Shaikh Saquib Ahmed, K Lekha, Mathur Gaurav
Associate Professor, Department of Prosthodontics, SDM College of Dental Sciences and Hospital , Sattur, Dharwad, Karnataka, India .
Head and Professor, Department of Prosthodontics, SDM College of Dental Sciences and Hospital , Sattur, Dharwad, Karnataka, India .
J Clin Diagn Res. 2015 Feb;9(2):ZC39-42. doi: 10.7860/JCDR/2015/11820.5575. Epub 2015 Feb 1.
Correct orientation of the occlusal plane plays a vital role in achieving optimal aesthetics, occlusal balance and function of complete dentures. The use of ala tragus line for determination of occlusal plane has been a topic of debate over past many years. Also, the effect of age on level of ala tragal line has not been investigated in the past.
To determine the effect of age on location of Ala-Tragus line.
A total of 180 patients (90 males and 90 females) were selected with complete dentition and were grouped according to their age in three age groups with 60 subjects in each age group (Group A: 20-35 y, Group B: 36-50 y, Group C: 51-65 y). Right lateral profile photographs were taken with subjects having fox plane placed intraorally parallel to occlusal plane. Reference points corresponding to inferior border, middle or superior border of tragus and inferior border of ala of nose were marked on photographs. These were joined to get three different levels of Ala-Tragus line. Images were analysed photometrically and most parallel relationship was determined in between arms of fox plane (that represented the occlusal plane) and three different levels of ala tragus line. Data obtained was subjected to statistical analysis using Pearson chi-square and Likelihood-ratio chi-square test.
Significant correlation was found between age and level of Ala-Tragus line. The occlusal plane was found to be more parallel to Ala-tragus line when inferior border of tragus was considered as posterior reference point in young adult age group (20-35 y). In older age groups, occlusal plane was found to be more parallel to Ala-tragus line when middle of tragus was considered as posterior reference point.
Within the limitations of this study, it can be concluded that a definite relationship exists in between age and level of ala tragus line.
咬合平面的正确定位在实现全口义齿的最佳美学效果、咬合平衡及功能方面起着至关重要的作用。在过去许多年里，使用鼻翼耳屏线来确定咬合平面一直是一个有争议的话题。此外，过去尚未研究年龄对鼻翼耳屏线位置的影响。
确定年龄对鼻翼耳屏线位置的影响。
总共选取了180例全口牙列患者（90例男性和90例女性），并根据年龄分为三个年龄组，每组60名受试者（A组：20 - 35岁，B组：36 - 50岁，C组：51 - 65岁）。让受试者口内放置Fox平面并使其与咬合平面平行，拍摄右侧侧面照片。在照片上标记与耳屏下缘、中耳屏或上耳屏以及鼻翼下缘相对应的参考点。将这些点连接起来得到三个不同水平的鼻翼耳屏线。对图像进行光度分析，确定Fox平面（代表咬合平面）的臂与三个不同水平的鼻翼耳屏线之间的最平行关系。使用Pearson卡方检验和似然比卡方检验对获得的数据进行统计分析。
发现年龄与鼻翼耳屏线水平之间存在显著相关性。在年轻成年年龄组（20 - 35岁）中，当将耳屏下缘作为后参考点时，发现咬合平面与鼻翼耳屏线更平行。在老年年龄组中，当将耳屏中部作为后参考点时，发现咬合平面与鼻翼耳屏线更平行。
在本研究的局限性范围内，可以得出结论，年龄与鼻翼耳屏线水平之间存在明确的关系。
