Human tooth development

83: 768: 1164: 969:, into their immediate surrounding. The organic matrix contains the material needed for dentin formation. As odontoblasts deposit organic matrix termed predentin, they migrate toward the center of the dental papilla. Thus, unlike enamel, dentin starts forming in the surface closest to the outside of the tooth and proceeds inward. Cytoplasmic extensions are left behind as the odontoblasts move inward. The unique, tubular microscopic appearance of dentin is a result of the formation of dentin around these extensions. 1102: 920: 75: 949: 866:. Cells on the periphery of the enamel organ separate into four important layers. Cuboidal cells on the periphery of the dental organ are known as outer enamel epithelium (OEE). The columnar cells of the enamel organ adjacent to the enamel papilla are known as inner enamel epithelium (IEE). The cells between the IEE and the stellate reticulum form a layer known as the stratum intermedium. The rim of the enamel organ where the outer and inner enamel epithelium join is called the 157: 897:. The "field model" proposes there are components for each type of tooth shape found in the ectomesenchyme during tooth development. The components for particular types of teeth, such as incisors, are localized in one area and dissipate rapidly in different parts of the mouth. Thus, for example, the "incisor field" has factors that develop teeth into incisor shape, and this field is concentrated in the central incisor area, but decreases rapidly in the canine area. 845: 1275:. Hemidesmosomes provide anchorage between cells through small filament-like structures provided by the remnants of ameloblasts. Once this occurs, junctional epithelium forms from reduced enamel epithelium, one of the products of the enamel organ, and divides rapidly. This results in the perpetually increasing size of the junctional epithelial layer and the isolation of the remnants of ameloblasts from any source of nutrition. As the ameloblasts degenerate, a 885: 776: 829: 982: 1335:

the tooth is pushed upward into the mouth by the growth of the tooth's root, (2) the tooth is pushed upward by the growth of the bone around the tooth, (3) the tooth is pushed upward by vascular pressure, and (4) the tooth is pushed upward by the cushioned hammock. The cushioned hammock theory, first proposed by Harry Sicher, was taught widely from the 1930s to the 1950s. This theory postulated that a

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by regional odontodysplasia nevAmelogenesis imperfecta is an autosomal dominant disease characterized by a defect in dental enamel formation. Teeth are often free of enamel, small, misshapen, and tinted brown. The cause of these deformities is due to a mutation in enamel in expression. Dental patients with this disease should be especially cautious and visit their dentist frequently.

1450:. Since there are no premolars in the primary dentition, the primary molars are replaced by permanent premolars. If any primary teeth are lost before permanent teeth are ready to replace them, some posterior teeth may drift forward and cause space to be lost in the mouth. This may cause crowding and/or misplacement once the permanent teeth erupt, which is usually referred to as 901:

lamina continues in an area called the "progress zone". Once the progress zone travels a certain distance from the first tooth bud, a second tooth bud will start to develop. These two models are not necessarily mutually exclusive, nor does widely accepted dental science consider them to be so: it is postulated that both models influence tooth development at different times.

1220:, which is the arrangement of teeth and how teeth in opposite arches come in contact with one another, continually affects the formation of periodontal ligament. This perpetual creation of periodontal ligament leads to the formation of groups of fibers in different orientations, such as horizontal and oblique fibers. 1967:

in females than males. The most common location is the mandibular region of the central incisors. Natal teeth and neonatal teeth are associated with genetics, developmental abnormalities and certain recognized syndromes. Additional names for this condition include precocious dentition, baby teeth, and milk teeth.

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child's tooth development being obstructed. Those children are shown to be prone to incisor and first molar hypomineralization, a weakened state of the enamel. Additionally, it is most important for mother's to avoid BPA during pregnancy, but also avoid BPA-use in the child's products up to five months of age.

1764:, as Vitamin C is for collagen. Fluoride, although not a nutrient, is incorporated into the hydroxyapatite crystal of a developing tooth and bones. The dental theory is the low levels of fluoride incorporation and very mild fluorosis makes the tooth more resistant to demineralization and subsequent decay. 1382:, and (5) second molar. As a general rule, four teeth erupt for every six months of life, mandibular teeth erupt before maxillary teeth, and teeth erupt sooner in females than males. During primary dentition, the tooth buds of permanent teeth develop below the primary teeth, close to the palate or tongue. 1966:

Natal and neonatal teeth are an anomaly that involves teeth erupting in a newborn infant's mouth earlier than usual. The incidence ranges from 1:2,000 to 1:3,500 births. Natal teeth are more frequent, approximately three times more common than neonatal teeth. Some authors reported a higher prevalence

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Bisphenol A (BPA) is a hormone-disrupting chemical that has been implicated in having negative effects on human health, including, but not limited to, fetal development. As shown in animal studies which mimic human enamel, the mother's consumption of products with BPA during pregnancy can lead to the

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Mixed dentition starts when the first permanent molar appears in the mouth, usually at six years, and lasts until the last primary tooth is lost, usually at eleven or twelve years. Permanent teeth in the maxilla erupt in a different order from permanent teeth on the mandible. Maxillary teeth erupt in

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from periodontal ligaments attached to a tooth moving away from it has a high number of osteoblasts, resulting in bone formation. Thus, the tooth or teeth are slowly moved along the jaw so as to achieve a dentition that works in harmony. In this way, the width of the space between the alveoli and the

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into odontoblasts, which are the cells that form dentin. Researchers believe that the odontoblasts would not form if it were not for the changes occurring in the IEE. As the changes to the IEE and the formation of odontoblasts continue from the tips of the cusps, the odontoblasts secrete a substance,

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Tooth eruption occurs when the teeth enter the mouth and become visible. Although researchers agree that tooth eruption is a complex process, there is little agreement on the identity of the mechanism that controls eruption. Some commonly held theories that have been disproven over time include: (1)

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Dentin formation, known as dentinogenesis, is the first identifiable feature in the crown stage of tooth development. The formation of dentin must always occur before the formation of enamel. The different stages of dentin formation result in different types of dentin: mantle dentin, primary dentin,

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Enamel formation is called amelogenesis and occurs in the crown stage (advanced bell stage) of tooth development. "Reciprocal induction" governs the relationship between the formation of dentin and enamel; dentin formation must always occur before enamel formation. Generally, enamel formation occurs

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In summary, the layers in order of innermost to outermost consist of dentin, enamel (formed by IEE, or 'ameloblasts', as they move outwards/upwards), inner enamel epithelium and stratum intermedium (stratified cells that support the synthetic activity of the inner enamel epithelium) What follows is

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is rare, but is most likely to occur in the maxilla and anterior teeth. The cause is unknown; a number of causes have been postulated, including a disturbance in the neural crest cells, infection, radiation therapy, and a decrease in vascular supply (the most widely held hypothesis). Teeth affected

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in the cap stage. Groups of blood vessels form at the entrance of the dental papilla. The number of blood vessels reaches a maximum at the beginning of the crown stage, and the dental papilla eventually forms in the pulp of a tooth. Throughout life, the amount of pulpal tissue in a tooth decreases,

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In the maturation stage, the ameloblasts transport some of the substances used in enamel formation out of the enamel. Thus, the function of ameloblasts changes from enamel production, as occurs in the secretory stage, to transportation of substances. Most of the materials transported by ameloblasts

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After dentin formation begins, the cells of the IEE secrete an organic matrix against the dentin. This matrix immediately mineralizes and becomes the initial layer of the tooth's enamel. Outside the dentin are the newly formed ameloblasts in response to the formation of dentin, which are cells that

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Hard tissues, including enamel and dentin, develop during the next stage of tooth development. This stage is called the crown, or maturation stage, by some researchers. Important cellular changes occur at this time. In prior stages, all of the IEE cells were dividing to increase the overall size of

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substances, which results in an aggregation of these cells called the dental papilla. At this point, the tooth bud grows around the ectomesenchymal aggregation, taking on the appearance of a cap, and becomes the enamel (or dental) organ covering the dental papilla. A condensation of ectomesenchymal

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Fluoride ingestion has been noted to delay eruption of teeth for as much as a year or more from the accepted eruption dates since the initial 1940s fluoridation trials. Researchers theorize that the delay is a manifestation of fluoride's depressing impact on thyroid hormones. The delay in eruption

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The most widely held current theory is that while several forces might be involved in eruption, the periodontal ligaments provide the main impetus for the process. Theorists hypothesize that the periodontal ligaments promote eruption through the shrinking and cross-linking of their collagen fibers

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Cellular cementum develops after most of the tooth formation is complete and after the tooth occludes (in contact) with a tooth in the opposite arch. This type of cementum forms around the fiber bundles of the periodontal ligaments. The cementoblasts forming cellular cementum become trapped in the

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Secondary dentin is formed after root formation is finished and occurs at a much slower rate. It is not formed at a uniform rate along the tooth, but instead forms faster along sections closer to the crown of a tooth. This development continues throughout life and accounts for the smaller areas of

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Whereas mantle dentin forms from the preexisting ground substance of the dental papilla, primary dentin forms through a different process. Odontoblasts increase in size, eliminating the availability of any extracellular resources to contribute to an organic matrix for mineralization. Additionally,

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Odontoblasts, the dentin-forming cells, differentiate from cells of the dental papilla. They begin secreting an organic matrix around the area directly adjacent to the inner enamel epithelium, closest to the area of the future cusp of a tooth. The organic matrix contains collagen fibers with large

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separated from the ectomesenchyme by a basement membrane. Ectomesenchymal cells congregate deep to the bud, forming a cluster of cells, which is the initiation of the condensation of the ectomesenchyme. The remaining ectomesenchymal cells are arranged in a more or less haphazardly uniform fashion.

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A residue may form on newly erupted teeth of both dentitions that may leave the teeth extrinsically stained. This green-gray residue, Nasmyth membrane, consists of the fused tissue of the reduced enamel epithelium and oral epithelium, as well as the dental cuticle placed by the ameloblasts on the

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Tooth development is commonly divided into the following stages: the initiation stage, the bud stage, the cap stage, the bell stage, and finally maturation. The staging of tooth development is an attempt to categorize changes that take place along a continuum; frequently it is difficult to decide

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The origin of the formative cementoblasts is believed to be different for cellular cementum and acellular cementum. One of the major current hypotheses is that cells producing cellular cementum migrate from the adjacent area of bone, while cells producing acellular cementum arise from the dental

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The other dominant hypothesis, the "clone model", proposes that the epithelium programs a group of ectomesenchymal cells to generate teeth of particular shapes. This group of cells, called a clone, coaxes the dental lamina into tooth development, causing a tooth bud to form. Growth of the dental

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Along with the formation of the dental lamina, 10 round epithelial structures, each referred to as a bud, develop at the distal aspect of the dental lamina of each arch. These correspond to the 10 primary teeth of each dental arch, and they signify the bud stage of tooth development. Each bud is

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The crown of the tooth, which is influenced by the shape of the inner enamel epithelium, also takes shape during this stage. Throughout the mouth, all teeth undergo this same process; it is still uncertain why teeth form various crown shapes—for instance, incisors versus canines. There are two

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The connection between the gingiva and the tooth is called the dentogingival junction. This junction has three epithelial types: gingival, sulcular, and junctional epithelium. These three types form from a mass of epithelial cells known as the epithelial cuff between the tooth and the mouth.

1136:(HERS) has begun to deteriorate. The cementoblasts secrete fine collagen fibrils along the root surface at right angles before migrating away from the tooth. As the cementoblasts move, more collagen is deposited to lengthen and thicken the bundles of fibers. Noncollagenous proteins, such as 841:

cells called the dental sac or follicle surrounds the enamel organ and limits the dental papilla. Eventually, the enamel organ will produce enamel, the dental papilla will produce dentin and pulp, and the dental sac will produce all the supporting structures of a tooth, the periodontium.

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stage, occurs when only primary teeth are visible. Once the first permanent tooth erupts into the mouth, the teeth are in the mixed (or transitional) dentition. After the last primary tooth falls out of the mouth—a process known as exfoliation—the teeth are in the permanent dentition.

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The bell stage is known for the histodifferentiation and morphodifferentiation that takes place. The dental organ is bell-shaped during this stage, and the majority of its cells are called stellate reticulum because of their star-shaped appearance. The bell stage is divided into the

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Deficiencies of nutrients can have a wide range of effects on tooth development. In situations where calcium, phosphorus, and vitamin D are deficient, the hard structures of a tooth may be less mineralized. A lack of vitamin A can cause a reduction in the amount of enamel formation.

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Frequently, nerves and blood vessels run parallel to each other in the body, and the formation of both usually takes place simultaneously and in a similar fashion. However, this is not the case for nerves and blood vessels around the tooth, because of different rates of development.

1008:. This mineralized phase occurs very early around the 3rd or 4th month of pregnancy. This marks the first appearance of enamel in the body. Ameloblasts make enamel at the location of where the cusps of the teeth are located. Enamel grows outwards, away from the center of the tooth. 1066:. Thus, dentin formation proceeds toward the inside of the tooth. The odontoblast process causes the secretion of hydroxyapatite crystals and mineralization of the matrix. This area of mineralization is known as mantle dentin and is a layer usually about 150 μm thick. 1861:

Dilaceration is an abnormal bend found on a tooth, and is nearly always associated with trauma that moves the developing tooth bud. As a tooth is forming, a force can move the tooth from its original position, leaving the rest of the tooth to form at an abnormal angle.

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newly formed outer enamel surface. Nasmyth membrane then easily picks up stain from food debris and is hard to remove except by selective polishing. The child's supervising adults may need reassurance that it is only an extrinsic stain on a child's newly erupted teeth.

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start to near the tooth during the cap stage of tooth development and grow toward the dental follicle. Once there, the nerves develop around the tooth bud and enter the dental papilla when dentin formation has begun. Nerves never proliferate into the enamel organ.

1232:. In the case of alveolar bone, these osteoblast cells form from the dental follicle. Similar to the formation of primary cementum, collagen fibers are created on the surface nearest the tooth, and they remain there until attaching to periodontal ligaments. 1144:, are also secreted. Acellular cementum contains a secreted matrix of proteins and fibers. As mineralization takes place, the cementoblasts move away from the cementum, and the fibers left along the surface eventually join the forming periodontal ligaments. 1876:

or hypomineralization is a defect of the teeth caused by a disturbance in the formation of the organic enamel matrix, clinically visible as enamel defects. It may be caused by nutritional factors, some diseases (such as undiagnosed and untreated

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what stage should be assigned to a particular developing tooth. This determination is further complicated by the varying appearance of different histologic sections of the same developing tooth, which can appear to be different stages.

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of animals. Nonetheless, formation of the periodontal ligament begins with ligament fibroblasts from the dental follicle. These fibroblasts secrete collagen, which interacts with fibers on the surfaces of adjacent bone and cementum.

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Johnson, Lisa; Ganss, Bernhard; Wang, Andrew; Zirngibl, Ralph A.; Johnson, Danielle E.; Owen, Celeste; Bradley, Grace; Voronov, Irina (2017-10-01). "V-ATPases Containing a3 Subunit Play a Direct Role in Enamel Development in Mice".

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is present in the condensing ectomesenchymal cells of the dental papilla in the early cap stage tooth germ and plays multiple roles during morphogenetic and cytodifferentiation events in the tooth. There is a relationship between

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is a lack of some tooth development (not including third molars). It is one of the most common developmental abnormalities, affecting 3.5–8.0% of the population. Hypodontia is often associated with the absence of a

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Mitsiadis TA, Dicou E, Joffre A, Magloire H (January 1992). "Immunohistochemical localization of nerve growth factor (NGF) and NGF receptor (NGF-R) in the developing first molar tooth of the rat".

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in two stages: the secretory and maturation stages. Proteins and an organic matrix form a partially mineralized enamel in the secretory stage; the maturation stage completes enamel mineralization.

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adjacent to a tooth bud are forces known to cause dilaceration, as are primary (baby) teeth pushed upward by trauma into the gingiva where it moves the tooth bud of the permanent tooth.

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has been suggested as the reason for the apparent difference in decay among the youngest children. Fluoride ingestion during tooth development can lead to a permanent condition known as

1760:. Calcium and phosphorus are needed to properly form the hydroxyapatite crystals, and their levels in the blood are maintained by Vitamin D. Vitamin A is necessary for the formation of 144:

A significant amount of research has focused on determining the processes that initiate tooth development. It is widely accepted that there is a factor within the tissues of the first

1370:, usually at eight months, and lasts until the first permanent molars appear in the mouth, usually at six years. The primary teeth typically erupt in the following order: (1) central 1239:

destroy it, especially if force is placed on a tooth. As is the case when movement of teeth is attempted through orthodontics using bands, wires, or appliances, an area of bone under

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of the teeth form. The first mineralized hard tissues form at this location. At the same time, the IEE cells change in shape from cuboidal to columnar and become preameloblasts. The

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McDonagh Marian S, Whiting Penny F, Wilson Paul M, Sutton Alex J, Chestnutt Ivor, Cooper Jan, et al. Systematic review of water fluoridation. BMJ 2000; 321:855 (2000 York Review)

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below a tooth, which Sicher observed under a microscope on a histologic slide, was responsible for eruption. Later, the "ligament" Sicher observed was determined to be merely an

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part of the initial 'enamel organ', the center of which is made up of stellate reticulum cells that serve to protect the enamel organ. This is all encased by the OEE layer.

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The bud stage is characterized by the appearance of a tooth bud without a clear arrangement of cells. The stage technically begins once epithelial cells proliferate into the

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The permanent dentition begins when the last primary tooth is lost, usually at 11 to 12 years, and lasts for the rest of a person's life or until all of the teeth are lost (

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Christensen LR, Møllgård K, Kjaer I, Janas MS (September 1993). "Immunocytochemical demonstration of nerve growth factor receptor (NGF-R) in developing human fetal teeth".

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X-ray of teeth of a boy aged 5 years showing left lower primary molar and developing crowns of left lower permanent premolar (below primary molar) and permanent molars

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display enamel abnormalities, suggesting that the a3 gene mutation found in V-ATPases also plays a role in the development of hypomineralized and hypoplastic enamel.

1192:. Cementum is the only one of these that is a part of a tooth. Alveolar bone surrounds the roots of teeth to provide support and creates what is commonly called a " 3651:

Kanchana Waidyasekera et al. Why does fluorosed dentine show a higher susceptibility for caries: An ultra- morphological explanation. J Med Dent Sci 2010;57:17-23

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to be secreted in smaller amounts, which results in more tightly arranged, heterogeneous nucleation that is used for mineralization. Other materials (such as

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of the jaw. Typically, this occurs when the fetus is around 8 weeks old. The tooth bud itself is the group of cells at the periphery of the dental lamina.

256:, which are dentin-forming cells. Additionally, the junction between the dental papilla and inner enamel epithelium determines the crown shape of a tooth. 2538:

Cobourne MT, Hardcastle Z, Sharpe PT (November 2001). "Sonic hedgehog regulates epithelial proliferation and cell survival in the developing tooth germ".

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which means that the blood supply to the tooth decreases with age. The enamel organ is devoid of blood vessels because of its epithelial origin, and the

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continue the process of enamel formation; therefore, enamel formation moves outwards, adding new material to the outer surface of the developing tooth.

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As in other aspects of human growth and development, nutrition has an effect on the developing tooth. Essential nutrients for a healthy tooth include

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often causes dental enamel defects and can be the only manifestation of the disease, in absence of gastrointestinal symptoms or malabsorption signs.

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In the secretory stage, ameloblasts release enamel proteins that contribute to the enamel matrix, which is then partially mineralized by the enzyme

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Acellular cementum forms first. The cementoblasts differentiate from follicular cells, which can only reach the surface of the tooth's root once

3211: 1208:(PDL). Specific events leading to the formation of the periodontal ligament vary between deciduous (baby) and permanent teeth and among various 4066: 3578: 3698:

Ferraz EG, Campos Ede J, Sarmento VA, Silva LR (2012). "The oral manifestations of celiac disease: information for the pediatric dentist".

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The first signs of an arrangement of cells in the tooth bud occur in the cap stage. A small group of ectomesenchymal cells stops producing

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The following tables present the development timeline of human teeth. Times for the initial calcification of primary teeth are for weeks

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begin to form in the twentieth week. If teeth do not start to develop at or near these times, they will not develop at all, resulting in

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diameters (0.1–0.2 μm in diameter). The odontoblasts begin to move toward the center of the tooth, forming an extension called the

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Other events occur during the bell stage. The dental lamina disintegrates, leaving the developing teeth completely separated from the

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Although tooth eruption occurs at different times for different people, a general eruption timeline exists. Typically, humans have 20

3678: 1196:". Periodontal ligaments connect the alveolar bone to the cementum, and the gingiva is the surrounding tissue visible in the mouth. 225:(REE) after maturation of the enamel. The location where the outer enamel epithelium and inner enamel epithelium join is called the 1160:, cellular cementum is found only in the part of the root closest to the apex and in interradicular areas between multiple roots. 4166: 3906:

Suri L, Gagari E, Vastardis H (Oct 2004). "Delayed tooth eruption: pathogenesis, diagnosis, and treatment. A literature review".

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As root and cementum formation begin, bone is created in the adjacent area. Throughout the body, cells that form bone are called

241:. Keratin is also present in epithelial cells of tooth germ and a thin film of keratin is present on a recently erupted tooth ( 4083: 3601: 3764: 3458: 3393: 3359: 3303: 3272: 2816: 2766: 2323: 800:. It occurs in the sixth to seventh week of the embryonic life. The dental lamina connects the developing tooth bud to the 1133: 1090:

pulp found in older individuals. Tertiary dentin, also known as reparative dentin, forms in reaction to stimuli, such as

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Giuca MR, Cei G, Gigli F, Gandini P (2010). "Oral signs in the diagnosis of celiac disease: review of the literature".

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One of the earliest signs in the formation of a tooth that can be seen microscopically is the distinction between the

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Prenatal and postnatal ingestion of fluorides - A Progress Report. Reuben Feltman. D.D.S. Dental Digest. August 1956.

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Fluoridation: Errors & Omissions in Experimental Trials. Philip Sutton. 2nd ed. Melbourne University Press. 1960

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Townsend G, Richards L, Hughes T (May 2003). "Molar intercuspal dimensions: genetic input to phenotypic variation".

1854:. About 86% of these cases involve a single extra tooth in the mouth, most commonly found in the maxilla, where the 2581:

Nakatomi M, Morita I, Eto K, Ota MS (May 2006). "Sonic hedgehog signaling is important in tooth root development".

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Domingues MG, Jaeger MM, Araújo VC, Araújo NS (February 2000). "Expression of cytokeratins in human enamel organ".

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Thesleff I, Vaahtokari A, Kettunen P, Aberg T (1995). "Epithelial-mesenchymal signaling during tooth development".

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Histologic slide of developing hard tissues. Ameloblasts are forming enamel, while odontoblasts are forming dentin.

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Neville, B.W., Douglas Damm, Carl Allen, Jerry Bouquot. Oral & Maxillofacial Pathology. 2nd edition. 2002.

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The periodontium, which is the supporting structure of a tooth, consists of the cementum, periodontal ligaments,

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of these cells move closer to the stratum intermedium and away from the dental papilla as they become polarized.

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Radiograph of lower right (from left to right) third, second, and first molars in different stages of development

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Some systemic conditions may cause delayed tooth development, such as nutritional factors, endocrine disorders (

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with varying levels of severity, the result of fluoride's interference with the normal osteoblast development.

233:, which determines the root shape of the tooth. During tooth development there are strong similarities between 1235:

Like any other bone in the human body, alveolar bone is modified throughout life. Osteoblasts create bone and

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Illustrated Dental Embryology, Histology, and Anatomy, Bath-Balogh and Fehrenbach, Elsevier, 2011, page 58-59

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follicle. Nonetheless, it is known that cellular cementum is usually not found in teeth with one root. In

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Illustrated Dental Embryology, Histology, and Anatomy, Bath-Balogh and Fehrenbach, Elsevier, 2011, page 75

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The tooth germ is an aggregation of cells that eventually forms a tooth. These cells are derived from the

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Ross, Michael H., Gordon I. Kaye, and Wojciech Pawlina. Histology: a text and atlas. 4th edition. 2003.

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of the oral cavity; the two will not join again until the final eruption of the tooth into the mouth.

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are the cells responsible for cementogenesis. Two types of cementum form: cellular and acellular.

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is a complete lack of tooth development. It is rare, most often occurring in a condition called

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in this stage are proteins used to complete mineralization. The important proteins involved are

4423: 2452:"Nerve growth factor (NGF) supports tooth morphogenesis in mouse first branchial arch explants" 1447: 1419: 1411: 1240: 242: 2806: 1216:

This interaction leads to an attachment that develops as the tooth erupts into the mouth. The

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All stages (bud, cap, bell, crown), growth and morphogenesis of the teeth are regulated by a

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Toto PD, O'Malley JJ, Grandel ER (1967). "Similarities of keratinization and amelogenesis".

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may be required in such circumstances for an individual to achieve a straight set of teeth.

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is very common, occurring in 20–23% of the population, followed in prevalence by the

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can be so severe that last sections of enamel is missing, exposing the underlying dentin.

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Histologic slide of tooth in late bell stage. Note disintegration of dental lamina at top.

8: 4486: 4458: 3828:"Enamel hypoplasia and its role in identification of individuals: A review of literature" 2308: 1886: 1482: 1470: 1317: 1251: 1063: 335: 298: 214: 2709: 4453: 4017: 3990: 3854: 3827: 3549: 3524: 3500: 3475: 3115: 3090: 2958: 2674: 2606: 2563: 2481: 2395: 2364: 2283: 2213: 2174: 1997: 1929: 1858:

are located. Hyperdontia is believed to be associated with an excess of dental lamina.

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layer of the mouth for a significant time. This is regarded as the initiation stage.

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Cate, A.R. Ten. Oral Histology: development, structure, and function. 5th ed. 1998.

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Mhaske S, Yuwanati MB, Mhaske A, Ragavendra R, Kamath K, Saawarn S (Aug 18, 2013).

3950: 3915: 3849: 3839: 3544: 3536: 3495: 3487: 3110: 3102: 2962: 2934: 2723: 2713: 2658: 2590: 2547: 2512: 2463: 2430: 2391: 2348: 2275: 2240: 2197: 2158: 2123: 2084: 1945: 1837: 1773: 1407: 966: 938: 307: 288: 3661: 3397: 1163: 4316: 4261: 4087: 4070: 3682: 3605: 3582: 2843: 2793: 2551: 2421:[NGF Signals Supporting the Tooth Development are Mediated through p75]. 2279: 2201: 2162: 1984: 1925: 1910: 1878: 1804: 1800: 1780: 1355: 1351: 1276: 1247: 1193: 1055: 960:

The adjacent layer of cells in the dental papilla suddenly increases in size and

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Proceedings of the National Academy of Sciences of the United States of America

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form between the gingival epithelium and the tooth and are responsible for the

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2nd edition. Carol Stream, Illinois, Quintessence Publishing Co, Inc. 2001.

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Gustafson G, Sundström B (June 1975). "Enamel: morphological considerations".

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environment, all parts of the tooth must develop during appropriate stages of

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Cross-section of tooth at root. Note clear, acellular appearance of cementum.

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start to form between the sixth and eighth week of prenatal development, and

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Much about gingival formation is not fully understood, but it is known that

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10.1002/(SICI)1097-0177(199911)216:3<299::AID-DVDY8>3.0.CO;2-B

2403: 2360: 2209: 2170: 2135: 2100: 156: 4366: 4047: 1882: 1843: 1796: 1296: 1141: 1028:. By the end of this stage, the enamel has completed its mineralization. 909: 905: 904:

Other structures that may appear in a developing tooth in this stage are

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Kahn, Michael A. Basic Oral and Maxillofacial Pathology. Volume 1. 2001.

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from a tooth moving toward it has a high osteoclast level, resulting in

884: 4371: 4278:<Please add first missing authors to populate metadata.> (1995). 3878:"Severe Plane-Form Enamel Hypoplasia in a Dentition from Roman Britain" 3106: 2977:"Tertiary Dentine Frequencies in Extant Great Apes and Fossil Hominins" 2435: 2418: 2352: 1820: 1742: 1474: 1462: 1236: 1229: 1013: 894: 878: 801: 311: 303: 280: 276: 260:

cells within the dental papilla are responsible for formation of tooth

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Database on the expression of different genes in the developing tooth.

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Philbrick WM, Dreyer BE, Nakchbandi IA, Karaplis AC (September 1998).

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or 'enamel cuticle', structure of embryological origin is composed of

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Histologic slide of tooth in early bell stage. Note cell organization.

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Immediately after the eruption enamel is covered by a specific film:

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around the roots of teeth. Fibroblasts are involved developing the

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is the development of extraneous teeth. It occurs in 1–3% of

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Histologic slide of tooth. Note the tubular appearance of dentin.

229:. The growth of cervical loop cells into the deeper tissues forms 4081:"Table II. Effects of nutrient deficiencies on tooth development" 2691: 1855: 1828:, which is vulnerable to environmental forces like infection and 1761: 1749: 1746: 1738: 1722: 1371: 1358:. Tooth eruption has three stages. The first, known as deciduous 1209: 1185: 934: 775: 318: 234: 4218:

Summitt, James B., J. William Robbins, and Richard S. Schwartz.

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Dassule HR, Lewis P, Bei M, Maas R, McMahon AP (November 2000).

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Rosebury, Theodor (1934). "Presence of Iron in Enamel Keratin".

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medications. It is also associated with many syndromes, such as

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Rivera E, Assiri A, Guandalini S (Oct 2013). "Celiac disease".

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Table II. Effects of nutrient deficiencies on tooth development

3091:"Evolution and Development of Hertwig's Epithelial Root Sheath" 2113: 1937: 4309: 3988: 2450:

Amano O, Bringas P, Takahashi I, et al. (November 1999).

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Fundamentals of Operative Dentistry: A Contemporary Approach.

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Ross, Michael H.; Kaye, Gordon I.; Pawlina, Wojciech (2003).

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Ten Cate's Oral Histology, Nanci, Elsevier, 2013, pages 70-94

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Kanchan T, Machado M, Rao A, Krishan K, Garg AK (Apr 2015).

2804: 2627:. Gene expression in tooth by Pekka Nieminen. Archived from 2416: 2381: 2310:

Histology: a text and atlas: with cell and molecular biology

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because of decay, pain or impactions. The main reasons for

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of enamel and dentin do not need nutrients from the blood.

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which connect teeth to the alveolar bone through cementum.

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Ten Cate's Oral Histology, Nanci, Elsevier, 2013, page 135

2082: 3991:"Natal and neonatal teeth: an overview of the literature" 937:, stops during the crown stage at the location where the 4267: 3825: 2923: 2537: 4076: 4059: 2831:

University of Southern California School of Dentistry,

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University of Southern California School of Dentistry,

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Thesleff I, Vaahtokari A, Partanen AM (February 1995).

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University of Southern California School of Dentistry

3821: 3819: 3817: 3815: 2449: 1418:. Mandibular teeth erupt in the following order: (1) 4095:

Wheeler’s Dental Anatomy, Physiology, and Occlusion.

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Mitsiadis TA, Dicou E, Joffre A, Magloire H (2001).

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Animation of major stages in early tooth development

182:. The tooth germ is organized into three parts: the 3905: 3693: 3691: 3446: