ABSTRACT
Background and Objective: In cephalometry, parameters like the head length, head width and cephalic index arevery important in the description of human morphology, variation in different gender and races of humanpopulation and making comparison between healthy individuals and clinical patients. Furthermore, they canalso be used to categorize human head morphology into different types and to make comparative study ofdifferent human populations. This comparative study was carried out to describe the cranial morphologyamong adolescent and young adult individuals of Bini and Igbo ethnic groups in Nigeria.Methodology: This study involved 260 Bini and 245 Igbo subjects between ages 11 – 25 years. The head lengthof each subject was measured between the glabella and inion while the head breadth measured between theparietal prominences using spreading and sliding calipers. The cephalic index of each subject was calculatedas the ratio of the head breadth to it length expressed as a percentageResults: The mean cephalic indices among the two tribes were higher in males than in females in all the agegroups studied. With increasing age, the cephalic index value decreases among the Bini tribe but increasesamong the Igbo tribe. Based on the morphological classification of the cephalic index values, the brachycephalichead type was the most prevalent among both Bini (55.4%) and Igbo (66.9) tribes while the least common headtype among the Bini and Igbo tribes were hyperbrachycephalic (8.1%) and dolicephalic (0.4%) respectively.Conclusion: The cephalic index demonstrated inter-tribal variation, prominent intra-tribal sexual dimorphismand brachycephalization is the dominant trend in cranial morphology of both Bini and Igbo tribes in Nigeria.