How Caries Took Over the World

If you have been diagnosed with caries, you join the ranks of 99% of the inhabitants of our planet with such a problem. Interestingly, this dental disease is now more common in Europe than in the Middle Ages. It is hard to imagine, but several centuries ago, when dentistry was almost unknown, and few people cared about oral hygiene, three times fewer people suffered from caries. The main reason for such a wide spread of the disease is hidden in our diet and daily habits.

People themselves created the conditions for the emergence of caries, an infection that destroys teeth and is difficult to treat. It is hard to imagine, but once upon a time people did not even know about this problem. Scientists assume that the bacterium Streptococcus mutans, which causes caries, entered the oral cavity from the stomach only 10-15 thousand years ago.

The situation changed when our ancestors switched from hunting to farming. Their diet gradually began to be dominated by carbohydrates - grains, fruits, vegetables and dairy products - instead of animal proteins from meat. For centuries, scientists puzzled over the causes of the tooth decay epidemic. And only half a century ago was the answer found.

Bacteria that cause caries were discovered at the beginning of the 20th century. Later it turned out that not only Streptococcus mutans is responsible for tooth decay. It is actively assisted by several types of streptococci and lactobacilli, which intensify the process. In addition, there are actinomycetes - microorganisms that provoke tooth root caries.

Streptococci have lived in the digestive system of humans and some mammals for centuries without causing harm. To live, these bacteria need carbohydrates, which they get from food, quickly breaking it down. As a result of their activity, alcohols, aldehydes or acids remain. It is these waste products that begin to destroy teeth if the oral cavity is not properly cared for.

When people's diets changed and refined sugar, lemonades and other products with high sucrose content entered them, it became much easier for bacteria to obtain carbohydrates. All these products are ideal for rapid fermentation of carbohydrates. And besides, they are maximally accessible to modern man.

Therefore, we can confidently say that the development of caries is directly related to industrialization and other social processes. They make our lives easier, and also make it easier for streptococci to exist. With the advent of modern products, dental plaque has become an ideal environment for bacteria to live.

To understand how caries affects our teeth, we need to delve a little deeper into chemistry. Dental enamel is 95% calcium hydroxyapatite, a substance with the formula Ca10(PO4)6(OH)2. The crystals of this mineral are hexagonal and form prisms. These structures provide the strength of teeth. A single incisor can contain more than 5 million of these prisms.

Calcium hydroxyapatite gives teeth strength, but it is also one of the main causes of caries. It is a hydroxyl, i.e. alkaline mineral, which is destroyed when in contact with acids. This happens mainly due to a violation of the acid-base balance, which everyone knows about thanks to the annoying advertising of chewing gum.

When acid, for example from wine, gets into the oral cavity, the body begins to fight it. Calcium from the enamel reacts and passes into saliva. But crystalline prisms cannot exist without calcium and the strong structure of calcium hydroxyapatite collapses like a house of cards.

Over time, enamel ceases to be a reliable protection, and acids reach dentin, the soft tissue underneath. As a result, a carious cavity forms in the tooth, which grows and gradually destroys it. The main cause of caries is acids that we get with food. Especially dangerous are “simple” acids: acetic, lactic and citric.

But acids appear in the oral cavity, even if we do not drink wine and avoid citrus fruits. Streptococci of dental plaque feed on carbohydrates that we eat. During fermentation, bacteria release several compounds, including aggressive acids. The simpler the carbohydrate, the easier it is for microorganisms to break it down and release acid.

By actively consuming simple carbohydrates - glucose, fructose, sucrose, we contribute to the development of caries, supplying streptococci with light and nutritious food. It seems that if science knows the cause of caries, it is not difficult to find methods to combat it. But in reality, everything is not as simple as it seems.

At the end of the 19th century, dental scientist Willoughby Miller was the first to seriously study caries. He suggested that dental disease had a chemical-parasitic nature, which was discussed above. Miller found out that caries is a chemical process, but without the help of bacteria, its destructive effect would not be so strong.

Modern science has confirmed Miller's theory. The cause of tooth decay is plaque with bacteria, carbohydrate foods and weak resistance of tooth enamel. It follows that there are only three ways to combat caries: reducing the consumption of simple carbohydrates, strengthening or protecting tooth enamel and eliminating plaque, which is home to streptococci.

Everyone has been told since childhood that teeth are damaged by sweets. But the first to prove the guilt of sweets was only in 1970 by Danish professor Frederik von der Veer from the Royal Dental College in Aarhus. He conducted an experiment with volunteers. The scientist selected people with healthy teeth and asked them to completely stop any oral hygiene.

The participants in the experiment did not brush or rinse their teeth after eating. Half of them additionally rinsed their mouths with a 50% sucrose solution several times a day. Due to the lack of hygiene, the number of bacteria in the oral cavity increased significantly. And the sweet solution provoked the first signs of caries: demineralization of the enamel and the appearance of stains on it.

In the 18th century, sugar and sweets were so expensive that only wealthy people could afford them. Today, most people eat sweets every day. Research has shown that it is not the amount of sugar consumed at a time that is important for dental health, but the frequency of its consumption. In other words, a single box of chocolates once a month is less harmful to your teeth than one chocolate every day.

Today, experts give a lot of scientifically proven advice that helps protect teeth from caries. Dentists advise replacing easily digestible sugars - glucose, sucrose and fructose - with sorbitol, mannitol and xylitol. These sugar substitutes are based on polyhydric alcohols. They are often sweeter than regular sugar, but bacteria practically do not tolerate them.

Not all sugar substitutes are artificial. For example, xylitol is found in popular foods such as strawberries and carrots. Even if it is difficult to give up sweets, you can minimize their harm to your teeth. Doctors recommend eating simple carbohydrates not by themselves, but with other foods. This approach reduces their ability to provoke caries.

Yes, it is not easy to pull yourself together and give up your usual sweets. It is much easier to follow the second rule of protection - to strengthen the enamel of your teeth. This can be done using fluoride. Fluorides were first used to protect teeth more than 70 years ago. In 1953, schools and kindergartens in Switzerland began to fluoridate milk. In the USA, drinking water has been fluoridated for many years.

Today, 95% of toothpastes contain fluoride. Manufacturers add sodium fluoride, monofluorophosphate or aminofluoride. These substances do not cure caries, but help prevent its development. The process looks like this: fluoride ions penetrate the crystal lattice of enamel mineral prisms, significantly reducing their solubility in acids. However, it is important to observe moderation - doctors advise using fluoride-containing pastes in moderation, since excess fluoride can harm the body.

The dream of many generations of doctors is to create a vaccine against caries. It remains unattainable for now, but active research continues in different countries. The greatest progress was demonstrated by scientists from the Institute of Virology in Wuhan. Back in 2011, they published an article about successful tests on rats of a drug based on a combined DNA vaccine. But the development of such a remedy takes time, and research is still ongoing.

It is interesting how a simple change in the diet and lifestyle of our ancestors led to the mass spread of caries, which we are still struggling with. How do you feel about sweets in everyday life? Have you tried to limit their consumption for the sake of dental health - and did you succeed? Share your experience in the comments!