Three-Dimensional Force Measurements During Rapid Palatal Expansion in Sus scrofa.

Area of Science:

• Orthodontics and Dental Mechanics
• Biomedical Engineering
• Finite Element Analysis

Background:

• Rapid palatal expansion (RPE) corrects maxillary arch discrepancies but has variable outcomes due to indeterminate forces.
• Current RPE treatment relies on intuitive approaches, lacking precise 3D force and displacement measurements.
• Individualized treatment requires accurate assessment of forces and movements generated by RPE appliances.

Purpose of the Study:

• To propose and demonstrate a novel method for measuring 3D forces and displacements during RPE.
• To enable individualized and optimal orthodontic treatment through precise force quantification.
• To lay the groundwork for developing smart orthodontic appliances with real-time feedback.

Main Methods:

• Utilized a single embedded strain sensor integrated into a hyrax-design RPE appliance.
• Combined experimental strain measurements with 3D finite element analysis (FEA).
• Validated the method using a pig (Sus scrofa) maxillary jaw model.

Main Results:

• A 2.0 mm activation generated a peak force of approximately 100 N, primarily in the expansion direction.
• Over 85% of the applied activation was directly transferred to the palate and/or teeth.
• The FEA accurately estimated expansion forces and magnitudes based on strain gage data.

Conclusions:

• The developed method enables accurate 3D assessment of forces and displacements during RPE.
• This approach facilitates personalized treatment by quantifying expansion magnitudes and forces.
• The findings support the development of smart orthodontic appliances for real-time treatment monitoring.