Misplaced Pages

Prognathism: Difference between revisions

Article snapshot taken from[REDACTED] with creative commons attribution-sharealike license. Give it a read and then ask your questions in the chat. We can research this topic together.
Browse history interactively← Previous editNext edit →Content deleted Content addedVisualWikitext
Revision as of 16:00, 17 October 2006 editDeeceevoice (talk | contribs)20,714 edits rev. anonymous vandalism← Previous edit Revision as of 16:25, 17 October 2006 edit undo84.178.244.112 (talk) what part of "greater number of intra-group variations than inter-group variations" don't you understand? See talkNext edit →
Line 1: Line 1:
The word '''prognathism''' derives from Greek ''pro'' (forward) and ''ganathos'' (jaw). Strictly speaking, the word refers to a faciocranial structure where the either the ] (upper) dental arch, or the ] (lower) dental arch, protrudes beyond the plane of the forehead. Alveolar prognathism is a protrusion of that portion of the maxilla where the teeth are located, in the dental lining of the upper jaw. Prognathism also can be used to describe ways that the maxillary and mandibular dental arches can relate to one another. ] often refer to this type of ] relationship as '''Skeletal Class III'''. When there is maxillary prognathism, the condition is called an ''overbite''. When the lower jaw extends beyond the upper, the condition commonly is called an ''underbite''.

The vast majority of prognathism in humans is due to normal variation among phenotypes. In human populations where prognathism is not the norm, it may be a malformation, the result of injury, a disease state or a hereditary condition.

==Use in forensic science and anthropology==

Humankind historically has been grouped into ] categories based on sets of phenotypical characteristics. While the concept of race has fallen into disfavor, certain clusters of phenotypical characteristics historically assigned to closely related human populations remain useful today in various archaeological and forensic disciplines. The degree to which prognathism is, or is not, present commonly is used today to help establish the relatedness of human populations, living and dead; their likely geographic origins; and, still, to assign racial classification. It is also one of many commonly utilized metrics in the identification of human remains, including in the field of forensic reconstruction.

Broadly speaking, prognathism is most common among ], ] and ], peoples whose ancestors were indigenous to ] (except for ] ]); ] peoples of ], ], various ]n populations and peoples of the ]n subcontinent. ] prognathism a forward projection of the dental lining, that portion of the maxilla where the teeth are rooted. Alveolar, as well as maxillary and mandibular prognathism are more common in these populations. ] peoples, generally considered indigenous to ] and nearby regions, commonly have an ], or flat profile, with ]s, or those indigenous to ], generally having prognathism to a moderate degree. There are, however, frequent exceptions to these broad categories, which defy narrow racial and/or ethnic classifications.

===Scientific racism and white supremacy===

A number of anthropologists of the nineteenth century believed that a classification into strict racial categories and the social development of peoples could be determined by measuring the facial angle, jaw structure and the shape of the human head. Further, they and asserted that people possessing the phenotypical characteristics associated with ] ''Caucasoids'', among them being a more orthognathous profile, were inherently superior to people with differing physical characteristics, because whites were more highly evolved than other races.

<blockquote>After Darwin popularized the idea that humans are descended from apes, the prognathous (protruding) jaw became a sign of lower development and of a closer relationship to primitive man. It also became the basis of much racial stereotyping of the Irish, and racial anthropologists argued that working class people were more prognathous than their social superiors- who were- self-flatteringly described as also biologically superior. In his very influential book, The Races of Man (1862), ], the future president of the Anthropological Institute, emphasized the vast difference between the prognathous (protruding) and orthognathous (less prominent) jawed people of Britain. These were terms originally The Irish, Welsh, and significantly, the lower class people, were among the prognathous, whereas all men of genius were orthognathous. (Beddoe also developed an Index of Nigressence, from which he argued that the Irish were close to Cro-Magnon man and thus had links with the "Africinoid" races!) These activities were reminiscent of Pieter Camper's theory of a 'facial angle'. One should emphasize, however, that such craniological and anthropometric studies "always represented a minority" of the papers presented at the Anthropological Institute, 1871-1899. These late nineteenth-century anatomical and anthropological descriptions of 'races' and their characteristics, measurements etc. were later the inspiration for the sort of mid twentieth-century racial anthropology as promulgated in Nazi Germany. (Anthony S. Wohl )</blockquote>

==Abnormal manifestations==
{{Infobox_Disease | {{Infobox_Disease |
Name = {{PAGENAME}} | Name = {{PAGENAME}} |
Line 30: Line 13:
MeshID = D011378 | MeshID = D011378 |
}} }}
{{Expert}}


The word '''prognathism''' derives from Greek ''pro'' (forward) and ''ganathos'' (jaw). If strictly applied, this word refers to conditions where the ] (lower) dental arch seems to be more protruded with respect to the ] (upper) dental arch. Prognathism refers to one possible way that the maxillary and mandibular dental arches can relate together. ] often refer to this type of ] relationship as '''Skeletal Class III'''. It is popularly called an '''underbite'''.
] Prognathism in all its kinds can be a hereditary condition which develops during growth or may be, more seldomly, the result of injury or disease.. It exists to varying degrees and takes different forms.


]

Prognathism in all its kinds can be a hereditary condition which develops during growth or may be, more seldomly, the result of injury or disease.. It exists to varying degrees and takes different forms.

==Medical definitions==
===Alveolar prognathism=== ===Alveolar prognathism===
]


An alveolar prognathism is limited to the dento-alveolar region of the jaw. It can be limited to one jaw or to both of them (biprotrusion). In these cases the front teeth are inclined forward. An alveolar prognathism is limited to the dento-alveolar region of the jaw. It can be limited to one jaw or to both of them (biprotrusion). In these cases the front teeth are inclined forward.
Line 43: Line 33:
Alveolar prognathism can be easily corrected also with fixed orthodontic therapy. Alveolar prognathism can be easily corrected also with fixed orthodontic therapy.
However, relapse is quite common, unless the cause is removed or a long term retention is used. However, relapse is quite common, unless the cause is removed or a long term retention is used.










===Maxillary prognathism=== ===Maxillary prognathism===
] ]

Maxillary prognathism is a protrusion of the maxilla, and is also a common feature of many populations. It affects a large area of the face, causing it to jut out, thereby increasing the facial area. In disease states, it is associated with de Lange Syndrome.
False maxillary prognathism, where there is a lack of growth of the mandible, is by far a more common condition.

Prognathism, if not extremely severe, can be treated in growing patients with orthodontic functional or orthopaedic appliances. In adult patients this condition can be corrected by means of a combined surgical/orthodontic treatment, where most of the time a mandibular advancement is performed.











Maxillary prognathism is a protrusion of the maxilla and, as noted above, is also a common feature of many human populations. It affects a large area of the face, causing it to jut out, thereby increasing the facial area. In disease states, it is associated with de Lange Syndrome.
False maxillary prognathism, where there is a lack of growth of the mandible, is by far a more common malformation.


Abnormal prognathism, if not extremely severe, can be treated in growing patients with orthodontic functional or orthopaedic appliances. In adult patients, this condition can be corrected by means of a combined surgical/orthodontic treatment, in most cases, a mandibular advancement.


===Mandibular prognathism (Progenism)=== ===Mandibular prognathism (Progenism)===


] ]
Pathologic ] prognathism is a disfiguring, genetic disorder where the lower ] outgrows the upper, resulting in an extended chin. ] prognathism is a disfiguring, genetic disorder where the lower ] outgrows the upper, resulting into an extended chin.


The condition is colloquially referred to as '''Habsburg jaw''', '''Habsburg lip''' or '''Austrian Lip''' (see ]) due to its prevalence in that ]. The trait is easily traceable in portraits of Habsburg family members. This has provided tools for people interested in studying ] and ] analysis. The condition is colloquially referred to as '''Habsburg jaw''', '''Habsburg lip''' or '''Austrian Lip''' (see ]) due to its prevalence in that ]. The trait is easily traceable in portraits of Habsburg family members. This has provided tools for people interested in studying ] and ] analysis.


It is alleged to have been derived through a female from the princely ] family of ]s, its ]n branch. The deformation of lips is clearly visible on tomb sculptures of Mazovian Piasts in Warsaw and was, perhaps, first observed in ] (1459-1519). It is alleged to have been derived through a female from the princely ] family of ]s, its ]n branch. The deformation of lips is clearly visible on tomb sculptures of Mazovian Piasts in Warsaw. However this may be, we have at least good evidence that the remark is of old date. It is perhaps first observed in ] (1459-1519).


Traits such as these that were common to royal families are believed to have been passed on and exaggerated over time through ] which caused extreme ]. Due to the common custom of politically motivated intermarriage among Habsburgs, the dynasty was virtually unparalleled in the degree of its inbreeding. ] is said to have had the most pronounced case of the Habsburg jaw on record. His jaw was so deformed that he was unable to chew. Traits such as these that were common to royal families are believed to have been passed on and exaggerated through ] which caused massive ]. Due to the large amount of politically motivated intermarriage between Habsburgs, the dynasty was virtually unparalleled in the degree of its inbreeding. ] is said to have had the most pronounced case of the Habsburg jaw on record (his jaw was so deformed that he was unable to chew).


Many dog breeds have underbite, particularly those with short faces. These can get caught in their jowls. Many dog breeds have underbite, particularly those with short faces. These can get caught in their jowls.
<br clear=all> <br clear=all>


==Racial or ethnic anthropology==
====Notable people with abnormal mandibular prognathism====
Most types of prognathism in humans as well as orthognathous profiles are normal variations among phenotypes and occur frequently in various populations with a greater number of intra-group variations (differences between sub-groups within the groups) than inter-group variations (physical differences between groups). Nevertheless, a number of anthropologists of the nineteenth-century believed that a classification in racial categories and their social development could be determined by measuring the facial angle, jaw structure and the shape of the head of humans, and claimed that people with a more orthognathous profile were superior to other cultures because they had "evolved" more than other races.

<blockquote>After Darwin popularized the idea that humans are descended from apes, the prognathous (protruding) jaw became a sign of lower development and of a closer relationship to primitive man. It also became the basis of much racial stereotyping of the Irish, and racial anthropologists argued that working class people were more prognathous than their social superiors- who were- self-flatteringly described as also biologically superior. In his very influential book, The Races of Man (1862), ], the future president of the Anthropological Institute, emphasized the vast difference between the prognathous (protruding) and orthognathous (less prominent) jawed people of Britain. These were terms originally The Irish, Welsh, and significantly, the lower class people, were among the prognathous, whereas all men of genius were orthognathous. (Beddoe also developed an Index of Nigressence, from which he argued that the Irish were close to Cro-Magnon man and thus had links with the "Africinoid" races!) These activities were reminiscent of Pieter Camper's theory of a 'facial angle'. One should emphasize, however, that such craniological and anthropometric studies "always represented a minority" of the papers presented at the Anthropological Institute, 1871-1899. These late nineteenth-century anatomical and anthropological descriptions of 'races' and their characteristics, measurements etc. were later the inspiration for the sort of mid twentieth-century racial anthropology as promulgated in Nazi Germany. (Anthony S. Wohl )</blockquote>

Modern forensic scientists and anthropologists outside the U.S. point out that trends in skeletal dimensions cannot be used for ascertaining racial differences between humans, but facial prognathism is still used by U.S. ] scientists and U.S. forensic ] as a key metric to estimate to which of the three judicially-enforced, appearance-based U.S. "racial" groups (Black, White, Yellow) human remains would have been assigned in life , with European populations estimated to have an orthognathous, or flat profile and northeast Asians having prognathism to a moderate degree. Among some sub-Saharan populations, Nilotic peoples, such as the Dinka of Somaliaas, and some of the people of ], alveolar and maxillary prognathism is said to be more pronounced, with large incisors and an often more pronouncedly receding chin line.

Maxillary prognathism was also one of the major criteria used by ], 20th-century America's most influential craniofacial anthropometrist, in his studies distinguishing Sub-Saharan "Caucasoids" (the people of Senegal, Gambia, Chad, Niger, Sudan, Ethiopia and Somalia) from what he called "Congoids."

==Notable people with the condition==
{{fact}} {{fact}}
*] suffered from the condition and was unable to chew as a result. *] suffered from the condition and was unable to chew as a result.

Revision as of 16:25, 17 October 2006

Medical condition
Prognathism
SpecialtyOrthodontics Edit this on Wikidata
This article needs attention from an expert on the subject. Please add a reason or a talk parameter to this template to explain the issue with the article.
When placing this tag, consider associating this request with a WikiProject.

The word prognathism derives from Greek pro (forward) and ganathos (jaw). If strictly applied, this word refers to conditions where the mandibular (lower) dental arch seems to be more protruded with respect to the maxillary (upper) dental arch. Prognathism refers to one possible way that the maxillary and mandibular dental arches can relate together. Orthodontists often refer to this type of maxillofacial relationship as Skeletal Class III. It is popularly called an underbite.

File:Prognathism.jpg

Prognathism in all its kinds can be a hereditary condition which develops during growth or may be, more seldomly, the result of injury or disease.. It exists to varying degrees and takes different forms.

Medical definitions

Alveolar prognathism

Alveolar prognathism, caused by thumb sucking and tongue thrust in a 7 yr old girl.

An alveolar prognathism is limited to the dento-alveolar region of the jaw. It can be limited to one jaw or to both of them (biprotrusion). In these cases the front teeth are inclined forward. Alveolar prognathism can be combined to maxillary or mandibular prognathism.

Harmful habits, such as thumb sucking or tongue thrusting can result in or exaggerate an alveolar prognathism, causing teeth to misalign. Functional appliances can be used in growing children to help modify bad habits and neuro-muscular function, with the aim of correcting this condition.

Alveolar prognathism can be easily corrected also with fixed orthodontic therapy. However, relapse is quite common, unless the cause is removed or a long term retention is used.





Maxillary prognathism

File:Class2profile.jpg
10 year old boy with false maxillary prognathism

Maxillary prognathism is a protrusion of the maxilla, and is also a common feature of many populations. It affects a large area of the face, causing it to jut out, thereby increasing the facial area. In disease states, it is associated with de Lange Syndrome. False maxillary prognathism, where there is a lack of growth of the mandible, is by far a more common condition.

Prognathism, if not extremely severe, can be treated in growing patients with orthodontic functional or orthopaedic appliances. In adult patients this condition can be corrected by means of a combined surgical/orthodontic treatment, where most of the time a mandibular advancement is performed.







Mandibular prognathism (Progenism)

Philip IV of Spain displaying the prominent Habsburg lip and jaw.

Mandibular prognathism is a disfiguring, genetic disorder where the lower jaw outgrows the upper, resulting into an extended chin.

The condition is colloquially referred to as Habsburg jaw, Habsburg lip or Austrian Lip (see Habsburg) due to its prevalence in that bloodline. The trait is easily traceable in portraits of Habsburg family members. This has provided tools for people interested in studying genetics and pedigree analysis.

It is alleged to have been derived through a female from the princely Polish family of Piasts, its Masovian branch. The deformation of lips is clearly visible on tomb sculptures of Mazovian Piasts in Warsaw. However this may be, we have at least good evidence that the remark is of old date. It is perhaps first observed in Maximilian I (1459-1519).

Traits such as these that were common to royal families are believed to have been passed on and exaggerated through royal intermarriage which caused massive inbreeding. Due to the large amount of politically motivated intermarriage between Habsburgs, the dynasty was virtually unparalleled in the degree of its inbreeding. Charles II of Spain is said to have had the most pronounced case of the Habsburg jaw on record (his jaw was so deformed that he was unable to chew).

Many dog breeds have underbite, particularly those with short faces. These can get caught in their jowls.

Racial or ethnic anthropology

Most types of prognathism in humans as well as orthognathous profiles are normal variations among phenotypes and occur frequently in various populations with a greater number of intra-group variations (differences between sub-groups within the groups) than inter-group variations (physical differences between groups). Nevertheless, a number of anthropologists of the nineteenth-century believed that a classification in racial categories and their social development could be determined by measuring the facial angle, jaw structure and the shape of the head of humans, and claimed that people with a more orthognathous profile were superior to other cultures because they had "evolved" more than other races.

After Darwin popularized the idea that humans are descended from apes, the prognathous (protruding) jaw became a sign of lower development and of a closer relationship to primitive man. It also became the basis of much racial stereotyping of the Irish, and racial anthropologists argued that working class people were more prognathous than their social superiors- who were- self-flatteringly described as also biologically superior. In his very influential book, The Races of Man (1862), John Beddoe, the future president of the Anthropological Institute, emphasized the vast difference between the prognathous (protruding) and orthognathous (less prominent) jawed people of Britain. These were terms originally The Irish, Welsh, and significantly, the lower class people, were among the prognathous, whereas all men of genius were orthognathous. (Beddoe also developed an Index of Nigressence, from which he argued that the Irish were close to Cro-Magnon man and thus had links with the "Africinoid" races!) These activities were reminiscent of Pieter Camper's theory of a 'facial angle'. One should emphasize, however, that such craniological and anthropometric studies "always represented a minority" of the papers presented at the Anthropological Institute, 1871-1899. These late nineteenth-century anatomical and anthropological descriptions of 'races' and their characteristics, measurements etc. were later the inspiration for the sort of mid twentieth-century racial anthropology as promulgated in Nazi Germany. (Anthony S. Wohl )

Modern forensic scientists and anthropologists outside the U.S. point out that trends in skeletal dimensions cannot be used for ascertaining racial differences between humans, but facial prognathism is still used by U.S. forensic scientists and U.S. forensic anthropologists as a key metric to estimate to which of the three judicially-enforced, appearance-based U.S. "racial" groups (Black, White, Yellow) human remains would have been assigned in life , with European populations estimated to have an orthognathous, or flat profile and northeast Asians having prognathism to a moderate degree. Among some sub-Saharan populations, Nilotic peoples, such as the Dinka of Somaliaas, and some of the people of Melanesia, alveolar and maxillary prognathism is said to be more pronounced, with large incisors and an often more pronouncedly receding chin line.

Maxillary prognathism was also one of the major criteria used by Carleton Coon, 20th-century America's most influential craniofacial anthropometrist, in his studies distinguishing Sub-Saharan "Caucasoids" (the people of Senegal, Gambia, Chad, Niger, Sudan, Ethiopia and Somalia) from what he called "Congoids."

Notable people with the condition

Categories:
Prognathism: Difference between revisions Add topic