An expert in dinosaur teeth from the Museum of Natural History in New York City explains that paleontologists can identify a dinosaur as either a carnivore, herbivore, or omnivore by the shape, size and structure of the teeth. The number of rows of teeth, called batteries by paleontologists, depends on how quickly the dinosaur needs to chew its food.
The teeth are all paleontologists have to work with since the outlines of most dinosaurs are impressions on the rock. Dinosaur teeth look like pebbles until you measure them and compare them to other fossils.
Different types of dinosaur teeth can be difficult to tell apart. A paleontologist can tell them apart because no two species share a tooth pattern. Dinosaur teeth were sometimes lost or broken off, so finding a whole or nearly whole tooth is very helpful for identification.
Characteristics of Dinosaur Teeth
Teeth have their unique anatomy and contain enamel, dentin, and cementum. They are hard, dense, and dentin that grows in the form of cone-shaped cylinders. Each of these “columns” has a nerve that runs through the center. A hard, white substance, called enamel, covers the crown of a tooth. It makes up about 85% of the tooth’s structure.
Dentin is the hard, calcified tissue underneath the enamel. It makes up most of what’s left after subtracting the portion taken up by enamel. Cementum is a thin, bonelike substance that covers the roots of teeth.
The number, size, shape, and structure of dinosaur teeth were unique to each species of dinosaur. Scientists sometimes find fossilized soft tissue with dinosaur fossils. It can help paleontologists identify the specimen. Although dinosaur teeth are usually described as straight or hooked, they almost always had some curve.
Most dinosaurs had serrations on their teeth. Serrations increase cutting power and tooth life by dividing wear on the edges among many serrated points rather than concentrating all on the edge of a single tooth surface.
Check The Shape Of The Tooth Crown
The shape of the tooth crown helps categorize the teeth because these structures have very specific functions. A good example is the most common dinosaur teeth, which scientists call “bunodonts.”
A large, bulb-shaped cusp characterizes bunodont teeth with a small point at the end. Scientists found this dentition in herbivorous dinosaurs like hadrosaurs (duck-billed dinosaurs), ankylosaurs (armored dinosaurs), and ceratopsids (horned dinosaurs such as Triceratops).
What are these different shapes doing? The primary function of a bunodont tooth is to crush, grind and tear up tough plant matter that is difficult to digest. The size, shape, and number of cusps on a bunodont tooth vary depending on the plant matter that it’s chewing. There are many ways to determine what dinosaurs ate based on their teeth.
Look At The Size Of The Tooth Crown
Paleontologists have a few different ways of identifying dinosaurs. The first step is to identify where the dinosaur lived. Understanding the size of the crown helps scientists group fossils together.
Scientists said that the tooth crown size could tell you a lot about a dinosaur, like if it was an herbivore or carnivore. The size of teeth is an important clue to the feeding habits of dinosaurs. By studying the size of a dinosaur’s teeth, paleontologists can understand how fast the dinosaur grew to adulthood. Scientists use tooth size to differentiate between species.
They also use teeth to determine how long a dinosaur lived and what generation it belonged to. The conclusion that many paleontologists have come to is that large dinosaurs had smaller teeth than small dinosaurs.
Observe The Angle Of The Tooth Crown To The Root
Dinosaur teeth are as individualized as fingerprints, making them incredibly useful for paleontologists. Paleontologists also measure the angle of a tooth’s crown to its root, with carnivores and herbivores each having distinct angles.
Scientists calculate the angle as the angle formed between a line drawn through the highest point of the crown and a line drawn perpendicular to the surface where the tooth emerges from the jaw. The angle of a tooth crown relative to its root can help distinguish between different species.
A small angle between the teeth is evidence that the serrations are small. You would find them on a meat-eater. A large angle indicates that it was from a plant-eater whose teeth were more like leaves and were less serrated.
In most cases, this angle is approximately 45 degrees for many dinosaurs. This finding helps scientists identify new dinosaur species without much trouble.
Determine How Many Teeth Are In A Line Across The Jaw
The number of teeth was an important factor in determining what kind of plant or animal the dinosaur ate, how much food it needed to eat, how fast it moved, and even the purpose of its teeth.
Scientists count the number of teeth in a line going across the jaw. They identify whether the teeth are in rows straight across or in zigzag patterns. They look for gaps in the line of teeth. Gaps can be spaces between the rows of spaces within each row.
The best way to get this information without having a whole jaw intact is through CT scans. This process is simple, with the flat-bed scanner taking detailed images at high speeds. It can reveal density and texture and even color in the tooth.
The scan creates a 3D image in which scientists can identify teeth, jaws, and possible bite marks. CT scanners use X-rays or other ionizing radiation to produce cross-sectional images of the inside of an object.
To create a CT scan, scientists need to position the fossil in the center of the scanner and rotate it around its axis while taking X-ray images at different angles. The scanner will then create a 3D model based on all these angles and reconstruct it into one image that looks like your fossil from every angle.
Dinosaur teeth are like human teeth in that they have a crown and root. They differ because they don’t have enamel—it’s usually dentin or cementum. The name for these types of teeth is “polyphyodont,” meaning multiple growth cycles. For example, humans only grow one set of teeth in our lifetime, whereas birds can grow many sets throughout their lives.
When we look at fossilized remains from dinosaurs, we can determine how many times a dinosaur had grown new teeth by counting the number of lines across the jawbone where we can see tooth replacement.
Examine How Close Together Teeth Are In Their Sockets
Paleontologists who study fossil teeth can learn a lot about the type of dinosaur by observing how close together the teeth are in the jaw. The distance between the teeth, or the spacing, varies from species to species.
Most reptile skulls have wide sockets and very large spaces between each tooth. Dinosaurs had a much more varied range of tooth size and spacing. There are three common types of tooth spacing exhibited in dinosaur fossils:
- Dinosaurs with closely spaced teeth without interlocking serrations usually indicate that they are herbivores. Herbivores have blunt, flat teeth for crushing plants. They also have ridges for grinding up tough vegetation like grasses and leaves.
- Dinosaurs with wider-spaced teeth with interlocking serrations usually indicate that they are carnivores. Carnivores have sharp, blade-like teeth for snagging and slicing meat. They also have serrations akin to steak knives for sawing through flesh.
- Irregular spacing on the jaws, sometimes with interlocking serrations, indicates omnivores. They have teeth that are both sharp and flat. They use their sharp teeth to cut and chew their food while their flat teeth grind it up.
A plant-eating dinosaur has many small teeth that sit tightly together. This arrangement helps dinosaurs scrape and grind tough fiber, such as leaves and grasses. Research shows that plant-eating dinosaurs also had teeth with complex enamel folds, which extend down into the tooth. The folds give the teeth extra strength. When paleontologists find this type of folding, they know they have discovered a plant-eating dinosaur rather than a meat-eater.
The closely packed nature of the teeth means that they would be able to bite through tough flesh and grind and tear up meat. Allosaurus and Dilophosaurus had sharp serrated teeth that were close together. They may have to prey on large animals, for example, a sauropod dinosaur. 
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Study The Wear Patterns On The Periodontal Ligament, Which Attaches To Teeth And Gums
Paleontologists looked at the periodontal ligaments of dinosaurs and modern animals and found them very similar in structure. The periodontal ligaments stretch and contract with the movement of the jaw, causing them to become weaker. Any wear patterns on the tooth will also be present in the ligament.
The paleontologist first examines the wear pattern on the tooth, which is the most important indicator of what a dinosaur ate. The next thing a paleontologist will do is determine if a layer of periodontium still covers the root of the tooth or not. An older dinosaur would have a root free of the periodontium, while a younger dinosaur would have a still covered root.
There’s plenty of evidence that suggests that dinosaurs chewed differently than mammals. A carnivorous dinosaur’s teeth are much more delicate than you might expect. They didn’t need such strong teeth to tear through tough skin or chomp through bone as modern-day carnivores do. They would have been able to kill smaller prey with one bite.
Scientists must identify whether a fossilized tooth comes from an herbivore, carnivore, or omnivore — and what kind of dinosaur it came from. They can then use this information to learn about entire ecosystems during the Jurassic and Cretaceous periods.
Find Out What Types Of Food They Ate
Dinosaur teeth are great tools for scientists. They give us a glimpse into the diets of dinosaurs and help identify whether the extinct animals were meat eaters or plant-eaters. Most modern-day carnivorous mammals have pointed teeth for killing and tearing, but herbivores have blunt teeth for grinding plant material.
- Tyrannosaurus rex had a mouth full of sharp, serrated teeth that could crush bone and tear flesh.
- Brontosaurus was a gentle giant with peg-like teeth suitable for ripping leaves off trees and shrubs.
- Velociraptor’s long, curved claws and sharp teeth were excellent for ripping into prey. They had dozens of teeth in their jaws, almost like a comb.
- Baryonyx was a fish-eater with long, thin teeth adapted for catching slippery prey.
- The large incisors common among sauropods may have helped them tear or grasp their tough, fibrous diet of plants.
- Stegosaurus had spoon-shaped teeth, suggesting that this plant-eater may have removed leaves and flowers from trees and shrubs.
- Allosaurus had nasty-looking teeth with serrated edges and was probably a predator.
- Duckbills are omnivores, which means that they eat both plants and animals.
- Iguanodon jaws show large, spade-shaped teeth that they used to strip leaves from trees.
Looking at what a dinosaur ate can teach us about its lifestyle and environment. Dinosaur teeth can also tell us a lot more than just how dinosaurs chewed up their food. They can help us figure out what they ate and looked like.
Final Thoughts
The greatest thing about dinosaur teeth is that they help paleontologists reconstruct dinosaurs as living, breathing creatures. By studying a single tooth, they can learn what a dinosaur was eating and how quickly it grew.
Studying these isolated teeth allows scientists to discover even the smallest peculiarities, anomalies, and individual traits. From this information, paleontologists can better categorize species. Scientists can understand dinosaurs species’ evolutionary timelines better and with greater precision.
If paleontologists can identify the piece of an animal’s jaw or skull that the tooth came from, they can even get an idea of what its face might have looked like. Dinosaur teeth are important to paleontology because they are precious puzzle pieces that help us combine dinosaur history.
