颊近中的

In this research,MB2 root canals of the mesiobuccal root canal were found out by the rate of 35%and they were found obvious curve out by the rate of 91% in mesiodistal direction,83% in buccolingual direction.

本研究中有35%的标本探通了近颊根舌侧根管，其在近远中向、颊舌向出现明显弯曲的比例达91%、83%。

Majority of the four root canals of first maxillary molars showed curvatures at varing degrees in mesiodistal and buccolingual directions, and the second curvatures of them were different too.

上颌第一恒磨牙四个根管在近远中方向、颊舌方向均有不同程度的弯曲，其第二弯曲出现的情况也各不相同。

Methods Ninety-five lower first molars with buccolingual vertical fracture were separated and cut vertically along the fracture line to exposure the proximal and distal residual roots. After complete pulp canal therapy,the residual roots were covered with PFM post crowns.

方法选取95例颊舌方向纵折之下颌第一磨牙病例，完全纵剖牙冠及髓室底，获得独立的近远中残根，完整的根管治疗后，行桩核和烤瓷熔附金属全冠修复，3年后进行临床评价。

MB1 root canals of the mesiobuccal root canals in maxillary molars were found obvious curve out by the rate of 82.5% in mesiodistal direction,77.5% in buccoling

上颌第一恒磨牙四个根管在近远中方向、颊舌方向均有不同程度的弯曲，其第二弯曲出现的情况也各不相同。

Oral Surg,1971,32∶271-275［2］ Weine FS,Healy HJ,Gerstein H,et al.Canal configuration in the mesiobuccal root of the maxillary frist molar and its endodontic significance ［J］. Oral Surg Oral Med Oral Pathol,1969,28∶419-425［3］ Weller RN,Hartwell GR.

本研究通过对80例离体上颌第一磨牙行近远中方向，颊舌方向x 线投照，旨在近一步了结其根管的弯曲走向，弯曲程度，弯曲位置。X线片只能反应根管在一个平面上的走向、形态。

Methods 20 fresh extracted,same size in mesiodistal and height of cusp,1st up premolars were taken for this study.

磨除近远中邻面，使之近远中径为 4mm ，在颊牙尖釉质层下制备 4mm× 4mm× 3mm的洞型并随机分成两组。

After obtaining the nasorbital image fitting data as the reference to the simulation and mesiodistal to different angles of the post-core angle.

图像拟合之后获取颌骨形态参数，以此为参照模拟颊舌向及近远中向不同角度的桩核冠修复角度加力后寻求安全角度范围。

RESULTS: When torque force loads were applied, the peak values of VonMises stress on buccal side, lingual side and mesiodistal side of the implant neck were 0.624, 0.652, and 0.603 MPa, respectively, and the peak values of displacement were 0.066, 0.059 and 0.063 μm, respectively.

结果：在扭转力载荷作用下，种植体颈部颊侧、舌侧及近远中侧的VonMises应力峰值分别为0.624，0.652和0.603 MPa；位移峰值分别为0.066，0.059和0.063 μm。

In this study, the position of implant inclined to the lingual side slightly. When torque force was exerted on implants the lingual, buccal, and mesiodistal maximum Von-Mises stress were 0.65MPa, 0.624MPa and 0.603MPa, respectively.

由于本实验中种植体种植的部位略偏向舌侧，当种植体受到扭力作用的时候，其舌侧、颊侧及近远中侧的最大Von-Mises应力分别为0.65MPa、0.624MPa、0.603MPa。

Do you know, i need you to come back

你知道吗，我需要你回来

Yang yinshu、Wang xiangsheng、Li decang,The first discovery of haemaphysalis conicinna.

1〕 杨银书，王祥生，李德昌。安徽省首次发现嗜群血蜱。