# Asymmetry Management During 3D-Guided Piezocorticotomy-Assisted MARPE Treatment with Direct Printed Aligners: Case Report

## TL;DR

This case report shows how 3D-guided MARPE and printed aligners can manage asymmetric dental expansion and improve facial symmetry in a patient with dentoalveolar issues.

## Contribution

The study introduces a method combining 3D-guided piezocorticotomy with MARPE and direct printed aligners to address asymmetric expansion and dentoalveolar correction.

## Key findings

- Asymmetric midpalatal expansion was observed during MARPE treatment, with greater displacement on the left side.
- Directly printed aligners enabled precise root positioning and improved occlusal symmetry after expansion.
- Significant improvements in midline orientation and transverse arch coordination were achieved over 20 months.

## Abstract

Background: Midpalatal suture expansion is effective in both growing and adult patients, and Miniscrew-Assisted Rapid Palatal Expansion (MARPE) provides greater skeletal effects and fewer dentoalveolar side effects than traditional expanders. However, asymmetric expansion remains a challenge, often influenced by pre-existing craniofacial asymmetries, appliance design, and suture morphology. In this case report, we describe asymmetric expansion with 3D-guided piezocorticotomy-assisted MARPE and its management with directly printed aligners (DPAs). Methods: A patient with facial asymmetry, a narrow maxillary arch, and multiple dentoalveolar deformities underwent pre-treatment evaluation, including root inclination analysis and CBCT imaging. A MARPE appliance with 3D-guided piezocorticotomy assistance was applied; post-expansion orthodontic treatment was digitally planned and performed with directly printed aligners. Results: During MARPE activation, asymmetric midpalatal suture disarticulation was observed, with greater displacement on the left side due to jackscrew orientation and root proximity. Post-expansion orthodontic correction with DPAs allowed precise root positioning, spatial redistribution, and improved occlusal symmetry. Over 20 months, significant improvements were achieved in midline orientation, axial root inclination, and transverse arch coordination. Conclusions: The reported case underscores the importance of pre-treatment evaluation for asymmetries and careful appliance design in MARPE protocols; in addition, it demonstrates that directly printed aligners, supported by digital planning, can provide accurate and efficient dentoalveolar correction following asymmetric expansion.