Cephalometric comparison of soft tissue changes after extraction and non-extraction orthodontic treatment

Objective: To compare changes occurring in the soft tissue profile with orthodontic treatment after extraction and non-extraction cases, and to determine soft tissue parameters that show significant correlations to understand the factors influencing the response to tooth movement. Methodology: Pre- and post-treatment lateral cephalographs of 16 subjects were assessed. For half of the patients (n=8), treatment included the extraction of 4 premolars, whereas the other half(n=8) were treated by the non-extraction approach.Soft tissue changes by treatment were analyzed and compared between both groups using the independent sample t-test to assess the degree of change with orthodontic treatment. Mean and S.D values before and after extraction and non-extraction treatment were also evaluated. Nasolabial angle, Labiomental angle, H angle, Lip chin submental angle, upper and lower sulcus depth to H line as well as upper and lower lip to E line were evaluated for study. Results: Although the premolar extraction group showed greater soft tissue changes with treatment, post-treatment comparisons showed that both extraction and non-extraction groups finished within the almost same soft tissue parameters. Conclusion: The effects of the two types of orthodontic treatment (i.e. extraction and non-extraction) on the facial soft tissues were very similar, indicating that treatment, involving the extraction of premolars, does not have a detrimental effect on facial aesthetics provided the decision to extract is on sound basis.