Depends on what type of teeth if carnivore teeth than they can be similar by both being sharp and used to test through meat but could possibly be different size. or herbivore teeth. can be both a the shape of your front teeth and be different by shape. or omnivore teeth. can be different by the sharp and dull teeth. like in your mouth.
(Let's go with dinosaurs)The two fossil teeth are different because maybe one of the dinosaurs were carnivores or maybe herbivore etc. The way that you can tell if the dinosaur tooth came form an herbivore is by looking at the shape. Herbivore teeth are flat on the bottom. Carnivore teeth is when the tooth is sharp. And of course the different type of dinosaur teeth are used for different matters. Hope the answer was good
