Effect of chewing training on mandibular postural position

The inter-occlusal rest space (free-way space) was studied before and after short and long periods of chewing of a hard resin in 15 healthy subjects. During a month of daily training for one hour of chewing no significant changes in the interocclusal rest space were seen. After 30 min of intense chewing the mean interocclusal distance increased to about twice its original size. This occurred both before and after the training period. In a control group of eight subjects without any chewing exercise no significant changes in the interocclusal rest space were noticed during the observation period.