Scanning Electron Microscopy Study of Di-Calcium Phosphate Dehydrate Coatings on Magnesium Substrates for Potential Use in Orthopaedic Implants

Author(s): Lennart Schaefer, Wisut Chamsa-ard, Derek Fawcett, Chun Che Fung, Gerrard Eddy Jai Poinern

Magnesium has attracted considerable medical interest due to its mechanical properties being similar to bone. In addition, magnesium is also biocompatible and biodegradable, which makes it an ideal candidate for biodegradable orthopaedic implants. However, magnesium’s high corrosion rate in body fluids makes it an unsuitable material for the manufacture of implants. The present study investigates a straightforward chemical immersion technique that deposits di-calcium phosphate dehydrate (DCPD) coatings onto magnesium substrates to increase their corrosion resistance to body simulated fluids like phosphate buffer saline solution and Ringer’s solution. Scanning electron microscopy revealed the coating structures and morphologies were characterised by flower-like surface feature that were resistant to both body simulated fluids. Thus, indicating the coatings could significantly reduce magnesium corrosion rates in the body environment.

Magnesium, Biodegradation, Protective Coating, Orthopaedic Implants

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