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Background: Peripheral nerve trauma results in functional loss in the innervated organ. Recovery without surgical intervention is seldom successful. Many surgical techniques can be used for repair in experimental models. Objective:The authors investigated the source and delivery method of stem cells, their outcomes, and whether stem cells will be differentiated in the injured nerve and whether they improve the regenerative process. Materials and Methods:The following key terms were used: nervous regeneration, nerve regeneration, facial nerve regeneration, stem cells, embryonic stem cells, fetal stem cells, adult stem cells, peripheral nerve, peripheral nerve trauma, and peripheral nerve traumatism. The inclusion criteria were the experimental studies that applied stem cell therapy and tissue engineering for nerve repair.Results: Out of 197 studies, 52 studies meeting the inclusion criteria were reviewed. Different sources of stem and precursor cells were noticed (bone marrow mesenchymal stem cells, adipose-derived stem cells, dental pulp cells, umbilical cord, and neural stem cells) for their potential application in the patients with peripheral nerve injuries. Different material conduits (vases, collagen, and polyglycolic acid) were used as bridges between the two nerve endings. Immunochemistry and electrophysiology were used for analyzing regenerative effects. Although recent studies have shown that stem cells can act as a promising bridge for nerve repair, considerable optimization of these therapies will be required for their usage in a clinical setting. Conclusion:The use of stem cells derived from different sources presents promising results for nerve regeneration and effective neural and functional results. The best choices are BMSC and ADSC. The use of conduit also help and maximize the nerve repair, and in this way induce better myelination and axonal growth of peripheral nerves.

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