Longitudinal evaluation of the intermaxillary relationship in Class III malocclusions.
OBJECTIVE
To analyze the sagittal, vertical, and transverse relationship of the maxilla and mandible in Japanese girls with Class III malocclusions.


METHODS
This longitudinal study utilized biannual posteroanterior and lateral cephalograms of 44 untreated subjects from age 8 to 14 years (Class I, 23 girls; Class III, 21 girls). Sagittal and vertical growths were analyzed on the basis of lateral cephalograms, and transverse growth was analyzed on the basis of posteroanterior cephalograms.


RESULTS
There was no significant difference in sagittal intermaxillary relationships in Class III malocclusion from age 8 to 14 years, whereas significant difference in vertical and transverse intermaxillary relationships appeared with ages during this period. When comparing Class III to Class I malocclusions at the same age point, there were significant differences in sagittal and transverse intermaxillary relationships, whereas significant difference in vertical intermaxillary relationship appeared after 12 years of age.


CONCLUSIONS
The results suggest that the sagittal intermaxillary relationships in Class III malocclusions were established before 8 years of age and remained through puberty and that the vertical and transverse intermaxillary relationships in Class III malocclusions changed with ages from 8 to 14 years.
Chen
Fengshan
F
Niigata University, Department of Orthodontics, Niigata, Japan. chenfengshan@hotmail.com
Terada
Kazuto
K
Wu
Liping
L
Saito
Isao
I
D000293:Adolescent; D044466:Asian People; D016022:Case-Control Studies; D002508:Cephalometry; D002648:Child; D005260:Female; D006801:Humans; D007564:Japan; D007574:Jaw Relation Record; D008137:Longitudinal Studies; D008313:Malocclusion, Angle Class III / Q000503:physiopathology*; D008445:Maxillofacial Development