Comparison And Variation Of Various Vertical Cephalometric Parameters In Different Sagittal jaw dysplasias

Background: Most of the malocclusions that we often encounter are in sagittal direction, however most of the malocclusions that occur in sagittal dimensions are often accompanied by discrepancies in vertical dimensions. It is rare that we will find an anteroposterior discrepancy without the vertical dimension being affected. Numerous methods are available to diagnose the malocclusion in sagittal dimensions but there are considerably fewer methods available for vertical analysis. So multiple cephalometric analysis are used to diagnose vertical skeletal facial discrepancies associated with sagittal malocclusion. Aims and objectives: This study was aimed to identify and compare the various vertical cephalometric parameters that perform best for the identification of vertical skeletal pattern in different sagittal dysplasias. Materials and Methods: A total sample of 60 subjects with 20 subjects in each Class I, Class II and Class III skeletal groups were included. The age groups 18–30 years were included with male and female subjects. The vertical cephalometric parameters were measured and variation was studied and comparison was done in each group of sagittal dysplasia, and mean values, SDs, and P values were calculated by applying descriptive statistics along with Analysis of variance (ANOVA) for comparison among three skeletal groups by using Statistical software SPSS (version 20.0) and Microsoft Excel. The level of significance was set at p value < 0.05. Results: The descriptive statistical analysis was first done to find out the means of each parameter along with the standard deviation in each group whether increased or decreased from the mean average value. After that comparison was done for each parameter among the three groups to find out any statistically significant difference by using Analysis of variance (ANOVA) for intergroup comparison. On doing the intergroup comparison statistically significant difference was found in saddle angle amongst three groups with p value less < 0.026 which was considered statistically significant. Statistically significant differences were also found between symphyseal angle and symphyseal H/A with p value < 0.012 and < 0.006 respectively which was considered statistically significant, however statistically no significant differences were found in other parameters on doing intergroup comparison. Conclusions: Different parameters were used in this study to identify vertical disharmony in different sagittal classes. In skeletal class II subjects the condyle is posteriorly placed in glenoid fossa and mandible is retrognathic with respect to cranial base due to large saddle angle and articular angle and mandibular plane to true horizontal plane angulation shows vertical growth direction. Symphyseal angle is obtuse in class II subjects with wide and short symphysis in both class I and Class II subjects. In class III patients lower gonial angle is increased with vertical growth direction, there is increased ramal length and lower facial height from ANS to Gn is also increased. Vertical soft tissue parameters i.e.; (vertical lip: chin ratio) are within normal range in all the three classes.