Objectives: The aim of the study is to compare the CBCT 3D volumetric image versus 2D ray-sum simulated lateral cephalometric images derived measurements. Materials and Methods: 15 adult patients were imaged using CBCT. 2D ray-sum simulated lateral cephalometric image- right side of the patient- and 3D volumetric image were obtained and manipulated with inVivo5 dental Anatomage software. 9 angular and 6 linear measurements were measured on both 3D and 2D display modes, then reading were compared. Results: There was no statistically significant difference between the 2 display modes. Except for some measurements that showed statistically significant different that were below clinical significance. Conclusions: we can’t advice the use of one display mode over the other.