Boca Bearings has an assortment of ceramic hybrid dental tool bearings. Dental tool bearings are designed for high speed and reliability. Hybrid bearings have steel races and Si3N4 ceramic balls. Silicon Nitride (Si3N4) Ceramic Balls are formed from a new material suitable for applications where high loads, high speeds and extreme temeratures are factors. Silicon Nitirde is non-porous, non-magentic, non corrosive, lighter than steel and, in ball form, is harder than steel. Because ceramic balls are non-porous they are virtually frictionless and are capable of spinning faster than steel balls.