Original Articles
Jingwen Han,Lei Wang,Shiqi Ren,Hongyu Wang,Yingyi Huang,Jiamin Li,Yan Zheng
Objective The aim of the study was to explore the correlation between temporomandibular joint (TMJ) morphological characteristics and mandibular growth potential by measuring the three-dimensional growth of the mandible before and after the growth spurt in adolescents with different TMJ morphological characteristics. Methods A transverse sample of 226 adolescents with normal growth and without orthodontic treatment was selected, and the cone beam computed tomography (CBCT) image of each patient was collected. All the samples were divided into pre-growth groups and post-growth groups based on the stages of spheno-occipital synchondrosis fusion. The condylar position, condylar height-neck ratio, condylar angle, and condylar head vertical angle were measured and calculated. According to the measurement results, all the samples were divided into groups with different TMJ morphological characteristics, and each group’s mandibular three-dimensional growth was measured and analyzed. Results Regardless where the condyle was located in the joint fossa, a significant increase in mandibular length and height was observed during the growth spurt. When the condyle was not in the median position, the growth of mandibular width was statistically significant. The growth of mandibles with short and thick condyles was significant in all directions, whereas the growth of those with long and thin condyles was statistically significant in length and height but not in width. The growth of mandibles with relatively large condyle angle was statistically significant in all three-dimensional directions, whereas those with relatively small condyle angle showed statistical significance in length and height but not in width. Mandibles with relatively large condylar head vertical angle showed significant growth in the length and height but not in width, whereas mandibles with relatively small condylar head vertical angle had statistically significant length and width growth, with no statistical significance in height. Conclusion The morphological characteristics of the TMJ can be used as a reference index to predict the growth potential of the mandible. The growth volume of mandibles with different TMJ characteristics changes in various directions.