Characterization of a new composite PMMA-HA/Brushite bone cement for spinal augmentation. (November 2014)

• Record Type: Journal Article
• Authors: Aghyarian, Shant; Rodriguez, Lucas C; Chari, Jonathan; Bentley, Elizabeth; Kosmopoulos, Victor; Lieberman, Isador H; Rodrigues, Danieli C
• Is Part Of: Journal of biomaterials applications. Volume 29:Number 5(2015:Jan.)
• Page Start: 688
• Page End: 698
• Publication Date: 2014-11
• Subjects: Composite bone cement -- vertebroplasty -- spine -- calcium phosphate -- vertebral compression fracture -- bone cement -- poly-methyl methacrylate; Biomedical engineering -- Periodicals; Biomedical materials -- Periodicals; 610.28
• DOI: 10.1177/0885328214544770
• Languages: English
• ISSNs: 0885-3282

Abstract

Calcium phosphate fillers have been shown to increase cement osteoconductivity, but have caused drawbacks in cement properties. Hydroxyapatite and Brushite were introduced in an acrylic two-solution cement at varying concentrations. Novel composite bone cements were developed and characterized using rheology, injectability, and mechanical tests. It was hypothesized that the ample swelling time allowed by the premixed two-solution cement would enable thorough dispersion of the additives in the solutions, resulting in no detrimental effects after polymerization. The addition of Hydroxyapatite and Brushite both caused an increase in cement viscosity; however, these cements exhibited high shear-thinning, which facilitated injection. In gel point studies, the composite cements showed no detectable change in gel point time compared to an all-acrylic control cement. Hydroxyapatite and Brushite composite cements were observed to have high mechanical strengths even at high loads of calcium phosphate fillers. These cements showed an average compressive strength of 85 MPa and flexural strength of 65 MPa. A calcium phosphate-containing cement exhibiting a combination of high viscosity, pseudoplasticity and high mechanical strength can provide the essential bioactivity factor for osseointegration without sacrificing load-bearing capability.