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Investigating the relationship between the occlusal plane and the tragus-ala line in patients with different jaw
Hadi Ranjzad1, Farzaneh Ostovarrad2, Elnaz Saidi3
1Assistant Professor, Department of Prosthodontics, School of Dentistry, Gilan University of MedicalSciences, Rasht, Iran.
Background:
This study investigated the relationship between the occlusal plane and the ala-tragus lines (ATL) for restoring the upper and lower jaws and analyzed the ATL in different jaw classifications.
Material And Methods:
This analytical cross-sectional study included lateral cephalometric radiographs of 172 patients with teeth in a normal position. The three ATLs and the occlusal plane were delineated, and jaw classification was determined using Waits and Steiner analysis.
Results:
For jaw classes 1 and 2, the parallelism between the lower ATL and the occlusal plane was not statistically significant. However, for class 3 patients, significant parallelism was observed between the lower ATL and the occlusal plane, regardless of the maxillary classification. In the gender-based analysis, the parallelism between the occlusal plane and the lower ATL was significant for women. In the age-based analysis, the parallelism was significant in the age group of 15-21 years.
Conclusions:
These findings suggest that the lower ATL can be a reliable reference for determining the occlusal plane. The study also highlights that age and gender are important factors influencing the determination of the occlusal plane using the ATL. Key words:Occlusal plan, ala-tragus line, cephalometric radiograph.
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