Occlusal traits in developmental dyslexia: a preliminary study

Abstract

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.