gum

or gingiva

Mucous-membrane-covered connective tissue attached to and surrounding the necks of the teeth and the alveolar bone of the jaw. The edges of the gums around the teeth are free and extend into the spaces between the teeth. Fibres of the ligament that holds the teeth in their sockets enter the gum and hold it tightly against the teeth. Pink, speckled, and tough, healthy gums have limited sensitivity to pain, temperature, and pressure. Changes in colour, loss of speckling, or abnormal sensitivity are early signs of gingivitis, in which pockets form between the gum and teeth and become infected, with inflammation, bleeding, and, in severe cases, loss of teeth.

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Sweetened product made from chicle and similar resilient substances that is chewed for its flavour. Tree resins have been chewed as teeth cleaners and breath fresheners since ancient times. The latex (called chicle) of the Central American sapodilla tree was first used to mass-produce chewing gum in the 19th century; its plasticity, insolubility in water, and ability to hold a flavour made it an ideal chewing-gum base. After World War II other gums and synthetic rubbers came to replace chicle.

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The gingiva (sing. and plur.: gingiva), or gums, consists of the mucosal tissue that lies over the alveolar bone.

General description

Gingiva are part of the soft tissue lining of the mouth. They surround the teeth and provide a seal around them. Compared with the soft tissue linings of the lips and cheeks, most of the gingiva are tightly bound to the underlying bone and are designed to resist the friction of food passing over them. Healthy gingiva is usually coral pink, but may contain physiologic pigmentation. Changes in color, particularly increased redness, together with edema and an increased tendency to bleed, suggest an inflammation that is possibly due to the accumulation of bacterial plaque.

Subdivisions of gingiva

The gingiva is divided anatomically into marginal, attached and interdental areas.

Marginal gingiva

The marginal gingiva is the terminal edge of gingiva surrounding the teeth in collar like fashion. In about 50% of individuals, it is demarcated from the adjacent, attached gingiva by a shallow linear depression, the free gingival groove. Usually about 1 mm wide, it forms the soft tissue wall of the gingival sulcus. The marginal gingiva is supported and stabilized by the gingival fibers.

Attached gingiva

The attached gingiva is continuous with the marginal gingiva. It is firm, resilient, and tightly bound to the underlying periosteum of alveolar bone. The facial aspect of the attached gingiva extends to the relatively loose and movable alveolar mucosa, from which it is demarcated by the mucogingival junction. Attached gingiva may present with surface stippling.

Interdental gingiva

The interdental gingiva occupies the gingival embrasure, which is the interproximal space beneath the area of tooth contact. The interdental gingiva can be pyramidal or have a "col" shape.

Diseases of the gingiva

The gingival cavity microecosystem, fueled by food residues and saliva, can support the growth of many microorganisms, of which some can be injurious to health. Improper or insufficient oral hygiene can thus lead to many gingival and periodontal disorders, including gingivitis or pyorrhea, which are major causes for tooth failure. Recent studies have also shown that Anabolic steroids are also closely associated with gingival enlargement requiring a gingivectomy for many cases.

Characteristics of healthy gingiva

Color

Healthy gingiva usually has a color that has been described as "coral pink." Other colours like red, white, and blue can signify inflammation (gingivitis) or pathology. Although the text book color of gingiva is "coral pink", normal racial pigmentation makes the gingiva appear darker. Because the color of gingiva varies due to racial pigmentation, uniformity of color is more important than the underlying color itself.

Contour

Healthy gingiva has a smooth arcuate or scalloped appearance around each tooth. Healthy gingiva fills and fits each interdental space, unlike the swollen gingiva papilla seen in gingivitis or the empty interdental embrasure seen in periodontal disease. Healthy gums hold tight to each tooth in that the gingival surface narrows to "knife-edge" thin at the free gingival margin. On the other hand, inflamed gums have a "puffy" or "rolled" margin.

Texture

Healthy gingiva has a firm texture that is resistant to movement, and the surface texture often exhibits surface stippling. Unhealthy gingiva, on the other hand, is often swollen and mushy.

Reaction to disturbance

Healthy gums usually have no reaction to normal disturbance such as brushing or periodontal probing. Unhealthy gums on the other hand will show bleeding on probing (BOP) and/or purulent exudate (pus).

Additional images

See also

• Head and neck anatomy
• Periodontitis
• Gum graft

Sources

• Willmann, Donald. PERI 5081 - Freshman Periodontics. UTHSCSA, 2006. 2.3.1

External links

• Periodontal disease