Biomechanical three-dimensional finite-element analysis of maxillary prostheses with implants. Design of number and position of implants for maxillary prostheses after hemimaxillectomy

Front and isometric views of the finite-element craniofacial model after hemimaxillectomy and mesh models of maxillary prostheses. Maxillary prosthesis models with 1 and 2 zygomatic implants and superstructure mesh models.

In the maxillary prostheses models with 2 zygomatic implants in the zygomatic bone on the affected side. The alveolar bone on unaffected side with different numbers of implants: L-1 (in the maxillary lateral incisor), L-2 (in the maxillary first premolar), and L-3 (in the maxillary first molar). Type 1 was placed three implants (L-1, L-2 and L-3) in the left alveolar bone. Types 2–4 were two implants (type 2: L-2 and L-3, type 3: L-1 and L-3 and type 4: L-1 and L-2) placed, types 5–7 were one implant (type 5: L-1, type 6: L-2 and type 7: L-3) placed.

Front and lateral views of craniofacial model after hemimaxillectomy and maxillary prosthesis models. Boundary conditions and external loads are shown.

Isometric and frontal views of craniofacial and maxillary prosthesis models with distribution of von Mises stresses. Dark-blue areas represent unstressed regions, while red areas represent the most stressed regions. All plots were compared on the same chromatic scale, which is shown on the right-hand side. Maxillary prostheses models are proposed to analyze the extent of by support provided 1 and 2 zygomatic implants in the affected side. Simulated bite force was applied to distribute the vertical loads to the occlusal surface. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of the article.)

Comparison of von Mises stresses by position in the craniofacial and maxillary prosthesis model. The Z-1 group has 1 zygomatic implant (Z-1), and the Z-2 group has 2 zygomatic implants (medial, Z-M; distal, Z-D). In the left alveolar bone, the following implants were placed; L-1 (in the maxillary lateral incisor), L-2 (in the maxillary first premolar), and L-3 (in the maxillary first molar). Md is the midpoint of jugale (Ju) and zygomaxilare (Zm) (right side, R-Md; left side, L-Md).

Comparison of von Mises stresses by position in the craniofacial and maxillary prosthesis model. Using two zygomatic implants, type 1: 3 implants (L-1, L-2 and L-3) placed in the left alveolar bone. Types 2–4: 2 implants (type 2, L-2 and L-3; type 3, L-1 and L-3; type 4, L-1 and L-2), types 5–7: 1 implant (type 5, L-1; type 6, L-2; type 7, L-3).