Department of Dentistry, National Taiwan University Hospital, Hsin-Chu Branch, Hsin-Chu, Taiwan.
Division of Orthodontics and Dentofacial Orthopedics, Dental Department, National Taiwan University Hospital, Taipei, Taiwan.
J Formos Med Assoc. 2024 Apr;123(4):452-460. doi: 10.1016/j.jfma.2023.10.006. Epub 2023 Oct 19.
BACKGROUND/PURPOSE: Newly developed temporary anchorage devices (TADs) serve a strong orthodontic anchorage to intrude molars for correction of anterior open bite (AOB). We measured cephalometric changes in skeletal open bite patients which developed subsequently to temporomandibular joint disorders with bilateral point contacts at terminal molars.
We retrospectively recruited 32 patients who had been treated their TMD before orthodontic correction (overbite: -3.14 ± 1.86 mm). Partial orthodontic appliances were used to intrude posterior teeth using TADs until positive OB obtained (T1). Full fixed appliances were then used to achieve proper overjet and overbite (T2). We collected lateral cephalograms before (T0), during (T1) and after (T2) treatment, and at follow-ups (T3). Using ANOVA, we analyzed the differences among these time points to determine treatment changes and stability of orthodontic results.
In this group predominantly comprising young adult women, orthodontic treatment with TADs significantly reduced upper posterior dental heights (T2-T0:-1.84 ± 0.66 mm) and facilitated the retraction and uprighting upper incisors (T2-T0: -9.92 ± 1.72°), to achieve appropriate OJ (T2-T0: -3.21 ± 0.49 mm) and OB (T2-T0: 4.10 ± 0.28 mm) with p < 0.05. Except upper posterior dental height, most of cephalometric changes including OJ, OB, and upper incisal axis remained significant at follow-ups with retention time of 3.7 ± 2.6 years. Only three out of 30 patients experienced small amount of open bite at T3.
Orthodontic correction of OJ remained relatively stable among 90 % of patients with TMJ degeneration by intrusion via TADs. This modern but conservative orthodontic approach can improve occlusal functions in skeletal open bites.
背景/目的：新开发的临时锚固装置（TAD）为磨牙内倾提供了强大的正畸支抗，用于矫正前牙开颌（AOB）。我们测量了颞下颌关节双侧磨牙接触点后发生的骨骼性开颌患者的头影测量变化。
我们回顾性招募了 32 名 TMD 患者（覆颌：-3.14±1.86mm），在正畸矫正前使用 TAD 部分矫正装置内倾后牙，直到获得正的 OB（T1）。然后使用全固定矫正器来获得适当的覆盖和覆颌（T2）。我们在治疗前（T0）、治疗中（T1）和治疗后（T2）以及随访时（T3）收集侧位头颅侧位片。使用 ANOVA 分析这些时间点之间的差异，以确定治疗变化和正畸结果的稳定性。
在以年轻成年女性为主的这组患者中，TAD 正畸治疗显著降低了上颌后牙高度（T2-T0：-1.84±0.66mm），并促进了上颌切牙的后移和直立（T2-T0：-9.92±1.72°），以获得适当的覆盖（T2-T0：-3.21±0.49mm）和 OB（T2-T0：4.10±0.28mm），p<0.05。除了上颌后牙高度外，包括覆盖、OB 和上颌切牙轴在内的大多数头影测量变化在随访时仍保持显著，保持时间为 3.7±2.6 年。在 T3 时，只有 30 名患者中的 3 名出现少量开颌。
通过 TAD 内倾矫正，90%的 TMJ 退变患者的 OJ 矫正保持相对稳定。这种现代但保守的正畸方法可以改善骨骼性开颌的咬合功能。
