Delayed repair of the facial nerve and its negative impacts on nerve and muscle regeneration

Autor(es)

Cleuber Rodrigo de Souza Bueno ; Daniela Vieira Buchaim ; Benedito Barraviera ; Rui Seabra Ferreira Jr. ; Paulo Sérgio da Silva Santos ^[5] ; Carlos Henrique Bertoni Reis ; Marcelo Augusto Cini ^[7] ; Milton Carlos Kuga ^[8] ; Geraldo Marco Rosa Junior ^[9] ; Rogerio Leone Buchaim

• Tipo de documento: Artigo Científico
• Fonte: Journal of Venomous Animals and Toxins including Tropical Diseases; v. 30, 2024-05-27.

Resumo

Abstract Background: In this experimental protocol, we evaluated the immediate and delayed repair of the buccal branch of the facial nerve (BBFN) with heterologous fibrin biopolymer (HFB) as a coaptation medium and the use of photobiomodulation (PBM), performing functional and histomorphometric analysis of the BBFN and perioral muscles. Methods: Twenty-eight rats were divided into eight groups using the BBFN bilaterally (the left nerve was used for PBM), namely: G1 - control group, right BBFN (without injury); G2 - control group, left BBFN (without injury + PBM); G3 - Denervated right BBFN (neurotmesis); G4 - Denervated left BBFN (neurotmesis + PBM); G5 - Immediate repair of right BBFN (neurotmesis + HFB); G6 - Immediate repair of left BBFN (neurotmesis + HFB + PBM); G7 - Delayed repair of right BBFN (neurotmesis + HFB); G8 - Delayed repair of left BBFN (neurotmesis + HFB + PBM). Delayed repair occurred after two weeks of denervation. All animals were sacrificed after six weeks postoperatively. Results: In the parameters of the BBFN, we observed inferior results in the groups with delayed repair, in relation to the groups with immediate repair, with a significant difference (p < 0.05) in the diameter of the nerve fiber, the axon, and the thickness of the myelin sheath of the group with immediate repair with PBM compared to the other experimental groups. In measuring the muscle fiber area, groups G7 (826.4 ± 69.90) and G8 (836.7 ± 96.44) were similar to G5 (882.8 ± 70.51). In the functional analysis, the G7 (4.10 ± 0.07) and G8 (4.12 ± 0.08) groups presented normal parameters. Conclusion: We demonstrated that delayed repair of BBFN is possible with HFB, but with worse results compared to immediate repair, and that PBM has a positive influence on nerve regeneration results in immediate repair. (AU)

• Processo FAPESP: 21/11936-3 - Centro de Ciência Translacional e Desenvolvimento de Biofármacos
• Beneficiário: Benedito Barraviera
• Modalidade de apoio: Auxílio à Pesquisa - Centros de Ciência para o Desenvolvimento