Clinical Study In Skeletal Class â…¡ Malocclusions

ObjectiveThe aims of this study were1) to evaluate the amount, direction of the soft tissue changes associated with simultaneous skeletal changes in serious skeletal Class II malocclusion patients treated with orthodontic and surgical treatments.2) to analyze the changes in mild and moderate skeletal Class II malocclusion adults treated with 4 first premolars extraction orthodontic treatment.Materials and Methods1) The 18 cases with serious skeletal Class II malocclusion treated with orthodontic and surgical treatments concluding 5 male and 13 female from 19 to 41 years old were chosen.Each patient was taken standardized lateral cephalograms 1 month before and after treatment. A total of 14 hard and soft tissue landmarks were evaluated in both horizontal and vertical directions.2) Thirty Class II malocclusion patients treated with 4 first premolars extraction orthodontic treatment were chosen and cephalometric analysis was performed .3) Statistical analysis was performed using Spss 10.0 software.Results1) Soft tissue changes of patients with skeletal Class II malocclusion after orthodontic and surgical treatments:?Soft and hard tissue changes of angles and lines: With hard tissue measurements, SNA angle, ANB angle and NAPg angle were reduced significantly(P<0.01) after treatment .The distance of UI-N and A-N were reduced (P<0.05), too. On the other hand, Pg-N distance was increased significantly(P<0.01).And SNB angle , UI- LI angle and B-N distance were increased (P<0.05), too. With soft tissue measurements, the nasolabial angle and Li-EP distance were increased significantly(jP<0.01). B'-EP distance was increased (P<0.05), too. But Ls-EP distance was reduced significantly (P<0.01) after treatment ,and the similar change to Stms-Stmi distance and Stms-UI distance(P<0.05).(2) In the horizontal direction, all the soft and hard tissue maxillary landmarks movedposterior and all the mandibular landmarks moved anterior. With hard tissue landmarks.allchanges had significant difference(P<0.05). With soft tissue landmarks,the changes of Lsand Stms moved posterior significantly(P<0.01) .And the change of A' had significant difference (P<0.05),too.Otherwise, Pg'moved anterior(P<0.05).(3) In the vertical direction,all the soft and hard tissue biomaxillary landmarks moved upward.The changes of all the hard tissue landmarks had significant difference(P<0.01). With soft tissue landmarks,the changes of Stms, Pg',Stmi,Li and B' had significant difference (P<0.05).2) Soft and hard tissue changes of patients with skeletal Class II malocclusion after orthodontic treatment with extraction:(1) Hard tissue changes after treatment: Overbite, overjet,UI-SN distance and LI-MP angle were reduced significantly (P<0.01) . ANB angle, UI-N A angle , UI-NA distance, LI-NB distance and LI-MP distance were reduced (P<0.05) ,too.But UI- LI angle was increased (P<0.01).(2) Soft tissue changes after treatment: The nasolabial angle , upper and lower lip angle were increased significantly(P<0.01). Upper lip angle and the protrusion of the upper lip were reduced significantly(P<0.01).Upper lip thickness was increased (P<0.05) . Lower lip angle was increased(P<0.05). And the protrusion of the lower lip was reduced (P<0.05).IVConclusions1) The combined orthodontic and surgical treatment was an effective way to treat serious skeletal Class II malocclusion.All the patients regained satisfactory face appearance and profile.2) The orthodontic treatment mainly affected the position of upper and lower teeth.After treatment,the molar relationship was changed from II to I and the patients' profile was much improved.