Cement Filler Research Articles

Sacroplasty for Symptomatic Sacral Hemangioma: A Novel Treatment Approach

Painful vertebral body hemangiomas have been successfully treated with vertebroplasty and kyphoplasty. Sacral hemangiomas are uncommon and as such painful sacral hemangiomas are rare entities. We report what we believe is only the second successful treatment of a painful sacral hemangioma with CT-guided sacroplasty. A 56-year-old woman with a history of right-sided total hip arthroplasty and lipoma excision presented to her orthopedic surgeon with persistent right-sided low back pain which radiated into her buttock and right groin and hindered her ability to walk and perform her activities of daily living. MRIs of the thoracic spine, lumbar spine and pelvis showed numerous lesions with imaging characteristics consistent with multiple hemangiomas including a 2.2×2.1 cm lesion involving the right sacrum adjacent to the right S1 neural foramen. Conservative measures including rest, physical therapy, oral analgesics and right-sided sacroiliac joint steroid injection did not provide significant relief. Given her lack of improvement and the fact that her pain localized to the right sacrum, the patient underwent CT-guided sacroplasty for treatment of a painful right sacral hemangioma. Under CT fluoroscopic guidance, a 10 gauge introducer needle was advanced through the soft tissues of the back to the margin of the lesion. Biopsy was then performed and after appropriate preparation, cement was then introduced through the needle using a separate cement filler cannula. Appropriate filling of the right sacral hemangioma was visualized using intermittent CT fluoroscopy. After injection of approximately 2.5 cc of cement, it was felt that there was near complete filling of the right sacral hemangioma. With satisfactory achievement of cement filling, the procedure was terminated. Pathology from biopsy taken at the time of the procedure was consistent with hemangioma. Image-guided sacroplasty with well-defined endpoints is an effective, minimally invasive and safe procedure. Patients with painful sacral hemangiomas can be treated with this technique with no significant complications.

Improvement of electromagnetic wave (EMW) shielding through inclusion of electrolytic manganese dioxide in cement and tile-based composites with application for indoor wireless communication systems

The electromagnetic wave absorption characteristics of composite cement-based building material have attracted much interest in recent times. Researchers have mainly focused on the 2 GHz to 12 GHz frequency range while the authors have investigated the mobile and WiFi frequency bands. The determination of characteristics such as reflection loss, absorption, attenuation and shielding effectiveness are crucial in the evaluation and development of these materials for the building industry. The authors have determined the characteristics by measuring the S11 and S21 parameters of the composite cement-based material in the Global System for Mobile (GSM) and WiFi frequency bands. MnZn-ferrite and electrolytic manganese dioxide in powder form is used as absorber material to increase the permeability of the cement-based material to improve absorption and attenuation capabilities to create a cost-effective practical electromagnetic wave absorber. The results achieved show the uniqueness of electrolytic manganese dioxide as filler in composite cement based material for electromagnetic wave shielding effectiveness improvement. Shielding of 8 dB in the GSM850 and GSM900 frequency bands and 5 dB in the GSM1800 and GSM1900 frequency bands were measured. Key words: Electromagnetic wave absorption measurement, attenuation, magnetic composites in building material, reflection loss, shielding effectiveness, transmission loss

Surface Tests to Demonstrate the Construction Feasibility of the Belgian Supercontainer

The Supercontainer (SC) is a reference concept, adopted by the Belgian Agency for Radioactive Waste and Enriched Fissile Materials (ONDRAF/NIRAS), for the packaging of high level vitrified radioactive waste (HLW) and spent fuel (SF). The waste package consists of different components all designed to fulfil specific functions. One of these is a carbon steel overpack developed to prevent contact of the waste with the engineered barrier system and the host geological formation during the thermal phase. Another is a concrete buffer and cementitious filler, both developed to provide a high pH environment during at least the thermal phase, which ensures passivation of the overpack and provides radiological shielding during construction and handling of the SC. Finally, the presence of an outer steel envelope serves as a mould for the casting of the outer buffer while providing additional mechanical strength and confinement during transportation and handling of the waste package. As part of the first safety and feasibility case (SFC-1), ONDRAF/NIRAS has to demonstrate that no fundamental flaws exist regarding the feasibility to construct the SC. To this end, ONDRAF/NIRAS established a research programme consisting of desk studies, modelling, theoretical development and experimental testing. The primary objective of the experimental testing programme is to demonstrate the feasibility to construct the SC. This paper describes the test's setup and design and provides a summary of the main observations obtained during an experimental test performed to evaluate the construction feasibility of the SC.

Performance of Cement for Immobilizing Strontium Waste in Saline Environment

For solving the radioactive waste storage problem, there is an idea to store immobilized waste at deep sea. Solidifier material, such as cement should be resistance to saline environment for deep sea storage. So, this research objective is to study the performance of cementation method in immobilizing strontium waste in saline environment. Research was conducted by immobilizing strontium waste using Portland pozzolanic cement, white cement and composite Portland cement. Cement, 65 ppm Sr(NO3)2, sand and water were mixed and cast. Strontium waste varied in 2 v/o, 4 v/o, 6 v/o and 8 v/o. After 28 days curing, the cement block’s compressive strength and leaching rate on saline water were analyzed. Determination of compressive strength was done by using Universal Wood Testing. The density of blocks was measured by picnometer at 25°C. Compressive strength test for Portland pozzolanic cement at various w/c was conducted to confirm the effect of w/c in increasing the strength. For testing strontium leaching rate in water containing 35 ppm NaCl, cement blocks have been immersed in saline water for 21 days. 25 ml samples were taken and analyzed by Atomic Absorption Spectrophotometer. Strontium leaching rate on block containing pH 9 of waste was compared to the previous research data of strontium leaching rate on water to know the effect of saline water. To adjust the pH, 1 MNaOH was added into the waste. Effects of various cement type and filler materials (sand, zeolite and baryte) on Portland pozzolanic cement were also compared. The results show that there were almost no effects of salt on immobilized strontium waste, except in pH 9 waste (0.00224 over to0.000199 g/cm2·days). Strontium leaching rates on all cemented waste still meet the IAEA’s standard, so the safety of cemented strontium waste disposal at saline environment could be ensured.

Adding fly ash microsphere to improve packing density, flowability and strength of cement paste

Fly ash microsphere (FAM) is a superfine fly ash. Being finer than cement, it can fill into the voids between cement grains. To study the effects of adding FAM, cement paste samples with FAM contents ranging from 0 to 60% and different water contents were made for packing density, flowability and strength measurements. The results showed that the addition of up to 40% FAM would significantly increase the packing density of the cementitious materials. With the voids partially filled by FAM and the same volume of water in the voids released, the addition of FAM could increase the water film thickness of the cement paste. Consequently, the addition of FAM could increase flowability at same strength, increase strength at same flowability, or increase both strength and flowability. Hence, FAM is an effective cementitious filler for improving the performance of cement paste and concrete.

Study on Physical Properties of Cement Filling Material by Ore Tailing

According to the occurrence of ore, mining use different cement filling mining, due to different filling body, in a different role in the maintenance of stope stability, so filling body required different strength. By regression analysis of filling body strength with sand ratio, slurry concentration and fine sand content, to get different body strength of different filling mining, and also can be the primary and secondary and the impact degree of various factors which impact the strength of filling body.

Effect of cement fill ratio in loosening of hip implants

Femoral loosening is one of the most prevalent causes of revision orthopedic surgeries. Cement mantle thickness has been directly correlated with femoral loosening. If the mantle is too thick, there is an increased risk of radiolucent lines and inconsistent densities. Also, the more bone that is reamed out during the procedure can lead to instability, especially if the quality of the bone is compromised due to osteoporosis. Too thin of a mantle can lead to a higher probability for cement fracture, loosening the prosthetic even further. This study has shown that there is an ideal thickness range between two to five that should be kept. From radiographic images one can measure the thickness of the cement mantle showing the loosening characteristics.

Post-processing pathways in carbon capture and storage by mineral carbonation (CCSM) towards the introduction of carbon neutral materials

Carbon dioxide capture and storage by mineral carbonation (CCSM) is a technology that can potentially sequester billions of tonnes of carbon dioxide (CO2) per year. Despite this large potential, the costs of CCSM are currently too high for a large deployment of the technology and new systems are being investigated to attempt to overcome these limitations. To improve this situation, the successful development of post-processing routes creating marketable carbon neutral products could help the deployment of mineral carbonation. This work investigates the current market for CCSM products and the role they can play in decreasing the overall cost of CCSM technology. The current global market for the raw commodities, primarily cement additives, fillers and iron ore feedstock which could be produced by rock and/or industrial waste/by-product mineralisation, is about 27.5 Gt and can be easily flooded assuming 10% of the global CO2 emissions sequestered by CCSM. The CCSM technology chosen will play a very important role in the products created, available post-processing routes and accessible markets if the resultant materials are of high purity. Low-value applications such as fill for land reclamation may represent the only viable opportunity at the current state of the technology, bearing in mind that these materials are competing with low-cost materials (i.e. crushed rock) and that the size distribution of the carbonated materials may need significant alteration to make them potentially useful. However, there is a lack of information available on the quality of the CCSM products towards access to high-value markets such as micro-silica and PCC. In summary, CCSM post-processing might be viable only in niche high-value markets, while low-value applications such as land/mine reclamation are potentially more feasible and could be able to absorb Gts of CCSM products.

Superfine cement for improving packing density, rheology and strength of cement paste

Abstract Superfine cement is a cement ground to a much higher fineness than ordinary cement. The addition of a small quantity of superfine cement to fill into the voids of ordinary cement can improve the packing density of the cement and thereby reduce the amount of mixing water needed to fill the voids. In this study, the effects of superfine cement on the packing density of cement (directly measured by a wet packing test), the water film thickness of cement paste (taken as the excess water to solid surface area ratio), and the flowability, rheology and strength of cement paste were investigated. The results showed that the addition of 10% to 20% superfine cement can significantly increase the packing density of the cement and the water film thickness of the cement paste. Such increases in packing density and water film thickness would then improve the flowability, rheology and strength of the cement paste. Hence, superfine cement is an effective cementitious filler for improving cement performance.

Preparation and Properties of Cement Mortar Modified by VAE Latex

The effect of VAE latex modification on the physical properties of cement mortar is investigated. The porosity problem in cement mortar modified by vinyl acetate ester-ethylene (VAE) copolymer emulsion was successfully resolved by reasonable defoaming technique. It is shown that the bond strength and water resistance properties of modified cement mortar are better than unmodified cement mortar. When polymer-cement ratios ranged from 0 to 0.25, the bond strength and anti-permeability increased first and then decreased. The best value appeared at 0.1(polymer-cement ratio). SEM shows that the modified sample has compacted structure, polymeric films wrap the cement body and fill in the gap between cement and sand to improve the interfacial bond.

A Medium Viscous Acrylic Cement Enhances Uniformity of Cement Filling and Reduces Leakage in Cancellous Bone Augmentation

Vertebroplasty is an efficient procedure to treat osteoporotic vertebral fractures. Cement leakage is considered to be the most severe complication during vertebroplasty. At high cement viscosities, the risk of leakage is reduced. However, injection forces are highly increased, requiring the use of high force injection systems with the lack in tactile force feedback. Therefore, an acrylic cement was developed showing medium initial viscosity and which still allows to be manually applied using syringes. An established model favoring leakage was used to observe the filling pattern and leaked cement mass. The method used included the simulation of body temperature, and all materials submitted are approved medical products. When applied just after preparation, the medium viscous cement resulted in good cement filling and less cement leakage than low viscosity cement. The added clinical value of the new cement is that the waiting time for the physician will be shortened to zero minutes without compromising the safety for the procedure.

New bioactive glass-ceramic: Synthesis and application in PMMA bone cement composites

In present study, a new composition of glass-ceramic was synthesized based on the Na2O-CaO-SiO2-P2O5 glass system. Heat treatment of glass powder was carried out in 2 stages: 600 °C as the nucleation temperature and different temperature on crystallization at 850, 950 and 1000 °C. The glass-ceramic heat-treated at 950 °C was selected as bioactive filler in commercial PMMA bone cement; (PALACOS® LV) due to its ability to form 2 high crystallization phases in comparison with 850 and 1000 °C. The results of this newly glass-ceramic filled PMMA bone cement at 0-16 wt% of filler loading were compared with those of hydroxyapatite (HA). The effect of different filler loading on the setting properties was evaluated. The peak temperature during the polymerization of bone cement decreased when the liquid to powder (L/P) ratio was reduced. The setting time, however, did not show any trend when filler loading was increased. In contrast, dough time was observed to decrease with increased filler loading. Apatite morphology was observed on the surface of the glass-ceramic and selected cement after bioactivity test.

Laboratory Evaluation of Moisture Susceptibility of Hot-Mix Asphalt Containing Cementitious Fillers

Moisture-induced damage has long been recognized as one of the major concerns for asphalt pavements. To mitigate potential moisture damage, one general method is to add mineral antistripping additives or liquid antistripping agents into hot-mix asphalt (HMA) mixtures. In this study, a comparative laboratory experiment was conducted to investigate the effectiveness of cementitious fillers on moisture susceptibility of HMA mixtures. Five types of cementitious fillers were considered: fly ash, cement kiln dust, and three types of hydrated lime with different finenesses. The laboratory performance of HMA mixtures subjected to moisture conditioning was evaluated through the following tests: dynamic modulus test; superpave indirect tensile tests; and tensile strength ratio test. The test results indicate that the cementitious fillers were generally effective in reducing the moisture susceptibility of HMA mixtures. The finer the hydrated lime particle, the more resistant the asphalt mixtures. In addition, dynamic shear rheometer test was conducted on asphalt mastics to explore the stiffening effect of different cementitious fillers.

Cement Filling Control and Bone Marrow Removal in Vertebral Body Augmentation by Unipedicular Aspiration Technique

Experimental design using a laboratory leakage model. To examine that a new aspiration technique, with a double conduit cannula design, improves the uniformity of cement filling, thus significantly reducing the risk of extraosseous leakage. In vertebral augmentation, understanding the forces governing the intravertebral cement flow is essential for controlling the cement formation. A path of least resistance posed by the irregularities in the bone matrix or vertebral shell increases the risk of leak. We have previously shown that using viscous cement reduces the leakage risk. However, this may damage the already weak bone due to the high forces required for the cement to enter the bone cavities. An experimental leakage model for vertebral augmentation was used-with a path, simulating a blood vessel, to provoke leakage. A novel cannula with 2 concentric conduits was used. The inner conduit is used for cement delivery and the outer conduit for aspiration. A mixed level with 2 factors (2 x 2(2)) experiment design was used to examine the ability of aspiration to direct the cement flow in both low and high viscous cement regimes. Aspiration significantly enhanced the filling uniformity and reduced the risk of leakage. The reduction in leak with the suction simultaneous to the injection for low viscosity cement, elapsed time 4 minutes, was 1.5 cc (alpha = 0.05). In the suction experiments, the reduction in leakage as compared with the reference condition for the 8 minutes elapsed time was 0.5 cc, (alpha = 0.05). The aspiration technique combined with a new cannula design improved the uniformity of filling. The aspiration technique helps in removal of the displaced bone marrow or tumor tissue. The aspiration applied with the new cannula requires only a single incision. Thus, it does not result in an increased invasiveness.

Lower-Pressure Percutaneous Vertebroplasty Using Larger-Diameter Bone-Cement Fillers

Study Design: This is a retrospective, case-controlled study Objective: We wanted to evaluate the efficacy of lower-pressure percutaneous vertebroplasty (LP-PVP) using larger-diameter cement fillers for treating osteoporotic vertebral compression fracture (VCF). Summary of the Literature Review: Despite the popularity of conventional PVP(C-PVP), critical complications associated with cement leakage have been widely reported due to the inadequate viscosity of flabby cement. Materials and Methods: With excluding Kummell’s disease, 23 VCF’s were treated with LP-PVP using 2.8mm-diameter cement fillers, 51 VCF’s were treated with kyphoplasty(KP) using the same size of cement fillers and 19 VCF’s were treated with C-PVP using 1.4mmdiameter biopsy needles. The clinical and radiographic results along with the complications were investigated for more than one year. Results: The visual analogue scale (VAS) was improved in all the groups. The infused cement volume was 5.9±1.6ml for the LP-PVP, 5.9±1.9ml for the KP and 3.5±1.0ml for the C-PVP (p=0.000). The collapsed vertebral height was restored by 10.8±10.3%, 13.0±12.7% and 4.7±7.6%, respectively, in each group (p=0.000) with a reduction loss of 2.1±1.8%, 1.1±1.4% and 5.9±4.2%. respectively, in each group (p=0.000) at follow-up. These was a reduction of the vertebral kyphotic angle by 3.0±4.0°, 3.7±4.4° and 4.2±4.4°, respectively, in each group (p=0.528) with reduction loss of 1.0±0.9°, 0.1±1.7° and 3.5± 2.8°, respectively, in each group (p=0.000). There was a reduction of the regional Cobb’s angle by 4.3±2.6°, 3.1±4.7° and 2.9±3.8°, respectively, in each group (p=0.184) with a reduction loss of 3.6±4.5°, 0.1±1.5° and 1.0±4.1°, respectively, in each group (p=0.000). Extravasation of cement was noticed in 6 cases (26.1%) of LP-PVP, in 14 cases (27.5%) of KP and 4 cases (26.1%) of C-PVP (p=0.689). No cases of additional VCF happened for the LP-PVP, eight cases of additional VCF happened (15.7%) for the KP and one case of additional VCF happened (5.3%) for the C-PVP (p=0.030). Conclusion: The LP-PVP showed clinically and radiologically results that were similar to those of KP with a higher amount of infused cement volume compared to that of C-PVP. LP-PVP is thought to be effective for the clinical and radiolographic aspects and to have fewer complications for the treatment of osteoporotic VCF.

Vertebroplasty

STUDY DESIGN.: Biomechanical study of vertebroplasty in cadaver motion segments. OBJECTIVES.: To determine how the volume of injected cement influences: (a) stress distributions on fractured and adjacent vertebral bodies, (b) load-sharing between the vertebral bodies and neural arch, and (c) cement leakage. SUMMARY OF BACKGROUND DATA.: Vertebroplasty is increasingly used to treat vertebral fractures, but there are problems concerning adjacent level fracture and cement leakage, both of which may depend on the volume of injected cement. METHODS.: Nineteen thoracolumbar motion segments from 13 cadavers (42-91 years) were loaded to induce fracture. Fractured vertebrae received 2 sequential injections (VP1 and VP2) of 3.5 cm of polymethylmethacrylate cement. Before and after each intervention, motion segment stiffness was measured in compression and in bending, and "stress profilometry" was used to quantify the distribution of compressive stress in the intervertebral disc (which presses equally on fractured and adjacent vertebrae). Stress profiles were obtained by pulling a pressure transducer through the disc while the motion segment was compressed in flexed and extended postures. Stress profiles yielded the intradiscal pressure (IDP), the magnitude of stress peaks in the anterior and posterior (SPP) anulus, and the percentage of the applied compressive force resisted by the neural arch (FN). Cement leakage and vertebral body volume were quantified using water-immersion, and the percentage cement fill was estimated. RESULTS.: Bending and compressive stiffness fell by 37% and 50% respectively following fracture, and were restored only after VP2. Depending on posture, IDP fell by 59-85% after fracture whereas SPP increased by 107- 362%. VP1 restored IDP and SPP to prefracture values, and VP2 produced no further changes. Fracture increased FN from 11% to 39% in flexion, and from 33% to 59% in extension. FN was restored towards prefracture values only after VP2. Cement leakage increased after VP2 and was negatively correlated to vertebral body volume. Following VP2, increases in IDP and compressive stiffness were proportional to percentage fill. CONCLUSION.: About 3.5 cm of PMMA largely restored normal stress distributions to fractured and adjacent vertebral bodies, but 7 cm were required to restore motion segment stiffness and load-sharing between the vertebral bodies and neural arch. Cement leakage, IDP and compressive stiffness all increased with percentage fill.

Micro hardness of interface between cement asphalt emulsion mastics and aggregates

Characteristics of interface between cement asphalt emulsion mastics and aggregate is different from that of interface between cement and aggregate or asphalt and aggregate. A novel method was put forward to evaluate interface character of mixtures in the paper. MH-5 micro hardness apparatus was adopted to study influences of fillers’ fineness, aggregate lithology and different type of cement on micro hardness of the interface between the mastics and aggregate; and some micro test apparatuses, such as SEM, XRD and EPMA, were used to analyze its mechanism. Results indicate that the increase of cement and mineral filler fineness is favorable to improve micro hardness of the interface, but over fine mineral filler is disadvantageous. In contrast to granite and granite filler, limestone and limestone filler are more helpful to increase the hardness value. Lithology changes of mineral filler have greater influences on the hardness than those of aggregate. The micro hardness value first increases, then decreases with the increase of mineral filler/asphalt emulsion (MF/AE) ratios. There exists an optimal ratio, which is 1.1. Adopting the high strength cement is an effective way to improve the micro hardness.

A classification of studies on properties of foam concrete

Abstract Though foam concrete was initially envisaged as a void filling and insulation material, there have been renewed interest in its structural characteristics in view of its lighter weight, savings in material and potential for large scale utilization of wastes like fly ash. The focus of this paper is to classify literature on foam concrete in terms of constituent materials (foaming agent, cement and other fillers used), mix proportioning, production methods, fresh and hardened properties of foam concrete. Based on the review, the following research needs have been identified: (i) developing affordable foaming agent and foam generator, (ii) investigation on compatibility between foaming agent and chemical admixtures, use of lightweight coarse aggregate and reinforcement including fibers, (iii) durability studies, and (iv) factors influencing foam concrete production viz., mixing, transporting and pumping.

Magnesium-Based Bone Cement and Bone Void Filler

Bone cement has great potential in craniofacial surgery in the repair of osseous defects secondary to surgery or trauma. This includes the use of bone cement as a bone void filler for full-thickness cranial defects and as augmentation of deficient bones. Ideally, this material should be easily available, biocompatible, resorbable, bone inductive, and have adhesive qualities to bone. Calcium-based bone cements have some of these qualities but have a higher than desirable failure rate. OsteoCrete, a new magnesium-based bone cement and bone void filler, was compared to Norian in critical-sized skull defects and cementing bone flaps in rabbits. Both materials were successful; however, OsteoCrete had a faster resorption and replacement by bone rate than Norian. Bone flap position and apparent stability were also superior with OsteoCrete. There were no adverse reactions to either cement. A magnesium-based bone cement presents with advantages when compared with a comparator calcium-based cement in craniofacial surgery.

Differences in endplate deformation of the adjacent and augmented vertebra following cement augmentation

Vertebral cement augmentation can restore the stiffness and strength of a fractured vertebra and relieve chronic pain. Previous finite element analysis, biomechanical tests and clinical studies have indirectly associated new adjacent vertebral fractures following augmentation to altered loading. The aim of this repeated measures in situ biomechanical study was to determine the changes in the adjacent and augmented endplate deformation following cement augmentation of human cadaveric functional spine units (FSU) using micro-computed tomography (micro-CT). The surrounding soft tissue and posterior elements of 22 cadaveric human FSU were removed. FSU were assigned to two groups, control (n = 8) (loaded on day 1 and day 2) and augmented (n = 14) (loaded on day 1, augmented 20% cement fill, and loaded on day 2). The augmented group was further subdivided into a prophylactic augmentation group (n = 9), and vertebrae which spontaneously fractured during loading on day 1 (n = 5). The FSU were axially loaded (200, 1,000, 1,500-2,000 N) within a custom made radiolucent, saline filled loading device. At each loading step, FSUs were scanned using the micro-CT. Endplate heights were determined using custom software. No significant increase in endplate deformation following cement augmentation was noted for the adjacent endplate (P > 0.05). The deformation of the augmented endplate was significantly reduced following cement augmentation for both the prophylactic and fracture group (P < 0.05, P < 0.01, respectively). Endplate deformation of the controls showed no statistically significant differences between loading on day 1 and day 2. A linear relationship was noted between the applied compressive load and endplate deflection (R (2) = 0.58). Evidence of significant endplate deformation differences between unaugmented and augmented FSU, while evident for the augmented endplate, was not present for the adjacent endplate. This non-invasive micro-CT method may also be useful to investigate endplate failure, and parameters that predict vertebral failure.