Assessment of the Forces Developed During Orthodontic Treatment Using the Finite Element Method

Background/Objectives: This "in silico" study investigated the biomechanical behavior of fixed orthodontic systems by analyzing the forces generated by Ni-Ti archwires and their effects on the dento-maxillary system (DMS). The objectives were to estimate force levels for 0.012″, 0.014″, and 0.016″ archwires and to evaluate the resulting stress distribution, displacement and deformation, including the influence of dental malpositions such as infraposition and linguoposition on force transmission. Methods: A three-dimensional (3D) patient-specific model of the DMS was developed and finite element analysis (FEM) was performed. Orthodontic forces were determined analytically based on archwire deformation and applied as equivalent force systems at the bracket level. The analysis was performed under simplified assumptions, including linear elastic material behavior and the absence of bracket-archwire friction. Results: The results indicated a direct relationship between archwire diameter and force magnitude. Increased diameter was associated with higher stress, displacement and deformation values. Simulated infraposition and linguoposition produced localized variations in stress distribution, highlighting the influence of tooth position on biomechanical response. Conclusions: Within the limitations of the simplified analytical and numerical model, archwire diameter plays a significant role in determining force magnitude and stress distribution in orthodontic systems. The findings provide a comparative framework for understanding force transmission, although the results should be interpreted as theoretical estimates under idealized conditions rather than direct predictors of clinical behavior.