[Application of the "Wits" approsal in Shanghai children with normal mixed or early permanent dentition]

128 children in Shanghai with normal mixed or early permanent dentition were selected in this servey to gain their normal value of the "wits" approsal.The results showed (1) there was no significant difference of "wits" approsal between the two groups of the children. (2)There was no disparity in "wits" approsal ofthe children with the same nationality and living in different regions. (3) There was a little change in value of the "wits" apporsal during the growth period or the children,which indicated a comparative identical relationship between the upper and lower basal bone.This study suggested that the application of the "wits" approsal be very imnportant in orthodontic clinic because of its expressing exactly the relationship of the jaws.