A Comparison of the Mechanical Properties of the Goat Temporomandibular Joint Disc to the Mandibular Condylar Cartilage in Unconfined Compression

The aim of this study was to make a comparison of the compressive properties of the goat temporomandibular joint (TMJ) disc to the mandibular condylar cartilage (MCC) and to explore the transversely isotropic biphasic model. Samples taken mediolaterally from three regions of the TMJ disc and MCC were tested in unconfined compression at strain levels ranging from 10% to 50% and then assessed for biochemical content. The results indicated that the TMJ disc exhibits a significantly greater tangent modulus than the MCC from 20% to 50% strain with values ranging from 729 ± 267 to 2413 ± 406 kPa and 363 ± 169 to 1677 ± 538 kPa, respectively (P < .05). The collagen content of the TMJ disc was significantly greater than the MCC, while the opposite held for the glycosaminoglycan (GAG) and DNA content. The results emphasize fundamental differences between the articulating tissues of the TMJ.