Ergonomic Techniques for Predictable and Accurate Tooth Preparations

Written by: Joseph Blaes, DDS


Have you ever experienced pain in your hand or wrist, a pain that ranges from acute to an ache that never seems to go away? It can lead to carpal tunnel syndrome, hand surgery, and early retirement. Do you know why? We hold an air-driven handpiece by pinching it tightly close to its head. This causes the muscles of the thumb and forefinger to contract over long periods of time.

If you grip your air-driven handpiece like you are going to cut a tooth, you will notice that if you let go of it with your thumb and forefinger, the handpiece will fall backward. When you are prepping with an air-driven handpiece, you are constantly fighting the air hose and you pinch tightly with your thumb and forefinger, which is causing your pain.

Figure 1 shows how dentists hold an air-driven handpiece. The dentist grasps the handpiece in a pinch grip. The thumb and the finger muscles are flexed. This grip leads to hand fatigue and pain at the end of the day. This also leads to musculoskeletal pain, back and shoulder pain, and eyestrain.

Figure 1. An air-driven handpiece pinch grip.

I have been using an electric handpiece for more than 30 years. For 28 of those years, I have been using Bien-Air electric handpieces. A Bien-Air electric handpiece will prep teeth without pain for as long as you want. Now, let me introduce you to Bien-Air’s latest electric handpiece, the NOVA 1:5 MS. This handpiece gives me the constant quiet power to prepare teeth.

The NOVA 1:5 MS Electric Handpiece is pictured in Figure 2. Look at how I hold it in my hand. Notice that the motor and back of the handpiece are balanced on the area between the thumb and index finger. The thumb and finger are not flexed but are merely maintaining the balance of the handpiece and directing the bur on the tooth. I can open my thumb and forefinger and the handpiece stays because it is perfectly balanced. This helps avoid finger pain and wrist fatigue.

Figure 2. NOVA 1:5 MS Electric Handpiece (Bien-Air).

Figure 3. A dentist’s hand is cramping.

Figure 3 is the hand of a 48-year-old dentist, who needs to stop his hands from cramping so that he can pay off his school debt. He posted this photo and issue on Facebook asking for help. Notice the muscles cramped in his finger and thumb. He uses an air-driven handpiece and uses his finger and thumb to pinch the head of the handpiece. The muscles in his hand go into spasm and cramp at any time.

He should use an electric handpiece because it will help him no longer pinch the head of the handpiece and get rid of his hand cramps.

The ADA has published articles warning about electric handpieces causing oral-tissue burns. The NOVA 1:5 MS is the safest in the industry because it is equipped with a heat-arresting, cool-touch ceramic push button that is guaranteed not to elevate above 98.6°F during operation. No more tissue burns.

Constant high torque allows me to precisely prepare the tooth without having to stop to wait for the air pressure to catch up, so there is no feathering. The handpiece simply will not stall. Dentists who switch to NOVA 1:5 MS will find at least a 15% reduction in tooth preparation time.

The NOVA 1:5 MS allows the dentist to complete all restorative work, including the removal of caries, finishing, and polishing at any speed you desire. Bur speeds are variable from 500 to 200,000 rpm, which translates to 60 W of power. With this power, you will experience no slowdown when you apply pressure.

With my Bien-Air electric handpiece, I can practice the 3 Gs: Get in, Get it done, and Get out. My patients enjoy spending less time in the dental chair.

For more information, call Bien-Air USA at (800) 433-BIEN (2436) or visit