Prevalence of malocclusion in individuals with and without intellectual disability: A comparative study

The aim of this study was to compare the prevalence malocclusion between individuals with intellectual disability (ID) and a control group without disability (NID).

A total of 202 individuals (123 with ID and 79 with no impairment) were included in the study. Data were collected through oral examinations using the Angle classification of malocclusion and the dental aesthetic index (DAI).

According to Angle's classification of malocclusion, it was found that 37.6% of all participants presented malocclusion. Class II malocclusion was the most common form of malocclusion in both groups, whereas class III cases were present almost exclusively in ID group (91.7%). The mean DAI score was 30.85 (± 13.7), being higher in the ID group (32.80) than in the control group (27.81; p = 0.003). A total of 45 (22.3%) participants had DAI scores of 36 and above, which indicate a handicapping malocclusion requiring mandatory orthodontic treatment. From those needing mandatory orthodontic treatment, the majority (84.4%) belonged to ID group. Mandibular irregularity (56.4%) and incisal segment crowding (45%) were the most common features of the malocclusion. Linear regression indicates that having an intellectual disability predicts severe or very severe malocclusion.

In this study, the prevalence of malocclusion was found to be higher and more severe in intellectual disabled participants. The dental practitioner should understand the particular relevance of this problem especially in patients with intellectual disabilities where impaired oral functions and poor appearance may further complicate oral health and increase negative social responses.