The Circumference Interorbital Index Of Ijaw And Igbo Ethnic Groups In Nigeria

Circumference interorbital index (C.I.I) is an important parameter in craniofacial anthropometry. The knowledge of its normal values for a particular region can be used in the treatment of certain craniofacial abnormalities. Thus the study was conducted to document and compare its values for possible ethnic differences between the two Nigerian ethnic groups (Ijaws and Igbos). A total of 1279adult Ijaws and Igbos were randomly selected for the study. These comprised 740 Ijaws and 539 Igbos. Four hundred and eight (408) of the Ijaws were males while 332 were females .Three hundred and thirty one(331) of the Igbos were males while 208 were females .The Igbos were selected from Enugu in Enugu State while Ijaws were selected from Yenagoa in Bayelsa State. The inner canthal distances (ICD) and head circumferences (HC) of the subjects were measured using standard anthropometric methods and circumference interorbital index calculated as ICD/H.C x 100. The result obtained showed that Ijaw females had a C.I.I of 8.10, Ijaw males 7.80, Igbo females 6.50, and Igbo males 6.20. Thus, Ijaw females (8.10) had the highest C.I.I while Igbo males (6.20) had the lowest. Significant differences (p<.05) were observed between the two ethnic groups. Also circumference interorbital index was found to be sexually dimorphic. The result of this study will be of importance in anthropology, genetics, forensic medicine and craniofacial surgery.