University of Alabama at Birmingham
Faculty
Nate Lawson DMD PhD is the Division Director of Biomaterials and the Director of the Biomaterials Residency Program. He obtained his DMD from UAB in 2011 and his PhD in Biomedical Engineering at UAB in 2012. His research focus is the mechanical, adhesive, and optical properties of dental materials.
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Equipment
Keyence VH profilometer
This device can perform an optical scan of an object up to about the size of 50mm. The scans take about 30 seconds. The resolution in the x-y is about 1 micron. And in the z-axis it is ??. Unfortunately, the machine is not helpful in measuring Ra values below 1 micron. The machine comes with built-in analysis software that can volumes and areas. We use this machine mostly for wear testing to measure small divots caused by our wear machine. We can also use the machine to measure the volume of enamel lost after wear testing.
UAB wear testing machine
This is a custom device that can create impact and sliding wear. A 15N load is applied (this load cannot be varied) and then a distance of 1.8mm of sliding occurs. We can mount specimens into brass holders with ??mm circular openings (??mm depth). The antagonist can either be a 2.5mm diameter ball (SS or ceramic ball bearing) or anything that can be mounted into a socket screw hear (ie enamel cusps). The machine accommodates 4 specimens. The test is run in 33% glycerine at room temp. The machine runs for 400,000 cycles for 60-80 cycles/second. The test takes 3-4 days. We have 2 machines but they give slightly different results and both machines are never used for the same project.
Instron universal testing machine
It is equipped with a 5kN load cell. The machine runs on Bluehill 2 software. Bascially, a universal testing machines allows measurement of compressive or tensile forces applied through a moving crosshead. We have fixtures for measuring 3-point bend flexural strength (ceramic/composite or denture), biaxial flexural strength, crown fracture, crown retention, Ultradent shear bond strength, compressive strength, tensile strength