Objective: The aim of this study was to evaluate through nasal fiber optic endoscopy and rhinomanometry the patency of upper nasal airways in patients treated with rapid palatal expansion Study design: 30 patients (12 males and 18 females) aged 7-11 years with transverse maxillary constriction underwent rhinomanometric and fiberoptic examination before (T0) and after rapid palatal expansion (T1).The amount of nasopharynx obstruction was quantified with reference to the full choanal surface. Nasal resistance was recorded separately for right and left sides, and combined for both sides. The differences in nasopharynx obstruction and in nasal resistance between T0 and T1 were statistically evaluated.
Results: The amount of nasopharynx obstruction significantly decreased after palatal expansion (p<0.001). Total nasal inspiration and expiration resistance significantly decreased at T1 (p<0.001). The reduction ranged between 0. 23 and 0. 66 Pa/cm3/s for inspiration and between 0. 20 and 0,.58 Pa/cm3/s for expiration. A statistically significant positive correlation existed between the T1-T0 differences in the amount of nasopharynx obstruction and the T1-T0 differences in expiration nasal airway resistance (Spearman's correlation coefficient rho = 0.38; p = 0.03).
Conclusions: Rapid maxillary expansion has an influence on nasal resistance and improves the patency of upper airways in patients with minor or moderate breathing problems.
Keywords: fiberoptic endoscopy; maxillary contraction; nasal obstruction; rapid palatal expansion; rhinomanometry.