Finite Element Analysis of Bone Stress in Subperiosteal Implants
By dentalimplantsbelfast 31-12-2025 2
Subperiosteal implants were once considered a last resort in implant dentistry, largely due to limitations in design accuracy and biomechanical predictability. However, advances in digital imaging, CAD/CAM manufacturing, and material science have led to a renewed interest in these implants for patients with severe jawbone deficiency. Unlike endosseous implants, subperiosteal implants rest on the surface of the bone, making biomechanical evaluation essential for long-term success. Finite Element Analysis (FEA) has become a valuable tool for understanding how forces are transferred from implant frameworks to underlying bone. By simulating functional loads, FEA allows clinicians and engineers to assess stress patterns before treatment, supporting safer, more predictable outcomes in complex implant cases.
Understanding Subperiosteal Implants and Load Transfer
Subperiosteal implants are custom-made metal frameworks placed over the jawbone beneath the periosteum, making them suitable for patients with severe bone loss where conventional implants are not possible. Unlike endosseous implants, they distribute occlusal forces across a broader cortical bone surface, which can improve load sharing but requires precise design to avoid stress concentration.
Key biomechanical considerations include:
- Distribution of occlusal forces over cortical bone
- Framework design and anatomical adaptation
- Risk of localised bone overload with poor fit
A clear understanding of bone force interaction is essential in advanced treatments such as Dental Implant Belfast, where patient-specific anatomy strongly influences implant selection and long-term success.
Fundamentals of Finite Element Analysis in Implant Dentistry
Finite Element Analysis is a numerical method used to predict how structures respond to external forces. In implant dentistry, FEA helps evaluate stress, strain, and displacement within bone and implant components under simulated functional loading.
An FEA model typically includes:
- A three-dimensional anatomical representation
- Defined material properties for bone and implant materials
- Boundary conditions representing anatomical constraints
- Simulated occlusal or masticatory forces
The jawbone is divided into small elements, allowing detailed analysis of stress distribution. This approach has become increasingly valuable for assessing subperiosteal implants, where direct bone contact and load dispersion play a critical role in long-term stability.
Modelling Bone–Implant Interaction in Subperiosteal Implants
Accurate modelling begins with high-resolution CBCT scans, which are converted into three-dimensional digital models of the jaw. These patient-specific models allow differentiation between cortical and cancellous bone, each assigned appropriate material properties.
Key considerations during modelling include:
- Framework thickness and geometry
- Degree of bone–implant contact
- Fixation points and screw placement
- Direction and magnitude of occlusal forces
For practices providing subperiosteal dental implants Belfast, such modelling enables precise design adjustments before fabrication. Simulating functional loads helps identify areas of excessive stress that could compromise bone health or implant stability if left unaddressed.
Stress Distribution Patterns Observed in FEA Studies
FEA studies consistently demonstrate that stress concentrations in subperiosteal implants tend to occur at fixation points and along thin sections of the framework. Excessive stress in these regions may increase the risk of bone resorption or framework fatigue over time.
Common findings include:
- Higher stress in cortical bone compared to cancellous bone
- Increased stress with thinner implant frameworks
- Uneven load distribution under unilateral chewing
Balanced bilateral loading and optimal framework contouring significantly reduce peak stress values. These findings reinforce the importance of personalised implant design rather than relying on standardised frameworks.
Clinical Factors Affecting Bone Stress Outcomes
Implant Design Parameters
Implant design plays a decisive role in biomechanical behaviour. Factors influencing bone stress include:
- Framework thickness and rigidity
- Anatomical adaptation to bone contours
- Number and location of fixation screws
Thicker frameworks generally reduce stress but must be balanced against patient comfort and soft tissue adaptation.
Occlusal and Prosthetic Factors
Prosthetic design directly influences force transmission. Important considerations include:
- Occlusal scheme and bite force direction
- Prosthetic material stiffness
- Cantilever length
Shorter cantilevers and evenly distributed occlusal contacts reduce stress concentrations, improving long-term outcomes.
Clinical Implications of FEA Findings
The clinical value of Finite Element Analysis lies in its ability to inform decision making before surgery. By identifying potential stress overload, clinicians can modify implant design, fixation strategies, or prosthetic plans in advance.
Key clinical benefits include:
- Reduced risk of bone overload and resorption
- Improved implant longevity
- Enhanced patient safety
- Greater confidence in treating severely atrophic jaws
In advanced centres offering dental implant Belfast services, FEA-supported planning contributes to predictable results, particularly in patients unsuitable for traditional implant solutions.
Limitations of Finite Element Analysis in Clinical Practice
Despite its advantages, FEA has inherent limitations. Models rely on assumptions such as uniform material properties and idealised loading conditions, which may not fully replicate biological variability.
Additional limitations include:
- Inability to predict biological healing responses
- Simplification of muscle forces
- Variability in patient habits such as bruxism
Therefore, FEA should be viewed as a complementary tool rather than a replacement for clinical judgement and experience.
Material Selection and Surface Characteristics in Subperiosteal Implants
Material choice plays a crucial role in the biomechanical performance of subperiosteal implants. Titanium and its alloys are commonly used due to their strength, corrosion resistance, and biocompatibility. Surface characteristics also influence how forces are transmitted to bone and how soft tissues adapt around the framework.
Key considerations include:
- Elastic modulus and fatigue resistance
- Surface smoothness to minimise irritation
- Compatibility with surrounding bone and soft tissue
Optimised material selection supports stress control and long-term implant stability.
Future Directions: Digital Workflows and AI-Assisted Modelling
The future of subperiosteal implant planning lies in integrated digital workflows. Combining CBCT imaging, CAD/CAM design, and FEA allows seamless optimisation of implant frameworks before manufacture.
Emerging developments include:
- Real-time stress simulation during design
- Artificial intelligence–assisted optimisation
- Fully personalised biomechanical planning
These innovations promise to further improve accuracy, safety, and long-term success in complex implant cases, particularly for patients with severe bone loss.
Conclusion
Finite Element Analysis has become a powerful ally in modern implant dentistry, offering valuable insights into bone stress behaviour around subperiosteal implants. By enabling detailed biomechanical evaluation, FEA supports safer design, improved load distribution, and enhanced long-term outcomes for patients with severe jawbone deficiency.When combined with clinical expertise, digital planning, and patient-centred care, this technology transforms subperiosteal implants into a predictable solution rather than a last resort. Clinics such as Smilo Dental Implant Belfast demonstrate how evidence-based planning and advanced technology can successfully address even the most challenging implant scenarios.
