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Author Spotlight: 3D Movement Assessment of Maxillary Posterior Teeth in Clear Aligner Treatment
Published on: February 23, 2024
Differences in the mandibular premolar positions in Angle Class I subjects with different vertical facial types: A
Jun Duan1, Feng Deng2, Wan-Shan Li1
1Department of Stomatology, Ministry of Education Key Laboratory of Child Development and Disorders, Children's Hospital of Chongqing Medical University, Chongqing, China.
Objective:
To compare the positions of the mandibular premolars in Angle Class I subjects according to vertical facial type. The results will provide a theoretical basis for predicting effective tooth movement in orthodontic treatment.
Methods:
Cephalometric parameters were determined using cone-beam computed tomography in 120 Angle Class I subjects. Subjects were categorized as short, normal, and long face types according to the Frankfort mandibular angle. Parameters indicating the position of the mandibular right premolars and the mandible were also measured.
Results:
The angle between the mandibular first premolar axis and buccal cortex, the distance between the root apex and buccal cortex, angle of vestibularization, arc of vestibularization, and root apex maximum movable distance were significantly greater in the short face type than in the long and norm face types. The angle between the mandibular second premolar axis and buccal cortex, the distance from root apex to buccal cortex, and the arc of vestibularization were significantly greater in the short face type than in the normal face type.
Conclusions:
There are significant differences in the mandibular premolar positions in Class I subjects according to vertical facial type.
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