Transmigration Process of the Impacted Mandibular Cuspid
In the course of our consecutive observation of 304 grade school children by means of periodic radiography, attention was drawn to a case of impacted 3_??_ in one of the examined. Therefore, it was subjected to chronological examinations extending for a period of 8 years.The impacted tooth gradually migrated from its cusp through the body of the mandible and the root region of anterior teeth to a spot beneath the mental foramen on the opposite side, having gone through the symphysis. At present, its apex is found to lie beneath the apex of 1_??_ and it is tilted lingually in the body of the mandible. However, there has been noted no particular influence such as oppression of the mandibular nerve owing to the transmigration of the said impacted tooth.
This study was focussed on the effects of changes in interocclusal clearance on the activity of oral muscles. Two types of occlusal splints were incorporated in 20 subjects without TMJ-syndrome. Their muscle reactions were recorded electromyographically in the masseter muscle. The results show 5 groups of muscle reaction correlated with the mean postural face height. The changed height of the postural position has a significant influence on the control pattern of the masticatory system.