Influence of Mandibular Deformity to Cranio-Facial Growth Evaluated by 3-D Cephalometry

3-D头影测量评估下颌畸形对颅面部生长的影响

• 批准号: 09671921
• 负责人: KISHI Kanji
• 金额: $ 1.98万
• 依托单位: OKAYAMA UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09671921/
• 关键词: 3-D cephalometry; mandibular deformity; cranio-facial growth; plastic model; 3-D CT; 実体計測; 立体模型; CT三次元像

3-D CT has the advantage to analyze the complex anatomical structures of the facial bones three-dimensionally compared with conventional radiograph. Observation and the measurement of 3-D image in any directions and inner structures of maxillofacial bones using cutting functions are possible on CRT.STL model (plastic actual model) reconstructed from CT images makes 3-D analysis of the facial bones easier. The aims of this study is to compare 3-D CT images and STL model in measurement accuracy and apply the measurement on STL model in the clinical cases to analyze the influence of mandibular deformity to the surrounding anatomical structure in the cranio-facial region. 3-D CT images and STL models were made in a dry skull and measurement accuracy was compared, Furthermore we applied 3-D CT and plastic models in three clinical cases (Coronoid process hyperplasia 2 cases, TMJ ankylosis 1 case) Our results showed the measurement accuracy on the plastic model was notably superior to that of … More the 3-D images on CRT.The difference in measurement accuracy might be due to the difficulty determining The measurement points in the 3-D images on CRT.3-D analysis on STL model was more easier than the ordinal 2-D analysis (cephalometry analysis) and made it possible to measure the points which is not possible on 2-D cephalometry. The specific gravity of the monomer of the pjastic material (Desolite SCR 301. Japan Gum Co. Ltd.) was 1.08 Dm and 1.15 Dp in resin. Volume shrinking was a -6.09% and -2.03% in linear shrinking by polyimerisation. ln clinical cases, plastic models made it possible to (10 close observation of the complex anatomical relationship which are easily overlooked on axial CT images and even on 3-D CT images. The plastic model duplicated the exostosis of the inner surface of the malar bone facing the concavity of the elongated process suggesting the direct functional cause of the patient's trismus. The fact that the coronoid process has been elongated in the case with TMJ ankylosis suggests that elongation could occur by the existed neighbouring bone deformity causing trismus lead to the muscle tension. It is thought that even in less extreme cases of coronoid process hyperplasia the processes can come into contact with the malar bones, thus causing trismus when the craniofacial deformity has existed. Less

与传统X线平片相比，三维CT在对复杂的面骨解剖结构进行三维分析方面具有优势。利用CRT的切割功能，可以观察和测量颌面部骨骼的任意方向和内部结构的三维图像，利用CT图像重建的STL模型（plasticactualmodel），可以方便地进行颌面部骨骼的三维分析。本研究旨在比较三维CT图像和STL模型的测量精度，并将STL模型的测量应用于临床病例，分析下颌骨畸形对颅面部周围解剖结构的影响。对3例临床病例（冠状突增生2例，颞下颌关节强直1例）进行了三维CT和三维STL模型的测量，结果表明：三维CT和三维STL模型的测量精度明显优于三维CT和STL模型的测量精度（上级）。 ...更多信息 测量精度的差异可能是由于难以确定CRT上的三维图像中的测量点。STL模型上的三维分析比常规的二维分析（头影测量分析）更容易，并且可以测量二维头影测量无法测量的点。该弹性材料（Desolite SCR 301.日本口香糖株式会社）在树脂中为1.08 Nm和1.15 Dp。体积收缩率为-6.09%，线性收缩率为-2.03%。在临床病例中，塑料模型使近距离观察复杂的解剖关系成为可能，而这些解剖关系在轴位CT图像甚至三维CT图像上容易被忽视。塑料模型复制了颧骨内表面的外生骨疣，面对延长突的边缘，这表明患者牙关紧闭的直接功能性原因。颞下颌关节强直患者冠状突延长的事实表明，可能是由于邻近骨骼变形引起张口受限，导致肌肉紧张。据认为，即使在不太极端的情况下，冠状突增生的过程中可以接触到颧骨，从而导致牙关紧闭时，颅面畸形已经存在。少

项目成果

Kanji KISHI: "Clinical Applications of 3-D CT and 3-D Plastic Model in the Maxillo-Facial Region" Oral Radiology. 13巻・2号. 21-30 (1997)

Kanji KISHI：“3-D CT 和 3-D 塑料模型在颌面部区域的临床应用”口腔放射学第 13 卷，第 2 期。21-30 (1997)