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Comparison of the palatal expansion obtained via the use of the rapid maxillary expander compared with surgically assisted rapid maxillary expansion.

BACKGROUND
The aim of this retrospective study was to evaluate and compare cephalometrically the skeletal and dental effects of maxillary expansion by the rapid maxillary expander compared to a surgical assisted rapid maxillary expansion.


METHODS
The records which included 102 patients (50 female, 52 male) with maxillary bilateral cross bite caused by narrowness of the apical base are collected and divided into two treatment groups: the first group (63 patients, 36 male and 27 female) included patients who had been treated with an orthopedic rapid maxillary expander. The second group (39 patients, 16 male, 23 female) included patients who had been treated by a surgical assisted rapid maxillary expansion. For each patient two frontal cephalograms, one taken before treatment (T0) and a second one after the retention phase (T1), were analyzed. Descriptive statistics included the means and standard deviations (SD). The mean differences in cephalometric measurements at T0 and T1 were examined. Statistical analysis was undertaken using a T test for paired samples. Statistical significance was considered at P<0.05 level.


RESULTS
Both the therapeutic approaches have shown a statistically significant widening of the maxilla and a symmetrization of the two halves of the bone, at both skeletal and dental levels.


CONCLUSIONS
Rapid maxillary expander and surgically assisted rapid maxillary expansion SARME can be used for the resolution of malocclusions characterized by a transverse maxillary hypoplasia. The choice between RME and SARME is linked to the age of the patient, and the biological stage of the maxillary suture.