Abstract:

Objective To investigate the three-dimensional changes in hard and soft tissues before and after treatment with digitally fabricated maxillary skeletal expanders in patients with maxillary transverse deficiency. Methods Twenty late adolescents or adults with maxillary transverse deficiency treated at the Orthodontic Department of Affiliated Stomatological Hospital of Nanjing Medical University using digitally fabricated maxillary skeletal expanders were included. Cone-beam computed tomography(CBCT) scans were obtained before and after treatment. Three-dimensional measurements were analyzed using Dolphin 3D 11.95 software, and statistical analysis was performed with SPSS software. Paired t-tests were used to compare pre-treatment and post-treatment changes in hard and soft tissues. Results Significant increases were observed in anterior midpalatal suture width, posterior midpalatal suture width, maxillary apical base width, and maxillary alveolar width(P<0.001). No significant changes were found in alveolar ridge inclination, alveolar ridge height, ∠SNA(P>0.05). Significant increases occurred in apical distance, cementoenamel junction distance, and inter-fossa distance(P<0.001), while first molar inclinationand ∠U1-SN remained stable(P>0.05). Significant improvements were noted in upper airway volume, nasal floor base width, and nasal cavity width(P<0.001). Conclusion For late adolescents or adults with maxillary transverse deficiency, digitally fabricated maxillary skeletal expanders can achieve near-parallel expansion of the midpalatal suture, effectively improving maxillary transverse dimensions and airway volume while minimizing dental side effects.

Key words: maxillary skeletal expander, digital workflow, maxillary transverse deficiency