Optimum spacer removal and sintering temperature for porous magnesium scaffold fabrication

Document Type: Original Article


1 Department of materials science and engineering, Golpayegan University of Technology

2 Dental Research Center, School of Dentistry, Isfahan University of Medical Sciences, Isfahan 81746-73461, Iran



Porous magnesium scaffolds have been of interest to tissue engineering researchers because of their biodegradability and biocompatibility. Space holder method is a simple method for fabrication these scaffolds, but suffer from clean spacer agent removal process. This study was conducted to introduce a modified dissolution method (Distilled water+HF acid) for the carbamide (as spacer agent) removal from inside the magnesium scaffold. Also the effect of the sintering temperature on mechanical and structural characteristics were studied by the compression test and the optical and Scanning Electron Microscopes (OM and SEM). In addition, effect on phases present in scaffold after sintering was investigated using x-ray diffraction (XRD) analysis. The results showed that the HF 48% solution is superior to that of previously used solutions (water, ethanol and sodium hydroxide) for carbamide removal, including more carbamide removal efficiency (96±2%), and partial formation of MgF2 phase on the surface of magnesium scaffold. Also, raising the sintering temperature led to the increase of the scaffold shrinkage and the improvement of its mechanical characteristics.

Graphical Abstract

Optimum spacer removal and sintering temperature for porous magnesium scaffold fabrication


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