Tyrannosaurus Rex had a U shaped jaw with closely packed teeth at the front. These D shaped teeth curved towards the back making them very strong and prevented them from snapping when T Rex bit and pulled at large pieces of meat. The remaining teeth towards the back were shaped more like bananas and were larger on the top jaw than the bottom. These reinforced teeth made Tyrannosaurus a very effective carnivore who could prey on other dinosaurs and eat them.