Quantifying changes in incisor inclination before and after orthodontic treatment in class I, II, and III malocclusions

BACKGROUND This study was designed to determine if orthodontic treatment significantly changes the upper incisor position in Class I, II, and III dental and skeletal malocclusions. METHODS Ninety nonextraction-treated patients were included in this retrospective cohort study and divided into three groups: Class I, Class II, and Class III. All cephalometric measurements (ANB, Wits, U1-PP, U1-SN, U1-NA, U1 perpendicular to FH and U1-L1) were taken using the Dolphin Management and Imaging Software, Version 05.05.5070.221436 (United States and Canada). RESULTS The posttreatment values of ANB, Wits appraisal, U1-NA mm, U1-FH mm, IMPA and U1-L1° are statistically significant (P < 0.05) among the Class I, II, and III when compared with the normal values. Also ANB° changes after orthodontic treatment in Class I, II, and III were statistically significant with the greater changes in Class III malocclusion. CONCLUSIONS There is a significant amount of dento-alveolar compensation for the maxillary incisors not only in patients with Class II and III but also in Class I malocclusions that underwent nonextraction treatments.