Acrylic bone cement

IL6 An article related to acrylic bone cements [Abboud, M. et al PMMA-based composite materials with reactive ceramic fillers IV. Radiopacifying particles embedded in PMMA beads for acrylic bone cements, J. Biomed. Mater. Res., 53(6), 728 (2000)] provides the following information on the PMMA matrix used in these cements M, = 295,000 My,/Mn = 2.2. Calculate the number average degree of polymerization for the PMMA used in this study. 

The acrylic bone cements have been widely used to successful prosthesis in total joint replacements for the last few decades. While the surgical replacement is very successful, the bone cement is often found as a failed material after long-term use. 

It has been well known that weak interfaces between the inorganic fillers and the organic matrix reduce the mechanical strength of bone cement [38,40,44,45]. The interfacial adhesion strength can be enhanced by plasma treatment, which is generally due to the improved wettability and possibly to the chemical bonds between the filler and the resin [46,47]. Especially in acrylic bone cement, chemical bonds may have an important role in improving the mechanical strength by the plasma treatment. 

Some investigators suggested that implantation of acrylic bone cement into the femur increases plasma histamine, which, especially in elderly patients with pre-existing cardiac diseases and/or hypovolemia, can cause serious, sometimes fatal, cardiovascular complications (9). 

Sensitization can occur in patients, surgeons, and dentists and is occasionally reported (15). As most surgical gloves do not provide a reliable barrier, additional gloves are recommended. Contact dermatitis, dizziness, and nausea and vomiting occur. Ethylene oxide present in acrylic bone cement can cause acute allergic reactions in sensitized patients (16). 

Addition of materials (for example antimicrobial drugs or radio-opaque contrast materials) to acrylic bone cement can cause mechanical weakness due to loss of homogeneity and greater water resorption. Antimicrobial drugs have been added to combat the problem of microbial adherence. However, this can lead to a considerable dead biofilm mass on the polymethylmethacrylate surface, promoting late infections by providing a surface attractive to other strains of bacteria (17). 

Rumpf KW, Rieger J, Jansen J, Scherer M, Seubert S, Seubert A, Sellin HJ. Quincke s edema in a dialysis patient after administration of acrylic bone cement possible role of ethylene oxide allergy. Arch Orthop Trauma Surg 1986 105(4) 250-2. 

Comments methyl methacrylate forms the basis of acrylic bone cements used in orthopedic surgery. 

The heat of reaction for the system (20 mcal/mg) Is comparable to the acrylic bone cements (19.3 mcal/mg for Zimmer and... 

Brochu, A. B. W. Chyan, W. J. Reichert, W. M. Microencapsulation of 2-octylcyanoacrylate tissue adhesive for self-healing acrylic bone cement. Journal of Biomedical Materials Research, Part B Applied Biomaterials (2012), 100B(7), 1764-1772. 

Bone cements are widely used to anehor implants, such as knee or hip replacement. They are typically viscous liquids or pastes, and able to cure with time in situ. Newly developed degradable eements also aim to be employed as scaffolds for bone repair and regeneration. The bone cements discussed here include an acrylic bone cement that is not degradable and a PPF-based cement that is biodegradable. 

Chemical structure of PMMA powder and liquid MMA monomer used in acrylic bone cement. 

Graham, J., Pruitt, L., Ries, M. Gundiah, N. (2000) Fracture and fatigue properties of acrylic bone cement - the effects of mixing method, sterilization treatment, and molecular weight. Journal of Arthroplasty, 15, 1028-1035. 

Lewis, G. (1997) Properties of acrylic bone cement State of the art review. Journal of Biomedical Materials Research, 38, 155-182. 

Murphy, B. P. Prendergast, P. J. (2000) On the magnitude and variability of the fatigue strength of acrylic bone cement. International Journal of Fatigue, 22, 855-864. 

McLaren A.C. 2004. Alternative materials to acrylic bone cement for delivery of... 

HiU J, Orr J, Dunne N. In vitro study investigating the mechanical properties of acrylic bone cement containing calcium carbonate nanoparticles. J Mater Sci Mater Med 2008 19 3327-33. 

Marrs B, Andrews R, RanteU T, Pienkowski D. Augmentation of acrylic bone cement with multiwall carbon nanotubes. J Biomed Mater Res A 2006 77A 269-76. 

Nien YH, Huang CL. The mechanical study of acrylic bone cement reinforced with carbon nanotube. Mater Sci Eng B 2010 169 134-7. 

Harper EJ, Bonfield W (2000) TtarsUe eharacteristics of ten commercial, acrylic bone cements. J Biraned Mater Res 53(5) 605-616... 

Migliaresi C, Fambri L, Kolarik J (1994) Polymerization kinetics, glass transition temperature and creep of acrylic bone cements. Biomaterials 15 875—881... 

No.l,Jan.2003, p.79-87 GENTAMICIN RELEASE FROM MODIFIED ACRYLIC BONE CEMENTS WITH LACTOSE AND HYDROXYPROPYLMETHYLCELLULOSE... 

Cemoits and Adhesives.— Information on the role of acrylic bone cements in joint prostheses has already been given (see p. 419). However two related papers are worthy of mention in this more general context. The first discusses the clinical influences on the release of monomer from bone cement" and the second is concerned with the fate of methyl methacrylate in blood." Bayne et al. have primarily concerned themselves with effects associated with the preparation of the methyl methacrylate dough moulding compound immediately prior to use and shown that this does affect the amount of monomer available for release into the blood stream. Rejke et aU on the other hand have used gas-liquid chromatography to study the relative concentrations of methyl methacrylate monomer in cells and plasma as a function of time. 

In contrast to conventional acrylic bone cements, which are considered to be bioinert, bioactive systems should have a desirable influence on the host tissue they should initiate the formation of new bone. Moreover, a partial degradation of the matrix polymer should guarantee a good interlocking between bone and implant. As an example. Fig. 8.2 shows the bone-implant interface, where the implant consists of a self-curing, partially degradable matrix polymer that is flUed with bioactive hydroxyapatite (HA) particles. 

Gotten A, Deprez X, Migaud H et al (1995) Malignant acetabular osteolyses percutaneous injection of acrylic bone cement. Radiology 197 307-310 Gotten A, Boutry N, Cortet B et al (1998) Percutaneous vertebroplasty state of the art. Radiographics 18 311-320 discussion 320-313... 

In cemented total joint arthroplasties, acrylic bone cement functions as the piima ry load bearing material used to transfer loads from the implant to the bone. Bone cement Is formed from an exothermic reaction of benzoyl peroxide initiator present In polymethylmethacrylate powder (PMMA) and AI,AI-dimethyl-p-tolui-dene In methylmethacrylate monomer liquid (MMA), resulting in polymerization of PMMA to form a solid cement matrix. The in vivo integrity and performance of bone cement Is necessary for longevity of orthopedic implants, because it is believed that mechanical failure of the bone cement layer can lead to aseptic loosening of the Implant [101]. 

Orthopedic Adhesives/Bone Cements. Acrylic bone cements [198] are the only group of materials currently used to anchor long-term implantable devices to the neighboring bone. Though the bone cements have drawbacks, including trauma created by a highly exothermic hardening process, over 90 % of hip and knee repairs function well for 15 years. The bone cements consist of separate powder and liquid components which are mixed carefully prior to application. 

The other acrylate bone cement is based on poly-ethylmethacrylate (PEMA) and n-butylmethacrylate ( -BMA) monomer [61], Comparing to PMMA cement, less heat is produced during polymerization of the PEMA-n-BMA cement, and the polymer has a relatively low modulus and high ductility to reduce the issue of fracture. The biocompatibility of the PEMA-n-BMA cement has been excellent [62]. But these bone cements have been found to be susceptible to creep. To improve creep resistance, bioactive HA particles were incorporated [63]. Although HA improved bioactivity and creep behavior of the cement, the cement failed at lower number of cycles. 

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