Polylactide scaffold fabrication using a novel combination technique of fused deposition modeling and batch foaming: dimensional accuracy and structural properties

Abstract

A combination technique of fused deposition modeling (FDM) and batch foaming is introduced as a novel technique to fabricate tissue-engineered scaffolds. Three scenarios are implemented to fabricate porous scaffolds for tissue engineering applications. The dimensional accuracy, porosity, and pore size of samples are compared in three scenarios. The first scenario includes solid samples produced by FDM 3D printing at different infill percentages. The findings revealed that the porosity of solid FDM samples can be controlled by adjusting the infill percentage. However, the real porosity was smaller than the nominal porosity. The results indicated that the solid FDM samples had lower dimensional accuracy compared to solid injected samples. The second scenario consists of foamed injected samples, injection-molded samples foamed by batch foaming technique, at different injection pressures. The results showed that a bimodal pore structure containing big pores in the fine range and small pores in the micro range were achieved. The third scenario contains foamed FDM samples, FDM samples foamed using a batch foaming technique. The findings disclosed that the foamed FDM samples had higher dimensional accuracy than the foamed injected samples. Also, the foaming significantly improved the porosity of FDM samples, for instance by 43% at infill percentage of 80%. The FDM/batch foaming combination technology can produce porous tissue-engineered scaffolds with simultaneously macro and micropores, desirable porosity, and excellent dimensional accuracy. This technique has a bright outlook for future scaffolds applications.