Figure 5

Preparation of substrate tissues. Schematic graphs and pictures illustrating the preparation of substrate tissue cylinders used for the determination of bonding strength. Osteochondral discs of 1–1.5 cm thickness (b) were obtained from the lateral and medial condyle of pig femoral bones (a) using a rotary reciprocating saw. (c) The removed discs were hole-punched to generate a cylindrical tissue specimen with a diameter of 10 mm. A bench vise facilitated a controlled agitation of the punch orthogonal to the sectional plane. (d) The raw tissue cylinder was placed in a customized grip that is fitting into the jig of a standard microtome device (see also Figure 4a). (e) Using the blade of the microtome the surface of the tissue cylinder was leveled to obtain regular bone or cartilage cylinder ends. Thus, starting from a raw cylinder (d), cartilage and bone substrate cylinders with plane surfaces can be generated (h). Furthermore, with the help of a smaller punch (ø 6 mm) another hole was created (f) providing an artificial cartilage defect to be filled with cartilage tissues or transplants (g, i).