Bioactive poly(methyl methacrylate) for bone fixation

Abstract

Poly(methyl methacrylate) (PMMA) is broadly used for bone fixation. One of the major concerns of using this polymer is the lack of post-implantation integration with the host tissue. We have produced a novel hybrid ceramic-thermoplastic composite manufactured by a sol-gel method via covalent bonding between bioactive glass and PMMA to address this shortcoming. The uniform distribution of bioactive glass promoted the bioactivity of PMMA and substantially improved the biological properties. In this paper, we describe a refinement of the synthesis process of a previously manufactured PMMA-bioactive glass hybrid resulting in significantly more rapid fabrication. Key innovations were the replacement of tetrahydrofuran with ethanol as a more biologically benign reaction solvent, and the addition of sodium bicarbonate as a non-toxic catalyst. Our results showed that the gelation time was decreased 100-fold by increasing the reaction temperature from 25 C to 70 C, which also increased the rate of hardening 7-fold. The resulting hybrid monoliths displayed a more condensed structure with an 80% increase in network connectivity and 6-fold more resistance to degradation. These favorable biophysical properties of the new class of hybrids also enhanced the osteoblast adhesion and proliferation compared with the previously developed hybrids. This bioactive glass-PMMA hybrid has great potential to be used as a bone filler.

Tailoring Mechanical Properties of Sol–Gel Hybrids for Bone Regeneration through Polymer Structure

“…Polymethacrylate can be copolymerized with methyl methacrylate (MMA) and 3-(trimethoxysilyl)­propyl methacrylate (TMSPMA) to produce an alkoxysilane containing polymer. Hybrids of poly­(MMA- co -TMSPMA) with a conetwork of SiO 2 have been investigated as biomaterials due to promising mechanical properties and bioactivity. − However, the studies were more focused on macroscopic properties of the hybrids. The only variable investigated for the organic source was the TMSPMA content within the copolymers.…”

Novel Organic–Inorganic Nanocomposite Hybrids Based on Bioactive Glass Nanoparticles and Their Enhanced Osteoinductive Properties

“…However, overcoming the brittleness issues of BGs [9,[14][15][16][17][18][19][20][21][22] comes at the cost of a significantly lower bioactivity compared with pure BGs [4,23]. For instance, the immersion of gelatin-siloxane or chitosan-siloxane hybrids in simulated body fluid (SBF) did not produce bone-like apatite formation on the hybrid surface for three weeks [19,24]. Similarly, existing hybrid materials only modestly stimulate the expression of osteogenicrelated gene markers such as phosphatase alkaline (ALP) activity [20].…”

Fabrication and investigation of high-quality glass-ceramic (GC)–polymethyl methacrylate (PMMA) composite for regenerative medicine

“…19 Furthermore, Chen et al demonstrated enhanced bioactivity of silicate bioceramic-PMMA composite compare to that of neat PMMA, 15 while results obtained by Ravarian et al showed that PMMA-bioactive glass composite supports osteoblast growth and differentiation. 20 Currently, a research trend is to fabricate scaffolds from bioceramic and polymer component with architectures mimicking the three-dimensional interconnected porosity of natural bone and an ability to guide cellular attachment and promote bone growth is one of the critical issues. 21 Here we present the synthesis of glass-ceramic (GC) powders and fabrication of GC-PMMA composite via polymerization induced by photoionization process.…”