Evaluation of Interdental Spaces of the Mandibular Posterior Area for Orthodontic Mini-Implants with Cone-Beam Computed Tomography

Abstract

Introduction: The use of mini-implants has increased in recent years because of their role in absolute anchorage, but the placement sites may affect the success or failure of the procedure, so it is very important to determine the appropriate and safe location for orthodontic mini-implants. On the other hand, the Cone Beam Computed Tomography (CBCT), which offers clear 3-Dimentional (3D) images, has been widely used in orthodontics and implant dentistry for surgical guidance of mini-implant placement. Aim: The aim of this retrospective study was to evaluate interradicular spaces between mandibular canines to second molars using cone beam 3D images. Materials and Methods: In this retrospective cross-sectional descriptive study, maxillofacial CBCT scan data were obtained from 40 adults. The 3D images were evaluated in five axial sections at 2, 4, 6, 8 and 10 mm from the cementoenamel Junction (CEJ). To determine inter-radicular spaces, tangent lines were drawn buccolingually to the roots in axial section and the minimum distance between these two lines was measured. The data was analysed using Friedman test with SPSS(ver. 13). Results: Interradicular spaces of canine to second molar increased from cervical to apical direction. The maximum distance was recorded at 4 mm from the CEJ between first and second molars. Conclusion: According to our findings there is a distinct pattern of inter-radicular space changes in mandible. Attention to this pattern during placement of mini-implants can ensure the safety of the procedure.