本文考虑了非对称三角形螺纹的螺距偏差和牙侧角偏差的各种组合对作用中径的共同影响，运用了包容图位移法，分析和推导出非对称螺纹作用中径的精确计算公式。

By the use of the displacing enveloping drawing method, a set of exact formulae for calculating the virtual pitch diameter is deduced and verified by measured data.

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大部分的宝宝长牙顺序都如此：先长两颗下门牙，然后再是两颗上门牙，接着长两侧及后面的牙。

Most babies get new teeth in this order: First the bottom two middle ones, then the top two middle ones, then the ones along the sides and back.

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为了基托均匀分散牙合力，这需要两侧上下颌尽可能多的人工牙在相互滑动的过程中有接触关系。

For the forces to be distributed throughout the denture bases, there need to be contacts between as many teeth as possible as they glide over each other, and on both sides of the arch.

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