What effect does oral bacteria have on human health?

We brush our teeth every day, especially after getting up in the morning. Of course, some people brush their teeth in the morning and evening. Why do you brush your teeth? First of all, there are some food residues in your teeth, and the other is that bacteria can breed in your mouth, so you should brush your teeth and wash your teeth frequently. So, what effect will oral bacteria have on our bodies?

1, increasing the risk of stroke.

In a study of hospitalized patients with acute stroke, researchers have a deeper understanding of the relationship between specific types of stroke and oral bacteria. Researchers from Osaka, Japan and the University of Louisville, USA * * * conducted this research, and the related results were published in scientificreports, a periodical of Nature Publishing Group.

In this study, the researchers found that the saliva of 26% patients with cerebral hemorrhage contains a special type of bacteria-CNM-positive Streptococcus mutans. In other types of stroke patients, only 6% patients can detect the existence of this bacteria.

Stroke mainly includes ischemic stroke (caused by cerebral vascular occlusion) and hemorrhagic stroke (caused by cerebral vascular rupture).

The researchers also analyzed patients who showed cerebral microbleeds as a result of MRI. These patients may develop dementia and have the possibility of cerebral hemorrhage. It is found that patients with CNM-positive Streptococcus mutans in saliva have more cerebral microbleeds than patients without this bacteria.

2. Increase the risk of esophageal cancer

Researchers at the School of Dentistry of the University of Louisville recently found that there is a bacterium named Porphyromonas gingivalis in 665,438+0% patients with esophageal squamous cell carcinoma (ESCC), which is related to the occurrence of gum diseases. In contrast, this bacterium only exists in the tissues around 12% cancer cells, but it is not detected in normal esophageal tissues. Related research results were published in the international academic journal Infectious Diseases and Cancer.

Wang Huizhi, a scientist in China who led the research, said: "This study shows for the first time that Porphyromonas gingivalis infection may be a new risk factor for ESCC, and this bacterium may also become a new biomarker for the diagnosis of this cancer. If these data are further confirmed, it will show that eliminating a common oral pathogen may help reduce the number of patients with ESCC. "

It is understood that there are two main types of esophageal cancer: adenocarcinoma and squamous cell carcinoma. Squamous cell carcinoma is more common in developing countries.

3, can cause intestinal cancer.

There are thousands of bacteria in the mouth, which is also the reason why diseases enter the mouth. However, according to the research of Harvard Medical School, a kind of Fusobacterium in the oral cavity can even cause intestinal cancer. In the past, scientists only knew that this bacterium was related to intestinal cancer, but this time, researchers at Harvard University found a large number of Fusobacterium in colorectal adenoma. Although colorectal adenoma is a benign tumor, it may also become malignant. The researchers analyzed that this may be due to the immune system overreaction caused by Fusobacterium.

Another study in case western reserve university found that FadA, an adhesion factor on the surface of Fusobacterium, can enter intestinal tumors and cause tumor proliferation. When the molecules are blocked, the development of the tumor is controlled to some extent.

These two studies reveal the new mechanism of colorectal cancer, and also provide reference for future drug research and development.

4. Protect tumor cells

Patients with colon cancer have an unusually large number of common oral bacteria, but the potential role of these bacteria in tumor development is still unclear. A recent study published in the Journal of Immunology by CellPress shows that oral pathogenic bacteria-Fusobacterium nucleatum can protect a variety of tumor cells from being killed by immune cells. This discovery may open a new way for the treatment of cancer patients.

Some bacteria have been proved to be anti-cancer before, so the findings of this paper are surprising. Natural killer cells (NK cells) can protect the body from various health threats, including viruses and parasites. These cells can also kill tumors, but tumor cells have evolved to avoid this immune response. In the early1890s, a doctor named William Collet once said that some bacteria can enhance anti-tumor immunity, and he even successfully treated cancer patients with bacterial extracts. However, the relationship between bacteria and tumors is very complicated. Until now, it is not known whether other types of bacteria have the opposite effect in common cancers: protecting developed tumors from immune cells.

In order to solve this problem, Mandelboim researchers cooperated with Hadassah College of Hebrew University to study whether the anti-tumor activity of natural killer cells is affected by Clostridium nucleatum, an oral pathogen related to periodontal disease, which also exists in human colon tumors.

5. New bacteria for preventing dental caries

Keeping your mouth clean is not just "brushing your teeth with an antibacterial toothbrush, and then removing harmful bacteria, leaving behind bacteria that are beneficial to our mouth".

However, what if there is a milder way to limit the proliferation level of bacteria? American scientists have identified a new type of oral bacteria, which can limit harmful bacteria to a controllable range. This bacterium is called "A 12" and is essentially a streptococcus. One day, this oral cleaning method can be achieved by oral administration, as simple as swallowing a small piece.

In order to prevent the formation of dental caries and maintain dental health. The PH value of the whole oral cavity needs to be maintained in a stable range. If the PH value of the mouth is acidic, there will be many harmful bacteria, which is not good for your small white teeth.

"When this happens, harmful bacteria will continue to produce acidic substances around the teeth and slowly dissolve the teeth. Simple chemical reaction, "said RobertBurne, an oral biologist at the University of Florida." Therefore, we are curious about which bacteria can improve the PH value of the oral cavity. " .

6, will cause serious heart disease.

Recently, researchers from the University of Zurich, Switzerland, found a common bacteria in the oral cavity, which may cause serious diseases if it enters the blood. This research result was published in the recent international journal International Journal of Medical Systematics and Evolution. The new findings will help scientists to study how the bacteria cause diseases and assess the risks of the bacteria.

The bacterium discovered by the researchers was named S.tigurinus (a kind of streptococcus). Streptococcus tigris was isolated from the blood of patients with endocarditis, meningitis and spinal arthritis. It is highly similar to other Streptococcus bacteria and can reproduce in the oral cavity. Common gum bleeding will provide a convenient way for this bacteria to enter the blood, causing serious infection. Dr AndreaZbinden, a researcher who led the study, said: "The identification of Streptococcus tigris is very important for clinical treatment. Accurate identification and study of bacteria is very necessary for tracking the distribution, infection mechanism and transmission route of bacteria, which can provide some clues for us to find suitable therapeutic drugs in clinic.

7. It can be used to diagnose pancreatic cancer.

According to the American Society of Microbiology, there are obvious differences in oral microbial composition patterns between patients with pancreatic cancer and healthy controls. This discovery will be of great help to the early diagnosis of pancreatic cancer. Pancreatic cancer is the fourth most fatal cancer, which seriously threatens human health. Accurate early diagnosis of pancreatic cancer will greatly improve the survival rate of patients, but unfortunately, no effective early diagnosis technology has been developed yet.

In this latest study, the research group I * * * collected samples from 13 1 patients, including 63 females and 68 males. 13 1 people, pancreatic cancer 14 people, pancreatic diseases 13 people, 22 other types of cancer, and healthy 10 people. The results showed that the composition of another oral microorganism (Leptospira and Campylobacter) in patients with pancreatic cancer was significantly higher than that in other groups. At the same time, the composition of the other three oral microorganisms (Streptococcus, Treponema pallidum and Veronella) was significantly lower than that of other groups.

8. Precautions for brushing your teeth

Brush your teeth with cold water

Cold water can cause toothache in people with sensitive dentin, and it is also not conducive to the active substances in toothpaste. The main ingredients in toothpaste are abrasives and fluoride. Laboratory research shows that the optimum temperature for these effective components to work is about 37℃.

Suggestion:

It is best to brush your teeth with warm water close to your body temperature.

Expert comments:

It is best to brush your teeth with warm water.

It is right to brush your teeth with warm water. Some people brush their teeth with cold water, which can cause dentin hypersensitivity and pain. Especially in winter, you need to brush your teeth with warm water to avoid dentin allergy. The temperature of warm water should be close to body temperature. Too hot water is not good.

(2) Brush your teeth too hard

The post said that brushing your teeth too hard may hurt your teeth.

Suggestion:

The strength of 200 grams is enough, which is probably equivalent to picking up an popsicle with your fingers and brushing your teeth with the strength of your wrist instead of your arm.

Expert comments:

The intensity of brushing varies from person to person.

It is also correct not to brush your teeth too hard. It is not that the greater the intensity, the more you can clean your teeth. If you brush your teeth in the wrong way, the greater the intensity, the easier it is to hurt your teeth. But the intensity of brushing varies from person to person, and there is no quantitative standard. Brush your teeth regardless of weight, it is advisable to brush them clean, and everyone can handle them according to their own situation.

(3) Brush your teeth sideways

According to the post, the survey shows that more than 90% people in China brush their teeth horizontally, which is a kind of physical wear on enamel. On the one hand, transverse brushing can't remove the rubbish between teeth, and at the same time, it may lead to wedge-shaped defect of root, gum damage, dentin sensitivity and other problems.

Suggestion:

The correct way to brush your teeth is to brush vertically between your teeth.

Expert comments:

(4) Transverse brush is easy to wear enamel.

Horizontal brush is really not worth advocating. The dentist's advice is vertical brush. Because brushing your teeth horizontally is actually very difficult to brush your teeth, and it can't achieve the effect of thorough cleaning. The worse effect of transverse brushing is to wear the enamel of teeth, especially those who brush their teeth hard, which is easy to form "wedge wear" after a long time. Wedge-shaped wear is characterized by root wear and atrophy, which makes teeth loose and sensitive. Many people have toothache when they are dry in winter, which is caused by wedge-shaped wear.

Experts emphasize that you should brush your teeth vertically. If wedge-shaped wear has occurred, you can go to the hospital to repair it and fill the worn position with resin to avoid further damage to the teeth.

(5) The brushing time is too short.

As mentioned in the post, many people think that the purpose of brushing teeth is to remove food residue. But in fact, the purpose of brushing teeth is to eliminate dental plaque. Dental plaque is a colorless bacterium attached to the tooth surface and gingival space, which is the chief culprit of dental caries and gingivitis. In China, the average time for people to brush their teeth is 59 seconds, which is not enough to thoroughly clean their mouths.

Suggestion:

Brush your teeth for at least 2 minutes. First, carefully brush vertically from the front teeth, especially in places that are easily overlooked, such as between the teeth and the inside of the teeth.

Expert comments:

Brush your teeth for at least 3 minutes at a time.

Brush your teeth for at least 3 minutes at a time to ensure that the tooth surface of each tooth is carefully brushed. As long as you brush your teeth carefully every time, brush your teeth twice every morning and evening. It is not necessary to brush your teeth after every meal, because it takes more than 12 hours for dental plaque to form and adhere to your teeth. Some people's way to protect their teeth is to brush their teeth frequently, which is actually unnecessary. Brushing your teeth too many times is easy to wear your teeth.

(6) Brush your teeth after getting up

According to the post, 98% of China people get up early to brush their teeth every day, and then have breakfast. In this way, the effective tooth protection ingredients in toothpaste do not have much chance to stay on the teeth, but are eaten in the stomach with breakfast.

Suggestion:

Brush your teeth 20 minutes after meals. Rinsing your mouth with water after getting up, eating breakfast and brushing your teeth 20 minutes after meals are the healthiest, especially after drinking acidic drinks or eating acidic food.

Expert comments:

There is nothing wrong with having breakfast after brushing your teeth.

Brush your teeth in the morning and evening, but it is still inconclusive whether to brush your teeth before breakfast or after breakfast in the morning. At present, there is no medical opinion that it is not appropriate to brush your teeth after getting up in the morning. Now most people in China are used to brushing their teeth before breakfast, which is nothing wrong. As for the effective ingredients of toothpaste will be eaten in the stomach after brushing your teeth, this statement is not true. The function of ordinary toothpaste is cleaning. After brushing your teeth and rinsing your mouth thoroughly, there are actually no so-called "effective ingredients" on your teeth. If I don't brush my teeth before breakfast, I always feel that there is a foreign body in my mouth, which is not clean, and I don't feel at ease when eating breakfast. Brush your teeth and rinse your mouth after breakfast to remove food residue from breakfast.

(7) The toothbrush is too big.

Everyone's teeth are big and small, the toothbrush is too big, it is not flexible enough to perform tasks in the oral cavity, and the toothbrush is too small to complete large-scale oral cleaning work.

Suggestion:

Choose a toothbrush with the right size. The size of the toothbrush head should be equal to the width of two and a half to three teeth.

Expert comments:

(8) Replace the toothbrush every 3 months.

It is not recommended to use an oversized toothbrush, and the size of the toothbrush is appropriate to ensure that the brush head can flexibly extend to the rearmost teeth. If the toothbrush is too big, you can't clean the teeth without reaching the last part.

How to grasp the size of toothbrush? It is not accurate to say that the brush head is equal to the width of two and a half to three teeth, because what kind of teeth do teeth refer to? The size of front teeth and big teeth is very different. When you choose a toothbrush, it depends on whether the brush head can flexibly extend into the big teeth for cleaning.

Ordinary toothbrushes can be replaced once every three months, but toothbrushes with deformed bristles should be replaced immediately.