| The tissue engineering of hard organs and tissues containing cartilage, teeth, and bones is a widely used and
rapidly progressing feld. One of the main features of hard organs and tissues is the mineralization of their
extracellular matrices (ECM) to enable them to withstand pressure and weight. Recently, a variety of printing
strategies have been developed to facilitate hard organ and tissue regeneration. Fundamentals in threedimensional (3D) printing techniques are rapid prototyping, additive manufacturing, and layered built-up and
solid-free construction. This strategy promises to replicate the multifaceted architecture of natural tissues.
Nowadays, 3D bioprinting techniques have proved their potential applications in tissue engineering to construct
transplantable hard organs/tissues including bone and cartilage. Though, 3D bioprinting methods still have some
uncertainties to fabricate 3D hard organs/tissues. In the present review, most advanced technical improvements,
experiments, and future outlooks of hard tissue engineering are discussed, as well as their relevant additive
manufacturing techniques. |