Abstract：
BACKGROUND: Temporomandibular joint (TMJ) replacement may be indicated for various pathological conditions, and the type of condition can affect the surgical procedure and outcomes. The causes of limited range of motion after alloplastic TMJ replacement have not been extensively studied.
OBJECTIVE: The present study aimed to evaluate the impact of preoperative jaw anatomy and functional status on the immediate and long-term outcomes of total TMJ replacement using a two-component patient-specific TMJ endoprosthesis.
METHODS: This retrospective study included 31 patients who underwent total TMJ replacement surgery between 2016 and 2020. The main outcome variable was the maximal incisal opening (MIO) after treatment. Secondary outcome variables included MIO improvement and the presence and type of postoperative complications. The primary predictive variable was the preoperative initial MIO. Secondary predictive variables included sex, age, indications for TMJ replacement, preoperative occlusion, condition of the glenoid fossa and/or condyle, shortening of the mandibular ramus, sagittal mandible position, lateral chin deviation, shape of the coronoid process, and type of surgery.
RESULTS: The mean preoperative MIO was 13.0 ±8.0 mm, while the mean MIO 1 month after surgery was 20.6 ±5.5 mm, which was not statistically significant. However, at a later follow-up, functional parameters showed a significant improvement (p = 0.003), with a mean MIO of 32.5 ±5.0 mm 3 years after surgery. Statistical analysis indicated that the initial mouth opening is the strongest predictor of long-term functional recovery after TMJ replacement. Postoperative complications occurred in 4 cases (12.9%) following patient-specific endoprosthesis (PSE) placement.
CONCLUSIONS: The use of PSEs for TMJ replacement has enabled the restoration of anatomical relationships in complex clinical cases and an improvement in mouth opening. The preoperative MIO was the only factor that significantly influenced long-term functional outcomes.
OBJECTIVE: The present study aimed to evaluate the impact of preoperative jaw anatomy and functional status on the immediate and long-term outcomes of total TMJ replacement using a two-component patient-specific TMJ endoprosthesis.
METHODS: This retrospective study included 31 patients who underwent total TMJ replacement surgery between 2016 and 2020. The main outcome variable was the maximal incisal opening (MIO) after treatment. Secondary outcome variables included MIO improvement and the presence and type of postoperative complications. The primary predictive variable was the preoperative initial MIO. Secondary predictive variables included sex, age, indications for TMJ replacement, preoperative occlusion, condition of the glenoid fossa and/or condyle, shortening of the mandibular ramus, sagittal mandible position, lateral chin deviation, shape of the coronoid process, and type of surgery.
RESULTS: The mean preoperative MIO was 13.0 ±8.0 mm, while the mean MIO 1 month after surgery was 20.6 ±5.5 mm, which was not statistically significant. However, at a later follow-up, functional parameters showed a significant improvement (p = 0.003), with a mean MIO of 32.5 ±5.0 mm 3 years after surgery. Statistical analysis indicated that the initial mouth opening is the strongest predictor of long-term functional recovery after TMJ replacement. Postoperative complications occurred in 4 cases (12.9%) following patient-specific endoprosthesis (PSE) placement.
CONCLUSIONS: The use of PSEs for TMJ replacement has enabled the restoration of anatomical relationships in complex clinical cases and an improvement in mouth opening. The preoperative MIO was the only factor that significantly influenced long-term functional outcomes.
摘要：
背景：颞下颌关节（TMJ）置换可能适用于各种病理状况，和条件的类型会影响手术程序和结果。尚未广泛研究同种异体TMJ置换后运动范围有限的原因。
目的：本研究旨在评估术前颌骨解剖结构和功能状态对使用两组件患者特异性TMJ内置假体进行全TMJ置换的近期和长期结果的影响。
方法：这项回顾性研究包括2016年至2020年期间接受全TMJ置换手术的31例患者。主要结果变量是治疗后最大切口开口（MIO）。次要结果变量包括MIO改善以及术后并发症的存在和类型。主要预测变量为术前初始MIO。次要预测变量包括性别，年龄,TMJ更换的指示，术前闭塞,关节盂窝和/或髁的状况，下颌支缩短，矢状下颌骨位置,下巴外侧偏差,冠状突的形状，和手术类型。
结果：术前平均MIO为13.0±8.0mm，而术后1个月平均MIO为20.6±5.5mm，这没有统计学意义。然而,在后来的后续行动中，功能参数显着改善（p=0.003），术后3年平均MIO为32.5±5.0mm。统计分析表明，初始张口是TMJ置换后长期功能恢复的最强预测指标。患者特异性内假体（PSE）放置后4例（12.9％）发生术后并发症。
结论：在颞下颌关节置换中使用PSEs可以在复杂的临床病例中恢复解剖关系，改善张口。术前MIO是唯一显著影响长期功能结局的因素。
目的：本研究旨在评估术前颌骨解剖结构和功能状态对使用两组件患者特异性TMJ内置假体进行全TMJ置换的近期和长期结果的影响。
方法：这项回顾性研究包括2016年至2020年期间接受全TMJ置换手术的31例患者。主要结果变量是治疗后最大切口开口（MIO）。次要结果变量包括MIO改善以及术后并发症的存在和类型。主要预测变量为术前初始MIO。次要预测变量包括性别，年龄,TMJ更换的指示，术前闭塞,关节盂窝和/或髁的状况，下颌支缩短，矢状下颌骨位置,下巴外侧偏差,冠状突的形状，和手术类型。
结果：术前平均MIO为13.0±8.0mm，而术后1个月平均MIO为20.6±5.5mm，这没有统计学意义。然而,在后来的后续行动中，功能参数显着改善（p=0.003），术后3年平均MIO为32.5±5.0mm。统计分析表明，初始张口是TMJ置换后长期功能恢复的最强预测指标。患者特异性内假体（PSE）放置后4例（12.9％）发生术后并发症。
结论：在颞下颌关节置换中使用PSEs可以在复杂的临床病例中恢复解剖关系，改善张口。术前MIO是唯一显著影响长期功能结局的因素。
