He is listening to music using Bluetooth.

My gums hurt.

His teeth have strong dentin, making them less prone to cavities.

Toothed whales are a type of marine animal, and as the name suggests, they have teeth.

When he eats an apple, he uses his incisors to bite it off.

He is brushing his upper teeth.

He is conducting research on the radula of mollusks.

He died young.

He is dedicated to the study of the dentary bone.

He likes to take a walk in the park at dusk.