Development of tracheal prostheses made of porous titanium: a study on sheep

Abstract

Authors report the development of a biomaterial to be used for tracheal and laryngeal reconstruction. This experimentation follows the replacement of trachea in rats with porous titanium implants. The aim of the study is to test this type of prosthesis on sheep, whose trachea is of comparable size to that of humans. Six ewes were implanted with porous titanium implants after resection of 5 cm of trachea. The planned period for the implantation was from 3 to 6 months before the sacrifice of the animals for histological analysis. After a simple immediate postoperative course, the implantations developed complications of tracheal patency, responsible for four deaths (tracheal obstruction by mucous plug n = 2, inferior necrosis of trachea n = 1, pneumopathy n = 1). The two remaining sheep presented no complications. The mechanical performance of the prostheses was good. The histological results showed an inflammatory stenosis of the tracheo-prosthetic junctions, which was not the direct result of death. The protheses were integrated by the surrounding tissue, but endoprosthetic colonisation by pseudostratified ciliated columnar epithelium was low or nil. The absence of endoprosthetic lining was responsible for the complications. The biocompatibility of the biomaterial is not in question, but the surgical procedure will have to be modified by an endoprosthetic mucous graft before implantation so as to accelerate healing process.

Model of extensive and severe tracheal stenosis in dogs

“…10 It is also necessary a complementary study to establish the relations 17 between the extension/numbers of rings and the extension/grade of induced stenosis. Functional study must be performed to clarify the possible mechanism of wheeze generation 22 in this realistic tracheostenosis model.…”

“…[4][5][6][7] However, in cases of extensive longitudinal stenosis a tracheotomy below to the stricture area could be necessary and the stenosis treated with orthesis, repeated mechanical dilations, 4 implant of biological 8 or synthetic tissues 9 , prosthesis, [10][11][12][13] or recently with the use of homologues or heterologues tracheal transplantation. [14][15][16] The surgical treatment for extensive stenosis of trachea is not a consensus amongst numerous and controversial surgical proceedings.…”

Multi-Scale Modification of Metallic Implants With Pore Gradients, Polyelectrolytes and Their Indirect Monitoring <em>In vivo</em>

“…Openly porous metallic implants are promising materials for tissue interface engineering and also for ensuring good colonization of the implants. They have been actively used as orthopedic implants and also as tracheal implants [3][4][5] . However, there are still problems that need to be solved such as the precise control over cell movement in the pore areas.…”

Tissue Engineered Trachea Using Decellularized Aorta

“…However, this established method is not appropriate for the repair of extensive lesions. Therefore, for these types of lesions other replacement methods, such as autografts [2,3], allografts [4,5], prosthetics materials [6][7][8] and tissue engineering [9][10][11][12] have been studied and developed. Some partial successes have been announced with some of these methods, butso far not one of them has archived a completely satisfactory long-term tracheal replacement for extensive lesions of the trachea.…”