How periapical lesion size affects stress distribution in endodontically treated maxillary incisors: a finite element analysis

Periapical lesions may compromise the biomechanics of endodontically treated teeth. This study aimed to quantify, via finite element analysis (FEA), the effect of lesion size on stress distribution and deformation in a maxillary central incisor. Five 3D models (control; 2, 4, 6, 8 mm lesions) were analysed under a 300 N oblique load at 135°. Global maximum equivalent stress remained stable (89.856 MPa vs 89.673 MPa; -0.2%), whereas lesion stress increased (0.25-0.57 MPa) and deformation rose from 0.1437 to 0.1533 mm (+6.7%). Lesion enlargement minimally affects global stress but induces adverse local biomechanical changes.