Figure 2 CBCT scan and landmarks. Sagittal cross-section – (a) AP diameter of the incisive foramen, (b) level for ML diameter measurement of the incisive foramen, (c) mid-length of the NPC, (d) AP diameter of the nasal foramen, NCL (NPC length), (A) horizontal dimension between the cortical layer of the incisive foramen and the facial surface of the buccal bone layer, (B) horizontal dimension between the cortical layer of the nasopalatine canal to the facial surface of the buccal bone plate measured along a horizontal line starting from the palatal edge of the incisive foramen, (C) horizontal dimension between the cortical layer located at the middle point along the length of the nasopalatine canal to the facial surface of the buccal bone plate, (D) horizontal dimension between the buccal border of the nasal foramen and the cortical layer.