How does saliva pH affect the development of caries?

The main cause of dental caries is the activity of bacteria in the oral cavity. But there are also a number of additional factors that can contribute to the development of this disease. One of these factors is saliva. How the pH of human saliva affects dental health will be discussed in this article.

Why does caries develop?

Scientists are still studying the mechanisms of the development of caries - one of the most common diseases on the planet. They agree that caries is caused by microorganisms living in the oral cavity, in the presence of associated factors. These factors include carbohydrate nutrition, poor oral hygiene, and the qualitative and quantitative composition of saliva.

How does the carious process develop and why do cavities form in teeth? Contrary to popular belief, microbes do not chew holes in teeth; caries develops differently. Cariogenic bacteria (one of the species is Streptococcus mutans) form colonies on the surface of teeth, collecting in a biofilm - dental plaque. These bacteria “love” foods rich in carbohydrates and ferment the sugars contained in them. The products of carbohydrate processing by bacteria are organic acids. So they harm our teeth and contribute to the development of caries.

Acids produced by bacteria disrupt the normal structure of the enamel, promote its demineralization, penetrate into the deep tissues of the tooth and continue to destroy it from the inside. The more microbes in the mouth, the more carbohydrates they receive, the higher the acidity on the surface of the teeth and the more active the process of their destruction occurs.

Ways to normalize acidity

In a pathological state of the body, it is quite difficult to restore the balance of alkali and acid. However, it is quite possible to lower or increase it with the help of proper nutrition and taking medications recommended by the doctor. The following are foods that increase acidity:

salt;
Fish and seafood;
cereals and legumes;
meat;
sugar and its substitutes;
sweet carbonated drinks;
products made from wheat flour;
alcoholic drinks;
tobacco.

However, it should be taken into account that regular consumption of these products negatively affects the body and leads to a decrease in immunity, the occurrence of pancreatitis and gastritis. In women, an increase in acidity negatively affects reproductive function, and in men it provokes infertility and impotence, since sperm die in an acidic environment.

The following products increase the alkaline environment:

parsley;
spinach;
ginger;
garlic;
vegetable juices;
watermelon;
peach;
citrus;
melon;
mango.

Balances acidity with water, nuts, and lettuce. To maintain the normal pH of saliva and other fluids in an individual’s body, it is recommended to drink alkaline mineral water according to the following scheme:

one glass in the morning;
two - during the day.

In addition, it is advisable to use this water for cooking and brewing tea.

What is the role of saliva in maintaining oral health?

Saliva is the biological fluid of our body that is produced by the salivary glands. Constantly present in the oral cavity, saliva takes part in the digestive processes, nourishes tissues, provides natural cleaning of the oral cavity, and protects teeth and mucous membranes from bacterial exposure. All natural processes that occur with our teeth are carried out in interaction with this biofluid. Saliva ensures the normal functioning of all tissues and organs of the oral cavity; in particular, the important role of saliva in maintaining the mineral composition of tooth enamel has been proven.

In addition to water, saliva contains phosphates, calcium salts, fluorides, sodium compounds and other substances that help strengthen and maintain the health of tooth enamel. Essentially, salivary fluid is a solution supersaturated with calcium and phosphate salts. Due to this composition, saliva qualitatively mineralizes teeth. Medical research has proven that during teething, enamel matures primarily due to the active intake of calcium and phosphorus ions from saliva. It also maintains and, if necessary, restores the correct balance of minerals in already erupted teeth.

In addition to its mineralizing function, the protective role of saliva has been proven. It contains lysozyme and some other substances with bactericidal and bacteriostatic effects. Thanks to this, saliva neutralizes the action of pathogenic microorganisms and prevents the development of infections of the teeth and oral cavity. And finally, saliva performs a cleansing function, washing away food debris and germs.

Thus, normal quality and quantity of saliva is the most important condition for healthy teeth and oral cavity. Any violations of its quantitative or qualitative composition can provoke the development of caries, diseases of the mucous membranes and periodontium.

Alkalinization or alkalosis

If a person’s pH of saliva and other biological fluids is higher than permissible values, then alkalosis develops. Fortunately, this condition is extremely rare, and mainly occurs in patients with ulcerative lesions of the digestive tract who are taking certain medications. When food is alkalized, due to slow digestion, it begins to rot and release toxic substances. The pathology manifests itself as weakness, poor appetite, and itching of the dermis. Calcium begins to deposit in the kidney tubules. At later stages, kidney failure develops and the body does not accept dairy products. The individual’s existing chronic diseases worsen, frequent constipation appears, and susceptibility to allergens increases. As a result of such a clinical picture, it is difficult to identify and eliminate the true culprit of alkalosis.

What happens when there is insufficient saliva production?

According to statistics, every fifth adult is diagnosed with xerostomia, or dry mouth. This condition is caused by the fact that a person has reduced or completely absent saliva production. Since this biofluid performs a number of important functions, with xerostomia negative changes occur in the oral cavity:

discomfort occurs;
the level of hygiene of teeth and gums decreases;
Due to a lack of saliva, the pH of the oral cavity decreases, microbes actively multiply in the mouth, and dental caries may begin to develop.

Saliva acidity

Normally, the pH of saliva is in the range of 6.8–7.5. It has been established that the acidity of saliva depends on the rate of salivation and, at high values, can reach a pH of 7.8. To ensure the reliability of the results, measurements are taken on an empty stomach or two hours before or two after a meal. The best time for measurements is from 10 to 12 hours. It should be remembered that saliva production decreases in the evening and at night. With an acidic environment in the mouth, tooth enamel demineralizes, caries forms, and the gums become inflamed.

How does saliva pH affect teeth?

One of the protective elements of saliva is the so-called buffer system. Its task is to neutralize the negative effects of acids entering the oral cavity. Buffer systems maintain a normal pH level in the oral cavity, providing protection against acid-base influences. It is the buffer systems of saliva that influence the restoration of the pH of the oral cavity within minutes after eating.

If the pH of saliva is disturbed, buffer systems do not cope with their task and cannot neutralize acids. This leads to the fact that tooth enamel quickly loses mineral substances, caries develops, as well as non-carious lesions of dental tissues.

Dietary habits and poor oral hygiene can affect changes in the pH level of saliva, and therefore play a role in the development of caries. Some diseases and conditions also affect the process of salivation. For example, with Sjogren's syndrome and diabetes, saliva production decreases, dry mouth and related problems occur. In cases of dysfunction of the thyroid gland, rheumatoid arthritis, and some mental illnesses, saliva does not perform its mineralizing function, that is, it does not provide tooth enamel with a sufficient amount of calcium and phosphorus ions. This explains the fact why, with concomitant diseases, caries in patients is much more common and can develop at a faster pace.

Research also shows that the normal pH level of saliva is different for children and adults. In children, the enamel begins to lose minerals at higher pH levels, and the acid-base balance in the oral cavity is restored more slowly due to the smaller volume of saliva compared to adults. Therefore, caries in childhood develops much faster.

Measurement methods

Litmus paper is a tool that allows you to determine the pH of saliva in the mouth both in the laboratory and at home. Such test strips can change color in the presence of alkalis and acids. The environment, accordingly, can be neutral, alkaline, acidic.

Important! Using litmus strips is very simple - just dip the strip in the desired solution for 2-3 seconds and compare the resulting shade with the scale.

How to use a litmus test strip should be read in the instructions

An acidic environment is considered when Ph is less, alkaline - more than 7. Indicator paper can have different forms, sold in the form of strips, boxes, rolls, pencil cases, tubes. It is noteworthy that universal litmus strips are used exclusively for determining Ph values over a wide range (accuracy - up to 1 unit or tenth).

Prevention of salivary disorders and dental caries

Saliva and tooth decay are closely related, and it is important to have enough saliva in your mouth to protect your teeth. The following preventive measures will help prevent disruption of salivary processes and minimize the risks of dental caries:

Drink enough water and other fluids to keep your body hydrated.
Maintain good oral hygiene: brush your teeth twice a day, thoroughly removing plaque. Pay attention to the interdental spaces, gums and tongue. It is recommended to additionally use irrigators. These devices clean hard-to-reach areas of the oral cavity using a water jet. In this way, you can not only remove contaminants, but also moisturize the mucous membranes in case of increased dryness.

Give up bad habits; smoking and drinking alcohol reduce saliva production, lead to dry mouth, and therefore increase the risk of dental caries.
For xerostomia, on the recommendation of a doctor, you can use special rinsing solutions that increase the hydration of the mucous membranes.
If necessary, the doctor can prescribe drugs that imitate the natural component of saliva.
Sometimes salivation decreases due to taking some medications. In this case, it is recommended (after consultation with a doctor) to discontinue them or limit their use.
It is equally important to normalize nutrition by limiting the amount of carbohydrates and sweet foods, which are a favorable environment for the development of pathogenic microorganisms, greatly disturb the pH of the oral cavity after eating, and are one of the most important factors in the development of caries.
And, of course, to prevent any dental diseases, it is important to visit a doctor twice a year. Along with a traditional dental examination, modern clinics offer salivary pH tests and thesiography. This is a diagnostic method that will help determine the mineralizing potential of saliva.

Ph meter

This device allows you to measure acidity at home. It is believed that it does not have high accuracy, but it is inexpensive and convenient to use. The cost of a Ph meter depends on its characteristics. In particular, you should pay attention to the measurement range - from 0.00 to 14.00. In addition, indicators such as operating temperature, device division value, and accuracy are important. When purchasing, it is worth considering that the device must be calibrated.

What is the sequence of steps to determine the acidity of saliva, urine, blood or other liquids at home using a Ph meter:

it is necessary to remove the protective cap at the bottom of the device body;
turn on the device (move the slider to the right);
immerse the Ph-meter up to the grooved mark in the liquid whose acidity is to be tested (in this case, in mixed saliva);
read the readings after they have stabilized.

After each measurement, it is necessary to thoroughly rinse the electrode of the device with distilled water. As soon as the manipulations are completed, wipe the device dry with a napkin and put on the protective cap.

Important! To obtain reliable data, it is recommended to measure the acidity of saliva at least 5–8 times a day.