3D Fea Of Clear Aligner Lower Anterior Intrusion In Periodontitis

Optimize bracketless clear aligner parameters via 3D finite element analysis of dental and periodontal biomechanics during lower anterior intrusion in periodontitis patients, providing clinical guidance. Three-dimensional modes were established: Model A (healthy), Model B (mild periodontitis), and Model C (moderate periodontitis). Each model was simulated with five aligner configurations: - Condition 1: 0.8mm single-layer hard membrane; - Condition 2: 0.2mm inner soft membrane + 0.6mm outer hard membrane; - Condition 3: 0.4mm inner soft membrane + 0.4mm outer hard membrane; - Condition 4: 0.6mm inner soft membrane + 0.2mm outer hard membrane; - Condition 5: 0.8mm single-layer soft membrane. A 0.2mm intrusion displacement was applied to analyze the displacement trends of lower anterior teeth and stress distribution in the periodontal ligaments. All 15 groups exhibited labial inclination during intrusion. Model A showed no significant PDL stress difference between single- and dual-layer membranes, with single hard membranes achieving greater intrusion. Models B/C demonstrated higher PDL stress under single-layer conditions, which decreased with. For intruding lower anterior teeth with bracketless aligners: - Model A (healthy):0.8mm single hard membrane is optimal. - Model B (mild periodontitis):0.2mm inner soft + 0.6mm outer hard membrane is recommended. - Model C (moderate periodontitis):0.6mm inner soft + 0.2mm outer hard membrane is preferred. Clinically, dual-layer aligners are advised for periodontitis patients, with thicker inner soft membranes as disease severity increases