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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.

Oral PresentationsP37 drawings using this method. The authors suggest a recording system using a mobile device and have found it useful in storing and transmitting the drawings.Methods: Based on iPad 4.0, the rhinoplasty record application program (Rhinograph) was developed. The SQLite was used as an internal database, and the program was developed using XCode 4. The authors kept the operation records of 10 patients who had undergone rhinoplasty and confirmed the usefulness and convenience of this system. Results:The program was divided into 6 parts: 1) the operation sheet (operation registration, surgical details, and notations), 2) looking up, modifying, and converting the system to PDF/ JPG files with email transmissions, 3) the template developing system with frequently used techniques, 4) the database backup and conversion to Excel files, 5) registering user emails and signatures, and 6) the description of the applications. The program resulted in equal convenience and accuracy as hand-drawing among the 10 patients. In addition, the mobile device was easily carried in the operating room and outpatient clinics.Conclusions: The rhinoplasty recording system using a mobile device was found to be as effective as the traditional way of recording and helped remove the constraints of place. In addition, it was shown to be convenient to store and analyze the data.

Objective: 1) Determine the flexural modulus (intrinsic flexibility) of tissue-engineered human septal neocartilage constructs using 3 point bending mechanical testing. 2) Compare the flexibility of native human septal cartilage to human tissue-engineered septal cartilage constructs using 3-point bending mechanical testing. Method: Strips of tissue-engineered human septal neocartilage and native septal cartilage were subjected to 3-point bending using a testing apparatus with axial load cell and actuator. Uniform stress was applied while displacement and strain were recorded. The flexural rigidity or bending modulus was calculated for each sample. Results: After 10 weeks in culture, the flexural modulus of tissue-engineered human septal neocartilage constructs was 0.462 N/mm2 versus 3.28 N/mm2 for native tissue ( P = .002). No samples fractured or demonstrated plastic deformation. Conclusion: Tissue-engineered septal neocartilage was 7.1-fold more flexible than native septal cartilage. This study demonstrates that flexural moduli of tissue engineered septal cartilage can be determined after 10 weeks in culture, providing a useful measure of construct properties relative to native tissue.