Model identification of stomatognathic muscle system activity during mastication

Abstract

The present study aimed to determine the numeric projection of the function of the mandible and muscle system during mastication. An experimental study was conducted on a healthy 47 year-old subject. On clinical examination no functional disorders were observed. To evaluate the activity of mastication during muscle functioning, bread cubes and hazelnuts were selected (2 cm2 and 1.2/1.3 cm in diameter, respectively) for condyloid processing. An assessment of the activity of mastication during muscle functioning was determined on the basis of numeric calculations conducted with a novel software programme, Kinematics 3D, designed specifically for this study. The efficacy of the model was verified by ensuring the experimentally recorded trajectories were concordant with those calculated numerically. Experimental measurements of the characteristic points of the mandible trajectory were recorded six times. Using the configuration coordinates that were calculated, the dominant componential harmonics of the amplitude-frequency spectrum were identified. The average value of the dominant frequency during mastication of the bread cubes was ~1.16±0.06 Hz, whereas in the case of the hazelnut, this value was nearly two-fold higher at 1.84±0.07 Hz. The most asymmetrical action during mastication was demonstrated to be carried out by the lateral pterygoid muscles, provided that their functioning was not influenced by food consistency. The consistency of the food products had a decisive impact on the frequency of mastication and the number of cycles necessary to grind the food. Model tests on the function of the masticatory organ serve as effective tools since they provide qualitative and quantitative novel information on the functioning of the human masticatory organ.

Evaluation of the Masticatory Efficiency at the Patients with New Complete Dentures

“…The examinees non experienced on complete dentures, in the beginning, have had a shorter duration of SMT comparing to the examinees experienced on complete dentures, but in the end, the values of the final duration of SMT were the same (NE and E group). This can be explained by neurophysiologic models of mastication since they provide a lot of information on the functioning of the masticatory organ in human [ 21 ].…”

“…Efficient SMT can be performed in a shorter time with a smaller number of masticatory cycles but with a higher maximal amplitude of the masticatory arch. According to Kijak E et al [ 21 ], the consistency of the food products had a decisive impact on the frequency of mastication and the number of cycles necessary to grind the food.…”

Identification of Biomechanical Properties of Temporomandibular Discs

“…Such a frequency approximately corresponds to real-functioning conditions of the temporomandibular joints during mastication. The frequency was determined based on own chewing measurement data recorded with the Zebris JMA electronic facial arch in a healthy, model patient [ 39 ]. The experimental studies do not reproduce the actual movement that takes place in the temporomandibular joints because it is so complicated that it is difficult to reproduce it on a testing machine.…”

Newly developed mastication activity reduction procedure rapidly induces abnormal atrophic change of the mandibular condyle in young and elder experimental animal models

“…Tendons and ligaments contribute to limitation of jaw movement. Teeth can crush, grind and mix foods with saliva secreted from the salivary glands to form a bolus for swallowing, in cooperation with the tongue and cheek muscles [7,8]. Sense receptors are present in the oral cavity, while the masticatory pattern generator provides brainstem control over masticatory activity [7,9,10].…”