SKELETAL AND DENTAL CHANGES ASSOCIATED WITH THE TREATMENT OF DEEP BITE MALOCCLUSION

A retrospective study of 132 treated orthodontic cases presenting at l east 70% overbite was conducted using dental casts and lateral cephalo metric radiographs from before and after treatment. These were 61 Clas s 1, 27 Class II, Division 1, and 44 Class II, Division 2 malocclusion patients. Six different treatment modalities for the correction of th e deep bite were compared. On the basis of the analysis of cephalometr ic measurements, no statistically significant differences were observe d between the various treatment mechanics in the correction of the dee p bite. Only in the Class II, Division 2 sample, total anterior face h eight increased significantly (p < 0.01) with all treatment modalities . The data were then grouped according to Angle classification regardl ess of the type of mechanics used. Within each Angle class, the change s from before to after treatment were statistically significant for al most all of the cephalometric measurements. These significant changes were due to both anticipated growth and orthodontic treatment. The tre atment of overbite primarily affected the proclination of incisors and the extrusion of molars. Within each Angle classification, the patien ts were also separated according to whether the permanent teeth had be en extracted. The nonextraction group was compared with the extraction group for the changes in each cephalometric measurement. It was found that the extraction of teeth did have a significant effect on the cha nges observed with treatment in all the Angle classes but was more pro nounced in the Class I sample. The proclination of incisors was less a nd the mesial movement of molars was more in patients who were treated with the extraction of premolar teeth than those who were treated wit h the nonextraction procedures.