The best performing lubricants for medical and dental handpieces consist of polyurea-thickened greases using a base of mineral oil or polyalphaolefin (PAO), according to research conducted by GRW High Precision Bearings.
GRW tested 30 lubricants from different manufacturers and identified five autoclave-resistant lubricants most suitable for use in dental and medical products.
Each lubricant was tested to 1,000 sterilization cycles with superheated steam. Initial testing eliminated 11 lubricants. The remaining 19 lubricants were subjected to analytical and visual testing criteria, including weight, optical changes, scanning electron micrographic inspections, and infrared spectra, and five proved capable of withstanding repeated sterilization, the company noted in a press release.
GRW also performed high-speed running tests (such as in dental turbines running at 500,000 rpm), noise, and starting torque behavior tests. These tests revealed that any increase in starting torque caused by viscosity changes in the lubricant resulted in considerable heat generation within each bearing.
Considering all known criteria, these tests revealed the best overall results were achieved using greases with a base of mineral oil or PAO, according to GRW.
