Soft tissue facial profile changes after orthodontic treatment with or without tooth extractions in Class I malocclusion patients: A comparative study

Abstract

Objective: To analyze the soft tissue facial profile changes in Class I malocclusion patients after orthodontic treatment with or without tooth extraction. Methods: Forty lateral cephalograms of 20 individuals with Angle Class I malocclusion submitted to orthodontic treatment were included in this study. The individuals were divided in two groups: no tooth extraction (Group A) and extraction of four first premolars (Group B). Cephalometric measurements related to the soft tissue facial profile (Nasolabial Angle, Mentolabial Angle, Interlabial Angle, Facial Convexity Angle, Total Facial Convexity Angle, Lower Face Angle, MAFH/LAFH Proportion, Lower Face Vertical Proportion, H.NB Angle, Ricketts E Line) were collected in two stages (pre-treatment and post-treatment). The Student T, Wilcoxon and Mann-Whitney tests analyzed the results. The significance level was 5%. Results: Among the cephalometric variables evaluated, only the measurements Interlabial Angle and H.NB Angle showed statistically significant changes during treatment. Increase was observed in the Interlabial Angle and decrease in H.NB Angle in both groups, resulting in a less convex facial profile with lip retraction. Conclusion: The findings suggest that changes in the soft tissue facial profile are similar in Class I patients treated with or without tooth extraction.

Keywords

• Cephalometrics
• Tooth extraction
• Orthodontics
• Fixed appliance