Tooth formation in Sudanese children

Abstract

The aim of this study was to describe the average age of permanent mandibular tooth formation in two groups of Sudanese children using a cross-sectional design following STROBE guidelines. The Northern groups are of Arab origin whilst the Western groups are predominantly Fur of African origin (Darfur). North Sudanese sample (844 males, 802 females) consisted of equally distributed, randomly selected healthy university students and school children, whilst the West Sudanese (848 males, 401 females) consisted of a convenience sample attending religious schools in camps for the internally displaced. Panoramic radiographs (2-23 years), with known date of birth were taken. Height and weight were also measured. Developing permanent mandibular teeth were staged from radiographs (Moorrees et al., 1963). The mean age of attainments were calculated using logistic regression and comparisons carried out on 331 tooth stages to determine gender and ethnic differences. Results showed that mean age of attainment of teeth was not significantly different between the genders within each ethnic group (p>0.05) for 135 out of 155 stage comparisons. The mean age of attainment of teeth was not significantly different between same sex groups in 113 out of 174 stage comparisons (p>0.05). The canine was more advanced in females compared to males while the reverse was true for some crown and root stages of third molars. Growth indicators showed that all groups are undernourished (z-scores =< -2). Severe malnutrition had minimal effect on tooth formation of M1 and M2 (p>0.05) in Northern females. The prevalence of hypodontia (excluding third molars) was 0.7% in the Western group and 2.6% in the Northern group. The pattern of hypodontia differed between groups. In conclusion, the within group variation for most tooth stages is considerable while the differences between groups are small. The study represents the first radiographic investigation of permanent tooth formation in Africa.