Occlusal traits in developmental dyslexia: a preliminary study

Abstract

Letizia Perillo,1 Maria Esposito,2 Mariarosaria Contiello,1 Alessandra Lucchese,3 Annamaria Chiara Santini,2 Marco Carotenuto2 1Department of Orthodontics, Second University of Naples, Naples, 2Clinic of Child and Adolescent Neuropsychiatry, Department of Mental Health, Physical and Preventive Medicine, Second University of Naples, Naples, 3Department of Orthodontics, University of Ferrara, Ferrara, Italy Aim: The objective of the study reported here was to assess the orthodontic features in children affected by developmental dyslexia (DD). Patients and methods: A total of 28 children affected by DD (22 boys, six girls; mean age: 9.78 ± 1.69 years) were compared with 51 healthy children (38 boys, 13 girls; mean age 9.41 ± 1.48; range 7–10 years). Reading and writing skills were evaluated along with orthodontic features. Results: The DD and control groups were not significantly different in terms of total intelligence quotient (P = 0.441) and writing skills (P = 0.805 and P = 0.240, respectively), whereas significant differences were observed between the DD group and control group in both word reading (2.018 ± 1.714 vs 0.917 ± 0.563; P = 0.000) and non-word reading (2.537 ± 1.543 vs 0.862 ± 0.244; P = 0.000). Moreover, for many orthodontic features, there was no significant difference between the two groups; only in prevalence of diastemas (57.14%, P = 0.006), midline diastemas (46.42%, P = 0.007), overbite >4 mm (71.42%, P = 0.006) and overjet >4 mm (53.57%, P = 0.001), was there a statistically significant difference. According to univariate logistic regression analysis, the presence of diastemas (odds ratio [OR] 4.33; 95% confidence interval [CI] 1.61–11.65), midline diastemas (OR 4.68; 95% CI 1.61–13.43), an overbite >4 mm (OR 1.75; 95% CI 0.64–4.71), or an overjet >4 mm (OR 2.76; 95% CI 1.06–7.20) seems to play a role in the relationship between occlusal abnormalities and DD in children. Conclusion: Children with DD tend to present with altered dental features, particularly in the area of the incisors, suggesting that a persistently different tongue kinematic profile may thus affect both the developmental variability of the tongue and lip and the occlusion. Keywords: malocclusion, orthodontic features, learning disorder, kinematic profile