Teeth are an integral part of the body, which helps to chew food to saturate it with the necessary energy. One of the elements of their structure is the pulp. Its features, functions, meaning and structure are described below.
Definition
Pulp is a connective tissue with a fibrous and loose base. It originates from the dental papilla formed by the ectomesenchyme. Such tissue is located in the cavity of the tooth and completely repeats its external contours. The arch of the coronal cavity, depending on the age of the patient, can be at different levels in relation to the neck of the tooth.
The pulp contains nerve endings, fibrous structures and vessels. Another feature of the structure of the pulp is that it contains intercellular substances. They just fill the root canals and coronal parts. In the area of the tooth, where the tubercles of the crown appear on the surface, the "horns" of the pulp are located. In a multi-rooted tooth, the line between such zones is clearly visible, but in single-rooted teeth it is smoother.
Functions
The structure of the pulp is quite complex, because it performs many functions.
1. Plastic - odontoblasts take part in the work, they are responsible for the formation of the pulp layer and are engaged in the formation of dentin. It makes sense to talk about the primary production of dentin, even before teething, and then the secondary is born, which histologically has similarities with the primary. As such a substance appears, a decrease in the cavity of the tooth can be observed.
2. Due to the structure of the pulp, a protective function is performed, for which microphages are created that take part in:
- activation of immune processes;
- dead cells removal;
- formation of lymphocytes and their varieties;
- the appearance of fibroblasts responsible for the production and maintenance of the required amount of the optimal composition of the intercellular substance, due to this, metabolic processes occur;
- development of tertiary dentin, which also performs a protective function.
3. Trophic - it is carried out thanks to a well-developed vascular system, which has some specific features:
- in the pulp, all processes occur at a higher speed compared to other tissues;
- very thin-bodied vessels are observed;
- in the structure of the pulp of the tooth there is such a feature that the pressure there is much higher than in other organs;
- in the intermediate layer there is a huge number of capillaries that are quickly activated at the time of inflammation;
- due to the presence of the anastomosis, there is the possibility of direct shunting of the blood flow.
4. Sensory - the presence of thisfunction is characterized by the work of many nerve fibers that are in the dental cavity due to the existing apical foramen and fan-shaped tissues diverging in the peripheral direction in the area of the crown.
Anatomical structure
If we consider the structure of the tooth from the side of anatomy, then the tissue is divided into two zones.
- Crown pulp is rather friable flesh involved in dentogenesis. All layers that make up the pulp are permeated with a huge number of nerve cells and capillaries.
- The root pulp is denser, since it does not contain such a large number of cellular elements, but there are collagen fibers.
Due to the structure of the crown and root pulp, a sufficiently strong tooth structure is formed. Hard tissue retains the pulp, which in turn is responsible for the formation of dentin.
Through the apical foramen, the canals are connected to periodontal tissues, thereby helping nutrients and minerals to flow to the tooth walls.
The pulp of the front tooth is smoothly redirected from the crown to the root. The dental pulp of molars has more distinct boundaries.
Histological structure of the pulp
- Fibers of collagen and elastin provide the body with hyaluronic acid, reduce susceptibility to bacteria and toxins.
- Fibroplasts, lymphocytes and leukocytes contribute to the life of the epithelium and form a connection between them.
- Stellate cells and single blasts are responsible forpulp regeneration.
- Capillaries and vessels provide the blood supply to the pulp necessary for tissue nutrition.
- A huge network of nerve endings contributes to the formation of Rozhkov's plexuses and is responsible for pain when exposed to stimuli. The innervation of the tissue occurs due to the presence of the trigeminal nerve.
Pulp composition
74% of the fabric is water, and the rest is inorganic and organic layers. The cells contain acids, protein compounds, various enzymes and glucose, which helps the epithelium to actively consume and process oxygen.
Vessels
- Arterioles and arteries - they are redirected from the apical part of the pulp to the coronal, where they branch into a huge number of capillaries. They are in close contact with odontoblasts, thereby providing them with the required nutrients.
- If we consider the structure of the pulp, then there are also veins - due to their presence, the excretion of waste products of the body occurs.
- Lymphatic vessels - produce blind sacs near odontoblasts in which metabolism takes place.
- Apical foramen - formally it cannot be called a part of the vessels of the pulp, but it is through it that the entrance and exit of the lymphatic vessels, arteries and veins from the pulp tissue is formed.
Nerves
The structure of the pulp is such that the dental nerves pass through the apical foramen along with the vessels. They are redirected to the coronal part and form a huge network. Nearodontoblast nerves create the so-called Rozhkov plexus, from which they are redirected without a myelin sheath, which makes it possible to innervate odontoblasts. Together with the peripheral processes, the nerves pass into the dentinal tubules, dentin and predentin.
Pulp of temporary teeth
- Differences in the structure of the pulp of the coronal and root zones are slightly expressed.
- In general, connective tissue is looser and more hydrophilic with reduced fiber content and a more diverse number of cellular elements.
- The most significant number of nerves and blood vessels is observed in children aged 2–3.5 years. The structure of the pulp in children 4–6 years old changes significantly. The number of ratios between collagen and precollagen substrate grows in favor of the former, along with this, an increase in the amorphous intercellular substance is formed.
- Perfectly defined neurovascular bundle.
- The pulp of temporary teeth is tightly connected to the periodontium through the holes of the root of the tooth.
- The structural features of the pulp of temporary teeth is that the nerve fibers are directed to the zone of odontoblasts, where the nerve endings end.
- When the pulp grows, the nervous tissue develops last, and at the moment of resorption of the temporary tooth, it degenerates first, therefore, when the roots are resorbed, the sensitivity decreases significantly.
- When temporary teeth are resorbed, their pulps serve as a source for the formation of clasts - huge multinucleated cells, which, in turn, resembleosteoclasts. Subsequently, dentin and predentin are resorbed, starting from the root.
- Insignificant cavities appear in the periodic layer - vacuoles, they contain a homogeneous mass.
Changes with age
Due to the constant formation of physiological secondary dentin, this eventually leads to a decrease in the volume of the root canal and the pulp chamber. The main features of the structure of the pulp of permanent teeth are the following processes:
- Thinned odontoblast layer or its complete absence. There is also the presence of tissue fibrosis with a reduction in the number of cellular elements.
- There are atherosclerotic changes in the vessels of the pulp. There is calcification of capillaries and nerve endings.
- Pulp tissue becomes more mineralized with age, often manifesting as diffuse calcification.
- The older the patient, the more tissue capacity decreases. All this guarantees people in this category not a very favorable prognosis when using direct coverage or vital amputation.
Inflammation
The structure of the pulp is that when pathogenic bacteria invade through the enamel, they begin to adversely affect the tooth, moving to the soft tissues. When the process of destruction reaches the nerves, a pathogenic inflammation is formed - pulpitis. This pathology occurs in 20 out of 100% of patients who require medical attention for acute pain.
The main cause of pathology is the infectious component of the disease. Nevertheless, mechanical damage to the enamel, as well as poor-quality tooth treatment, can become the impetus for pulpitis.
If we talk about the most characteristic signs of pulpitis, then it is first necessary to note cutting and acute pain, very often paroxysmal. As time passes, the intervals may decrease, and soon the pain becomes constant. In any position, even lying down, there is no respite from discomfort, which can intensify for periods, most often at night, preventing the patient from falling asleep.
At the time of diagnosis, unfortunately, with the help of X-rays, there is no way to detect the disease. Therefore, the main method of recognizing the disease is a routine examination conducted by a specialist. Pulpitis also has certain signs by which a doctor can diagnose the presence of inflammation. For example, when biting in the tooth, there is practically no reaction, but the cold provokes more acute and unbearable feelings.
The only treatment is to remove the pulp. It is performed exclusively under full anesthesia, often in several steps. At the first stage, a drug is placed in the tooth that helps to restore the inflamed tissue, as well as an anesthetic. At the second stage, the tooth cavity is thoroughly cleaned and then sealed. All of the above activities are best done on time, since the pain that accompanies this ailment is simply unbearable.
Disorders of the pulp
All pulpitis most often occur in an acute form. A chronic course is also found, but its signs are not so pronounced as in the case of an acute manifestation, and are most often characterized by a perception of thermal effects - hot and cold food. Quite often he has bad breath. In case of exacerbation, paroxysmal pain occurs. Basically, pulpitis is divided into:
- gangrenous - there is pressure in the tooth when in contact with hot food, when the tooth cavity is opened, you can observe the discharge of gray matter with a pungent odor;
- proliferative - pain occurs at the time of contact with food, which begins to penetrate into the open cavity of the tooth, all this can cause pulpal bleeding;
- fibrous - pain is manifested by mechanical, thermal and chemical stimuli.
All concrematous inflammatory processes, depending on the structure of the dental pulp, are characterized by sudden attacks that are caused by:
- sharp movements;
- vibrations;
- taking the elevator.
