Dual-Curing Polylactide for Resorbable Bone Cement

Abstract:

Polymeric cement based on poly (methyl methacrylate) (PMMA) has been known as a common material for fixation of prostheses with the advantages of mechanical properties. However, one of drawbacks of PMMA cement is heat produced during polymerization. The elevating temperature during polymerization resulting from exothermic polymerization of MMA can cause bone cellular necrosis. Additionally, the residual MMA monomer after polymerization is an issue regarding the biocompatibility of cement. In this study, a resorbable cement based on polylactide (PLA) has been developed. Its physical, mechanical and biological properties were investigated as an alternative biocompatible bone cement. The dual-cured polylactide cements prepared by combining spherical powder of star-shaped and linear PLA blends with triethylene glycol dimethacrylate liquid were radically polymerized by UV-VIS light and self-curing methods. Flexural strength, maximum temperature during polymerization and biocompatibility via the percentages of cell viability using MTT assay of the dual-cured polylactide were determined to meet requirements for bone cement. The best flexural strength of 108 MPa was achieved from the cement composed of 80%-wt of star-shaped PLA with molecular weight (Mw) of 10770. The preparation of cement using paste/liquid mixing, in which the powder was allowed to wet in the liquid before mixing, significantly encouraged mechanical properties compared to powder/liquid mixing due to satisfactory solubility of PLA prior to polymerization. The amount of initiator/activator was studied to fine-tune the maximum temperature during polymerization. The maximum temperature during polymerization of the PLA cement was in the range of 80-90 degree Celsius and the percentage of osteogenic cell viability immediately after cement setting was 83 indicating a non-toxic material. Therefore, this PLA cement polymerized with a dual curing mode is promising for a resorbable bone cement.

• Periodical: Key Engineering Materials (Volume 798)
• Pages: 77-82
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.798.77
• Online since: April 2019
• Authors: Somruethai Channasanon*, Pakkanun Kaewkong, Siriporn Tanodekaew
• Keywords: Polylactide Cement, Resorbable Bone Cement

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