Definition of landmarks used in this study
Z, N, J, MA, C6, and Ag were identified on the reconstructed two-dimensional posteroanterior cephalogram of a three-dimensional skull model.
Alare, ectocanine, A-point, prosthion, ectomolare, and processus zygomaticus were defined according to the study by Magnusson et al.19
*Although A-point and prosthion were one-point landmarks before expansion, they were separated into right and left landmarks after expansion.