Evaluation of Autogenous Engineered Septal Cartilage Grafts in Rabbits: A Minimally Invasive Preclinical Model

Abstract

Objectives. (1) Evaluate safety of autogenous engineered septal neocartilage grafts and (2) compare properties of implanted grafts versus controls. Study Design. Prospective, basic science. Setting. Research laboratory. Methods. Constructs were fabricated from septal cartilage and then cultured in vitro or implanted on the nasal dorsum as autogenous grafts for 30 or 60 days. Rabbits were monitored for local and systemic complications. Histological, biochemical, and biomechanical properties of constructs were evaluated. Results. No serious complications were observed. Implanted constructs contained more DNA (P<0.01) and less sGAG perDNA (P<0.05) when compared with in vitro controls. Confined compressive aggregate moduli were also higher in implanted constructs (P<0.05) and increased with longer in vivo incubation time (P<0.01). Implanted constructs displayed resorption rates of 20–45 percent. Calcium deposition in implanted constructs was observe. Conclusion. Autogenous engineered septal cartilage grafts were well tolerated. As seen in experiments with athymic mice, implanted constructs accumulated more DNA and less sGAG when compared with in vitro controls. Confined compressive aggregate moduli were higher in implanted constructs. Implanted constructs displayed resorption rates similar to previously published studies using autogenous implants of native cartilage.