Ooi K, Inoue N, Matsushita K, Mikoya T, Minowa K, Kawashiri S, Tei K
Oral and Maxillofacial Surgery, Department of Oral Patho-biological Science, Graduate School of Dental Medicine, Hokkaido University, Kita 13 Nishi 7 kita-ku, Sapporo, Hokkaido 060-8586, Japan; Department of Oral and Maxillofacial Surgery, Graduate School of Medical Science, Kanazawa University, 13-1 Takaramachi, Kanazawa, Ishikawa, 920-8641, Japan.
Gerodontology, Department of Oral Health Science, Graduate School of Dental Medicine, Hokkaido University, Kita 13 Nishi 7 Kita-ku, Sapporo, Hokkaido 060-8586, Japan.
Br J Oral Maxillofac Surg. 2020 Nov;58(9):1084-1090. doi: 10.1016/j.bjoms.2020.05.023. Epub 2020 Jul 9.
In this study we investigated the relation between anterior disc displacement (ADD) and maxillomandibular morphology in skeletal anterior open bite with changes to the mandibular condyle. Thirty female patients (60 joints) with both conditions were evaluated. Magnetic resonance imaging of the temporomandibular joint (TMJ) was used to diagnose both ADD and changes to the mandibular condyle (erosion, osteophyte, and deformity). The relations among ADD, changes to the mandibular condyle, and maxillomandibular morphology were examined statistically. Changes to the mandibular condyle had a higher score than sym anterior open bite, the deviated side in asymmetric anterior open bite, and the non-deviated side. The score for disc displacement on the non-deviated side was lower than both the sym side and the deviated side. Unilateral changes to the mandibular condyle and unilateral disc displacement were not apparent in sym anterior open bite, but a unilateral non-displaced disc was seen only on the asymmetric side. Mandibular condylar changes were significantly more common on the deviated, than on the non-deviated, side. The SNB angle was significantly smaller, and the ANB, GZN, and SN-mandibular plane angles were significantly larger in sym anterior open bite. Overjet, ANB angle, GZN angle, and SN-MP angle were significantly larger, and the SNB angle was significantly smaller, in the presence of ADD without reduction and mandibular condylar deformity. We conclude that the prevalence of ADD without reduction and changes to the mandibular condyle were related to mandibular asymmetry and mandibular morphology in anterior open bite. This retrospective study suggests that ADD without reduction and mandibular condylar bone changes may be related to the progression of skeletal class II open bite and mandibular asymmetry in cases of skeletal open bite.
在本研究中，我们调查了伴有下颌髁突改变的骨性前牙开牙合中关节盘前移位（ADD）与上下颌形态之间的关系。对30例患有这两种情况的女性患者（60个关节）进行了评估。使用颞下颌关节（TMJ）的磁共振成像来诊断ADD和下颌髁突的改变（侵蚀、骨赘和畸形）。对ADD、下颌髁突改变和上下颌形态之间的关系进行了统计学检验。下颌髁突改变的评分高于正中前牙开牙合、不对称前牙开牙合的偏斜侧和非偏斜侧。非偏斜侧的盘移位评分低于正中侧和偏斜侧。在正中前牙开牙合中，未观察到下颌髁突的单侧改变和单侧盘移位，但仅在不对称侧可见单侧无移位盘。下颌髁突改变在偏斜侧比非偏斜侧明显更常见。正中前牙开牙合时，SNB角明显更小，而ANB、GZN和SN-下颌平面角明显更大。在存在不可复性ADD和下颌髁突畸形的情况下，覆盖、ANB角、GZN角和SN-MP角明显更大，而SNB角明显更小。我们得出结论，不可复性ADD的患病率和下颌髁突的改变与前牙开牙合中的下颌不对称和下颌形态有关。这项回顾性研究表明，不可复性ADD和下颌髁突骨改变可能与骨性开牙合病例中骨性II类开牙合和下颌不对称的进展有关。
