The aim of this review was to analyze the findings reported in the literature about the effects of rapid maxillary expansion (RME) on nasal patency assessed by rhinomanometry, which measures the resistance offered by the nasal cavity to airflow, and acoustic rhinometry, which measures sectional areas and volumes of different segments of the nasal cavity. Studies using rhinomanometry have demonstrated a significant decrease of nasal resistance after RME on a significant number of patients, and also an increase in minimal nasal cross-sectional area. Studies using acoustic rhinometry have additionally shown a significant increase of anterior nasal volume. However, it is a consensus that RME is not justified only for the purpose of inducing a nasal pattern of breathing in oral breathers, despite the improvement of nasal patency caused by RME.
Palatal expansion technique; Acoustic rhinometry; Rhinomanometry
