Discussion On The Correlation Between ODI Index And Openbite Malocclusion Under Angle's Classification

Objective: Through the measurement of the X-ray lateral cephalometric radiographs of patients with Class I,II,and III malocclusion and calculation the Overbite Depth Indicator(ODI),at the same time,statistics and analysis of factors affecting the angle of ODI index in the openbite and deep overbite of the Class III malocclusion.To explore the correlation between ODI index and openbite malocclusion,ODI index and deepbite malocclusion,in order to provide guidance for the diagnosis,evaluation and treatment of clinical openbite malocclusion cases.Methods: 1.Selected 74 anterior teeth open X-ray lateral cephalometric radiograph,which are divided into according to the relationship between the molars(25 in the Class I division),B(28 in the Class II division),and C(21 in the Class III division)three groups;all subjects were fixed,traced,measured and calculated ODI index.SPSS17.0 statistical analysis software was used,the ODI index values of the three groups were compared between the every two groups.When P<0.05,the difference was statistically significant.2.Seventy-five pieces of Angle Class III malocclusions with openbite or deepbite X-ray cephalometric radiograph were selected and divided into E(21 open and close groups,the same case data as C group)and D(anti-deepbite group)two groups;all subjects were fixed,traced,measured ?MP-AB and ?PP-FH angle values,and the ODI index was calculated.Using SPSS17.0 statistical analysis,the independent sample t-test and the comparison between groups were performed on the ODI index and ?MP-AB and ?PP-FH between the two groups.When P<0.05,the difference was statistically significant.Results: 1.The ODI index of the Class III openbite group is larger changed than that of the Class I and II openbite groups.2.There is a significant difference between the ODI index of the Class III openbite group and the ODI index of the Class I and II openbite groups(P<0.05).3.There was significant difference in ODI index and ?MP-AB between Group openbite and Deep-cover group of Class III(P<0.05),and there was no significant difference in ?PP-FH.(P>0.05).Conclusion: 1.The Overbite Depth Indicator(ODI)is less sensitive to Class III malocclusion than the Class I and II,and the reliability of the vertical anomaly of the malocclusion is assessed by a only ODI index.2.In the Class III anterior teeth opening and closing malformation,the vertical anomaly is related to ?MP-AB,but has no obvious relationship with the inclination of the palatal plane.