Class II division 1 malocclusion treatment with extraction of maxillary first permanent molars: cephalometric evaluation of treatment and post-treatment changes

Abstract Objective To investigate the cephalometric outcome and post-treatment changes following the orthodontic treatment involving the extraction of maxillary first molars in patients presenting with a Class II division 1 malocclusion. Methods A retrospective longitudinal study was conducted involving 83 patients treated by fixed appliances and the extraction of 16 and 26. The mean age at commencement was 13.2 ± 1.5 years. Lateral cephalograms were available pre-treatment (T1), immediately post-treatment (T2), and at 2.6 years post-treatment (T3). The sample was divided into hypodivergent (n = 18), normodivergent (n = 17), and hyperdivergent (n = 48) facial types. Mean increments, standard deviations, and 95% confidence intervals were calculated for T2–T1 and T3–T2. Increments were tested using paired-samples t-tests, and variables between groups by applying ANOVA followed by Tukey’s post hoc test. Linear regression was used to examine the effect of facial type, age, and gender. Results Significant changes occurred during treatment for most cephalometric variables. Post-treatment, the growth pattern showed a tendency to return to the original form. Facial type had only a minor influence on cephalometric increments during and after treatment. Conclusions Post-treatment skeletal, soft tissue, and dentoalveolar changes were limited. Facial type had only a minor influence during and after treatment and care must be taken to control lower incisor inclination.