The Research Of The Relativity Between The Orthodontic Extraction And KIM EI

Objective: 1. To explore the significance of KIM EI the clinic application, it was compared the relativity between the extraction index (EI) and practical extraction in the group of teenagers and adults when treating the cases of class I ,class II, and classIII malocclusion, in order to find out the differences between teenagers and adults, slight congestion group and congestion group.2.To investigate the significance of improved EI in clinic application, it was established the improved EI formula by putting the congestion degree into KIM EI formula.Methods: l.Data were obtained from 429 cases after successful treatment with malocclusion. Dividing the patients into adults group(over 18) and teenager group(under 18) according to age division; Categorizing the patients into class I , class II ,and classIII by Angle malocclusion method; furthermore, dividing each group into the light congestion group and congestion group. Analyzing the function of congestion factor between the groups, and doing the retrospective test of KIM EI at the same time.2.Taking the congestion degree into KIM EI predicting formula, it was done the retrospective test of EI relativity in each group using the improved EI prediction formula.Results: 1. Precision predicting to all exponent is 73.21% using KIM EI. In the EIpredicting extraction group, There is no different significance of the practical extraction between congestion group and slight congestion group(p>0.05); In the El predicting non-extraction group, There is significant difference of the practical extraction between congestion group and slight congestion group(p<0.05);In the age dividing group, the total unanimous rate is 71.28% in teenagers group. In the El predicting extraction and non-extraction group, There is no different significance of the practical extraction between congestion group and slight congestion group(p>0.05); the total unanimous rate is 75% in adults group. In the El predicting non-extraction group, There is significant difference of the practical extraction between congestion group and slight congestion group(p<0.05). According to the malocclusion type classification, the total unanimous rate is 71.95% in Angle I cases , In the El predicting non-extraction group, There is significant difference of the practical extraction between congestion group and slight congestion group(p<0.05). The total unanimous rate is 71.62% in Angle II cases, In the El predicting non-extraction group, there is significant difference of the practical extraction between congestion group and slight congestion group(p<0.05).2. Precision predicting to all exponent is 79.21% using improved El.In the El predicting extraction and non-extraction group, There is no different significance of the practical extraction between congestion group and slight congestion group(p>0.05). In the age dividing group, the total unanimous rate is 74.19% in teenagers group,83.47% in adults group. According to the malocclusion type classification, the total unanimous rate is 81.07% in Angle I cases,82.24% in Angle II cases, There is no different significance of the practical extraction between congestion group and slight congestion group(p> 0.05) in each group.Conclusion: l.KJM El have some guidances in the strategy of malocclusion design whether in different age groups or in different Angel classes. However, the higher rate in slight congestion group than in congestion group suggests that KIM El...