切牙骨

METHODS: Measurement of palatal raphe area first three-dimensional reconstruction of images at up to nasion plane centerline, whichever was determined as a reference surface plane, selection one point on incisor cervix in this line, to measurement of the available palatal bone height; sagittal views were selected at 6 mm dorsally from the incisive canal. The available bone height was defined as the distance from the palatal baseline (lower cortical border of the palate) to the nasal cavity (upper cortical border of the nasal cavity).

先在三维重建图像上以鼻根为准确定面中线平面为参考平面，在此线上选择1个位于中切牙牙颈部的点，在其矢状位图像上，选取位于口腔内侧骨皮质上距切牙孔后缘6 mm处为标测点，通过此点向硬腭做垂线确定腭骨厚度，测量范围自口腔内腭部骨皮质外侧边缘至鼻腔侧骨皮质外侧边缘。

Res ults: The maxillary central incisor was similar to the maxillar y lateral incisor in stress distribution. The highest stresses were observed in the root surface, the liwest in the periodontal ligament, the alveolar bone between them .

结果：上颌中、侧切牙的应力分布基本相同；上颌中、侧切牙及其支持组织的应力分布不均匀，牙根部受应力最大，牙槽骨次之，牙周膜最小。

Upper central incisors moved forward and downward together with maxillary, at the same time they upright in the sagittal plane and tip mesially. 3 The occlusion plane rotated clockwise for about 1.5°. 4 The width increasement effect of RME comes from approximately the equal amounts of skeletal and dental expansion. The mode of dental movement was a combination of body and tipping movements of posterior teeth.

结果：1后牙在宽度方向上为整体移动和倾斜移动相结合的移动方式，但第一磨牙和第一双尖牙稍有差别；牙齿和骨对宽度增加的贡献各占约1/2；2后牙在垂直方向有伸长的趋势；3第一磨牙和第一双尖牙均向前整体移动，轴倾度保持不变；4中切牙整体随上颌骨前部向前向下移动，其牙长轴发生直立，轴倾度增加；5上颌平面发生顺时针旋转。

The results of Pancherz analysis shows that the correction of negative overjet is mainly due to the advancement of maxilla and upper incisors. But the position changes of mandible and lower incisors imply that severe maxillary hypoplasia with high angle and/or mandibular retrusion is contraindicated by the method conducted in this study.

头影测量侧位片Pancherz分析法的分析结果表明，本研究中上颌后缩患者反覆盖的矫治主要由上颌骨、上切牙的前移引起的，但下颌骨和下切牙位置的变化提示适应症的选择应注意避免上颌后缩同时伴有高下颌角和／或下颌后缩的患者。

Its mechanism is downward and backward rotation of the mandible, the retrusion of the lower incisors, the protrusion of the upper incisors and the forward growth of maxilla.

FR-Ⅲ是矫治替牙期前牙反的理想方法之一，其机理是下颌骨向下、向后旋转，舌倾下切牙，唇倾上前牙，促进上颌骨向前生长。

The main changes were the downward and backward rotation of the mandible, the retrusion of the lower incisors, the protrusion of the upper incisors.FR-Ⅲ also promotes the growth of maxilla and reaches the normal relationship of the anterior overjet and overbite.

结果：FR-Ⅲ能矫正上下颌基骨异常的矢状关系，主要变化是下颌骨向下、向后旋转，改变下颌骨生长的方向，同时使下颌切牙舌倾、上前牙唇倾，上颌骨向前生长。

Cysts form anywhere in the incisive canal located in the palatine bone and behind the alveolar process of the maxillary central incisors, or in the palatal soft tissues that overlies the foramen, called the cyst of the incisive papilla.

无论是在切牙管任何位置的囊肿都位于上颌骨，上颌骨中切牙牙槽突的后方，或者在覆盖于壳顶孔上方的软组织内，这种又被称为龈乳头囊肿

With increasing resorption of alveolar bone, the center of resistance of the maxillary incisors including pulp cavity, were located within the mid-sagittal plane,6.1mm lingual to archwires labial side, respectively at 38.5 %, 47.3%, 55.2%, 64.1%, 75.2%length of the central incisor measured from the alveolar crest.

1、在不同程度齿槽骨吸收时上颔切牙段在各种载荷作用下，中切才｝侧切才的应力分介基木相同，均为丁恨表而应力最大，齿槽骨人山厂入上，丁人司膜应力最个。

BACKGROUND: Studies demonstrated that incisor continuously growing is due to lack of epithelial root sheath formation. However, researches regarding whether receptor activator of nuclear factor κB ligand and osteoclast has correlation with continue root development is poorly understood.

背景：研究表明小鼠不断生长的切牙是由于切牙仅有颈环而无上皮根鞘的形成，但是破骨细胞分化因子核因子κB受体活化剂配体和破骨细胞与不断生长的牙根发育是否相关，目前研究较少。

Of resorption in vertical and horizontal direction.The purpose of this article is to get the average values and standard deviation of the alveolar ridge heights of the upper and lower central incisors and the first permanent molors in adult with normal occlusion by cep...

测量正常成年人60名的结果提示利用新定的标志和线距对无牙颌原有的上下中切牙和第一磨牙的位置有了确定的方法和数据，进而可测得无牙颌牙槽骨的吸收量，因而扩大了头影测量的临床应用范围。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。