The mandibular angles of dry adult human mandibles from north eastern arid zone of Nigeria.

OBJECTIVES To study and document the mandibular angle of Nigerians from the north eastern arid zone, and investigate its role as an anthropological parameter for racial and or population groups differential diagnosis, its utilization in laryngoscopy and for successful inferior alveolar nerve anesthesia. DESIGN A cross sectional study. SETTING Department of Anatomy, College of Medical Sciences, University of Maiduguri, Maiduguri, Borno State, Nigeria. SUBJECTS 60 dry adult mandibles from Nigerians who lived in Maiduguri (Borno State Capital) and its environ until their death. MAIN OUTCOME MEASURES Measurements of the right and left mandibular angles, length and height of the mandibles and the comparison of the mean angle with that of other racial and or population groups. RESULTS The mean mandibular angle (118.75 +/- 0.395 i.e. mean +/- SEM) was smaller than that of other African populations but was wider than that of the Neanderthals and similar to that of the Chinese and Peruvians. The mandible had a shorter ramus, slightly longer length resulting in a smaller angle than that of the Zimbabwean mandible. Highly significant differences occurred between the mean angle of the Nigerian mandible and those of other African population groups (p < 0.0001) except the mandibular angle of Natal Nguni and Cape Nguni populations from South Africa. There was no mutual dependence and no significant departure from linearity between the mean angle, length and height. CONCLUSION The mandibular angle in conjunction with other anthropological parameters may be useful anthropological tools in racial and or population diagnosis. The configuration of the mandible of Nigerians from the northeast arid zone may predispose them to difficult laryngoscopy and/or intubation.