Introduction
As the right-hand dominance is undoubtedly more common in the general population, hand dominance and its association with the dominant side in double organs such as feet, eyes (vision), ear (hearing), nostrils (smell and breathing), and whether such organs have also a dominant side have long been a matter of scientific curiosity and controversy. Some authors have shown a correlation between hand dominance and feet, ear, nostrils and eyes, while some others have not (1-7).
The etiology, prevalence, treatment, and complications of nasal deviation have also long been investigated. The etiological factors can be classified into two main groups. The first and larger group includes the developmental and genetic factors. Twin studies showed similar deviations in the bony septum, also called the posterior septum, as well as in the posterior part of the cartilage septum, while anterior septal deviations did not exhibit any similarities (8). These findings have led to the conclusion that posterior septal deviations are mainly caused by genetic factors, while the anterior septal deviations may be more related to developmental factors (8, 9). The second etiological group includes the acquired causes. In most cases, an individual sustains at least one minor or major nasal trauma during his/her lifetime. The most common reasons for nasal trauma during the neonatal period include the compaction of the fetus, facial compression in the birth canal, and facedown falls during the infancy where head control is not totally complete (10), whereas being punched on the face, falls, traffic accidents, sports injuries and similar conditions play a more important role in adolescents (11).
Caudal septal deviations involve the caudal part of the septum and may lead to cosmetic problems due to low nose tip, dorsal hump, asymmetry of the nostrils, or columella deviation (12). Depending on the severity of the deviation, varying degrees of respiratory difficulties may occur due to the narrowing of the internal nasal valve (13). In some cases, the caudal septal deviations may be accompanied by other deviations of both cartilage and bony septum. It has been proposed that caudal septal deviations are more likely to be caused by traumatic and iatrogenic factors (8).
In the present study, we hypothesized those congenital nasal dorsal deviations, caudal septal deviations, and nostril asymmetry could be linked with handedness. We, therefore, aimed to investigate the incidence of nostril asymmetry and deviation of the nasal bony pyramid and caudal septum and to examine their association with the dominant hand.