Integrated three-dimensional fiber/hydrogel biphasic scaffolds for periodontal bone tissue engineering

Combining a tissue engineering scaffold made of a load-bearing polymer with a hydrogel represents a powerful approach to enhancing the functionalities of the resulting biphasic construct, such as its mechanical properties or ability to support cellular colonization. This research activity was aimed at the development of biphasic scaffolds through the combination of an additively manufactured poly(epsilon-caprolactone) (PCL) fiber construct and a chitosan/poly(gamma-glutamic acid) polyelectrolyte complex hydrogel. By investigating a set of layered structures made of PCL or PCL/hydroxyapatite composite, biphasic scaffold prototypes with good integration of the two phases at the macroscale andmicroscale were developed. The biphasic constructs were able to absorb cell culturemedium up to 10-fold of their weight, and the combination of the two phases had a significant influence on compressive mechanical properties compared with hydrogel or PCL scaffold alone. In addition, due to the presence of chitosan in the hydrogel phase, biphasic scaffolds exerted a broad-spectrum antibacterial activity. The developed biphasic systems appear well suited for application in periodontal bone regenerative approaches in which a biodegradable porous structure providing mechanical stability and a hydrogel phase functioning as absorbing depot of endogenous proteins are simultaneously required. (C) 2016 Society of Chemical Industry