The efficacy of Gore-Tex vs. hydroxyapatite and bone graft in reconstruction of orbital floor defects

Fractures of the orbital floor often need to be reconstructed with rigid materials that provide a stable orbital floor and reestablish the correct orbital volume. In addition to autologous bone grafts, many alloplastic materials are available such as hydroxyapatite and, recently, expanded polytetrafluoroethylene reinforced with fluorinated ethylene propylene also known as reinforced SAM Gore-Tex. This study compared the efficacy and biocompatibility of reinforced and nonreinforced SAM Gore-Tex to those of hydroxyapatite and autogenous bone graft for reconstructing the orbital floor. A defect measuring 1.5×1.0 cm was created in the left orbital floor in 24 short-hair cats while the right side served as the control. The cats were divided into four groups, the defect being reconstructed with an autogenous iliac crest corticocancellous bone graft (group A), hydroxyapatite (group B), nonreinforced Gore-Tex (group C), or reinforced Gore-Tex (group D). Computed tomography was performed postoperatively at 1 and 8 weeks, and at the conclusion of the study specimens from the left orbit were harvested to evaluate the histological biocompatibility of each material. Reinforced SAM Gore-Tex possessed excellent physical properties. It was malleable yet firm enough and therefore easily contoured during repair of the defect while strong enough to support the orbital contents. It could even be sutured to the orbital rim or a fixating plate to ensure further stabilization, if necessary. Additionally, the material demonstrated exemplary biocompatibility as it initiated a minimal inflammatory response. As healing progressed, a growth of host tissue into the material was noted in all histological specimens, thereby augmenting the stability of the implant and reducing the incidence of extrusion.