A photographic analysis of soft tissue changes following Class II Division 1 malocclusion treatment with and without extraction

Background: There is a continuous debate on the issue of comparison between extraction and non-extraction treatment results in terms of subsequent soft tissue changes in Class II division 1 patients. So far, however, little attention has been paid to the photographic evaluation of treatment results. The aim of this study was to assess the impact of extraction and non-extraction treatment of Class II division 1 malocclusion on soft tissue profile by means of pre- and post- treatment photographs Methods: The pre- and post- treatment profile photographs of 41 borderline Class II division 1 malocclusion patients (ANB ≤5 degrees, and overjet ≤ 5 mm) were evaluated. The photographs were digitized into the computer and 19 angular measurements were evaluated. Paired t-tests and Independent-sample t-tests were performed to compare the pre- and post- treatment values between the extraction and non- extraction groups. The level of significance was set to be P < .05. Results: Significant differences between pre- and post- treatment values in extraction group existed for Z angle and N‑Sn‑Pog. In non-extraction group, significant differences were observed in N‑Pn‑Pog, G‑Sn‑Pog, N‑Sn‑Pog and N‑Sn‑B. When comparing the extraction and non-extraction groups before and after treatment, the results showed that the only significant difference was in PFH/AFH proportion. Conclusion: The results of this study revealed that for both extraction and non-extraction groups, there were straightening and improvement of soft tissue profile without significant impact on lips or nasolabial angle.