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Interrod Enamel
Interrod enamel is histologically identified on microscopic views of tooth enamel. Because interrod enamel is located around enamel rods, the areas of interrod enamel enhances the "keyhole" appearance of enamel rods by acting as its border. The location where the two areas of enamel meet is known as the rod sheath. All tooth enamel, including interrod enamel and enamel rods, is made by ameloblast Ameloblasts are cells present only during tooth development that deposit tooth enamel, which is the hard outermost layer of the tooth forming the surface of the crown. Structure Each ameloblast is a columnar cell approximately 4 micrometers in ...s. However, interrod enamel is formed slightly sooner than enamel rods. Interrod enamel has the same composition as enamel rods. A distinction is made between the two because they differ in the direction of their crystalline patterns. References *Cate, A.R. Ten. Oral Histology: development, structure, and function. 5th ed. 1998. . Pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Histology
Histology, also known as microscopic anatomy or microanatomy, is the branch of biology which studies the microscopic anatomy of biological tissues. Histology is the microscopic counterpart to gross anatomy, which looks at larger structures visible without a microscope. Although one may divide microscopic anatomy into ''organology'', the study of organs, ''histology'', the study of tissues, and ''cytology'', the study of cells, modern usage places all of these topics under the field of histology. In medicine, histopathology is the branch of histology that includes the microscopic identification and study of diseased tissue. In the field of paleontology, the term paleohistology refers to the histology of fossil organisms. Biological tissues Animal tissue classification There are four basic types of animal tissues: muscle tissue, nervous tissue, connective tissue, and epithelial tissue. All animal tissues are considered to be subtypes of these four principal tissue types ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tooth Enamel
Tooth enamel is one of the four major Tissue (biology), 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 (tooth), crown. The other major tissues are dentin, cementum, and Pulp (tooth), 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 o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enamel Rod
An enamel prism, or enamel rod, is the basic unit of tooth enamel. Measuring 3-6 μm in diameter, enamel prism are tightly packed hydroxyapatite crystals structures. The hydroxyapatite crystals are hexagonal in shape, providing rigidity to the prism and strengthening the enamel. In cross-section, it is best compared to a complex “keyhole” or a “fish-like” shape. The head, which is called the prism core, is oriented toward the tooth’s crown; The tail, which is called the prism sheath, is oriented toward the tooth cervical margin /sup>. The prism core has tightly packed hydroxyapatite crystals. On the other hand, the prism sheath has its crystals less tightly packed and has more space for organic components. These prism structures can usually be visualised within ground sections and/or with the use of a scanning electron microscope on enamel that has been acid etched .html" ;"title="/sup>">/sup>. The number of enamel prisms range approximately from 5 million to 12 mi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rod Sheath
Rod sheath is an area identified in histologic sections of a tooth. It is found where enamel rods, the functional unit of enamel, meet interrod enamel. The crystals of both types of enamel meet at sharp angles and form the appearance of a space called the rod sheath. As a result of this space, the rod sheath consists of more protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, res ... (as opposed to minerals) than other areas of enamel. For this reason, the rod sheath is characterized as being hypomineralized in comparison to the rest of the highly mineralized enamel. Additionally, the rod sheath is attributed with giving tooth enamel a "fish-scale" appearance under a microscope when the enamel has been demineralized or acid-etched. The rod sheath is Inorganic matrix tying the en ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ameloblast
Ameloblasts are cells present only during tooth development that deposit tooth enamel, which is the hard outermost layer of the tooth forming the surface of the crown. Structure Each ameloblast is a columnar cell approximately 4 micrometers in diameter, 40 micrometers in length and is hexagonal in cross section. The secretory end of the ameloblast ends in a six-sided pyramid-like projection known as the Tomes' process. The angulation of the Tomes' process is significant in the orientation of enamel rods, the basic unit of tooth enamel. Distal terminal bars are junctional complexes that separate the Tomes' processes from ameloblast proper. Development Ameloblasts are derived from oral epithelium tissue of ectodermal origin. Their differentiation from preameloblasts (whose origin is from inner enamel epithelium) is a result of signaling from the ectomesenchymal cells of the dental papilla. Initially the preameloblasts will differentiate into presecretory ameloblasts and then into s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parts Of Tooth
Part, parts or PART may refer to: People *Armi Pärt (born 1991), Estonian handballer *Arvo Pärt (born 1935), Estonian classical composer *Brian Part (born 1962), American child actor *Dealtry Charles Part (1882–1961), sheriff (1926–1927) and Lord Lieutenant (1943–1957) of Bedfordshire, racehorse owner *Dionysius Part (also known as ''Denys Part''; died 1475), Roman Catholic prelate, Auxiliary Bishop of Mainz (1474–1475) *John Part (born 1966), Canadian darts player *Michael Pärt (born 1977), Estonian music producer and film composer *Veronika Part (born 1978), Russian ballet dancer *Pärt Uusberg (born 1986), Estonian composer and conductor * Parts (surname) Arts, entertainment, and media *Part (music), a single strand or melody or harmony of music within a larger ensemble or a polyphonic musical composition * ''Parts'' (book), a 1997 children's book by Tedd Arnold Transportation * Pottstown Area Rapid Transit (PART), Pennsylvania, U.S. *Putnam Area Rapid Transit (PART ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
