The visible division of the tooth is called the "crown of the tooth" (and indeed the shape of the tooth has an analogy to a crown).
The part that is hidden from the eye and is inside the flesh and the jaw is called "the root of the tooth".
The part that connects the 'tip of the tooth' and the 'root of the tooth' is called the 'neck of the tooth'.
The composition of the tooth
The tooth consists of several layers or layers of pulp.
Tooth enamel or tooth vitreous - is the part that surrounds the tooth in its outermost part. The enamel covering the tip of the tooth is the hardest substance in the human body and its job is to protect the tooth itself from bacterial penetration. When a situation of bacterial growth is allowed in the mouth (by poor nutrition or not brushing properly) the enamel layer is damaged and weakened against the acids that the bacteria secrete, and eventually a hole can form in the enamel layer.
The cementum layer, or tooth cement, is a thin layer (thinner than the enamel layer) that is under the enamel layer and above the dentin layer and its role is to protect the dentin.
Dentin - the dentin layer is a hard layer (having an ivory appearance) that protects the layer below it - a layer tooth fluff.
The tooth pulp - this is the innermost part of the tooth, which is divided into three parts, and consists of many blood vessels and nerve cells, along with soft tissue cells.
when there is a condition of tooth decay (hole in the tooth) which damages the enamel layer and the cementum layer of the tooth only, there is sometimes the possibility of treating it by enriching the area with fluoride and returning the minerals taken by caries to the damaged place, and sometimes a filling by a dentist will be required.
When the caries goes through the dentin layer (depending on the depth and severity) - most of the time the treatment will be either a filling or a root canal.
When the hole expands to the pulp of the tooth, the treatment will usually be root canal treatment, and when the situation is too severe even for root canal treatment - the solution will be to extract the tooth immediately.
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