Identification of Biomechanical Properties of Temporomandibular Discs

Abstract

Purpose of the Paper. The study was aimed at identifying the biomechanical properties of the temporomandibular disc. Material. Experimental and model tests were conducted on ten fresh porcine temporomandibular joint discs. The average thickness of disc tissue was, accordingly, 2.77 mm for the anterior zone, 3.98 mm for the posterior, and 1.54 mm for the intermediate. The selection of research material in the form of porcine discs was due to the similarity to human discs. Methods. Discs were loaded in cycles, a temporary course with the amplitude 3 N and frequency 0.07 Hz, and growth in the load was 1 N/s. The selection of load frequency was due to real conditions of temporomandibular joint functioning during mastication. The necessary experimental research was conducted on a testing machine with a measurement range of 2.5 kN. Results. The obtained numeric calculation results indicate that the number of load cycles has a decisive impact on the limitation of energy dispersion capacity through disc tissue. This phenomenon was observed in all the studies on the disc areas. Along with the growth in load cycles, discs are stiffened, and the most significant stiffness was observed in the intermediate area. Conclusions. Based on the conducted research, it should be concluded that excessive load affecting temporomandibular joints caused by the act of mastication and occlusal forces generated during parafunction and in people with defined long-term bruxism has crucial importance on biomechanical disc properties and hence the course of temporomandibular joint conditions.

Fracture Toughness of Ovine TMJ Disc: Effects of Crack Length and Orientation

“…The meshes for the nite element model were iteratively re ned until the discrepancy in the J contour integral was below 1% between two consecutive meshes. The TMJ disc's mechanical behavior characterized as linear viscoelastic isotropic [7,27]. The Prony coe cients are shown in The cut specimens in AP group had lower overall size than ML group due to less available length in this direction.…”

“…Without the TMJ, regular tasks such as speaking, eating, and drinking would be di cult. The TMJ allows complex jaw motions and absorbs mechanical force [6][7][8]. Since the TMJ allows both translational and rotational motions, it helps the jaw move smoothly with the skull.…”

Research progress on dynamic three-dimensional finite element model construction of temporomandibular joint

“…For structures that require precise consideration of deformation variables, such as joint discs, joint cartilage, and joint capsules, if simple characterization is still used using elastic modulus and Poisson's ratio, the simulation accuracy will be poor. TMJ joint disc is actually a nonlinear, dual phase material with viscoelasticity and hyperelasticity [14] . At present,most studies still use the Mooney Rivlin nonlinear elastic model (a hyperelastic model similar to rubber) to analyze the joint disc [15,17] , without taking into account the viscoelasticity of the joint disc.…”