Graphene is an excellent filler for the development of reinforced composites. This study evaluated bone cement composites of graphene oxide (GO) and poly(methyl methacrylate) (PMMA) based on the proliferation of human bone marrow mesenchymal stem cells (hBMSCs), and the anabolic and catabolic effects of the incorporation of GO on osteoblast cells at a genetic level. Surface wettability and roughness were also evaluated at different GO concentrations (GO1: 0.024 wt% and GO2: 0.048 wt%) in the polymer matrix. Fabricated specimens were tested to (a) observe cell proliferation and (b) identify the effectiveness of GO on the expression of bone morphogenic proteins. Early osteogenesis was observed based on the activity of alkaline phosphatase and the genetic expression of the run-related transcription factor 2. Moreover, bone strengthening was determined by examining the collagen type 1 alpha–1 gene. The surface roughness of the substrate material increased following the addition of GO fillers to the resin matrix. It was found that over a period of ten days, the proliferation of hBMSCs on GO2 was significantly higher compared to the control and GO1. Additionally, quantitative colorimetric mineralization of the extracellular matrix revealed greater calcium phosphate deposition by osteoblasts in GO2. Furthermore, alizarin red staining analysis at day 14 identified the presence of mineralization in the form of dark pigmentation in the central region of GO2. The modified GO–PMMA composite seems to be promising as a bone cement type for the enhancement of the biological activity of bone tissue.

This laboratory study set out to characterize Calcium Phosphate (CaP) based bone cements with added Zinc Oxide (ZnO) embedded in Poly (methyl methacrylate) (PMMA). Bone cements with varying percentages of CaP mixed with and without varying percentages of ZnO in PMMA were fabricated by one-step polymerization by reacting equimolar ratios of MMA powder and acrylic resin. Neat-PMMA was used as control throughout the experiment. Fabricated samples were tested for their contact angle measurement, surface roughness, nanohardness, elastic modulus, and also their chemical characterization using Fourier-transform infrared spectroscopy (FTIR) and Raman spectroscopy. A one-way analysis of variance (ANOVA) was used as a statistical method, and a p-value of less than 0.05 was considered statistically significant. It was found that increasing CaP content elevated the hydrophobicity of the composites while mechanical properties increased with the increase of CaP. On the contrary, the addition of ZnO did not show any significant effect. The optimal concentration was observed to be at 20% CaP loading where the mechanical properties were balanced with the hydrophilic nature of CaP. It was also noted that different wt.% of ZnO and CaP did not affect the physicochemical characteristics of the composites. The PMMA-CaP composites demonstrated encouraging results and necessitate further studies to ascertain the implementation of these bone cements clinically.

No abstract

No abstract