In this study the changes in soft-palate morphology and nasopharyngeal relations and nasomaxillary complex substructures after orthopaedic rapid maxillary expansion (RME) and surgically assisted RME (SARME) were compared.

A group of 10 patients received RME, a second group of 10 patients received SARME, and a third group of 10 patients served as an untreated control group. Lateral and posteroanterior cephalograms were obtained for each individual at preexpansion/precontrol (T1) and postexpansion/postcontrol (T2). In addition to descriptive parameters, the angulation, length, and thickness of the soft palate and superior and inferior pharyngeal spaces and the ratios of the length of the soft palate to the length of the superior and inferior pharyngeal spaces and maxillo-mandibular dentoalveolar structures and skeletal bases, right and left nasal cavity angles, total nasal cavity angle, nasal cavity width and nasal septum angle were also calculated. Paired t -tests were used to evaluate changes within groups following treatment/control. Analysis of variance (ANOVA) and Duncan’s tests were used to compare changes between groups, were evaluated.

No statistically significant differences were found in measurements related to soft-palate morphology or nasopharyngeal dimensions among the SARME, RME, and control groups; however, increases in soft-palate angulation and superior and inferior pharyngeal spaces after expansion/control were greater in the SARME group.

Nasal parameters significantly increased following RME and SARME. The increases in the SARME group were greater than in the other groups, but no statistically significant differences were recorded between the RME and SARME groups. Neither RME nor SARME created positional changes in nasal septum.

Conflict of interest: None declared.