Influence of the radiopacifier in an acrylic bone cement on its mechanical, thermal, and physical properties: Barium sulfate‐containing cement versus iodine‐containing cement

Abstract

In all acrylic bone cement formulations in clinical use today, radiopacity is provided by micron-sized particles (typical mean diameter of between about 1 and 2 microm) of either BaSO(4) or ZrO(2). However, a number of research reports have highlighted the fact that these particles have deleterious effects on various properties of the cured cement. Thus, there is interest in alternative radiopacifiers. The present study focuses on one such alternative. Specifically, a cement that contains covalently bound iodine in the powder (herein designated the I-cement) was compared with a commercially available cement of comparable composition (C-ment3), in which radiopacity is provided by BaSO(4) particles (this cement is herein designated the B-cement), on the basis of the strength (sigma(b)), modulus (E(b)), and work-to-fracture (U(b)), under four-point bending, plane-strain fracture toughness (K(IC)), Weibull mean fatigue life, N(WM) (fatigue conditions: +/-15 MPa; 2 Hz), activation energy (Q), and frequency factor (ln Z) for the cement polymerization process (both determined by using differential scanning calorimetry at heating rates of 5, 10, 15, and 20 K min(-1)), and the diffusion coefficient for the absorption of phosphate-buffered saline at 37 degrees C (D). For the B-cement, the values of sigma(b), E(b), U(b), K(IC), N(WM), Q, ln Z, and D were 53 +/- 3 MPa, 3000 +/- 120 MPa, 108 +/- 15 kJ m(-3), 1.67 +/- 0.02 MPa check mark m, 7197 cycles, 243 +/- 17 kJ mol(-1), 87 +/- 6, and (3.15 +/- 0.94) x 10(-12) m(2) s(-1), respectively. For the I-cement, the corresponding values were 58 +/- 5 MPa, 2790 +/- 140 MPa, 118 +/- 45 kJ m(-3), 1.73 +/- 0.11 MPa check mark m, 5520 cycles, 267 +/- 19 kJ mol(-1), 95 +/- 9, and (3.83 +/- 0.25) x 10(-12) m(2) s(-1). For each of the properties of the fully cured cement, except for the rate constant of the polymerization reaction, at 37 degrees C (k'), as estimated from the Q and ln Z results, there is no statistically significant difference between the two cements. k' for the I-cement was about a third that for the B-cement, suggesting that the former cement has a higher thermal stability. The influence of various characteristics of the starting powder (mean particle size, particle size distribution, and morphology) on the properties of the cured cements appears to be complex. When all the present results are considered, there is a clear indication that the I-cement is a viable candidate cement for use in cemented arthroplasties in place of the B-cement.

Chemical structure of methylmethacrylate-2-[2′,3′,5′-triiodobenzoyl]oxoethyl methacrylate copolymer, radio-opacity, in vitro and in vivo biocompatibility

“…Taken together, these results suggest that the copolymer is formed by blocks of pMMA intercalated by some units of TIBOM. Several authors have tried other iodinated acrylic monomers to increase radio-opacity, specifically 2-[4-iodobenzoyl]-oxo-ethylmethacrylate [17], 2,5-diiodo-8-quinolyl methacrylate [15] and 3,5-diiodine salicylic methacrylate [9], and also the addition of iodinated molecules dissolved in the cement, such as odixanol, iohexol and iohexol acetate [16]. The radio-opacity obtained with TIBOM is obtained with a smaller amount of monomer since it contains three atoms of iodine.…”

“…Several authors have proposed the use of copolymers containing monomers with covalently bound iodine, which ensure radio-opacity, in the preparation of radio-opaque cements or embolization beads [14][15][16][17][18][19][20][21]. Iodine is known to be radio-opaque due to its high atomic weight (relative atomic mass = 127).…”

The effect of vacuum mixing and pre-heating the femoral component on the mechanical properties of the cement mantle

“…3,[8][9][10] The extent of porosity within the cement mantle is influenced by different factors including the formulation of the cement, the method of mixing, the technique of injection and the surface properties of the implant. Great efforts have been made to optimise cement formulation, [11][12] to improve mixing and/or injection, 13-15 and to select the best texture for the surface of the implant. 16,17 Despite these efforts, some degree of porosity can still be observed in bone cement mantles.…”

Acrylic Bone Cements: The Role of Nanotechnology in Improving Osteointegration and Tunable Mechanical Properties

“…New iodine-containing bone cements showed increased fatigue resistance 96 and decreased thermal necrosis. 97 It was also proved that iodine-cement and BaSO 4 -cement showed analogous cytocompatibility throughout every in vitro experiments. 98 Despite Hernández et al 99 reported that acrylic bone cement containing 10% bismuth salicylate in the liquid phase had overall good properties (thermal, mechanical and rheological properties) and optimum homogeneity and radiopacity, nanotechnology is a more attractive alternative to obtain reinforced composite materials due to strong interfacial interactions between the nanostructured fillers and the polymer matrix.…”