Condylar Movement in Relation to Hellman's Dental Age of Eruption

本研究的目的是确定颞下颌关节的髁突成分与牙齿萌出的不同阶段的关系。采用计算机辅助诊断轴向仪（CADIAX）对20例患者的helman 's Dental Age II A期、II C期、III A期和III C期的髁突通道进行分析。实验结果如下：1.实验结果表明：在每个阶段，髁突通路在所有记录的运动中都呈现凹形。在II期A，前缩时的最大平移值（sMax）为9.8 mm，侧缩时为11.5 mm，开合时为13.0 mm。与其他阶段相比，发现阶段II A的最大翻译值显著高于其他阶段。II期A的最大旋转（gamma max）值为38.1，II期C为35.0，III期A为33.2，III期C为31.1。对于水平髁倾角为5 mm的前缩运动，II期a的分析值为37.3，II期C的分析值为41.6，II期a的分析值为46.6，III期C的分析值为46.3。II期A明显低于其他阶段。II期A的髁突运动的平移幅度较小，但观察到较大的旋转幅度。在打开时髁突旋转和平移之间的关系中，在II a和II C阶段观察到初始阶段的主要旋转运动；在开始运动的最后阶段，所有阶段都观察到旋转运动的优势。在打开和关闭期间观察到髁的平移和旋转运动的差异。

The purpose of this study was to determine the pathways of the condylar-components of the temporo-mandibular joint in relation to the different stages of tooth eruption. The condylar pathways during protrusion-retrusion, lateral excursion, opening-closing of Hellman's Dental Age stage II A,II C,III A and III C were analyzed using computer-aided diagnostic axiograph (CADIAX) from a total of 20 subjects. The results were as follows :1. At each stage, the condylar pathway appeared concave at all recorded movements.2. At Stage II A,the maximum translation value (sMax) during protrusion-retrusion was 9.8 mm, lateral extrusion was 11.5 mm and opening-closing was 13.0 mm. In comparison to the other stages, the maximum translation value of Stage II A was found to be significantly higher than the other stages.3. The values of maximum rotation (gamma max) for Stage II A was 38.1ﾟ, StageII C was 35.0ﾟ, Stage III A was 33.2ﾟand Stage III C was 31.1ﾟ.4. For the protrusion-retrusion movements with a Horizontal Condylar Inclination of 5 mm, the analyzed values for Stage II A was 37.3ﾟ, Stage II C was 41.6ﾟ, Stage II A was 46.6ﾟand Stage III C was 46.3ﾟ. Stage II A was found to be significantly lower than the other stages.5. The magnitude of translation of the condylar movement of Stage II A was small, Sowever, a bigger magnitude of rotation was observed.6. In the relationship between condylar rotation and translation during opening, a predominant appearance of rotation movement in initial stage were observed for Stages II A and II C ; and translation movement for Stages III A and III C.During the final stage of opening movement, the predominance of rotation movements was observed in all stages.7. A difference in the translation and rotation movements of the condyle during opening and closing were observed.