Are differences in external noses between whites and Koreans caused by differences in the nasal septum?

The nasal septum plays an important role in nose development. East Asians are believed to have inherent hypoplasia of the nasal septum because East Asians have smaller noses than whites do. However, there have been no studies of nasal septum differences between whites and East Asians. We compared the nasal septum and its components in Koreans and whites using computed tomographic scan data. Twenty-seven patients of white origin and 64 patients of Korean origin older than 20 years were enrolled in this study between 2008 and 2012. We evaluated a total of 9 measurement items (5 for the nasal bones and septa as well as 4 for the external nose morphology). Sex differences in whites were the same as those in Koreans. Nasal bridge length and cartilaginous nasal bridge length were significantly longer in whites than in Koreans. However, there were no significant differences in nasal height, nasal tip projection, nasal bone length, total septal area, or most components of the nasal septum between the samples. The relative proportions of the cartilaginous septum divided by the total septal area were negatively correlated with the relative proportions of the perpendicular plate in both groups. Differences in the external nasal morphology between whites and Koreans are not caused by differences in the nasal septum.