Miniscrew-assisted rapid palatal expansion (MARPE) has emerged as a noteworthy non-surgical method for treating maxillary transverse deficiency, especially in young adult patients. Studies have shown that MARPE can achieve significant dentoalveolar and skeletal expansion with long-term stability. The primary objective of this study was to assess the skeletal changes in the maxillary transverse dimension, and the secondary objective was to evaluate the dentoalveolar changes, following the use of a commercially available maxillary skeletal expander (MSE) in comparison to a custom-fabricated MARPE.

This retrospective study involved 50 young adult patients diagnosed with skeletal transverse maxillary deficiency, divided into two groups (MSE and custom MARPE), with 25 patients in each group. Pre- and post-expansion cone-beam computed tomography (CBCT) images were used to analyse skeletal, alveolar, and dental changes.

Both MSE and custom MARPE groups achieved significant skeletal and dentoalveolar expansion. However, the custom MARPE group exhibited notably greater expansion in several metrics; in the axial plane, the average expansion was 4.68±1.35mm and 3.37±1.53mm at the anterolateral maxillary walls and 3.99±1.35mm and 3.28±1.19mm at the greater palatine foramen region for custom MARPE and MSE groups, respectively (P<0.01). In coronal plane, the custom MARPE showed significantly greater transverse expansion at the mid-nasal, basal, alveolar, and dental levels.

Both MARPE systems are effective for maxillary expansion. However, the custom-fabricated MARPE may offer more favourable results, with broader and more uniform skeletal expansion. This can be especially beneficial for patients with specific anatomical requirements.