Malocclusion and Orthodontic Treatment Need of Mentally Handicapped Children in Lagos, Nigeria

Objective: To determine the prevalence of malocclusion and orthodontic treatment need in mentally handicapped children in Lagos, Nigeria using the DAI; and to assess whether the observed malocclusion is affected by age and sex. Method: The study population consisted of 102 non-Down syndrome mentally handicapped children between 6-18years of age from 5 special schools/centres for people with special needs in Lagos. A pre-structured questionnaire was used to record the findings and socio-demographic information. The handicapped children were examined in their respective schools under natural light, using the Dental aesthetic Index (DAI) assessments. The independent student's t-test was used for the comparison of mean DAI score between any two groups. The Bonferroni correction was applied to minimize the likelihood of type one error while undertaking multiple t-tests. Results: There were no statistically significant differences (p< 0.05) in the mean DAI scores between gender and among the age groups. Severe malocclusion with treatment ` highly desirable' was found in 18%. Handicapping malocclusion where treatment was ` mandatory' was observed in 19%. One or more missing teeth were observed in 8.8%, while incisal crowding was seen in 28.4% and spacing in 58.8%. Irregularities in the maxillary and mandibular anterior segments were noted in 38.2% and 47.1%, respectively. Open bite was seen in about 25.5% of the study population. Class 1 molar relationship was found in 68.6% and 31.4% presented with half cusp and full cusp relationship. Conclusion: A large proportion of the population had very severe malocclusion where treatment is considered mandatory. The mentally disabled had higher frequencies of all the malocclusion traits than normal Nigerian children with the exception of crowding.