Occlusal traits in developmental dyslexia: a preliminary study.

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.