Comparison of midsagittal reference plane in PA cephalogram and 3D CT / 대한치과교정학회지

ABSTRACT

OBJECTIVE: The aim of this study is to find the most helpful midsagittal reference plane for diagnosis in PA cephalometry compared with 3D CT. METHODS: The subjects consisted of 25 adults who showed no facial asymmetry by gross inspection. 3D CT and posteroanterior cephalogram of the subjects were taken. To find the most helpful midsagittal reference plane in PA cephalometry, we considered five kinds of midsagittal planes from which the distances to five landmarks were measured and compared the result with that of 3D CT. The midsagittal plane for 3D CT was determined by the landmarks Nasion, Sella and Basion. RESULTS: PA measurements using the midsagittal reference plane on a perpendicular plane lying through the midpoint of the right and left latero-orbitales was closest to those of 3D CT. CONCLUSIONS: It was considered that latero-orbitale perpendicular could be used as the helpful midsagittal reference plane to assess facial asymmetry in PA cephalometry.