Changes of Occlusal Plane in Growing Patients With Increased Vertical Dimension During Class II Correction by Using Cervical Headgear.

This retrospective research aimed to highlight the changes of occlusal plane in Class II hyperdivergent subjects that received cervical headgear treatment and compared them to untreated controls in order to evaluate the occlusal changes that might be connected to a potential mandibular rotation.The sample of this investigation was represented by 20 hyperdivergent Class II subjects (10 males, 10 females; mean age 8.54) corrected by using cervical headgear (treated group) and 21 Class II patients (11 males, 10 females; mean age 8.41) hyperdivergent who had no therapy (control group). Lateral head films were studied for all the patients before treatment (T1) and after therapy (T2) for both groups; cephalometric analysis was used in order to seek the modifications between time points and between groups.Means and standard deviation have been computed for both groups. In order to confront the modification between the time points within the same group the Wilcoxon test was applied. The Mann-Whitney U test was applied to confront the dissimilarities between groups at T2.As a result of the Class II correction by using the cervical headgear treatment the occlusal plane was lowered and flattened compared to T1 and to the control group; the upper molars showed extrusion to the palatal plane, there was a significant forward rotation of mandible and the vertical dimension was not significantly modified. Downward and backward displacement of the upper jaw occurred.