A study on the arthroscopic temporomandibular joint disc reduction on the outcome of orthodontic patients with anterior disc displacement without reduction
Zhou Guoli, Yuan Lingjun, Liu Chao, Zhao Ning, Xia Lunguo, Fang Bing
Abstract
ObjectiveTo investigate the arthroscopic temporomandibular joint disc reduction on the outcome of orthodontic patients with anterior disc displacement without reduction.
MethodsFrom January 2012 to December 2021, forty treated orthodontic patients with anterior disc displacement without reduction (unilateral/bilateral) and no obvious articular cartilage absorption were selected from Department of Orthodontics, Shanghai Ninth People′s Hospital, Shanghai Jiao Tong University School of Medicine. The patients were (17.5±3.8) years old (12-25 years old), including 8 males and 32 females. Twenty patients who had completed arthroscopic temporomandibular joint disc reduction were included in the control group, and twenty patients with untreated temporomandibular joint disc were included in the experimental group. Model measurement (including overjet, etc.), cephalometric analysis (including ANB angle, which was formed by subspinale, nasion and supramental, etc.) and temporomandibular joint magnetic resonance imaging (including measurement of the condyle height of the displacement sides) were used to compare the difference of two groups. Objective grading system was used to evaluate the efficacy of orthodontic treatment.
ResultsThe overjet of the experimental group and the control group after orthodontic treatment was (2.19±0.76) and (1.92±0.94) mm, respectively. Both two groups achieved ideal overjet with no statistical difference (t=1.02, P=0.314). The ANB angle difference before and after treatment in the control group (-1.97°±2.87°) was greater than that in the experimental group (0.09°±1.82°), and the difference was statistically significant (t=2.72, P=0.010). The variation of condyle height before and after treatment was (0.30±1.11) mm in the experimental group and (0.82±1.25) mm in the control group, with no statistical significance (t=1.80, P=0.076). The post-treatment objective grading system scores of the experimental group and the control group were 21.00 (16.00, 24.00) and 21.00 (17.00, 25.00), respectively, which had no statistical difference (U=0.24, P=0.808).
ConclusionsIn orthodontic patients with anterior disc displacement without reduction and no obvious articular cartilage absorption, whether displaced discs are repositioned after arthroscopic surgery has no significant effect on the orthodontic treatment outcome.
Key words:
Temporomandibular joint; Orthodontics; Malocclusion; Anterior disc displacement; Overjet
Contributor Information
Zhou Guoli
Department of Orthodontics, Shanghai Ninth People′s Hospital, Shanghai Jiao Tong University School of Medicine &
College of Stomatology, Shanghai Jiao Tong University &
National Center for Stomatology &
National Clinical Research Center for Oral Diseases &
Shanghai Key Laboratory of Stomatology &
Shanghai Research Institute of Stomatology, Shanghai 200011, China
Yuan Lingjun
Department of Orthodontics, Shanghai Ninth People′s Hospital, Shanghai Jiao Tong University School of Medicine &
College of Stomatology, Shanghai Jiao Tong University &
National Center for Stomatology &
National Clinical Research Center for Oral Diseases &
Shanghai Key Laboratory of Stomatology &
Shanghai Research Institute of Stomatology, Shanghai 200011, China
Liu Chao
Department of Orthodontics, Shanghai Ninth People′s Hospital, Shanghai Jiao Tong University School of Medicine &
College of Stomatology, Shanghai Jiao Tong University &
National Center for Stomatology &
National Clinical Research Center for Oral Diseases &
Shanghai Key Laboratory of Stomatology &
Shanghai Research Institute of Stomatology, Shanghai 200011, China
Zhao Ning
Department of Orthodontics, Shanghai Ninth People′s Hospital, Shanghai Jiao Tong University School of Medicine &
College of Stomatology, Shanghai Jiao Tong University &
National Center for Stomatology &
National Clinical Research Center for Oral Diseases &
Shanghai Key Laboratory of Stomatology &
Shanghai Research Institute of Stomatology, Shanghai 200011, China
Xia Lunguo
Department of Orthodontics, Shanghai Ninth People′s Hospital, Shanghai Jiao Tong University School of Medicine &
College of Stomatology, Shanghai Jiao Tong University &
National Center for Stomatology &
National Clinical Research Center for Oral Diseases &
Shanghai Key Laboratory of Stomatology &
Shanghai Research Institute of Stomatology, Shanghai 200011, China
Fang Bing
Department of Orthodontics, Shanghai Ninth People′s Hospital, Shanghai Jiao Tong University School of Medicine &
College of Stomatology, Shanghai Jiao Tong University &
National Center for Stomatology &
National Clinical Research Center for Oral Diseases &
Shanghai Key Laboratory of Stomatology &
Shanghai Research Institute of Stomatology, Shanghai 200011, China
畸形正畸疗效的影响
畸形伴颞下颌关节不可复性盘前移位（单侧或双侧）且不伴髁突明显吸收的患者40例，患者年龄（17.5±3.8）岁（12~25岁），男性8例，女性32例。将完成关节镜下颞下颌关节盘复位术的20例患者纳入对照组，将未行颞下颌关节盘治疗的20例患者纳入未复位组。通过模型测量（包括覆盖等项目）、头影测量分析［包括ANB角（上牙槽座点、鼻根点与下牙槽座点构成的角）等项目］及颞下颌关节MRI检查（测量患侧髁突高度），比较两组各测量项目差异，通过客观评级系统评价两组正畸疗效。
畸形患者，未进行患侧关节镜下关节盘复位治疗对错
畸形正畸疗效无明显影响。
畸形有一定相关性，伴发髁突的吸收或增生以及下颌支高度降低［4, 5, 6, 7, 8, 9, 10, 11, 12］。单侧关节盘前移位患者较关节盘-髁突关系正常者下颌骨不对称更常见且更严重［6］。双侧颞下颌关节不可复性盘前移位患者下颌支缩短、下颌后缩、深覆盖等骨性Ⅱ类错
特征较关节盘-髁突关系正常及可复性关节盘前移位者更常见［7，13］。有学者认为颞下颌关节结构的稳定是高质量正畸疗效所需的下颌位置、功能、咬合和面部平衡的基础［14］。已有研究显示，未经正畸及关节治疗的颞下颌关节不可复性盘前移位青少年患者随访期间出现髁突高度降低和覆盖增大，关节盘复位后出现髁突高度增加和覆盖减小，双侧髁突高度差及颏下点偏斜减少［15, 16, 17, 18, 19］。有学者报道颞下颌关节不可复性盘前移位患者正颌-正畸联合治疗后下颌骨位置不稳定［20, 21］，也有学者认为髁突未吸收病例关节盘移位与否对下颌前移的稳定性无显著影响［22］。对于单纯正畸治疗，正畸医师需要在治疗全程注意关节问题的管理［23, 24］，但对于颞下颌关节不可复性盘前移位患者，其正畸疗效缺乏循证医学证据。关节盘未复位的病例正畸治疗后能否获得良好的前牙覆盖和咬合，下颌骨位置和侧貌如何变化，是否出现髁突吸收，关节盘复位能否获得更好的正畸疗效，是医患高度关注的问题。本项研究回顾性探讨颞下颌关节不可复性盘前移位患者关节盘复位与否对错
畸形正畸疗效的影响，以期为临床提供参考。
