Rapid palate expansion's impact on nasal breathing: A systematic review

Proper nasal breathing is essential for the craniofacial development of children. Maxillary constriction, often associated with impaired nasal breathing, results in a narrow upper jaw, posterior crossbite, and a high palatal vault, which elevates the nasal floor and increases nasal resistance. Rapid maxillary expansion (RME) is a common orthodontic procedure that expands the maxillary dental arch, thereby widening the nasal cavity (NC). The aim of this systematic review is to evaluate the effectiveness of RME on nasal breathing in pediatric patients. We searched databases including PubMed, Web of Science, and Scopus using the keywords: 'maxillary,' 'expansion,' 'palatal,' 'RME,' 'disjunction,' and 'nasal.' The screening phase concluded with the selection of 13 publications for this review, encompassing randomized controlled trials, cohort studies, and case-control studies. The quality of the studies was assessed using established criteria, and data were extracted and analyzed. RME significantly increases the transverse dimensions of the maxilla and NC, contributing to an increase in NC volume. While structural improvements are consistent across studies, functional benefits, such as reduced nasal resistance, exhibit variability. Factors including age, pre-treatment skeletal conditions, and adenotonsillar hypertrophy influence the efficacy of RME. Certain devices, such as the Hybrid-Hyrax expander (HHE), have shown promising results in enhancing nasal ventilation. Overall, RME is an effective intervention for improving nasal breathing in children with maxillary constriction. However, further research is necessary to fully elucidate the variability in functional outcomes. Future studies should refine measurement techniques and compare different devices and protocols to optimize RME application.