Finite Element Analysis (FEA) of a Premaxillary Device: A New Type of Subperiosteal Implant to Treat Severe Atrophy of the Maxilla

Finite Element Analysis (FEA) of a Premaxillary Device: A New Type of Subperiosteal Implant to Treat Severe Atrophy of the Maxilla

1. Scientific Reference

• Study Title: Finite Element Analysis (FEA) of a Premaxillary Device: A New Type of Subperiosteal Implant to Treat Severe Atrophy of the Maxilla
• Authors: Alessandro Cipollina, Mario Ceddia, Natalia Di Pietro, Francesco Inchingolo, Margherita Tumedei, Tea Romasco, Adriano Piattelli, Alessandro Specchiulli, Bartolomeo Trentadue
• Scientific Journal: Biomimetics
• Year of Publication: 2023
• DOI: 10.3390/biomimetics8040336

2. Scientific Background

The management of severe maxillary atrophy remains one of the most complex challenges in oral implantology. When the available bone volume becomes insufficient, conventional treatment protocols often require advanced bone reconstruction procedures or the use of specialized implants designed to utilize anatomical areas distant from the edentulous site.

Although approaches such as bone grafting, sinus augmentation, zygomatic implants, or pterygoid implants have demonstrated clinical value, they may be associated with considerable surgical complexity and a risk of complications. In this context, the emergence of customized subperiosteal devices developed through digital technologies represents a particularly active area of research.

The analyzed study is part of this trend and evaluates a new premaxillary device intended for implant rehabilitation of severely atrophic maxillae through a finite element biomechanical analysis.

3. Study Objective

The primary objective of the authors was to evaluate the biomechanical behavior of a new premaxillary subperiosteal device (Premaxillary Device – PD) intended for the rehabilitation of severely atrophic maxillae.

The study aimed to determine the distribution of mechanical stresses generated within the device, the implants, the prosthetic abutments, and the basal bone in order to assess the biomechanical feasibility of this therapeutic approach.

4. Methodology

This research corresponds to a preclinical numerical study using Finite Element Analysis (FEA).

The authors developed a three-dimensional model of the premaxillary device using computer-aided design software. A virtual model of a completely edentulous maxilla presenting severe bone atrophy was then created from computed tomography images.

The device was modeled using Ti6Al4V titanium alloy and positioned on basal bone exhibiting the mechanical properties described in the literature. Simulations were performed using ANSYS software.

Two loading conditions were evaluated:

• axial load of 200 N;
• oblique load of 200 N applied at 45°.

Stresses were analyzed according to the Von Mises criterion.

No patients or clinical implants were included, as the study relied exclusively on numerical simulation.

5. Main Results

The simulations demonstrated a relatively homogeneous distribution of stresses throughout the entire premaxillary device.

Under a 200 N axial load, the stresses observed on the device remained moderate, generally ranging between 5 and 15 MPa. The most highly stressed areas mainly corresponded to the prosthetic abutments and threaded connections. The most critical region reached approximately 34.4 MPa.

When the load was applied obliquely at 45°, stresses increased throughout the entire system. The basal bone exhibited stresses ranging from 3 to 15 MPa, while stresses observed within the device reached values between 40 and 250 MPa.

The abutments represented the most highly stressed components, with values reaching approximately 270 MPa. Despite this increase under oblique loading, the stresses remained below the mechanical limits reported for the titanium alloy used.

The authors concluded that the device allows a favorable distribution of loads without generating excessive stress concentrations likely to compromise the biomechanical stability of the system.

6. Clinical Analysis

This study primarily provides biomechanical information regarding a rehabilitation solution intended for patients presenting with advanced maxillary atrophy.

The interest of the evaluated device lies in its objective of bypassing certain complex reconstructive procedures that are usually required in cases of severe bone deficiency. The results suggest that the architecture of the device promotes a relatively homogeneous distribution of stresses to the basal bone, which is an essential factor in limiting mechanical overload phenomena that may lead to bone resorption or implant failure.

The analysis also highlights the importance of oblique loading, whose impact is significantly greater than that of axial loading. This observation is consistent with biomechanical principles already established in implantology, according to which the lateral components of occlusal forces often represent the most critical stresses.

However, these results should be interpreted with caution. An FEA study does not faithfully reproduce the biological complexity of the oral environment. Bone remodeling phenomena, individual variations in bone quality, implant micromovements, and actual masticatory conditions cannot be fully simulated. Therefore, the obtained results should be considered exploratory data supporting the mechanical feasibility of the concept rather than clinical proof of its effectiveness.

7. Clinical Applications

The results of this study may be of interest in several clinical situations:

• implant rehabilitation of severely atrophic maxillae;
• management of edentulous patients with limited bone volume;
• situations in which bone grafting or sinus augmentation procedures are considered complex or high-risk;
• development of customized subperiosteal devices produced using CAD/CAM technologies;
• digital planning of complex implant rehabilitations.

The study essentially provides information regarding the potential biomechanical stability of the concept rather than its long-term clinical performance.

8. Level of Evidence, Limitations and Transparency

The level of evidence of this publication is relatively limited, as it is a preclinical numerical study based on finite element analysis.

The main limitations are directly acknowledged by the authors. The materials were considered homogeneous, isotropic, and linearly elastic. Complete osseointegration was also assumed during the simulations. These assumptions inevitably simplify real biological conditions.

No clinical results in humans are presented in this study, and no direct clinical comparison with other therapeutic techniques was performed.

The authors declare no conflicts of interest.

Therefore, cautious interpretation is required before any clinical extrapolation.

9. Key Study Points

• Study Type: Preclinical finite element analysis (FEA) study
• Level of Evidence: Low to moderate (experimental numerical study)
• Population or Number of Studies Analyzed: Not applicable
• Number of Patients or Implants: No patients included
• Follow-up Duration: Not applicable
• Primary Outcome Evaluated: Distribution of biomechanical stresses
• Main Result: Favorable stress distribution across the basal bone and the premaxillary device
• Scientific Conclusion: The premaxillary device demonstrated biomechanical behavior compatible with its potential use in severely atrophic maxillae
• Potential Limitations: Numerical modeling, simplifying assumptions, and absence of clinical validation

10. Scientific Impact

This publication contributes to the development of modern subperiosteal devices intended for the rehabilitation of patients with advanced maxillary atrophy.

Its main contribution lies in the detailed biomechanical evaluation of a relatively recent therapeutic concept. The results support the hypothesis that a customized premaxillary device could provide load transmission compatible with the mechanical capacities of both the basal bone and the implant material used.

The study also illustrates the growing importance of digital simulation tools in the design of new implant solutions. By identifying areas of stress concentration before any clinical application, these methods may contribute to the optimization of implant designs.

However, this contribution remains essentially theoretical. Prospective clinical studies with medium- and long-term follow-up will be necessary to confirm the clinical relevance and durability of the concept.

11. Editorial Conclusion

This study provides an in-depth biomechanical evaluation of a new subperiosteal device intended for the rehabilitation of severely atrophic maxillae. Numerical simulations suggest a favorable stress distribution and mechanical resistance compatible with the investigated loading conditions.

Although these results are encouraging for research in digital implantology and maxillary reconstruction, their significance remains limited by the absence of clinical validation. Consequently, this publication represents an interesting preliminary step in the development of new alternatives to more invasive reconstructive protocols.