PMMA bone cement

The PMMA bone cement is formed from a mixture of prepolymer PMMA powder, which contains a free-radical initiator, and liquid MMA monomer. In the operating theatre the powder and liquid are mixed, causing the initiator to dissolve and bring about polymerisation in the monomer component. The powder pre-polymer does not dissolve in the monomer but remains in the newly polymerised materials as a kind of reinforcing filler. 

Bioactive PMMA bone cement prepared by modification with methacryloxypropyltrimethoxy silane and calcium chloride. Journal of Biomedical Materials Research, 67A, 1417-1423. 

Type of commercial PMMA bone cement the cements studied were Simplex, Zimmer and Palacos. 

Effect of type of PMMA bone cement Zimmer 10.38 0.446 0.7560 0.9445 0.9790... 

Figure 30.23 Fatigue life of PMMA bone cement with various kinds of plasma-treated X-ray opaque powder at 23 MPa maximum applied stresses under flexural loading.

In the above section, effect of the interface between the X-ray-opaque filler and PMMA matrix has been investigated. In other words, no additional ingredient was added to the conventional PMMA bone cement recipe. In this section, our attention is focused on effect of the interface between milled carbon fiber and the bone cement matrix. Measurement of fatigue properties such as fatigue failure cycle deals with... 

Figure 30.27 Time to reach the maximum temperature during the polymerization of PMMA bone cement as a function of peroxide concentration on the plasma-treated X-ray opaque powder surfaces.

Kim, H.Y. Yasuda, H.K. Improvement in fatigue properties of PMMA bone cement by means of plasma surface treatment of fillers. J. Biomed. Mater. Res. (Appl. Biomater.) 1999, 48, 135-142. 

The durability of cemented joint replacements depends on the properties of PMMA bone cement. A titanium fiber was used to reinforce the cement. Before the cement was applied it was centrifuged to remove entrapped air which would cause voids in the connection. The treatment also improved the ductility of the cement. Similar processes are used in many plastic industries to improve elastic properties. 

PMMA bone cement polymethylmethacrylate based cement for the fixation of endoprostheses... 

Fixation of implants with polymethylmethacrylate (PMMA, bone cement) provides immediate stabihty, allowing patients to bare aU of their weight on the extremity at once. In contrast, implants which depend on bone ingrowth require the patient to wait about 12 weeks to bear full weight. 

PMMA bone cement, primarily used in hip and knee replacement surgery, remains an important use of PMMA polymer in medicine. The bone cement consists of PMMA (polymer) and methyl methacrylate monomer that is mixed with initiator at the time of surgery. The dough-like mixture is inserted into a... 

A few other ceramic nanoparticles have been studied to date for orthopedic applications, most of which, however, are used as additives to other orthopedic materials. For example, bare or functionahzed magnesium oxide, zirconia, barium sulfate, and calcium carbonate are added to polymethylmethacrylate (PMMA) bone cement to reduce the exothermic effect of PMMA while increase its cytocompatibility. X-ray radiopac-ity, as well as antibacterial potential [65],... 

Calcium carbonate nanoparticles are also added to PMMA bone cement to increase its mechanical properties. A study by Hill et al. evaluated the efficacy of adding... 

The bioactivity of the PCL-Si02 hybrid system demonstrated by the formation of a layer of hydroxyapatite on the surface of samples soaked in a fluid simulating the composition of human blood plasma [358, 361]. Studies on the bioactivity of PMMA-Si02 nanohybrid materials has indicated that they are suitable materials for use as bioactive bone substitutes or as nanofillers for PMMA bone cement [362]. 

Besides having an inert material for fibroblastic cells observed at the bone-cement interface, PMMA is still the current standard for cement-held prostheses. Vallo and his group measured the flexural, compressive, and fracture properties of PMMA bone cements that incorporated various amounts of HAp. They found that addition of up to 15 wt% HAp increases the flexural modulus and fracture toughness [89]. It was also observed that, with increasing HAp incorporation into PMMA, the biological responses of the bone cement increased and thus increased osteoblast adhesion and response [88]. Kwon and coworkers reported that a PMMA/HAp composite with 30 wt% of HAp increased the interfacial shear strength at the bone-implant interface 6 weeks after implantation in rabbits [101]. Several other research studies revealed that, depending on the type of bone cement, the addition of HAp can improve the mechanical properties of bone cements [102]. 

Kim SB, Kim YJ, Yoon TL (2004) The characteristics of a hydroxyapatite-[Pg.165]

Orthopaedic surgeons must fill defects created by trauma, removal of cancerous tumors, or abnormal development. Bone replacement and fixation are also issues for plastic surgeons in craniofacial procedures, hand and foot deformities, and extremity injuries. Though poly(methyl methacrylate) (PMMA) bone cement is currently in use to address these problems, it in nonbiodegradable, remaining in... 

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