Enamel: The strongest structure in the body!

Each tooth structure consists of 3 main components: enamel, dentin, and pulp. Enamel is the outermost layer, plays a protective role and is also the strongest component. Although strong, it can still crack, chip and be dissolved by acids. This is the reason leading to many common oral conditions such as: tooth decay, tooth wear, fluorosis, etc. To have strong teeth, we must protect the enamel layer permanently.

>> Is dentin important? Dentin is a structure just as important as the two components above. Dentin contributes a lot to color, supports tooth structure, as well as contributes to the transmission of stimuli and creates a protective layer for the pulp.

content

• 1/ What is tooth enamel?
• 2/ Composition of tooth enamel
• 3/ Physical properties of tooth enamel
• 4/ The role of tooth enamel
• 5/ Problems with tooth enamel

1/ What is tooth enamel?

Enamel is the thin layer of acellular tissue that covers the outside of the tooth. This crust is the hardest tissue in the human body. Enamel covers the entire crown surface visible in the mouth. Since enamel is almost transparent, light can pass through. The new dentin is responsible for the color of your teeth no matter what color it is: white, gray or yellow.

Sometimes the use of colored foods such as coffee , tea, red wine, fruit juices and tobacco can stain enamel. Therefore, you need to visit your dentist regularly for cleaning and polishing. This removes most surface stains and ensures healthy teeth.

2/ Composition of tooth enamel

• Mineral

Yeast is the most mineralized and hardest in the body. The main ingredients are calcium and phosphate, accounting for 99% by dry weight. By volume, crystals of calcium hydroxyapatite make up 80-90%. The remaining 10-20% is liquid and organic matter.

• The protein

There is a difference between the immature enamel in the fetus and the developing, mature enamel. In fetal yeast, the highest relative composition is; glutamic acid, proline, histidine. While in mature and maturing yeast are asparic acid, serine and glycine.

Protein, the main component of the enamel, is highly concentrated in the grooves, along the enamel junction and in the cervical region. In these regions, the amount of inorganic matter is also reduced correspondingly.

• Country

Forms hydrate shells around crystals and in protein composition

• Trace elements:

Elements such as: vanadium, manganese, selenium, molybdenum, strontium may play a role in inhibiting tooth decay.

Fluorine is normally present in tooth enamel in variable amounts. The highest concentration is always at 50um of the outermost enamel layer. This zone contains about 300-1200 ppm or higher. The deeper layers have up to 20 times less fluoride content. Fluoride content varies according to factors such as: content in drinking water, amount of fluorine penetrating from food, toothpaste; age factor; tooth surface; the presence of wear surfaces; Materials used…

• Structure of enamel crystals

The inorganic component of tooth enamel is mainly calcium hydroxyapatite mineral crystals. Hydroxyapatite (HA) has the chemical formula Ca10(PO4)6(OH)2 is a collection of calcium, phosphate and hydroxyl ions arranged repeatedly to form a crystal lattice structure.

Each atom in the HA crystal can be replaced by another atom. For example, the position of the hydroxyl group can be replaced by fluorine, calcium is replaced by Na, Mg, Zn, etc. When F substitutes for the hydroxyl, the crystal becomes fluorapatite which is more resistant to acids that cause caries.

3/ Physical properties of tooth enamel

The method of enamel formation and the composition of the mature enamel determine the physical properties of the enamel.

•  Thickness :

The enamel covering the crown of the tooth varies in thickness. In permanent teeth, the thickness ranges from a few microns at the neck to 2.5mm at the incisal margin and apex. Thickness also varies with tooth surface and teeth together.

• Stiffness:

Tooth enamel is the hardest and most brittle part of the body. (Mohs Hardness: 5-8, Knoop Hardness: 260-360, Vickers Hardness: 300-430). Corresponding to the degree of mineralization, the surface enamel is harder than the inner layer

• Color:

Enamel clear, slightly bluish-gray-yellowish. Tooth color is determined by the thickness of the enamel layer, the light yellow color of the ivory and the degree of transparency and uniformity of the enamel.

• Permeability:

Yeast has limited permeability. Colorants can penetrate both from the external environment and from the pulp side through the dentin enamel junction. After teeth erupt, enamel becomes less permeable, less porous, and increases in strength.

4/ The role of tooth enamel

Enamel helps protect your teeth during everyday activities like chewing, biting, etc. Although enamel is a hard protector of teeth, it can still chip and crack. Enamel also helps insulate teeth from heat and chemicals that can cause tooth pain.

Unlike broken bones that can be repaired by the body. Once a tooth is broken or the enamel is cracked, the damage is permanent. This is because enamel has no living cells, and the body cannot repair it when it is chipped or cracked.

5/ Problems with tooth enamel

5.1/ Tooth decay

Tooth decay is a condition that occurs when bacteria in the oral environment work to break down sugars to create acids. High acidity will cause surface demineralization of enamel. If this mineral loss is not rebalanced, holes will form in the enamel surface. Advanced caries can destroy enamel and dentin, causing irritation and infection of the pulp. Therefore, it is necessary to treat tooth decay early when detecting and taking preventive measures against tooth decay .

5.2/ Wear of teeth

Tooth erosion occurs when acids erode tooth enamel. The cause of tooth wear can also be due to:

• Excessive soft drink consumption (high levels of phosphoric and citric acids)
• Fruit drinks (some acids in fruit drinks are highly corrosive)
• Dry mouth or low saliva flow (xerostomia)
• Diet (high in sugar and starch)
• Gastroesophageal reflux disease (GERD)
• Gastrointestinal problems
• Medicines (antihistamines, aspirin)
• Genetics (inherited conditions)
• Environmental factors (friction, wear, abrasion)

Types of tooth wear: 

• Brushing: This is natural tooth friction that occurs when you grind your teeth, often unintentionally during sleep.
• Abrasion. This is the physical wear and tear of the tooth surface that occurs when brushing too vigorously, flossing incorrectly, biting on a hard object (such as a fingernail, bottle cap, or pen) or chewing tobacco.
• Corrosion lesions in the cervical region: occur in the cervical region due to bending force 
• Corrosion: occurs due to acids acting on the tooth surface: certain medications such as aspirin or vitamin C tablets, highly acidic foods, GERD and frequent vomiting caused by bulimia or alcoholism.

Saliva plays an important role in keeping teeth healthy. Not only does it increase the health of body tissues, it also protects yeast with calcium and other minerals. Saliva also dilutes corrosive substances such as acids, removes waste from the mouth, and strengthens protective substances that help fight bacteria. However, when you eat a lot of acidic foods, this strengthening process on the teeth no longer occurs.

 What are the signs of enamel wear?

Signs of enamel wear can vary, depending on the stage. Some signs may include: 

• Sensitive. Certain foods (sweets) and the temperature of foods (hot or cold) can cause a pain in the early stages of enamel wear.
• Color change. When enamel wears down and more dentin is exposed, teeth can appear yellow.
• Cracks and chips. The edges of the teeth become coarser, uneven, and jagged as the enamel wears down.
• Pain. In the later stages of enamel erosion, teeth become extremely sensitive to heat and sweets. You may feel more pain.
• Indentations appear on the tooth surface.

When tooth enamel is worn down, teeth are prone to decay. Small cavities can cause no problems at first. But as cavities grow and invade the tooth, they can affect the pulp, leading to an extremely painful abscess or infection.

5.3/ Fluoride infection

Although fluoride is very helpful in preventing tooth decay. But too much fluoride can cause problems like enamel fluorosis. This condition can occur in children and causes defects in the enamel of the teeth.

Fluorosis in children can be caused by: having received too much fluoride through supplements, or drinking water. In addition, swallowing fluoride toothpaste increases the likelihood of enamel fluoridation.

Most children with enamel fluorosis have a mild condition that is not cause for concern. However, in some severe cases, teeth become discolored, pitted, and difficult to keep clean.

5.4/ Yeast hypoplasia

Enamel hypoplasia is the incomplete formation or defective enamel structure during the forming phase, leading to a deficiency in the amount of enamel. 

There are two basic types of enamel hypoplasia:

Hereditary yeast hypoplasia, also known as “infectious yeast production”

There is a disruption of the mesoderm in the embryonic stage of enamel, affecting only the enamel, the endodermal components still develop normally. The disease can affect both baby teeth and permanent teeth. 

There are 3 types of hereditary enamel hypoplasia, which are:

• Yeast hypoplasia: abnormality occurs in organic framework formation
• Poor mineralization: abnormality occurs in the mineralization of organic frameworks
• Under-Maturity: Abnormalities occurring during the maturation of the organic framework

Enamel hypoplasia due to environmental influences: environmental factors affect enamel-producing cells, which can affect both baby teeth and permanent teeth. Both dentin and enamel are affected to varying degrees.

Manifestations:

In people with enamel hypoplasia, the enamel often forms insufficient thickness. Enamel is soft, thin, and fragile, exposing the underlying dentin layer. Enamel hypoplasia will reduce the chewing function of the teeth, causing numbness when eating. In addition, the tooth surface appears milky white spots that turn yellow or the teeth are mottled with black, affecting the aesthetics.

6/ How to prevent tooth enamel loss?

To prevent enamel wear and keep teeth healthy, be sure to brush, floss, and rinse with a fluoride mouthwash and antiseptic daily. See your dentist every six months for regular checkups and cleanings. You should also try the following:

• Eliminate highly acidic foods and beverages from your diet such as carbonated sodas, lemons and other fruits and juices. Rinse mouth immediately with clean water after eating acidic foods or drinking acidic beverages.
• Use a straw when you drink acidic drinks. The straw pushes the liquid to the back of the mouth, avoiding contact with the teeth.
• Reduce snacking. Snacking throughout the day increases the risk of tooth decay. The mouth is acidic for several hours after eating foods high in sugar and starch. Avoid snacking unless you can rinse your mouth and brush your teeth afterward.
• Chew sugar-free gum between meals. Chewing gum increases saliva production by 10 times the normal flow. Saliva strengthens teeth with important minerals. 
• Drink more water during the day if you have low saliva or dry mouth.
• Use fluoride toothpaste. 
• Ask your dentist about measures to restore and prevent enamel erosion and tooth decay.

7/ How is tooth enamel loss treated?

Treatment of yeast loss depends on the individual case. Restoratives (fillings, crowns) help protect teeth, prevent enamel loss from progressing and improve aesthetics. If enamel loss is significant, your dentist may recommend covering the tooth with a crown or veneer. Crowns can also protect teeth from cavities.

Enamel is an important component of tooth structure. The protection of yeast is absolutely essential. To keep enamel healthy, we need to maintain a good diet and oral hygiene by: Brushing teeth twice a day, regularly visiting the dentist every 6 months, limiting foods high in sugar,. .

>> Gums are the lining of the mouth, directly related to the teeth. It covers the alveolar bone and surrounds the neck of the tooth. Gums perform many important functions: adhesion, stability, bonding of teeth, creating a protective layer for bacteria. 

Doctor Truong My Linh