''Angularis nigra'', Latin for 'black angle', also known as open gingival embrasures, and colloquially known as "black triangle", is the space or gap seen at the cervical

embrasure An embrasure (or crenel or crenelle; sometimes called gunhole in the domain of Age of Gunpowder, gunpowder-era architecture) is the opening in a battlement between two raised solid portions (merlons). Alternatively, an embrasure can be a sp ...

, below the contact point of some

teeth A tooth (: teeth) is a hard, calcified structure found in the jaws (or mouths) of many vertebrates and used to break down food. Some animals, particularly carnivores and omnivores, also use teeth to help with capturing or wounding prey, tear ...

. The

interdental papilla The interdental papilla, also known as the interdental gingiva, is the part of the gums (gingiva) that exists coronal to the free gingival margin on the mesial and distal surfaces of the teeth. The interdental papillae fill in the area betw ...

does not fully enclose the space, leading to an aperture between adjacent teeth. This gap has many causes including gingival recession, and gingival withdrawal post-orthodontic work. Interdental "black triangles" were rated as the third-most-disliked aesthetic problem below caries and crown margins. Treatment of ''angularis nigra'' often requires an interdisciplinary approach, involving periodontal, orthodontic and restorative treatment. Possible treatments to correct ''angularis nigra'' include addition of

composite resin Dental composite resins (better referred to as "resin-based composites" or simply "filled resins") are dental cements made of synthetic resins. Synthetic resins evolved as restorative materials since they were insoluble, of good tooth-like appe ...

in the space,

veneer Veneer may refer to: Materials * Masonry veneer, a thin facing layer of brick * Stone veneer, a thin facing layer of stone * Veneer (dentistry), a cosmetic treatment for teeth * Wood veneer, a thin facing layer of wood Arts and entertainment * ' ...

placement, or gum graft. ''Angularis nigra'' is generally only treated based on the aesthetic preference of the patient (although serious gum recession may warrant periodontal treatment). Previously, lack of proper terminology to report this condition was an issue, often colloquially termed the "black triangle"; ''angularis nigra'' has been proposed as a term to describe the appearance. There are several risk factors leading to the development of black triangles. Papillae dimension can be changed due to any of the following reasons: 1. Inter-proximal space between teeth; diverging roots can result in the presence of an interproximal space when the contact point between the two clinical crowns is situated too incisally, diverging roots may also be a result of orthodontic treatment. 2. The increased distance between inter-proximal contact position to bone crest, example to that is the naturally occurring diastema. 3. Gingiva biotype; thick and thin tissues often respond differently to inflammation and trauma, thin gingiva is more liable to recession following restoration / crown preparation / periodontal or implant surgery. 4. Patient's age; the gingiva recede with aging which can cause an open gingival embrasure. 5.

Periodontal disease Periodontal disease, also known as gum disease, is a set of inflammatory conditions affecting the tissues surrounding the teeth. In its early stage, called gingivitis, the gums become swollen and red and may bleed. It is considered the main c ...

and loss of attachment, resulting in recession. 6. Tooth morphology and abnormal

crown A crown is a traditional form of head adornment, or hat, worn by monarchs as a symbol of their power and dignity. A crown is often, by extension, a symbol of the monarch's government or items endorsed by it. The word itself is used, parti ...

and restoration shape; a clinical crown that tends to be triangular in shape can also result in partial interproximal space.

References

External links

*https://web.archive.org/web/20101219042017/http://www.1stcosmeticdentist.com/restorative-dentistry-article33.html *https://web.archive.org/web/20110505195404/http://www.thordarson.ca/black-triangles-between-tooth Mouth

References

Further reading

External links