Gingiva:
is tough connective tissue which lines the base of the teeth, holding them in place 
and protecting the jaw and teeth roots from infections. Known informally as the gums, the gingiva are a very important part of the oral anatomy, and caring for them is critical to maintaining oral health. Problems with the gingiva can be identified during routine oral examinations, or noted by patients who experience changes in their mouths.
and protecting the jaw and teeth roots from infections. Known informally as the gums, the gingiva are a very important part of the oral anatomy, and caring for them is critical to maintaining oral health. Problems with the gingiva can be identified during routine oral examinations, or noted by patients who experience changes in their mouths.
connective tissue has a strong fibrous underlayer, covered in a layer of mucous membranes. The gingiva are very tough, designed to resist trauma from chewing and hard foods which enter the mouth. The base of this tissue is firmly anchored to the bone, while the upper portion is free, allowing the gingiva to run between the teeth to help stabilize them and keep them in place. In addition to anchoring the teeth, the gingiva also create a seal which prevents bacteria, plaque, and other foreign material from entering the roots of the teeth, where it could cause trauma or infection.
When a patient's gingiva become chronically inflamed, the condition is known as 
gingivitis. Classic symptoms of gingivitis can include changes in the color of the gingiva, along with swelling and bleeding. Patients may find that their gums are very tender after brushing their teeth, or that the gums bleed freely after oral care or eating. Gingivitis can lead to complications which include serious infections, and it is an issue which needs to be addressed.
gingivitis. Classic symptoms of gingivitis can include changes in the color of the gingiva, along with swelling and bleeding. Patients may find that their gums are very tender after brushing their teeth, or that the gums bleed freely after oral care or eating. Gingivitis can lead to complications which include serious infections, and it is an issue which needs to be addressed.
Over time, the gingiva can recede. Sometimes gum recession is caused by gingivitis, but it can also be associated with other oral problems, or occur on its own. Receding gums are a cause for concern because they can expose a patient to the risk of infections and destabilize the teeth. Other gingival diseases can include gingival cancer, in which the cells in the gums become malignant, and gingival hyperplasia, in which the gums grow grossly enlarged.
The gingiva is that portion of the gums that surrounds the teeth and lies above the level of the bone. The diagram to the right is a detail which shows the microscopic structure of this vital attachment of the gums to the tooth. The soft tissue is covered by an epithelial layer (red) called the oral epithelium. This attaches to the surface of the tooth on the dentin between one and three millimeters below the level of the crest of the gingiva. The part of the gingiva below the crest but above the attachment is called the free gingival margin. The potential space between the free gingival margin and the tooth (collapsed in life) is called the gingival sulcus. Just below the epithelial attachment lies a large number of connective tissue fibers (blue) called the gingivo-dental fibers. Some, which are not visible here actually circle the entire tooth and are called circular fibers. These fibers are responsible for securely attaching the gingiva to the tooth.
In light-skinned individuals the gingiva can be readily distinguished from the adjacent dark red alveolar mucosa by its lighter pink color.
In dark-skinned people the gingiva may contain melanin pigment to a greater extent than the nearby alveolar mucosa. This melanin pigment is synthesized in specialized cells and is produced as granules that are stored within the cells that produce melanin. If pigmented gingiva is surgically inspected it will often heal with little or no pigmentation. Therefore surgical procedures should be designed so as to preserve the pigmented tissues. Clinicians sometime use the terms free and attached gingiva. Attached gingiva refers to the portion of the gingiva towards the top of the tooth. Free gingiva is firmly bound to the underlying tooth and alveolar bone.
The area of the gingiva near the crown of the tooth (Gingival margin) in young people is more likely to become exposed as a result of tooth eruption.
he gingiva occupies the spaces between teeth. It is composed of a pyramidal papilla in the incisor region. The gingiva is attached to the tooth by an epithelium and by connective tissue fibers at the top.
The attachment (between the gingiva and the teeth) is responsible for separating the dirty oral environment from the totally clean environment inside the body. The gingival attachment is doubly important because it protects the underlying bone (alveolar crest) from becoming infected. Nature is especially protective of the bone because it is not highly vascularized and an infection in bone, especially in pre modern man's environment would have been a death-dealing event. An infection in bone is called osteomyelitis, and even today, with modern antibiotics, it is still quite a dangerous condition. Thus nature built in a simple mechanism to protect mammals from getting osteomyelitis as they aged and became more susceptible to oral infection. She programmed the bone to reabsorb (to be absorbed); to "get out of the way" before the infection reached it. This is the basis of periodontal disease---The loss of bone as a protective mechanism against a dangerous bone infection. Better the loss of the teeth than the premature loss of life!
Problems with the gingiva include the following medical conditions:
Gingivitis Periodontitis Acute Necrotizing Ulcerative Gingivitis Primary Herpetic Gingivostomatitis Gingival Hyperplasia or Enlargement Epulis (Localized gingival enlargement) Gingival Erosions.
It is the soft tissue that lies between the tooth and its bony socket. As you can see, 
it is really just a continuation of the connective tissue associated with the gingivo-dental fibers. In a healthy situation, there is never a direct attachment between the bone and the tooth itself. Such a direct attachment, when it occurs in pathological situations, is called ankylosis.
it is really just a continuation of the connective tissue associated with the gingivo-dental fibers. In a healthy situation, there is never a direct attachment between the bone and the tooth itself. Such a direct attachment, when it occurs in pathological situations, is called ankylosis.
The PDL is composed of fibrous connective tissue in which the fibers run approximately perpendicularly from the tooth surface to the bony socket. In any given area, a cross section looks like a tangled mass of nearly parallel fibers that attach at one end into the cementum overlying the root of the tooth, and at the other end, into the aveolar bone inside the socket.
The bone that supports the teeth is called alveolar bone. It's only purpose in life is to support the teeth, and if a tooth is extracted, the alveolar bone that originally 
supported it will eventually be reabsorbed by the body. The part of the alveolar bone that lines the socket is a thin layer of dense cortical bone called the lamina dura. The bone that underlies the lamina dura is cancellous bone (sometimes called medulary bone). Cancellous bone looks spongy and contains blood producing "organ" called bone marrow. In fact, all three of the features discussed in this section, the lamina dura, the periodontal ligament and the cancellous bone can be seen on any intraoral dental x-ray. In the x-ray seen on the left, follow the edge of any of the three teeth present from the top of the crown down into the bone. The dark line that separates the tooth from the bone represents the space where the periodontal ligament lives. The thin bright strip of bone directly beside the periodontal ligament space is the lamina dura. Under the lamina dura is the less bright cancellous bone. If you look carefully you can see the trabeculii --the tiny spicules of bone crisscrossing the cancellous bone that make it look spongy. These trabeculii separate the cancellous bone into tiny compartments which contain the blood producing marrow. These marrow spaces are seen in the colored image of the PDL above as bright "blobs".
supported it will eventually be reabsorbed by the body. The part of the alveolar bone that lines the socket is a thin layer of dense cortical bone called the lamina dura. The bone that underlies the lamina dura is cancellous bone (sometimes called medulary bone). Cancellous bone looks spongy and contains blood producing "organ" called bone marrow. In fact, all three of the features discussed in this section, the lamina dura, the periodontal ligament and the cancellous bone can be seen on any intraoral dental x-ray. In the x-ray seen on the left, follow the edge of any of the three teeth present from the top of the crown down into the bone. The dark line that separates the tooth from the bone represents the space where the periodontal ligament lives. The thin bright strip of bone directly beside the periodontal ligament space is the lamina dura. Under the lamina dura is the less bright cancellous bone. If you look carefully you can see the trabeculii --the tiny spicules of bone crisscrossing the cancellous bone that make it look spongy. These trabeculii separate the cancellous bone into tiny compartments which contain the blood producing marrow. These marrow spaces are seen in the colored image of the PDL above as bright "blobs".
he PDL acts like a shock absorber and transmits chewing forces from the tooth to the bone. It gives a little, like a water bed, so that the tooth can move in its socket. When alveolar bone is lost from gum disease, the total amount of PDL tissue holding the tooth is reduced and the tooth become increasingly loose. Loose teeth are a bad sign.
The periodontal ligament feels and sends pressure information to the brain when you bite. The PDL also feels pain. It tells the brain when you are biting down and the information is used to coordinate chewing. A tight ligament around the tooth also prevents bacterial invasion. A healthy PDL also protects the nerves and blood vessels contained in the area.
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