It should by now be obvious that this seal is more easily obtained in the upper denture than the lower, because of the greater movements of the lower border tissues, especially lingually.

• 至此，很显然，由于下颌义齿边缘尤其是舌侧软组织运动活跃，上颌义齿获得良好边缘封闭要较下颌容易得多。