TREATMENT OF DENTAL CARIES USING MODERN INSTRUMENTS AND FILLING MATERIALS

Early theories of caries development

Scientists of ancient times were interested in why caries occurs, putting forward their own theories. For example, Hippocrates called the cause of the development of caries disease the mixing of bad “juices” of the human body and saw a direct connection between caries and diseases of the gastrointestinal tract and liver.

Scribonius Largus, a physician from Rome, was the author of the theory that dental disease was caused by microscopic worms invisible to the human eye. These worms, according to the Roman doctor, fed on dental tissues, as a result of which carious holes formed in them. As a therapy, he proposed using the steaming seeds of henbane, a poisonous plant from the nightshade family.

The worm theory of tooth decay remained popular for a long time. Initially, it was adhered to by the famous French dentist of the 18th century, Pierre Fauchard, who is considered one of the founders of modern dentistry. But, having examined the teeth under a powerful microscope, he realized that worms did not exist there, which means that the cause of dental caries lies in a different plane. He put forward his own theory, naming two reasons for the development of caries on teeth: diseased blood and lymph, as well as external influences.

Theories of the occurrence of dental caries during antiquity

Dental caries is the most well-known and, despite recent advances in its prevention and treatment in Western Europe and North America, a very common human disease.

The problem of dental caries has been of interest to many researchers and doctors since antiquity. Depending on the state of development of science and medicine, various theories have been proposed, so it is not surprising that quite a few different concepts of caries have been put forward to date.

Thus, even in ancient times (IV century BC), the outstanding Greek physician and philosopher Hippocrates considered the cause of caries to be the “mixing of bad juices” of the body. He associated the occurrence of caries with diseases of the liver, stomach and other internal organs. Around 43 BC e. The Roman physician Scribonius Largus put forward the theory of caries, according to which the cause of its occurrence is very small, invisible to the eye, worms. In his opinion, they eat tooth tissue, resulting in cavities in the teeth. Based on this, as a method of treating caries, he proposed smoking the patient and carious teeth with smoke from henbane seeds. This theory was also popular in the Middle Ages, existing almost until the middle of the 19th century. Its great supporter was Pierre Faucharde, a famous French dentist of the 18th century. However, in a book about the causes of treatment of dental diseases - “Le Chirurgien Dentiste, au Traitede Dentеs” - in 1778, he nevertheless identified two groups of causes of caries: 1) diseased body juices (blood and lymph) or internal diseases; 2) external influences.

Later, the cause of tooth destruction due to caries was considered to be the effect of gastric acids on them, which entered the oral cavity. The first more or less scientific attempt to substantiate the chemical (acid) theory belongs to T. Berdmore (1728), who experimentally demonstrated the dissolution of enamel with inorganic acids (nitric, hydrochloric, sulfuric). Later, other researchers demonstrated the possibility of dissolving enamel also with organic acids. L. Parmlei and E. Parmlei suggested that dental caries occurs due to the action not of those acids that enter the oral cavity with food, but of those that are formed during the decomposition of food debris in the interdental spaces. The further development of medicine and the discovery of the microscope made it possible to put forward a number of new assumptions regarding the occurrence of caries. In 1678, Anton Lewenhoek, the inventor of the microscope, reported at a meeting of the Royal Society in London about his discovery of microorganisms in dental plaque and dentinal tubules during caries. In 1867 Leber and Rotensthein hypothesized that the causative agents of caries are microorganisms like Leptotrix buccalis. They also assumed that these microbes penetrate the dentin of the tooth, softened due to the action of acids. Thus, by the middle of the 19th century, the foundations of the chemical-parasitic theory of caries were laid.

Modern approach to the study of caries theories

Today, all theories of the development of dental caries are usually divided into two large groups:

Having only historical significance;
They form the basis for scientifically based therapeutic and preventive measures.

The first group includes Entin’s neurotrophic and physicochemical theory of caries, Lukomsky’s trophic theory, Sharpenak’s metabolic theory and a number of others.

Miller's chemical-parasitic theory of caries was of utmost importance in the development of modern dentistry. Today, the main approaches to the prevention and treatment of teeth are based on Miller’s postulates. Let's take a closer look at the most famous theories of dental caries.

Martin and Schatz theory

According to the authors' conclusions, tooth enamel and dentin consist of mineral and protein components. Initial caries occurs as a result of the destructive action of bacterial enzymes on the protein part of tooth enamel. Further development of carious lesions is accompanied by demineralization of the enamel, which is affected by acid compounds with calcium ions. Since they easily dissolve in water, these compounds are washed out of the tooth enamel, and defects appear on it.

Charpenak's theory

An original study on the causes of dental caries was published in the 40s of the 20th century by Charpenak. In his work, he spoke about the existence of a chemical connection between the human body and the hard tissues of teeth. Therefore, the general condition of the body and how the external environment influences it are directly reflected in the teeth.

According to his theory, at the first stage, carious lesion is a dystrophic process that develops without the participation of bacteria. Its cause is metabolic disorders. And only in the second phase of the development of the disease, microorganisms penetrate into the dental tissues and continue to destroy enamel and dentin.

Trophic (biological) theory of caries according to I. G. Lukomsky

I. G. Lukomsky (1948) based his theory on the principle of recognizing the physiological connection between tooth enamel and the body, which, in his opinion, is realized through odontoblasts. He considered odontoblasts as local and directly acting trophic centers of hard dental tissues - dentin and enamel. Violation of their trophic function is reflected in the metabolism in the hard tissues of teeth, the metabolism in them and leads to the occurrence of caries.

The development of caries occurs as follows. External (exogenous) factors affect the body and disrupt metabolism, especially protein and mineral metabolism. Such factors may be a deficiency of vitamins, minerals (especially fluorine), ultraviolet radiation, etc. The action of external etiological factors leads to endogenous changes, in particular in the central nervous system, which disrupt the trophism of enamel and dentin.

As a result of the action of these factors, odontoblasts become defective (dysfunction). Their function is first weakened (asthenized), and then loses its usefulness (moronic). Functional disorders subsequently lead to physiological transformations: the size and number of odontoblasts decrease, their nuclei and tinctorial properties of cells change. All this leads to metabolic disorders in dentin and enamel. First, dismineralization (discalcification) occurs, and then quantitative changes in the composition of hard dental tissues. Along with decalcification, the composition of the organic protein components of these tissues changes. As a result, destructive phenomena occur in the hard tissues of teeth - the carious process itself (Fig. 46).

The theory of the trophic influence of odontoblasts on tooth enamel was confirmed by I. G. Lukomsky in an experiment. In dogs, the odontoblast layer of the tooth buds and the central fibers of the trigeminal nerve were damaged. As a result, foci of destruction, reminiscent of caries, appeared in the animals’ teeth. Based on this, I.G. Lukomsky concluded that odontoblasts, in addition to dentinogenic, also have a trophic function for the hard tissues of teeth (dentin and enamel). However, from the point of view of the trophic theory, it is difficult to explain the role of microflora and a number of local damaging factors in the occurrence of caries, the mechanism of action of some effective treatments for caries, for example, fluoride compounds. Despite this, an undoubted contribution to the theory of caries is the data of I. G. Lukomsky on the relationship between the pulp and hard tissues of teeth and their influence on the development of dental caries.

Entin's physicochemical theory

Having studied the physicochemical properties of teeth and saliva, Entin decided that dental tissue is a partially permeable membrane that separates two environments - blood and saliva. When the normal pressure of these media on the septum is disrupted (due to an unbalanced diet, a weakened state of the body), problems arise with the nutrition of the enamel. As a result, tooth enamel is attacked by pathogenic microorganisms, contributing to the development of caries.

Rybakov's concept

This scientist believed that the cause of dental disease was changes in the pulp - the loose connective tissue that fills the dental cavity. He assumed that the development of carious lesions begins from the inside and spreads from the center to the enamel of the tooth. According to Rybakov’s theory, at different periods of life a person is influenced by various factors that can cause carious tooth decay. In total, the author identified 6 age periods, and in each there were several factors contributing to the development of caries.

The above theories have a rational grain, but at the same time there are many controversial issues that do not fully explain all the nuances of the occurrence of caries. Therefore, it is impossible to create an effective system for the treatment and prevention of dental diseases based on one of them.

Parasitic theory

Even before our era, it was believed that toothache was caused by parasites, but in ancient times people believed that it was worms that destroyed them from the inside. There are many ancient and medieval treatises and journals that described “tooth worms” in detail and also suggested methods of treating them. The most popular of them are the use of henbane seed smoke, pig gastric juice, and concentrated acids.

However, in the 18th century, Leeuwenhoek was able to examine “the smallest animals” in the tissues of a dead (“rotted”) tooth under a microscope. Although scientists were unable to explain how parasites destroy teeth, this discovery became a prerequisite for the emergence of the chemical-infectious theory.

Miller's theory

Miller's chemical-parasitic theory succeeded in becoming the basis for the modern concept of caries treatment. The development of caries, according to Miller, is due to the complex influence of acids and microbes on teeth and occurs in two stages. First, microorganisms ferment carbohydrates, resulting in the formation of organic acids. Under their influence, hard tissues are destroyed and lose minerals. At the second stage, microbial damage to dentin occurs, and the tooth is destroyed even deeper. Along with the local damaging effect of microorganisms, in his work Miller took into account the important role of other factors in the development of caries. Among them are dietary features with a high content of carbohydrates, a lack of minerals, the quality and quantity of saliva, heredity, and social environment.

Although Miller's theory had, along with strengths, weaknesses, and caused a lot of discussion and controversy, it marked the beginning of a whole series of experimental and clinical studies. And many postulates of the modern concept are directly related to Miller’s theory.

Modern scientific theory of caries

Modern scientists (for example, E.V. Borovsky) believe that dental caries occurs due to the negative impact of several groups of factors:

general (poor quality nutrition, water with low fluoride content, diseases and functional disorders of internal organs);
local (microflora, deposits on the surface of the teeth, disturbed composition of saliva, residues of carbohydrate foods in the mouth);
violations of the stability of dental tissues (incorrect chemical composition, hereditary predisposition to caries).

The interaction of different groups of factors creates a situation of increased risk of caries development.

Risk factors for dental caries

Caries occurs when, as a result of negative factors, the integrity of the tooth tissue is disrupted, after which it becomes susceptible to the action of acids in the oral cavity. Factors influencing the emergence of this process are divided into local and general.

Local factors include: