2023, Vol. 27 ›› Issue (7): 1089-1095

Regeneration of facial nerve injury repaired by biomaterial nerve conduits

Xu Cong1, 2, 3, Zhao He1, 2, 3, Sun Yan1, 2, 3   

Abstract: BACKGROUND: Autologous nerve transplantation is the first choice for repairing the damaged facial nerve and treating facial paralysis, but the donor nerve is limited and will cause certain damage to the donor site. Biomaterial catheter is an important branch of tissue engineering. It provides physical barrier and three-dimensional regeneration channel for the nerve by connecting the nerve broken end, and it is the most potential facial nerve repair method.
OBJECTIVE: To review the application progress of biomaterials used to repair facial nerve injury in recent years.
METHODS: “biomaterials, nerve conduits, facial nerve” were used as the Chinese and English search terms. Relevant articles were searched on CNKI and PubMed from inception to January 2022. According to the inclusion and exclusion criteria, 68 relevant articles were finally included.
RESULTS AND CONCLUSION: (1) At present, biological material nerve conduits used for facial nerve injury can be roughly divided into acellular materials and degradable materials. Acellular materials mainly include arteries, veins, and muscles, while degradable materials mainly include collagen, polyglycolic acid, polycaprolactone, silk protein, chitosan, and graphene. (2) Vein and collagen are the two materials most studied at present. After combining with stem cells and neurotrophic factors, their nerve regeneration effect is significantly enhanced, but there is still a certain gap between them and autologous nerve transplantation. (3) Graphene is more active and more easily combined with neurotrophic substances. It has anti-inflammatory effects and promotes the increase of M2 macrophages, which is conducive to nerve healing and regeneration. It is one of the most promising biomaterials at present. (4) The effects of various biomaterials loaded with stem cells, growth factors or sculpted micropatterns on the repair of facial nerve injury were summarized. “Multiple combination” is the trend of nerve conduit development. The combination of cells and growth factors can effectively promote nerve regeneration, but the difference of adsorption rate and release rate between biomaterials is large, which easily leads to resource waste and short action time. (5) The longitudinal microchannels carved on the nerve conduit can provide guidance for neuronal regeneration and speed up axon regeneration, which is the focus of future research on nerve conduit direction for facial nerve injury.
Key words: facial nerve, nerve conduit, biomaterial, nerve injury, multiple combination, stem cell, growth factor, longitudinal microchannel