Determination of mandibular border and functional movement protocols using an electromagnetic articulograph (EMA)

The electromagnetic articulograph (EMA) is a device that can collect movement data by positioning sensors at multiple points, measuring displacements of the structure in real time, as well as the acoustics and mechanics of speech using a microphone connected to the measurement system. The aim of this study is to describe protocols for the generation, measurement and visualization of mandibular border and functional movements in the three spatial planes (frontal, sagittal and horizontal) using the EMA. The EMA has transmitter coils that determine magnetic fields to collect information about movements from sensors located on different structures (tongue, palate, mouth, incisors, skin, etc.) and in every direction in an area of 300 mm. After measurement with the EMA, the information is transferred to a computer and read with the Visartico software to visualize the recording of the mandibular movements registered by the EMA. The sensors placed in the space between the three axes XYZ are observed, and then the plots created from the mandibular movements included in the corresponding protocol can be visualized, enabling interpretation of these data. Four protocols for the obtaining of images of the opening and closing mandibular movements were defined and developed, as well as border movements in the frontal, sagittal and horizontal planes, managing to accurately reproduce Posselt's diagram and Gothic arch on the latter two axes. Measurements with the EMA will allow more exact data to be collected in relation to the mandibular clinical physiology and morphology, which will permit more accurate diagnoses and application of more precise and adjusted treatments in the future.