A Study of the Relationship between the Development of Skeletal Malocclusion and the Tooth Crowding in Posterior Part of Dentition

骨性错牙合畸形的发生与后牙列牙列拥挤关系的研究

• 批准号: 03670983
• 负责人: SATO Sadao
• 金额: $ 0.77万
• 依托单位: Kanagawa Dental College
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1991
• 资助国家: 日本
• 起止时间: 1991 至 1992
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-03670983/
• 关键词: Discrepancy; Skeletal Malocclusion; Over Eruption; Vertical Dimension; Monkey; Mandible; Growth; 骨格性不正咬合; ディスクレパンシ-; 咬合高径; 顎顔面の成長

In order to clarify the relationship between the development of skeletal malocclusion and the over eruption of molars due to posterior tooth -to-denture base discrepancy, a model experiment using monkeys have done in this study. Metal crowns were made and fixed on the right and left maxillary first molars of experimental animals to increase the vertical dimension of occlusion. This procedure was duplicated after one month of fixing the first crown and providing the increasing 2mm of the vertical dimension totally.Growing animal indicated that the forward displacement of the mandible followed by the condylar growth was associated with increasing the molar height. This response of the mandible induced the anterior cross bite of occlusion. However, adult animal showed that the backward rotation of mandible was induced by the increasing vertical dimension, providing the anterior open bite occlusion. These findings are suggesting that the molar over eruption due to posterior discrepancy is one of the important etiologic factors in the development of skeletal malocclusion such as skeletal class III and skeletal open bite.

为了阐明骨性错牙合畸形的发生与后牙与义齿基托不等导致的磨牙过度萌出之间的关系，本研究利用猴子进行了模型实验。在实验动物左右上颌第一磨牙上制作金属冠并固定，以增加咬合的垂直尺寸。在固定第一个牙冠一个月后重复该过程，并提供总共增加2毫米的垂直尺寸。生长动物表明，下颌骨向前移位，随后髁突生长与磨牙高度的增加有关。下颌骨的这种反应引起咬合的前牙反咬合。然而，成年动物表明，下颌骨的向后旋转是由垂直尺寸的增加引起的，从而提供了前牙咬合。这些发现表明，由于后牙差异而导致的磨牙过度萌出是骨性错牙合（例如骨性III类和骨性开牙合）发展的重要病因之一。