[Morphologic characteristics of anterior crossbite in early permanent dentition reviewed by superimposition on the template].
OBJECTIVE
To establish a computer-processing module to first, eliminate the factors which mislead the diagnosis of anterior crossbite and second, superimpose the individual tracing on the template to review the patient's morphologic characteristics.


METHODS
First, the module would process the following steps:1.to create three templates; 2.to move the functional-shift-mandible posteriorly; 3.to standardize the potential of vertical dimension;4.to select a suitable template for superimposition; 5.to standardize the sizes of individual graph and template. Second, the module would process the five-step superimpositions: 1. X axis was superimposed and S were registered to measure the distances between Ptm points and Ar points on X axis; 2. X axis was paralleled and Ptm were registered to measure the distance between A points on X axis; 3. X axis was paralleled and A points were registered to measure the difference of anterior area between the mandibular graphs; 4.mandibular planes were superimposed and Po was registered to show the mandibular form variation; 5. Ar-Gn lines were superimposed and Ar was registered to measure the difference between the mandibular graphs.


RESULTS
The module which could complete these steps was produced. With its help, the individual graph could be diagnosed with the position of maxilla and mandible, the amounts of maxillary discrepancy and jaws' dysplasia, the mandibular form and size variation.


CONCLUSIONS
The module could eliminate the factors which mislead the diagnosis and review the morphologic characteristics of anterior crossbite in early permanent dentition.
Chen
Lin-ling
LL
Department of Orthodontics, School of Stomatology, Ninth People's Hospital,Shanghai Second Medical University, Shanghai 200011, China. luyao@public4.sta.net.cn
Peng
Shi-sheng
SS
Liu
Hong-hu
HH
Cao
Hui-ju
HJ
Li
Guang-yao
GY
D019229:Dentition, Permanent; D003936:Diagnosis, Computer-Assisted; D006801:Humans; D008310:Malocclusion / Q000473:pathology*