Investigation on dimensional accuracy, compressive strength and measured porosity of additively manufactured calcium sulphate porous bone scaffolds

ABSTRACT

Additive manufacturing (AM), assisted by modern design tools, has recently shown a great potential for fabricating synthetic bone scaffolds. AM offers better control over structural features of porous scaffolds at the time of fabrication. In this study, calcium sulphate-based porous bone scaffolds have been fabricated using 3D printing technology. Initially, the minimum pore size (600 µm) that can be de-powdered is identified through a pilot study. Then, four porous scaffolds (VJ_P6_S6, VJ_P6_S7, VJ_P7_S6 and VJ_P7_S7) have been designed using two different pore and strut sizes (600 and 700 µm) and fabricated along x-, y- and z-axes on ZPrinter® 450. The fabricated scaffolds are then compared for dimensional accuracy, compressive strength and measured porosity. Results show that scaffolds fabricated along the x-axis are found best in terms of dimensional accuracy, compressive strength and fabricated porosity. The maximum compressive strength among solid samples is found 2.92 MPa; whereas, for porous samples, it is found 1.86 MPa in VJ_P7_S6 sample fabricated along the x-axis. The porosity in fabricated samples is measured using micro-computed tomography scan images and found a minimum reduction of 3.9% from the designed porosity in sample VJ_P7_S7 fabricated along the x-axis. A preliminary biological investigation reveals that the used material has no significant toxic effect on cells and provides a favourable media for cell adhesion and growth.

KEYWORDS:

• 3D printing
• additive manufacturing
• calcium sulphate
• compressive strength
• computed tomography
• porous bone scaffold

Acknowledgements

The authors are thankful to Dr Ashish Agrawal and Dr P. Ganesh of RRCAT, Indore, for the help and support extended during CT scan, XRD and compressive strength testing of the samples.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work is financially supported by the Madhya Pradesh Council of Science and Technology (MPCST), Bhopal, India, vide sanction letter No. 3965/CST/R&D/Phy&Engg/2017-18, dated 31/03/2018.