Comparison of the immediate effects of rapid maxillary expansion with conventional anchorage versus skeletal anchorage in growing patients.

• Grant number: 24/15472-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: December 01, 2024
• End date: November 30, 2025
• Field of knowledge: Health Sciences - Dentistry - Orthodontics
• Principal Investigator: Felicia Miranda
• Grantee: Gabriel Costa da Silva
• Host Institution: Faculdade de Odontologia de Bauru (FOB). Universidade de São Paulo (USP). Bauru , SP, Brazil

Abstract

This study aims to evaluate the immediate dentoskeletal effects of rapid maxillary expansion using the Hyrax Hybrid (HH) and conventional Hyrax (CH) expanders in growing patients. Two treatment groups were analyzed. The HH group consisted of 18 individuals (8 females, 10 males; mean age 10.80 years) treated with a hybrid expander incorporating two mini-implants in the maxilla. The CH group included 14 individuals (6 females, 8 males; mean age 11.44 years) treated with a conventional Hyrax expander. All patients followed the same activation protocol: ¼ turn twice daily for 14 days, achieving 5.6 mm of expansion. Dental models were obtained at the start of treatment (T1) and immediately after the active expansion phase (T2). Occlusal radiographs of the maxilla were taken at T2. Dental models will be scanned using an intraoral scanner, and measurements of the interincisal diastema, intercanine distance, and anterior perimeter of the upper dental arch will be performed using Slicer 3D software. Occlusal radiographs will be used to measure the palatine suture opening post-expansion. Method error will be assessed with Intraclass Correlation Coefficient (ICC) and Bland-Altman analysis. Intergroup comparisons will be performed using the independent t-test, with a significance level set at 5%.