Title:  In vitro analysis of extracted dens invaginatus using various radiographic imaging techniques

Abstract:  Aim 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. Materials and methods 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. Results 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. Conclusion 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.