A User-Friendly Protocol for Mandibular Segmentation of CBCT Images for Superimposition and Internal Structure Analysis

Abstract

Background: Since cone-beam computed tomography (CBCT) technology has been widely adopted in orthodontics, multiple attempts have been made to devise techniques for mandibular segmentation and 3D superimposition. Unfortunately, as the software utilized in these methods are not specifically designed for orthodontics, complex procedures are often necessary to analyze each case. Thus, this study aimed to establish an orthodontist-friendly protocol for segmenting the mandible from CBCT images that maintains access to the internal anatomic structures. Methods: The “sculpting tool” in the Dolphin 3D Imaging software was used for segmentation. The segmented mandible images were saved as STL files for volume matching in the 3D Slicer to validate the repeatability of the current protocol and were exported as DICOM files for internal structure analysis and voxel-based superimposition. Results: The mandibles of all tested CBCT datasets were successfully segmented. The volume matching analysis showed high consistency between two independent segmentations for each mandible. The intraclass correlation coefficient (ICC) analysis on 20 additional CBCT mandibular segmentations further demonstrated the high consistency of the current protocol. Moreover, all of the anatomical structures for superimposition identified by the American Board of Orthodontics were found in the voxel-based superimposition, demonstrating the ability to conduct precise internal structure analyses with the segmented images. Conclusion: An efficient and precise protocol to segment the mandible while retaining access to the internal structures was developed on the basis of CBCT images.

Foramen Magnum as Dimorphic Tool for Sex Determination in the Egyptian population using Cone Beam Computed Tomography: A Retrospective Study

“…5,15,16 Moreover, this study utilized CBCT data because linear measurements obtained from CBCT scans are highly accurate and reproducible. 26 This came in agreement with Akay et al, 2017 who only measured the sagittal and transverse diameters on Turkish population. Besides to, Ilgüy et al, 2014 who measured the sagittal and transverse lengths on adults of European descent and Tambawala at al., 2016 who obtained both the linear measurements and areas of FM on Indian population.…”

Lip Bumper Therapy Does Not Influence the Sagittal Mandibular Incisor Position in a Retrospective CBCT Study

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“…As the orthodontic field continues to increase its use of CBCT technology, the availability of new data continues to grow. CBCT images allow for more precise measurement of the dentoskeletal complex and visual access to measurements not previously observable on 2D radiography [ 16 , 17 ]. CBCT technology offers us the opportunity to reinvestigate previous findings without the distortion, overlap and magnification of formerly studied 2D images [ 17 , 18 ].…”

Introducing surface-to-surface matching technique to evaluate mandibular symmetry: A retrospective study

“…Technologies are encouraged to obtain information and analyze data from three dimensions, to evaluate the tooth, soft tissue, and hard tissue [ 4 , 5 , 6 ]. For example, by means of a 3-dimensional finite element model (3D FEM), the characteristics of tooth movement can be studied [ 7 ].…”