The prevalence of malocclusion among a population of northern Nigeria school children.

An epidemiological survey of 1,028 children, 544 females (52.9%) and 484 males (47.1%) was carried out in Kaduna Nigeria to assess the prevalence of malocclusion in the Northern part of Nigeria. The sample population aged 11-18 years were of Northern Nigeria origin and none had received previous orthodontic treatment. From the results, normal occlusion was seen in 12.2% children, Angle's Class I malocclusion in 84.0%, 1.7% had Angle's Class II while Angle's III was observed in 2.0%. No case of Angle's Class II div 2 was seen. A reduction in the prevalence of Angle's Class II div I was seen to occur with increasing age while an increase in Angle's III malocclusion was noted in the 17-18 years age group. Spacing of the upper anterior segment was observed to occur in 45.9% of children examined while spacing of the lower anterior segment was seen in 30%. Crowding of these segments occurred in 21.6% and 36.3% respectively of the sample population. Using Jackson's method (1962) Overbite I was found to occur in 69.5% of the children examined. Deep bite (Overbite 3) occurred in only 1.6% of those examined. An overjet values of 2-4 mm was the most prevalent occurring in 70.8% of the children. A low prevalence of bimaxilliary proclination was observed (3.7%).