电测法测量上颌总义齿基托中线区的应变变化规律

目的观察上颌总义齿基托中线区在咬合平衡及非平衡时的应变变化规律。方法采用口外电测应变法，在固定载荷下记录咬合干扰前后义齿基托中线上各点应变值的变化，并进行统计分析。结果咬合平衡及非平衡时最小应变值均位于基托中部附近，前部最大；非平衡胎时应变值明显大于平衡胎时的应变值。两组数据之间呈高度正相关。结论上颌总义齿基托由前向后应力逐渐减弱，非平衡殆时整个基托应力、应变的重新分布呈不均匀性。

Measurement of strain distribution on base plate of maxillary complete denture with static resistance gage

Objective To investigate the strain distribution along the middle line on base plate of maxillary complete denture under balanced and unbalanced occlusion. Methods The static resistance strain gage instrumentation was employed. The measurement of strain value under a static load before and after the occlusal interference was carried out and analyzed statistically. Results The strain value at front part of the base plate was the largest under the condition with or without occlusal interference. The data on unbalanced occlusion were larger than those on balanced condition, and a statistically significant positive correlation existed between the two data groups. Conclusion The front part of base plate on maxillary complete denture was easy to fracture. The strain on the base plate redistributed unevenly with the occlusal interference, which increased the incidence of midline fracture.