Short-term effects of systematic premolar extraction on lip profile, vertical dimension and cephalometric parameters in borderline patients for extraction therapy--a retrospective cohort study.
OBJECTIVE
The belief of many orthodontists that premolar extraction therapy leads to a loss of vertical dimension and an aggravated facial profile often predetermines a non-extraction approach. We investigated the short-term effects of systematic premolar extraction in borderline cases for extraction therapy on dentofacial parameters, especially vertical dimension and facial profile.


METHODS
Of 50 juvenile borderline cases for extraction treatment with a distinct sagittal overjet of 6-9 mm and dental crowding of >6 mm, 25 had all first premolars extracted, whereas the 25 control patients received non-extraction orthodontic treatment with corresponding fixed and removable appliances. Patient selection by multivariate cluster analysis ensured homogeneity at baseline regarding dentoskeletal parameters. Parameter changes were determined with radiographic cephalograms and compared between the extraction and non-extraction group.


RESULTS
The systematic extraction of premolars in borderline patients with a distinct sagittal overjet and crowding did not significantly influence sagittal or vertical skeletal dimension, while leading to a slightly more concave lip profile due to incisor retraction compared to the non-extraction control group.


CONCLUSIONS
The influence of premolar extractions on facial profile is often overestimated, since only slight changes in lip profile are to be expected. In integrated treatment planning, the extraction decision should not be primarily based on concerns about the aggravation of facial profile and loss of vertical dimension.
The decision, whether to extract healthy premolars in borderline patients for extraction therapy, is difficult to make. Our study clarifies the repercussions on cephalometric dentofacial parameters, facilitating future orthodontic extraction decisions.
Department of Orthodontics, University Medical Centre of Regensburg, Franz-Josef-Strauß-Allee 11, 93053, Regensburg, Germany. christian.kirschneck@ukr.de.
Christian
http://orcid.org/0000-0001-9473-8724
C
Kirschneck
Department of Orthodontics, University Medical Centre of Regensburg, Franz-Josef-Strauß-Allee 11, 93053, Regensburg, Germany.
Peter
P
Proff
Department of Orthodontics, University Medical Centre of Regensburg, Franz-Josef-Strauß-Allee 11, 93053, Regensburg, Germany.
Claudia
C
Reicheneder
Department of Orthodontics, University of Muenster, Waldeyerstraße 30, 48149, Muenster, Germany.
Carsten
C
Lippold
D000293:Adolescent; D001641:Bicuspid; D002508:Cephalometry; D002648:Child; D005260:Female; D006801:Humans; D008046:Lip; D008297:Male; D012189:Retrospective Studies; D014081:Tooth Extraction; D014716:Vertical Dimension
Cephalometry/methods; Cohort studies; Face/anatomy and histology; Orthodontics; Tooth extraction/adverse effects