials, bioceramics have drawn special interest due to their bioactivity and the possibility of tailoring their composition. The degradation rate and formulation of bioceramics can be altered to mimic the compositions of the mineral phase of bone. The aim of this study was to investigate the bone formation effect of amorphous calcium phosphate glass cement (CPGC) synthesized by a melting and quenching process. Methods In five male beagle dogs, 4 × 4 mm 1-wall intrabony defects were created bilaterally at the mesial or distal aspect of the mandibular second and fourth premolars. Each of the four defects was divided according to graft materials: CPGC with collagen membrane (CM), biphasic calcium phosphate (BCP) with CM, CM alone, or a surgical flap operation only. The dogs were sacrificed 8 weeks post-surgery, and block sections of the defects were collected for histologic and histometric analysis. Results There were significant differences in bone formation and cementum regeneration between the experimental and control groups. In particular, the CPGC and BCP groups showed greater bone formation than the CM and control groups. Conclusions In conclusion, CPGC was replaced rapidly with an abundant volume of new bone; CPGC also contributed slightly to regeneration of the periodontal apparatus. PMID:20607057

The mechanical and biological studies of calcium phosphate cement-fibrin glue for bone reconstruction of rabbit femoral defects

PubMed Central

Dong, Jingjing; Cui, Geng; Bi, Long; Li, Jie; Lei, Wei

2013-01-01

In order to improve the mechanical and biological properties of calcium phosphate cement (CPC, nanometer-biomaterial) for bone reconstruction in the rabbit femoral defect model, fibrin glue (FG, the natural product, purified from the blood) was introduced at three different ratios. The CPC powder and the FG solution were mixed, respectively, at the powder/liquid (P/L) ratios (g/mL) of 1:1, 3:1, and 5:1 (g/mL), and pure CPC was used as a control. After being implanted into the femoral defect in rabbit, the healing process was evaluated by micro-computed tomography scan, biomechanical testing, and histological examination. By micro-computed tomography analysis, the P/L ratio of 1:1 (g/mL) group indicated the largest quantity of new bone formation at 4 weeks, 8 weeks, and 12 weeks after implantation, respectively. Bone volume per trabecular volume of the 1:1 group was highest in the four groups, which was 1.45% ± 0.42%, 7.35% ± 1.45%, and 29.10% ± 1.67% at 4 weeks, 8 weeks, and 12 weeks after the operation, respectively. In the biomechanical tests, the compressive strength and the elastic modulus of the three CPC–FG groups were much higher than those of the pure CPC group at the determined time point (P < 0.05). The histological evaluation also showed the best osseointegration in the 1:1 group at 4 weeks, 8 weeks, and 12 weeks after the operation, respectively. In the 1:1 group, the bone grew into the pore of the cement in the laminar arrangement and connected with the cement tightly at the 12th week after the operation. This present study indicated that the CPC–FG composite at the P/L ratio of 1:1 (g/mL) stimulated bone regeneration better than any other designed group, which suggested that CPC–FG at the P/L ratio of 1:1 has significant potential as the bioactive material for the treatment of bone defects. PMID:23576869

In vitro adhesion and biocompatability of osteoblast-like cells to poly(methylmethacrylate) and poly(ethylmethacrylate) bone cements.

PubMed

Dalby, M J; Di Silvio, L; Harper, E J; Bonfield, W

2002-03-01

A bone cement, poly(ethylmethacrylate)/n-butylmethacrylate (PEMA/nBMA) has been developed with lower exotherm and monomer leaching compared to the traditional poly(methylmethacrylate)/methylmethacrylate (PMMA/MMA) cement. This study compares the in vitro biological response to the cements using primary human osteoblast-like cells (HOB). Cell attachment was qualified by immunolocalization of vinculin and actin cytoskeleton, showing more organization on PEMA/nBMA compared to PMMA/MMA. Proliferation was assessed using tritiated thymidine incorporation, and phenotype expression determined by measuring alkaline phosphatase (ALP) activity. An increase in proliferation and ALP activity was observed on PEMA/nBMA compared to PMMA/MMA. The results confirm the biocompatability of PEMA/nBMA, and an enhanced cell attachment and expression of differentiated cell phenotype.

Elution kinetics, antimicrobial activity, and mechanical properties of 11 different antibiotic loaded acrylic bone cement.

PubMed

Gálvez-López, Ruben; Peña-Monje, Alejandro; Antelo-Lorenzo, Ramón; Guardia-Olmedo, Juan; Moliz, Juan; Hernández-Quero, José; Parra-Ruiz, Jorge

2014-01-01

Antibiotic-loaded acrylic bone cements (ALABC) spacers are routinely used in the treatment of prosthetic joint infections. The objectives of our study were to evaluate different ALABC for elution kinetics, thermal stability, and mechanical properties. A 10 or 20% mixture (w/w) beads of medium viscosity bone cement (DePuy, Inc) and vancomycin (VAN), gentamycin (GM), daptomycin (DAP), moxifloxacin (MOX), rifampicin (RIF), cefotaxime (CTX), cefepime (FEP), amoxicillin clavulanate (AmC), ampicillin (AMP), meropenem (MER), and ertapenem (ERT) were formed and placed into wells filled with phosphate-buffered saline. Antibiotic concentrations were determined using high-performance liquid chromatography. Antimicrobial activity was tested against Micrococcus luteus ATCC 9341 or Escherichia coli ATCC 25922. AmC, AMP, and FEP concentration rapidly decreased after day 2, being almost undetectable at day 4. Sustained and high elution rates were observed with VAN, GM, MOX, and RIF for the 30-day duration of the experiment. DAP, MER, ERT, and CTX elution rates constantly decreased from day 4. All antibiotics tested retained antimicrobial activity proving thermal stability. Mechanical properties of ALABC were maintained except when RIF was used. © 2013.

Micro-stereotactic frame utilizing bone cement for individual fabrication: an initial investigation of its accuracy

NASA Astrophysics Data System (ADS)

Rau, Thomas S.; Lexow, G. Jakob; Blume, Denise; Kluge, Marcel; Lenarz, Thomas; Majdani, Omid

2017-03-01

A new method for template-guided cochlear implantation surgery is proposed which has been developed to create a minimally invasive access to the inner ear. A first design of the surgical template was drafted, built, and finally tested regarding its accuracy. For individual finalization of the micro-stereotactic frame bone cement is utilized as this well-known and well-established material suggests ease of use as well as high clinical acceptance and enables both sterile and rapid handling. The new concept includes an alignment device, based on a passive hexapod with manually adjustable legs for temporary fixation of the separate parts in the patient-specific pose until the bone cement is spread and finally cured. Additionally, a corresponding evaluation method was developed to determine the accuracy of the microstereotactic frame in some initial experiments. In total 18 samples of the surgical template were fabricated based on previously planned trajectories. The mean positioning error at the target point was 0.30 mm with a standard deviation of 0.25 mm.

Theoretical prediction and experimental determination of the effect of mold characteristics on temperature and monomer conversion fraction profiles during polymerization of a PMMA-based bone cement.

PubMed

Vallo, Claudia I

2002-01-01

The present work is concerned with applications of a kinetic model for free-radical polymerization of a polymethylmethacrylate-based bone cement. Autocatalytic behavior at the first part of the reaction as well as a diffusion control phenomenon near vitrification are described by the model. Comparison of theoretical computations with experimental measurements for the temperature evolution during batch casting demonstrated the capacity of the proposed model to represent the kinetic behavior of the polymerization reaction. Temperature evolution and monomer conversion were simulated for the cure of the cement in molds made of different materials. The maximum monomer conversion fraction was markedly influenced by the physical properties of the mold material. The unreacted monomer acts as a plasticizer that influences the mechanical behavior of the cement. Hence, the same cement formulation cured in molds of different materials may result in different mechanical response because of the differences in the amounts of residual monomer. Standardization of the mold type to prepare specimens for the mechanical characterization of bone cements is recommended. Theoretical prediction of temperature evolution during hip replacement indicated that for cement thickness lower than 6 mm the peak temperature at the bone-cement interface was below the limit stated for thermal injury (50 degrees C for more than 1 min). The use of thin cement layers is recommended to diminish the risk of thermal injury; however, it is accompanied by an increase in the amount of unreacted monomer present in the cured material. Copyright 2002 Wiley Periodicals, Inc. J Biomed Mater Res (Appl Biomater) 63: 627-642, 2002

The influence of nano MgO and BaSO4 particle size additives on properties of PMMA bone cement.

PubMed

Ricker, Alyssa; Liu-Snyder, Peishan; Webster, Thomas J

2008-01-01

A common technique to aid in implant fixation into surrounding bone is to inject bone cement into the space between the implant and surrounding bone. The most common bone cement material used clinically today is poly(methyl methacrylate), or PMMA. Although promising, there are numerous disadvantages of using PMMA in bone fixation applications which has limited its wide spread use. Specifically, the PMMA polymerization reaction is highly exothermic in situ, thus, damaging surrounding bone tissue while curing. In addition, PMMA by itself is not visible using typical medical imaging techniques (such as X-rays required to assess new bone formation surrounding the implant). Lastly, although PMMA does support new bone growth, studies have highlighted decreased osteoblast (bone forming cell) functions on PMMA compared to other common orthopedic coating materials, such as calcium phosphates and hydroxyapatite. For these reasons, the goal of this study was to begin to investigate novel additives to PMMA which can enhance its cytocompatibility properties with osteoblasts, decrease its exothermic reaction when curing, and increase its radiopacity. Results of this study demonstrated that compared to conventional (or micron) equivalents, PMMA with nanoparticles of MgO and BaSO4 reduced harmful exothermic reactions of PMMA during solidification and increased radiopacity, respectively. Moreover, osteoblast adhesion increased on PMMA with nanoparticles of MgO and BaSO4 compared with PMMA alone. This study, thus, suggests that nanoparticles of MgO and BaSO4 should be further studied for improving properties of PMMA for orthopedic applications.

Response of human bone marrow-derived MSCs on triphasic Ca-P substrate with various HA/TCP ratio.

PubMed

Bajpai, Indu; Kim, Duk Yeon; Kyong-Jin, Jung; Song, In-Hwan; Kim, Sukyoung

2017-01-01

Calcium phosphates (Ca-P) are used commonly as artificial bone substitutes to control the biodegradation rate of an implant in the body fluid. This study examined the in vitro proliferation of human bone marrow-derived mesenchymal stem cells (hBMSCs) on triphasic Ca-P samples. For this aspect, hydroxyapatite (HA), dicalcium phosphate dehydrate (DCPD), and calcium hydroxide (Ca(OH) 2 ) were mixed at various ratios, cold compacted, and sintered at 1250°C in air. X-ray diffraction showed that the β-tricalcium phosphate (TCP) to α-TCP phase transformation increased with increasing DCPD/HA ratio. The micro-hardness deceased with increasing TCP content, whereas the mean grain size and porosity increased with increasing TCP concentration. To evaluate the in vitro degree of adhesion and proliferation on the HA/TCP samples, human BMSCs were incubated on the HA/TCP samples and analyzed by a cells proliferation assay, expression of the extracellular matrix (ECM) genes, such as α-smooth muscle actin (α-SMA) and fibronectin (FN), and FITC-phalloidin fluorescent staining. In terms of the interactions of human BMSCs with the triphasic Ca-P samples, H50T50 (Ca/P = 1.59) markedly enhanced cell spreading, proliferation, FN, and α-SMA compared with H100T0 (Ca/P = 1.67). Interestingly, these results show that among the five HA/TCP samples, H50T50 is the optimal Ca-P composition for in vitro cell proliferation. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 72-80, 2017. © 2015 Wiley Periodicals, Inc.

Osteogenic properties of PBLG-g-HA/PLLA nanocomposites.

PubMed

Liao, Lan; Yang, Shuang; Miron, Richard J; Wei, Junchao; Zhang, Yufeng; Zhang, Meng

2014-01-01

New development of biomaterial scaffolds remains a prominent issue for the regeneration of lost or fractured bone. Of these scaffolds, a number of bioactive polymers have been synthesized and fabricated for diverse biological roles. Although recent evidence has demonstrated that composite scaffolds such as HA/PLLA have improved properties when compared to either HA or PLLA alone, recent investigations have demonstrated that the phase compatibility between HA and PLLA layers is weak preventing optimal enhancement of the mechanical properties and making the composites prone to breakdown. In the present study, poly (γ-benzyl-L-glutamate) modified hydroxyapatite/(poly (L-lactic acid)) (PBLG-g-HA/PLLA) composite scaffolds were fabricated with improved phase compatibility and tested for their osteogenic properties in 18 Wistar female rats by analyzing new bone formation in 3 mm bilateral femur defects in vivo. At time points, 2, 4 and 8 weeks post surgery, bone formation was evaluated by µ-CT and histological analysis by comparing 4 treatment groups; 1) blank defect, 2) PLLA, 3) HA/PLLA and 4) PBLG-g-HA/PLLA scaffolds. The in vivo analysis demonstrated that new bone formation was much more prominent in HA/PLLA and PBLG-g-HA/PLLA groups as depicted by µ-CT, H&E staining and immunohistochemistry for collagen I. TRAP staining was also utilized to determine the influence of osteoclast cell number and staining intensity to the various scaffolds. No significant differences in either staining intensity or osteoclast numbers between all treatment modalities was observed, however blank defects did contain a higher number of osteoclast-like cells. The results from the present study illustrate the potential of PBLG-g-HA/PLLA scaffolds for bone tissue engineering applications by demonstrating favorable osteogenic properties.

[Mathematical simulation of stem/cement/bone mechanical interactions for Poldi-Cech, CF-30, MS-30 and PFC femoral components].

PubMed

Kovanda, M; Havlícek, V; Hudec, J

2009-04-01

PURPOSE OF THE STUDY The mid-term longevity of femoral components varies considerably, with some showing failure due to early aseptic loosening. Since the hip joint is subject to heavy mechanical loads, it can be assumed that the mechanical interaction of the implant, bone cement and femur will play a key role in the resultant reliability of an arthroplasty. This study was designed to examine this mechanical interaction in four femoral components different in construction (Poldi-Cech, CF-30, MS-30 and PFC) using mathematical simulation. MATERIAL AND METHODS Four stem/cement/femur 3-D mathematical models, comparable in quality, infolving the Poldi-Cech, CF-30, MS-30 and PFC stems, respectively, were constructed. A 3-D model for each stem was created according to its real, middle-size femoral component. Each 3-D model of the cement mantle corresponded in shape to the mantle of the appropriate real stem, with its thickness based on the recommended values of 4-7 mm in the proximal and 1-3 mm in the distal part, and with the cement mantle reaching as far as 10 mm distal to the femoral stem tip. For simplicitys sake the outer surface of the cement mantle was simulated as smooth. A 3-D model involving the proximal epiphysis and the metaphysis of a femur was reconstructed, based on a series of CT cross-sections obtained periodically at 10.5-mm and 2.5-mm distances. The sten/cement/femur model with the MS-30 stem also included a centraliser. The mechanical interaction of the stem, bone cement and bone tissue was examined by means of mathematical stimulation using ANSYS 5.7 software based on finite element analysis. RESULTS For the sake of simplicity, only two key parameters are presented, namely, contact stress at the stem-cement interface and equivalent deformation in the stem/cement/femur system. The least satisfactory stress loading was in the CF-30 stem whose sharp edges showed the values of contact stress about six-times higher than on the mid-medial portion of the

Repair of rabbit cartilage defect based on the fusion of rabbit bone marrow stromal cells and Nano-HA/PLLA composite material.

PubMed

Zhu, Weimin; Guo, Daiqi; Peng, Liangquan; Chen, Yun Fang; Cui, Jiaming; Xiong, Jianyi; Lu, Wei; Duan, Li; Chen, Kang; Zeng, Yanjun; Wang, Daping

2017-02-01

Objective To assess the effect of the fusion of rabbit bone marrow stromal cells (rBMSCs) and Nano-hydroxyapatite/poly (l-lactic acid) (Nano-HA/PLLA) in repairing the rabbit knee joint with full-thickness cartilage defect. Method The rBMSCs were isolated and cultured in vitro, and the third generation of rBMSCs was co-cultured with the Nano-HA/PLLA to construct the tissue-engineered cartilage (TEC). Eighteen New Zealand white rabbits were selected and randomly divided into three groups, namely, TEC group, Nano-HA/PLLA group, and control group. A cartilage defect model with the diameter of 4.5 mm and depth of 5 mm was constructed on the articular surface of medial malleolus of rabbit femur. General observation, histological observation, and Wakitani's histological scoring were conducted in the 12th and 24th week postoperatively. Results The results of TEC group indicated that new cartilage tissue was formed on the defect site and subchondral bone achieved physiological integration basically. Histological and immunohistochemical analyses indicated the generation of massive extracellular matrix. In contrast, limited regeneration and reconstruction of cartilage was achieved in the Nano-HA/PLLA group and control group, with a significant difference from the TEC group (p < 0.05). Moreover, the effect of cartilage repair was positively correlated with time. Conclusion The porous Nano-HA/PLLA combined with BMSCs promoted the repair of weight-bearing bone of adult rabbit's knee joint with cartilage defect.

Just a drop of cement: a case of cervical spine bone aneurysmal cyst successfully treated by percutaneous injection of a small amount of polymethyl-methacrylate cement.

PubMed

Fahed, Robert; Clarençon, Frédéric; Riouallon, Guillaume; Cormier, Evelyne; Bonaccorsi, Raphael; Pascal-Mousselard, Hugues; Chiras, Jacques

2016-01-01

Aneurysmal bone cyst (ABC) is a benign hemorrhagic tumor, commonly revealed by local pain. The best treatment for this lesion is still controversial. We report the case of a patient with chronic neck pain revealing an ABC of the third cervical vertebra. After percutaneous injection of a small amount of polymethyl-methacrylate bone cement, the patient experienced significant clinical and radiological improvement. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Axial load-bearing capacity of an osteochondral autograft stabilized with a resorbable osteoconductive bone cement compared with a press-fit graft in a bovine model.

PubMed

Kiss, Marc-Olivier; Levasseur, Annie; Petit, Yvan; Lavigne, Patrick

2012-05-01

Osteochondral autografts in mosaicplasty are inserted in a press-fit fashion, and hence, patients are kept nonweightbearing for up to 2 months after surgery to allow bone healing and prevent complications. Very little has been published regarding alternative fixation techniques of those grafts. Osteochondral autografts stabilized with a resorbable osteoconductive bone cement would have a greater load-bearing capacity than standard press-fit grafts. Controlled laboratory study. Biomechanical testing was conducted on 8 pairs of cadaveric bovine distal femurs. For the first 4 pairs, 6 single osteochondral autografts were inserted in a press-fit fashion on one femur. On the contralateral femur, 6 grafts were stabilized with a calcium triglyceride osteoconductive bone cement. For the 4 remaining pairs of femurs, 4 groups of 3 adjacent press-fit grafts were inserted on one femur, whereas on the contralateral femur, grafts were cemented. After a maturation period of 48 hours, axial loading was applied on all single grafts and on the middle graft of each 3-in-a-row series. For the single-graft configuration, median loads required to sink the press-fit and cemented grafts by 2 and 3 mm were 281.87 N versus 345.56 N (P = .015) and 336.29 N versus 454.08 N (P = .018), respectively. For the 3-in-a-row configuration, median loads required to sink the press-fit and cemented grafts by 2 and 3 mm were 260.31 N versus 353.47 N (P = .035) and 384.83 N versus 455.68 N (P = .029), respectively. Fixation of osteochondral grafts using bone cement appears to improve immediate stability over the original mosaicplasty technique for both single- and multiple-graft configurations. Achieving greater primary stability of osteochondral grafts could potentially accelerate postoperative recovery, allowing early weightbearing and physical therapy.

Synergistic interaction of platelet derived growth factor (PDGF) with the surface of PLLA/Col/HA and PLLA/HA scaffolds produces rapid osteogenic differentiation.

PubMed

Raghavendran, Hanumantha Rao Balaji; Mohan, Saktiswaren; Genasan, Krishnamurithy; Murali, Malliga Raman; Naveen, Sangeetha Vasudevaraj; Talebian, Sepehr; McKean, Robert; Kamarul, Tunku

2016-03-01

Scaffolds with structural features similar to the extracellular matrix stimulate rapid osteogenic differentiation in favorable microenvironment and with growth factor supplementation. In this study, the osteogenic potential of electrospun poly-l-lactide/hydroxyapatite/collagen (PLLA/Col/HA, PLLA/HA and PLLA/Col) scaffolds were tested in vitro with the supplementation of platelet derived growth factor-BB (PDGF-BB). Cell attachment and topography, mineralization, extracellular matrix protein localization, and gene expression of the human mesenchymal stromal cells were compared between the fibrous scaffolds PLLA/Col/HA, PLLA/Col, and PLLA/HA. The levels of osteocalcin, calcium, and mineralization were significantly greater in the PLLA/Col/HA and PLLA/HA compared with PLLA/Col. High expression of fibronectin, intracellular adhesion molecule, cadherin, and collagen 1 (Col1) suggests that PLLA/Col/HA and PLLA/HA scaffolds had superior osteoinductivity than PLLA/Col. Additionally, osteopontin, osteocalcin, osterix, Runt-related transcription factor 2 (Runx2), and bone morphogenic protein (BMP2) expression were higher in PLLA/Col/HA and PLLA/HA compared with PLLA/Col. In comparison with PLLA/Col, the PLLA/Col/HA and PLLA/HA scaffolds presented a significant upregulation of the genes Runx2, Col 1, Integrin, osteonectin (ON), bone gamma-carboxyglutamic acid-containing protein (BGALP), osteopontin (OPN), and BMP2. The upregulation of these genes was further increased with PDGF-BB supplementation. These results show that PDGF-BB acts synergistically with PLLA/Col/HA and PLLA/HA to enhance the osteogenic differentiation potential. Therefore, this combination can be used for the rapid expansion of bone marrow stromal cells into bone-forming cells for tissue engineering. Copyright © 2015 Elsevier B.V. All rights reserved.

Graphene oxide versus graphene for optimisation of PMMA bone cement for orthopaedic applications.

PubMed

Paz, E; Forriol, F; Del Real, J C; Dunne, N

2017-08-01

Graphene (G) and graphene oxide (GO) nano-sized powders with loadings ranging from 0.1 to 1.0wt% were investigated as reinforced agents for polymethyl methacrylate (PMMA) bone cements. The mechanical properties (i.e. bend strength, bend modulus, compression strength, fracture toughness and fatigue performance) and the thermal properties (i.e. maximum temperature, setting time, curing heat and residual monomer) of the resultant nanocomposites were characterised. The mechanical performance of G-PMMA and GO-PMMA bone cements has been improved at low loadings (≤0.25wt%), especially the fracture toughness and fatigue performance. These improvements were attributed to the fact that the G and GO induced deviations in the crack fronts and hampered crack propagation. The high functionalisation of GO compared with G resulted in greater enhancements because it facilitated the creation of a stronger interfacial adhesion between the GO and PMMA. The use of loadings ≥0.25wt% showed a detriment in the mechanical performance as consequence of the formation of agglomerates as well as to an increase in the porosity. The increase in the residual monomer and the decrease in the curing heat, observed with the increase in the level of G and GO added, suggests that such materials retard and inhibit the curing reaction at high levels of loading by interfering in the radical reaction. Copyright © 2017 Elsevier B.V. All rights reserved.

Perfusion pressure of a new cannulating fenestrated pedicle screw during cement augmentation.

PubMed

Wang, Zhirong; Zhang, Wen; Xu, Hao; Lu, Aiqing; Yang, Huilin; Luo, Zong-Ping

2018-06-18

Cannulating fenestrated pedicle screws are effective for fixating osteoporotic vertebrae. However, a major limitation is the excessive pressure required to inject a sufficient amount of cement into the vertebral body through the narrow hole of a pedicle screw. We have recently proposed a new cannulating fenestrated pedicle screw with a large hole diameter and a matched inner pin for screw-strength maintenance. Our purpose was to determine whether the new screw can significantly reduce bone-cement perfusion pressure during cement augmentation, METHODS: Two different methods were used to examine perfusion pressure. Hagen-Poisseuille's flow model in a tube was used to calculate pressure drop in the bone-cement channel. Experimentally, both Newtonian silicone oil and bone-cement (polymethyl methacrylate) were tested using a cement pusher through the cannulating screw at a constant rate of 2 ml/min. The internal hollow portion of the screw was the bottleneck of the perfusion, and the new design significantly reduced the perfusion pressure. Specifically, perfusion pressure dropped by 59% (P < 0.05) when diameter size was doubled. The new design effectively improved the application of bone-cement augmentation with the ease of bone-cement perfusion, thereby enhancing operational safety. Copyright © 2018. Published by Elsevier Ltd.

Bone regeneration in experimental animals using calcium phosphate cement combined with platelet growth factors and human growth hormone.

PubMed

Emilov-Velev, K; Clemente-de-Arriba, C; Alobera-García, M Á; Moreno-Sansalvador, E M; Campo-Loarte, J

2015-01-01

Many substances (growth factors and hormones) have osteoinduction properties and when added to some osteoconduction biomaterial they accelerate bone neoformation properties. The materials included 15 New Zealand rabbits, calcium phosphate cement (Calcibon(®)), human growth hormone (GH), and plasma rich in platelets (PRP). Each animal was operated on in both proximal tibias and a critical size bone defect of 6mm of diameter was made. The animals were separated into the following study groups: Control (regeneration only by Calcibon®), PRP (regeneration by Calcibon® and PRP), GH (regeneration by Calcibon® and GH). All the animals were sacrificed at 28 days. An evaluation was made of the appearance of the proximal extreme of rabbit tibiae in all the animals, and to check the filling of the critical size defect. A histological assessment was made of the tissue response, the presence of new bone formation, and the appearance of the biomaterial. Morphometry was performed using the MIP 45 image analyser. ANOVA statistical analysis was performed using the Statgraphics software application. The macroscopic appearance of the critical defect was better in the PRP and the GH group than in the control group. Histologically greater new bone formation was found in the PRP and GH groups. No statistically significant differences were detected in the morphometric study between bone formation observed in the PRP group and the control group. Significant differences in increased bone formation were found in the GH group (p=0.03) compared to the other two groups. GH facilitates bone regeneration in critical defects filled with calcium phosphate cement in the time period studied in New Zealand rabbits. Copyright © 2014 SECOT. Published by Elsevier Espana. All rights reserved.

A small punch test technique for characterizing the elastic modulus and fracture behavior of PMMA bone cement used in total joint replacement.

PubMed

Giddings, V L; Kurtz, S M; Jewett, C W; Foulds, J R; Edidin, A A

2001-07-01

Polymethylmethacrylate (PMMA) bone cement is used in total joint replacements to anchor implants to the underlying bone. Establishing and maintaining the integrity of bone cement is thus of critical importance to the long-term outcome of joint replacement surgery. The goal of the present study was to evaluate the suitability of a novel testing technique, the small punch or miniaturized disk bend test, to characterize the elastic modulus and fracture behavior of PMMA. We investigated the hypothesis that the crack initiation behavior of PMMA during the small punch test was sensitive to the test temperature. Miniature disk-shaped specimens, 0.5 mm thick and 6.4 mm in diameter, were prepared from PMMA and Simplex-P bone cement according to manufacturers' instructions. Testing was conducted at ambient and body temperatures, and the effect of test temperature on the elastic modulus and fracture behavior was statistically evaluated using analysis of variance. For both PMMA materials, the test temperature had a significant effect on elastic modulus and crack initiation behavior. At body temperature, the specimens exhibited "ductile" crack initiation, whereas at room temperature "brittle" crack initiation was observed. The small punch test was found to be a sensitive and repeatable test method for evaluating the mechanical behavior of PMMA. In light of the results of this study, future small punch testing should be conducted at body temperature.

Composite bone cements loaded with a bioactive and ferrimagnetic glass-ceramic: Leaching, bioactivity and cytocompatibility.

PubMed

Verné, Enrica; Bruno, Matteo; Miola, Marta; Maina, Giovanni; Bianco, Carlotta; Cochis, Andrea; Rimondini, Lia

2015-08-01

In this work, composite bone cements, based on a commercial polymethylmethacrylate matrix (Palamed®) loaded with ferrimagnetic bioactive glass-ceramic particles (SC45), were produced and characterized in vitro. The ferrimagnetic bioactive glass-ceramic belongs to the system SiO2-Na2O-CaO-P2O5-FeO-Fe2O3 and contains magnetite (Fe3O4) crystals into a residual amorphous bioactive phase. Three different formulations (containing 10, 15 and 20 wt.% of glass-ceramic particles respectively) have been investigated. These materials are intended to be applied as bone fillers for the hyperthermic treatment of bone tumors. The morphological, compositional, calorimetric and mechanical properties of each formulation have been already discussed in a previous paper. The in vitro properties of the composite bone cements described in the present paper are related to iron ion leaching test (by graphite furnace atomic absorption spectrometer), bioactivity (i.e. the ability to stimulate the formation of a hydroxyapatite - HAp - layer on their surface after soaking in simulated body fluid SBF) and cytocompatibility toward human osteosarcoma cells (ATCC CRL-1427, Mg63). Morphological and chemical characterizations by scanning electron microscopy and energy dispersion spectrometry have been performed on the composite samples after each test. The iron release was negligible and all the tested samples showed the growth of HAp on their surface after 28 days of immersion in a simulated body fluid (SBF). Cells showed good viability, morphology, adhesion, density and the ability to develop bridge-like structures on all investigated samples. A synergistic effect between bioactivity and cell mineralization was also evidenced. Copyright © 2015 Elsevier B.V. All rights reserved.

In Vitro and In Vivo Evaluations of Nano-Hydroxyapatite/Polyamide 66/Glass Fibre (n-HA/PA66/GF) as a Novel Bioactive Bone Screw

PubMed Central

Su, Bao; Peng, Xiaohua; Jiang, Dianming; Wu, Jun; Qiao, Bo; Li, Weichao; Qi, Xiaotong

2013-01-01

In this study, we prepared nano-hydroxyapatite/polyamide 66/glass fibre (n-HA/PA66/GF) bioactive bone screws. The microstructure, morphology and coating of the screws were characterised, and the adhesion, proliferation and viability of MC3T3-E1 cells on n-HA/PA66/GF scaffolds were determined using scanning electron microscope, CCK-8 assays and cellular immunofluorescence analysis. The results confirmed that n-HA/PA66/GF scaffolds were biocompatible and had no negative effect on MC3T3-E1 cells in vitro. To investigate the in vivo biocompatibility, internal fixation properties and osteogenesis of the bioactive screws, both n-HA/PA66/GF screws and metallic screws were used to repair intercondylar femur fractures in dogs. General photography, CT examination, micro-CT examination, histological staining and biomechanical assays were performed at 4, 8, 12 and 24 weeks after operation. The n-HA/PA66/GF screws exhibited good biocompatibility, high mechanical strength and extensive osteogenesis in the host bone. Moreover, 24 weeks after implantation, the maximum push-out load of the bioactive screws was greater than that of the metallic screws. As shown by their good cytocompatibility, excellent biomechanical strength and fast formation and ingrowth of new bone, n-HA/PA66/GF screws are thus suitable for orthopaedic clinical applications. PMID:23861888

In vitro assessment of nanosilver-functionalized PMMA bone cement on primary human mesenchymal stem cells and osteoblasts.

PubMed

Pauksch, Linda; Hartmann, Sonja; Szalay, Gabor; Alt, Volker; Lips, Katrin S

2014-01-01

Peri-prosthetic infections caused by multidrug resistant bacteria have become a serious problem in surgery and orthopedics. The aim is to introduce biomaterials that avoid implant-related infections caused by multiresistant bacteria. The efficacy of silver nanoparticles (AgNP) against a broad spectrum of bacteria and against multiresistant pathogens has been repeatedly described. In the present study polymethylmethacrylate (PMMA) bone cement functionalized with AgNP and/or gentamicin were tested regarding their biocompatibility with bone forming cells. Therefore, influences on viability, cell number and differentiation of primary human mesenchymal stem cells (MSCs) and MSCs cultured in osteogenic differentiation media (MSC-OM) caused by the implant materials were studied. Furthermore, the growth behavior and the morphology of the cells on the testing material were observed. Finally, we examined the induction of cell stress, regarding antioxidative defense and endoplasmatic reticulum stress. We demonstrated similar cytocompatibility of PMMA loaded with AgNP compared to plain PMMA or PMMA loaded with gentamicin. There was no decrease in cell number, viability and osteogenic differentiation and no induction of cell stress for all three PMMA variants after 21 days. Addition of gentamicin to AgNP-loaded PMMA led to a slight decrease in osteogenic differentiation. Also an increase in cell stress was detectable for PMMA loaded with gentamicin and AgNP. In conclusion, supplementation of PMMA bone cement with gentamicin, AgNP, and both results in bone implants with an antibacterial potency and suitable cytocompatibility in MSCs and MSC-OM.

Effect of storage temperature and equilibration time on polymethyl methacrylate (PMMA) bone cement polymerization in joint replacement surgery.

PubMed

Koh, Bryan T H; Tan, J H; Ramruttun, Amit Kumarsing; Wang, Wilson

2015-11-17

In cemented joint arthroplasty, the handling characteristics (doughing, working, and setting times) of polymethyl methacrylate (PMMA) bone cement is important as it determines the amount of time surgeons have to optimally position an implant. Storage conditions (temperature and humidity) and the time given for PMMA cement to equilibrate to ambient operating theater (OT) temperatures are often unregulated and may lead to inconsistencies in its handling characteristics. This has not been previously studied. Hence, the purpose of this study was to investigate the effect of storage temperatures on the handling characteristics of PMMA cement and the duration of equilibration time needed at each storage temperature to produce consistent and reproducible doughing, setting, and working times. SmartSet® HV cement was stored at three different controlled temperatures: 20 °C (control), 24 °C, and 28 °C for at least 24 h prior to mixing. The cement components were then brought into a room kept at 20 °C and 50 % humidity. Samples were allowed to equilibrate to ambient conditions for 15, 30, 45, and 60 min. The cement components were mixed and the dough time, temperature-versus-time curve (Lutron TM-947SD, Lutron Electronics, Inc., Coopersburg, PA), and setting time were recorded. Analysis was performed using the two-way ANOVA test (IBM SPSS Statistics V.22). At 20 °C (control) storage temperature, the mean setting time was 534 ± 17 s. At 24 °C storage temperature, the mean setting time was 414 ± 6 s (p < 0.001*) with 15 min of equilibration, 446 ± 11 s (p < 0.001*) with 30 min of equilibration, 501 ± 12 s (p < 0.001*) with 45 min of equilibration, and 528 ± 15 (p > 0.05) with 60 min of equilibration. At 28 °C storage temperature, the mean setting time was 381 ± 8 s (p < 0.001*) with 15 min of equilibration, 432 ± 30 s (p < 0.001*) with 30 min of equilibration, 487 ± 9 (p < 0

Does a simple syringe applicator enhance bone cement set up time in knee arthroplasty?

PubMed Central

Sodhi, Nipun; Dalton, Sarah E.; Khlopas, Anton; Sultan, Assem A.; Curtis, Gannon L.; Harb, Matthew A.; Naziri, Qais; Barrington, John W.; Mont, Michael A.

2017-01-01

Background The time required for polymethylmethacrylate (PMMA) cement curing or hardening can be modified by a number of variables including the mixing technique, and the temperature and pressure at which the process is taking place. Therefore, the purpose of this study was to evaluate two different methods of PMMA application in terms of set up time. Specifically, we (I) compared the PMMA set up time of cement that remained in the mixing bowl to cement that was placed in a syringe and (II) extrapolated the associated annual cost difference on the national and individual surgeon levels. Methods The cement set up time was measured for a total of 146 consecutive patients who underwent either unicompartmental knee arthroplasty (n=136) or patellofemoral arthroplasty (n=10) between January 2016 and April 2017. One pack of PMMA powder and monomer were mixed, placed in a 300 mL small plastic bowl, and mixed with a tongue depressor. Then, 50 mL of the mixed PMMA was placed in a sterile 60 mL syringe with the tip cut to a 6-mm opening, and the syringe was used to apply the cement to the bone and the prosthesis surface. The remaining unused cement in the syringe (syringe group) and the remaining unused cement in the plastic bowl (bowl group) were removed and formed into a two separate 2 cm diameter cubes that were allowed to cure at room temperature on a sterile set of osteotomes. The two cubes of cement were timed for complete PMMA curing. A two-tailed student’s t-test was used to compare the curing time for the two groups. Annual cost differences were calculated on the national and individual surgeon level. The total number of daily cases performed and the operative time savings using the syringe applicator was used to find daily and annual cost savings. Results The mean time for the cement to set up in the bowl group was 16.8±2.1 minutes, and the mean time for cement set up in the syringe group was 15.1±1.7 minutes. Compared to the bowl group cement set up time, the

Percutaneous osteoplasty with a bone marrow nail for fractures of long bones: experimental study.

PubMed

Nakata, Kouhei; Kawai, Nobuyuki; Sato, Morio; Cao, Guang; Sahara, Shinya; Tanihata, Hirohiko; Takasaka, Isao; Minamiguchi, Hiroyuki; Nakai, Tomoki

2010-09-01

To develop percutaneous osteoplasty with the use of a bone marrow nail for fixation of long-bone fractures, and to evaluate its feasibility and safety in vivo and in vitro. Six long bones in three healthy swine were used in the in vivo study. Acrylic cement was injected through an 11-gauge bone biopsy needle and a catheter into a covered metallic stent placed within the long bone, creating a bone marrow nail. In the in vitro study, we determined the bending, tug, and compression strengths of the acrylic cement nails 9 cm long and 8 mm in diameter (N = 10). The bending strength of the artificially fractured bones (N = 6) restored with the bone marrow nail and cement augmentation was then compared with that of normal long bones (N = 6). Percutaneous osteoplasty with a bone marrow nail was successfully achieved within 1 hour for all swine. After osteoplasty, all swine regained the ability to run until they were euthanized. Blood tests and pathologic findings showed no adverse effects. The mean bending, tug, and compression strengths of the nail were 91.4 N/mm(2) (range, 75.0-114.1 N/mm(2)), 20.9 N/mm(2) (range, 6.6-30.4 N/mm(2)), and 103.0 N/mm(2) (range, 96.3-110.0 N/mm(2)), respectively. The bending strength ratio of artificially fractured bones restored with bone marrow nail and cement augmentation to normal long bone was 0.32. Percutaneous osteoplasty with use of a bone marrow nail and cement augmentation appears to have potential in treating fractures of non-weight-bearing long bones. Copyright 2010 SIR. Published by Elsevier Inc. All rights reserved.

Brittle and ductile adjustable cement derived from calcium phosphate cement/polyacrylic acid composites.

PubMed

Chen, Wen-Cheng; Ju, Chien-Ping; Wang, Jen-Chyan; Hung, Chun-Cheng; Chern Lin, Jiin-Huey

2008-12-01

Bone filler has been used over the years in dental and biomedical applications. The present work is to characterize a non-dispersive, fast setting, modulus adjustable, high bioresorbable composite bone cement derived from calcium phosphate-based cement combined with polymer and binding agents. This cement, we hope, will not swell in simulated body fluid and keep the osteogenetic properties of the dry bone and avoid its disadvantages of being brittle. We developed a calcium phosphate cement (CPC) of tetracalcium phosphate/dicalcium phosphate anhydrous (TTCP/DCPA)-polyacrylic acid with tartaric acid, calcium fluoride additives and phosphate hardening solution. The results show that while composite, the hard-brittle properties of 25wt% polyacrylic acid are proportional to CPC and mixing with additives is the same as those of the CPC without polyacrylic acid added. With an increase of polyacrylic acid/CPC ratio, the 67wt% samples revealed ductile-tough properties and 100wt% samples kept ductile or elastic properties after 24h of immersion. The modulus range of this development was from 200 to 2600MPa after getting immersed in simulated body fluid for 24h. The TTCP/DCPA-polyacrylic acid based CPC demonstrates adjustable brittle/ductile strength during setting and after immersion, and the final reaction products consist of high bioresorbable monetite/brushite/calcium fluoride composite with polyacrylic acid.

Novel self-gelling injectable hydrogel/alpha-tricalcium phosphate composites for bone regeneration: Physiochemical and microcomputer tomographical characterization.

PubMed

Douglas, Timothy E L; Schietse, Josefien; Zima, Aneta; Gorodzha, Svetlana; Parakhonskiy, Bogdan V; KhaleNkow, Dmitry; Shkarin, Roman; Ivanova, Anna; Baumbach, Tilo; Weinhardt, Venera; Stevens, Christian V; Vanhoorne, Valérie; Vervaet, Chris; Balcaen, Lieve; Vanhaecke, Frank; Slośarczyk, Anna; Surmeneva, Maria A; Surmenev, Roman A; Skirtach, Andre G

2018-03-01

Mineralized hydrogels are increasingly gaining attention as biomaterials for bone regeneration. The most common mineralization strategy has been addition of preformed inorganic particles during hydrogel formation. This maintains injectability. One common form of bone cement is formed by mixing particles of the highly reactive calcium phosphate alpha-tricalcium phosphate (α-TCP) with water to form hydroxyapatite (HA). The calcium ions released during this reaction can be exploited to crosslink anionic, calcium-binding polymers such as the polysaccharide gellan gum (GG) to induce hydrogel formation. In this study, three different amounts of α-TCP particles were added to GG polymer solution to generate novel, injectable hydrogel-inorganic composites. Distribution of the inorganic phase in the hydrogel was studied by high resolution microcomputer tomography (µCT). Gelation occurred within 30 min. α-TCP converted to HA. µCT revealed inhomogeneous distribution of the inorganic phase in the composites. These results demonstrate the potential of the composites as alternatives to traditional α-TCP bone cement and pave the way for incorporation of biologically active substances and in vitro and in vivo testing. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 822-828, 2018. © 2017 Wiley Periodicals, Inc.

Spatial resolution and measurement uncertainty of strains in bone and bone-cement interface using digital volume correlation.

PubMed

Zhu, Ming-Liang; Zhang, Qing-Hang; Lupton, Colin; Tong, Jie

2016-04-01

The measurement uncertainty of strains has been assessed in a bone analogue (sawbone), bovine trabecular bone and bone-cement interface specimens under zero load using the Digital Volume Correlation (DVC) method. The effects of sub-volume size, sample constraint and preload on the measured strain uncertainty have been examined. There is generally a trade-off between the measurement uncertainty and the spatial resolution. Suitable sub-volume sizes have been be selected based on a compromise between the measurement uncertainty and the spatial resolution of the cases considered. A ratio of sub-volume size to a microstructure characteristic (Tb.Sp) was introduced to reflect a suitable spatial resolution, and the measurement uncertainty associated was assessed. Specifically, ratios between 1.6 and 4 appear to give rise to standard deviations in the measured strains between 166 and 620 με in all the cases considered, which would seem to suffice for strain analysis in pre as well as post yield loading regimes. A microscale finite element (μFE) model was built from the CT images of the sawbone, and the results from the μFE model and a continuum FE model were compared with those from the DVC. The strain results were found to differ significantly between the two methods at tissue level, consistent in trend with the results found in human bones, indicating mainly a limitation of the current DVC method in mapping strains at this level. Copyright © 2015 Elsevier Ltd. All rights reserved.

Fabrication and characterization of nanoengineered biocompatible n-HA/chitosan-tamarind seed polysaccharide: Bio-inspired nanocomposites for bone tissue engineering.

PubMed

Shakir, Mohammad; Zia, Iram; Rehman, Abdur; Ullah, Rizwan

2018-05-01

In this communication we describe the fabrication of nano-hydroxyapatite/chitosan-tamarind seed polysaccharide (n-HA/CS-TSP) nanocomposite with a weight ratio of 70/20/10, 70/15/15 and 70/10/20, respectively through a co-precipitation method. A comparative assessment of the properties of n-HA/CS-TSP and n-HA/CS nanocomposites was done by FT-IR, SEM-EDX, TEM, TGA/DTA, XRD and mechanical testing. The results suggested strong chemical interactions between the three components, decreased particle size and homogeneous dispersion of n-HA particles in n-HA/CS-TSP as compared to n-HA/CS. The n-HA/CS-TSP (70/10/20) showed the most porous and rough surface, enhanced thermal stability and highest compressive strength (4.0 MPa) and modulus (81 MPa). In addition, n-HA/CS-TSP (70/10/20) exhibited greater swelling character, acceptable degradation and increased biomineralization in simulated body fluid (SBF) as compared to n-HA/CS-TSP (70/20/10, 70/15/15) and n-HA/CS nanocomposites. The superior non-toxic response with MG-63 cells and better haemocompatibility was observed with n-HA/CS-TSP (70/15/15). Thereby, n-HA/CS-TSP nanocomposites could be promising alternative biomaterials in the field of bone tissue engineering compared to the n-HA/CS nanocomposite. Copyright © 2018 Elsevier B.V. All rights reserved.

Modified femoral pressuriser generates a longer lasting high pressure during cement pressurisation

PubMed Central

2011-01-01

Background The strength of the cement-bone interface in hip arthroplasty is strongly related to cement penetration into the bone. A modified femoral pressuriser has been investigated, designed for closer fitting into the femoral opening to generate higher and more constant cement pressure compared to a commercial (conventional) design. Methods Femoral cementation was performed in 10 Sawbones® models, five using the modified pressuriser and five using a current commercial pressuriser as a control. Pressure during the cementation was recorded at the proximal and distal regions of the femoral implant. The peak pressure and the pressure-time curves were analysed by student's t-test and Two way ANOVA. Results The modified pressuriser showed significantly and substantially longer durations at higher cementation pressures and slightly, although not statistically, higher peak pressures compared to the conventional pressuriser. The modified pressuriser also produced more controlled cement leakage. Conclusion The modified pressuriser generates longer higher pressure durations in the femoral model. This design modification may enhance cement penetration into cancellous bone and could improve femoral cementation. PMID:22004662

Evaluation of damage progression and mechanical behavior under compression of bone cements containing core-shell nanoparticles by using acoustic emission technique.

PubMed

Pacheco-Salazar, O F; Wakayama, Shuichi; Sakai, Takenobu; Cauich-Rodríguez, J V; Ríos-Soberanis, C R; Cervantes-Uc, J M

2015-06-01

In this work, the effect of the incorporation of core-shell particles on the fracture mechanisms of the acrylic bone cements by using acoustic emission (AE) technique during the quasi-static compression mechanical test was investigated. Core-shell particles were composed of a poly(butyl acrylate) (PBA) rubbery core and a methyl methacrylate/styrene copolymer (P(MMA-co-St)) outer glassy shell. Nanoparticles were prepared with different core-shell ratio (20/80, 30/70, 40/60 and 50/50) and were incorporated into the solid phase of bone cement at several percentages (5, 10 and 15 wt%). It was observed that the particles exhibited a spherical morphology averaging ca. 125 nm in diameter, and the dynamic mechanical analysis (DMA) thermograms revealed the desired structuring pattern of phases associated with core-shell structures. A fracture mechanism was proposed taking into account the detected AE signals and the scanning electron microscopy (SEM) micrographs. In this regard, core-shell nanoparticles can act as both additional nucleation sites for microcracks (and crazes) and to hinder the microcrack propagation acting as a barrier to its growth; this behavior was presented by all formulations. Cement samples containing 15 wt% of core-shell nanoparticles, either 40/60 or 50/50, were fractured at 40% deformation. This fact seems related to the coalescence of microcracks after they surround the agglomerates of core-shell nanoparticles to continue growing up. This work also demonstrated the potential of the AE technique to be used as an accurate and reliable detection tool for quasi-static compression test in acrylic bone cements. Copyright © 2015 Elsevier Ltd. All rights reserved.

Development of a Biodegradable Bone Cement for Craniofacial Applications

PubMed Central

Henslee, Allan M.; Gwak, Dong-Ho; Mikos, Antonios G.; Kasper, F. Kurtis

2015-01-01

This study investigated the formulation of a two-component biodegradable bone cement comprising the unsaturated linear polyester macromer poly(propylene fumarate) (PPF) and crosslinked PPF microparticles for use in craniofacial bone repair applications. A full factorial design was employed to evaluate the effects of formulation parameters such as particle weight percentage, particle size, and accelerator concentration on the setting and mechanical properties of crosslinked composites. It was found that the addition of crosslinked microparticles to PPF macromer significantly reduced the temperature rise upon crosslinking from 100.3 ± 21.6 to 102.7 ± 49.3 °C for formulations without microparticles to 28.0 ± 2.0 to 65.3 ± 17.5 °C for formulations with microparticles. The main effects of increasing the particle weight percentage from 25 to 50% were to significantly increase the compressive modulus by 37.7 ± 16.3 MPa, increase the compressive strength by 2.2 ± 0.5 MPa, decrease the maximum temperature by 9.5 ± 3.7 °C, and increase the setting time by 0.7 ± 0.3 min. Additionally, the main effects of increasing the particle size range from 0–150 μm to 150–300 μm were to significantly increase the compressive modulus by 31.2 ± 16.3 MPa and the compressive strength by 1.3 ± 0.5 MPa. However, the particle size range did not have a significant effect on the maximum temperature and setting time. Overall, the composites tested in this study were found to have properties suitable for further consideration in craniofacial bone repair applications. PMID:22499285

PLGA/nHA hybrid nanofiber scaffold as a nanocargo carrier of insulin for accelerating bone tissue regeneration

NASA Astrophysics Data System (ADS)

Haider, Adnan; Gupta, Kailash Chandra; Kang, Inn-Kyu

2014-06-01

The development of tissue engineering in the field of orthopedic surgery is booming. Two fields of research in particular have emerged: approaches for tailoring the surface properties of implantable materials with osteoinductive factors as well as evaluation of the response of osteogenic cells to these fabricated implanted materials (hybrid material). In the present study, we chemically grafted insulin onto the surface of hydroxyapatite nanorods (nHA). The insulin-grafted nHAs (nHA-I) were dispersed into poly(lactide-co-glycolide) (PLGA) polymer solution, which was electrospun to prepare PLGA/nHA-I composite nanofiber scaffolds. The morphology of the electrospun nanofiber scaffolds was assessed by field emission scanning electron microscopy (FESEM). After extensive characterization of the PLGA/nHA-I and PLGA/nHA composite nanofiber scaffolds by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction spectroscopy (XRD), X-ray photoelectron spectroscopy (XPS), energy-dispersive X-ray spectrometry (EDS), and transmission electron microscopy (TEM), the PLGA/nHA-I and PLGA/nHA (used as control) composite nanofiber scaffolds were subjected to cell studies. The results obtained from cell adhesion, alizarin red staining, and Von Kossa assay suggested that the PLGA/nHA-I composite nanofiber scaffold has enhanced osteoblastic cell growth, as more cells were proliferated and differentiated. The fact that insulin enhanced osteoblastic cell proliferation will open new possibilities for the development of artificial scaffolds for bone tissue regeneration.

Migration of polyethylene debris along well-fixed cemented implants.

PubMed

Massin, P; Viguier, E; Flautre, B; Hardouin, P; Astoin, E; Duponchel, B

2004-02-15

Implants, consisting of smooth Inox cylinders, were cemented into the lower femur and upper tibia of nine sheep to study the distal migration of polyethylene particles. Some implants had a titanium-bead porous coat at the proximal end. These were of three types: In the first type, the porous coat was covered with hydroxyapatite to obtain a bony seal; the second type was prepared for a polymethylmethacrylate seal; in the third type, the porous zone was surrounded by a 2-mm-thick space to allow the formation of a fibrous seal. Small polyethylene particles were injected into the knees once a week during the third and fourth months after implantation. The animals were euthanized 2 months later. Major longitudinal sections of the implants and the surrounding bone were examined under a polarized light microscope. Birefringent particles were counted at the cement-bone and cement-implant interfaces. Osteolysis was not observed. None of the seals significantly decreased the migration of particles around the cemented part of the implants. Particles were observed in cement fissures and vacuoles. They migrated at both interfaces and in the bone itself. They were visible in marrow spaces between bone trabeculae. Copyright 2003 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 68B: 140-148, 2004

The dynamic volume changes of polymerising polymethyl methacrylate bone cement.

PubMed

Muller, Scott D; Green, Sarah M; McCaskie, Andrew W

2002-12-01

The Swedish hip register found an increased risk of early revision of vacuum-mixed cemented total hip replacements. The influence of cement mixing technique on the dynamic volume change in polymerising PMMA is not well understood and may be relevant to this observation. Applying Archimedes' principle, we have investigated the dynamic volume changes in polymerising cement and determined the influence of mixing technique. All specimens showed an overall volume reduction: hand-mixed 3.4% and vacuum-mixed 6.0%. Regression analysis of sectional porosity and volume reduction showed a highly significant relationship. Hand-mixed porous cement showed a transient volume increase before solidification. However, vacuum-mixed cement showed a progressive volume reduction throughout polymerisation. Transient expansion of porous cement occurs at the critical time of micro-interlock formation, possibly improving fixation. Conversely, progressive volume reduction of vacuum-mixed cement throughout the formation of interlock may damage fixation. Stable fixation of vacuum-mixed cement may depend on additional techniques to offset the altered volumetric behaviour of vacuum-mixed cement.

Biocompatibility of calcium phosphate bone cement with optimized mechanical properties.

PubMed

Palmer, Iwan; Nelson, John; Schatton, Wolfgang; Dunne, Nicholas J; Buchanan, Fraser J; Clarke, Susan A

2016-02-01

The broad aim of this work was to investigate and optimize the properties of calcium phosphate bone cements (CPCs) for use in vertebroplasty to achieve effective primary fixation of spinal fractures. The incorporation of collagen, both bovine and from a marine sponge (Chondrosia reniformis), into a CPC was investigated. The biological properties of the CPC and collagen-CPC composites were assessed in vitro through the use of human bone marrow stromal cells. Cytotoxicity, proliferation, and osteoblastic differentiation were evaluated using lactate dehydrogenase, PicoGreen, and alkaline phosphatase activity assays, respectively. The addition of both types of collagen resulted in an increase in cytotoxicity, albeit not to a clinically relevant level. Cellular proliferation after 1, 7, and 14 days was unchanged. The osteogenic potential of the CPC was reduced through the addition of bovine collagen but remained unchanged in the case of the marine collagen. These findings, coupled with previous work showing that incorporation of marine collagen in this way can improve the physical properties of CPCs, suggest that such a composite may offer an alternative to CPCs in applications where low setting times and higher mechanical stability are important. © 2015 The Authors. Journal of Biomedical Materials Research Part B: Applied Biomaterials Published by Wiley Periodicals, Inc.

Biochemical changes on the repair of surgical bone defects grafted with biphasic synthetic micro-granular HA + β-tricalcium phosphate induced by laser and LED phototherapies assessed by Raman spectroscopy

NASA Astrophysics Data System (ADS)

Pinheiro, Antonio Luiz B.; Soares, Luiz Guilherme P.; Marques, Aparecida Maria C.; Silveira, Landulfo

2016-03-01

This work aimed the assessment of the biochemical changes during bone mineralization induced by laser and LED irradiation in an animal model of bone repair using a spectral model based on Raman spectroscopy. Six groups were studied: Clot, Laser (λ780 nm, 70 mW), LED (λ850 nm +/- 10 nm, 150 mW), Biomaterial (biphasic synthetic microgranular hydroxyapatite (HA) + β-tricalcium phosphate), Laser + Biomaterial and LED + Biomaterial. When indicated, defects were further irradiated at 48 h interval during 2 wks, 20 J/cm2 per session. At 15th and 30th days, femurs were dissected and spectra of the defects were collected. Raman spectra were submitted to a model to estimate the relative amount of collagen, phosphate HA and carbonate HA, by using spectra of pure collagen, biomaterial and basal bone, respectively. At 15th days, the use of biomaterial associated to phototherapy reduced the collagen formation, whereas the amount of carbonate HA was not different in all groups. The phosphate HA was higher in the groups that received biomaterial grafts. At 30th days, it was observed an increase of collagen for the group Laser + Biomaterial, and a reduction in the carbonate HA for the LED + Biomaterial. The phosphate HA was higher for the groups LED + Biomaterial and Laser + Biomaterial, while decreased for the group Biomaterial. These results indicated that the use of Laser and LED phototherapies improved the repair of bone defects grafted with the biomaterial by increasing the collagen deposition and phosphate HA.

Reinforcement of osteosynthesis screws with brushite cement.

PubMed

Van Landuyt, P; Peter, B; Beluze, L; Lemaître, J

1999-08-01

The fixation of osteosynthesis screws remains a severe problem for fracture repair among osteoporotic patients. Polymethyl-methacrylate (PMMA) is routinely used to improve screw fixation, but this material has well-known drawbacks such as monomer toxicity, exothermic polymerization, and nonresorbability. Calcium phosphate cements have been developed for several years. Among these new bone substitution materials, brushite cements have the advantage of being injectable and resorbable. The aim of this study is to assess the reinforcement of osteosynthesis screws with brushite cement. Polyurethane foams, whose density is close to that of cancellous bone, were used as bone model. A hole was tapped in a foam sample, then brushite cement was injected. Trabecular osteosynthesis screws were inserted. After 24 h of aging in water, the stripping force was measured by a pull-out test. Screws (4.0 and 6.5 mm diameter) and two foam densities (0.14 and 0.28 g/cm3) were compared. Cements with varying solid/liquid ratios and xanthan contents were used in order to obtain the best screw reinforcement. During the pull-out test, the stripping force first increases to a maximum, then drops to a steady-state value until complete screw extraction. Both maximum force and plateau value increase drastically in the presence of cement. The highest stripping force is observed for 6.5-mm screws reinforced with cement in low-density foams. In this case, the stripping force is multiplied by 3.3 in the presence of cement. In a second experiment, cements with solid/liquid ratio ranging from 2.0 to 3.5 g/mL were used with 6.5-mm diameter screws. In some compositions, xanthan was added to improve injectability. The best results were obtained with 2.5 g/mL cement containing xanthan and with 3.0 g/mL cements without xanthan. A 0.9-kN maximal stripping force was observed with nonreinforced screws, while 1.9 kN was reached with reinforced screws. These first results are very promising regarding screw

A comparison of distal canal restrictors in primary cemented femoral hip arthroplasty.

PubMed

Smith, Eric L; Wohlrab, Kurt P; Matzkin, Elizabeth G; Providence, Bertram C

2004-08-01

A retrospective study evaluated 75 total hip arthroplasties performed over a 4-year period using 4 different cement restrictors. A harvested bone restrictor, polyethylene restrictor (Smith & Nephew, Richards Inc, Memphis, Tenn), Biostop G (Depuy Orthopaedics, Warsaw, Ind), and polymethylmethacrylate (PMMA) (Wright Medical Technology, Arlington, Tex) were compared for the percentage of failures, the average length of the cement mantle, and the width of the femoral canal compared to the cement grade. Patient age, sex, and cement type were also evaluated for their influence on cement grade. The PMMA restrictor and bone performed better than the Richards plug and Biostop G restrictor.

Effect of Water-Glass Coating on HA and HA-TCP Samples for MSCs Adhesion, Proliferation, and Differentiation.

PubMed

Bajpai, Indu; Kim, Duk Yeon; Kyong-Jin, Jung; Song, In-Hwan; Kim, Sukyoung

2016-01-01

Ca-P and silicon based materials have become very popular as bone tissue engineering materials. In this study, water-glass (also known as sodium silicate glass) was coated on sintered hydroxyapatite (HA) and HA-TCP (TCP stands for tricalcium phosphate) samples and subsequently heat-treated at 600°C for 2 hrs. X-rays diffraction showed the presence of β- and α-TCP phases along with HA in the HA-TCP samples. Samples without coating, with water-glass coating, and heat-treated after water-glass coating were used to observe the adhesion and proliferation response of bone marrow derived-mesenchymal stem cells (MSCs). Cell culture was carried out for 4 hrs, 1 day, and 7 days. Interestingly, all samples showed similar response for cell adhesion and proliferation up to 7-day culture but fibronectin, E-cadherin, and osteogenic differentiation related genes (osteocalcin and osteopontin) were significantly induced in heat-treated water-glass coated HA-TCP samples. A water-glass coating on Ca-P samples was not found to influence the cell proliferation response significantly but activated some extracellular matrix genes and induced osteogenic differentiation in the MSCs.

Nanocomposite Porous Microcarriers Based on Strontium-Substituted HA- g-Poly(γ-benzyl-l-glutamate) for Bone Tissue Engineering.

PubMed

Yan, Shifeng; Xia, Pengfei; Xu, Shenghua; Zhang, Kunxi; Li, Guifei; Cui, Lei; Yin, Jingbo

2018-05-04

Porous microcarriers have aroused increasing attention recently, which can create a protected environment for sufficient cell seeding density, facilitate oxygen and nutrient transfer, and well support the cell attachment and growth. In this study, porous microcarriers fabricated from the strontium-substituted hydroxyapatite- graft-poly(γ-benzyl-l-glutamate) (Sr10-HA- g-PBLG) hybrid nanocomposite were developed. The surface grating of PBLG, the micromorphology and element distribution, mechanical strength, in vitro degradation, and Sr 2+ ion release of the obtained Sr10-HA- g-PBLG porous microcarriers were investigated, respectively. The grafting ratio and the molecular weight of the grafted PBLG of Sr10-HA- g-PBLG could be effectively controlled by varying the initial ratio of BLG-NCA to Sr10-HA-NH 2 . The microcarriers exhibited a highly porous and interconnected microstructure with the porosity of about 90% and overall density of 1.03-1.06 g/cm 3 . Also, the degradation rate of Sr10-HA-PBLG microcarriers could be effectively controlled and long-term Sr 2+ release was obtained. The Sr10-HA-PBLG microcarriers allowed cells adhesion, infiltration, and proliferation and promoted the osteogenic differentiation of rabbit adipose-derived stem cells (ADSCs). Successful healing of femoral bone defect was proved by injection of the ADSCs-seeded Sr10-HA-PBLG microcarriers in a rabbit model.

Characterization of New PEEK/HA Composites with 3D HA Network Fabricated by Extrusion Freeforming.

PubMed

Vaezi, Mohammad; Black, Cameron; Gibbs, David M R; Oreffo, Richard O C; Brady, Mark; Moshrefi-Torbati, Mohamed; Yang, Shoufeng

2016-05-26

Addition of bioactive materials such as calcium phosphates or Bioglass, and incorporation of porosity into polyetheretherketone (PEEK) has been identified as an effective approach to improve bone-implant interfaces and osseointegration of PEEK-based devices. In this paper, a novel production technique based on the extrusion freeforming method is proposed that yields a bioactive PEEK/hydroxyapatite (PEEK/HA) composite with a unique configuration in which the bioactive phase (i.e., HA) distribution is computer-controlled within a PEEK matrix. The 100% interconnectivity of the HA network in the biocomposite confers an advantage over alternative forms of other microstructural configurations. Moreover, the technique can be employed to produce porous PEEK structures with controlled pore size and distribution, facilitating greater cellular infiltration and biological integration of PEEK composites within patient tissue. The results of unconfined, uniaxial compressive tests on these new PEEK/HA biocomposites with 40% HA under both static and cyclic mode were promising, showing the composites possess yield and compressive strength within the range of human cortical bone suitable for load bearing applications. In addition, preliminary evidence supporting initial biological safety of the new technique developed is demonstrated in this paper. Sufficient cell attachment, sustained viability in contact with the sample over a seven-day period, evidence of cell bridging and matrix deposition all confirmed excellent biocompatibility.

21 CFR 888.3360 - Hip joint femoral (hemi-hip) metallic cemented or uncemented prosthesis.

Code of Federal Regulations, 2011 CFR

2011-04-01

... designs which are intended to be fixed to the bone with bone cement (§ 888.3027) as well as designs which have large window-like holes in the stem of the device and which are intended for use without bone cement. However, in these latter designs, fixation of the device is not achieved by means of bone...

21 CFR 888.3360 - Hip joint femoral (hemi-hip) metallic cemented or uncemented prosthesis.

Code of Federal Regulations, 2014 CFR

2014-04-01

... designs which are intended to be fixed to the bone with bone cement (§ 888.3027) as well as designs which have large window-like holes in the stem of the device and which are intended for use without bone cement. However, in these latter designs, fixation of the device is not achieved by means of bone...

21 CFR 888.3360 - Hip joint femoral (hemi-hip) metallic cemented or uncemented prosthesis.

Code of Federal Regulations, 2012 CFR

2012-04-01

... designs which are intended to be fixed to the bone with bone cement (§ 888.3027) as well as designs which have large window-like holes in the stem of the device and which are intended for use without bone cement. However, in these latter designs, fixation of the device is not achieved by means of bone...

21 CFR 888.3360 - Hip joint femoral (hemi-hip) metallic cemented or uncemented prosthesis.

Code of Federal Regulations, 2013 CFR

2013-04-01

... designs which are intended to be fixed to the bone with bone cement (§ 888.3027) as well as designs which have large window-like holes in the stem of the device and which are intended for use without bone cement. However, in these latter designs, fixation of the device is not achieved by means of bone...

21 CFR 888.3360 - Hip joint femoral (hemi-hip) metallic cemented or uncemented prosthesis.

Code of Federal Regulations, 2010 CFR

2010-04-01

... designs which are intended to be fixed to the bone with bone cement (§ 888.3027) as well as designs which have large window-like holes in the stem of the device and which are intended for use without bone cement. However, in these latter designs, fixation of the device is not achieved by means of bone...

Contact damage failure analyses of fretting wear behavior of the metal stem titanium alloy-bone cement interface.

PubMed

Zhang, Lanfeng; Ge, Shirong; Liu, Hongtao; Wang, Qingliang; Wang, Liping; Xian, Cory J

2015-11-01

Although cemented titanium alloy is not favored currently in the Western world for its poor clinical and radiography outcomes, its lower modulus of elasticity and good biocompatibility are instrumental for its ability supporting and transforming physical load, and it is more suitable for usage in Chinese and Japanese populations due to their lower body weights and unique femoral characteristics. Through various friction tests of different cycles, loads and conditions and by examining fretting hysteresis loops, fatigue process curves and wear surfaces, the current study investigated fretting wear characteristics and wear mechanism of titanium alloy stem-bone cement interface. It was found that the combination of loads and displacement affected the wear quantity. Friction coefficient, which was in an inverse relationship to load under the same amplitude, was proportional to amplitudes under the same load. Additionally, calf serum was found to both lubricate and erode the wear interface. Moreover, cement fatigue contact areas appeared black/oxidative in dry and gruel in 25% calf serum. Fatigue scratches were detected within contact areas, and wear scars were found on cement and titanium surfaces, which were concave-shaped and ring concave/ convex-shaped, respectively. The coupling of thermoplastic effect and minimal torque damage has been proposed to be the major reason of contact damage. These data will be important for further studies analyzing metal-cement interface failure performance and solving interface friction and wear debris production issues. Copyright © 2015 Elsevier Ltd. All rights reserved.

Revision total hip arthroplasty: the femoral side using cemented implants.

PubMed

Holt, Graeme; Hook, Samantha; Hubble, Matthew

2011-02-01

Advances in surgical technique and implant technology have improved the ten-year survival after primary total hip arthroplasty (THA). Despite this, the number of revision procedures has been increasing in recent years, a trend which is predicted to continue into the future. Revision THA is a technically demanding procedure often complicated by a loss of host bone stock which may be compounded by the need to remove primary implants. Both cemented and uncemented implant designs are commonly used in the United Kingdom for primary and revision THA and much controversy still exists as to the ideal method of stem fixation. In this article we discuss revision of the femur using cemented components during revision THA. We focus on three clinical scenarios including femoral cement-in-cement revision where the primary femoral cement-bone interface remains well fixed, femoral cement-in-cement revision for peri-prosthetic femoral fractures, and femoral impaction grafting. We discuss the clinical indications, surgical techniques and clinical outcomes for each of these procedures.

Do dynamic cement-on-cement knee spacers provide better function and activity during two-stage exchange?

PubMed

Jaekel, David J; Day, Judd S; Klein, Gregg R; Levine, Harlan; Parvizi, Javad; Kurtz, Steven M

2012-09-01

Implantation of an antibiotic bone cement spacer is used to treat infection of a TKA. Dynamic spacers fashioned with cement-on-cement articulating surfaces potentially facilitate patient mobility and reduce bone loss as compared with their static counterparts, while consisting of a biomaterial not traditionally used for load-bearing articulations. However, their direct impact on patient mobility and wear damage while implanted remains poorly understood. We characterized patient activity, surface damage, and porous structure of dynamic cement-on-cement spacers. We collected 22 dynamic and 14 static knee antibiotic cement spacers at revision surgeries at times ranging from 0.5 to 13 months from implantation. For these patients, we obtained demographic data and UCLA activity levels. We characterized surface damage using the Hood damage scoring method and used micro-CT analysis to observe the internal structure, cracking, and porosity of the cement. The average UCLA score was higher for patients with dynamic spacers than for patients with static spacers, with no differences in BMI or age. Burnishing was the only prevalent damage mode on all the bearing surfaces. Micro-CT analysis revealed the internal structure of the spacers was porous and highly inhomogeneous, including heterogeneous dispersion of radiopaque material and cavity defects. The average porosity was 8% (range, 1%-29%) and more than ½ of the spacers had pores greater than 1 mm in diameter. Our observations suggest dynamic, cement-on-cement spacers allow for increased patient activity without catastrophic failure. Despite the antibiotic loading and internal structural inhomogeneity, burnishing was the only prevalent damage mode that could be consistently classified with no evidence of fracture or delamination. The porous structure of the spacers varied highly across the surfaces without influencing the material failure.

Advantageous new conic cannula for spine cement injection.

PubMed

González, Sergio Gómez; Vlad, María Daniela; López, José López; Aguado, Enrique Fernández

2014-09-01

Experimental study to characterize the influence of the cannula geometry on both, the pressure drop and the cement flow velocity established along the cannula. To investigate how the new experimental geometry of cannulas can affect the extravertebral injection pressure and the velocity profiles established along the cannula during the injection process. Vertebroplasty procedure is being used to treat vertebral compression fractures. Vertebra infiltration is favored by the use of suitable: (1) syringes or injector devices; (2) polymer or ceramic bone cements; and (3) cannulas. However, the clinical use of ceramic bone cement has been limited due to press-filtering problems. Thus, new approaches concerning the cannula geometry are needed to minimize the press-filtering of calcium phosphate-based bone cements and thereby broaden its possible applications. Straight, conic, and combined conic-straight new cannulas with different proximal and distal both length and diameter ratios were drawn with computer-assisted design software. The new geometries were theoretically analyzed by: (1) Hagen-Poisseuille law; and (2) computational fluid dynamics. Some experimental models were manufactured and tested for extrusion in order to confirm and further advance the theoretical results. The results confirm that the totally conic cannula model, having proximal to distal diameter ratio equal 2, requires the lowest injection pressure. Furthermore, its velocity profile showed no discontinuity at all along the cannula length, compared with other known combined proximal and distal straight cannulas, where discontinuity was produced at the proximal-distal transition zone. The conclusion is that the conic cannulas: (a) further reduced the extravertebral pressure during the injection process; (b) showed optimum fluid flow velocity profiles to minimize filter-pressing problems, especially when ceramic cements are used; and (c) can be easily manufactured. In this sense, the new conic cannulas

3D bioprinting of methacrylated hyaluronic acid (MeHA) hydrogel with intrinsic osteogenicity.

PubMed

Poldervaart, Michelle T; Goversen, Birgit; de Ruijter, Mylene; Abbadessa, Anna; Melchels, Ferry P W; Öner, F Cumhur; Dhert, Wouter J A; Vermonden, Tina; Alblas, Jacqueline

2017-01-01

In bone regenerative medicine there is a need for suitable bone substitutes. Hydrogels have excellent biocompatible and biodegradable characteristics, but their visco-elastic properties limit their applicability, especially with respect to 3D bioprinting. In this study, we modified the naturally occurring extracellular matrix glycosaminoglycan hyaluronic acid (HA), in order to yield photo-crosslinkable hydrogels with increased mechanical stiffness and long-term stability, and with minimal decrease in cytocompatibility. Application of these tailor-made methacrylated hyaluronic acid (MeHA) gels for bone tissue engineering and 3D bioprinting was the subject of investigation. Visco-elastic properties of MeHA gels, measured by rheology and dynamic mechanical analysis, showed that irradiation of the hydrogels with UV light led to increased storage moduli and elastic moduli, indicating increasing gel rigidity. Subsequently, human bone marrow derived mesenchymal stromal cells (MSCs) were incorporated into MeHA hydrogels, and cell viability remained 64.4% after 21 days of culture. Osteogenic differentiation of MSCs occurred spontaneously in hydrogels with high concentrations of MeHA polymer, in absence of additional osteogenic stimuli. Addition of bone morphogenetic protein-2 (BMP-2) to the culture medium further increased osteogenic differentiation, as evidenced by increased matrix mineralisation. MeHA hydrogels demonstrated to be suitable for 3D bioprinting, and were printed into porous and anatomically shaped scaffolds. Taken together, photosensitive MeHA-based hydrogels fulfilled our criteria for cellular bioprinted bone constructs within a narrow window of concentration.

3D bioprinting of methacrylated hyaluronic acid (MeHA) hydrogel with intrinsic osteogenicity

PubMed Central

Poldervaart, Michelle T.; Goversen, Birgit; de Ruijter, Mylene; Abbadessa, Anna; Melchels, Ferry P. W.; Öner, F. Cumhur; Dhert, Wouter J. A.; Vermonden, Tina

2017-01-01

In bone regenerative medicine there is a need for suitable bone substitutes. Hydrogels have excellent biocompatible and biodegradable characteristics, but their visco-elastic properties limit their applicability, especially with respect to 3D bioprinting. In this study, we modified the naturally occurring extracellular matrix glycosaminoglycan hyaluronic acid (HA), in order to yield photo-crosslinkable hydrogels with increased mechanical stiffness and long-term stability, and with minimal decrease in cytocompatibility. Application of these tailor-made methacrylated hyaluronic acid (MeHA) gels for bone tissue engineering and 3D bioprinting was the subject of investigation. Visco-elastic properties of MeHA gels, measured by rheology and dynamic mechanical analysis, showed that irradiation of the hydrogels with UV light led to increased storage moduli and elastic moduli, indicating increasing gel rigidity. Subsequently, human bone marrow derived mesenchymal stromal cells (MSCs) were incorporated into MeHA hydrogels, and cell viability remained 64.4% after 21 days of culture. Osteogenic differentiation of MSCs occurred spontaneously in hydrogels with high concentrations of MeHA polymer, in absence of additional osteogenic stimuli. Addition of bone morphogenetic protein-2 (BMP-2) to the culture medium further increased osteogenic differentiation, as evidenced by increased matrix mineralisation. MeHA hydrogels demonstrated to be suitable for 3D bioprinting, and were printed into porous and anatomically shaped scaffolds. Taken together, photosensitive MeHA-based hydrogels fulfilled our criteria for cellular bioprinted bone constructs within a narrow window of concentration. PMID:28586346

Correlation of pull-out strength of cement-augmented pedicle screws with CT-volumetric measurement of cement.

PubMed

Fölsch, Christian; Goost, Hans; Figiel, Jens; Paletta, Jürgen R J; Schultz, Wolfgang; Lakemeier, Stefan

2012-12-01

Cement augmentation of pedicle screws increases fixation strength in an osteoporotic spine. This study was designed to determine the cement distribution and the correlation between the pull-out strength of the augmented screw and the cement volume within polyurethane (PU) foam. Twenty-eight cannulated pedicle screws (6×45 mm) (Peter Brehm, Erlangen, Germany) with four holes at the distal end of the screw were augmented with the acrylic Stabilit ER Bone Cement Vertebral Augmentation System (DFine Inc., San Jose, CA, USA) and implanted into open-cell rigid PU foam (Pacific Research Laboratories, Vashon Island, WA, USA) with a density of 0.12 g/cm3, resembling severe osteoporosis. Volumetric measurement of the cement with consideration of the distribution around the screws was done with multislice computed tomography scan (Somatom Definition, Siemens, Erlangen, Germany). Pull-out strength was tested with a servohydraulic system (MTS System Corporation, Eden Prairie, MN, USA), and nonaugmented screws served as control. Pearson's correlation coefficient with significance level α=0.05 and one-way analysis of variance test were used. We found a high (r=0.88) and significant (p<0.01) correlation between the cement volume and the pull-out strength, which increased by more than 5-fold with a volume of 3 ml. The correlation appeared linear at least up to 4 ml cement volume and failure always occurred at the cement-bone interface. The cement distribution was symmetric and circular around the most proximal hole, with a distance of 14 mm from the tip, and nearly 90% of the cement was found 6 mm distal and cranial to it. The 95% confidence interval for the relative amount of cement was 37%-41% within 2 mm of the most proximal hole. Compared with the control, a cement volume between 2.0 and 3.0 ml increased the pull-out strength significantly and is relevant for clinical purposes, whereas a volume of 0.5 ml did not. A cement volume beyond 3.0 ml should further increase the pull

Evaluation of Heat Transfer to the Implant-Bone Interface During Removal of Metal Copings Cemented onto Titanium Abutments.

PubMed

Cakan, Umut; Cakan, Murat; Delilbasi, Cagri

2016-01-01

The aim of this investigation was to measure the temperature increase due to heat transferred to the implant-bone interface when the abutment screw channel is accessed or a metal-ceramic crown is sectioned buccally with diamond or tungsten carbide bur using an air rotor, with or without irrigation. Cobalt-chromium copings were cemented onto straight titanium abutments. The temperature changes during removal of the copings were recorded over a period of 1 minute. The sectioning of coping with diamond bur and without water irrigation generated the highest temperature change at the cervical part of the implant. Both crown removal methods resulted in an increase in temperature at the implant-bone interface. However, this temperature change did not exceed 47°C, the potentially damaging threshold for bone reported in the literature.

Reconstruction of large cranial defect with alloplastic material (bone cement-cold cure polymethyl-methacrylate resin).

PubMed

Hallur, Neelakamal; Goudar, Gayatri; Sikkerimath, Basavaraj; Gudi, Santosh S; Patil, Ravi S

2010-06-01

A 40-years-old male patient reported to our department with a chief complaint of persistent palatal fluid discharge and large depressed forehead defect. He gave a history of trauma 20 months back due to head on collision to electric pole and underwent surgery twice for open reduction and fixation of facial skeletal fractures. After 9 months of surgery again a third surgery was performed for the removal of frontal bone due to infection and osteomyelitis at the same site. Extra-oral examination revealed a large fronto-cranial defect extending from superior border of frontal bone to supra-orbital margins bilaterally in length, and from frontal right lateral to frontal left lateral side in width, measuring 8.0 cm in length, 10.5 cm in width and 1.5 to 2.0 cm in depth. Intra-oral sinus fluid discharge was from left posterior palatal region. Preoperative CT was taken and reconstruction of fronto-cranial defect was successfully performed with bone cement. Alloplastic implant reconstruction achieved an excellent esthetic result without any complications.

Effect of Poly(Vinyl Alcohol) Addition on the Properties of Hydrothermal Derived Calcium Phosphate Cement for Bone Filling Materials

NASA Astrophysics Data System (ADS)

Razali, N. N.; Sopyan, I.; Mel, M.; Salleh, H. M.; Rahman, M. M.; Singh, R.

2017-06-01

The effect of addition of poly(vinyl alcohol) on hydrothermal derived calcium phosphate cement has been studied. The precursors used to prepare the cement were calcium oxide (CaO) and ammonium dihydrogen phosphate (NH4H2PO4); the reaction was conducted in water at 80-100°C. To improve properties of CPC, poly(vinyl alcohol) (PVA) of 1wt% and 2wt% was added to the liquid phase of CPC and the results were compared to CPC without PVA addition. The addition of PVA was proved to bring remarkable effects on cohesion, setting time and mechanical strength of CPC which make it suitable physically for injectable bone filler applications.

[Experimental study of canine bone marrow mesenchymal stem cells combined with calcium phosphate cement for repair of mandibular bone defects in Beagle dogs].

PubMed

Hu, Yi-cheng; Liu, Xin; Shen, Ji-jia; He, Jia-cai; Chen, Qiao-er

2014-08-01

To evaluate the effects of bone marrow mesenchymal stem cells (BMSCs) combined with calcium phosphate cement (CPC) scaffold for repair of mandibular defect in Beagle dogs. BMSCs were isolated from Beagle dogs and cultured in DMEM plus 10% FBS. The induction effect was determined using alizarin red staining or alkaline phosphate staining at 14-day of culture. BMSCs were added to the CPC scaffold for animal experiments. In vivo, three critical size bone defects were surgically created in each side of the mandible. The bone defects were repaired with BMSCs-CPC (scaffolds with composite seeding cells), CPC (scaffold alone) or no materials (blank group). Two dogs were sacrificed at 4-week and 8-week after operation. Gross observation, X-ray imaging, histologic and histometric analyses were performed to evaluate the level of bone formation. Newly formed bones were detected within all defect sites after operation. The BMSCs-CPC group and CPC group showed increased bone formation compared with the blank group. The BMSCs-CPC group exhibited more bone formation and degradation of the material than the CPC group. The percentage of new bone in the BMSCs-CPC and CPC treated group were significantly higher than that in the control group (P<0.05), while the percentage of new bone in the BMSCs-CPC sites was higher than that in the CPC sites (P<0.01); the percentage of residual material in the BMSCs-CPC sites was lower than that in the CPC sites (P<0.01) 4 weeks and 8 weeks after operation. Using the theory of tissue engineering, BMSCs composite CPC compound is an effective method in promoting new bone regeneration, which has a positive influence on the bone space preservation.

Assessment of tricalcium phosphate/collagen (TCP/collagene)nanocomposite scaffold compared with hydroxyapatite (HA) on healing of segmental femur bone defect in rabbits.

PubMed

Mohseni, Mahmoud; Jahandideh, Alireza; Abedi, Gholamreza; Akbarzadeh, Abolfazl; Hesaraki, Saeed

2018-03-01

Bone regeneration is an important objective in clinical practice and has been used for different applications. The aim of this study was to evaluate the effectiveness of nanocomposite tricalcium phosphate (TCP)/collagen scaffolds combined with hydroxyapatite scaffold for bone healing in surgery of femoral defects in rabbits. In this study, 45 mature male New Zealand white rabbits between 6 and 8 months old and weighting between 3 and 3.5 kg were examined. Rabbits were divided into three groups. Surgical procedures were performed after intramuscular injection of Ketamine 10% (ketamine hydrochloride, 50 mg/kg) and Rompun 5% (xylazine, 5 mg/kg). Then an approximately 6 mm diameter-5 mm cylinder bone defect was created in the femur of one of the hind limbs. After inducing the surgical wound, all rabbits were coloured and randomly divided into three experimental groups of 15 animals each. Group 1 received pure medical nanocomposite TCP/collagen granules, group 2 received hydroxyapatite, and third group was a control group which received no treatment. Histopathological evaluation was performed on days 15, 30, and 45 after surgery. On days 15, 30, and 45 after surgery, the quantity and the velocity of stages of bone formation at the healing site in nanocomposite TCP/collagen group were better than HA and control groups and the quantity of newly formed lamellar bone at the healing site in nanocomposite TCP/collagen group were better than onward compared with HA and control groups. In conclusion, it seems that TCP/collagen nanocomposite has a significant role in the reconstruction of bone defects and can be used as scaffold in bone fractures.

Periodontal regeneration using an injectable bone cement combined with BMP-2 or FGF-2.

PubMed

Oortgiesen, Daniël A W; Walboomers, X Frank; Bronckers, Antonius L J J; Meijer, Gert J; Jansen, John A

2014-03-01

Periodontitis is a frequently diagnosed oral disease characterized by bone resorption and soft tissue loss around teeth. Unfortunately, currently available therapies only slow or arrest progress of the disease. Ideally, treatment of periodontal defects should be focused on complete regeneration of the lost tissues [(bone and periodontal ligament (PDL)]. As a result, this study used intrabony defects to evaluate the regenerative potential of an injectable macroporous calcium phosphate cement (CaP) in combination with bone morphogenetic protein-2 (BMP-2) or fibroblast growth factor-2 (FGF-2). After creating 30 periodontal defects in 15 Wistar rats, three treatment strategies were conducted: application of CaP only, CaP + BMP-2 and CaP + FGF-2. Animals were euthanized after 12 weeks and processed for histology and histomorphometry. Using CaP alone resulted in limited effects on PDL and bone healing. CaP + BMP-2 showed a good response for bone healing; a significant 2.4 fold increase in bone healing score was observed compared to CaP. However, for PDL healing, CaP + BMP-2 treatment showed no difference compared to the CaP group. The best results were observed with the combined treatment of CaP + FGF-2, which showed a significant 3.3 fold increase in PDL healing score compared to CaP + BMP-2 and a significant 2.6 fold increase compared to CaP. For bone healing, CaP +  FGF-2 showed a significant 1.9 fold increase compared to CaP but no significant difference was noted compared to the CaP + BMP-2 group. The combination of a topical application of FGF-2 and an injectable CaP seems to be a promising treatment modality for periodontal regeneration. Copyright © 2012 John Wiley & Sons, Ltd.

10-year results of a new low-monomer cement: follow-up of a randomized RSA study.

PubMed

Söderlund, Per; Dahl, Jon; Röhrl, Stephan; Nivbrant, Bo; Nilsson, Kjell G

2012-12-01

The properties and performance of a new low-monomer cement were examined in this prospective randomized, controlled RSA study. 5-year data have already been published, showing no statistically significant differences compared to controls. In the present paper we present the 10-year results. 44 patients were originally randomized to receive total hip replacement with a Lubinus SPII titanium-aluminum-vanadium stem cemented either with the new Cemex Rx bone cement or with control bone cement, Palacos R. Patients were examined using RSA, Harris hip score, and conventional radiographs. At 10 years, 33 hips could be evaluated clinically and 30 hips could be evaluated with RSA (16 Cemex and 14 Palacos). 9 patients had died and 4 patients were too old or infirm to be investigated. Except for 1 hip that was revised for infection after less than 5 years, no further hips were revised before the 10-year follow-up. There were no statistically significant clinical differences between the groups. The Cemex cement had magnitudes of migration similar to or sometimes lower than those of Palacos cement. In both groups, most hips showed extensive radiolucent lines, probably due to the use of titanium alloy stems. At 10 years, the Cemex bone cement tested performed just as well as the control (Palacos bone cement).

[Bone cement adhesion on ceramic surfaces - surface activation of retention surfaces of knee prostheses by atmospheric plasma versus thermal surface treatment].

PubMed

Marx, B; Marx, R; Reisgen, U; Wirtz, D

2015-04-01

CoCrMo alloys are contraindicated for allergy sufferers. For these patients, uncemented and cemented prostheses made of titanium alloy are indicated. Knee prostheses machined from that alloy, however, may have poor tribological behaviour, especially in relation to UHMWPE inlays. Therefore, for knee replacement cemented high-strength oxide ceramic prostheses are suitable for allergy sufferers and in cases of particle-induced aseptic loosening. For adhesion of bone cement, the ceramic surface, however, only exposes inefficient mechanical retention spots as compared with a textured metal surface. Undercuts generated by corundum blasting which in the short-term are highly efficient on a CoCrMo surface are not possible on a ceramic surface due to the brittleness of ceramics. Textures due to blasting may initiate cracks which will weaken the strength of a ceramic prosthesis. Due to the lack of textures mechanical retention is poor or even not existent. Micromotions are promoted and early aseptic loosening is predictable. Instead silicoating of the ceramic surface will allow specific adhesion and result in better hydrolytic stability of bonding thereby preventing early aseptic loosening. Silicoating, however, presupposes a clean and chemically active surface which can be achieved by atmospheric plasma or thermal surface treatment. In order to evaluate the effectiveness of silicoating the bond strengths of atmospheric plasma versus thermal surface treated and silicate layered ZPTA surfaces were compared with "as-fired" surfaces by utilising TiAlV probes (diameter 6 mm) for traction-adhesive strength tests. After preparing samples for traction-adhesive strength tests (sequence: ceramic substrate, silicate and silane, protective lacquer [PolyMA], bone cement, TiAlV probe) they were aged for up to 150 days at 37 °C in Ringer's solution. The bond strengths observed for all ageing intervals were well above 20 MPa and much higher and more hydrolytically stable for

The effect of cup outer sizes on the contact mechanics and cement fixation of cemented total hip replacements.

PubMed

Hua, Xijin; Li, Junyan; Wang, Ling; Wilcox, Ruth; Fisher, John; Jin, Zhongmin

2015-10-01

One important loosening mechanism of the cemented total hip arthroplasty is the mechanical overload at the bone-cement interface and consequent failure of the cement fixation. Clinical studies have revealed that the outer diameter of the acetabular component is a key factor in influencing aseptic loosening of the hip arthroplasty. The aim of the present study was to investigate the influence of the cup outer diameter on the contact mechanics and cement fixation of a cemented total hip replacement (THR) with different wear penetration depths and under different cup inclination angles using finite element (FE) method. A three-dimensional FE model was developed based on a typical Charnley hip prosthesis. Two acetabular cup designs with outer diameters of 40 and 43 mm were modelled and the effect of cup outer diameter, penetration depth and cup inclination angle on the contact mechanics and cement fixation stresses in the cemented THR were studied. The results showed that for all penetration depths and cup inclination angles considered, the contact mechanics in terms of peak von Mises stress in the acetabular cup and peak contact pressure at the bearing surface for the two cup designs were similar (within 5%). However, the peak von Mises stress, the peak maximum principal stress and peak shear stress in the cement mantle at the bone-cement interface for the 43 mm diameter cup design were predicted to be lower compared to those for the 40 mm diameter cup design. The differences were predicted to be 15-19%, 15-22% and 18-20% respectively for different cup penetration depths and inclination angles, which compares to the clinical difference of aseptic loosening incidence of about 20% between the two cup designs. Copyright © 2015 IPEM. Published by Elsevier Ltd. All rights reserved.

Cemental tear: To know what we have neglected in dental practice.

PubMed

Jeng, Po-Yuan; Luzi, Arlinda Luzi; Pitarch, Rocio Marco; Chang, Mei-Chi; Wu, Yu-Hsueh; Jeng, Jiiang-Huei

2018-04-01

Cemental tear is a special kind of root surface fracture, contributing to periodontal and periapical breakdown. However, it is a challenge for doctors to diagnose, resulting in delayed or improper treatment. We reviewed the predisposing factors, location, radiographic/clinical characteristics, diagnosis and treatments of cemental tears. From the literature, patients with cemental tear were mainly males, over 60 year-old. Possible predisposing factors include gender, age, tooth type, traumatic occlusal force and vital teeth. Cemental tears were common in upper and lower anterior teeth, single or multiple, and can be present in cervical, middle and apical third of roots. Morphology of cemental tears can be either piece-shaped or U-shaped. Clinically, cemental tear shows a unitary periodontal pocket and signs/symptoms mimicking localized periodontitis, apical periodontitis and vertical root fractures. Treatment of cemental tears include scaling, root planning, root canal treatment, periodontal/periapical surgery, guided tissue regeneration, bone grafting, and intentional replantation. Recurrence of cemental tear is possible especially when the fracture involves root apex. Extraction is recommended for teeth with poor prognosis. In conclusion, cemental tears can involve both periodontal and periapical area. Dentists should understand the predisposing factors and clinical features of cemental tears for early diagnosis/treatment to prevent bone loss/tooth extraction. Copyright © 2017. Published by Elsevier B.V.

Presentation and management of symptomatic central bone cement embolization.

PubMed

Barakat, Ahmed Samir; Owais, Tamer; Alhashash, Mohamed; Shousha, Mootaz; El Saghir, Hesham; Lauer, Bernward; Boehm, Heinrich

2017-08-18

With more cement augmentation procedures done, the occurrence of serious complications is also expected to rise. Symptomatic central cement embolization is a rare but very serious complication. Moreover, the pathophysiology and treatment of intrathoracic cement embolism remain controversial. In this case series, we are trying to identify various presentations and suggest our emergent management scheme for symptomatic central cement embolization. Retrospective case series of nine patients with symptomatic central cement embolism identified after vertebroplasty with 24 months of follow-up. Level IV. The degree of dyspnea measured by the New York Heart Association (NYHA) score and/or death related to cement embolism induced cardio/respiratory failure at the final follow-up at 24 months. The nine patients, eight females, and one male had a mean age of 70.25 years (range 65-78 years) and were operated between January 2004 and December 2014. They had percutaneous vertebroplasty for osteoporotic non-traumatic and malignant vertebral collapse of dorsal and lumbar vertebrae. Post-vertebroplasty dyspnea and stitching chest pain were striking in the nine patients. After exclusion of cardiac ischemia and medical pulmonary causes for dyspnea, we identified radiopaque lesions on the chest X-ray. Further echocardiography and high-resolution chest CT were performed for optimal localization. Emergent heart surgery was performed in two patients: interventional therapy was conducted in one patient, while the remaining six patients were conservatively treated by anticoagulation. The management decision was taken in the setting of an interdisciplinary meeting depending on localization, fragmentation, and clinical status. All patients of this series showed gradual improvement and an uneventful hospital stay. During our 24-month follow-up phase, eight patients showed no subsequent cardiological and/or respiratory symptoms (NYHA I). However, one mortality due to advanced malignancy

Antibiotic stability over six weeks in aqueous solution at body temperature with and without heat treatment that mimics the curing of bone cement

PubMed Central

Samara, E.; Decosterd, L. A.; Richards, R. G.; Gautier, E.; Wahl, P.

2017-01-01

Objectives Thermal stability is a key property in determining the suitability of an antibiotic agent for local application in the treatment of orthopaedic infections. Despite the fact that long-term therapy is a stated goal of novel local delivery carriers, data describing thermal stability over a long period are scarce, and studies that avoid interference from specific carrier materials are absent from the orthopaedic literature. Methods In this study, a total of 38 frequently used antibiotic agents were maintained at 37°C in saline solution, and degradation and antibacterial activity assessed over six weeks. The impact of an initial supplementary heat exposure mimicking exothermically curing bone cement was also tested as this material is commonly used as a local delivery vehicle. Antibiotic degradation was assessed by liquid chromatography coupled to mass spectrometry, or by immunoassays, as appropriate. Antibacterial activity over time was determined by the Kirby-Bauer disk diffusion assay. Results The heat exposure mimicking curing bone cement had minimal effect on stability for most antibiotics, except for gentamicin which experienced approximately 25% degradation as measured by immunoassay. Beta-lactam antibiotics were found to degrade quite rapidly at 37°C regardless of whether there was an initial heat exposure. Excellent long-term stability was observed for aminoglycosides, glycopeptides, tetracyclines and quinolones under both conditions. Conclusions This study provides a valuable dataset for orthopaedic surgeons considering local application of antibiotics, and for material scientists looking to develop next-generation controlled or extended-release antibiotic carriers. Cite this article: E. Samara, T. F. Moriarty, L. A. Decosterd, R. G. Richards, E. Gautier, P. Wahl. Antibiotic stability over six weeks in aqueous solution at body temperature with and without heat treatment that mimics the curing of bone cement. Bone Joint J 2017;6:296–306. DOI: 10

Magnesium modification of a calcium phosphate cement alters bone marrow stromal cell behavior via an integrin-mediated mechanism.

PubMed

Zhang, Jing; Ma, Xiaoyu; Lin, Dan; Shi, Hengsong; Yuan, Yuan; Tang, Wei; Zhou, Huanjun; Guo, Han; Qian, Jiangchao; Liu, Changsheng

2015-06-01

The chemical composition, structure and surface characteristics of biomaterials/scaffold can affect the adsorption of proteins, and this in turn influences the subsequent cellular response and tissue regeneration. With magnesium/calcium phosphate cements (MCPC) as model, the effects of magnesium (Mg) on the initial adhesion and osteogenic differentiation of bone marrow stromal cells (BMSCs) as well as the underlying mechanism were investigated. A series of MCPCs with different magnesium phosphate cement (MPC) content (0∼20%) in calcium phosphate cement (CPC) were synthesized. MCPCs with moderate proportion of MPC (5% and 10%, referred to as 5MCPC and 10MCPC) were found to effectively modulate the orientation of the adsorbed fibronectin (Fn) to exhibit enhanced receptor binding affinity, and to up-regulate integrin α5β1 expression of BMSCs, especially for 5MCPC. As a result, the attachment, morphology, focal adhesion formation, actin filaments assembly and osteogenic differentiation of BMSCs on 5MCPC were strongly enhanced. Further in vivo experiments confirmed that 5MCPC induced promoted osteogenesis in comparison to ot her CPC/MCPCs. Our results also suggested that the Mg on the underlying substrates but not the dissolved Mg ions was the main contributor to the above positive effects. Based on these results, it can be inferred that the specific interaction of Fn and integrin α5β1 had predominant effect on the MCPC-induced enhanced cellular response of BMSCs. These results provide a new strategy to regulate BMSCs adhesion and osteogenic differentiation by adjusting the Mg/Ca content and distribution in CPC, guiding the development of osteoinductive scaffolds for bone tissue regeneration. Copyright © 2015 Elsevier Ltd. All rights reserved.

Sr, Mg cosubstituted HA porous macro-granules: potentialities as resorbable bone filler with antiosteoporotic functions.

PubMed

Landi, Elena; Uggeri, Jacopo; Medri, Valentina; Guizzardi, Stefano

2013-09-01

Porous macro-granules of nanostructured apatite with Ca ions partially cosubstituted with Mg and Sr ions in different ratios (SrMgHAs), were synthesized at 37°C and compared with Mg and/or Sr free apatites (MgHAs and HA). Strontium improved the Mg substitution extent in the apatite and the chemical-physical and thermal stability of the resulting cosubstituted apatite. Porous macro-granules of 400-600 micron with selected composition were tested for the ionic release in synthetic body fluid and the data were related with the results of preliminary cell investigation in vitro. As compared to the corresponding Sr-free granulate, the SrMgHA could be exploited to prolong the beneficial Mg release during the bone regeneration process. In addition the contemporary in situ supply of Sr, an antiosteoporotic and anticarie ion, could influence the quality of new hard tissues. The ionic multirelease created a more favorable environment for human osteoblasts, demonstrated by a proliferative effect for each dose tested in the range 0.1-10 mg/mL. Copyright © 2013 Wiley Periodicals, Inc.

Mechanical aspects of degree of cement bonding and implant wedge effect.

PubMed

Yoon, Yong-San; Oxland, Thomas R; Hodgson, Antony J; Duncan, Clive P; Masri, Bassam A; Choi, Donok

2008-11-01

The degree of bonding between the femoral stem and cement in total hip replacement remains controversial. Our objective was to determine the wedge effect by debonding and stem taper angle on the structural behavior of axisymmetric stem-cement-bone cylinder models. Stainless steel tapered plugs with a rough (i.e. bonded) or smooth (i.e. debonded) surface finish were used to emulate the femoral stem. Three different stem taper angles (5 degrees , 7.5 degrees , 10 degrees ) were used for the debonded constructs. Non-tapered and tapered (7.5 degrees ) aluminum cylindrical shells were used to emulate the diaphyseal and metaphyseal segments of the femur. The cement-aluminum cylinder interface was designed to have a shear strength that simulated bone-cement interfaces ( approximately 8MPa). The test involved applying axial compression at a rate of 0.02mm/s until failure. Six specimens were tested for each combination of the variables. Finite element analysis was used to enhance the understanding of the wedge effect. The debonded stems sustained about twice as much load as the bonded stem, regardless of taper angle. The metaphyseal model carried 35-50% greater loads than the diaphyseal models and the stem taper produced significant differences. Based on the finite element analysis, failure was most probably by shear at the cement-bone interface. Our results in this simplified model suggest that smooth (i.e. debonded) stems have greater failure loads and will incur less slippage or shear failure at the cement-bone interface than rough (i.e. bonded) stems.

Design and biomechanical evaluation of a cementable endosteal blade implant.

PubMed

Pugh, J; Weiss, C; Weiss, F; Malkin, D

1976-07-01

A cementable endosteal blade implant has been developed and evaluated. Inherent in the design are the following factors: minimization of stress concentrators, ease of implantation, and high resistance to loosening. Other potential advantages of this design as compared with conventional endosteal blade implants include reduced hazards of postoperative infection and reduced likelihood of metallic corrosion. Six conventional endosteal implants and six cementable implants were installed in steer mandibles using standard dental surgical techniques and Simplex-brand methyl methacrylate bone cement. They were loaded in uniaxial compresstion at a loading rate of 0.0122 in./min. the stiffness (S), deformation at 900-lb load (D900), proportional limil (PL), and load at 0.04 in. deformation (L0.04) were calculated for each test. The cementable design showed a twofold increase in stiffness, only 17% of the deformation at 900lb, more than twice the proportional limit, and at least twice the load at 0.04 in. deformation when compared with similar values for the conventional endosteal implants. This study reveals that, in addition to being unstable in bone, conventional endosteal implants are also unstable when used with acrylic bone cement. The new design should eliminate most of the problems associated with endosteal blade implantation.

21 CFR 888.3353 - Hip joint metal/ceramic/polymer semi-constrained cemented or nonporous uncemented prosthesis.

Code of Federal Regulations, 2011 CFR

2011-04-01

... fixed in the intramedullary canal of the femur by impaction with or without use of bone cement. The... nonporous metal alloys, and used with or without bone cement. (b) Classification. Class II. [54 FR 48239...

21 CFR 888.3353 - Hip joint metal/ceramic/polymer semi-constrained cemented or nonporous uncemented prosthesis.

Code of Federal Regulations, 2013 CFR

2013-04-01

... fixed in the intramedullary canal of the femur by impaction with or without use of bone cement. The... nonporous metal alloys, and used with or without bone cement. (b) Classification. Class II. [54 FR 48239...

21 CFR 888.3353 - Hip joint metal/ceramic/polymer semi-constrained cemented or nonporous uncemented prosthesis.

Code of Federal Regulations, 2014 CFR

2014-04-01

... fixed in the intramedullary canal of the femur by impaction with or without use of bone cement. The... nonporous metal alloys, and used with or without bone cement. (b) Classification. Class II. [54 FR 48239...

21 CFR 888.3353 - Hip joint metal/ceramic/polymer semi-constrained cemented or nonporous uncemented prosthesis.

Code of Federal Regulations, 2012 CFR

2012-04-01

... fixed in the intramedullary canal of the femur by impaction with or without use of bone cement. The... nonporous metal alloys, and used with or without bone cement. (b) Classification. Class II. [54 FR 48239...

21 CFR 888.3353 - Hip joint metal/ceramic/polymer semi-constrained cemented or nonporous uncemented prosthesis.

Code of Federal Regulations, 2010 CFR

2010-04-01

... fixed in the intramedullary canal of the femur by impaction with or without use of bone cement. The... nonporous metal alloys, and used with or without bone cement. (b) Classification. Class II. [54 FR 48239...

Study on clinical application of nano-hydroxyapatite bone in bone defect repair.

PubMed

Zhu, Weimin; Wang, Daping; Xiong, Jianyi; Liu, Jianquan; You, Wei; Huang, Jianghong; Duan, Li; Chen, Jielin; Zeng, Yanjun

2015-01-01

To study the clinical effect of bone defect treated with nano-hydroxyapatite(Nano-HA) artificial bone. From September 2009 to June 2012, 27 cases of bone defect were analyzed retrospectively. The position of bone defect included humerus, radius, ulna, femur, tibia and calcaneus. The range of bone defect was from 0.3 × 1.0 cm to 3 × 6.5 cm. Among them, there were 22 cases with fractures and 5 cases with tumors. All patients were treated with Nano-HA artificial bone. The ability of bone defect repair was evaluated by X-ray exams performed preoperatively and postoperatively. HSS scores were adopted for final evaluation at the latest follow-up. The patients were followed up from 11 to 26 months (average of 18.5 months). No general side effects occurred. X-ray photo showed an integrity interface between Nano-HA and bone. Primary healing was obtained in all cases without any complication. The Nano-HA artificial bone had a good biocompatibility and could be an ideal artificial bone in the reconstruction of bone defect.

Peri-Implantitis Associated with Type of Cement: A Retrospective Analysis of Different Types of Cement and Their Clinical Correlation to the Peri-Implant Tissue.

PubMed

Korsch, Michael; Walther, Winfried

2015-10-01

The cementation of fixed implant-supported dental restorations involves the risk of leaving excess cement in the mouth which can promote biofilm formation in the peri-implant sulcus. As a result, an inflammation may develop. The aim of the present study was to investigate the clinical effect of two different luting cements on the peri-implant tissue. Within the scope of a retrospective clinical follow-up study, the prosthetic structures of 22 patients with 45 implants were revised. In all cases, a methacrylate cement (Premier Implant Cement [PIC], Premier® Dental Products Company, Plymouth Meeting, PA, USA) had been used for cementation. In 16 additional patients with 28 implants, the suprastructures were retained with a zinc oxide-eugenol cement (Temp Bond [TB], Kerr Sybron Dental Specialities, Glendora, CA, USA). These patients were evaluated in the course of routine treatment. In both populations, the retention time of the suprastructures was similar (TB 3.77 years, PIC 4.07 years). In the PIC cases, 62% of all implants had excess cement. In the TB cases, excess cement was not detectable on any of the implants. Bleeding on probing was significantly more frequent on implants cemented with PIC (100% with and 94% without excess cement) than on implants cemented with TB (46%). Pocket suppuration was observed on 89% of the PIC-cemented implants with excess cement (PIC without excess cement 24%), whereas implants with TB were not affected by it at all. The peri-implant bone loss was significantly greater in the PIC patients (with excess cement 1.37 mm, without excess cement 0.41 mm) than it was in the TB patients (0.07 mm). The frequency of undetected excess cement depends essentially on the type of cement used. Cements that tend to leave more undetected excess have a higher prevalence for peri-implant inflammation and cause a more severe peri-implant bone loss. © 2014 Wiley Periodicals, Inc.

Short-term implantation effects of a DCPD-based calcium phosphate cement.

PubMed

Frayssinet, P; Gineste, L; Conte, P; Fages, J; Rouquet, N

1998-06-01

Calcium phosphate cements can be handled in paste form and set in a wet medium after precipitation of calcium phosphate crystals in the implantation site. Depending on the products entering into the chemical reaction leading to the precipitation of calcium phosphates, different phases can be obtained with different mechanical properties, setting times and injectability. We tested a cement composed of a powder, containing beta-tricalcium phosphate (beta-TCP) and sodium pyrophosphate mixed with a solution of phosphoric and sulphuric acids. The cement set under a dicalcium phosphate dihydrate (DCPD)-based matrix containing beta-TCP particles. This was injected with a syringe into a defect drilled in rabbit condyles, the control being an identical defect left empty in the opposite condyle. The condyles were analysed histologically 2, 6 and 18 weeks after implantation. After injection into the bone defect the cement set and formed a porous calcium phosphate structure. Two different calcium phosphate phases with different solubility rates could be identified by scanning electron microscopy (SEM) observation. The less-soluble fragments could be degraded by cell phagocytosis in cell compartments of low pH or integrated in the newly formed bone matrix. The degradation rate of the material was relatively high but compatible with the ingrowth of bone trabeculae within the resorbing material. The ossification process was different from the creeping substitution occurring at the ceramic contact. Bone did not form directly at the cement surface following the differentiation of osteoblasts at the material surface. The trabeculae came to the material surface from the edges of the implantation site. Bone formation in the implantation site was significantly higher than in the control region during the first week of implantation. In conclusion, this material set in situ was well tolerated, inducing a mild foreign-body reaction, which did not impair its replacement by newly formed

3D artificial bones for bone repair prepared by computed tomography-guided fused deposition modeling for bone repair.

PubMed

Xu, Ning; Ye, Xiaojian; Wei, Daixu; Zhong, Jian; Chen, Yuyun; Xu, Guohua; He, Dannong

2014-09-10

The medical community has expressed significant interest in the development of new types of artificial bones that mimic natural bones. In this study, computed tomography (CT)-guided fused deposition modeling (FDM) was employed to fabricate polycaprolactone (PCL)/hydroxyapatite (HA) and PCL 3D artificial bones to mimic natural goat femurs. The in vitro mechanical properties, in vitro cell biocompatibility, and in vivo performance of the artificial bones in a long load-bearing goat femur bone segmental defect model were studied. All of the results indicate that CT-guided FDM is a simple, convenient, relatively low-cost method that is suitable for fabricating natural bonelike artificial bones. Moreover, PCL/HA 3D artificial bones prepared by CT-guided FDM have more close mechanics to natural bone, good in vitro cell biocompatibility, biodegradation ability, and appropriate in vivo new bone formation ability. Therefore, PCL/HA 3D artificial bones could be potentially be of use in the treatment of patients with clinical bone defects.

Migration of cemented femoral components after THR. Roentgen stereophotogrammetric analysis.

PubMed

Kiss, J; Murray, D W; Turner-Smith, A R; Bithell, J; Bulstrode, C J

1996-09-01

We studied the migration of 58 cemented Hinek femoral components for total hip replacement, using roentgen stereophotogrammetric analysis over four years. The implants migrated faster during the first year than subsequently, and the pattern of migration in the second period was very different. During the first year they subsided, tilted into varus and internally rotated. After this there was slow distal migration with no change in orientation. None of the prostheses has yet failed. The early migration is probably caused by resorption of bone damaged by surgical trauma or the heat generated by the polymerisation of bone cement. Later migration may be due to creep in the bone cement or the surrounding fibrous membrane. The prosthesis which we studied allows the preservation of some of the femoral neck, and comparison with published migration studies of the Charnley stem suggests that this decreases rotation and may help to prevent loosening.

Acceleration of bone regeneration by activating Wnt/β-catenin signalling pathway via lithium released from lithium chloride/calcium phosphate cement in osteoporosis

NASA Astrophysics Data System (ADS)

Li, Li; Peng, Xiaozhong; Qin, Yongbao; Wang, Renchong; Tang, Jingli; Cui, Xu; Wang, Ting; Liu, Wenlong; Pan, Haobo; Li, Bing

2017-03-01

By virtue of its excellent bioactivity and osteoconductivity, calcium phosphate cement (CPC) has been applied extensively in bone engineering. Doping a trace element into CPC can change physical characteristics and enhance osteogenesis. The trace element lithium has been demonstrated to stimulate the proliferation and differentiation of osteoblasts. We investigated the fracture-healing effect of osteoporotic defects with lithium-doped calcium phosphate cement (Li/CPC) and the underlying mechanism. Li/CPC bodies immersed in simulated body fluid converted gradually to hydroxyapatite. Li/CPC extracts stimulated the proliferation and differentiation of osteoblasts upon release of lithium ions (Li+) at 25.35 ± 0.12 to 50.74 ± 0.13 mg/l through activation of the Wnt/β-catenin pathway in vitro. We also examined the effect of locally administered Li+ on defects in rat tibia between CPC and Li/CPC in vivo. Micro-computed tomography and histological staining showed that Li/CPC had better osteogenesis by increasing bone mass and promoting repair in defects compared with CPC (P < 0.05). Li/CPC also showed better osteoconductivity and osseointegration. These findings suggest that local release of Li+ from Li/CPC may accelerate bone regeneration from injury through activation of the Wnt/β-catenin pathway in osteoporosis.

Interface activation and surface characteristics of Ti/TiN/HA coated sintered stainless steels

NASA Astrophysics Data System (ADS)

Choe, Han-Cheol; Ko, Yeong-Mu

2006-02-01

Interface activation and surface characteristics of Ti/TiN/HA film coated sintered stainless steels (SSS) have been investigated by electrochemical and biocompatibility tests. HA (hydroxyapatite), Ti, and Ti/TiN film coatings were applied using electron-beam deposition method (EB-PVD). Ti, Ti/TiN, and Ti/TiN/HA film coated surfaces and layers were investigated by SEM and XPS. The coated films showed micro-columnar structure, and Ti/TiN/HA films were denser than Ti or HA-only film. The corrosion resistance of the HA coating was similar to that of Ti/TiN/HA film coating when Cu content reached 4 wt.%, but the corrosion resistance of the HA coating decreased when Cu content increased from 4 wt.% in 0.9% NaCl solution. Therefore, HA-only coating could ensure corrosion resistance when Cu content does not exceed 4 wt.%. The results of biocompatibility tests of SSS on dogs showed that bone formation and biocompatibility were favorable when Cu content did not exceed 4 wt.%. The biocompatibility with bone was generally favorable in Ti/TiN/HA film coating and HA-only coating, while bone formation was somewhat faster for the HA film coated surface than for the Ti/TiN/HA film coating. Also, good cell growth and osseointegration without toxicity were observed.

An approximate model for cancellous bone screw fixation.

PubMed

Brown, C J; Sinclair, R A; Day, A; Hess, B; Procter, P

2013-04-01

This paper presents a finite element (FE) model to identify parameters that affect the performance of an improved cancellous bone screw fixation technique, and hence potentially improve fracture treatment. In cancellous bone of low apparent density, it can be difficult to achieve adequate screw fixation and hence provide stable fracture fixation that enables bone healing. Data from predictive FE models indicate that cements can have a significant potential to improve screw holding power in cancellous bone. These FE models are used to demonstrate the key parameters that determine pull-out strength in a variety of screw, bone and cement set-ups, and to compare the effectiveness of different configurations. The paper concludes that significant advantages, up to an order of magnitude, in screw pull-out strength in cancellous bone might be gained by the appropriate use of a currently approved calcium phosphate cement.

Bone Repair and Military Readiness

DTIC Science & Technology

2014-08-01

based resin superior to polymethyl methacrylate ( PMMA ) with many improved properties such as significantly less polymerization stress without an...in animal models. By addressing the shortcomings of current PMMA bone cement, the development of the novel silorane bone cement will result in a...and heat generation. We have developed a silorane based resin superior to polymethyl methacrylate ( PMMA ) with many improved properties such as

Fabrication and characterization of highly porous barium titanate based scaffold coated by Gel/HA nanocomposite with high piezoelectric coefficient for bone tissue engineering applications.

PubMed

Ehterami, Arian; Kazemi, Mansure; Nazari, Bahareh; Saraeian, Payam; Azami, Mahmoud

2018-03-01

It is well established that the piezoelectric effect plays an important physiological role in bone growth, remodeling and fracture healing. Barium titanate, as a well-known piezoelectric ceramic, is especially an attractive material as a scaffold for bone tissue engineering applications. In this regard, we tried to fabricate a highly porous barium titanate based scaffolds by foam replication method and polarize them by applying an external electric field. In order to enhance the mechanical and biological properties, polarized/non-polarized scaffolds were coated with gelatin and nanostructured HA and characterized for their morphologies, porosities, piezoelectric and mechanical properties. The results showed that the compressive strength and piezoelectric coefficient of porous scaffolds increased with the increase of sintering temperature. After being coated with Gel/HA nanocomposite, the interconnected porous structure and pore size of the scaffolds almost remain unchanged while the Gel/nHA-coated scaffolds exhibited enhanced compressive strength and elastic modulus compared with the uncoated samples. Also, the effect of polarizing and coating of optimal scaffolds on adhesion, viability, and proliferation of the MG63 osteoblast-like cell line was evaluated by scanning electron microscope (SEM) and MTT assay. The cell culture experiments revealed that developed scaffolds had good biocompatibility and cells were able to adhere, proliferate and migrate into pores of the scaffolds. Furthermore, cell density was significantly higher in the coated scaffolds at all tested time-points. These results indicated that highly porous barium titanate scaffolds coated with Gel/HA nanocomposite has great potential in tissue engineering applications for bone tissue repair and regeneration. Copyright © 2018 Elsevier Ltd. All rights reserved.

Cemented total knee replacement in 24 dogs: surgical technique, clinical results, and complications.

PubMed

Allen, Matthew J; Leone, Kendall A; Lamonte, Kimberly; Townsend, Katy L; Mann, Kenneth A

2009-07-01

To characterize the performance of cemented total knee replacement (TKR) in dogs. Preclinical research study. Skeletally mature, male Hounds (25-30 kg; n=24) with no preexisting joint pathology. Dogs had unilateral cemented TKR and were evaluated at 6, 12, 26, or 52 weeks (6 dogs/time point) by radiography, bone density analysis, visual gait assessment, and direct measurement of thigh circumference and stifle joint range of motion as indicators of functional recovery. At study end, the stability of the cemented tibial component was determined by destructive mechanical testing. Joint stability was excellent in 16 dogs (67%) and good in 8 dogs. None of the tibial components had evidence of migration or periprosthetic osteolysis whereas 1 femoral component was loose at 52 weeks. There was an early and significant decrease in tibial bone density, likely because of disuse of the operated limb. Dogs returned to full activity by 12 weeks. The tibial cement-bone interface maintained its strength over 52 weeks. Cement provides stable fixation of the tibial component in canine TKR. Cemented TKR yields adequate clinical function and stifle joint excursion in the dog. Clinical studies are needed to determine the long-term fate of cemented TKR implants, to assess the influence of implant design on implant fixation and wear, and to obtain objective functional data.

The Impact of Residual Subgingival Cement on Biological Complications Around Dental Implants: A Systematic Review.

PubMed

Quaranta, Alessandro; Lim, Zhuo Wei; Tang, Joyce; Perrotti, Vittoria; Leichter, Jonathan

2017-06-01

To perform a systematic review on the impact of residual subgingival cement on peri-implant diseases and crestal bone loss. MEDLINE, SCOPUS, ISI Web of Knowledge and Cochrane Central Register of Controlled Trials (CENTRAL) databases were used to identify articles published without time limits. A total of 6 articles were selected for a total of 389 patients (687 implants). The studies were heterogeneous and had a moderate-to-high risk of bias, but met the inclusion criteria. Four of 6 studies were published by the same research group and assessed similar populations over time. A positive relationship between residual cement and peri-implant inflammation was observed. Data on peri-implant probing depths and crestal bone loss were reported in 1 study. Residual subgingival cement seems to be strongly associated with peri-implant mucositis which is a risk factor for increased probing depths crestal bone loss and peri-implantitis. Zinc oxide eugenol cements should be preferred to resin cements especially in patients with a history of periodontitis.

Morphological and mechanical characterization of composite bone cement containing polymethylmethacrylate matrix functionalized with trimethoxysilyl and bioactive glass.

PubMed

Puska, Mervi; Moritz, Niko; Aho, Allan J; Vallittu, Pekka K

2016-06-01

Medical polymers of biostable nature (e.g. polymethylmetacrylate, PMMA) are widely used in various clinical applications. In this study, novel PMMA-based composite bone cement was prepared. Bioactive glass (BAG) particulate filler (30wt%) was added to enhance potentially the integration of bone to the cement. The polymer matrix was functionalized with trimethoxysilyl to achieve an interfacial bond between the matrix and the fillers of BAG. The amount of trimethoxysilyl in the monomer system varied from 0 to 75wt%. The effects of dry and wet (simulated body fluid, SBF at +37°C for 5 weeks) conditions were investigated. In total, 20 groups of specimens were prepared. The specimens were subjected to a destructive mechanical test in compression. Scanning electron microscopy (SEM) and micro-computed tomography (micro-CT) were used to study the surface and the three-dimensional morphology of the specimens. The results of the study indicated that the addition of trimethoxysilyl groups led to the formation of a hybrid polymer matrix which, in lower amounts (<10wt% of total weight), did not significantly affect the compression properties. However, when the specimens stored in dry and wet conditions were compared, the water sorption increased the compression strength (~5-10MPa per test group). At the same time, the water sorption also caused an evident porous structure formation for the specimens containing BAG and siloxane formation in the hybrid polymer matrix. Copyright © 2015 Elsevier Ltd. All rights reserved.

A multi-scaled hybrid orthopedic implant: bone ECM-shaped Sr-HA nanofibers on the microporous walls of a macroporous titanium scaffold.

PubMed

Han, Yong; Zhou, Jianhong; Zhang, Lan; Xu, Kewei

2011-07-08

We report here, for the first time, a novel multi-scaled hybrid orthopedic implant material consisting of a macroporous Ti scaffold, whose macropores' walls have a microporous titania layer which is fully covered with nanofibers of Sr-doped hydroxyapatite (Sr-HA). The microporous titania layer is formed on and within the Ti scaffold by micro-arc oxidation, which firmly binds to the Ti substrate and contains Ca2+, Sr2+ and PO4(3-) ions. It is then hydrothermally treated to form Sr-HA nanofibers. During the hydrothermal treatment, Sr-HA nanoprisms nucleate from Ca0.5Sr0.5TiO3 pre-formed on the TiO2 and grow in length to nanofibers at the expense of Ca2+, Sr2+ and PO4(3-) ions that migrate from the TiO2. These Sr-HA nanofibers construct a network structure similar to the hierarchical organization of bone extracellular matrix (ECM), and the resulting nanofibrous surface displays a firm adhesion to substrate, superhydrophilicity and apatite-inducing ability. The induced apatite prefers to nucleate on the basal-faceted surfaces of Sr-HA nanofibers. The nanofiber-walled scaffold has a great potential for load-bearing orthotopic use.

A multi-scaled hybrid orthopedic implant: bone ECM-shaped Sr-HA nanofibers on the microporous walls of a macroporous titanium scaffold

NASA Astrophysics Data System (ADS)

Han, Yong; Zhou, Jianhong; Zhang, Lan; Xu, Kewei

2011-07-01

We report here, for the first time, a novel multi-scaled hybrid orthopedic implant material consisting of a macroporous Ti scaffold, whose macropores' walls have a microporous titania layer which is fully covered with nanofibers of Sr-doped hydroxyapatite (Sr-HA). The microporous titania layer is formed on and within the Ti scaffold by micro-arc oxidation, which firmly binds to the Ti substrate and contains Ca2 + , Sr2 + and PO43 - ions. It is then hydrothermally treated to form Sr-HA nanofibers. During the hydrothermal treatment, Sr-HA nanoprisms nucleate from Ca0.5Sr0.5TiO3 pre-formed on the TiO2 and grow in length to nanofibers at the expense of Ca2 + , Sr2 + and PO43 - ions that migrate from the TiO2. These Sr-HA nanofibers construct a network structure similar to the hierarchical organization of bone extracellular matrix (ECM), and the resulting nanofibrous surface displays a firm adhesion to substrate, superhydrophilicity and apatite-inducing ability. The induced apatite prefers to nucleate on the basal-faceted surfaces of Sr-HA nanofibers. The nanofiber-walled scaffold has a great potential for load-bearing orthotopic use.

21 CFR 888.3150 - Elbow joint metal/polymer constrained cemented prosthesis.

Code of Federal Regulations, 2010 CFR

2010-04-01

... use with bone cement (§ 888.3027). (b) Classification. Class II. The special controls for this device...) “Guidance Document for Testing Orthopedic Implants with Modified Metallic Surfaces Apposing Bone or Bone... Biomaterials (Nonporous) for Surgical Implant with Respect to Effect of Material on Muscle and Bone,” (v) F...

21 CFR 888.3150 - Elbow joint metal/polymer constrained cemented prosthesis.

Code of Federal Regulations, 2012 CFR

2012-04-01

... use with bone cement (§ 888.3027). (b) Classification. Class II. The special controls for this device...) “Guidance Document for Testing Orthopedic Implants with Modified Metallic Surfaces Apposing Bone or Bone... Biomaterials (Nonporous) for Surgical Implant with Respect to Effect of Material on Muscle and Bone,” (v) F...

21 CFR 888.3150 - Elbow joint metal/polymer constrained cemented prosthesis.

Code of Federal Regulations, 2014 CFR

2014-04-01

... use with bone cement (§ 888.3027). (b) Classification. Class II. The special controls for this device...) “Guidance Document for Testing Orthopedic Implants with Modified Metallic Surfaces Apposing Bone or Bone... Biomaterials (Nonporous) for Surgical Implant with Respect to Effect of Material on Muscle and Bone,” (v) F...

21 CFR 888.3150 - Elbow joint metal/polymer constrained cemented prosthesis.

Code of Federal Regulations, 2013 CFR

2013-04-01

... use with bone cement (§ 888.3027). (b) Classification. Class II. The special controls for this device...) “Guidance Document for Testing Orthopedic Implants with Modified Metallic Surfaces Apposing Bone or Bone... Biomaterials (Nonporous) for Surgical Implant with Respect to Effect of Material on Muscle and Bone,” (v) F...

21 CFR 888.3150 - Elbow joint metal/polymer constrained cemented prosthesis.

Code of Federal Regulations, 2011 CFR

2011-04-01

... use with bone cement (§ 888.3027). (b) Classification. Class II. The special controls for this device...) “Guidance Document for Testing Orthopedic Implants with Modified Metallic Surfaces Apposing Bone or Bone... Biomaterials (Nonporous) for Surgical Implant with Respect to Effect of Material on Muscle and Bone,” (v) F...

In vivo implant fixation of carbon fiber-reinforced PEEK hip prostheses in an ovine model.

PubMed

Nakahara, Ichiro; Takao, Masaki; Bandoh, Shunichi; Bertollo, Nicky; Walsh, William R; Sugano, Nobuhiko

2013-03-01

Carbon fiber-reinforced polyetheretherketone (CFR/PEEK) is theoretically suitable as a material for use in hip prostheses, offering excellent biocompatibility, mechanical properties, and the absence of metal ions. To evaluate in vivo fixation methods of CFR/PEEK hip prostheses in bone, we examined radiographic and histological results for cementless or cemented CFR/PEEK hip prostheses in an ovine model with implantation up to 52 weeks. CFR/PEEK cups and stems with rough-textured surfaces plus hydroxyapatite (HA) coatings for cementless fixation and CFR/PEEK cups and stems without HA coating for cement fixation were manufactured based on ovine computed tomography (CT) data. Unilateral total hip arthroplasty was performed using cementless or cemented CFR/PEEK hip prostheses. Five cementless cups and stems and six cemented cups and stems were evaluated. On the femoral side, all cementless stems demonstrated bony ongrowth fixation and all cemented stems demonstrated stable fixation without any gaps at both the bone-cement and cement-stem interfaces. All cementless cases and four of the six cemented cases showed minimal stress shielding. On the acetabular side, two of the five cementless cups demonstrated bony ongrowth fixation. Our results suggest that both cementless and cemented CFR/PEEK stems work well for fixation. Cup fixation may be difficult for both cementless and cemented types in this ovine model, but bone ongrowth fixation on the cup was first seen in two cementless cases. Cementless fixation can be achieved using HA-coated CFR/PEEK implants, even under load-bearing conditions. Copyright © 2012 Orthopaedic Research Society.

Evaluation of nanohydroxyapaptite (nano-HA) coated epigallocatechin-3-gallate (EGCG) cross-linked collagen membranes.

PubMed

Chu, Chenyu; Deng, Jia; Man, Yi; Qu, Yili

2017-09-01

Collagen is the main component of extracellular matrix (ECM) with desirable biological activities and low antigenicity. Collagen materials have been widely utilized in guided bone regeneration (GBR) surgery due to its abilities to maintain space for hard tissue growth. However, pure collagen lacks optimal mechanical properties. In our previous study, epigallocatechin-3-gallate (EGCG) cross-linked collagen membranes, with better biological activities and enhanced mechanical properties, may promote osteoblast proliferation, but their effect on osteoblast differentiation is not very significant. Nanohydroxyapatite (nano-HA) is the main component of mineral bone, which possesses exceptional bioactivity properties including good biocompatibility, high osteoconductivity and osteoinductivity, non-immunogenicity and non-inflammatory behavior. Herein, by analyzing the physical and chemical properties as well as the effects on promoting bone regeneration, we have attempted to present a novel EGCG-modified collagen membrane with nano-HA coating, and have found evidence that the novel collagen membrane may promote bone regeneration with a better surface morphology, without destroying collagen backbone. To evaluate the surface morphologies, chemical and mechanical properties of pure collagen membranes, epigallocatechin-3-gallate (EGCG) cross-linked collagen membranes, nano-HA coated collagen membranes, nano-HA coated EGCG-collagen membranes, (ii) to evaluate the bone regeneration promoted by theses membranes. In the present study, collagen membranes were divided into 4 groups: (1) untreated collagen membranes (2) EGCG cross-linked collagen membranes (3) nano-HA modified collagen membranes (4) nano-HA modified EGCG-collagen membranes. Scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FTIR) were used to evaluate surface morphologies and chemical properties, respectively. Mechanical properties were determined by differential scanning calorimeter (DSC

Cement arthroplasty for ankle joint destruction.

PubMed

Lee, Ho-Seong; Ahn, Ji-Yong; Lee, Jong-Seok; Lee, Jun-Young; Jeong, Jae-Jung; Choi, Young Rak

2014-09-03

The aim of this study was to investigate the outcomes of cement arthroplasty used as a primary salvage procedure to treat ankle joint destruction. This study included sixteen patients who underwent primary cement arthroplasty from May 2004 to March 2012 because of an ankle disorder, including intractable infection, nonunion, or a large bone defect or tumor. The mean age of the patients was fifty-seven years (range, twenty-three to seventy-four years), and the mean follow-up period was thirty-nine months (range, fourteen to 100 months). The cement spacer position, cement breakage, osteolysis around the inserted cement, and alignment of the joint were evaluated radiographically. American Orthopaedic Foot & Ankle Society (AOFAS) scores and visual analogue scale (VAS) pain scores were recorded preoperatively and at the time of final follow-up. Functional questionnaires were used to assess the duration for which the patient could walk continuously, use of walking aids, sports activity, consumption of pain medication, and the patient's subjective assessment of the percentage of overall improvement compared with before the cement arthroplasty. The cement spacer was retained without breakage for a mean of thirty-nine months (range, fourteen to 100 months). Osteolysis around the cement was observed in one patient at seventy-eight months, and subluxation developed in one patient. The mean AOFAS and VAS pain scores improved from 39 (range, 11 to 71) preoperatively to 70 (range, 47 to 88) postoperatively (p = 0.001) and from 8 (range, 4 to 9) to 3 (range, 1 to 7) (p = 0.001), respectively. At the final follow-up evaluation, nine of the sixteen patients did not require walking aids, ten used no pain medication, and nine were able to walk continuously for more than an hour. One patient complained of persistent pain and was considered to have had a failure of the procedure. Primary cement arthroplasty might be a treatment option for advanced ankle destruction in elderly and less

Strontium enhances osseointegration of calcium phosphate cement: a histomorphometric pilot study in ovariectomized rats.

PubMed

Baier, Martin; Staudt, Patric; Klein, Roman; Sommer, Ulrike; Wenz, Robert; Grafe, Ingo; Meeder, Peter Jürgen; Nawroth, Peter P; Kasperk, Christian

2013-06-07

Calcium phosphate cements are used frequently in orthopedic and dental surgeries. Strontium-containing drugs serve as systemic osteoblast-activating medication in various clinical settings promoting mechanical stability of the osteoporotic bone. Strontium-containing calcium phosphate cement (SPC) and calcium phosphate cement (CPC) were compared regarding their local and systemic effects on bone tissue in a standard animal model for osteoporotic bone. A bone defect was created in the distal femoral metaphysis of 60 ovariectomized Sprague-Dawley rats. CPC and SPC were used to fill the defects in 30 rats in each group. Local effects were assessed by histomorphometry at the implant site. Systemic effects were assessed by bone mineral density (BMD) measurements at the contralateral femur and the spine. Faster osseointegration and more new bone formation were found for SPC as compared to CPC implant sites. SPC implants exhibited more cracks than CPC implants, allowing more bone formation within the implant. Contralateral femur BMD and spine BMD did not differ significantly between the groups. The addition of strontium to calcium phosphate stimulates bone formation in and around the implant. Systemic release of strontium from the SPC implants did not lead to sufficiently high serum strontium levels to induce significant systemic effects on bone mass in this rat model.

Effect of the up-front heat treatment of gelatin particles dispersed in calcium phosphate cements on the in vivo material resorption and concomitant bone formation.

PubMed

Yamamoto, Shoko; Matsushima, Yuta; Kanayama, Yoshitaka; Seki, Azusa; Honda, Haruya; Unuma, Hidero; Sakai, Yasuo

2017-03-01

Calcium phosphate cements (CPCs), consisting of a mixture of calcium phosphate powders and setting liquid, have been widely used in orthopedic applications. One of the drawbacks of CPCs is their poor resorbability in the living body, which hinders substitution with natural bones. One of the strategies to facilitate the resorption of CPCs is the incorporation of bioresorbable or water-soluble pore-generating particles (porogens), such as gelatin, in the CPC matrices. In spite of numerous reports, however, little is known about the effect of the dissolution/resorption rate of the porogens on concomitant bone regeneration. In the present study, we prepared preset CPCs dispersed with 10 mass% of low-endotoxin gelatin particles 200-500 μm in diameter having different heat-treatment histories, therefore exhibiting different dissolution rate, and then the obtained CPC/gelatin composites were evaluated for in vivo resorption and concomitant in vivo bone formation behaviors. As the results, the dispersion of gelatin particles markedly promoted in vivo resorption of CPC, and enhanced concomitant bone formation, connective tissue formation, osteoblast proliferation, and vascularization. The dissolution/resorption rate was able to be controlled by changing the up-front heat-treatment temperature. In particular, when CPC/gelatin composites were implanted in distal metaphysis of rabbits, the optimum dissolution/resorption was attained by heat-treating gelatin particles at 383 K for 24 h before dispersing in CPC. Quick resorption of calcium phosphate cement and concomitant bone formation by dispersing properly heat-treated with gelatin particles.

Characteristics of Bone Tissue and Composite Materials on the Basis of Natural Hydroxyapatite and Endodontic Cement for Replacement of the Tissue

NASA Astrophysics Data System (ADS)

Filipenkov, V. V.; Rupeks, L. E.; Vitins, V. M.; Knets, I. V.; Kasyanov, V. A.

2017-07-01

New biocomposites and the cattle bone tissue were investigated. The composites were made from an endodontic cement (EC) and natural hydroxyapatite (NHAp.) The results of experiments performed by the method of infrared spectroscopy showed that protein was removed from the heat-treated specimens of bone tissue practically completely. The structure of bone tissue before and after deproteinization and the structure of the composite materials based on NHAp and EC (with different percentage) were investigated by the method of optical microscopy. The characteristics of mechanical properties (the initial elastic modulus, breaking tensile and compressive stresses, and breaking strain) and the density and porosity of these materials were determined. The new composite materials were implanted in the live tissue of rat. Biocompatibility between the live tissue and the new biocomposites was estimated.

Basic properties of calcium phosphate cement containing atelocollagen in its liquid or powder phases.

PubMed

Miyamoto, Y; Ishikawa, K; Takechi, M; Toh, T; Yuasa, T; Nagayama, M; Suzuki, K

1998-01-01

The basic properties of calcium phosphate cement (CPC) containing atelocollagen, the main component of the organic substrate in bone, were studied in an initial evaluation for the fabrication of modified CPC. The setting time of conventional CPC (c-CPC) was prolonged to over 100 min when c-CPC contained 1% or more atelocollagen. The diametral tensile strength (DTS) of c-CPC decreased linearly with the collagen content, descending to below the detection limit when the c-CPC contained 3% or more atelocollagen. Therefore, use of c-CPC as the base cement seems inappropriate for the fabrication of atelocollagen-containing CPC. In contrast, the cement set at 9-34 min when fast-setting CPC (FSCPC) was used as the base cement and contained 1-5% atelocollagen, respectively. Although addition of atelocollagen resulted in the decrease of DTS of the set mass, the DTS was approximately the same, 6-8 MPa, at contents of atelocollagen between 1% and 5%. When atelocollagen was added to FSCPC, the handling property was improved significantly. The paste also became more adhesive with increase in atelocollagen content. These properties are desirable for its use in surgical procedures since, for example, bony defects can be filled easily and without a space interposed between the bone and cement paste. Although there are some disadvantages for the addition of atelocollagen to CPC, it can be accepted as long as FSCPC was used as the base cement. We conclude that further evaluations of the effects of atelocollagen, such as biocompatibility, bone synthesis, and bone replacement behaviour should be done, using FSCPC as the base cement.

Positive effect of removal of subchondral bone plate for cemented acetabular component fixation in total hip arthroplasty: a randomised RSA study with ten-year follow-up.

PubMed

Flivik, G; Kristiansson, I; Ryd, L

2015-01-01

We hypothesised that the removal of the subchondral bone plate (SCBP) for cemented acetabular component fixation in total hip arthroplasty (THA) offers advantages over retention by improving the cement-bone interface, without jeopardising implant stability. We have previously published two-year follow-up data of a randomised controlled trial (RCT), in which 50 patients with primary osteoarthritis were randomised to either retention or removal of the SCBP. The mean age of the retention group (n = 25, 13 males) was 70.0 years (sd 6.8). The mean age in the removal group (n = 25, 16 males) was 70.3 years (sd 7.9). Now we have followed up the patients at six (retention group, n = 21; removal group, n = 20) and ten years (retention group: n = 17, removal group: n = 18), administering clinical outcome questionnaires and radiostereometric analysis (RSA), and determining the presence of radiolucent lines (RLLs) on conventional radiographs. RSA demonstrated similar translation and rotation patterns up to six years. Between six and ten years, proximal acetabular component migration and changes of inclination were larger in the retention group, although the mean differences did not reach statistical significance. Differences in migration were driven by two patients in the SCBP retention group with extensive migration versus none in the SCBP removal group. The significant difference (p < 0.001) in the development of radiolucent lines in the retention group, previously observed at two years, increased even further during the course of follow-up (p < 0.001). While recognising SCBP removal is a more demanding technique, we conclude that, wherever possible, the SCBP should be removed to improve the cement-bone interface in order to maximise acetabular component stability and longevity. ©2015 The British Editorial Society of Bone & Joint Surgery.

Microbial resistance related to antibiotic-loaded bone cement: a historical review.

PubMed

Walker, Lucy C; Baker, Paul; Holleyman, Richard; Deehan, David

2017-12-01

The use of antibiotic-loaded bone cement (ALBC) has a range of indications for use in orthopaedics. It has the advantage of delivering high loads of antibiotics to a targeted site, thereby avoiding the side effects associated with systemic administration. However, there is concern that the use of ALBC may precipitate the development of antibiotic-resistant bacteria. This review focuses on (1) the published research using both animal and human models examining the association between ALBC and the induction of microbial resistance (2) the mechanisms by which antimicrobial resistance develop (3) the research pertaining to specific classes of antibiotics commonly used in orthopaedic practice (4) the recent developments in calcium sulphate beads, nanoparticles and chitosan, as alternative antimicrobial treatments for periprosthetic joint infections. The literature for and against a link between ALBC and the development of microbiological resistance is reviewed and presented. It is concluded that further research is needed to develop a defined set of indications for the use of ALBC in the management of periprosthetic joint infection. In addition, further research into alternative antimicrobial therapies in this area should be encouraged.

Contrasting Effects of Physical Wear on Elution of Two Antibiotics from Orthopedic Cement

PubMed Central

Dodds, S.; Akid, R.; Stephenson, J.; Nichol, T.; Banerjee, R. D.; Stockley, I.; Townsend, R.

2012-01-01

The use of antibiotics as a supplement to bone cement for the purposes of providing a local release of antibiotics is common practice in arthroplasty surgery and the kinetics of elution of the antibiotics in such systems have been investigated previously. However, in these previous studies no account was taken of the potential effects that wear may have on the elution kinetics of the antibiotic. Here, we have modified an existing wear testing rig to allow the simultaneous study of the elution kinetics of bone cement samples containing antibiotics being subjected to immersion only and immersion and conjoint wear. The results show contrasting effects with two commonly used antibiotics. Bone cement containing daptomycin showed no substantial change in antibiotic elution due to wear, while cement containing gentamicin (the most commonly used antibiotic in this application) in contrast demonstrated a substantial reduction in the rate of antibiotic elution when wear was applied. Scanning electron microscopy revealed a possible explanation for these diverse results, due to wear-induced “sealing” of the surface in conjunction with the crystal morphology of the antibiotic. PMID:22155831

Knee stabilisation following infected knee arthroplasty with bone loss and extensor mechanism impairment using a modular cemented nail.

PubMed

Rao, M C; Richards, O; Meyer, C; Jones, R Spencer

2009-12-01

Infected Total Knee Replacement with significant bone loss and loss of extensor mechanism poses a difficult management problem. Arthrodesis relying on bony union can be difficult to achieve and can result in significant limb shortening. We retrospectively looked at the outcome of seven patients with significant bone loss and extensor mechanism insufficiency following infected TKR who underwent knee stabilisation using a modular cemented nail. The nail relied on the strong coupling mechanism between the modular femoral and tibial components. Pain score improved from a mean of 7.9 pre-operatively to 1.5 post-operatively at a mean follow up of 39.6 months (range 7-68) months. Two patients underwent technically easy revision nailing for recurrent infection and aseptic loosening. The Endo-Model(R) Knee Fusion Nail (Newsplint, UK/Waldemar Link, GmbH & Co. KG, Hamburg, Germany) has good early results in terms of pain relief and provides a stable knee in cases with significant bone loss and extensor mechanism insufficiency following an infected TKR thus avoiding an above knee amputation.

Pedicle screw cement augmentation. A mechanical pullout study on different cement augmentation techniques.

PubMed

Costa, Francesco; Ortolina, Alessandro; Galbusera, Fabio; Cardia, Andrea; Sala, Giuseppe; Ronchi, Franco; Uccelli, Carlo; Grosso, Rossella; Fornari, Maurizio

2016-02-01

Pedicle screws with polymethyl methacrylate (PMMA) cement augmentation have been shown to significantly improve the fixation strength in a severely osteoporotic spine. However, the efficacy of screw fixation for different cement augmentation techniques remains unknown. This study aimed to determine the difference in pullout strength between different cement augmentation techniques. Uniform synthetic bones simulating severe osteoporosis were used to provide a platform for each augmentation technique. In all cases a polyaxial screw and acrylic cement (PMMA) at medium viscosity were used. Five groups were analyzed: I) only screw without PMMA (control group); II) retrograde cement pre-filling of the tapped area; III) cannulated and fenestrate screw with cement injection through perforation; IV) injection using a standard trocar of PMMA (vertebroplasty) and retrograde pre-filling of the tapped area; V) injection through a fenestrated trocar and retrograde pre-filling of the tapped area. Standard X-rays were taken in order to visualize cement distribution in each group. Pedicle screws at full insertion were then tested for axial pullout failure using a mechanical testing machine. A total of 30 screws were tested. The results of pullout analysis revealed better results of all groups with respect to the control group. In particular the statistical analysis showed a difference of Group V (p = 0.001) with respect to all other groups. These results confirm that the cement augmentation grants better results in pullout axial forces. Moreover they suggest better load resistance to axial forces when the distribution of the PMMA is along all the screw combining fenestration and pre-filling augmentation technique. Copyright © 2015 IPEM. Published by Elsevier Ltd. All rights reserved.

A critical assessment of proximal macrotexturing on cemented femoral components.

PubMed

Duffy, G P; Muratoglu, O K; Biggs, S A; Larson, S L; Lozynsky, A J; Harris, W H

2001-12-01

We analyzed the cement-metal interface of 3 different types of femoral components that had proximal macrotexturing after in vitro insertion and after fatigue testing designed to produce debonding and micromotion. These components were compared with clinical retrieval specimens. The cement did not flow into the macrotexturing; rather, hollow, brittle volcanoes or calderas were formed. These fragile protrusions of cement become worn down or abraded by debonded components. This abrasion of cement may contribute to the early and aggressive osteolysis seen in some of these early failures with proximal macrotextured components. The formation of these volcanos and calderas can be aborted by placing bone-cement onto the macrotexturing before stem insertion. This simple technique allows the macrotexturing to be filled with cement.

Engineering a biomimetic three-dimensional nanostructured bone model for breast cancer bone metastasis study.

PubMed

Zhu, Wei; Wang, Mian; Fu, Yebo; Castro, Nathan J; Fu, Sidney W; Zhang, Lijie Grace

2015-03-01

Traditional breast cancer (BrCa) bone metastasis models contain many limitations with regards to controllability, reproducibility and flexibility of design. In this study, a novel biomimetic bone microenvironment was created by integrating hydroxyapatite (HA) and native bioactive factors deposited by osteogenic induction of human bone marrow mesenchymal stem cells (MSCs) within a cytocompatible chitosan hydrogel. It was found that a 10% nanocrystalline HA (nHA) chitosan scaffold exhibited the highest BrCa adhesion and proliferation when compared to chitosan scaffolds with 20% nHA, 10% and 20% microcrystalline HA as well as amorphous HA. This 3-D tunable bone scaffold can provide a biologically relevant environment, increase cell-cell and cell-matrix interactions as found in native bone, and retain the behavior of BrCa cells with different metastasis potential (i.e. highly metastatic MDA-MB-231, less metastatic MCF-7 and transfected MDA-MB-231). The co-culture of MSCs and MDA-MB-231 in this bone model illustrated that MSCs have the capacity to upregulate the expression of the well-known metastasis-associated gene metadherin within BrCa cells. In summary, this study illustrates the ability of our 3-D bone model to create a biomimetic environment conducive to recapitulating the behavior of metastatic BrCa cells, making it a promising tool for in vitro BrCa cell bone metastasis study and for the discovery of potential therapeutics. Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Percutaneous vertebroplasty and bone cement leakage: clinical experience with a new high-viscosity bone cement and delivery system for vertebral augmentation in benign and malignant compression fractures.

PubMed

Anselmetti, Giovanni Carlo; Zoarski, Gregg; Manca, Antonio; Masala, Salvatore; Eminefendic, Haris; Russo, Filippo; Regge, Daniele

2008-01-01

The aim of this study was to assess the feasibility of and venous leakage reduction in percutaneous vertebroplasty (PV) using a new high-viscosity bone cement (PMMA). PV has been used effectively for pain relief in osteoporotic and malignant vertebral fractures. Cement extrusion is a common problem and can lead to complications. Sixty patients (52 female; mean age, 72.2 +/- 7.2) suffering from osteoporosis (46), malignancy (12), and angiomas (2), divided into two groups (A and B), underwent PV on 190 vertebrae (86 dorsal, 104 lumbar). In Group A, PV with high-viscosity PMMA (Confidence, Disc-O-Tech, Israel) was used. This PMMA was injected by a proprietary delivery system, a hydraulic saline-filled screw injector. In Group B, a standard low-viscosity PMMA was used. Postprocedural CT was carried out to detect PMMA leakages and complications. Fisher's exact test and Wilcoxon rank test were used to assess significant differences (p < 0.05) in leakages and to evaluate the clinical outcome. PV was feasible, achieving good clinical outcome (p < 0.0001) without major complications. In Group A, postprocedural CT showed an asymptomatic leak in the venous structures of 8 of 98 (8.2%) treated vertebrae; a discoidal leak occurred in 6 of 98 (6.1%). In Group B, a venous leak was seen in 38 of 92 (41.3%) and a discoidal leak in 12 of 92 (13.0%). Reduction of venous leak obtained by high-viscosity PMMA was highly significant (p < 0.0001), whereas this result was not significant (p = 0.14) related to the disc. The high-viscosity PMMA system is safe and effective for clinical use, allowing a significant reduction of extravasation rate and, thus, leakage-related complications.

Percutaneous Vertebroplasty and Bone Cement Leakage: Clinical Experience with a New High-Viscosity Bone Cement and Delivery System for Vertebral Augmentation in Benign and Malignant Compression Fractures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anselmetti, Giovanni Carlo, E-mail: giovanni.anselmetti@ircc.i; Zoarski, Gregg; Manca, Antonio

The aim of this study was to assess the feasibility of and venous leakage reduction in percutaneous vertebroplasty (PV) using a new high-viscosity bone cement (PMMA). PV has been used effectively for pain relief in osteoporotic and malignant vertebral fractures. Cement extrusion is a common problem and can lead to complications. Sixty patients (52 female; mean age, 72.2 {+-} 7.2) suffering from osteoporosis (46), malignancy (12), and angiomas (2), divided into two groups (A and B), underwent PV on 190 vertebrae (86 dorsal, 104 lumbar). In Group A, PV with high-viscosity PMMA (Confidence, Disc-O-Tech, Israel) was used. This PMMA wasmore » injected by a proprietary delivery system, a hydraulic saline-filled screw injector. In Group B, a standard low-viscosity PMMA was used. Postprocedural CT was carried out to detect PMMA leakages and complications. Fisher's exact test and Wilcoxon rank test were used to assess significant differences (p < 0.05) in leakages and to evaluate the clinical outcome. PV was feasible, achieving good clinical outcome (p < 0.0001) without major complications. In Group A, postprocedural CT showed an asymptomatic leak in the venous structures of 8 of 98 (8.2%) treated vertebrae; a discoidal leak occurred in 6 of 98 (6.1%). In Group B, a venous leak was seen in 38 of 92 (41.3%) and a discoidal leak in 12 of 92 (13.0%). Reduction of venous leak obtained by high-viscosity PMMA was highly significant (p < 0.0001), whereas this result was not significant (p = 0.14) related to the disc. The high-viscosity PMMA system is safe and effective for clinical use, allowing a significant reduction of extravasation rate and, thus, leakage-related complications.« less

The effect of void creation prior to vertebroplasty on intravertebral pressure and cement distribution in cadaveric spines with simulated metastases.

PubMed

Li, Ka; Yan, Jun; Yang, Qiang; Li, Zhenfeng; Li, Jianmin

2015-01-28

For osteoporosis or spinal metastases, percutaneous vertebroplasty is effective in pain relief and improvement of mobility. However, the complication rate (cement extravasation and fat embolisms) is relatively higher in the treatment of spinal metastases. The presence of tumor tissue plays a significant role in intravertebral pressure and cement distribution and thereby affects the occurrence of complications. We investigated the effect of void creation prior to vertebroplasty on intravertebral pressure and cement distribution in spinal metastases. Eighteen vertebrae (T8-L4) from five cadaveric spines were randomly allocated for two groups (group with and without void) of nine vertebrae each. Defect was created by removing a central core of cancellous bone in the vertebral body and then filling it with 30% or 100% fresh muscle paste by volume to simulate void creation or no void creation, respectively. Then, 20% bone cement by volume of the vertebral body was injected into each specimen through a unipedicular approach at a rate of 3 mL/min. The gender of the donor, vertebral body size, bone density, cement volume, and intravertebral pressure were recorded. Then, computed tomography scans and cross sections were taken to evaluate the cement distribution in vertebral bodies. No significant difference was found between the two groups in terms of the gender of the donor, vertebral body size, bone density, or bone cement volume. The average maximum intravertebral pressure in the group with void creation was significantly lower than that in the group without void creation (1.20 versus 5.09 kPa, P = 0.001). Especially during the filling of void, the difference was more pronounced. Void creation prior to vertebroplasty allowed the bone cement to infiltrate into the lytic defect. In vertebroplasty for spinal metastases, void creation produced lower intravertebral pressure and facilitated cement filling. To reduce the occurrence of complication, it may be an alternative

Pre-clinical evaluation of the mechanical properties of a low-stiffness cement-injectable hip stem.

PubMed

Eldesouky, Ibrahim; Harrysson, Ola; Marcellin-Little, Denis J; West, Harvey; El-Hofy, Hassan

2017-11-01

In total hip arthroplasty (THA), the femoral stem can be fixed with or without bone cement. Cementless stem fixation is recommended for young and active patients as it eliminates the risk of loss of fixation at the bone-cement and cement-implant interfaces. Cementless fixation, however, suffers from a relatively high early revision rate. In the current research, a novel low-stiffness hip stem was designed, fabricated and tested. The stem design provided the option to inject biodegradable bone cement that could enhance initial stem stability. The stem was made of Ti6Al4V alloy. The proximal portion of the stem was porous, with cubic cells. The stem was fabricated using electron beam melting (EBM) technology and tested in compression and bending. Finite-element analysis was used to evaluate stem performance under a dynamic load representing a stair descending cycle and compare it to the performance of a solid stem with similar geometry. The von Mises stresses and maximum principal strains generated within the bone increased after porous stem insertion compared to solid stem insertion. The low-modulus stem tested in this study has acceptable mechanical properties and generates strain patterns in bone that appear compatible with clinical use.

Efficacy of the biomaterials 3wt%-nanostrontium-hydroxyapatite-enhanced calcium phosphate cement (nanoSr-CPC) and nanoSr-CPC-incorporated simvastatin-loaded poly(lactic-co-glycolic-acid) microspheres in osteogenesis improvement: An explorative multi-phase experimental in vitro/vivo study.

PubMed

Masaeli, Reza; Jafarzadeh Kashi, Tahereh Sadat; Dinarvand, Rassoul; Rakhshan, Vahid; Shahoon, Hossein; Hooshmand, Behzad; Mashhadi Abbas, Fatemeh; Raz, Majid; Rajabnejad, Alireza; Eslami, Hossein; Khoshroo, Kimia; Tahriri, Mohammadreza; Tayebi, Lobat

2016-12-01

The purpose of this multi-phase explorative in vivo animal/surgical and in vitro multi-test experimental study was to (1) create a 3wt%-nanostrontium hydroxyapatite-enhanced calcium phosphate cement (Sr-HA/CPC) for increasing bone formation and (2) creating a simvastatin-loaded poly(lactic-co-glycolic acid) (SIM-loaded PLGA) microspheres plus CPC composite (SIM-loaded PLGA+nanostrontium-CPC). The third goal was the extensive assessment of multiple in vitro and in vivo characteristics of the above experimental explorative products in vitro and in vivo (animal and surgical studies). Physical and chemical properties of the prepared Sr-HA/CPC were evaluated. MTT assay and alkaline phosphatase activities, and radiological and histological examinations of Sr-HA/CPC, CPC and negative control were compared. X-ray diffraction (XRD) indicated that crystallinity of the prepared cement increased by increasing the powder-to-liquid ratio. Incorporation of Sr-HA into CPC increased MTT assay (biocompatibility) and ALP activity (P<0.05). Histomorphometry showed greater bone formation after 4weeks, after implantation of Sr-HA/CPC in 10 rats compared to implantations of CPC or empty defects in the same rats (n=30, ANOVA P<0.05). METHODS AND RESULTS PERTAINING TO SIM-LOADED PLGA MICROSPHERES+NANOSTRONTIUM-CPC COMPOSITE: After SEM assessment, the produced composite of microspheres and enhanced CPC were implanted for 8weeks in 10 rabbits, along with positive and negative controls, enhanced CPC, and enhanced CPC plus SIM (n=50). In the control group, only a small amount of bone had been regenerated (localized at the boundary of the defect); whereas, other groups showed new bone formation within and around the materials. A significant difference was found in the osteogenesis induced by the groups sham control (16.96±1.01), bone materials (32.28±4.03), nanostrontium-CPC (24.84±2.6), nanostrontium-CPC-simvastatin (40.12±3.29), and SIM-loaded PLGA+nanostrontium-CPC (44.8±6.45) (ANOVA P

Development of multi-walled carbon nanotubes reinforced monetite bionanocomposite cements for orthopedic applications.

PubMed

Boroujeni, Nariman Mansoori; Zhou, Huan; Luchini, Timothy J F; Bhaduri, Sarit B

2013-10-01

In this study, we present results of our research on biodegradable monetite (DCPA, CaHPO4) cement with surface-modified multi-walled carbon nanotubes (mMWCNTs) as potential bone defect repair material. The cement pastes showed desirable handling properties and possessed a suitable setting time for use in surgical setting. The incorporation of mMWCNTs shortened the setting time of DCPA and increased the compressive strength of DCPA cement from 11.09±1.85 MPa to 21.56±2.47 MPa. The cytocompatibility of the materials was investigated in vitro using the preosteoblast cell line MC3T3-E1. An increase of cell numbers was observed on both DCPA and DCPA-mMWCNTs. Scanning electron microscopy (SEM) results also revealed an obvious cell growth on the surface of the cements. Based on these results, DCPA-mMWCNTs composite cements can be considered as potential bone defect repair materials. © 2013.

Reinforcing of a calcium phosphate cement with hydroxyapatite crystals of various morphologies.

PubMed

Neira, Inés S; Kolen'ko, Yury V; Kommareddy, Krishna P; Manjubala, Inderchand; Yoshimura, Masahiro; Guitián, Francisco

2010-11-01

A series of biocomposite materials was successfully prepared by reinforcing advanced calcium phosphate cement with hydroxyapatite fibrous and elongated plate-like particles. Powder X-ray diffraction showed that ball-milled biocomposite precursors (dicalcium and tetracalcium phosphates) entirely transform to a single phase hydroxyapatite end product within 7 h at 37 °C. Electron microscopy showed that the resultant biocomposites are constituted of nanoscaled cement particles intimately associated with the reinforcement crystals. The influence of shape, size, and concentration of the hydroxyapatite filler on the compression strength of reinforced cements is discussed. The best compression strength of 37 ± 3 MPa (enhancement of ∼50% compared to pure cement) was achieved using submicrometer-sized hydroxyapatite crystals with complementary shapes. Nanoindentation revealed that averaged elastic modulus and hardness values of the cements are consistent with those reported for trabecular and cortical human bones, indicating a good match of the micromechanical properties for their potential use for bone repair. The stiffness of the biocomposites was confirmed to gradate-compliant cement matrix, cement-filler interface, and stiff filler-as a result of the structuring at the nanometer-micrometer level. This architecture is critical in conditioning the final mechanical properties of the functional composite biomaterial. In vitro cell culture experiments showed that the developed biomaterial system is noncytotoxic.

Evaluating Device Design and Cleanability of Orthopedic Device Models Contaminated with a Clinically Relevant Bone Test Soil.

PubMed

Lucas, Anne D; Nagaraja, Srinidhi; Gordon, Edward A; Hitchins, Victoria M

2015-01-01

Reusable medical devices need to be cleaned prior to disinfection or sterilization and subsequent use to prevent infections. The cleanability of medical devices depends in part on the design of the device. This study examined how models of orthopedic medical devices of increasing complexity retain calcium phosphate bone cement, a relevant test soil for these devices. The dye Alizarin Red S and micro-computed tomography (μCT) were used to assess the amount and location of bone cement debris in a series of model orthopedic devices. Testing was performed after soiling and cleaning once, and soiling and cleaning 10 times. The color change of the dye after reacting with the bone cement was useful for indicating the presence of bone cement in these models. High-resolution μCT analysis provided the volume and location of the bone cement. Models that were more complex retained significantly more bone debris than simpler designs. Model devices repeatedly soiled and cleaned 10 times retained significantly more bone debris than those soiled and cleaned once. Significantly more bone cement was retained in the more complex lumen structures. This information may be useful in designing reusable orthopedic devices, and other complex medical devices with lumens.

Mimix hydroxyapatite cement use in the reconstruction of the craniofacial skeleton.

PubMed

Mann, Robert J; Blount, Andrew L; Neaman, Keith C; Korepta, Lindsey

2011-11-01

Reconstruction of the craniofacial skeleton has undergone a significant evolution during the past century. Initially, the use of autogenous bone grafts from various sites was the criterion standard. However, owing to donor site morbidity and lack of sufficient bone for large defects, surgeons have relied on various bone substitutes. Hydroxyapatite (HA) has served as an alternative to autogenous grafts, but questions regarding biocompatibility, risk of infection, and slow set times have hampered its acceptance. This article serves as a review of a single surgeon's experience using HA in the craniofacial skeleton. Eighteen patients receiving HA between March 2000 and November 2006 were observed. Sixteen underwent recontouring of skull-based bone defects, and 2 underwent recontouring for nasal and alveolar defects. The mean amount of HA used in each patient was 30.2 g. For large contour irregularities, the maximum thickness of HA used was 8 mm. The size of bone defects ameliorated averaged 4.8 cm(2). Complications occurred in 3 (16.7%) of 18 patients and included scalp hematoma and superficial cellulitis. In addition, 1 patient developed a facial abscess after placement along the alveolar floor, which necessitated removal. Hydroxyapatite represents a viable alternative to autogenous bone grafts when used in the correct manner. Hydroxyapatite should be used only for smaller defects or used in conjunction with absorbable plates when attempting to fill larger defects. Use of HA for nasal piriform augmentation or alveolar bone grafting should not be considered owing to problems with late infections.

Bone ingrowth in bFGF-coated hydroxyapatite ceramic implants.

PubMed

Schnettler, Reinhard; Alt, Volker; Dingeldein, Elvira; Pfefferle, Hans-Joachim; Kilian, Olaf; Meyer, Christof; Heiss, Christian; Wenisch, Sabine

2003-11-01

This experimental study was performed to evaluate angiogenesis, bone formation, and bone ingrowth in response to osteoinductive implants of bovine-derived hydroxyapatite (HA) ceramics either uncoated or coated with basic fibroblast growth factor (bFGF) in miniature pigs. A cylindrical bone defect was created in both femur condyles of 24 miniature pigs using a saline coated trephine. Sixteen of the 48 defects were filled with HA cylinders coated with 50 microg rhbFG, uncoated HA cylinders, and with autogenous transplants, respectively. Fluorochrome labelled histological analysis, histomorphometry, and scanning electron microscopy were performed to study angiogenesis, bone formation and bone ingrowth. Complete bone ingrowth into bFGF-coated HA implants and autografts was seen after 34 days compared to 80 days in the uncoated HA group. Active ring-shaped areas of fluorochrome labelled bone deposition with dynamic bone remodelling were found in all cylinders. New vessels could be found in all cylinders. Histomorphometric analysis showed no difference in bone ingrowth over time between autogenous transplants and bFGF-coated HA implants. The current experimental study revealed comparable results of bFGF-coated HA implants and autogenous grafts regarding angiogenesis, bone synthesis and bone ingrowth.

Bone Regeneration of Hydroxyapatite with Granular Form or Porous Scaffold in Canine Alveolar Sockets

PubMed Central

JANG, SEOK JIN; KIM, SE EUN; HAN, TAE SUNG; SON, JUN SIK; KANG, SEONG SOO; CHOI, SEOK HWA

2017-01-01

This study was undertaken to assess bone regeneration using hydroxyapatite (HA). The primary focus was comparison of bone regeneration between granular HA (gHA) forms and porous HA (pHA) scaffold. The extracted canine alveolar sockets were divided with three groups: control, gHA and pHA. Osteogenic effect in the gHA and pHA groups showed bone-specific surface and bone mineral density to be significantly higher than that of the control group (p<0.01). Bone volume fraction, bone mineral density, and amount of connective tissue related to disturbing osseointegration of the gHA group was higher than in the pHA group. Quantity of new bone formation of the pHA group was higher than that of the gHA group. This study demonstrated that gHA and pHA are potentially good bone substitutes for alveolar socket healing. For new bone formation during 8 weeks' post-implantation, HA with porous scaffold was superior to the granular form of HA. PMID:28438860

Contrast Agents for Micro-Computed Tomography of Microdamage in Bone

DTIC Science & Technology

2011-01-01

solution from DI water (or PBS). For the second model, a 5 mm cube of cortical bone tissue was embedded in polymethylmethacrylate and sectioned...radiography1 and as a radiopacifer in polymethylmethacrylate bone cement.2 Current commercial products for either application use microscale BaSO4 particles... polymethylmethacrylate bone cement (Lewis, 1997). The objective of this study was to non-destructively and three-dimensionally image microdamage

Porous polymethylmethacrylate as bone substitute in the craniofacial area.

PubMed

Bruens, Marco L; Pieterman, Herman; de Wijn, Joost R; Vaandrager, J Michael

2003-01-01

In craniofacial surgery, alloplastic materials are used for correcting bony defects. Porous polymethylmethacrylate (PMMA) is a biocompatible and nondegradable bone cement. Porous PMMA is formed by the classic bone cement formulation of methylmethacrylate liquid and PMMA powder in which an aqueous biodegradable carboxymethylcellulose gel is dispersed to create pores in the cement when cured. Pores give bone the opportunity to grow in, resulting in a better fixation of the prostheses. We evaluated the long-term results (n = 14), up to 20 years, of augmentations and defect fillings in the craniofacial area, with special interest in possible side effects and bone ingrowth. The evaluation consisted of a questionnaire, a physical examination, and a computed tomography (CT) scan. There were no side effects that could be ascribed to the porous PMMA. Twelve CT scans showed bone ingrowth into the prostheses, proving the validity behind the concept of porous PMMA.

Influence of cement compressive strength and porosity on augmentation performance in a model of orthopedic screw pull-out.

PubMed

Pujari-Palmer, Michael; Robo, Celine; Persson, Cecilia; Procter, Philip; Engqvist, Håkan

2018-01-01

Disease and injuries that affect the skeletal system may require surgical intervention and internal fixation, i.e. orthopedic plate and screw insertion, to stabilize the injury and facilitate tissue repair. If the surrounding bone quality is poor the screws may migrate, or the bone may fail, resulting in fixation failure. While numerous studies have shown that cement augmentation of the interface between bone and implant can increase screw pull-out force, the physical properties of cement that influence pull-out force have not been investigated. The present study sought to determine how the physical properties of high strength calcium phosphate cements (hsCPCs, specifically dicalcium phosphate) affected the corresponding orthopedic screw pull-out force in urethane foam models of "healthy" and "osteoporotic" synthetic bone (Sawbones). In the simplest model, where only the bond strength between screw thread and cement (without Sawbone) was tested, the correlation between pull-out force and cement compressive strength (R 2 = 0.79) was weaker than correlation with total cement porosity (R 2 = 0.89). In open pore Sawbone that mimics "healthy" cancellous bone density the stronger cements produced higher pull-out force (50-60% increase). High strength, low porosity cements also produced higher pull-out forces (50-190% increase) in "healthy" Sawbones with cortical fixation if the failure strength of the cortical material was similar to, or greater than (a metal shell), actual cortical bone. This result is of particular clinical relevance where fixation with a metal plate implant is indicated, as the nearby metal can simulate a thicker cortical shell, thereby increasing the pull-out force of screws augmented with stronger cements. The improvement in pull-out force was apparent even at low augmentation volumes of 0.5mL (50% increase), which suggest that in clinical situations where augmentation volume is limited the stronger, lower porosity calcium phosphate cement (CPC) may

Evaluation of injectable strontium-containing borate bioactive glass cement with enhanced osteogenic capacity in a critical-sized rabbit femoral condyle defect model.

PubMed

Zhang, Yadong; Cui, Xu; Zhao, Shichang; Wang, Hui; Rahaman, Mohamed N; Liu, Zhongtang; Huang, Wenhai; Zhang, Changqing

2015-02-04

The development of a new generation of injectable bone cements that are bioactive and have enhanced osteogenic capacity for rapid osseointegration is receiving considerable interest. In this study, a novel injectable cement (designated Sr-BBG) composed of strontium-doped borate bioactive glass particles and a chitosan-based bonding phase was prepared and evaluated in vitro and in vivo. The bioactive glass provided the benefits of bioactivity, conversion to hydroxyapatite, and the ability to stimulate osteogenesis, while the chitosan provided a cohesive biocompatible and biodegradable bonding phase. The Sr-BBG cement showed the ability to set in situ (initial setting time = 11.6 ± 1.2 min) and a compressive strength of 19 ± 1 MPa. The Sr-BBG cement enhanced the proliferation and osteogenic differentiation of human bone marrow-derived mesenchymal stem cells in vitro when compared to a similar cement (BBG) composed of chitosan-bonded borate bioactive glass particles without Sr. Microcomputed tomography and histology of critical-sized rabbit femoral condyle defects implanted with the cements showed the osteogenic capacity of the Sr-BBG cement. New bone was observed at different distances from the Sr-BBG implants within eight weeks. The bone-implant contact index was significantly higher for the Sr-BBG implant than it was for the BBG implant. Together, the results indicate that this Sr-BBG cement is a promising implant for healing irregularly shaped bone defects using minimally invasive surgery.

The importance of pulsed lavage on interface temperature and ligament tension force in cemented unicompartmental knee arthroplasty.

PubMed

Clarius, M; Seeger, J B; Jaeger, S; Mohr, G; Bitsch, R G

2012-05-01

Mechanical loosening is the most common cause of revision in unicompartmental knee arthroplasty. We determined the effect of bone lavage on tibial cement penetration and interface temperature with controlled ligament tension forces. We presumed pulsed lavage would allow increased cement penetration compared with syringe lavage. Cemented unicompartmental knee arthroplasty was performed in 12 pairs of fresh-frozen knees. Lavage was performed using pulsed lavage on one side (A) and syringe lavage on the other (B). Cement penetration pressure, interface temperature, and ligament tension forces were continuously monitored during the operation. Screened radiographs were taken and cement penetration under the tibial plateau was measured. The pulsed lavage group showed a mean cement penetration area of 187.24 (SD 36.37) mm², whereas 144.29 (SD 35.74) mm(2) was measured in the group with syringe lavage. Cement penetration pressure was 13.29 (SD 8.69) kPa in Group A and 20.21 (SD 7.78) kPa in Group B. Maximum interface temperatures of 46.99°C were observed in Group A and 45.02°C in Group B. Our data showed pulsed lavage cleansing of the cancellous tibial bone substantially improved cement penetration compared with syringe lavage without reaching the temperature threshold for bone necrosis. We recommend the routine use of pulsed lavage to improve long-term fixation. Copyright © 2011 Elsevier Ltd. All rights reserved.

New concept of 3D printed bone clip (polylactic acid/hydroxyapatite/silk composite) for internal fixation of bone fractures.

PubMed

Yeon, Yeung Kyu; Park, Hae Sang; Lee, Jung Min; Lee, Ji Seung; Lee, Young Jin; Sultan, Md Tipu; Seo, Ye Bin; Lee, Ok Joo; Kim, Soon Hee; Park, Chan Hum

Open reduction with internal fixation is commonly used for the treatment of bone fractures. However, postoperative infection associated with internal fixation devices (intramedullary nails, plates, and screws) remains a significant complication, and it is technically difficult to fix multiple fragmented bony fractures using internal fixation devices. In addition, drilling in the bone to install devices can lead to secondary fracture, bone necrosis associated with postoperative infection. In this study, we developed bone clip type internal fixation device using three- dimensional (3D) printing technology. Standard 3D model of the bone clip was generated based on computed tomography (CT) scan of the femur in the rat. Polylacticacid (PLA), hydroxyapatite (HA), and silk were used for bone clip material. The purpose of this study was to characterize 3D printed PLA, PLA/HA, and PLA/HA/Silk composite bone clip and evaluate the feasibility of these bone clips as an internal fixation device. Based on the results, PLA/HA/Silk composite bone clip showed similar mechanical property, and superior biocompatibility compared to other types of the bone clip. PLA/HA/Silk composite bone clip demonstrated excellent alignment of the bony segments across the femur fracture site with well-positioned bone clip in an animal study. Our 3D printed bone clips have several advantages: (1) relatively noninvasive (drilling in the bone is not necessary), (2) patient-specific design (3) mechanically stable device, and (4) it provides high biocompatibility. Therefore, we suggest that our 3D printed PLA/HA/Silk composite bone clip is a possible internal fixation device.

Polymeric additives to enhance the functional properties of calcium phosphate cements

PubMed Central