目的: 验证数字化制作简易口内哥特式弓与传统口内哥特式弓在全口义齿修复正中关系确定中的一致性。方法: 选择门诊无牙颌患者10例, 分别采用数字化制作简易口内哥特式弓(T1)与传统口内哥特式弓(T2)两种方法确定每例的正中关系; 记录两种方法临床操作时间的差异; 扫描两种上下无牙颌石膏模型的正中关系, 将Standard Triangle Language (STL)文件导入Geomagic studio软件中, 上无牙颌模型多点完全最佳拟合后, 测量T1组与T2组下颌中线区和磨牙区垂直向及唇(颊)舌向最大位置偏差; 临床试戴牙时观察T1组与T2组口内有无中线偏斜和后牙区咬合是否稳定。结果: T1、T2组临床确定正中关系时间分别为(41.90±2.64) min和(57.50±2.37) min, 配对t检验, P < 0.01, 差异有统计学意义; T1组与T2组在下颌中线区唇舌向的最大位置偏差为(0.32±0.14) mm, 垂直向的最大位置偏差为(0.40±0.23) mm; 磨牙区颊舌向的最大位置偏差为(0.35±0.23) mm, 垂直向的最大位置偏差为(0.33±0.20) mm, 在垂直向及水平向, T1组下颌相对T2组下颌的最大位置偏差均控制在0.5 mm内。在临床试戴牙过程中, T1组及T2组均未发现全口义齿中线偏离及翘动、摆动等稳定性不良现象。结论: 数字化制作简易口内哥特式弓可以用于临床全口义齿修复正中关系的确定, 不仅可以节约临床操作时间, 而且也能保证正中关系的准确性。

Objective: To verify the consistency between the digital manufacturing simple intraoral Gothic arch-tracing device and the traditional intraoral Gothic arch-tracing device in determining the centric relation of complete dentures restoration. Methods: Ten outpatients with edentulous jaws were selec-ted, and the centric relation of the patients was determined by digital manufacturing of simple intraoral Gothic arch-tracing device (T1) and traditional intraoral Gothic arch-tracing device (T2); the difference of clinical operation time between the two methods was recorded; the upper and lower edentulous jaw plaster models were scanned with two kinds of centric relation, the Standard Triangle Language (STL) files imported into Geomagic studio software to apply the best fitting of multiple points of the both upper jaw models, the fitted STL files imported into the 3 shape viewer software, and the maximum position deviations of the vertical, labial (buccal) and lingual directions of the mandibular midline area and molar areas in T1 and T2 groups measured. During the clinical complete dentures try-in, we observed whether there was midline deviation in the mouth of T1 group and T2 group, and whether the occlusion of posterior teeth was stable or not. Results: The mean time spent on determining the centric relation of T1 and T2 groups was (41.90±2.64) min, (57.50±2.37) min respectively. Paired t test was conducted in the two groups, P < 0.01 with significant statistical difference; The mean maximum position deviation between T1 group and T2 group of the midline mandibular region in labial lingual direction was (0.32±0.14) mm, that was (0.40±0.23) mm in vertical direction; the mean maximum position deviation of molar area in buccal lingual direction was (0.35±0.23) mm and that was (0.33±0.20) mm in vertical direction. In the vertical and horizontal directions, the maximum position deviation of mandibles between group T1 and group T2 was controlled within 0.5 mm. In the process of clinical complete dentures try-in, there was no deviation from the center line of dentures. There was not warping, swinging and other poor stability phenomena in T1 and T2 groups. Conclusion: The digital manufacturing of simple intraoral Gothic arch-tracing device can be used to determine the centric relation of complete dentures, which can not only save time of clinical operation, but also ensure the accuracy of the centric relation.