<abstract xmlns="http://www.w3.org/1999/xhtml">

<italic>Aim</italic>: This retrospective study was designed to compare the responses of the upper and lower lip curves in young growing males, to orthodontic treatment involving either four premolar extractions or the holding of the E-spaces without premolar extractions.
<italic>Method</italic>: Pre- and post-treatment lateral cephalograms of 67 premolar extraction and 30 nonextraction patients were assessed. The results were subjected to analysis of variance to search for statistically significant differences amongst the pretreatment variables and changes in depths of lip curves. Pearson’s correlation coefficients were also calculated and stepwise regression analysis undertaken.
<italic>Results</italic>: A wide range of lip curve behaviour was seen in individual patients within all groups. No significant differences were found in the change in depth of lip curve amongst the various extraction and nonextraction groups. The inherent morphology of the soft tissues appeared to be the greatest determinant of lip curve behaviour with treatment.
<italic>Conclusions</italic>: It would appear that neither premolar extraction nor nonextraction treatment, if based on appropriate diagnostic criteria and followed with competent clinical management, will necessarily lead to direct effects on lip curvature.
</abstract>

Aim: This retrospective study was designed to compare the responses of the upper and lower lip curves in young growing males, to orthodontic treatment involving either four premolar extractions or the holding of the E-spaces without premolar extractions.
Method: Pre- and post-treatment lateral cephalograms of 67 premolar extraction and 30 nonextraction patients were assessed. The results were subjected to analysis of variance to search for statistically significant differences amongst the pretreatment variables and changes in depths of lip curves. Pearson’s correlation coefficients were also calculated and stepwise regression analysis undertaken.
Results: A wide range of lip curve behaviour was seen in individual patients within all groups. No significant differences were found in the change in depth of lip curve amongst the various extraction and nonextraction groups. The inherent morphology of the soft tissues appeared to be the greatest determinant of lip curve behaviour with treatment.
Conclusions: It would appear that neither premolar extraction nor nonextraction treatment, if based on appropriate diagnostic criteria and followed with competent clinical management, will necessarily lead to direct effects on lip curvature.

Lip curve changes in males with premolar extraction or nonextraction treatment

Australasian Orthodontic Journal

This work is licensed under the Creative Commons Attribution 4.0 International License.

{"article-title":"Lip curve changes in males with premolar extraction or nonextraction treatment"}

Aim: This retrospective study was designed to compare the responses of the upper and lower lip curves in young growing males, to orthodontic treatment...

Lip curve changes in males with premolar extraction or nonextraction treatment

Published Online: Dec 13, 2023

Page range: 71 - 86

Received: Jan 01, 2004

Accepted: Sep 01, 2004

DOI: https://doi.org/10.2478/aoj-2004-0010

© 2004 Pei-Ti Lin et al., published by Sciendo

This work is licensed under the Creative Commons Attribution 4.0 International License.