Evaluation of the Masticatory Muscles Temperature by Thermal Imaging During Mastication

The mastication is the first step in the digestion process and has as an objective prepare the food for the swallowing process and procession by the digestive system. (1-3) The masticatory sequence begins with the introduction of the food in the oral cavity, and ends with the swallowing of the bolus (2, 4, 5). Each masticatory sequence is a set of masticatory cycles, each cycle is composed by a opening, closing, and side movements (2, 4). The rhythm is the main characteristic of the mastication process (4). The masticatory rhythm is generated by the Central Pattern Generator, that active a motor program, and coordinate the mandibular, tongue and facial muscles movements. (1, 4). There are a lot of methods that can be used for the study and analysis of the mastication function, one of those methods is the surface electromyography, that records the bioelectrical potentials of the masticatory muscles, trough electrodes placed in the skin surface(4-6). These bioelectrical potentials are related with the strength developed by the muscle during the mastication. So surface electromyography is a widely used method in studies that relate the muscle activity in the masticatory process (4-6). Infrared termography has been used in medical applications to evaluate cutaneous blood flow adaptation during a specific function like in swimming were it was possible to observe significant variations in the cutaneous temperature according to swimming styles (7). This work had as main goal, to study the application of infrared termography in the mastication process and to see a possible correlation beetween the values obtained with the electromigraphy.