Reliability of different three-dimensional cephalometric landmarks in cone-beam computed tomography: A systematic review

Abstract

Objectives: Conventional two-dimensional (2D) cephalometric radiography is an integral part of orthodontic patient diagnosis and treatment planning. One must be mindful of its limitations as it indeed is a 2D representation of a vaster three-dimensional (3D) object. Issues with projection errors, landmark identification, and measurement inaccuracies impose significant limitations, which may now be overcome with the advent of cone-beam computed tomography (CBCT). A systematic review of the reliability of different 3D cephalometric landmarks in CBCT imaging was conducted. Materials and Methods: Electronic database searches were administered until October 2017 using PubMed, MEDLINE via OvidSP, EBMR and EMBASE via OvidSP, Scopus, and Web of Science. Google Scholar was used as an adjunctive search tool. Results: Thirteen articles considering CBCT scans of human subjects from preexisting data sets were selected and reviewed. Most of the studies had methodological limitations and were of moderate quality. Because of their heterogeneity, key data from each could not be combined and were reported qualitatively. Overall, in 3D, midsagittal plane landmarks demonstrated greater reliability compared with bilateral landmarks. A minimum number of dental landmarks were reported, although most were recommended for use. Conclusions: Further research is required to evaluate the reliability of 3D cephalometric landmarks when evaluating 3D craniofacial complexes.

3D landmarks of Craniofacial Imaging and subsequent considerations on superimpositions in orthodontics—The Aarhus perspective

“…From the present study, it is clear that each specific landmark presents different performance in terms of reliability and accuracy along the three spatial dimensions, indicating, as previously stated for 2D analysis, that each landmark has its own “ envelope of error .” Accordingly, each landmark should be chosen and used keeping in mind its performance along the specific direction it will be used for, and for which plane it will be used. This is in agreement with what was reported in previous studies …”

“…This is in agreement with what was reported in previous studies. 18,29 As an example, according to results of this study, Gonion, which displayed poor reliability along the sagittal and vertical direction, exhibited higher reliability along the X direction, and thus can be used for assessing transverse dimensions of the dentofacial complex.…”

“…Trpkova and co‐workers made a ranking of the most reliable 2D landmarks along the sagittal and vertical directions in their systematic review . The same ranking attempt was done by some authors for 3D landmark identification, yet, it has also been advocated that a standardization of landmark selection is still needed …”

“…15 The same ranking attempt was done by some authors for 3D landmark identification, 16,17 yet, it has also been advocated that a standardization of landmark selection is still needed. 4,18 The accuracy and reliability of linear measurements on CBCTs represent other aspects that have been investigated. [19][20][21] Although these studies generally presented good results, linear measurements are not useful to determine the accuracy of landmark identification: linear measurements involve two points, thus rendering it impossible to determine the accuracy of each single landmark.…”

Automated Identification of Cephalometric Landmarks: Part 2- Might It Be Better Than human?

“…Studies on related topics in various fields have also been gaining more popularity. 3,[11][12][13][14] Although three-dimensional images have gained popularity these days, [15][16][17][18][19] two-dimensional cephalometric analysis is still a vital tool in orthodontic diagnosis and treatment planning since it provides information regarding a patient's skeletal and soft tissue. Currently, computer-assisted cephalometric analysis eliminates human-induced mechanical errors.…”