Comparison of treatment effects with or without miniscrews for maxillary protraction in growing patients with Class III malocclusion

Abstract

Introduction: This study aimed to compare the skeletal and dental effects of maxillary protraction using a miniscrew-assisted rapid palatal expander (MARPE) and rapid palatal expander in growing patients with skeletal Class III malocclusion undergoing maxillary protraction.

Methods: This study included 18 patients in the facemask (FM) treatment with MARPE (group 1) and 20 patients in the FM treatment with rapid palatal expander (group 2). In addition, a control group (group 3) consisting of 21 patients undergoing no treatment affecting maxillary growth was established. Radiographic measurements were taken from lateral cephalometric radiographs at the start of FM treatment and after 3 months of treatment completion.

Results: Groups 1 and 2, receiving maxillary protraction treatment, exhibited significant increases in SNA (P <0.01) and ANB (P <0.001) values posttreatment, surpassing the control group. Group 1 showed a notably greater increase in SNA (P <0.001) and ANB (P <0.05) values than group 2. In contrast, group 2 demonstrated a significantly larger increase in FH-MP (P <0.001) and SN-U1 values (P <0.05). Both groups displayed significant advancement in the anterior border of the key ridge, the one-half point of the pterygomaxillary fissure, ANS, and point A after treatment, with group 1 showing a greater increase than group 2.

Conclusions: In treating severe maxillary hypoplasia or hyperdivergent skeletal patterns, MARPE appears to be more effective than tooth-borne expansion devices, offering greater skeletal effects with minimal dental and mandibular rotational effects.