Occlusal Plane Modification in Clear Aligners Treatment: Three Dimensional Retrospective Longitudinal Study

Area of Science:

• Orthodontics
• Dental Biomechanics
• 3D Imaging in Dentistry

Background:

• Clear aligner therapy is a popular orthodontic treatment.
• Understanding its effects on skeletal and occlusal planes is crucial.
• Maxillary occlusal plane changes and their correlation with facial divergence require further investigation.

Purpose of the Study:

• To evaluate maxillary occlusal plane changes following clear aligner therapy using 3D analysis.
• To determine if these changes correlate with a patient's maxillomandibular divergence.

Main Methods:

• 3D maxillary models of 32 patients (mean age 22.3 years) treated with clear aligners were analyzed.
• The angle between the palatine and maxillary occlusal planes (Δα) was measured.
• Cephalometric measurements (NSL/MP, PP-OP, OP-MP, PP-MP, PFH/AFH%) were correlated with Δα, and patients were grouped by facial divergence.

Main Results:

• Clear aligner treatment resulted in a counterclockwise rotation of the maxillary occlusal plane (Δα).
• Δα increased in hyperdivergent patients and decreased in hypodivergent patients (p < 0.05).
• Significant positive correlation was found between Δα and NSL/MP (rho = 0.44), and negative correlation with PFH/AFH% (rho = −0.53).

Conclusions:

• Clear aligner therapy induces rotation of the maxillary occlusal plane.
• The extent of this rotation is influenced by the patient's facial divergence.
• Specific cephalometric parameters are associated with these occlusal plane changes during clear aligner treatment.