This is a story no one really wants to hear, but we will tell it anyway, and you will not soon forget it.

People would rather not talk about dentists and dentistry, so why bother about hygiene in dental surgeries?
Everything looks so clean and high-tech and money apparently does not play a significant role.

Dentists look like surgeons now, wearing masks and gloves, and aren't they
permanently monitored by our governmental health authorities like cooks and butchers?


Masks and gloves are indispensable when fighting cross-contamination.

Never visit a dentist who works without gloves.

But when gloves are used incorrectly they only protect the dentist and not you.
Gloves are useless when you pick up the phone, shake hands
or open a door while wearing them.

Gloves can be a perfect way to spread bacteria throughout the entire surgery.


You might get that opportunity if your dentist has to pick up the phone.
When you are lying in the chair, there is usually a small chart with a dashboard-like instrumentpanel to your right. (It might also be a cranearm that is swinging invitingly above your head )

From this dashboard emerge at least:

- two drills (a fast and a slow one),
- a syringe for an air/water spray,
- a slim pen-like device ( to remove plaque)
- and a torch producing an extremely strong blue light.

At your left ( the assistant's place ) there is generally a smaller instrumentpanel with a large and a small suction pipe.
Let's have a closer look at all these devices.


The high-speed drill or airotor is beyond any doubt the most fearful weapon out of a dentist's armory. It is air-driven, makes about 400.000 rpm. and produces a dreadful sound.
A drill running that needs cooling water to prevent burning.

The water used for cooling is heavily contaminated in many dental surgeries.

High-speed drills are basically small turbines driven by compressed air.
When a dentist stops drilling, he first stops the airpressure.
The little turbine in the drillhead (still in the mouth) will spin a couple of seconds before it stops. This spinning has unpleasant consequences:
A spinning turbine without compressed air will become a pump.
It has been found that moisture from the mouth ( possibly containig saliva or blood ) is sucked back into the drill head about one inch.

The last Dutch Healthcare Inspection showed that :

83.5 % of all dentists interviewed did not clean, sterilise or disinfect these drill heads according to the official guidelines.

( Dutch Healthcare Inspection report " Infection-prevention in Dental Offices May 1998 " )

If a dentist only cleans the surface of these drill-heads, the sucked up material will be expelled into the next patient's (or your) mouth.

Cooling- and spray water in dental equipment often contains ten thousand times more micro-organisms than our domestic tap-water. ( visit -links)

Later we will discuss the problem of contaminated water in dentistry in more detail.


The low-speed drill is usually powered by an electric motor. The drill itself is clamped in a pen-like device. We call them handpieces.
These handpieces contain gear boxes; they are constructed of cogwheels that become extremely dirty doing their job.

These handpieces (like airotors) are hardly ever cleaned, sterilised or disinfected according to the official guidelines. Electric motors themselves cause trouble as well. Each time a dentist changes a handpiece, the electromotor is gripped and thus contaminated.
During a patient's treatment these contaminated motors are constantly placed back in their holes on the instrumentpanel.
Contaminated motors make contaminated holes. That delivery-hole will, in turn, be able to contaminate the motor you are treated with.


Water-air syringes can deliver a stream of water, a stream of air or, when combined, an air-water spray.
They are all used to clean the work area.
Most syringes have two mechanical valves to operate them.
These valves are literally covered with saliva and blood during the patient's treatment.
Syringes are extremely difficult to clean. Most syringes cannot be removed to be cleaned,disinfected or sterilised.

Last but not least:

Syringes often contain heaters to produce a comforting warm-water spray. But unfortunately exactly those temperatures in wich Legionella bacteria families thrive.


Plaque can be removed by a small vibrating chisel in a process called ultrasonic cleaning.
Ultrasonic means literally that you can't hear it, which is a lie because the device makes a dreadful screeching noise.
The chisel must be cooled by water, producing an enormous waterspray.

When this cooling water is contaminated it will produce a contaminated spray, just at the gateway to your respiratory system: your mouth.


This blue torch is used to harden modern resins like filling-materials and glues. Its blue light is not really dangerous but you should not look directly at the beam.
The device with its on-off switch is not easily cleaned.
The glass-rod that produces the blue light can and should be sterilised between each treatment.