Comparison of the treatment effects of different rapid maxillary expansion devices on the maxilla and the mandible. Part 1: Evaluation of dentoalveolar changes.

INTRODUCTION

The aim of this study was to compare the dentoalveolar treatment effects of 3 rapid maxillary expansion (RME) appliances, supported by different tissues, on the maxilla and the mandible.

METHODS

Patients were assessed for eligibility, and those who met the requirements and agreed to participate were enrolled in the study. Participants were randomly allocated into 3 groups, depending on the type of expansion. The tooth-borne group (n = 16; ages, 12.63 ± 1.36 years) had RME with a tooth-borne appliance; the bone-borne group (n = 16; ages, 12.92 ± 1.07 years) had RME with a bone-borne appliance; and the hybrid group (n = 15; ages, 13.41 ± 0.88 years) had RME with hybrid appliances. Dentoalveolar effects were evaluated by digitally superimposed 3-dimensional scans of maxillary dental casts on a coordinate system and linear interdental width measurements of mandibular dental casts in the pretreatment, posttreatment, and postretention periods. For intragroup and intergroup comparisons, 1-way analysis of variance for repeated measures and multivariate analysis of variance were performed, respectively.

RESULTS

Similar dentoalveolar treatment effects were achieved in all groups with the exception of a small amount of expansion on the right side in the bone-borne group.

CONCLUSIONS

All 3 expanders led to the expansion of maxillary dentoalveolar structures with mild relapse. However, the amount of expansion of the bone-borne expander on the right side was statistically lower. Spontaneous interdental expansion was observed in the mandibular dentitions in all groups.