Comparison of a new bisphenol-a-glycidyl dimethacrylate-based cortical bone void filler with polymethyl methacrylate

Abstract

IntroductionBisphenol-a-glycidyl dimethacrylate (bis-GMA) resins have been studied in orthopedic applications since the late 1970s [21]. Various formulations were developed in efforts to reduce the amount of leachable unreacted monomer, to avoid high local temperatures during polymerization, to improve mechanical properties, and to enhance direct bone contact [4,19]. Current formulations of bis-GMA resins have achieved these goals of improved mechanical, chemical, and biologic properties [14,18]. One such formulation is Cortoss synthetic cortical bone void filler, a biocompatible, bone-bonding, terpolymer cortical bone substitute containing bisphenol-a-glycidyl dimethacrylate (bis-GMA), bisphenol-a-ethoxy dimethacrylate (bis-EMA), and triethylene glycol dimethacrylate (TEGDMA) resins reinforced with synthetic combeite glass-ceramic particles to stimulate bone apposition at the interface, barium boroaluminosilicate glass for radiopacity and strength, and silica for improved viscosity.For more than 20 years, polymethyl methacrylate (PMMA) bone cement has been used to reconstruct vertebral bodies that have collapsed as a result of trauma or tumor invasion [8,9,12]. Long-term studies report that these treatments are highly durable and that significant failAbstract A newly formulated and reinforced bisphenol-a-glycidyl dimethacrylate (bis-GMA) resin (Cortoss/Orthovita, Malvern, Pa.) was compared with Simplex P polymethyl methacrylate (Stryker Howmedica Osteonics, East Rutherford, N.J.) in rabbits for up to 52 weeks and in sheep for up to 78 weeks. As seen in scanning electron microscopy and histology examinations, both implant materials were surrounded by bone at late time periods, with fibrous layers of connective tissue seen in half the Simplex P specimens. No clinically significant safety differences between implant materials were apparent. Interfacial bond strengths between the implant and bone generally increased with time, but were 4.5-fold greater with Cortoss than Simplex P at 24 weeks, and 100-fold greater at 52 weeks. Forces required to displace 316SS rods held in place with Cortoss were consistently greater than forces to displace rods held in place with Simplex P. No statistically significant differences in displacement forces were found between rods held in place with Cortoss polymerized in situ and rods held with prepolymerized Cortoss. Interfacial bond strengths were greater for Simplex P that was polymerized in situ than for prepolymerized polymethyl methacrylate specimens. Cortoss synthetic cortical bone void filler is a good candidate material to fix implants in bone. It has characteristics consistent with longterm safety and has a better ability to bond to bone than Simplex P.

Fresh cortical autograft versus fresh cortical allograft effects on experimental bone healing in rabbits: radiological, Histopathological and Biomechanical evaluation

“…Autogenous bone graft is commonly used and is the standard to which allografts and graft substitute are compared (Fox 1984;Alexander 1985Alexander , 1987Brinker et al 1997;Fitch et al 1997;McLaughlin and Roush 1998). Allografts are considered to be highly osteoconductive (Lind and Bunger 2001), weakly osteoinductive and nonosteogenic (Marchesi 2000;Erbe et al 2001). Therefore, bone formation rates in allogenic grafting can be expected to be inferior to that of autologous bones.…”

Injectable Bone Cements for Spinal Column Augmentation: Materials for Kyphoplasty/Vertebroplasty

“…106 Other promising cement compositions include glass-ceramic-based cements. 52,107 The studies described in this section cover just a small selection of several biomaterials currently under study, but it can be expected that many more new biomaterials will be designed, tested and eventually qualify for clinical investigation in the near future. The prospect of the availability of biomaterials better adapted to 109 The same year a review was published, in which it was emphasized that this technique should be reserved for carefully selected patients who do not respond to conservative treatment.…”

“…51 Alternative acrylic cement compositions, such as dimethacrylate-based cements, have been designed showing favorable biomechanical and biocompatible properties compared to regular PMMA cements. 52 Currently, most of these biomaterials continue to be studied in a meticulous way. Recent data suggest that the principles underlying their formulation may lead to enhanced clinical performance.…”

Current status of percutaneous vertebroplasty and percutaneous kyphoplasty – a review

“…Bioactive glass beads or glass ceramic powder when added to the organic matrix containing bisphenolA-glycidyl methacrylate (Bis GMA) and PMMA resulted into new bone formation around the beads [46,47]. Cortoss, a composed material-based bone cement currently undergoing clinical trials for vertebroplasty and kyphoplasty is composed of terpolymer resin with combeite glass-ceramics [48,49]. Strontium is radiopaque and it has also been shown to induce new bone formation and to inhibit bone resorption in vitro and in vivo [50–53].…”