With the objective of verifying the reproducibility and validity of three-dimensional finite element models, we fabricated finite element models and multiple models in which implants were embedded in artificial mandibles and compared implant displacements under various loading conditions; the results obtained produced the following conclusions:

The CVs as calculated from the amount of displacement under loading in the experimental, contact, and fixation models were about 5% to 10%, and all models had high reproducibility with respect to implant displacement under loading.

If three loading points were applied in the experimental and FEA models, the aspects of vertical implant displacement were similar in both.

The correlation coefficient of implant displacement under loading conditions in the experimental and contact models was 0.925, representing a high correlation, and the validity of the displacement under loading was high in the contact model.

The CV as calculated from equivalent stress values in the contact and fixation models ranged from 0.52% to 45.99%, and the reproducibility of the equivalent stress values showed considerable variance from model to model.

The above results show that the three-dimensional finite element models were reflective of displacement tendencies in the experimental model, and the results obtained had high reproducibility and validity. However, it was shown that when the validity of the absolute value of displacement was low, the reproducibility of the equivalent stress values was also inferior. Three-dimensional FEA was observed to be an effective means for investigating the behavioral tendencies of implants under loading conditions. Although there are limitations to the reproducible range, it is possible to infer phenomena to an extent if the properties are understood and the limitations are known. However, the results need to be interpreted cautiously, with a full understanding that FEA methods are purely numerical data that are mathematically enumerated.