Objective
To determine and compare the bending moduli of native and engineered human septal cartilage.
Study Design
Prospective, basic science.
Setting
Research laboratory.
Subjects and Methods
Neocartilage constructs were fabricated from expanded human septal chondrocytes cultured in differentiation medium for 10 weeks. Constructs (n=10) and native septal cartilage (n=5) were tested in a 3-point bending apparatus, and the bending moduli were calculated using Euler–Bernoulli beam theory.
Results
All samples were tested successfully and returned to their initial shape after unloading. The bending modulus of engineered constructs (0.32 ± 0.25 MPa, mean ± SD) was 16% of that of native septal cartilage (1.97 ± 1.25 MPa).
Conclusion
Human septal constructs, fabricated from cultured human septal chondrocytes, are more compliant in bending than native human septal tissue. The bending modulus of engineered septal cartilage can be measured, and this modulus provides a useful measure of construct rigidity while undergoing maturation relative to native tissue.
Objectives
Evaluate safety of autogenous engineered septal neocartilage grafts.
Compare properties of implanted grafts versus in vitro controls.
Study Design
Prospective, basic science
Setting
Research laboratory
Methods
Constructs were fabricated from septal cartilage and serum harvested from adult rabbits 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 implanted and in vitro constructs were evaluated and compared.
Results
No systemic or serious local complications were observed. After 30 and 60 days, implanted constructs contained more DNA (p<0.01) and less sGAG per DNA (p<0.05) when compared with in vitro controls. Confined compressive aggregate moduli were also higher in implanted constructs when compared with in vitro controls (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 observed using alizarin red histochemistry and microtomographic analyses.
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 also higher in implanted constructs. Implanted constructs displayed resorption rates similar to previously published studies using autogenous implants of native cartilage. The basis for observed calcification in implanted constructs and its effect on long-term graft efficacy is unknown at this time and will be a focus of future studies.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.