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Relationship between ear canal deformation and mandibular condyle movement using an earplug-type sensor
Junrong Qi1, Takafumi Kato2, Miki Nakaza3
1Department of Orthodontics, Matsumoto Dental University, Nagano, Japan.
Objectives:
To clarify the relationship between ear canal deformation and mandibular condyle movement, and to evaluate the feasibility of estimating jaw movement with an earplug-type sensor.
Methods:
Sixteen healthy individuals participated in the study. Ear canal deformation was recorded using an earplug-type sensor equipped with a barometric pressure sensor. Mandibular condyle movement was recorded simultaneously using a six-degree-of-freedom jaw-tracking system. Cross-correlation analysis was performed to examine the relationships between ear canal deformation and the anteroposterior, mediolateral, and vertical components of condyle movement, during opening-closing, lateral, and chewing movements.
Results:
During opening-closing movements, strong correlations were observed for all directional components (0.84-0.88). During lateral and chewing movements, correlation coefficients were significantly greater on the balancing side than on the working side (p < 0.05). The mediolateral component showed weaker correlations than the anteroposterior and vertical components.
Conclusions:
Ear canal deformation recorded using an earplug-type sensor was strongly correlated with mandibular condyle movement. These findings suggest that monitoring ear canal deformation may provide a simple, non-invasive method for assessing mandibular movement.
