Examination of strength properties of the temporomandibular joint disc

The purpose of this research was to determine selected biomechanical properties of the temporomandibular disc. After endurance tests and once the load-displacement characteristics were determined, the susceptibility and dimensionless energy dissipation coefficient were determined. The research was carried out on ten discs (six fresh and four frozen) taken from five young pigs. Endurance tests were conducted in the laboratory of Wrocław University of Science and Technology, using the INSTRON 5944 machine. All tested discs were kept in a NaCl solution heated to 37.5ºC during the experiment. A recurring difference of 1 mm in the height of the fresh and frozen discs was observed. In contrast, the strength of the discs was similar regardless of the method of storing the preparation. The material susceptibility values ranged from 0.4 to 1.4 millimetre per Newton, and the dimensionless energy dissipation factor oscillated between 0.27 and 0.87. The aim of these experimental investigations was to determine the compressive force at predefined strain levels and to elucidate the loading characteristics corresponding to displacement. Due to the observed variability in these characteristics across consecutive measurement cycles, the analysis in this paper is restricted to the results obtained from the first measurement series.