Three-dimensional bioprinting technologies and biomaterials for nerve guidance conduits: A review

Abstract

Repairing long peripheral nerve gap injuries and reconstructing corresponding functions remain two major challenges in regenerative medicine. The application of nerve conduits, constructed via neural tissue engineering (NTE) strategies, has emerged as a prominent research focus and an essential tool for nerve repair. Among NTE technologies, additive manufacturing (AM), especially bioprinting, represents one of the most promising fabrication approaches for neural conduits. This review systematically analyzes the current research progress on peripheral nerve conduit fabrication, particularly emphasizing how different conduit structures, biomaterials, and AM techniques synergistically influence nerve regeneration outcomes. The review also summarizes the principles and recommendations for selecting appropriate nerve conduit structures for different defect lengths and injury stages, providing a theoretical basis for the design and practical application of conduit structures. Additionally, it focuses on the role of advanced bioprinting technologies in enhancing conduit complexity, cell guidance, and functional recovery. Furthermore, this review highlights emerging trends and discusses critical future directions for integrating structure design, material selection, and printing strategies toward the next generation of nerve conduits. This review aims to provide a comprehensive perspective for advancing peripheral nerve repair by bridging biomaterial engineering, manufacturing innovations, and regenerative medicine needs.

Keywords

Additive manufacturing / Biofabrication / Nerve conduit / Neural tissue engineering

Funding

The research is funded by the Research Foundation Flanders (FWO) for the doctoral fellowship (1S47325N) granted to Yuexi Zhuang.

Conflict of interest

Eleonora Ferraris is an Editorial Board Member of this journal, but was not in any way involved in the editorial and peer-review process conducted for this paper, directly or indirectly. Separately, other authors declared that they have no known competing financial interests or personal relationships that could have influenced the work reported in this paper.

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