切牙

Results:The treatment of 52 tooth-veneers had been finished within one day.After six months to one year and a half follow-up,one case veneer lost after two months,two cases occured hypersensitiveness of dentin and one case veneer fractured in incisal edge,the others were kept normally without any changes in shades and contour.

结果：52颗患牙均一次完成治疗，随访6个月～1.5 a.1颗牙2个月后脱落重贴；2颗在切端有牙本质过敏现象，经脱敏治疗恢复正常；1颗切端折裂，以光固化复合树脂修复；其余均正常使用，色泽、形态均无变化。

The three groups were loaded and analyzed under the same loading according to the mean value of the bite force of incisors. RESULTS:(1)The maximum stress of dentin in group A was twice higher than that in group B. The maximum primary stress, minimum primary stress and maximum shear stress of group A were respectively 236.35, 228.83 and 218.05 percent of those in group B. The difference of maximum stress values of group B and group C was neglectable.(2) The maximum stress distribution of dentin in group A and group B was quite different (the stress was concentrated in labial and lingual side of the cervical dentin in group A, otherwise in group B it was concentrated in the area around the alveolar and the labial and lingual side of the dentin which was opposite to the tip of the cast metal post and core). The maximum stress distribution of dentin in group A and group B was almost the same.

结果：(1)从牙本质的应力大小来看，A组中牙本质最大应力值比B组中牙本质最大应力值增大了1倍以上（最大主应力、最小主应力和最大剪切应力A组分别是B组的236.35%、228.83%和218.05%），而B组与C组的牙本质最大应力值相差极小；(2)从牙本质的应力分布位置来看，A组与B组的牙本质最大应力分布位置相差甚远（A组主要集中在牙颈部唇舌侧肩台部的牙本质上，B组主要集中于牙槽嵴顶附近及铸造桩核尾端相对应的唇舌侧的牙本质上），而B组与C组的牙本质最大应力分布几乎在同一位置。

The experiment of closing alveolar cleft by DO technique was successful. It suggests a new method to treat alveolar cleft, without alveolar bone grafting and donor area morbidities. Thus, long-term studies are very necessary to try to introduce it into clinic.

本实验采用DO关闭牙槽裂隙的动物实验研究是成功的，同时，也开辟了治疗牙槽突裂的新思路，可以避免传统牙槽裂植骨术需从患者供骨区切骨的组织损伤和痛苦；且手术操作较简单，可在局麻下完成。

At the end of the experiment, the first incisors of 1 , II , III group were pulled out respectively, some were decalcified for SEM and TEM examinants and HYP analyses; the others were not decalcified for SEM examinants.

实验结束时，取Ⅰ、Ⅱ、Ⅲ组的每只羊的第一对切齿，不脱钙扫描电镜观察牙釉质与牙基质的结构情况；脱钙后扫描和透射电镜观察牙基质结构，化学分析法分析牙基质中羟脯氨酸的含量。

This situation occurred in the central incisors.

这种情况多发生在上中切牙。

More than a month on the long under the two central incisors.

5个多月就长了2个下中切牙。

They have two pairs in the front of their mouths and these incisors never stop growing and thus must be regularly worn down.

他们有两对在前面的嘴巴和这些切牙从未停止增长，因此必须定期拖垮。

Objective To study the feature of the incisor nerve canal and its relation to the mandibular canal and mental canal so as to offer a reliable anatomical data for the distric operation.

目的 研究国人切牙神经管的位置及下颌管、颏管的关系，为临床手术提供解剖学数据。

Results: The first 3－D finite element model of the maxillary incisors,which including orthodontic appliances and pulp cavity,was successfully constructed.

结果：建立了首个包含髓腔和矫治器系统的左侧上颌切牙段三维有限元模型，形态逼真，精度高。

Sheet-fed flat die-cutting relies on the syndiospecific side of the former gauges, mechanical positioning, and the development of an on-line die-cutting relies on the business card printing and membership card making tagging, and do not pick out the paper teeth, in order to achieve wheel system transformation cards and membership cards of consecutive paper making unit to die-cutting-intermittent motion changes, often feeding Assembly set up an eccentric mechanism djustable.

单张纸平压平模切是依靠前规、侧规机械定位的，而联线平压平模切是依靠制卡和会员卡制作标记定位的、且没有叼纸牙排，为了实现轮转制卡和会员卡制作单元纸张的连续传到模切工位的间歇运动的转变，通常在给纸装里设置一个可调的偏心机构。

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。