Wong Alwyn, Woods Michael G, Stella Damien
Aust Orthod J. 2016 May;32(1):2-17.
The present study was undertaken to assess the relationship between the mandibular muscles and dentofacial skeletal morphology in children with different underlying vertical facial patterns, using three-dimensional computed tomography (3D-CT).
Thirty children (mean age 12.24 ± 1.57 years) underwent cranial CT examination for diagnostic purposes. 3D-CT images were reconstructed for the evaluation of the cross-sectional size, volume, and spatial orientation of the masseter and medial pterygoid muscles. These muscle parameters were also assessed in relation to the vertical facial pattern, gender and skeleto-dental form.
Significant differences were found in muscular angulation for subjects with different underlying patterns. Greater masseter volumes were associated with increased facial width. Greater intermolar widths were found in brachyfacial subjects, with less acute muscular angulations in relation to horizontal reference lines, compared with dolichofacial subjects. This was also more obvious in the maxillary arch.
Clinicians should note the likely differences in masseter and medial pterygoid orientation and volume in subjects with different underlying vertical facial patterns and that these differences may, in turn, be related to both facial skeletal width and naturally-occurring transverse dental arch dimensions.
本研究旨在利用三维计算机断层扫描(3D-CT)评估不同垂直面型儿童下颌肌肉与牙颌面骨骼形态之间的关系。
30名儿童(平均年龄12.24±1.57岁)因诊断目的接受了头颅CT检查。重建3D-CT图像以评估咬肌和翼内肌的横截面尺寸、体积和空间方向。还根据垂直面型、性别和骨骼牙型对这些肌肉参数进行了评估。
不同基础面型的受试者在肌肉角度上存在显著差异。咬肌体积增大与面部宽度增加有关。短面型受试者的磨牙间宽度更大,与长面型受试者相比,其相对于水平参考线的肌肉角度不那么锐利。这在上颌弓中也更为明显。
临床医生应注意不同垂直面型受试者咬肌和翼内肌方向及体积可能存在的差异,而这些差异反过来可能与面部骨骼宽度和自然出现的牙弓横向尺寸有关。