Effect of triphenyl bismuth on glass transition temperature and residual monomer content of acrylic bone cements

Abstract

Self-curing acrylic bone cements are widely used in the fixation of prosthetic implants in orthopaedic surgery. Commercial bone cements are rendered radiopaque by the addition of heavy metal salts of barium and zirconia. The addition of barium sulphate adversely affects the mechanical strength and fracture toughness of bone cement and despite the fact that it has low solubility in water; its slow release and subsequent toxicity have caused concern. In an earlier study triphenyl bismuth (TPB) was found to be a viable alternative as a radiopaque agent in acrylic bone cements, which provided enhanced homogeneity. In this study we report the effect of the inclusion of TPB on the thermal properties of PMMA-based bone cements using both conventional DSC and Modulated Temperature DSC. Furthermore, analysis of the residual monomer contents is reported analysed by NMR spectroscopy in order to ascertain the influence of TPB on the polymerisation reaction. The glass transition temperature (Tg) determined by DSC showed that the values decreased with the addition of increasing amounts of TPB through both blending and dissolution methods; however, the method of incorporating TPB did not influence Tg. The magnitude of reduction was dependent of the amount of TPB and was greatest in the case of highest concentration of TPB used. A TPB melting peak was observed in the 25 wt% TPBBC, suggesting a limit to the solubility of TPB. The residual monomer analysis showed that at 10 and 15% by weight of TPB in the cement caused no significant changes in the residual monomer content but 25 wt% of TPB exhibited a significantly higher residual monomer content.

A Novel Water‐Soluble Hexanuclear Bismuth Oxido Cluster – Synthesis, Structure and Complexation with Polyacrylate

“…In addition to their almost non-toxic behavior, bismuth-containing materials show high radiopacity, and thus some of them are investigated as potential X-ray imaging agents for computed tomography (CT) and as X-ray contrast additives in bone and dental cements, for example, to enable postoperative examination of their anchorage, texture, and form fit. [7,8] Conventional radio contrast media like barium sulfate or zirconium dioxide can cause a greater osteolytically induced loss than bismuthcontaining cements. [8,9] Furthermore, the addition of barium sulfate causes an incompatibility between the metal salt and the polymer, hence the mechanical strength and fracture toughness of the bone cement is affected.…”

“…[7,8] Conventional radio contrast media like barium sulfate or zirconium dioxide can cause a greater osteolytically induced loss than bismuthcontaining cements. [8,9] Furthermore, the addition of barium sulfate causes an incompatibility between the metal salt and the polymer, hence the mechanical strength and fracture toughness of the bone cement is affected. [8] Other radiopaque bismuth-containing fillers such as Bi(NO 3 ) 3 , BiBr 3 , Bi 2 O 2 (CO 3 ), and Bi 2 O 3 were suggested, and their use was patented.…”

“…[8,9] Furthermore, the addition of barium sulfate causes an incompatibility between the metal salt and the polymer, hence the mechanical strength and fracture toughness of the bone cement is affected. [8] Other radiopaque bismuth-containing fillers such as Bi(NO 3 ) 3 , BiBr 3 , Bi 2 O 2 (CO 3 ), and Bi 2 O 3 were suggested, and their use was patented. [10,11] A major disadvantage associated with the low solubility of these inorganic bismuth compounds is phase separation due to their incompatibility with the organic matrix.…”

“…[11] BiPh 3 was mentioned in the literature as another promising X-ray contrast additive in PMMA-based bone cements. [8,9,11] This organobismuth compound is hydrophobic and possesses antimicrobial, fungicidal, and antioxidant properties, but its application in dental and bone cements holds the danger of the formation of toxic thermal and photochemical decomposition products. [8] We have been interested in bismuth oxido clusters as molecular precursors to materials based on bismuth oxide for several years now.…”

Effect of iodixanol particle size on the mechanical properties of a PMMA based bone cement

“…The closed pan was weighed and then inserted into the DSC (DSC Q1000, TA Instruments, New Castle, USA), respectively. The analysis consisted of the cycles heating -cooling -heating; these were done at 10 ºC min -1 between 10 ºC and 150 ºC following [12][13][14]. The data was analysed using Universal Analysis 2000 (TA Instruments, New Castle, USA), and the glass transition temperature T g calculated by the software on the second heating cycle.…”