Wound healing in the jugal mucosa of rats with a cold blade scalpel and an ultrasonic harmonic scalpel

Abstract

Ultrasound harmonic scalpel has been recently introduced in otorhinolaryngological procedures. Aim: to assess macro and microscopic evolution of the healing process of wounds created in the jugal mucosa of rats by the use of ultrasound scalpel. Method: we used 30 Wistar rats in which we made mucosal incisions on the right jugal mucosa with the ultrasound harmonic scalpel (USHS) and on the left side with the cold blade scalpel (CBS). Macroscopic and microscopic evaluations were carried out on the third, seventh and fourteenth days of postoperative. For the microscopic evaluation we used HE to asses the inflammatory process and the Sirius Red approach for collagens type I and III. Anti-CD 3 antibodies and anti-factor VIII assessed the concentration of T-lymphocytes and neovessels. Results: the USHS caused greater cell damage with reepitelization delay. Microscopy showed more intense inflammatory reactions and a loss in collagen build up, delay in scar maturation and a greater vessel neoformation. Conclusion: USHS brings about a greater lesion in the incision area; delayed regeneration; promotes greater inflammatory process and angiogenic activity; delays in fibroplasia and scar tissue maturation on the rats' jugal mucosa when compared to cold blade scalpel. © Revista Brasileira de Otorrinolaringologia.