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Tooth decay

life science Maturity 7-9

Tiny bugs live in your mouth.

ToothMontage3.jpg
ToothMontage3.jpg
They eat the sugar in your food. This makes a sour liquid. The liquid can make holes in teeth. These holes can hurt.
Toothbrush 20050716 004.jpg
Toothbrush 20050716 004.jpg
You can brush to keep teeth clean. Do you brush your teeth every day?

47 words

Tiny bugs live in your mouth.

Streptococcus mutans 01.jpg
Streptococcus mutans 01.jpg
They love to eat sugar from your food. When they eat, they make a sour liquid. This liquid can melt the hard parts of your teeth.
Blausen 0864 ToothDecay.svg
Blausen 0864 ToothDecay.svg
This can make small holes called cavities. Cavities can be white, brown, or even black. They can make your teeth hurt when you eat.
Toothbrush 20050716 004.jpg
Toothbrush 20050716 004.jpg
You can brush your teeth twice every day. Using floss also helps keep them clean. This helps keep your smile bright and healthy!

88 words

Tooth decay is the breakdown of your teeth.

Blausen 0864 ToothDecay.svg
Blausen 0864 ToothDecay.svg

Tiny bugs live in your mouth. We call this sticky mass plaque.

Streptococcus mutans 01.jpg
Streptococcus mutans 01.jpg

Some bacteria, like Streptococcus mutans, love to eat sugar. When they eat sugar, they make acid. This acid can melt the hard parts of your teeth. This melting is called demineralization.

Dental caries etiology diagram.png
Dental caries etiology diagram.png

First, you might see a chalky white spot. This is a tiny hole. Soon, the spot can turn brown or black. This creates a cavity. Cavities can cause pain. They can make it hard to eat. If decay gets deep, it can cause an infection.

You can help keep your teeth strong. Brush your teeth twice every day. Use floss once a day to clean between teeth. Using fluoride can also help. Fluoride is a mineral found in water and toothpaste. It helps fix the hard parts of your teeth.

Toothbrush 20050716 004.jpg
Toothbrush 20050716 004.jpg

Many people around the world have tooth decay. Nearly all adults will have it at some point. Eating less sugar can help prevent it.

178 words

Tooth decay is a common problem where teeth break down. This process is also called caries, which is a Latin word for "rottenness."

Blausen 0864 ToothDecay.svg
Blausen 0864 ToothDecay.svg
When teeth decay, they can change color from yellow to black. This can cause pain or make it hard to eat. If the decay gets very deep, it can cause an infection or an abscess.
Dental infectionMark.png
Dental infectionMark.png
Scientists are currently studying how to use stem cells to regrow teeth. For now, most treatments only help ease the symptoms of decay.

Decay happens through a specific way it works. Tiny living things called bacteria live in your mouth. They form a sticky, creamy mass on your teeth called plaque.

Streptococcus mutans 01.jpg
Streptococcus mutans 01.jpg
Some bacteria, like Streptococcus mutans, love to eat simple sugars. When these bacteria break down sugar, they produce acid. This acid dissolves the hard parts of your teeth, like the enamel and dentin.
Dental caries etiology diagram.png
Dental caries etiology diagram.png
This dissolving is called demineralization. If this happens more than your saliva can fix, a cavity forms.

Understanding how this happens helps us see why it is so common. Bacteria turn sugars like glucose and fructose into lactic acid.

Stephan curve.png
Stephan curve.png
This happens through a process called fermentation. One common sugar is sucrose, which is also called table sugar. Bacteria use sucrose to make a very sticky substance called dextran. This helps the bacteria stick to your teeth even more tightly.
Dental carries anaerobic fermentation.tiff
Dental carries anaerobic fermentation.tiff
This creates a sheltered place for the bacteria to grow and make more acid.

Tooth decay affects many people across the entire world. As of 2016, about 3.6 billion people had decay in their permanent teeth. This is about 48% of the whole human population.

Dental caries world map - DALY - WHO2004.svg
Dental caries world map - DALY - WHO2004.svg
In baby teeth, it affects about 620 million people. The World Health Organization says nearly all adults will have decay at some point. It is often more common in the developed world because people eat more simple sugar. However, people in the developing world may have less access to dental care.

You can protect your teeth by following a few simple steps. Brushing your teeth twice every day is a great start. You should also floss between your teeth once a day.

Toothbrush 20050716 004.jpg
Toothbrush 20050716 004.jpg
Using fluoride can also help your teeth stay strong. Fluoride is a mineral you can find in water, salt, or toothpaste.
FluorideTrays07-05-05.jpg
FluorideTrays07-05-05.jpg
Eating a diet with less sugar also lowers your risk. If a cavity does form, a dentist can use different treatments to fix the tooth.
ToothMontage3.jpg
ToothMontage3.jpg

425 words

Tooth decay, also known as dental caries, is the breakdown of tooth structures. The word "caries" comes from the Latin word for "rottenness."

Blausen 0864 ToothDecay.svg
Blausen 0864 ToothDecay.svg
This condition occurs when acids dissolve the hard tissues of the teeth. These tissues include the enamel, the dentin, and the cementum. Decay can cause many different colors, ranging from yellow to black. Symptoms often include physical pain and difficulty eating. If left untreated, complications can include inflammation of surrounding tissue, tooth loss, or the formation of an abscess.
Dental infectionMark.png
Dental infectionMark.png

The mechanism of decay involves a complex interaction between bacteria, food, and the tooth surface. Bacteria in the mouth form a sticky, creamy mass called plaque. This plaque acts as a biofilm, which is a sheltered environment for microbes.

Dental carries anaerobic fermentation.tiff
Dental carries anaerobic fermentation.tiff
Certain bacteria, such as Streptococcus mutans and Lactobacillus, are highly cariogenic, meaning they cause decay. These bacteria consume fermentable carbohydrates like glucose, fructose, and sucrose. Through a process called fermentation, they convert these sugars into acids, primarily lactic acid.
Streptococcus mutans 01.jpg
Streptococcus mutans 01.jpg
These acids cause demineralization, which is the dissolution of the tooth's mineral content. If the rate of mineral loss is greater than the buildup from saliva, a cavity forms.

Decay progresses through several distinct stages and visual changes. The earliest sign is often a chalky white spot on the enamel. This is called an incipient carious lesion or a "micro-cavity." As demineralization continues, the spot may turn brown and eventually progress into a cavitation, or a physical hole.

Pit-and-Fissure-Caries-GIF.gif
Pit-and-Fissure-Caries-GIF.gif
If a lesion appears dark brown and shiny, it may mean the demineralization has stopped, leaving only a stain. Active decay, however, usually appears lighter in color and looks dull. As the decay moves through the enamel into the dentin, the tooth may become sensitive to heat, cold, or sweets. This happens because the dentinal tubules, which lead to the tooth nerve, become exposed.
Smooth Surface Caries GIF.gif
Smooth Surface Caries GIF.gif

Several factors influence how quickly decay develops. The frequency of acid exposure is a major driver. After eating sugar, the pH level in the mouth drops suddenly.

Stephan curve.png
Stephan curve.png
This drop is shown on the Stephan curve, which tracks how acidity changes after sugar consumption. While saliva helps buffer this acid and return the pH to normal, frequent snacking keeps the teeth in an acidic state. Other risk factors include low saliva production. Conditions like diabetes mellitus or Sjögren syndrome can reduce saliva. Some medications, such as antidepressants or antihistamines, also decrease saliva. Furthermore, receding gums can expose the roots, which are more easily decayed because of the cementum.

Historically and socially, dental caries show significant global patterns. The disease is more common in the developed world due to higher consumption of simple sugars. However, access to professional dental care is often much lower in the developing world. Socioeconomic status also plays a role, as poverty can limit education about dental care and the ability to pay for treatment. Interestingly, dental decay can be passed from a caretaker to a child. This happens through a caretaker's kiss or by feeding a child pre-masticated food, which spreads certain bacteria.

Dental caries world map - DALY - WHO2004.svg
Dental caries world map - DALY - WHO2004.svg

The scale of this issue is massive. As of 2016, approximately 3.6 billion people, or 48% of the global population, had caries in their permanent teeth. In baby teeth, the condition affects about 620 million people, which is 9% of the population. The World Health Organization estimates that nearly all adults will experience dental caries at some point in their lives. Because the disease is becoming more common in both children and adults, prevention is a global priority. Currently, scientists are researching stem cell-based methods to see if tooth regeneration is possible. For now, medical science focuses on easing symptoms and restoring function.

Prevention and treatment are the primary ways to manage the disease. Regular cleaning and a low-sugar diet are essential. Brushing twice a day and flossing once a day are highly recommended.

Toothbrush 20050716 004.jpg
Toothbrush 20050716 004.jpg
Fluoride is a vital tool for prevention. It can be found in water, salt, or toothpaste, and it aids in the remineralization of the tooth.
FluorideTrays07-05-05.jpg
FluorideTrays07-05-05.jpg
If a cavity has already formed, a dentist may use various treatments to restore the tooth. This might include fillings to close the hole.
ToothMontage3.jpg
ToothMontage3.jpg
In very advanced cases where the pulp tissue is overwhelmed or the tooth is too weak, the tooth may need to be removed entirely.

737 words
🖼️ Images & Media (21)
File:ToothMontage3.jpg
ToothMontage3.jpg
File:Dental caries etiology diagram.png
Dental caries etiology diagram.png
File:Streptococcus mutans 01.jpg
Streptococcus mutans 01.jpg
File:Stephan curve.png
Stephan curve.png
File:Blausen 0864 ToothDecay.svg
Blausen 0864 ToothDecay.svg
Dental carries anaerobic fermentation.tiff
File:Pit-and-Fissure-Caries-GIF.gif
Pit-and-Fissure-Caries-GIF.gif
File:Smooth Surface Caries GIF.gif
Smooth Surface Caries GIF.gif
File:Dental explorer.png
Dental explorer.png
File:Dental infectionMark.png
Dental infectionMark.png
File:Lp473524f2 online.jpg
Lp473524f2 online.jpg
File:GV-BLACK.JPG
GV-BLACK.JPG

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