Department of Paediatric Dentistry and Special Care, PaeCaMeD research, Ghent University.
Medical Imaging and Signal Processing, Infinity Lab, Ghent University, UZ Ghent.
Eur J Paediatr Dent. 2014 Sep;15(3):265-70.
Dens Invaginatus (DI) is a rare malformation of the teeth, showing a broad spectrum of morphologic variations. The aim of this study was to perform in vitro radiographic analyses of three extracted dens invaginatus (DI) teeth with complex root anatomy using plain radiographs, CBCT, MRI and micro CT techniques.
Study design: Three maxillary lateral incisors (A, B and C) from two patients were extracted due to poor prognosis and were radiographically analysed. Initially, conventional two dimensional digital radiographs were taken. Subsequently CBCT, micro CT and MRI analyses were performed.
According to the Schulze and Brand system of classification, teeth A, B and C were classified as A2, B3 and B2 respectively. To detect the relationship between the invagination to the oral cavity and pulp chamber, conventional two dimensional radiographs were of no help. CBCT and MRI images were found to be complementary to each other but provided lesser structural detail than micro CT images.
Reporting on these three DI teeth, normal conventional radiographs did not provide detailed structural information about the malformation due to geometric distortion and lack of information. Even though Oehlers classification system is the most widely used, classification by Schulze and Brand is more applicable in rare and deviant teeth.
内卷牙（DI）是一种罕见的牙齿畸形，表现出广泛的形态变异。本研究旨在通过普通 X 线片、CBCT、MRI 和 micro CT 技术对 3 颗具有复杂根解剖结构的拔除的内卷牙（DI）进行体外放射学分析。
研究设计：由于预后不佳，从两名患者中拔除了 3 颗上颌侧切牙（A、B 和 C），并对其进行了影像学分析。最初，拍摄了常规二维数字射线照片。随后进行了 CBCT、micro CT 和 MRI 分析。
根据 Schulze 和 Brand 分类系统，牙齿 A、B 和 C 分别被分类为 A2、B3 和 B2。为了检测内卷与口腔和牙髓腔之间的关系，常规二维射线照相没有帮助。CBCT 和 MRI 图像相互补充，但提供的结构细节少于 micro CT 图像。
报告这 3 颗 DI 牙，由于几何失真和信息缺失，常规射线照相不能提供关于畸形的详细结构信息。尽管 Oehlers 分类系统是最广泛使用的，但 Schulze 和 Brand 的分类在罕见和异常的牙齿中更适用。
