The tip assembly is inserted through any soft tissue to the cortical bone surface.
The user compresses the outer housing, pressing the tip lightly into the cortical bone surface.
At maximum compression (~10N), the tip is pressed into the bone surface enough to set a reference point.
Once the reference point is established the device impacts the tip, driving it into the bone. The distance the tip indents the bone is measured (~150-400µm).
The user moves the tip to a new location about 1-2mm away and repeats the process. The device software instructs the user how many indentations to make.
The entire process is shown here in a simplified animation.
What is OsteoProbe measuring?
OsteoProbe measures indentation distance increase from impact. In other words, how deeply the tip indents the bone.
OsteoProbe is based on the discovery of organic sacrificial bonds and hidden length, or "the glue within our bones." In 2006, Nature Materials published a paper showing how bone can dissipate energy through sacrificial bonds, preventing 'glass-like' fracture and making bone tough. The size and shape of the OsteoProbe tip forces the separation of mineralized collagen fibrils. The deeper the tip penetrates, the easier the collagen fibrils were separated.
How does OsteoProbe compare to other mechanical testing?
The most similar mechanical test to OsteoProbe is a Rockwell hardness test.
Unlike the Rockwell hardness test, OsteoProbe applies the load in a very rapid impact (~14 microseconds). The rapid application of force relative to the mass of the device and the bone allows for accurate indentation depth measurement.
What is Bone Material Quality?
Bone Material Quality is a term that refers to the ability of bone material, which includes mineral and organic components, to function well. Bone material that functions well resists failure for typical forces that a patient experiences. Traumatic fractures are caused by forces that exceed what is typically experienced by a human. Bone fragility is a situation where bone breaks during normal activity (e.g. walking, coughing, falling from standing height, etc.).
For some patient populations, like diabetics or patients on corticosteroids, bone material quality is an important factor for understanding fragility.
What has been discovered?
There have been dozens of publications discussing OsteoProbe in peer-reviewed clinical studies. A list of publications featuring both BioDent and OsteoProbe are available here.