Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Bone Cements”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 541 records · Page 30Linked to original sources
PubMed1997

Integrated system for preparation of bone cement and effects on cement quality and environment.

We developed a prepacked mixing system for the preparation of bone cement. The system is based on mixing and collection of bone cement under a vacuum and serves as both the storage and mixing device for the cement components, thereby minimizing the exposure of the operating staff to the monomer and the risk for contamination of the cement during preparation. We evaluated the system using Palacos R and Simplex P. The cement produced was compared with cement obtained from a commercially available mixing system. Temperature evolution during curing, handling characteristics, density, and porosity of the cement obtained were analyzed. The results showed that the experimental system produces cement with physical properties (i.e., setting times and temperature, porosity, and density) equal to or better than those obtained with commercially available systems. Reducing the amount of monomer in the experimental system led to a reduction of the curing temperature without compromising the physical properties of the cements.

Biocompatible Materials↗
PubMed1998

Comparison between the polymerization behavior of a new bone cement and a commercial one: modeling and in vitro analysis.

The polymerization behavior of a new bone cement based on poly(ethylmethacrylate), hydroxyapatite powder and n-butylmethacrylate monomer and a commercial cement have been studied. Polymerization kinetics were analyzed by means of differential scanning calorimetry (DSC). DSC data have been used to evaluate a phenomenological model describing the cure kinetics of this new bone cement. The kinetic model coupled with the energy balance was then used to obtain temperature and degree of conversion profiles in the bone-cement-prosthesis system, under non-isothermal conditions, as function of initial temperature and thickness of the cement. Material properties, boundary and initial conditions and the kinetic behavior were the input data for the numerically solved heat-transfer model. The modeling results have been compared with in vitro results.

Journal Article↗
PubMed1994

Experimental studies on a new bioactive bone cement: hydroxyapatite composite resin.

We developed hydroxyapatite composite resin (CAP) as a new type of bioactive bone cement. CAP is composed of 80% w/w hydroxyapatite granules (mean particle size: 2 microns) and bis-phenol-A glycidyl methacrylate-based resin. The setting time is 5 min and the peak curing temperature during polymerization is 46 degrees C. In this study, the mechanical strength of CAP and the biological behaviour of the CAP-bone interface were examined. The compressive strength of CAP was 260 MPa and this was about three times greater than that of commercial polymethylmethacrylate (PMMA) bone cement. The tensile strength and fracture toughness of CAP also exceeded those of PMMA cement. CAP was implanted into the femoral condyles of rabbits. Two weeks later, new bone formation was already seen on the surface of the CAP implants. At 8 wk, bone was growing directly onto the surface of the CAP implants and no intervening fibrous tissue could be observed at the CAP-bone interface. These results show that CAP is a promising material which possesses superior mechanical strength and the biological property of achieving direct contact with bone.

Animals↗
PubMed1993

An investigation of bone necrosis and healing after cryosurgery, phenol cautery or packing with bone cement of defects in the dog femur.

A corticocancellous core was removed from the lateral condyle of both femurs in 26 skeletally mature dogs. The cavity was treated with cryosurgery, phenol cautery or packing with bone cement. The animals were killed after 1, 4, and 12 weeks in the phenol and cement groups, and also after 24 weeks in the cryosurgery group. The extent of the bone necrosis and healing was assessed in each group. After cryosurgery the extent of necrosis was profound in that the area of damage was 365% compared to the area of the cavity; the depth of necrosis extended between 2.5 and 14 mm, beyond the cavity wall. The effect of phenol was negligible in that only microscopic areas of superficial focal necrosis were found around the cavity wall. Bone cement produced an area of necrosis of 153% compared with the cavity, with a depth of between 1.3 and 2.8 mm. Regeneration in the region of necrosis after cryosurgery was only scanty by 4 weeks, but by 12 weeks considerable areas of regeneration were identified and complete healing was observed by 24 weeks. Regeneration of the necrotized bone produced by bone cement packing was rapid and similar to that of the control specimens. These findings suggest that cryosurgery could play a significant role as a surgical adjunct to curettage in locally aggressive benign bone tumours and in some malignancies. Phenol cautery is not regarded as an adequate treatment after curettage of bone tumours. Although the extent of necrosis was relatively small, packing with bone cement is thought to be a useful choice in benign cases.

Animals↗
PubMed2006

Graft copolymers of methyl methacrylate and poly([R]-3-hydroxybutyrate) macromonomers as candidates for inclusion in acrylic bone cement formulations: Compression testing.

Graft copolymers of methyl methacrylate and biodegradable, biocompatible bacterial poly([R]-3-hydroxybutyrate) (PHB) blocks were synthesized and evaluated as possible constituents in acrylic bone cements for use in orthopaedic applications. The copolymers were produced by conventional free radical copolymerization and incorporated in one commercially available acrylic bone cement brand, Antibiotic Simplex (AKZ). Cements with formulations containing 6.7 and 13.5 wt % of PMMA-graft-PHB were prepared. The morphology of the graft copolymer particles was suggested to influence the ability of the modified cement to be processed. Formulations containing more than about 20 wt % of the graft copolymer resulted in cement doughs that, both after first preparation and several hours later, were either sandy or soft spongy in texture and, thus, would be unacceptable for use in orthopaedic applications. The morphologies of the powders and the volumetric porosity (p) and ultimate compressive strength (UCS) of the cured cements were determined. Micro computed tomography showed that the cements presented average porosities of 13.5-16.9%. It was found that, while the powder particle shape and size for the experimental cements were markedly different from those of AKZ, there was no significant difference in either p or UCS for these cements. The latter was determined to be about 85 MPa for the modified cements and 84 MPa for Antibiotic Simplex. Furthermore, the UCS of all the cements exceeded the minimum level for acrylic bone cements, as stipulated by ASTM F-451.

Biocompatible Materials↗
PubMed1977

A longitudinal study of the radiolucent line at the bone-cement interface following total joint-replacement procedures.

After 100 consecutive total hip arthroplasties, a radiolucent line at the bone-cement interface as seen on serial roentgenograms was on the acetabular side in fifty-nine hips and on the femoral side, in three. Similarly, after seventy-five consecutive non-hinged knee-replacement arthroplasties, a radiolucent line was found at the bone-cement interface beneath the polyethylene component more frequently in knees in which the more constrained geometric implant was used (forty-two of fity-nine) than in knees in which the less constrained polycentric and modular prostheses were used (three of sixteen). The presence of a lucent line at the bone-cement interface in these joints did not signify looseness or failure of the arthroplasty.

Bone Cements↗
PubMed2005

Use of Mimix hydroxyapatite bone cement for difficult ossicular reconstruction.

OBJECTIVE: To describe the advantages of using Mimix hydroxyapatite (HA) bone cement in reconstructing a variety of ossicular chain abnormalities. STUDY DESIGN AND SETTING: Case series at a tertiary medical center. RESULTS: Twenty-five cases of HA reconstruction are included in this series (ages 23-74; mean, 47 years). The examples presented include (1) HA as the sole reconstructive material for incus erosion, (2) HA for securing a total or partial ossicular replacement prosthesis, (3) incus augmentation after crimping for revision stapedotomy with incus erosion, (4) HA in primary stapedotomy to fix the crimped prosthesis to an intact incus, and (5) other unique situations. Preoperative and postoperative audiograms were evaluated for 4-tone pure tone average (PTA), speech reception thresholds, word recognition scores, and air-bone gaps (AB gaps). Mean follow-up was 11 months (range 2 to 22 months). The mean PTA improved from 57 dB to 37 dB, whereas the mean AB gaps decreased from 33 dB to 16 dB. There were no cases of infection or extrusion. CONCLUSIONS: Hydroxyapatite bone cement is an excellent adjunct or alternative to ossiculoplasty with preformed prostheses. Easily malleable, rapidly setting, and rapidly hardening, Mimix is particularly well suited for middle ear work. SIGNIFICANCE: Definitive fixation with bone cements during difficult ossicular chain reconstruction may ensure a more enduring successful outcome.

Adult↗
PubMed1980

[Bone reaction to metal and bone cement implants at immunologic reaction level in rats (author's transl)].

After the fact that femoral osteotomy in rats results in destruction of the entire bone (in the majority of experimental animals) due to an immunological reaction by means of Complete Freund's Adjuvant, we have investigated whether or not the implantation of bone cement or Kirschner wires affects additionally the condition of the bone. We have found that bone cement or metallic material within the bone cavity aggravates osteolysis if there is an immunologic reaction present. The conditions of the immunologic mechanism and the applied orthopedic procedures are discussed and an attempt has been made to explain the phenomenon.

Animals↗
PubMed1986

In vivo versus in vitro polymerization of acrylic bone cement: effect on material properties.

Flexural strength and molecular weight of polymethylmethacrylate bone cement were determined for cement polymerized in vivo in a canine total hip replacement and cement from the same batch polymerized in vitro. Both in vivo and in vitro samples showed a slight increase in flexural strength and modulus at 2 weeks, followed by a nearly equivalent decline at 8 weeks. In vitro and in vivo samples exhibit a comparable stress to failure, but the in vivo samples show a significantly increased strain and decreased modulus. Cement from the proximal region of the prosthesis has significantly decreased flexural strength, lower modulus, and lower molecular weight than cement from the distal region and plug, suggesting that failures in the proximal region of a prosthesis may be due to inferior physical and mechanical properties of the bone cement in that region.

Animals↗
PubMed1983

Biochemical features of pseudomembrane at the bone-cement interface of loosened total hip prostheses.

Biochemical features of pseudomembrane formed at the bone-cement interface of 13 failed total hip replacements were studied and histological examination of the pseudomembrane was conducted. The results of biochemical analyses revealed on average hydroxyproline, 86 micrograms/mg; water content, 57%; hexosamine, 12 micrograms/mg; glucosamine/galactosamine, 1.4%; and calcium, 2.1%. Approximately 78% of collagen was extracted with pepsin, whereas only 8 and 0.3% collagen were extracted with acetic acid and neutral salt, respectively. On further differential salting out of the extracted collagen, about 77% was type I collagen, 19% type III, and 2.6% type V. Unlike pseudoarthrosis of fracture, no type II collagen was identified. Overall biochemical features in the light of the histological appearance suggested that pseudomembrane resembles granulation tissue. Bone healing mechanisms at the bone-cement interface appear to differ from that of fracture healing.

Adult↗
PubMed1992

A fractographic investigation of PMMA bone cement focusing on the relationship between porosity reduction and increased fatigue life.

Fracture surfaces of both monotonic and fatigue loaded bone cement samples were examined to investigate the fractographic characteristics of PMMA. Classic cleavage step river patterns were observed on all monotonically loaded samples, running downstream in the direction of crack propagation. All fatigue cracks initiated at internal pores and the direction of crack propagation of many cracks was discernible. Porosity, pore size, and pore size distribution were found to affect the crack initiation and fatigue behavior of bone cement. Statistical analysis revealed a strong negative correlation between two-dimensional porosity present on the fracture surfaces and the cycles to failure. The fractographic observations of these fatigue samples elucidate one reason why porosity reduction by centrifugation or vacuum mixing increases the fatigue life of PMMA bone cement.

Biocompatible Materials↗
PubMed2003

Increased release of gentamicin from acrylic bone cements under influence of low-frequency ultrasound.

The release profile of antibiotics from antibiotic-loaded bone cement, used to prevent infections in total joint arthroplasty, is neither ideal nor complete. Ultrasound has been used to allow drugs to cross otherwise impermeable barriers. The aim of this study was to establish a possible effect of ultrasound on antibiotic release from bone cements. Samples were made of three commercially available gentamicin-loaded bone cements. Part of the samples was allowed to release gentamicin for 3 weeks before insonation. An insonation device produced an ultrasound field with a time average acoustic intensity of 167 mW/cm2 at a frequency of 46.5 kHz. The samples were exposed to the ultrasound field or not exposed to it as a control. The amount of gentamicin released was measured by fluorescence polarization immunoassay. There was a limited increase of gentamicin release with application of ultrasound in fresh samples but not in the samples that had been allowed to release gentamicin. For fresh samples, a linear regression model showed that this ultrasound effect was statistically significant. The mechanism behind these observations is not clear, but it is suggested that microstreaming or localized temperature rises may be involved.

Delayed-Action Preparations↗
PubMed1990

Cefuroxime in total joint arthroplasty. Intravenous or in bone cement.

A prospective randomized clinical trial was performed in two centers to compare the effect of systemic cefuroxime and cefuroxime in bone cement in the prophylaxis of infection after total joint arthroplasty. In two comparable groups comprising 200 and 201 patients, there was no statistically significant difference in the incidence of superficial wound infection. The early deep infection rate was 1%, with no difference detected between the group that received antibiotic in bone cement and the group that received systemic antibiotic. There were no late deep infections. It is concluded that cefuroxime given systemically or in bone cement is an effective antibiotic in the prophylaxis of infection after total joint arthroplasty.

Aged↗
PubMed1989

Modern cementing techniques. An experimental study of vacuum insertion of bone cement.

The results of these experiments show that an increase in the intramedullary pressure (IMP) can lead to embolization of bone marrow contents via the venous drainage system along the linea aspera. A vacuum applied distally to the medullary canal is very effective for filling the diaphyseal tube with cement. The cancellous bone honeycombs of the proximal metaphysis, however, can only be filled if the bone sponge is tunneled at the level of the femoral calcar; a proximal vacuum then yields filling of the cancellous bone framework with bone cement. In order to fill the weight-bearing spongious framework of the pelvic bone with cement, the acetabular cavity should be sealed with a rubber ring and vacuum applied proximo-laterally to the ilium, thereby giving an extremely high suction pressure.

Animals↗
PubMed1999

ESR study of MMA polymerization by a peroxide/amine system: bone cement formation.

Electron spin resonance (ESR) spectroscopy was used to gain insight at the molecular level into the curing of bone cement. Methyl methacrylate was polymerized using a N,N-dimethyl-p-toluidine (TD)/benzoyl peroxide (BPO) redox system in the presence of polymethyl methacrylate (PMMA) powder. The conventional nine-line ESR spectrum for the growing polymer radical was detected at the gel stage of polymerization. While the optimum free radical concentration was observed near the equimolar amine/BPO concentration, excess amine led to a change in the chemical structure of the trapped radical and inhibited the polymerization process. At a high amine/BPO ratio the nine-line signal disappeared and a three-line nitroxide-based radical appeared. The appearance of this nitroxide signal seems to depend on the amine/BPO molar ratio and on the presence of PMMA. An excess amount of amine with respect to BPO was found to inhibit the polymerization process. When BPO was removed, the system still polymerized but with a longer gelation time and a lower radical concentration. These results demonstrate that trapped free radicals in the bulk polymerization of MMA convert to polymeric peroxides that act as initiators in bone cement. When the accelerator 4-dimethylamino phenethyl alcohol (TDOH) was used, a higher radical concentration was observed in the polymerizing system. TDOH shows potential for being a more effective accelerator than TD for bone cement curing.

Amino Alcohols↗
PubMed2000

Biological and mechanical properties of PMMA-based bioactive bone cements.

We reported previously that a bioactive PMMA-based cement was obtained by using a dry method of silanation of apatite-wollastonite glass ceramic (AW-GC) particles, and using high molecular weight PMMA particles. But handling and mechanical properties of the cement were poor (Mousa et al., J Biomed Mater Res 1999;47:336-44). In the present study, we investigated the effect of the characteristics of PMMA powder on the cement. Different cements containing different PMMA powders (CMW1, Surgical Simplex, Palacos-R and other two types of PMMA powders with Mw 270,000 and 1,200,000) and AW-GC filler in 70 wt% ratio except Palacos-R (abbreviated as B-CMW1 and B-Surg Simp, B-Palacos 50 [50 wt% AW-GC filler] and B-Palacos 70 [70 wt% AW-GC filler], B-270 and B-1200) were made. Dough and setting times of B-CMW1, B-Surg Simp B-270 and B-1200 were similar to the commercial CMW1 cement which did not contain bioactive powder (C-CMW1), but B-palacos which contained large PMMA beads with high Mw had delayed setting time. B-270 had the highest bending strength among the tested cements. After 4 and 8 weeks of implantation in the medullary canals of rat tibiae, the bone-cement interface was examined using SEM. The affinity index of B-1200 was significantly higher than the other types of cements. B-270 showed good combination of handling properties, high mechanical properties and showed higher bioactivity with minimal soft tissue interposition between bone and cement compared with commercial PMMA bone cement. This may increase the strength of the bone-cement interface and increase the longevity of cemented arthroplasties.

Animals↗
PubMed1989

[Clinical application of bone cement in cranioplasty].

Cranioplasty usually performed in case of skull defect after craniocerebral injuries. Plexiglass or metal plate were used frequently in our country. This article introduces a new kind of material--bone cement--for skull restoration. 152 cases of skull defects were repaired by bone cement in our clinic. The advantages as below: (1) Bone cement is easy to mould and good in cosmetic result; (2) It's mechanical functions are reliable; (3) Less irritant to the surrounding tissues. The procedures of the operation and principles in utilizing this material were present in detail.

Animals↗
PubMed1993

Rheumatoid nodules at the cement-bone interface in revision arthroplasty of rheumatoid patients.

We studied the histology of the cement-bone interface and the regenerated synovium in ten aseptically loosened arthroplasties in rheumatoid patients. In two patients we found rheumatoid nodules at the cement-bone interface and marked lymphoplasmacytic infiltration in another three. Failed joints in osteoarthritic patients did not show these changes, and it seems likely that the presence of abundant immunocompetent cells was due to the background disease. We speculate that rheumatoid inflammation contributed to the process of loosening.

Adult↗