During the dental visit the dentist or dental hygienist will look at all your teeth. They count the teeth in your mouth. To begin, they may count your fingers 

Then the dentist of dental hygienist will count your teeth.

The tooth counter is also called an explorer. The tooth counter feels like a soft tap. You can try it on your finger nail

The dentist or hygienist may count your teeth out loud. Your job is to keep your mouth open big while they are counting.

The dentist or dental hygienist may use the explorer to feel your teeth which can make a funny scratching sound.

In order to see your teeth more clearly, the dentist or hygienist may need to wash and dry your teeth. They may squirt water or air (wind) into your mouth.

Here is a video of the water squirting.

Next, they may need to suck the water out of your mouth. They use something called a straw for that. It works like a little vacuum and takes the water out of your mouth