[Effect of chewing training on the postural position of the mandible]

The aim of this project was to study possible effects of chewing gum training on the postural position of the mandible. The material consisted of 11 male and 14 female dental students which were divided in to an experimental and a control group. The subjects were thoroughly informed about the experiment and participated voluntarily. The participants were in good health had a complete natural dentition and had no complaints of mandibular dysfunction. They started chewing-gum training, one hour daily, for one month. The chewing-gum used for this experiment was the resin obtained of the bark of the mastiche tree grown in the greek island Chios which was selected because of its hardness in chewing. In every registration, free way space was measured 4 times with the phonetic method and the mean value was estimated at 5 different occasions. (15 days before the start of the experiment, the day the experiment started before and after half an hour chewing training, and at the end of the experiment, after one month systematic chewing training, one hour daily, free way space was measured again before and after half an hour chewing training. The results of this clinical experimental work indicate: 1) Systematic chewing training does not have any effect on the mandibular postural position of the mandible. 2) Fatigue of the stomatognathic system musculature, caused by half an hour chewing training, very significantly alters the mandibular postural position as it doubles free way space. A possible clinical use of these findings is that free way space does not correlate with the rate of use of the stomatognathic system.(ABSTRACT TRUNCATED AT 250 WORDS)