背景:TMJ形态/位置和小梁结构受各种因素的影响。切角的作用,前牙咬合关系的指标,TMJ仍不清楚。本研究旨在调查形态学,骨小梁结构,和髁的位置,以及不同切间角的II类骨骼人群的关节盂窝形态。
方法:选择150例正常面部类型和骨骼II类错牙合的成年患者,并根据其切间角度分为三组:正常,小,和大角度组。使用锥形束计算机断层扫描(CBCT)数据测量TMJ的指标,并使用海豚成像进行分析。模仿,ImageJ
结果:小角度组前后径(APD)最小,而大角度组的中外侧直径(MLD)更大。大角度组表现出显著的最大轴向面积,骨表面积,骨体积(P<0.05)。小角度组和大角度组表现出较大的骨小梁(Tb。N)和较薄的小梁厚度(Tb。Th).与正常角度组相比,小角组在轴面上表现出较大的水平髁角和较小的双侧髁角,而大角度组表现出相反的趋势。小角度组和大角度组显示冠状平面上的垂直髁角度减小,在大角度组观察到最大的减少(P<0.05)。小角度组和大角度组的关节盂窝(GFH)高度较高。大角度组表现出最大的GFH和关节盂窝宽度(GFW)(P<0.05)。
结论:大角度组有细长的椭圆形和大髁,和更深的关节盂窝,而扁平的椭圆形和较小的髁,小角度组关节盂窝较宽,较浅。小和大的切间角影响髁突小梁的结构,导致更薄的Tb。Th和更大的Th.N.在髁突位置,小角度和大角度组在轴向和冠状平面上表现出con突旋转。因此,切向角影响形态,position,和TMJ的小梁结构。这意味着我们必须注意切向角对TMJ的影响,在正畸治疗过程中,恢复正常的切角至关重要。
BACKGROUND: TMJ morphology/position and trabecular structure are influenced by various factors. The role of the interincisal angle, an indicator of the anterior occlusal relationship, on TMJ remains unclear. This study aims to investigate the morphology, trabecular bone structure, and position of the condyle, as well as the glenoid fossa\'s morphology in skeletal class II populations with different interincisal angles.
METHODS: A total of 150 adult patients with normodivergent facial types and skeletal class II malocclusions were selected and divided into three groups based on their interincisal angles: normal, small, and large angle groups. The indexes of TMJ were measured using cone-beam computed tomography (CBCT) data and analyzed using Dolphin Imaging, Mimics, and ImageJ.
RESULTS: The small angle group had the smallest anteroposterior diameter (APD), while the large angle group had a greater mediolateral diameter (MLD). The large angle group exhibited significantly the largest maximum axial area, bone surface area, and bone volume (P < 0.05). Small and large angle groups exhibited greater bone trabeculae (Tb. N) and thinner trabecular thickness (Tb. Th). Compared to the normal angle group, the small angle group exhibited a larger horizontal condylar angle and smaller bilateral condylar angles on the axial plane, while the large angle group showed the opposite trend. Small and large angle groups showed a reduced vertical condyle angle on the coronal plane, with the largest reduction observed in the large angle group (P < 0.05). Small and large angle groups had higher heights of the glenoid fossa (GFH). The large angle group exhibited the greatest GFH and width of the glenoid fossa (GFW) (P < 0.05).
CONCLUSIONS: The large angle group had elongated oval and large condyles, and deeper glenoid fossae, while a flattened-oval and smaller condyle, and wider and shallower glenoid fossae were observed in the small angle group. Small and large interincisal angle affects the structure of condylar trabeculae, resulting in thinner Tb. Th and greater Th. N. In the condylar position, small and large angle groups exhibit condylar rotation in the axial and coronal planes. Therefore, the interincisal angle affects the morphology, position, and trabecular structure of the TMJ. This implies that we must pay attention to the impact of the interincisal angle on TMJ, and it is crucial to restore the normal interincisal angle during orthodontic treatment.