What Is an Alveolar Bone?

Alveolar bone: refers to the lower edge of the maxilla and the upper edge of the mandible inlaid with the tooth root. The alveolar processes of the maxilla and mandible are composed of cortical bone, cancellous bone, and inherent alveolar bone.

Western Medicine Name: Alveolar bone
English name: alveolarbone

Other name: Alveolar process
Affiliated Department: Department of Physiology-Stomatology

Alveolar bone overview

Refers to the place where the lower edge of the maxilla and the upper edge of the mandible are inlaid with tooth roots. The alveolar processes of the maxilla and mandible are composed of cortical bone, cancellous bone, and inherent alveolar bone. The inherent alveolar bone is close to the inner wall of the root and periodontal ligament. It is a layer of bone dense with sieve holes, there is an alveolar socket to accommodate the root, and the periodontal ligament fibers are attached. Alveolar bone can be reconstructed due to stress, with new bone deposits on the tension side and bone resorption on the pressure side. Bone cancellous is located between the bone dense and the inherent alveolar bone. Among them there are many small bone marrow cavities that communicate with each other. The trabecular bones are arranged in the direction of the palatal and muscular forces. Bone density is dense bone located on the lip, cheek, and lingual surfaces of the jawbone, which is connected to the outer plate of the jawbone and can be adapted to disperse the force. Alveolar bone is the most volatile part of the whole body's skeletal system, and its changes can reflect the reconstruction process of bone tissue. It grows with the growth and eruption of teeth, and develops well due to obtaining physiological functional stimulation. When a tooth is missing, it loses its normal functional stimulus and can cause disuse atrophy. Excessive stimulation can cause traumatic absorption. Correction of clinical malocclusion is often based on this biological characteristic of alveolar bone, which promotes the dislocation of teeth to the normal position.

Also known as alveolar process, the jawbone process surrounding the root of the tooth. The socket that contains the teeth is called the alveolar socket. The alveolar bone between the two teeth is called the alveolar space, and the inter-root alveolar bone of multiple teeth is called the inter-root space. The structure is basically consistent with other bones, including cortical bone and cancellous bone. The inner wall is called the inherent alveolar bone, such as a porous bone plate, also called a sieve plate. The vascular nerve of the periodontal ligament is connected to the bone marrow through a small hole in the sieve plate. It is the most active part of the bone. It is rebuilt with the development of teeth, the replacement of deciduous teeth, and the movement of permanent teeth.

Alveolar bone anatomy

The structure of alveolar bone is basically the same as that of other bones, including bone dense and bone cancellous. The arrangement of bone trabeculae within bone cancelles has a certain regularity, which is generally consistent with the direction of tooth force. The trabecular bone between the roots of the teeth is generally horizontal, while the trabecular bone at the bottom of the alveolar is vertical, perpendicular to the apex of the teeth. The chemical structure of alveolar bone is similar to that of cementum. Its inorganic matter is mainly hydroxyapatite, and about 90% of organic matter is collagen.

The inherent alveolar bone is the inner wall of the alveolar bone. It is a porous bone plate called a sieve plate. The vascular nerve of the periodontal ligament is connected to the bone marrow through a small hole in the sieve plate. On the X-ray image, the inherent alveolar bone blocks radiation, forming a white line that surrounds the root of the tooth.

Bundle bone and laminar alveolar bone have two structures, bundle bone and laminar bone. Bundle bone is the new bone that has not yet formed the Haval system. It is layered and parallel to the root surface, in which the periodontal ligament is embedded. The main fiber bundle. Lamellar bone is the bone that has the Haval system.

The alveolar bone is the most active part of the bone. It is reconstructed with the development of teeth, the replacement of deciduous teeth, and the movement of permanent teeth. During bone formation, osteoblasts are arranged around the new bone, and there is a layer of osteoid that has not been calcified immediately below the cells. During bone resorption, the surface of the bone has a cannibalized depression, and multinucleated osteoclasts are visible.

Alveolar bone alveolar distraction osteogenesis

The purpose of alveolar traction is to provide alveolar ridges with ideal height and width and healthy soft tissue for the restoration of dentures through the expansion of the amount of alveolar bone and soft tissue; to create a place for implant dentures; to improve the teeth adjacent to the defect area Periodontal environment; create enough alveolar bone for orthodontic tooth movement.

Alveolar bone indications

1. Complex alveolar bone and soft tissue defects with good wound healing.

2. The defect area must have sufficient residual bone mass.

3. The transmitting and supporting bones must have sufficient bone mass to withstand the transmitting and supporting forces.

Alveolar bone surgery methods and principles

Taking alveolar bone traction combined with implant placement as an example, the basic methods and principles are briefly introduced.

1. Before the tooth is lost, the teeth, periodontal, alveolar bone, gums and periosteum remain relatively coordinated and balanced. Each structure depends on other structures to keep its shape and structure healthy.

2. After tooth loss, there are usually more bone defects at the top of the alveolar bone accompanied by soft tissue defects in the corresponding area.

3. Through the implantation of bone fusion dental implants, the defective teeth can be repaired and reconstructed in terms of function, feel and aesthetics. But first, we must restore the ideal alveolar bone volume and shape, as well as the contour and shape of the gums. The purpose of reconstruction is to obtain alveolar bone with ideal morphology and function with normal cortical bone, bone marrow, periosteum and gums.

4. When the alveolar bone is stretched into bone, a bone incision is made away from the alveolar bone lesion. A retractor is an intra-bone implant that fixes the bone mass and controls the direction and speed of the bone mass movement.

5. Under the control of the retractor, the moving alveolar bone gradually moves in the crown direction, and new bone is formed at the distracted part.

6. The distraction osteogenesis process includes controllable movement of the alveolar bone mass and fixation after the movement. Through the bone regeneration process, the moving bone mass is transferred to the position of the original alveolar bone.

7. The traction force in the vertical direction increases the alveolar bone mass while expanding the soft tissue of Li. Periosteum and gums are part of the distraction osteogenesis and are also expanded.

8. The increase in alveolar bone and the expansion of the gums create good conditions for implant implants. After implants are implanted, it will be enclosed between new bone tissue and residual alveolar bone. Usually the part of the original alveolar bone fixation implant is located on top of the new alveolar bone, and below it is the new bone formed after traction.

9. After the traction process is over, the fixing device must be kept for 10-12 weeks. Implant implantation does not have to wait until the ossification area is completely ossified.

10. The vast majority of alveolar ridges after traction are cortical bones, not suitable for implant implantation and maintenance, and generally need to be modified.

11. Distraction osteogenesis has achieved the following three purposes: sufficient alveolar bone mass was obtained. A large number of medullary bone regions were established for future implant implantation. The soft tissues including periosteum and gums have been expanded. However, distraction osteogenesis of the alveolar bone is generally accompanied by other reconstruction measures. In the case where the alveolar callus is too sharp, if no further widening is performed, simply distraction into bone will not produce alveolar bone sufficient to accommodate the implant.

12. Alveolar osteotomy can increase the width of alveolar bone. Due to the large amount of medullary bone formed during traction, the cortical bone on both sides can be easily separated. The cortical bone on top of the alveolar bone can be removed as appropriate.

13. Place the intraosseous implant in the desired position in the alveolar bone.

14. The alveolar bone above the healing cap can be resected or compressed to collapse. After complete osseointegration is formed, alveolar bone contour trimming is feasible.

The main complications and treatment of alveolar bone

1. Fracture of a transmitted bone mass.

2. Support bone fractures.

3. Premature ossification.

4. The size and shape of the newly formed alveolar bone are not ideal.

Alveolar bone matters needing attention

1. After oral and maxillofacial injuries, especially after damage to teeth and alveolar bone, alveolar bone defects and deformities often occur. The remaining alveolar bone is atrophic, and its height and width become smaller, making it difficult to meet the requirements of denture restoration. While the alveolar bone tissue is defective, the soft tissue of the alveolar bone also exhibits atrophy to varying degrees. Moreover, the teeth around the defect alveolar bone, the periodontal tissue, especially the part adjacent to the defect area, often shows atrophy. Distraction osteogenesis provides an ideal choice for the treatment of alveolar bone atrophy and alveolar bone repair for the installation of implant dentures.

2. Like bone defects in other parts of the maxillofacial region, alveolar bone defects are also complex and three-dimensional. The traction process creates bone matrix, increases bone mass, and expands soft tissue, all of which create the conditions for creating the ideal alveolar bone. However, the traction process itself cannot produce alveolar bone that is ideal in terms of size and shape, and often forms a blade-shaped alveolar bone that needs to be removed by plastic surgery.

3. The above is the basic method of alveolar bone distraction and osteogenesis. The specific operation depends on the specific conditions of the alveolar bone defect and the selected distraction device.