The Confusion of Determining the Landmark in the Craniofacial Soft Tissue Analyzes: Nasion or Sellion?

In the literature, most of the craniofacial anthropometric landmarks found on both bones and soft tissue have been clearly defined and widely used. However, it seems that few landmarks such as nasion are generally often set incorrectly. Therefore, in this study, it was aimed to examine the nasion and sellion in the dry bones and to review the definitions of each landmarks. A total of 41 adult skulls, whose nasofrontal region was not deformed and whose age, gender and ethnic origin were not known, were examined. It was found that nasion and sellion are at the same point in 24 of the 41 (58.54%) bones examined, and that in 17 of them (41.46%), sellion is below the nasion. In the bones where the sellion is below the nasion, the average distance between each two landmarks was determined as 4.53 ± 0.95 mm. Consequently, we think that it is not possible to determine nasion in the indirect craniofacial soft tissue analyzes, and it would be better to use sellion as a reference landmark instead of nasion.