Comparision Between 3D and 2D Cephalometric Analysis of Orthognathis Surgery
The plan of the orthognathic surgery is commonly carried out by two-dimensional cephalometric analysis.
However, the patients with the facial asymmetry, validation of a treatment plan and the outcome has a limit by this cephalometric analysis.
Therefore we weighed three dimensions cephalometric analysis and two dimensional cephalometric analysis against the diagnosis that was in the three-dimensional form of jaw deformity with the facial asymmetry for the purpose of determining treatment validation.
Materials and methods
The object is five patients with the facial asymmetry and five patients without the asymmetry.
The three-dimensional cephalometric analysis of the X-ray computed tomography pictorial image used SimPlant O&O(R).
The two-dimensional cephalometric analysis of the roentgenographic cephalogram used Quick Ceph Studio(R).
Methods of data analysis
By the three-dimensional cephalometric analysis, we set XY , XZ, YZ planes of reference. And we set X-axis and Y-axis by the two dimensional cephalometric analysis and analyzed it.
We measured distances from these reference planes, shaft to base point to use in Ricketts analysis. Also, we measured the angle about four items ; Facial Depth, Facial Axis, Mandibular Plane Angle, Mandibular Arc. We weighed two-dimensional distance and angle against a three-dimensional analysis.
Results
The three-dimensional cephalometric analysis was a comparison before and after the operations, and the correct distance measurement in before and after of the base point and the horizontal direction was possible than two-dimensional cephalometric analysis.
Furthermore, the reference point (Go, Xi, Po, Or, Pt) was two-dimensional, and measurement of the right and left individual treatment was difficult, but the measurement of the piece according to right and left was possible in the three dimensions, and the validation of the angular difference in right and left of patients with asymmetry was possible.
Conclusions
As for the jaw deformity with the facial asymmetry, a limit was in a diagnosis by the two-dimensional cephalometric analysis, the validation, and we could evaluate the analysis point of the piece according to right and left exactly in three dimensional cephalometry, and a utility was thought to be high.
2 references
1.Gateno J,Xia JJ,Teichgraeber JF:Effect of facial asymmetry on 2-dimensional and 3-dimensional cephalometric measurements.J Oral Maxillofac Surg 69:655-662,2011
2. MORIYAMA.S,FURUTA.S,KITA.R,et al: Method of Craniomaxillofacial Superimposition by Six-Degrees-of-Freedom Search,Jpn.J.Jaw Deform.22(3):193-199,August,2012