Abstract
Background: Orofacial dysfunction may co-occur with speech and language disorders. This study compared orofacial function in children with and without speech disorders using the Nordic Orofacial Test-Screening (NOT-S) and examined whether Kotlow tongue-tie severity is associated with orofacial function. Methods: This cross-sectional study included 77 children aged 5–13 years (37 with speech and language disorders [SD]; 40 without [N]). Orofacial function was screened with the NOT-S, and free tongue length was classified according to Kotlow. Nonparametric and exact tests, Poisson regression adjusted for age, sex, and systemic conditions, and sensitivity analyses were used. Results: The SD group had higher NOT-S total (median 3 vs. 1; p < 0.001; r = 0.50) and examination scores (p < 0.001; r = 0.76) than the N group, whereas interview scores did not differ. After Holm correction, facial expression, oral motor function, and speech remained more frequently impaired. The difference persisted after adjustment (incidence rate ratio 2.21, 95% CI 1.53–3.19), in children without systemic conditions, and after exclusion of the speech domain. Tongue-tie prevalence and free tongue length did not differ between groups, and no severity-related association with NOT-S scores emerged. Conclusions: Children with speech disorders had higher NOT-S scores, which persisted after adjustment for age, sex, and systemic conditions, whereas no statistically significant association between tongue-tie severity and orofacial function was demonstrated in this small sample, which does not rule out an effect. Anatomical frenulum assessment alone may be insufficient and should be complemented by functional and speech and language evaluation.