title: Occlusion in the primary dentition. Part 1: A preliminary report on comparison of antero-posterior relationships and spacing among children of the major Nigerian ethnic groups.
abstract: This paper compares the antero-posterior occlusal pattern and arch spacing in the primary dentition of Nigerian children from the 3 major ethnic groups in the country Ibo, Yoruba and Hausa tribes. This is a cross-sectional epidemiological study involving eight randomly selected pre-primary schools and day-care centers in Ibadan and Lagos cities of Nigeria. Two hundred and sixty-nine 3-5-year-old children consisting of 125 (46.5%) males and 144 (53.6%) females were examined. A two-stage sampling method was adopted. The occlusions of the children were assessed according to the criteria by Foster and Hamilton, under natural illumination in their schools premises. Chi-square statistic was used to analyse the data. No statistically significant differences were observed in the molar and canine relationships among the ethnic groups (p > 0.05). Highly statistically significant differences were noted in relation to spacing of the arches (p = 0.001) in both the anterior and posterior segments. Also, statistically significant differences were found in relation to post canine spaces (p < 0.05) but not with pre-canine spaces. Spacing was found most in the Ibo ethnic group children. Although no statistically significant ethnic differences were found in the molar relationships of the study sample, very statistically significant differences were revealed in the spacing of the arches in both incisor and molar regions.
authors.affiliation: Orthodontic Unit, Department of Preventive Dentistry, College of Medicine/University College Hospital, University of Ibadan, Nigeria.
authors.forename: C O
authors.initials: CO
authors.lastname: Onyeaso
mesh_terms: D002675:Child, Preschool; D003430:Cross-Sectional Studies; D003481:Cuspid / Q000473:pathology; D003724:Dental Arch / Q000473:pathology; D003766:Dental Occlusion; D016021:Epidemiologic Studies; D005006:Ethnicity / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D008297:Male; D008310:Malocclusion / Q000453:epidemiology*; D008963:Molar / Q000473:pathology; D009549:Nigeria / Q000453:epidemiology; D014094:Tooth, Deciduous / Q000473:pathology*; D014504:Urban Health / Q000706:statistics & numerical data