How a tooth is built

The crown is the part you see. It is coated in enamel, the hardest substance in the body, made mostly of mineral. Enamel does not contain living cells, so it cannot heal a chip the way bone can.

Under the enamel is dentine, a yellowish tissue that is also mineral but softer, with tiny tubules. It is sensitive. If enamel wears or a cavity reaches it, heat and cold travel those tubules toward the nerve.

The layers

The pulp, in the centre, holds blood vessels and the nerve. It enters through the tip of the root. A knock or deep decay that inflames the pulp is why a tooth can throb. The pulp is the living part.

The root sits in the jaw, held by a ligament and surrounded by cementum, a thin bony coat. Gum covers the neck of the tooth. The jaw bone anchors the root. A tooth is not stuck on like a sticker.

Two sets, then one

Children grow a first set, often called milk teeth, which make space and then fall out as permanent teeth push up. Adults normally have thirty-two permanent teeth if the wisdom teeth come through, fewer if they do not.

Bacteria in plaque feed on sugars and make acid. Acid dissolves mineral from enamel. Brushing away the film, and not bathing teeth in sugary drinks, is the practical consequence of that chemistry. A dentist repairs what the mouth cannot rebuild.

The layers

A tooth is a layered tool. Enamel covers a bony body, and a living core sits inside. The crown is the part you see. It is coated in enamel, the hardest substance in the body, made mostly of mineral.

Put those two statements side by side. The first sets the condition. The second says what happens once that condition is met. How a tooth is built needs both. Drop the first and the second has nothing to explain. Drop the second and the first is only the scene.

Two sets, then one

It is coated in enamel, the hardest substance in the body, made mostly of mineral. Enamel does not contain living cells, so it cannot heal a chip the way bone can.

The order is the explanation. What the first sentence names has to be there before the result in the second sentence can show up. The piece does not ask you to accept the result first and hunt for a cause afterwards.

A check you can make

Enamel does not contain living cells, so it cannot heal a chip the way bone can. Under the enamel is dentine, a yellowish tissue that is also mineral but softer, with tiny tubules.

A fair check is sequential. Confirm the first statement. Then see whether the second is the result of it, rather than a separate fact parked in the same piece. If the result shows up without the condition, this account does not cover what you are looking at.

The limit of the claim

Under the enamel is dentine, a yellowish tissue that is also mineral but softer, with tiny tubules. It is sensitive.

The two statements do different jobs. One says what is there, what it is made of, or what acts on it. The other says the change that follows. The title names the change. It is not an inventory of parts.

The same steps, in order

It is sensitive. If enamel wears or a cavity reaches it, heat and cold travel those tubules toward the nerve.

Nothing in the second statement cancels the first. It carries the first forward or marks the limit of it. Remember only the result, and the cause goes missing. Remember only the cause, and you will not know what the piece says happens next.

Why the order matters

If enamel wears or a cavity reaches it, heat and cold travel those tubules toward the nerve. The pulp, in the centre, holds blood vessels and the nerve.

Read them as one path. Start at the first full stop and do not skip to the outcome. The words between the two statements are the mechanism. The title is the name of that path, not a second claim.

Condition, then outcome

The pulp, in the centre, holds blood vessels and the nerve. It enters through the tip of the root.

The first statement can be true and still not finish the job. The second statement is the job finishing. Hold both, and the paragraph above stops being a list. It becomes the reason the title is worded as it is.

What the title is naming

It enters through the tip of the root. A knock or deep decay that inflames the pulp is why a tooth can throb.

If you wanted a shorter version, it would be those two sentences and nothing else. Everything added around them is there so the dependence is obvious: the second does not happen unless the first has happened.

What has to come first

A knock or deep decay that inflames the pulp is why a tooth can throb. The pulp is the living part.

Put those two statements side by side. The first sets the condition. The second says what happens once that condition is met. How a tooth is built needs both. Drop the first and the second has nothing to explain. Drop the second and the first is only the scene.