A novel high-viscosity, two-solution acrylic bone cement: Effect of chemical composition on properties

Abstract

Solutions of poly(methyl methacrylate) (PMMA) powder predissolved in methyl methacrylate (MMA) have been developed as an alternative to current powder/liquid bone cements. They utilize the same addition polymerization chemistry as commercial cements, but in mixing and delivering via a closed system, porosity is eliminated and the dependence of material properties on the surgical technique is decreased. Twelve different sets of compositions were prepared, with two solutions of constant polymer-to-monomer ratio (80 g of PMMA/100 mL of MMA) and all combinations of four benzoyl peroxide (BPO) initiator levels added to the first solution and three N, N-dimethyl-p-toluidine (DMPT) activator levels added to the second. These compositions were tested, along with Simplex-P bone cement, for effects of BPO and DMPT concentrations on polymerization exotherm, setting time, flexural strength, modulus, and maximum strain. The results show that each of these dependent variables was affected significantly by the individual concentrations of BPO and DMPT and their interactions. The flexural strength, modulus, and polymerization exotherm reached their maximums at about a 1:1 molar ratio of BPO to DMPT. Most compositions had exotherms, setting times, and maximum strains within the range of commercial cements and flexural strengths and moduli up to 54 and 43% higher than Simplex-P, respectively.

Two novel high performing composite PMMA-CaP cements for vertebroplasty: An ex vivo animal study

“…In summary, the composite cements were prepared at powder-to-liquid ratios of 1.65:1, and had equal concentrations of PMMA and their respective fillers, with Zirconium dioxide (ZrO 2 ) as the radiopacifier. The cements contain a fixed concentration of initiator BPO and accelerator DMPT, 1.25% w/v and 0.7% v/v, respectively (w/v referring to the percent amount of the compound in relation to the PMMA weight or MMA volume) Allen et al, 2006;Hasenwinkel et al, 1999;Rodrigues et al, 2011). The two composite cements in this study were chosen, after a series of tests on different formulations, as the best suited for use in spinal augmentation .…”

A theoretical and experimental analysis of polymerization shrinkage of bone cement: A potential major source of porosity

“…(2)]. Table I shows the constituents and their volumes and masses for three different bone cements (i.e., Endurance™, Depuy Orthopedics; Simplex-P™, Stryker Howmedica, and a two-solution experimental bone cement 7,8 ). Equation (2) shows the determination of the effective density.…”

Characterization of a new composite PMMA-HA/Brushite bone cement for spinal augmentation

“…23,24,31,32 Briefly, the two-solution cement is a premixed system where all the components that make up the cement are mixed, swollen, and stored in a two-barrel cartridge (Sulzer MIXPAC, Ellsworth Adhesives, Germantown, WI). This system is advantageous because the cement is ready for use and can be mixed and dispensed on demand by using disposable static mixing elements (12 elements/6 mm, Ellsworth Adhesives, Germantown, WI).…”