City & Guilds Level 3 Diploma in Dental Nursing Practice Test

The friction grip is the correct answer because it is specifically designed to secure rotary instruments in high-speed handpieces, which operate at significantly higher RPMs (revolutions per minute) compared to low-speed handpieces. This grip provides a stable hold on the bur, preventing slippage during use due to the forces generated at high speeds.

High-speed handpieces often use burs that feature a smooth shank design allowing them to be tightly held in place through friction, ensuring precision and control while performing procedures such as cavity preparation or tooth polishing. The design of friction grip burs, which may not have any locking mechanism, relies solely on an interference fit that secures the tool within the handpiece when engaged.

In contrast, the latch grip is utilized for low-speed handpieces, which use a different type of bur design featuring a notch for securing the instrument. The other types of grips, such as suction grip or direct grip, do not pertain to the method of securing tools in high-speed handpieces, making them not applicable in this context.