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Evaluating the Relation of Posterior Occlusal Plane to Ala-Tragal Line According to Age and Sex; [Оценка Отношения Задней Окклюзионной Плоскости К Алатрагальной Линии В Зависимости От Возраста И Пола] Publisher Pubmed



Ghodsi S1 ; Omrani SS2 ; Mogharrabi S2 ; Valizadeh S3
Authors
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Authors Affiliations
  1. 1. Dental Research Center, Dentistry Research Institute, Department of Prosthodontics, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran
  2. 2. Department of Prosthodontics, School of Dentistry, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
  3. 3. Restorative Dentistry Department, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran

Source: Folia Medica Published:2022


Abstract

Introduction: Occlusal plane orientation affects the esthetic, function, and success of removable or fixed prostheses. The most prevalent index for determination of this plane is the ala-tragus line while there are controversies in the exact location of tragus reference point. Aims: This study aimed to determine the best point on tragus as the posterior reference of ala-tragal line in relation to occlusal plane according to age and sex. Materials and methods: The study included 136 participants of both sexes who were randomly divided into three age groups: 20-35, 36-50, and older than 50. Fox plane was stabilized on incisal edge-occlusal table of maxillary teeth. A lateral photograph was obtained from each participant sitting in predetermined standard position. Using Auto-Cad software, three lines were traced from nasal ala base to superior, middle, and inferior borders of the tragus, and evaluated for being parallel to occlusal plane. Results: The coordination between occlusal plane and ala was 20.5% for superior, 35.6% for middle, and 43.9% for inferior border of tragus. There was a significant difference in the relationship between sex and plane position (p=0.003), while the relationship between age and plane could not reach statistical significance (p=0.65). The results were analyzed using chi-square test, and ANOVA (p<0.05). Conclusions: Ala-inferior border of tragus line was the most parallel, and ala-superior border of tragus line was the least parallel line to the occlusal plane. The parallelism between occlusal plane and ala-superior border was more prevalent in women, while the men demonstrated significantly more parallelism with inferior border of tragus. Copyright © by authors. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.