A new mandible-specific landmark reference system for three-dimensional cephalometry using cone-beam computed tomography.

Pittayapat, Pisha; Jacobs, Reinhilde; Bornstein, Michael; Odri, Guillaume A; Kwon, Min Sung; Lambrichts, Ivo; Willems, Guy; Politis, Constantinus; Olszewski, Raphaël (2016). A new mandible-specific landmark reference system for three-dimensional cephalometry using cone-beam computed tomography. European journal of orthodontics, 38(6), pp. 563-568. Oxford University Press 10.1093/ejo/cjv088

Preview

Text A new mandible-specific landmark reference system for three-dimensional cephalometry using cone-beam computed tomography.pdf - Published Version Available under License Publisher holds Copyright. Download (767kB) | Preview

OBJECTIVES

To develop a novel 3D landmark reference system that is specific for mandibular midline cephalometric landmarks and to assess its repeatability and reproducibility.

METHODS

Cone-beam computed tomography (CBCT) scans (3D Accuitomo® 170) were performed on 26 dry human skulls. The CBCT data were exported into DICOM files and imported to Maxilim® software to create 3D surface models. Two observers identified five landmarks to create a specific mid-sagittal mandibular plane: two mandibular foramina, two molar landmarks and one interincisive landmark. On this mid-sagittal mandibular plane, four mandibular cephalometric landmarks were marked: Point B, Pogonion, Gnathion and Menton. All observations were repeated by the two observers after an interval of 4 weeks. The coordinates (x, y, z) of each landmark were exported, and statistical analyses were performed to evaluate inter- and intra-rater precision.

RESULTS

The intra-observer median precision in locating all landmarks ranged between 0.17 and 0.61mm. The intra-observer repeatability was generally good with a precision under 1mm in more than 50 per cent. The overall median inter-observer precision was 0.26-2.30mm. The mandibular foramina showed the best inter-observer reproducibility. The general inter-observer reproducibility was moderate to good, except for Pogonion and Point B.

LIMITATIONS

Dry human skulls may not represent anatomical conditions found in living patients, thus the system should be validated using patients' data.

CONCLUSION

The novel reference system offered good precision and generally good to moderate repeatability and reproducibility for mandibular midline cephalometric landmark identification in three dimensions. These findings will be useful for further improvement of 3D cephalometric systems.

Interest & Impact

Downloads

126 since deposited on 23 Mar 2017
12 in the past 12 months

Citations

5 Citations in Web of Science ®
6 Citations in Scopus

Search

in Google Scholar™

Services

Actions (login required)

Edit item

Actions (login required)

Edit item