Fig. 1.

Schematic illustration of the preparation and application in guiding directional bone growth of the 3D-printed CL scaffolds inspired by the features of natural conches. The biomimetic scaffolds were comprised of spiral sections and cavities, as well as intermediate support spar and peripheral wall with through macropores. Benefiting from the spiral biomimetic structure, the CL scaffolds greatly enhanced cell behaviors including adhesion, proliferation, osteogenic differentiation, and significantly promoted cell migration from the bottom to the top of the scaffolds, which was like “cells climbing stairs”. Furthermore, the CL scaffolds well guided the bottom-up directional bone growth in vivo, similar to the growth process of natural conches.