Horizontal Facial Thirds of Young Adults in Two South-South Nigerian Ethnic Groups

The study was undertaken to determine if there is a difference in length among the upper, middle and lower thirds of the face. Undergraduates, 18~30 years old, of Izon and Urhobo ethnic groups in two Nigerian Universities constituted the study population. Five hundred and thirty subjects, 250 Izon (127 males and 123 females) and 280 Urhobo (130 males and 150 females) participated in the study based on the systematic sampling technique. The horizontal facial thirds were measured in millimeters (mm) with the sliding caliper. Data analysis was done with SPSS 23. Descriptive and inferential statistics were used. Statistical significance was fixed at p<0.05. In all the horizontal facial thirds, the mean lengths in males were significantly higher than in females (p<0.05), except the middle third in the Izon that did not show significant difference. The mean heights of the upper and lower thirds were significantly longer in the Izon than the Urhobo, while the mean height of the middle third was significantly longer in the Urhobo than the Izon. The mean height of the lower third in males was significantly longer in the Izon than the Urhobo, while Urhobo females had significantly longer middle third than the Izon. This study suggests that the three horizontal facial segments are not equal. The outcome of this study will be useful to guide the oral maxillofacial surgeon, orthodontist and orthognathic surgeon concerned with aesthetic surgery of the face.