Teeth vs Bones: Differences and Similarities
Updated: Oct 14, 2022
We've been taught that calcium is crucial for building strong bones and teeth but are teeth bones or are they something completely different? What makes them different and what makes them the same? Our long island city dentists will explain it all for you.
Table of contents:
Are teeth bones?
Teeth are not considered bone because they don't serve the same functions. First of all, teeth are used for mastication which means chewing and eating. They also provide shape for your face and lips. Without teeth, your face would collapse inward.
Bones are used for eating but rather for structure and support of the body. They're also used for protecting various organs of the body. Last but not least, they permit human locomotion by letting muscles attach to them. When the muscles pull on the bone, the body moves.
What are teeth made of?
Teeth are mainly composed of hydroxyapatite with some collagen and connective tissue in various layers of the teeth. Depending on the layer, the ratio and composition of these components will differ.
Your teeth are made of 4 different types of tissues.
Enamel. Your enamel is the hardest substance in your body, it is even harder than bone because it is composed of 96% of hydroxyapatite. The last 4% are made of water and organic matter.
Dentin. This is the layer underneath the tooth enamel and it is softer. It is composed of 70% hydroxyapatite, 20% organic materials, and 10% water by weight. The organic component does have collagen in it.
Pulp. The innermost layer of the tooth is filled with soft connective tissue. It also contains the nerve and blood vessels, which keeps the tooth alive.
Cementum. This layer only covers the root of the teeth and it is about 45% hydroxyapatite, 33% organic material (collagen) and 22% water.
Teeth are actually the hardest substance in the human body due to its hydroxyapatite concentration!
Are teeth alive?
There is a misconception that teeth aren't alive but that isn't true. Teeth are technically mostly alive with the exception of the enamel, which is not alive. The enamel is made of mostly inorganic matter, hydroxyapatite so it does not have any nerves or blood supply going to it. The rest of the layers of the teeth, the dentin and pulp are definitely alive.
We can prove to you right now whether or not your teeth are alive. Dead teeth have no feelings or sensations, which means if you drink something cold it won't feel anything. Teeth that are alive will feel the cold. Consequently, if you've ever needed a root canal due to unbearable pain you'll know what I'm talking about. Once your dentist removes the nerve from the tooth, it is considered no longer alive and you'll also no longer feel anymore pain.
Dead teeth also look different from healthy teeth that are alive because the dead ones look grey. This phenomenon is the same as humans who have died because once they do they start turning grey. All of that pink from the blood gets drained out of their body.
Therefore, if you ever come across information online about teeth not being alive, you'll know that is completely false. Teeth are mostly alive with the exception of the enamel layer.
Are teeth organs?
Teeth are organs because they're considered an ectodermal organ. This puts them in the same category as hair, skin, sweat glands, and salivary glands. Basically everything that is located near the outside surfaces of the body.
What are bones made of?
Bones consist of 30% flexible matrix that is interwoven with about 70% of bound minerals. This unique composition gives bone their hard and strong yet flexible properties.
Bone matrix. The matrix is mostly made out of elastic collagen fibers, approximately 90-95%. This extracellular matrix is considered the organic component of bone.
Bound minerals. This is the inorganic component of bone and it mainly consists of hydroxyapatite, which is the dominant bone mineral. It is composed of a lot of calcium.
Bones are considered living tissues and they are one of the organs of our body. They are a specialized type of connective tissue that also has the ability to repair itself when damaged. It is able to do this because it is considered alive.
In fact, your bones constantly remodel throughout your life. Old bone gets broken down and replaced by new bones. It is able to do this with the help of specialized cells called osteoblasts and osteoclasts.
Osteoblasts help build bone and deposit new bone.
Osteoclasts help to break down old bone and resorb them.
It is due to this remodeling function that your bone is able to repair itself and heal. The injured parts get broken down by osteoclasts and then it gets repaired by the osteoblasts which deposit new bone.
Despite your bones not being as hard and strong as teeth, the strongest bone in your body is the femur. It needs to be in order to support the entire weight of your body on your legs!
Your bones contain marrow which can produce red blood cells and white blood cells. A lot of blood vessels pass through the marrow.
Similarities and differences
Despite teeth not being bone, they do share a lot of similarities. Although they have enough differences that they are recognized as different types of tissues.
What they have in common
Both your teeth and your bone contain a lot of calcium.
They're both very strong and hard.
They're both alive.
What is different about them
Only your bones are able to self-regenerate and repair itself.
Your teeth can get cavities.
Teeth are used for eating.
Bones are used for support and movement.
Teeth don't have a periosteum.
The Verdict: Are teeth considered bones?
Unfortunately your teeth are not bone because they serve completely different functions. They do have some similarities such as containing a lot of calcium. The one good piece of news about that is that your bones can't get tooth decay. Imagine if you had a cavity in your arm and it needed a filling. That would not be pleasant at all.
Nonetheless, don't forget to keep up your oral hygiene routine to keep your mouth nice and healthy because your teeth can get cavities. Brush twice a day and floss before you go to bed. Last but not least, you should get your dental check up every 6 months.
Author: Written by Dr David Chen, a long island city dentist.