不同力牙尖交错位咬合接触的计算机图像分析

Study on the occlusal contacts in the intercuspal position under different bite force with computer-aided video analysis system

目的：研究不同 力下牙尖交错位咬合接触的变化规律。方法：用硅橡胶印模材料，采集２１名正常 青年人轻度 力、中等 力及紧咬３种条件下的咬合接触记录模型，用计算机图像分析系统进行测量。结果：相同 力下的咬合接触记录具有良好的重复性（配对ｔ检验，Ｐ＞０．５）。 力增加，前牙区颌间距离减小，后牙区咬合接触数目增多。中等 力时，咬合接触主要集中在２０μｍ以下。结论： 力增大，接触数目增多， 的稳定性增加。应用计算机图像分析系统进行咬合接触定量分析时，应采用中等 力下咬合接触记录模型，以２０μｍ颌间距离作为接触标准。

To investigate the change of the occlusal contacts with the change of bite force.Meth- ods: Models of occlusal contacts recorded with silicon impressions from 21 subjects with nomal occlusion at light, medium and hard bite force were measured with a computer-aided video analysis system. Results:In the same individual, there was no difference of occlusal contacts at the same pressure (matched-pair t test, P> 0.5). with bite force increasing, the interocclusal distance in the anteriopr segment shortened and the number of occlusal contact in the posterior segment increased, but the position did not change. Under medium pressure, the occlusal contacts mainly distributed under 20 pm interocclusal distance. Conclusion: The stability of occlusion is improved by and adapted to the strengthening of bite force. Occlusal contacts should be registrated under medium bite force and 20 μm interocclusal distance should be regarded as contact.