The Static and Dynamic NLA in Relation to Malocclusion

Autores/as

  • Kasem Ahmed Abeas University of Babylon/ college of dentistry

DOI:

https://doi.org/10.5195/d3000.2026.1618

Palabras clave:

Orthodontics, Malocclusion, Cephalometric analysis

Resumen

The naso-labial angle (NLA) is one of the key soft tissue factors to be considered in an orthodontic diagnosis as guidance for the aesthetics of the lip, nose, and so the facial profile. The objective of this study was to assess and compare, the static and dynamic NLA within and between class I and II malocclusions for male subjects using lateral photographic view of the face. Following the study criteria; 100 dental students were collected from faculty of dentistry/ university of Babylon with mean age was 22.8 years. Of these, 60 were class I malocclusion and 40 were class II malocclusion according to angle classification. For each participant in either group, a lateral photographic view was taken in upright head posture using Canon digital camera. Subjects were photographed in 2 frameworks: 1st in the static relation and 2nd in the dynamic relation. SPSS version 26 was used for statistical data analyses using Wilcoxon and Mann-Whitney test. Utilizing an AutoCAD 2024, the NLA was recorded by measuring the angle formed by connecting the two lines passing through subnasale-columella nasi and subnasale-labrale superior points. The NLA values are more and significantly higher in static than in dynamic posture for the 2 groups (93°/82°; 80°/69°) respectively. Moreover, the NLA showed a significant increase in their static and dynamic values in class I compared with class II malocclusion, (P < 0.001). These results signify the impact of malocclusion on the NLA and the role of soft tissue dynamics on facial profile compensation. The NLA display a great variation across malocclusions and its posture as well. However, the dynamic NLA is much less than static angle that signify the compensatory mechanism of facial tissues in profile modification which is an important feature to consider in orthodontic diagnosis.

Citas

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Publicado

2026-10-06

Número

Vol. 14 Núm. 3 (2026): Fall

Sección

Development of Craniofacial Structures

Licencia

Derechos de autor 2026 Kasem Ahmed Abeas

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