Parts of the jaw that hold the teeth are called alveolar. They consist of bone tissue (from its compact and spongy substance). In them are the holes in which the beginnings of the teeth are born. Over time, they grow. Bone tissue also develops around, so that the teeth have additional support. This jaw area is called the alveolar bone .
If we consider the area by segments, then for each tooth, you can select the hole in which it is located, and bone formations around with mucous membranes. Nourishing vessels, nerves and bundles of connective tissue fibers are suitable in the hole.
Alveolus
What is a hole for attaching a tooth? This is a depression in the bone tissue of the jaws, which is formed by birth. The difference in the teeth on the lower and upper jaw is almost not noticeable. More they differ in purpose: incisors, fangs, molars. Different groups perceive an uneven load when chewing food.
In front, the alveolar processes of the jaws are thinner, and on the sides (places for chewing) they are thicker and more powerful. Dental wells differ in shape. They may have partitions located slightly deeper than the side bridges. This division is associated with a different structure of the roots of the teeth. Some of them can be kept on one trunk, and can have two or three of them.
Alveola accurately repeats the size and shape of the tooth. Rather, it grows in it, increases in size, changes the direction of the root canals. The bone tissue of the alveolar processes surrounding each tooth, adjusting to it, grows in the same rhythm. If it does not fit snugly, then very soon the incisors and molars that absorb the greatest load will begin to stagger and fall out.
Alveolar processes
Normally, these areas of bone tissue around the teeth develop in each person in the process of growing up. However, with some genetic disorders, the alveolar process may not grow.
One of such cases is a pathology in which dental primordia do not form at all in the process of embryonic development. Such situations are quite rare. Naturally, the teeth do not grow out. Part of the jawbone does not develop, which under normal conditions would become a platform for the alveolar processes. Actually, the border between these formations under normal development is practically lost. The bones of the jaw and the process are actually fused.
From this we can conclude that the process of their formation is directly related to the presence of teeth. Moreover, with their loss or removal, bone tissue in this place gradually loses its properties. It softens, turning into a gelatinous body, decreases in volume, reaching the edges of the jaw bone.
Features
The alveolar process of the upper jaw consists of an internal (lingual) and external (labial or buccal) wall. Between them is a spongy substance, similar in composition and properties to bone tissue. The bones of the jaws vary. Above they are formed of two fused halves. A jumper of connective tissue runs in the middle.
In terminology, you can also find the concept of "alveolar part". In this case, the process on the lower jaw is implied. Its bone is not paired, it has no connection in the middle. But besides this, the shoots are not much different in structure. At the bottom, lingual, labial and buccal walls are also distinguished.
It can be noted that the alveolar process of the lower jaw is less prone to fractures. On the one hand, this is due to the fact that in most people the upper teeth cover the lower ones and take the traumatic load first. On the other hand, the walls of the anterior processes from above are slightly longer and thinner. In addition, the dense compact substance of the tissue in this place is more penetrated by the pores for conducting vessels and nerve endings. Therefore, it is less dense and durable.
Problems: Diagnostics
Teeth in the process of human life undergo changes. Not only do they become smaller, their mobility also increases. The bone tissue around them is slowly degrading (resorption). The load-bearing part is more susceptible to this. In fractures, it is often not possible to palpate the alveolar processes of the jaws to determine the degree of damage without pain relief. These areas are densely penetrated by a network of nerve endings, and therefore painful.
Such areas, as well as foci of age-related destruction (destruction), sclerotic changes (replacement of bone tissue connective) and manifestations of osteomyelitis are diagnosed by a radiograph in various projections. In some cases (tumors), MRI is prescribed, studies of the maxillary sinuses using a contrast medium. Comprehensively diagnosed are clearly expressed problems of growth and development of the jaws, as well as their processes.
Atrophy
The processes of the jaw are bone formations to support the teeth in the holes. If they fall out, the need for processes disappears. There is nothing more to support, the spongy substance, without feeling the load, is destroyed. With anodontics (genetic pathology of the absence of tooth primordia from birth), the alveolar processes do not develop, although the jaws form.
Atrophic processes occur with individual characteristics. In some, the height decreases faster, in others more slowly. Atrophy of the alveolar process in the upper jaw leads to the formation of an almost flat palate. From below, this leads to a noticeable protrusion of the chin. The jaw closes more and without prosthetics acquire a characteristic "senile" look.
Atrophy can also be caused by inflammatory processes. The greatest danger is periodontitis, osteoporosis, osteomyelitis. Cervical caries also causes tissue dystrophy. May cause atrophy and periodontal disease. Despite the apparent simplicity of this disease, in the absence of response, the trophism of the mucosa and processes is broken, interdental pockets appear, the neck of the tooth is exposed, it begins to loosen and falls out.
Cleft alveolar bone
Such a pathology appears at the stage of embryonic development. At about two months after conception, skull bones form. By birth, they close and fit snugly together. On the surface of the front of the jaw remains only a small depression (dog fossa).
The confluence of various factors (heredity, medication, pesticides, alcoholism, smoking during pregnancy) can cause a situation where the paired bones of the sky do not connect and grow together, a cleft (cleft palate) forms . It can be localized on soft or hard palate, bones of the jaw, spread to the lip (cleft lip). There are full or partial non-growth, lateral or median.
The alveolar process of the upper jaw with a cleft, as a rule, is a continuation of the overgrown bones of the upper palate. Separately, such a pathology is rare. On the lower jaw and its alveolar part, a cleft almost does not occur.
Fracture
A jaw injury often results in a knocked out tooth. Causes can be mechanical injuries, unsuccessful falls, punches or a massive object. If the exposure area is larger than the area of one tooth, a fracture of the alveolar process is possible. The crack often has an arcuate shape.
Allocate a full, partial and fragmentation fracture. By localization, it can affect the roots of the teeth, fall on their necks or located above the zone of the alveolar processes - along the jaw bone. The prognosis for natural bone fusion is complex and is given depending on the severity of the condition and localization. Debris with damage in the root area most often does not take root.
In addition to pain and swelling of the affected area, its symptoms may include: malocclusion, speech distortion, difficulty in chewing. If there is an open wound and the blood has a foamy structure, crushing of the walls of the maxillary sinuses is also assumed.
Alveolar bone grafting
Correction of conditions for jaw pathologies of a congenital nature, plastic surgery for fractures and bone growth for prosthetics are divided. The absence of a tooth over a long period leads to atrophy of the bone tissue of the site. Its thickness may not be enough when installing reinforcement for mounting an insert tooth. When drilling, perforation into the maxillary sinus region is possible. To prevent this, they perform plastic surgery. The alveolar process can be increased by laying on the surface of the jaw bone, or use its dissection and filling with biomaterial.
Fragmentation of fragments during fractures is usually carried out using splinted teeth and wire staples. Fixation through the through holes in the bone using kapron ligature can be applied. Contour plastic repair of defects in embryonic development consists in closing the opening by moving adjacent tissues to the required position and using implants. The operation should be carried out as early as possible so that the child has time to develop the speech apparatus.