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Urtinotherium
''Urtinotherium'' (meaning "Urtyn beast") is an extinct genus of paracerathere mammals. It was a large animal that was closely related to ''Paraceratherium'', and found in rocks dating from the Late Eocene to Early Oligocene period. The remains were first discovered in the Urtyn Obo region (now Dorbod Banner, Ulanqab) in Inner Mongolia, which the name ''Urtinotherium'' is based upon. Other referred specimens are from northern China. Description ''Urtinotherium'' was a representative of the large family Paraceratheriidae, and almost reached the proportions of ''Paraceratherium''. It is known from several findings in central and eastern Asia, though no complete skeletons are known. The holotype fossil (catalog number IVPP V.2769) includes a complete lower jaw in length, comparable to the smallest known of ''Paraceratherium''. The jaw is wedge shaped, very low in height, and with elongated branches. The symphysis was solid and extended to the beginning of the second premolars. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paraceratherium
''Paraceratherium'' is an extinct genus of hornless rhinoceros. It is one of the largest terrestrial mammals that has existed and lived from the early to late Oligocene epoch (34–23 million years ago). The first fossils were discovered in what is now Pakistan, and remains have been found across Eurasia between China and the Balkans. It is classified as a member of the family Paraceratheriidae. ''Paraceratherium'' means "near the hornless beast", in reference to ''Aceratherium'', the genus in which the type species ''P. bugtiense'' was originally placed. The exact size of ''Paraceratherium'' is unknown because of the incompleteness of the fossils. The shoulder height was about , and the length about . Its weight is estimated to have been about . The long neck supported a skull that was about long. It had large, tusk-like incisors and a nasal incision that suggests it had a prehensile upper lip or proboscis (trunk). The legs were long and pillar-like. The lifestyle of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indricotherium
''Paraceratherium'' is an extinct genus of hornless rhinoceros. It is one of the largest terrestrial mammals that has existed and lived from the early to late Oligocene epoch (34–23 million years ago). The first fossils were discovered in what is now Pakistan, and remains have been found across Eurasia between China and the Balkans. It is classified as a member of the family Paraceratheriidae. ''Paraceratherium'' means "near the hornless beast", in reference to ''Aceratherium'', the genus in which the type species ''P. bugtiense'' was originally placed. The exact size of ''Paraceratherium'' is unknown because of the incompleteness of the fossils. The shoulder height was about , and the length about . Its weight is estimated to have been about . The long neck supported a skull that was about long. It had large, tusk-like incisors and a nasal incision that suggests it had a prehensile upper lip or proboscis (trunk). The legs were long and pillar-like. The lifestyle of ' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paraceratheriidae
Paraceratheriidae is an extinct family of long-limbed, hornless rhinocerotoids, commonly known as paraceratheres or indricotheres, that originated in the Eocene epoch and lived until the early Miocene. The first paraceratheres were only about the size of large dogs, growing progressively larger in the late Eocene and Oligocene. They were most common in the rainforest floodplain region which is now Kazakhstan, India, and southwest China, and lived further inland throughout northern and central Asia as well. The paraceratheres reached the peak of their evolution from the middle Oligocene to the early Miocene, where they became very large, herbivorous mammals. Most genera were about the size of modern draft horses and the extinct giant horse ''Equus giganteus'', with some growing significantly larger. The largest genus was ''Paraceratherium'', which was more than twice as heavy as a bull African elephant, and was one of the largest land mammals that ever lived. However, they remai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brachyodont
The molars or molar teeth are large, flat teeth at the back of the mouth. They are more developed in mammals. They are used primarily to grind food during chewing. The name ''molar'' derives from Latin, ''molaris dens'', meaning "millstone tooth", from ''mola'', millstone and ''dens'', tooth. Molars show a great deal of diversity in size and shape across mammal groups. The third molar of humans is sometimes vestigial. Human anatomy In humans, the molar teeth have either four or five cusps. Adult humans have 12 molars, in four groups of three at the back of the mouth. The third, rearmost molar in each group is called a wisdom tooth. It is the last tooth to appear, breaking through the front of the gum at about the age of 20, although this varies from individual to individual. Race can also affect the age at which this occurs, with statistical variations between groups. In some cases, it may not even erupt at all. The human mouth contains upper (maxillary) and lower (mandibu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crown (tooth)
In dentistry, crown refers to the anatomical area of teeth, usually covered by enamel. The crown is usually visible in the mouth after developing below the gingiva The gums or gingiva (plural: ''gingivae'') consist of the mucosal tissue that lies over the mandible and maxilla inside the mouth. Gum health and disease can have an effect on general health. Structure The gums are part of the soft tissue l ... and then erupting into place. If part of the tooth gets chipped or broken, a dentist can apply an artificial crown. Crowns are used most commonly to entirely cover a damaged tooth or cover an implant. Bridges are also used to cover a space if one or more teeth is missing. They are cemented to natural teeth or implants surrounding the space where the tooth once stood. There are various materials that can be used including a type of cement or stainless steel. The cement crowns look like regular teeth while the stainless steel crowns are silver or gold. References ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molar (tooth)
The molars or molar teeth are large, flat 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, te ... at the back of the mouth. They are more developed in mammal, mammals. They are used primarily to comminution, grind food during mastication, chewing. The name ''molar'' derives from Latin, ''molaris dens'', meaning "millstone tooth", from ''mola'', millstone and ''dens'', tooth. Molars show a great deal of diversity in size and shape across mammal groups. The third molar of humans is sometimes vestigial. Human anatomy In humans, the molar teeth have either four or five cusp (dentistry), cusps. Adult humans have 12 molars, in four groups of three at the back of the mouth. The third, rearmost molar in each group is called a Third molar, wisdom tooth. It is the last tooth to appear, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Premolar
The premolars, also called premolar teeth, or bicuspids, are transitional teeth located between the canine and molar teeth. In humans, there are two premolars per quadrant in the permanent set of teeth, making eight premolars total in the mouth. They have at least two cusps. Premolars can be considered transitional teeth during chewing, or mastication. They have properties of both the canines, that lie anterior and molars that lie posterior, and so food can be transferred from the canines to the premolars and finally to the molars for grinding, instead of directly from the canines to the molars. Human anatomy The premolars in humans are the maxillary first premolar, maxillary second premolar, mandibular first premolar, and the mandibular second premolar. Premolar teeth by definition are permanent teeth distal to the canines, preceded by deciduous molars. Morphology There is always one large buccal cusp, especially so in the mandibular first premolar. The lower sec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
China
China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's List of countries and dependencies by population, most populous country, with a Population of China, population exceeding 1.4 billion, slightly ahead of India. China spans the equivalent of five time zones and Borders of China, borders fourteen countries by land, the List of countries and territories by land borders, most of any country in the world, tied with Russia. Covering an area of approximately , it is the world's third List of countries and dependencies by area, largest country by total land area. The country consists of 22 provinces of China, provinces, five autonomous regions of China, autonomous regions, four direct-administered municipalities of China, municipalities, and two special administrative regions of China, Special Administrative Regions (Hong Kong and Macau). The national capital is Beijing, and the List of cities in China by population, most populous cit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tooth Enamel
Tooth enamel is one of the four major tissues that make up the tooth in humans and many other animals, including some species of fish. It makes up the normally visible part of the tooth, covering the crown. The other major tissues are dentin, cementum, and dental pulp. It is a very hard, white to off-white, highly mineralised substance that acts as a barrier to protect the tooth but can become susceptible to degradation, especially by acids from food and drink. Calcium hardens the tooth enamel. In rare circumstances enamel fails to form, leaving the underlying dentin exposed on the surface. Features Enamel is the hardest substance in the human body and contains the highest percentage of minerals (at 96%),Ross ''et al.'', p. 485 with water and organic material composing the rest.Ten Cate's Oral Histology, Nancy, Elsevier, pp. 70–94 The primary mineral is hydroxyapatite, which is a crystalline calcium phosphate. Enamel is formed on the tooth while the tooth develops wit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diastema
A diastema (plural diastemata, from Greek διάστημα, space) is a space or gap between two teeth. Many species of mammals have diastemata as a normal feature, most commonly between the incisors and molars. More colloquially, the condition may be referred to as gap teeth or tooth gap. In humans, the term is most commonly applied to an open space between the upper incisors (front teeth). It happens when there is an unequal relationship between the size of the teeth and the jaw. Diastemata are common for children and can exist in adult teeth as well. In humans Causes 1. Oversized Labial Frenulum: 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. This is more prone to recession or by tongue thrusting, which can push the teeth apart. 2. Periodontal Disease: Periodontal disease, also known as gum disease, can result in bone loss th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Juxia
''Juxia'' (from , usually refers to indricotheres) is an extinct genus of indricothere, a group of herbivorous mammals that are part of the odd-toed ungulate family tree of rhinoceros and tapirs. The type species is ''Juxia sharamurenensis'', named by Zhou Mingzhen and in 1964. ''Juxia'' was around the size of a horse. It lived in Asia during the upper Eocene The Eocene ( ) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', " .... As an early indricothere, ''Juxia'' had a relatively light body, held by elongated long legs and small skull firmly attached to a relatively long neck. Based on its triangular like teeth and sharp protruding incisors, ''Juxia'' was probably a strict browser, feeding on ferns and leaves on branches where most herbivorous mammals couldn't reach. In terms of habitat, ''Juxi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
