Objective:To explore the association between mouth breathing (MB) and functional speech sound disorders (FSSDs) in children, aiming to establish a novel theoretical basis for FSSD interventions.Methods:Eighty-nine children with an FSSD aged 4-12 years formed the FSSD group, while eighty-five age-matched healthy children served as controls. Their clinical data were processed using independent sample t-tests and chi-square tests to test for any significant differences between the two groups in terms of gender, age, mouth breathing status, post-frenotomy condition, Mandarin exposure before age 4, and delayed speech onset. Multivariate logistic regressions were evaluated to identify risk factors for FSSD in such children and to seek any association between mouth brea-thing and FSSD.Results:The regression analysis identified the following risk factors for childhood FSSD, ranked by odds ratio ( OR) magnitude: mouth breathing (adjusted OR=22.168, 95% CI=7.849-62.608, P≤0.01), delayed speech onset (adjusted OR=20.091, 95% CI=4.812-83.878, P≤0.01), age (a protective effect) (adjusted OR=0.979, 95% CI=0.962-0.997, P≤0.05). Univariate analysis of mouth breathing and associated factors revealed significant associations of FSSD with mouth breathing (χ 2=52.15, P≤0.01) and delayed speech onset (χ 2=25.873, P≤0.01). Conclusions:The significant risk factors for childhood functional speech sound disorders are mouth breathing (showing the highest adjusted OR), delayed speech onset and age. These findings suggest that early screening and therapeutic interventions for mouth breathing should be clinically prioritized to minimize FSSD risk.

Objective:To explore the association between mouth breathing (MB) and functional speech sound disorders (FSSDs) in children, aiming to establish a novel theoretical basis for FSSD interventions.Methods:Eighty-nine children with an FSSD aged 4-12 years formed the FSSD group, while eighty-five age-matched healthy children served as controls. Their clinical data were processed using independent sample t-tests and chi-square tests to test for any significant differences between the two groups in terms of gender, age, mouth breathing status, post-frenotomy condition, Mandarin exposure before age 4, and delayed speech onset. Multivariate logistic regressions were evaluated to identify risk factors for FSSD in such children and to seek any association between mouth brea-thing and FSSD.Results:The regression analysis identified the following risk factors for childhood FSSD, ranked by odds ratio ( OR) magnitude: mouth breathing (adjusted OR=22.168, 95% CI=7.849-62.608, P≤0.01), delayed speech onset (adjusted OR=20.091, 95% CI=4.812-83.878, P≤0.01), age (a protective effect) (adjusted OR=0.979, 95% CI=0.962-0.997, P≤0.05). Univariate analysis of mouth breathing and associated factors revealed significant associations of FSSD with mouth breathing (χ 2=52.15, P≤0.01) and delayed speech onset (χ 2=25.873, P≤0.01). Conclusions:The significant risk factors for childhood functional speech sound disorders are mouth breathing (showing the highest adjusted OR), delayed speech onset and age. These findings suggest that early screening and therapeutic interventions for mouth breathing should be clinically prioritized to minimize FSSD risk.