[Three-dimensional measurement of tooth inclination in cases with successful treatment].
OBJECTIVE
This study aimed to observe the differences of tooth inclinations among post-treatment good cases of different malocclusions and untreated normal occlusions in order to give references on clinical adjusting of tooth inclinations.


METHODS
157 post-treatment good cases were chosen and tooth inclinations were measured on post-treatment casts using YM-2115 three-dimensional measurement instrument. The measurement results were compared with those of untreated normal occlusions.


RESULTS
The inclination values of upper and lower incisors of Class I groups are most close to those of untreated normal occlusions, which of upper central and lateral incisors are 9.6 degrees and 8.7 degrees, and of lower central and lateral incisors are 1.1 degrees and -1.1 degrees. In Class II groups, lower incisors are markedly proclined (5.6 degrees and 2.1 degrees) and upper incisors are similar with untreated normal occlusions. In Class III groups, upper incisors are markedly proclined (15.2 degrees and 12.1 degrees) and lower incisors are markedly retroclined (-3.7 degrees and -4.9 degrees).


CONCLUSIONS
In order to achieve normal overjet and overbite, it is necessary to adjust the inclinations of upper and lower incisors when treated Class II and Class III malocclusions only by the method of orthodontic treatment.
Yang
Minzhi
M
Department of Orthodontics, Peking University Stomatological Hospital, Beijing 100081, China.
Xu
Tianmin
T
Lin
Jiuxiang
J
D006801:Humans; D007180:Incisor; D008312:Malocclusion, Angle Class II / Q000628:therapy; D008313:Malocclusion, Angle Class III / Q000628:therapy; D014087:Tooth Movement Techniques