Evaluation of Morphological Characteristics of the Human Ear in Young Adults

Human external ear is a morphologically complex structure and plays a vital role in the collection of sound. The present study would provide the information regarding the shape and size of the various morphological structures of the ear in normal individuals which may help the plastic surgeons to reconstruct the anatomy of the deformed ear and the physical and forensic anthropologists to study variations and establishing its use as a biometrics. The aim of the study was the morphological examination of the ear and its features to investigate the biological variations, sex differences, bilateral variations and further attempt to provide a database of external ears of a normal north Indian population.

A cross-sectional sample of 71 males and 69 females aged between 18 to 25 years were collected from Nahan city of Sirmaur District in Himachal Pradesh state of North India. Various anthroposcopic parameters were considered and evaluated through personal observation such as ear shape, form of the helix, lobule shape and its attachment to the cheeks, strength of the anti-helix, etc and were sub-divided on the basis of form, shape, elevation, etc. The SPSS statistic (IBM, Armonk, NY) software version 16 was used to evaluate the sexual dimorphism and bilateral differences.

The frequencies of various morphological characters of the human external ear were calculated using Crosstabs. The results indicate the oval and round shaped ears were reported in 37.3%; 35.92% males and 23.92%; 38.41% females, respectively. Normally rolled helix was more frequent (73.24% in males and 84.06% in females) and possessed frequently occurring Darwin's tubercle with nodosity form (88.03% in males and 90.58% in females). Hypertrichosis was mostly present on the complete helix in case of males (66.20%). Single knob tragus (40.14% in males and 52.90% in females) and double knob tragus (33.10% in males and 36.23% in females) were found to be with higher frequency in the studied population. Partially free earlobes (53.52% in males and 46.38% in females) were more common than the attached one (38.03% in males and 47.83% in females) in case of males only. The present study provides a database of morphoscopy of the external ears of North Indian population. The database may be useful in the reconstruction of the deformed ears and in the anthropological and forensic research for comparison purposes. The study may also be utilized in the prediction of ear shape and size of the studied population for facial reconstruction in forensic examinations.