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Glabellar vertical line as a reference goal for anteroposterior maxillary position
Marcos J Carruitero1, Ximena M Ambrosio-Vallejos2, Carlos Flores-Mir3
1Antenor Orrego Private University (Trujillo, Peru).
Dental Press Journal of Orthodontics
|August 8, 2019
Summary
The glabellar vertical line (GVL) can serve as a simpler alternative to the goal anterior-limit line (GALL) for determining maxillary anteroposterior position. This method accurately predicts facial profile harmony when incisors are correctly positioned.
Area of Science:
- Orthodontics
- Cephalometrics
- Facial Aesthetics
Background:
- Accurate assessment of anteroposterior maxillary position is crucial for achieving facial harmony.
- Current methods may involve complex measurements, necessitating simpler alternatives.
Purpose of the Study:
- To evaluate the glabellar vertical line (GVL) as a reliable reference for determining the anteroposterior position of the maxilla.
- To compare the efficacy of GVL with the goal anterior-limit line (GALL) in orthodontic treatment planning.
Main Methods:
- A cross-sectional study involving 129 participants (mean age 20.21 years).
- Facial profile photographs were analyzed to measure distances from the incisor's most convex point (FA) to both GALL and GVL.
- Statistical analyses included Wilcoxon signed-ranks test, Spearman's correlation, and linear regression.
Main Results:
- A strong correlation (Spearman's rho=0.983, p<0.01) was found between FA-GALL and FA-GVL distances.
- The FA-GVL distance explained 95.84% (p<0.01) of the variation in FA-GALL distance.
- A predictive formula was derived: FA-GALL = 0.5 + 0.9 * (FA-GVL).
Conclusions:
- The glabellar vertical line (GVL) shows potential as a more user-friendly reference for maxillary anteroposterior positioning.
- GVL can be effectively used to guide treatment aiming to improve facial profile aesthetics, especially when maxillary incisors are appropriately positioned.
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