15502-m-pleumeekers

Statistical analysis Biochemical differences were analysed using Mixed Models with Bonferroni correction. Differences in effective Young’s modulus between groups were determined through Generalized Estimating Equations. To measure the correlation between stiffness and biochemical content a Bivariate Correlations Model was used. All analyses were performed using PASW Statistics 22.0 (SPSS inc. Chicago, USA). A p -value of less than 0.05 was considered significant. Figure 1. Overview of indentation and multi-photon laser microscopy technology. (A) Set-up of cantilever indentation device. (B) Example of indentation curve of a cartilage measurement. Red tangent represents the slope of the unloading curve to determine the effective Young’s modulus. (C) Graphic detail of the indenter tip. The ball forms the tip of the indenter (Ø 78 µm). (D) Optical set-up of multi-photon laser-scanning microscope TriMScope I. (E) SHG channel showing collagen bundels. (F) 2PF channel showing elastin fibers. IR-PD = Infrared laser diode ; IR-L = Infrared laser ; OF = Optical Fiber ; CIT = Cantilever Indentation Tip. Ti = Titanium ; GS = X-Y Galvo Scanner mirrors ; SL = Scan Lens ; TL = Tube Lens ; DM = Dichroic Mirror ; MO = Microscope Objective ; BP = Band-Pass filters ; L = Lenses in front of the PMTs ; PMT = PhotoMultiplier Tubes. 49 FACIAL CARTILAGE CHARACTERISTICS 3