Gingival structure: marginal, keratinized and alveolar

Every person wants to be beautiful. Oral health is a sure sign of good looks. Health is determined by the condition of the gums, which require special care and attention.

Gum - this is mucous membranecovering the parts of both jaws around the teeth. It adheres closely to the jaw bones, passes into the soft tissue of the palate and the mandibular pterygoid fold. The gum, covering the teeth, fuses with the periosteum of the alveolar bone surrounding the roots.

Together with the alveolar ridge, periodontium, cement, enamel, dentin, pulp, it constitutes the periodontium. Therefore, the health of the gums is interrelated with the condition of the adjacent tissues and vice versa. Fixation of teeth in the alveolus (recess for the root) - this is the purpose of the gums, alveolar ridge, periodontium.

The histological structure of the gingival tissue

According to histology, the gum does not have a submucosal layer; its structure has two components: a stratified epithelium and a connective tissue base, otherwise it is called its own lamina.

The basis of the basal layer of the epithelium is made up of cylindrical and cubic cells, then a layer of spine-like cells is placed, then - grains of keratohyalin (a protein accumulating in the cells of the granular layer of the epidermis) and finally - superficial stratum corneum layer. Its cells, flat, non-nuclear, subject to the process of keratinization, are regularly exfoliated and regenerated thanks to the basal and spine cells.

The epithelium does not contain blood vessels and nerve endings. Its purpose is to prevent the entry of pathogenic bacteria into the periodontal tissue. This role belongs to glycosaminoglycans (heparin, hyaluronic, chondroitinsulfuric acid).

The stratified epithelium, more precisely, the basement layer, is separated from the connective tissue base by the basement membrane.

Two layers are distinguished in the lamina propria of the mucous membrane:

1. The first, located on top, is called the papillary. This is a loose connective tissue that forms papillae, directed along a radius to the surface and deepening into the epithelium. The gums are endowed with special sensitivity, because blood vessels, the trigeminal nerve, and nerve endings pass through the papillae.
2. A reticular layer is placed deeper, mostly consisting of collagen fibers produced by fibroblasts. Intertwining, they pass into the periosteum. Therefore, the gums are motionless, and the dentition is continuous.

The main adhesive intercellular substance of the connective tissue is the matrix (35%). It is formed by macromolecules of proteoglycans and glycoproteins: fibronectin, which connects protein with matrix cells, and laminin, which connects epithelial cells to the basement membrane. Cellular composition (5%) - fibroblasts, leukocytes, macrophages, lymphocytes, plasma cells. Fibers make up 60 - 65%.

The blood supply to the gums occurs with the help of the gingival branches. These small arteries appear as loop-like ramifications, dense web-like plexuses, and tangle-like formations that permeate connective tissue. Capillaries in the form of loops enter the papillae, penetrate close to the gingival margin, the most sensitive place

Anatomical structure

Anatomically, the gum is divided into alveolar, otherwise attached, and free, including marginal and interdental. These parts are dense, pale pink in color, brown in dark-skinned people.

Free (marginal)

This is the gingival margin located between the teeth, but not attached to them. The marginal gum covers the neck in the place where the periodontium is localized - the fibers of the circular ligament teeth, which together with other fibers create a thick membrane that prevents mechanical damage. The free part of the gums is smooth, its width is from 0.8 mm to 2.5 mm.

It contains stratified epithelium and connective tissue, including collagen, elastic fibers. The epithelium of the upper border becomes horny, in places it is subject to parakeratinization. Thanks to this function, the gum becomes keratinized, that is, resistant to mechanical, thermal, chemical irritants.

Near the tooth, keratinization of the epithelium (keratinization) does not occur. The mucous membrane is held tightly around the teeth by collagen fibers. This density is due to turgor - the pressure inside the tissue, which is created by tonofilaments. Turgor helps to resist the load on the mucous membrane, makes it stretchable, elastic.

There are 5 main types of collagen fibers:

1. Dentogingival. They are woven into the root under the bottom of the gingival sulcus and fan-like pass into the mucous membrane.
2. Alveolar-ingival. They start from the periosteum of the alveolar process and enter their own plate.
3. Circular. The ring covers the tooth.
4. Transseptal. The cement of the adjacent teeth is connected, through the gingival papillae they pass over the interalveolar septum.
5. Periosteal, that is, oblique. Stretch from the periosteum of the alveolar process to the tooth.

Only the connective tissue of the periodontal ligament contains elastic fibers. In addition, the marginal part is endowed with a considerable number of nerve endings.

Interdental gum

Its structure resembles triangles with vertices directed towards the incisal part of the teeth. They form the interdental or gingival papillae. If the teeth are sparse, the papillae lose their usual shape and at the level of the necks pass into the attached gum. The interdental papillae are covered with stratified cubic epithelium, which is not subject to keratinization. The space between the teeth is closed, inaccessible, which is important to consider when determining the causes of periodontal disease.

The area of ​​adhesion to the tooth surface is called the gingival groove, its role is to seal the tooth, to protect the periodontium from infection. This groove separates the loose and attached gums. It fits the neck, parallel to the gingival margin at a distance of 1-1.5 mm.

The groove located between the edge of the free gum and the tooth is called a gum pocket by dentists. In its normal state, its depth is 3 mm. When it deepens, food debris accumulates there - a favorable environment for the growth of microbes.

Gingival papillae, pocket, gum edge are formed when teeth erupt. In the areas where they are removed, the tissue becomes denser, the gingival papillae disappear.

Gingival groove

The free gum and the tooth surface are separated by a narrow gap 0.5-2 mm deep, stretching from the edge to the attachment epithelium. This narrow space is called the periodontal sulcus. Even a slight inflammation or filling of the gap with deposits leads to the development of dental diseases, a violation of the integrity of the teeth. A slit depth exceeding 2 mm is also often the cause of a painful condition.

The gingival groove is lined by the sulcus epithelium adjacent to the enamel cuticle. The site of this attachment is called the gingival attachment, which includes:

• junctional epithelium 0.71 - 1.35 mm wide, located above the enamel-cement junction, which forms the bottom of the gingival groove;
• connective tissue of fibrous attachment with a width of 1 - 1.7 mm, located at the level of the enamel-cement junction.

For the periodontium to be healthy, the width of the gingival attachment must be at least 2 mm.

From the choroid plexus passing under the connective epithelium, a fluid is formed that penetrates to the bottom of the gingival groove. It contains plasma proteins, fibrin, epithelial cells, microorganisms, immunoglobulins. A small amount of such fluid is considered normal, an increase indicates an inflammatory process.

Attached (alveolar)

The surface is uneven, reminiscent of an orange peel. It covers the alveolar process and adjoins the periosteum closely. The attached gum passes into the mucous membrane lining the part of the lower jaw, the transitional fold. On the upper jaw, it merges with the hard palate, on the lower jaw - with the bottom of the oral cavity.

The immobility of the alveolar gum is created by the connective fibers that attach it to the root and periosteum of the alveolar processes. The epithelium becomes horny.

The width varies from 1 to 9 mm: the widest in the upper jaw in the area of ​​the incisors, the narrowest where the premolars are located. In the lower jaw, especially in the incisors, the gum narrows. It expands with age.

Diseases

The painful condition of the gums is caused by various reasons: a traumatic factor, inadequate oral hygiene, infection, the appearance of ulcerative-necrotic, oncological formations.

Dentists distinguish between diseases provoked by pathogenic microflora plaques, injuries, infection (simple virus herpes, yeast fungi), a decrease in the body's resistance to such microbes as fusobacteria, spirochetes.

According to the localization of the inflammatory process, lesions of the gingival papilla, marginal, attached gums are isolated. Common signs of a painful condition of the gums are hyperemia, swelling, bleeding, plaque.

The following diseases are listed below:

1. Inflammation of the gums (gingivitis) happen due to the traumatic effect of an incorrectly selected prosthesis, an inaccurate edge of a filling, a stone. The disease in the absence of appropriate treatment becomes chronic. This causes the formation of gingival polyps. Also, gingivitis is provoked by pathological processes in the body.
2. Periodontitis (marginal periodontitis) - inflammation in the area of ​​the circular ligament, periodontal, bone tissue of the alveolar process - spreads to one and many teeth. Unlike gingivitis also the bone tissue becomes inflamed. The disease develops as follows: first, the gingival margin is pushed back, a pocket is formed, food gets there, the gum tissue becomes inflamed, swells, bleeds, festers. Then the teeth are loosened, displaced and, if left untreated, fall out.
3. The gingival tissue swells, hurts with concomitant diseases: periostitis, osteomyelitis of the jaws.
4. C-vitamin deficiency is the cause of ulcerative gangrenous manifestations, accompanied by redness, even blue discoloration of the gingival margin.
5. Necrotic ulcerative, hyperplastic processes signal diseases of the blood system.
6. Tuberculous lesion manifests itself first in the form of yellowish-gray tubercles, then in the form of painful external ulcerations of irregular outlines with pitted, pitted edges. Outwardly, the picture of the disease resembles periodontal disease.
7. Signs of syphilis on the gums: in the first phase, there is a hard chancre in the area of ​​the frontal incisors, sometimes in the form of a red spot small colors, in the second - a spotted rash in the form of papules, less often roseola, in the third - tubercles, usually in the area of ​​two to four teeth.
8. Neoplasms are most often benign tumors - these are epulis, fibroma. Fibromatosis is observed with multiple proliferation of fibrous connective tissue, covering several teeth.
9. A cancerous ulcer sometimes develops on the gingival surface, which develops from a malignant tumor of the jaw. It differs from ulcers of inflammatory origin in painlessness, lack of epithelialization.

Operations

If the patient does not consult a doctor on time, does not properly monitor the health of the gums, does not follow the recommendations of the dentist, starts the disease, it is necessary to resort to surgical intervention. It is also necessary when problems arise related to the aesthetic appearance of the oral cavity.

1. Exacerbation of periodontal disease often requires gingivectomy - the excision of a part of the tissue in the area of ​​the gingival pocket. Benign lesions are removed with the adjacent tissue, periosteum. Cutting out the muco-periosteal flaps in the form of a trapezoid, an incision is made at the bottom of the gingival pocket; sewing up the wound, if possible, restore the anatomical structure.
2. The operation, the purpose of which is to give an aesthetic appearance, is called gingivoplasty. It is indicated when a patient develops a periodontal pocket - a depression caused by the detachment of the gingival margin, where food accumulates, and microbes multiply accordingly. While cleaning this cavity - curettage –The gingival margin becomes ugly. Surgical intervention helps to restore an attractive appearance.
3. Target vestibuloplasty - to give volume, which is achieved by dissecting and building it up. The need for this operation often arises in old age, when the size of the gums is significantly reduced.
4. Another type of surgery is the excision of the hood, a kind of tubercle formed due to an increase in the gums during teething, usually wisdom. Food accumulates in this tubercle, which causes even more inflammation.

Undesirable consequences are most often caused by a neglect of the condition of the teeth and gums. Complications can be avoided thanks to the prevention of diseases, regular examination of the oral cavity by dentists, who will help to solve the problems associated with gum disease in time.