阻嚼运动各阶段中上颌总义齿基托应变的比较研究

Comparative study on the strain of mastication stages in maxillary complete denture base

目的：对咀嚼运动各阶段中平衡 与非平衡 时卜颌总义齿基托的张应变与压应变进行研究，对数据处理分析方法进行改进，对基托折断原因进行进一步的了解。方法：采用微机化动态电阻应变仪，测定应变值。并获取时间－应变曲线。结果：无论平衡 与非平衡 ，咀嚼的前期阶段的应变均大于后期阶段（Ｐ＜０．０１）。在平衡 时左右侧腭斜坡的张、压应变基本相等（Ｐ＜０．０５）。在左侧第一磨牙造成 干扰时，右侧腭斜坡为张应变，而左侧腭斜坡为压应变，腭基托中线前部的应变大于其他各部（Ｐ＜０．０１或０．０５）。结论：在义齿修复中平衡 是一个重要问题，是上颌总义齿基托折断最重要的原因之一。非平衡 时咀嚼花生米前期阶段腭中线前部为应变集中区，该区易发生折断。

Objective: To study the tension and compression strain of balanced and non balanced occlusion in the complete denture base in the mastication stages for improving the methods of dealing of data and further understanding on breaking reason. Methods: Measuring instruments with computer system was used to measure strain .The time-strain change curve was obtain. Results: The strain of the initial stages was larger than that of later stages in the balanced occlusion and non balanced occlusion (P<0.01). The strain was almost equal in the palate region of the left and right side in the balanced occlusion (P<0.05). The palate region of the right side was tension during premature contact of the left first molar. The palate region in the left side was compression strain. The strain in the palate middle line was larger than that of other section. Conclusions: The balanced occlusion was an important problem in the denture restoration. One of the most important reason was larger strain in the initial stages of the chewing peanuts of the non balanced occlusion.The strains were concentrated to the anterior section of the palate middle line,and were easily broken in this section.