Chinese Journal of Tissue Engineering Research ›› 2019, Vol. 23 ›› Issue (2): 204-210.doi: 10.3969/j.issn.2095-4344.1508

Previous Articles     Next Articles

Preparation and characterization of novel porous polymethyl methacrylate bone cements

Gao Shan1, Zhou Fang1, Lü Yang1, Yuan Liang1, Li Ailing2, Qiu Dong2   

  1. 1Department of Orthopedics, Peking University Third Hospital, Beijing 100191, China; 2Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
  • Received:2018-09-26 Online:2019-01-18 Published:2019-01-18
  • Contact: Zhou Fang, Chief physician, Professor, Department of Orthopedics, Peking University Third Hospital, Beijing 100191, China
  • About author:Gao Shan, Doctorate candidate, Department of Orthopedics, Peking University Third Hospital, Beijing 100191, China
  • Supported by:

    the National Natural Science Foundation of China, No. 51473004 (to ZF)

PDF

228

Abstract:

BACKGROUND: Porous tricalcium phosphate/polymethyl methacrylate bone cement can overcome the poor osteoconduction of traditional polymethyl methacrylate bone cement. But the addition of porogens may cause a significant reduction in the mechanical properties of composite bone cements.

OBJECTIVE: To improve the mechanical properties of porous tricalcium phosphate/polymethyl methacrylate at different proportions, and to observe the mechanical properties, agglomeration, porosity and biosafety of composite bone cements.
METHODS: Different groups of composite bone cements were prepared by adding different contents of tricalcium phosphate (40%, 50%, 60%) in solid phase and hydroxyethyl methylacrylate (0%, 5%, 10%, 15%, 20%) in liquid phase. The compressive strength, bending strength, maximum setting temperature, and setting time were measured, and screened the optimal ratio preliminarily. Then the pore formation properties of the optimal specimens were observed by scanning electron microscopy at 12 weeks after soaking in simulated body fluid. The osteogenic precursor cells were co-cultured with the preferred composite bone cement extract for 24 hours. The absorbance was then measured by cell counting kit-8 assay, and the cell viability was calculated.
RESULTS AND CONCLUSION: The compressive strength of composite bone cement was increased when adding 40% and 50% of tricalcium phosphate in solid phase, but decreased when tricalcium phosphate concentration reached 60%. The bending strength was significantly decreased after adding tricalcium phosphate, showing a linear relationship. Addition of hydroxyethyl methylacrylate in liquid phase could strengthen the compressive strength and bending strength of composite bone cements, but no longer enhanced the mechanical properties when the concentration exceeded 15%. The maximum setting temperature of the composite bone cement was about 80 oC, regardless of the contents of tricalcium phosphate and hydroxyethyl methylacrylate. The setting time prolonged with the increasing of tricalcium phosphate and shortened with the increasing of hydroxyethyl methylacrylate. The formulas containing 50% tricalcium phosphate in the solid phase and 0%, 5% and 10% hydroxyethyl methylacrylate, respectively in liquid phase were chosen as preferable groups. After immersing in the simulated body fluid for 12 weeks, there was porous structure whose pore size was approximately 100 μm formed on the surface of composite bone cement. The cell viabilities of the preferable composite bone cement extract were all more than 75%, showing there was no cytotoxicity. In conclusion, the addition of 50% tricalcium phosphate in solid phase and 10% hydroxyethyl methylacrylate A in liquid phase into polymethyl methacrylate from the optimal composite bone cement formulation. 

Key words: Polymethacrylic Acids, Calcium Phosphates, Bone Cements, Tissue Engineering

CLC Number: