Biomechanical rationale for six splinted implants in bilateral canine, premolar, and molar regions in an edentulous maxilla.

Purpose: To determine the influence of number and location of implants loaded on the stress to the bone in an edentulous maxilla using a three-dimensional finite element model (3D FEM).

Material And Methods: Computed tomographic data with the bone density of a dry skull were used to construct a 3D FEM. Titanium implants were simulated in the configuration as 14 unsplinted implants (US14), 14 splinted implants (S14), 6 splinted implants (canine, premolar, and molar regions, S6), 4 splinted implants (S4), and 6 anterior implants (incisors and canines, A6). Distributed loads of 200 N were applied on the occlusal table of the superstructures.

Results: The S6 model was subjected to a similar amount of stress and deformation to the US14 and the S14. The S4 and A6 models were subjected to approximately three times of stress under the vertical load, and approximately five times of stress under the inclined load, respectively, compared with the S6 model.

Conclusions: The 3D FEM analyses suggest that the six splinted implants configuration has a similar stress and deformation pattern as compared with naturally positioned splinted 14 implants in the edentulous maxilla.