إدارة الموسوعة 1: مراجعة واحدة

2016-11-14T04:10:02Z

مراجعة واحدة

صفحة جديدة

{{Other uses|Diastema (disambiguation)}}
{{Infobox anatomy
| Name = Diastema
| Latin = diastema
| Greek =
| GraySubject =
| GrayPage =
| Image = Crâne cheval.jpg
| Caption = Large diastemata between incisors, canines and molars of a normal [[horse]]
| Width =
}}
A '''diastema''' (plural '''diastemata''') is a space or gap between two [[teeth]]. Many species of [[mammals]] have diastemata as a normal feature, most commonly between the [[incisor]]s and [[Molar (tooth)|molars]]. Diastemata are common for children and can exist in adult teeth as well. Diastemata are primarily caused by imbalance in the relationship between the jaw and the size of teeth. If the labial frenulum (lip tissue) pulls, it can also push the teeth apart and cause a diastema between the center of the two front teeth.

==In humans==
[[File:Terry-Thomas, 1961.jpg|thumb|left|Actor [[Terry-Thomas]] was known for his 1⁄3-inch (8.5 mm) diastema.]]
In humans, the term is most commonly applied to an open space between the upper [[incisor]]s (front teeth). It happens when there is an unequal relationship between the size of the teeth and the [[jaw]].

Diastema is sometimes caused or exacerbated by the action of a labial [[frenulum]] (the tissue connecting the lip to the gum) causing high mucosal attachment and less attached keratinized tissue which is more prone to recession or by tongue thrusting, which can push the teeth apart.

In the ''[[Canterbury Tales]]'', [[Geoffrey Chaucer]] wrote of the "[[The Wife of Bath's Prologue and Tale|gap-toothed wife of Bath]]".<ref name=gap>{{cite news |author=Rachel Dodes |coauthors= |title=We Don't Mind the Gap: The Fashionable Flash a New Smile |url=http://online.wsj.com/article/SB10001424052748703720004575478213601248720.html?mod=WSJ_NewYork_NewsReel |quote= |work=[[Wall Street Journal]] |date=September 8, 2010 |accessdate=2010-09-10 }}</ref> As early as this time period, the gap between the front teeth, especially in women, was associated with lustful characteristics. Thus, the implication in describing "the gap-toothed wife of Bath" is that she is a middle-aged woman with insatiable lust. This has no scientific basis, but it has been a common premise in folklore since the Middle Ages.{{Citation needed|date=August 2009}}

In [[Ghana]], [[Namibia]] and [[Nigeria]], diastemata are regarded as being attractive and a sign of fertility, and some people have even had them created through [[cosmetic dentistry]].<ref name=bite>{{cite web|url=http://bitemagazine.com.au/news_blog/?p=190|title=Midline diastemata in fashion|publisher=''Bite'' magazine website|date=October 14, 2010|accessdate=September 10, 2010|archiveurl=https://web.archive.org/web/20120420151357/http://bitemagazine.com.au/news_blog/?p=190|archivedate=April 20, 2012}}</ref>
In France, they are called "dents du bonheur" ("lucky teeth").<ref>{{cite web|url=http://www.metro.us/newyork/national/article/714520--the-year-of-the-gap-tooth-trend|last=McGuiness|first=Romina|title=The year of the gap-tooth trend|work=Metro|date=December 8, 2010|accessdate=April 17, 2013|archiveurl=https://web.archive.org/web/20120308144534/http://www.metro.us/newyork/national/article/714520--the-year-of-the-gap-tooth-trend|archivedate=March 8, 2012}}</ref> This expression originated in Napoleon's time: when the Napoleonic army recruited, it was imperative that soldiers had incisors in perfect condition because they had to open their powder magazine with the teeth in order to recharge their rifles that they had to hold with their two hands. All those who had teeth apart were then classified as unfit to fight. Some men broke their own teeth to avoid going to war.{{cn|date=August 2015}} [[Les Blank]]'s ''[[Gap-Toothed Women]]'' is a documentary film about diastematic women.

Some well-known people noted for having diastema include country music singer [[Charley Pride]], models [[Jessica Hart (model)|Jessica Hart]], [[Lindsey Wixson]], [[Lauren Hutton]] and [[Lara Stone]], American television news reporter and anchor [[Michelle Charlesworth]], [[American football]] player [[Michael Strahan]], actresses [[Vanessa Paradis]], [[Léa Seydoux]], [[Amira Casar]], [[Eve Myles]], [[Cecile de France]], [[Béatrice Dalle]], [[Jorja Fox]], [[Anna Paquin]] and [[Uzo Aduba]], singer/guitarist [[Ray Davies]] of the [[Kinks]], musician Elvis Costello, actors [[Ernest Borgnine]], [[Terry-Thomas]], and Jamaica's [[Shebada]], singers [[Madonna (entertainer)|Madonna]], [[Melanie Martinez (singer)|Melanie Martinez]], [[Becky G]], and [[Laura Pausini]], singer-songwriters [[Elton John]], [[Mac Demarco]] and [[Seal (musician)|Seal]], rock musician [[Flea (musician)|Flea]], rapper [[50 Cent]], former late night show host [[David Letterman]], guitarist [[Steve Howe (musician)|Steve Howe]],<ref>{{cite web |url=http://www.allmusic.com/artist/steve-howe-mn0000036537 |title=Steve Howe |author=Gary Hill |work=AllMusic |accessdate=July 23, 2014}}</ref> comedian [[Paul F. Tompkins]],<ref>{{cite web|title=Diastema (dentistry) |publisher=Factualworld |url=http://www.factualworld.com/article/Diastema_(dentistry) |accessdate=3 Apr 2014}}</ref> professional wrestler and former TNA World Heavyweight Champion [[Bobby Roode]], [[Major League Baseball]] player [[Jimmy Rollins]], singer [[Bobby Brown]] and his daughter [[Bobbi Kristina Brown]] and former U.S. Secretary of State [[Condoleezza Rice]].<ref name=gap/><ref name=bite/>

===Dental corrections===
[[File:Braces Close Diastema Spaces.jpg|thumb|100px|Typical sequence of diastema correction using orthodontic braces.]]
Diastema is an adjustable dental condition. This includes traditional [[Dental braces|braces]], [[Invisalign]], dental bands or direct dental bonding to make the teeth wider and thus fill up the space. One problem with orthodontic correction is relapse: there is a strong propensity for the gap to reappear after treatment.{{Citation needed|date=January 2011}} This can be addressed by bonding a permanent retainer to the inside surfaces of the teeth.

==Other animals==
Most species of [[herbivorous]] mammals have a diastema between the front teeth ([[incisors]] and [[canine tooth|canines]]), if present, and the cheek teeth ([[molars]] and [[premolars]]). This is the case, for example, for [[rodents]] and [[lagomorphs]], as well as for most [[ungulate]]s.

Many [[Myrmecophagy|myrmecophagous]] mammals, such as the [[aardwolf]], [[anteaters]] and [[pangolin]], have either no teeth, or, in cases like the aardwolf, have large diastemata between their sparse teeth.

==See also==
{{Portal|Dentistry}}
*[[Cosmetic dentistry]]
*[[Tooth veneers]]

==References==
{{Reflist}}

[[Category:Vertebrate anatomy]]
[[Category:Human anatomy]]
[[Category:Teeth]]
[[Category:Developmental tooth pathology]]

[[de:Diastema]]
[[fr:Diastème (odontologie)]]

Diastema - تاريخ المراجعة

إدارة الموسوعة 1: مراجعة واحدة