Electromyographic evidence for sufficient and insufficient developmental space in juvenile jaws

概要

論文の詳細を見る
The aims of the present study were twofold : to observe developmental changes in masseter muscle activity and developmental space, and to test the relationship between masseter muscle function and developmental space as an indicator of jaw growth. The subjects comprised 176 day nursery children aged from one to six years. EMG recordings of masseter muscle activities on magnetic tape during chewing and dental assessment of occlusion were used. The mean values for total chcwing time, duration of a chewing burst, cycle time and the coefficient of variation of each measurement decreased with age ; whereas the 0-to-peak amplitude and integrated amplitude increased steadily. Developmental space increased with age. The subjects were devided into five groups following cluster analysis of several measurements from the EMG data. The masseter muscle function was thought to be more mature in the higher numbered groups. Normal occlusions both with and without developmental space were considered in further analysis. Comparing subjects with Hellmans' dental age IIA over three years old, normal occlusion was significantly predominant in the matured muscle activity groups of clusters 4 and 5, and the pseudo-normal occlusion in the immature groups of Clusters 1 and 2 (Fisher's exact test, p<0.05). These findings suggested that insufficient developmental space is a consequence of insufficient masseter muscle activity in the early stages of life.
日本矯正歯科学会の論文

Electromyographic evidence for sufficient and insufficient developmental space in juvenile jaws

スポンサーリンク

概要

著者

関連論文

スポンサーリンク