Abstract / Summary
Background: Mouth breathing (MB) in children is a functional alteration characterized by the substitution of nasal breathing with oral or mixed breathing. Persistent MB, particularly when occurring during sleep (nocturnal MB), may be associated with sleep fragmentation, neurobehavioral disturbances, and alterations in craniofacial development. Although established sleep-disordered breathing (SDB), particularly obstructive sleep apnea syndrome (OSAS), is well-recognized and addressed by international guidelines, children presenting with persistent or nocturnal MB without established diagnostic criteria for OSAS may remain outside conventional diagnostic pathways. The multifactorial nature of MB therefore requires the coordinated evaluation of nasal, allergic, upper airway, craniofacial, dental, and orofacial factors. Methods: This narrative review was based primarily on a structured search of the PubMed/MEDLINE database covering publications from database inception to June 2026, supplemented by manual screening of the reference lists of relevant articles and clinical guidelines. The literature was selected according to relevance to the review objectives, methodological robustness, clinical applicability, and contribution to pediatric, allergological, otorhinolaryngological, and dental/orthodontic perspectives. Priority was given to systematic reviews, meta-analyses, randomized controlled trials, clinical practice guidelines, consensus documents, and high-quality observational studies. A total of 80 references were included in the final manuscript. Results: The reviewed evidence indicates that MB may be associated with allergic and nasal conditions, upper airway obstruction, craniofacial and dental abnormalities, and orofacial functional alterations, and may coexist with SDB in selected children. The evidence was synthesized across pediatric, allergological, otorhinolaryngological, and orthodontic perspectives to develop a multidisciplinary care pathway based on the clinical identification of MB, targeted specialist assessment, objective evaluation of SDB when indicated, and individualized management and follow-up. Conclusions: MB may represent an important clinical entry point for the early recognition of potentially treatable conditions and associated SDB. The proposed multidisciplinary care pathway integrates pediatric, allergological, otorhinolaryngological, and dental/orthodontic expertise to support coordinated assessment, individualized management, and longitudinal follow-up of children with MB.