RESUMEN
@#Facial symmetry evaluation has always been a hot topic of concern for doctors who engage in the study of facial beauty disciplines such as orthodontics, dentistry, and plastic surgery. Although scholars at home and abroad have carried out much research on the evaluation of facial symmetry with a variety of emerging technologies and methods, there is still a lack of unified standards for the evaluation of facial asymmetry due to the complexity of the content and methods and individual subjectivity. Facial asymmetry involves changes in the length, width and height of the face. It is a complex dental and maxillofacial malformation whose early identification and accurate evaluation are particularly important. Clinically, in addition to the necessary dental and maxillofacial examinations, it is also necessary to evaluate facial asymmetry with the help of corresponding auxiliary methods. This paper gives a summary of the commonly used three-dimensional evaluation methods. The evaluation methods of facial asymmetry can be divided into 5 categories: qualitative analysis, quantitative analysis, dynamic analysis, mathematical analysis, and artificial intelligence analysis. After the analysis and summarization of the characteristics, advantages and limitations of each method in clinical applications, it is found that although these methods vary in accuracy, evaluation scope, diagnosis nature and calculation method, etc., the three-dimensional evaluation methods are more objective, more accurate and more convenient and will become the mainstream evaluation method for facial asymmetry with further development of three-dimensional measurement technologies.
RESUMEN
Objective @#To study the effect of anterior traction on the temporomandibular joint in adolescent patients with skeletal Class Ⅲ malocclusion.@*Methods@#Twenty-nine patients with early permanent dentition with skeletal class Ⅲ malocclusions were measured by cephalometry and a coordinate system before and after maxillary protraction. The correlation between dentofacial structures and the temporomandibular joint was analyzed. @*Results @# After maxillary protraction, cephalometric measurements showed that the dentofacial structure changed significantly; ANB increased by 3.97° ± 2.32° (P<0.001); U1-SN increased by 4.97° ± 5.51° (P<0.001); L1-MP decreased by 1.26° ± 1.41° (P = 0.008); and MP-SN increased by 1.02° ± 3.90° (P = 0.003). The coordinate system measurement showed that the S-Fpx was decreased by 0.16 ± 1.52 mm (P = 0.041), the S-Ciy distance was significantly decreased by 0.09 ± 2.03 mm (P = 0.028), and there was no significant change in the temporomandibular joint spaces (A, P, and C) (P>0.05). Correlation analysis showed a moderate negative correlation between the posterior margin of the temporomandibular joint fossa and U1-SN (r = -0.427, P = 0.042). There was a moderate positive correlation between the leading edge of the condyle and ANB (r = 0.425, P = 0.043); there was no correlation between the joint space and dentofacial changes. @* Conclusion@#After treatment with maxillary protraction for adolescent skeletal class Ⅲ malocclusion, maxillary protraction had some effect on changes in the temporomandibular joint fossa and condyle and had no effect on the joint space.