Enamel

Synonyms

Substantia adamantina

English: enamel

introduction

The part of the tooth that is visible in the oral cavity is the tooth crown. It is completely covered by tooth enamel and protects the core of the tooth, the dentin. It determines the external shape of the tooth crown. This tooth enamel is the hardest substance in the body and consists of 98% inorganic components, the hydroxyapatite. Tooth enamel is the hardest substance in the human body, so the dentist can only work on it with instruments that are studded with diamond grains.

Since the tooth enamel is not supplied with blood, once destroyed tooth enamel cannot be built up again and is irretrievably lost. Nerves are also absent in the enamel, so that no pain can arise if only the tooth enamel is destroyed in a tooth decay. Only when the carious process reaches the dentin does pain occur, as the dentin is traversed by tubules in which nerve fibers run that transmit the pain to the pulp.

How is tooth enamel built up?

Tooth enamel is the hardest tissue in the human body. About 95% of it consists of inorganic material, which means that there are no living cells, blood vessels or nerves there. It is built up by the ameloblasts at the beginning of life. Then they perish, which is why it cannot be regenerated. It contains a wide variety of elements, including: calcium, sodium, fats and proteins. However, most of it is made up of hydroxyapatite. This is a mineral that contains phosphate, among other things.

In contact with fluorides, fluorapatite can form, which is much harder and less susceptible to external stimuli. This is the basis for the positive effect of daily tooth fluoridation via toothpaste. Furthermore, the enamel is made up of enamel prisms, with the length of the prisms determining the enamel thickness (max. 2.5 mm). The prisms, in turn, are connected by inter-prismatic enamel, which creates high stability.

Tooth enamel cuticle

The upper cuticle of the tooth enamel forms on the surface of the enamel. It is a thin film of organic material that also covers the remaining surfaces in the oral cavity. When you brush your teeth, this coating is removed from the enamel, but it quickly forms again from components of the saliva. The cuticle is completely different from bacterial plaque. It has no ill-making meaning.

Melt formation

Tooth enamel begins to develop in the jawbone before it breaks through Oral cavity. At the breakthrough it is closed. The cells that create enamel are called ameloblasts or adamantoblasts. After the melt formation is complete, the ameloblasts perish because they are no longer needed. During enamel formation, fluoride can be incorporated into the hydroxyapatite. This is possible by giving the children low doses of fluoride tablets. Too much fluoride can lead to so-called fluorosis. This results in discoloration of the enamel, which does not destroy the enamel, but affects the cosmetics. Therefore, the dosage instructions given by the dentist should be strictly followed.

How can you restore tooth enamel?

Tooth enamel is largely inorganic, i.e. "non-living" material.This means that it cannot be built up later by cells. Once the tooth enamel has been lost, regardless of whether it is due to tooth decay, broken teeth or acid-related erosion, it can only be restored by introducing external material.
Today, these materials are mainly tooth-colored plastic. To do this, the caries must first be removed and the tooth must be pretreated with various means in order to create a bond between the two phases. In the past, the silver-colored metal amalgam was more often used for fillings.

In contrast to a carious defect, demineralization must also be mentioned here. This is an acid-related roughness / roughening of the enamel, in which elements are released from the most superficial enamel layer. These can, however, be reintroduced through remineralization, i.e. the reinstallation of the triggered elements. Regular fluoridation helps as it strengthens the tooth enamel.

See also: How can you rebuild tooth enamel?

Toothpaste hardening of the enamel

There are many different toothpastes that harden the tooth enamel through daily brushing. The cause of the hardening is the ingredient fluoride. If this is contained in the toothpaste, the tooth enamel can remineralise and the top layer of enamel can be hardened again every day.

Basically every adult is recommended to brush twice a day with a toothpaste containing fluoride.
In addition, the dental care should be expanded to include the use of a fluoride gel once a week. This is a toothpaste that contains a lot of fluoride and protects the enamel from tooth decay. This is offered by many manufacturers, but Elmex Gelee® is used particularly frequently.

Tooth enamel and tooth decay

Although tooth enamel is the hardest substance in the body, it is not invulnerable. Bacteria in plaque produce acids that attack tooth enamel. Strangely enough, this kind of destruction does not begin on the surface of the enamel, but just below it without the top layer breaking in. In this situation, the process can still be repaired with the help of fluoridation. However, once the surface has been destroyed, the caries continues and can only be stopped with a tooth filling. Sour fruit juices also attack tooth enamel by roughening the surface. If the teeth are then brushed, the roughened layer is removed. Therefore, after consuming sour juices, you should always wait a while before brushing your teeth.

How does tooth enamel break down?

Tooth enamel degradation can take place in a number of ways. Above all, there is the bacterial, carious tooth enamel loss. Plaque build-up on the teeth causes bacteria to settle on the tooth enamel and their metabolic products create ever larger holes.

Furthermore, the acid-induced degradation of tooth enamel should also be mentioned here erosion called. Frequent and, above all, regular acid intake, for example through soft drinks or frequent vomiting, creates a low pH value in the mouth, which triggers ongoing demineralization. The body can no longer regulate this itself due to the long exposure time - tooth enamel is broken down.

Mechanical factors represent a further possibility. This is the breakdown of tooth enamel due to night clenching or grinding of teeth as well as incorrect brushing technique.

What is a tooth enamel disorder?

Tooth enamel disorder is a malformation of the tooth enamel. It can be genetic, as in the case of the Amelogenesis imperfecta. In this case, the enamel-forming cells, the ameloblasts, are missing, which means that there is no tooth enamel and the teeth are severely damaged from the start without any external influence.

But also wrong behavior or malnutrition in childhood can trigger enamel disorders. Especially with overfluoridation, brown stains often appear on the permanent teeth, which are also very prone to caries. Too high a dose of fluoride occurs when children are given fluoride tablets over a long period of time in addition to normal food and toothpaste containing fluoride.

Amalogenesis imperfecta

As with fluorosis, it occurs with Amalogenesis imperfecta also to brown discoloration of the enamel. These are the product of incomplete enamel formation. The cause lies in a mostly hereditary malformation in the enamel formation. The rest of the tooth is normal. Since the malformation is cosmetically annoying, it has to be eliminated by prosthetic measures.

Enamel hypoplasia

Enamel hypoplasia is also a developmental disorder. Whitish spots are embedded in the enamel. Enamel hypoplasia can mainly arise when the calcium balance is not in order. With today's rickets prophylaxis with vitamin D, however, the occurrence of such hypoplasias has become rare. Infectious diseases or nutritional disorders can also lead to hypoplasia of the tooth enamel. From the location of the spots in the enamel, one can draw conclusions about the period of the enamel development at which these disturbances occurred.

Tooth enamel defect

Tooth enamel defects are often the disease Molar Incisor Hypomineralization. It is mostly discovered in childhood and is characterized by a damaged tooth enamel structure and tooth discoloration and the associated brittleness.
Incisors and molars are particularly affected, but milk teeth are rare. The diseased permanent teeth have a creamy-white to yellowish color and their texture is softer and more porous than healthy teeth. This also leads to the fact that the teeth react very sensitively to external stimuli such as hot or cold. Dental hygiene becomes a problem as it can no longer be performed without pain.

According to current studies, the cause has not yet been fully clarified, so far it is only known that the phosphate content in the tooth enamel of sick people is lower than normal. If this disease is not treated, parts of the teeth can flake off even under normal stress. Then caries develops quickly.
Depending on the severity of the disease, treatment is carried out using local fluoridation measures, fissure sealing, fillings or crowning of the affected teeth.

However, tooth enamel that has developed normally can also have defects. Softening by acid, abrasion by grinding teeth or caries lesions leave structural defects.

Pain in the enamel

Tooth enamel pain is extremely atypical, as tooth enamel is not a living substance. Sometimes, however, cell processes radiate into the enamel from inside the tooth. Then even minor enamel defects can be very painful.
However, dark fissures in the molars are often more problematic. Mostly one thinks that it is only a small discoloration of enamel or caries, but under the fissure there is a large hole that is not visible to the eye, which has already hollowed out the tooth and thus causes severe pain.

You might also be interested in: Causes of Toothache

Summary

The enamel covers the surface of the tooth crown and protects it from external influences. It is the hardest substance in the body and consists of 98% inorganic substances, hydroxyapatite. It owes its origin to the adamantoblasts. Disturbances can occur during the development phase, which later lead to color changes in the enamel. Acids attack the tooth enamel and lead to its destruction. Fluorides can reduce the solubility of tooth enamel.