上颌骨后的

Van Beek's activator appliance could restrict the growth of maxilla and stimulate the growth of mandible in horizontal direction and control jaws posteroinferior rotation , lower front teeth and elongate mandibular molar in vertical direction.

Beek功能矫正器能在水平方向产生抑制上颌骨生长，刺激下颌骨生长；在垂直方向控制上下颌骨后下旋转，压低上下前牙及伸长下磨牙的效果。

Methods:Three dimensional finite element model of the edentulous maxilla with unilateral maxillary defect was build.

目前应用种植体技术是解决无牙颌上颌骨缺损及缺失后咀嚼功能重建的最有效途径[2～5]。

Sanctus. Mandibular fenestra expanded anteriorly. Maxilla protruding more anteriorly than in C. sanctus. Wing claw less developed. Sternum relatively elongate with a "V"-shaped anterior notch. Sternum with a pair of short posterior proceses. Tarsometatarsus relatively short. Pygostyle expanded distally.

上颌骨较圣贤孔子鸟向前突出，指骨爪没有圣贤孔子鸟那样伸长、强壮，胸骨比较拉长，前喙中央有一凹刻构造成"V"字形，同时胸骨两侧有一对短的后侧突，跗蹠骨较圣贤孔子鸟短，以及尾综合、骨末端膨大。

The changes have important effect on the stability of the treatment and the function of mastication.

通过牵引成骨和正畸联合矫治严重上颌后缩后，上颌骨的前移和牙齿的移动必然使上下牙的排列和咬合发生变化，而这种变化对疗效的稳定性和患者的咀嚼功能的恢复有着重要影响。

Results The position of the maxilla after orthopedics was significantly advanced (P .001), but there was still difference from normal values.

结果治疗后上颌骨的位置前移变化有显著性(P＜0.01)，但与正常值之问也存在一些差异。

Objective To study the changes in maxilla,mandible and SN after orthodontic treatment with four premolars extracted in bimaxillary protrusion in adolescents and provide clinical useful data for predicting curative effect after orthodontic treatment.

目的：研究青少年双颌前突患者拔牙矫治前后上颌骨、下颌骨及前颅底的变化，为临床预测矫治后疗效提供临床依据。

Objective To study the changes in maxilla,mandible and SN after orthodontic treatment with four pre－molars extracted in bimaxillary protrusion in adolescents and provide clinical useful data for predicting curative ef－fect after orthodontic treatment.

目的：研究青少年双颌前突患者拔牙矫治前后上颌骨、下颌骨及前颅底的变化，为临床预测矫治后疗效提供临床依据。

The edgewise technique was used to align and level the upper and lower arches gradually and upright the lower incisors. Then, modified LeFort Ⅰ osteotomy was operated with 4 cases pterygomaxillary disjunction and the other 2 cases not. The maxillas were not moved during the operation and sutured mucoperiosteum at the same place. After 3-5 days latency period, elastic distraction about 700g/side and increasing to 1400g/side gradually, was started with two cases which the maxillas were not cut off totally.

术后经过3—5天的延迟期即开始牵引，2例行不完全截开术者，采用弹性牵引，力量从700g／侧逐渐增加至1500g／侧；4例行完全骨截开术者，首先采用刚性牵引和口外牵引钩，每天缩短牵引钢丝1mm，2例直接达到矫治要求，其余2例达到浅覆盖后，截去口外牵引钩，换弹性牵引和口内牵引钩继续前牵上颌骨。

Sanctus. Mandibular fenestra expanded anteriorly. Maxilla protruding more anteriorly than in C. sanctus. Wing claw less developed. Sternum relatively elongate with a "V"-shaped anterior notch. Sternum with a pair of short posterior proceses. Tarsometatarsus relatively short. Pygostyle expanded distally.

上颌骨较圣贤孔子鸟向前突出，指骨爪没有圣贤孔子鸟那样伸长、强壮，胸骨比较拉长，前喙中央有一凹刻构造成&V&字形，同时胸骨两侧有一对短的后侧突，跗蹠骨较圣贤孔子鸟短，以及尾综合、骨末端膨大。

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。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。