BACKGROUND: The potential for premolar extractions to produce changes in the soft tissue profile after orthodontic treatment is controversial. AIM: To evaluate the soft tissue changes associated with four first premolar extractions in adult females of South Indian ethnicity. METHOD: Pre- and post-treatment lateral cephalometric radiographs of 30 adult female patients of South Indian ethnicity with bimaxillary dentoalveolar protrusion, requiring premolar extractions as a part of their orthodontic treatment, were used. The radiographs were traced and changes in three angular and 12 linear measurements measured relative to the perpendicular to the horizontal reference line, 7 degrees down from S-N through S. Correlation coefficients between the changes in the upper and lower incisors and the lip measurements were calculated. RESULTS: All linear and angular measurements, except for changes in upper and lower lip thickness, B' point and the anterior point on the lower lip, showed statistically significant (p < 0.05) changes with treatment. A significant negative correlation was found between upper incisor change and nasolabial angle change and a significant positive correlation was found between upper incisor change and retraction of the most anterior point on the upper lip. CONCLUSION: Extraction of the four first premolars followed by the retraction of incisors reduced the dental and soft tissue protrusion found in adult South Indian females with bimaxillary dentoalveolar protrusion.
BACKGROUND: The potential for premolar extractions to produce changes in the soft tissue profile after orthodontic treatment is controversial. AIM: To evaluate the soft tissue changes associated with four first premolar extractions in adult females of South Indian ethnicity. METHOD: Pre- and post-treatment lateral cephalometric radiographs of 30 adult female patients of South Indian ethnicity with bimaxillary dentoalveolar protrusion, requiring premolar extractions as a part of their orthodontic treatment, were used. The radiographs were traced and changes in three angular and 12 linear measurements measured relative to the perpendicular to the horizontal reference line, 7 degrees down from S-N through S. Correlation coefficients between the changes in the upper and lower incisors and the lip measurements were calculated. RESULTS: All linear and angular measurements, except for changes in upper and lower lip thickness, B' point and the anterior point on the lower lip, showed statistically significant (p < 0.05) changes with treatment. A significant negative correlation was found between upper incisor change and nasolabial angle change and a significant positive correlation was found between upper incisor change and retraction of the most anterior point on the upper lip. CONCLUSION: Extraction of the four first premolars followed by the retraction of incisors reduced the dental and soft tissue protrusion found in adult South Indian females with bimaxillary dentoalveolar protrusion.