Malocclusion and orthodontic treatment need of secondary school students in Nigeria according to the dental aesthetic index (DAI)

The aims of this study were to measure the distribution, prevalence and the severity of malocclusion and treatment need amongst randomly selected (n=703) rural and urban Nigerian children aged 12-18 years (mean 14.0+/-1.84) using the dental aesthetic index (DAI), and to assess whether malocclusion was affected by age, gender and socio-economic background. Data were collected according to the method recommended by WHO. Most of the children (77.4 per cent) had a dental appearance which required no orthodontic treatment. Over 13 per cent fell into the group where treatment for malocclusion is considered to be 'elective'. However, a substantial proportion (9.2 per cent) of the population had severe to handicapping malocclusion where treatment is 'highly desirable' or 'mandatory'. There were no statistically significant differences (P>0.05) in DAI scores between age groups, gender and socio-economic background. This study also found that Nigerian adolescents had better dental appearance and less orthodontic treatment need compared with the Caucasian and Oriental populations.