Digital Analysis of Kinematics and Electromyography During the Masticatory Cycle

Objectives During dental rehabilitation, comprehensive evaluation of the stomatognathic system is standard procedure. Meticulous masticatory function analysis could be necessary if modifications involve the occlusal area, to restore physiology. Among these analyses, the evaluation of mandibular kinematics and muscle activity plays a strategic role in understanding stomatognathic functions and assessing temporomandibular dysfunctions (TMD). In gnathology, it is common to separately analyse jaw movement and muscle activity during mastication. Results were also evaluated independently. The primary objective of this study was to investigate the complex interplay between mandibular kinematics and surface electromyography (sEMG) activity during the masticatory cycle using advanced digital technology in healthy subjects (without TMDs). Methods Twenty-two dental students (11 F, 11 M) of Vita-Salute San Raffaele University in Milan (average age 25 ± 2.88 years) voluntarily underwent a recording of the masticatory cycle. This study was approved by the ethical committee of IRCCS San Raffaele Hospital (Milan, Italy) under protocol document GNATHOLOGY (cod: opinion09/int/2023) Results The BTS TMJOINT sEMG device from BTS Bioengineering (© 2023) was used to detect the electrical activity of the masticatory muscles during chewing, activation sequence and coordination. However, mandibular movements and condylar slopes were recorded using ModJaw® (Tech in motion™, Villeurbanne, France). The obtained parameters were analysed using descriptive and inferential statistics. Conclusions Integrating muscle and joint analysis aids clinicians in diagnosing and comprehending stomatognathic interactions. Combining electromyography and kinematic data offers holistic insights into muscle-motion connections, deeps clinical understanding and offers personalised interventions for patients with TMD.