What-exactly-are-teeth-pz1tvjxkilt2neskdapuokjnigc27ud1223nq47x8g (1)

What exactly are teeth?

Teeth are bone-like structures fixed inside the jawbone and hugged by the gum (gingivae). They have different shapes, but their function is similar; they help us in breaking down food and in forming words.



Are teeth considered bones?

Well, this is a common misconception that people have about teeth. Bones and teeth are made up mostly of the mineral Calcium Phosphate, which make them the hardest structure in the human body; however, they structurally and anatomically differ from each other.

Bones are living tissue that continuously goes into remodeling and regeneration. Anatomically, they contain bone marrow, which produces blood cells, and spongy and cortical bone. On the other hand, teeth are not living tissue and are made up of four different layers. Enamel, dentin, cementum, and pulp.

What are teeth made of?

These are the different parts that make up natural teeth, from the outer to the innermost layer:


is the outermost layer of the tooth; although it may appear yellowish, it is translucent in color, and it only projects the color of the underlying layer (dentin). Tooth enamel is highly mineralized as about 96% of its structure is calcium phosphate, which gives it hardness and brittleness characteristics.


just under enamel, we have dentin that is yellowish in color. It is 70% mineralized; thus, it is softer than dental enamel. Dentin has microscopic channels called dentinal tubules, that radiate from the dentin into the pulp, which makes it highly sensitive to decay. Unlike enamel, dentin is forming throughout our lives.


covers the root part of the tooth and serves as the place of attachment to periodontal tissue to give stability. Cementum is 45% mineralized so it is softer than enamel and dentin. The cementum is normally not visible as it is covered by gum, but in certain cases, gum can recede, exposing the root, and leading to root sensitivity and/or root decay.

Dental pulp

this is the innermost part of the tooth (the core of the tooth), it contains blood vessels and nerves. It is a highly sensitive tissue and when extensive tooth caries reach the pulp, a person would feel severe pain that cannot be controlled by medication and dental treatment needs to be initiated.

What is the difference between baby and adult teeth?

The first set of teeth that we have are a set of baby teeth, then these get permanently replaced by adult teeth. The main function of primary teeth, other than helping children chew food and talk, is to be a placeholder for future adult teeth.

Primary (Baby) teeth

They are 20 in number and the first baby tooth erupts at about six months of age. Baby teeth have thinner enamel than adult teeth; hens they are more susceptible to tooth decay. They are whiter in color and shallower than their successor’s teeth.

Permanent (Adult) teeth

They are 32 in number including the wisdom teeth; they start to come out in the mouth at around 6 years of age. They have thicker enamel which makes them stronger and more resistant to tooth caries. When compared to baby teeth, they have deeper grooves at the chewing surface.

Studies have proven that the state of baby teeth directly affects the condition of adult teeth. For instance, if a primary tooth is lost earlier than it should be, this may delay the corresponding permanent tooth eruption, causing neighboring teeth to drift into this empty space, eventually leading to crowding of teeth.

What can happen to teeth?

As dentists, tooth decay and stained teeth are the most common problems we encounter in the clinic.

Tooth decay

This is when bacteria in our mouth utilizes food debris as a nutrition, as a result, acids are produced. These acids will eventually harm the tooth surface, leading to tooth caries.
Brushing teeth at least twice a day, flossing and going to the dentist regularly can prevent tooth caries, or at least help catch them at their early stages, when simple treatment can still be helpful.

Tooth discoloration

Although a white smile is always advertised, white is not the color of natural teeth. The outer layer (Enamel) is translucent and reflects the color of the underlying layer (dentin) which is yellowish in color. However, many people complain about their teeth being discolored.

As dentists, the first thing we do is assess the cause of these stains, as it can happen with aging, or with certain habits such as smoking or excessive intake of tea and coffee. Additionally, stains can be intrinsic in origin (that means they are part of the tooth structure), many conditions can lead to this such as Amelogenesis Imperfecta.


The takeaway

Teeth have a major role in our lives; they are the first gate of food into our bodies, they help us chew food, speak clearly, and maintain our facial structure. Nevertheless, teeth, like any other organ in the body, if not taken care of, will wear off and cause problems over time; thus, a good oral hygiene routine is vital to keep our teeth and gums in an optimum condition.

Dr. Michael

Dr. Michael

MSc Implantology, Bonn University, Germany