[Adaptation of mastication in response to the characteristics of the individual or the food].

This article describes how all individuals formulate an individual masticatory adaptation process to deal with the special characteristics of the food they are chewing. It begins by briefly reviewing the act of mastication and the principal techniques that are used to observe it, focusing especially on electromyography. An overall study of mastication must include an analysis of its result, that is, the bolus of food that it prepares for swallowing. The masticatory act varies with each individual; it has been clearly established that people do not effect the same mandibular movements when they chew. Some people will need more chewing cycles to treat the same bolus of food than others will and the amplitude and duration of muscular contraction will vary from individual to individual. But a certain reproducibility does exist for each subject. The patients' dental condition will, to a large extent, dictate how they chew. The more prosthetic replacements they have in their mouths, the more cycles they will require for mastication. Age, too, plays a role. Older people have diminished perception thresholds and, therefore, take longer to react. If their dentitions are relatively complete and healthy, they simply need to increase the number of chewing cycles for a given portion of food. And, of course, the texture of the foodstuff plays a part; the harder it is the greater the number of cycles will be.