Al-Khateeb Susan N, Al Maaitah Emad F, Abu Alhaija Elham S, Badran Serene A
a Associate Professor, Department of Preventive Dentistry/Orthodontics, Faculty of Dentistry, Jordan University of Science and Technology, Irbid, Jordan.
Angle Orthod. 2014 Mar;84(2):304-9. doi: 10.2319/030513-185.1. Epub 2013 Aug 5.
To assess the morphology and dimensions of mandibular symphysis (MS) in different anteroposterior jaw relationships and to investigate whether craniofacial parameters have any correlation with its shape and/or dimensions.
Lateral cephalograms of subjects with Class I, Class II, and Class III skeletal relationships were traced. Several craniofacial and MS parameters were measured. MS parameters were compared between the three groups using analysis of variance and were correlated with the craniofacial parameters using the Pearson correlation coefficient.
Larger angle of concavity of the chin, more inclination of the alveolar bone toward the mandibular plane, and larger MS dimensions and area (P < .001) were found with a Class III skeletal relationship compared to Class I and Class II relationships. The Pearson correlation coefficient between Id-Me and AFH was r = 0.83 and between Id-Me and LAFH it was r = 0.81.
The dimensions and configuration of MS in the Class III relationship were different than those in Class I and Class II relationships; the alveolar part of MS compensated for the skeletal relationship in the Class III pattern. MS dimensions were strongly correlated to anterior facial dimensions.
评估不同前后颌关系中下颌联合（MS）的形态和尺寸，并研究颅面参数与其形状和/或尺寸是否存在相关性。
对具有I类、II类和III类骨骼关系的受试者的头颅侧位片进行描记。测量了多个颅面和MS参数。使用方差分析比较三组之间的MS参数，并使用Pearson相关系数将其与颅面参数进行相关性分析。
与I类和II类关系相比，III类骨骼关系中发现下巴的凹陷角度更大，牙槽骨向下颌平面的倾斜度更大，MS尺寸和面积更大（P <.001）。Id-Me与AFH之间的Pearson相关系数为r = 0.83，Id-Me与LAFH之间的Pearson相关系数为r = 0.81。
III类关系中MS的尺寸和形态与I类和II类关系不同；III类模式中MS的牙槽部分补偿了骨骼关系。MS尺寸与面部前部尺寸密切相关。
