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

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 mu m) that can be de-powdered is identified through a pilot study. Then, four porous scaffolds (VJ_P6_S6, VJ_P6_S7, VJ_P7_S6andVJ_P7_S7) have been designed using two different pore and strut sizes (600 and 700 mu m) and fabricated along x-, y- and z-axes on ZPrinter (R) 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 inVJ_P7_S6sample 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 sampleVJ_P7_S7fabricated 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.

Automated summary

Additive manufacturing technology has been successfully used to fabricate calcium sulphate-based porous bone scaffolds with good dimensional accuracy and compressive strength when fabricated along the x-axis. The fabricated scaffolds showed consistent porosity with the designed values and were found to have no significant toxic effects on cells, providing a favorable environment for cell adhesion and growth.