From Strength
to System Behaviour.
Energy-based evaluation of clinically relevant interface stability across implant, cement and biomaterial interfaces. We measure what happens after the peak, that is where it is decided whether a system holds or fails abruptly.
01 · The Difference
Same peak force.
Completely different behaviour.
Two bonds reach the same Fmax. One fails abruptly at the peak, the other keeps redistributing load and fails in a controlled manner. This information is not provided by any classical pull-off or peel test. It is the basis for whether a bond really holds under realistic loads.
What happens after the peak
The peak is just one point. What matters is the energy an interface still carries after the peak, the difference between controlled and abrupt failure.
- Brittle. The peak is reached, then the force drops abruptly. Low dissipated energy, small damage tolerance. Under realistic loads: abrupt system failure.
- Ductile. Same peak, but the force is held afterwards. The interface distributes load across a wider displacement range. High dissipated energy, robust system behaviour.
- Identical Fmax ≠ identical system behaviour
Classical pull-off and peel tests only see the peak, and miss the actual difference.
What matters is what happens after the peak. We capture it in energy terms via the specific dissipated energy GF, derived from the full load-displacement curve. This produces a sound picture of the real failure behaviour of a system.
02 · Methodology
How we measure
Methodology in three loading modes, Mode I (opening), Mode III (tearing) and Mixed Mode I/II (combined loading). Energy-based evaluation via specific dissipated energy (GF) captures the full failure behaviour, well beyond peak values alone.
Mode I — Opening
Normal load perpendicular to the interface. Characterises tensile and peel failure, for example at cement-bone interfaces.
Mode I/II — Mixed
Superposition of opening and in-plane shear. Real combined loading, where interfaces tend to fail earlier.
Mode III — Shear
Out-of-plane shear. Models torsional load as it occurs at modular junctions and screw interfaces.
Analysis focus
Interface-controlled crack initiation
When and at what load the crack initiates at the interface itself, not in the surrounding bulk material.
Stable and unstable crack propagation
Whether the crack propagates in a controlled, gradual manner or fails abruptly and brittle.
Energy dissipation
How much energy the interface absorbs and dissipates before complete separation.
DISCLAIMER · This methodology serves exclusively engineering, material and interface analysis. It does not replace medical advice, clinical evaluation or regulatory approval.
03 · Implant Interfaces
Where interface behaviour matters
Bone cement systems, adhesive bonds, the bone-implant bond, modular junctions, fixation systems and additively manufactured biomaterials, everywhere where it is not the material alone but the interface that drives system behaviour and clinically relevant interface stability.
04 · Stability Matrix
From interface data
to system decisions.
Stability-driven evaluation: quantify interface behaviour, predict system performance, drive smarter decisions. Similar strength does not mean similar behaviour: the interface determines long-term reliability.
Similar strength means fundamentally different behaviour. Interfaces can determine long-term system reliability.
Each bubble can represent any clinically or technically relevant parameter, such as:
- Viscosity
- Antibiotic loading
- Porosity
- Mixing protocol
- Ageing condition
- Interface roughness
- And many more
Choose the variable that matters most for your system.
05 · Readiness
Methods, specimens and fixtures. All ready.
The testing logic is established. Specimen design, fixtures and the evaluation chain are in place. Projects can start immediately once interface pairings and cement systems are defined.
What is in place
- 01 Validated Mode I, Mixed Mode I/II and Mode III specimen geometries and in-house test fixtures in a documented, validated design.
- 02 Reproducible specimen preparation for cement, adhesive and bone-implant interfaces, proven across all specimen types.
- 03 Standardised metallic substrates, titanium and cobalt-chrome alloys, with defined surface conditions, plus an evaluation chain via dissipated energy GF including statistical scatter evaluation.
- 04 Defined project workflow: you send your specimens, we test and deliver the result report classifying your cement system, typically within a few weeks.
As a quality assurance stage
When a new, more cost-effective cement system is under consideration, the energy-based analysis verifies in advance whether its failure behaviour is comparable to the established system. The switch becomes a documented decision rather than an assumption.
SampleKits
Standardised SampleKits let partners prepare their specimens to a defined specification themselves. This makes recurring comparison series faster to set up.
NOTE · BioInterfaces is not an accredited test laboratory. The methods, metrics and results presented serve engineering and interface analysis purposes under controlled laboratory conditions. Projects can start as soon as interface pairings and cement or adhesive systems are defined.
06 · For Whom We Work
Three audiences. Three levels of depth.
From exploratory baseline characterisation to product-near validation. We connect where the question belongs.
Universities & Research Groups
Orthopaedic and dental chairs, research groups with their own material development.
- Energy-based characterisation of new material classes
- Publication-grade evaluation and data quality
- Mode-I/II/III design for individual specimens
Cement & Adhesive Manufacturers
Manufacturers of bone cements, dental adhesives and biomedical glues.
- Comparison of formulations beyond the strength peak
- Energy-based differentiation in the competitive field
- Robust energy metrics as a data basis for product development
Implant Manufacturers
Manufacturers of endoprosthetics, trauma implants, dental implant systems.
- System evaluation implant + fixation + bone
- Lifetime-relevant energy metrics
- Risk differentiation at modular junctions
07 · About
About us
BioInterfaces is a specialised brand of Fracture Analytics®, focused on clinically relevant interface stability and the system behaviour of medical-technical systems.
We bring energy-based evaluation of failure and system behaviour into industrial material and component assessment. BioInterfaces transfers this methodology to the biomedical context, strictly non-clinical, strictly engineering.
08 · FAQ
Frequently asked questions
What sets energy-based evaluation apart from classical pull-off and peel tests?
Classical pull-off and peel tests only see the peak force (Fmax), a single point on the load-displacement curve. Two bonds can reach the same Fmax and still behave completely differently: one fails abruptly at the peak, the other keeps redistributing load and fails in a controlled manner.
We measure what happens after the peak. Via the specific dissipated energy GF we capture the full failure behaviour, and with it the difference that determines the clinically relevant stability of an interface.
What does the dissipated energy GF mean?
GF is the specific dissipated energy, derived from the full load-displacement curve. It describes how much energy an interface absorbs and dissipates before complete separation, well beyond peak force alone.
A high dissipated energy stands for ductile, robust system behaviour with high damage tolerance, a low one for brittle behaviour with the risk of abrupt system failure.
Which loading modes do you test?
We test in three loading modes: Mode I (opening, normal load perpendicular to the interface), Mixed Mode I/II (combined opening and in-plane shear) and Mode III (out-of-plane shear, as it occurs under torsional load at modular junctions and screw interfaces).
Which interfaces and systems can you evaluate?
Bone cement systems (cement-bone and cement-implant), adhesive bonds, the bone-implant bond, modular junctions, fixation systems and additively manufactured biomaterials.
Everywhere where it is not the material alone but the interface that drives system behaviour and clinically relevant interface stability.
Who is BioInterfaces for?
For universities and research groups characterising new material classes with energy-based, publication-grade data. For manufacturers of bone cements and adhesives comparing formulations beyond the strength peak. And for implant manufacturers evaluating the interplay of implant, fixation and bone as a system.
How does a project work?
You send us your specimens, we test them and deliver a result report classifying your cement or adhesive system, typically within a few weeks. The evaluation chain runs via the dissipated energy GF including statistical scatter evaluation.
Specimen design, fixtures and the evaluation chain are in place. Standardised metallic substrates, titanium and cobalt-chrome alloys, with defined surface conditions are available. Projects can start as soon as interface pairings and cement or adhesive systems are defined.
Does BioInterfaces provide clinical evaluations or regulatory approvals?
No. BioInterfaces works strictly non-clinically and strictly in engineering terms and is not an accredited test laboratory. Methods, metrics and results serve engineering and interface analysis purposes under controlled laboratory conditions.
Our analysis does not replace medical advice, clinical evaluation or regulatory approval.
What are SampleKits?
Standardised SampleKits let partners prepare their specimens to a defined specification themselves. They make recurring comparison series faster to set up. This keeps specimen preparation reproducible and comparable across all series.
09 · Contact
Let's talk about your interface
Describe your system of implant, bone cement or adhesive including the specimen context. From this we derive a suitable, energy-based method design for the clinically relevant stability of your interfaces.
Connect directly