A comparison between two different biomaterials for treatment of tracheal defect in dogs

This study was designed to evaluate the healing process of tracheal cartilage defect after implantation of two different biomaterials in dogs. Eighteen adult dogs from both sexes were used. They were divided into 2 equal groups. A window shape defect of about 3cm x 2cm was induced in the cervical part of three adjacent tracheal rings with their annular ligaments. In group one, the defect was closed with a small strip of ear cartilage (auto graft) from the same animal, while in the second group, calf's pericardium scaffold (xeno graft) was used to close the defect. All the animals were clinically monitored postoperatively, while gross pathological changes and biopsy collections for all animals was performed at 15, 30, 60 postoperative days. No postoperative clinical complications were recorded and all were looking healthy and resuming food and water intake normally. The gross pathological results revealed rapid occlusion to the trachea especially in first group and animals survived without any respiratory complications. The histological features in both groups were represented by newly granulation tissue formation and hyaline cartilage regeneration. The new hyaline cartilage cells formation was showed faster in group 1 rather than group 2. In conclusion, both grafts can be used for closing a tracheal defect in dogs with the priority of ear cartilage implantation.