|
Odontogenic Tumours
An odontogenic tumor is a neoplasm of the cells or tissues that initiate odontogenic processes. Examples include: * Adenomatoid odontogenic tumor * Ameloblastic fibroma * Ameloblastic fibro-odontoma * Ameloblastoma, a type of odontogenic tumor involving ameloblasts * Ameloblastic fibrosarcoma * Calcifying cystic odontogenic tumor * Calcifying epithelial odontogenic tumor * Cementoblastoma * Cementoma *Odontogenic keratocyst * Odontogenic carcinoma * Odontogenic myxoma * Odontoma An odontoma, also known as an odontome, is a benign tumour linked to tooth development. Specifically, it is a dental hamartoma, meaning that it is composed of normal dental tissue that has grown in an irregular way. It includes both odontogenic h ... * Squamous odontogenic tumour References External links Anatomical pathology *Main {{neoplasm-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Odontogenic
Tooth development or odontogenesis is the complex process by which teeth form from embryonic cells, grow, and erupt into the mouth. For human teeth to have a healthy oral environment, all parts of the tooth must develop during appropriate stages of fetal development. Primary (baby) teeth start to form between the sixth and eighth week of prenatal development, and permanent teeth begin to form in the twentieth week.Ten Cate's Oral Histology, Nanci, Elsevier, 2013, pages 70-94 If teeth do not start to develop at or near these times, they will not develop at all, resulting in hypodontia or anodontia. 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 pharyngeal arch that is necessary for the development of teeth. Overview The tooth germ is an aggregation of cells that eventually forms a tooth.University of Texas Medical Branch. These cells are der ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adenomatoid Odontogenic Tumor
The adenomatoid odontogenic tumor is an odontogenic tumor arising from the enamel organ or dental lamina. Signs and symptoms Two thirds of cases are located in the anterior maxilla, and one third are present in the anterior mandible. Two thirds of the cases are associated with an impacted tooth (usually being the canine). Diagnosis On radiographs, the adenomatoid odontogenic tumor presents as a radiolucency (dark area) around an unerupted tooth extending past the cementoenamel junction. It should be differentially diagnosed from a dentigerous cyst and the main difference is that the radiolucency in case of AOT extends apically beyond the cementoenamel junction. Radiographs will exhibit faint flecks of radiopacities surrounded by a radiolucent zone. It is sometimes misdiagnosed as a cyst A cyst is a closed sac, having a distinct envelope and cell division, division compared with the nearby Biological tissue, tissue. Hence, it is a cluster of Cell (biology), cells that have g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ameloblastic Fibroma
An ameloblastic fibroma is a fibroma of the ameloblastic tissue, that is, an odontogenic tumor arising from the enamel organ or dental lamina. It may be either truly neoplastic or merely hamartomatous (an odontoma). In neoplastic cases, it may be labeled an ameloblastic fibrosarcoma in accord with the terminological distinction that reserves the word ''fibroma'' for benign tumors and assigns the word ''fibrosarcoma'' to malignant ones. It is more common in the first and second decades of life, when odontogenesis is ongoing, than in later decades. In 50% of cases an unerupted tooth is involved. Histopathology alone is usually not enough to differentiate neoplastic cases from hamartomatous ones, because the histology is very similar. Other clinical and radiographic clues are used to narrow the diagnosis. Classification An ameloblastic fibroma is classified by The World Health Organisation as a benign mixed odontogenic tumour (1). It develops from the dental tissues that grow into te ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ameloblastic Fibro-odontoma
The ameloblastic fibro-odontoma (AFO) is essentially a benign tumor with the features characteristic of ameloblastic fibroma along with enamel and dentin (hard tissues). Though it is generally regarded as benign, there have been cases of its malignant transformation into ameloblastic fibrosarcoma and odontogenic sarcoma. Cahn LR and Blum T, believed in “maturation theory”, which suggested that AFO was an intermediate stage and eventually developed during the period of tooth formation to a complex odontoma thus, being a hamartoma. World Health Organization (WHO) defines AFO as a neoplasm consisting of odontogenic ectomesenchyme resembling the dental papilla, epithelial strands and nest resembling dental lamina and enamel organ conjunction with the presence of dentine and enamel. There is a consensus that AFO should be grouped under Odontomas. This is because once the hard tissues start forming it will eventually lead to formation of Odontomas. The Recent WHO classification ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ameloblastoma
Ameloblastoma is a rare, benign or cancerous tumor of odontogenic epithelium (ameloblasts, or outside portion, of the teeth during development) much more commonly appearing in the lower jaw than the upper jaw. It was recognized in 1827 by Cusack. This type of odontogenic neoplasm was designated as an ''adamantinoma'' in 1885 by the French physician Louis-Charles Malassez. It was finally renamed to the modern name ''ameloblastoma'' in 1930 by Ivey and Churchill. While these tumors are rarely malignant or metastatic (that is, they rarely spread to other parts of the body), and progress slowly, the resulting lesions can cause severe abnormalities of the face and jaw leading to severe disfiguration. Additionally, as abnormal cell growth easily infiltrates and destroys surrounding bony tissues, wide surgical excision is required to treat this disorder. If an aggressive tumor is left untreated, it can obstruct the nasal and oral airways making it impossible to breathe without oropharyng ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ameloblasts
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] |
Calcifying Odontogenic Cyst
Calcifying odotogenic cyst (COC) is a rare developmental lesion that comes from odontogenic epithelium. It is also known as a calcifying cystic odontogenic tumor, which is a proliferation of odontogenic epithelium and scattered nest of ghost cells and calcifications that may form the lining of a cyst, or present as a solid mass. It can appear in any location in the oral cavity, but more commonly affects the anterior (front) mandible and maxilla. It is most common in individuals in their 20s to 30s, but can be seen at almost any age, regardless of gender. On dental radiographs, the calcifying odontogenic cyst appears as a unilocular (one circle) radiolucency (dark area). In one-third of cases, an impacted tooth is involved. Histologically, cells that are described as " ghost cells", enlarged eosinophilic epithelial cells without nuclei, are present within the epithelial lining and may undergo calcification. Signs and symptoms Most calcifying odontogenic cysts appear asymptomat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcifying Epithelial Odontogenic Tumor
The calcifying epithelial odontogenic tumor (CEOT), also known as a Pindborg tumor, is an odontogenic tumor first recognized by the Danish pathologist Jens Jørgen Pindborg in 1955. It was previously described as an ''adenoid adamantoblastoma'', ''unusual ameloblastoma'' and a ''cystic odontoma''. Like other odontogenic neoplasms, it is thought to arise from the epithelial element of the enamel origin. It is a typically benign and slow growing, but invasive neoplasm. Types Intraosseous tumors (tumors within the bone) are more common (94%) than extraosseous tumors (6%). It is more common in the posterior mandible of adults, typically in the fourth to fifth decades. There may be a painless swelling, and it is often concurrent with an impacted tooth. On radiographs, it appears as a radiolucency (dark area) and is known for sometimes having small radiopacities (white areas) within it. In those instances, it is described as having a "driven-snow" appearance. Microscopically, there ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cementoblastoma
Cementoblastoma, or benign cementoblastoma, is a relatively rare benign neoplasm of the cementum of the teeth. It is derived from ectomesenchyme of odontogenic origin. Cementoblastomas represent less than 0.69–8% of all odontogemic tumors. Signs and symptoms Cementoblastoma usually occurs in people under the age of 25, particularly males. It usually involves the permanent mandibular molars or premolars. The involved tooth usually has a vital pulp. It is attached to the tooth root and may cause its resorption, may involve the pulp canal, grows slowly, tends to expand the overlying cortical plates, and, except for the enlargement produced, is usually asymptomatic. This involves the buccal and lingual aspects of the alveolar ridges. But may be associated with diffuse pain and tooth mobility, but the tooth is still vital. Since a cementoblastoma is a benign neoplasm, it grossly forms a mass of cementum-like tissue as an irregular or round mass attached to the roots of a tooth, usua ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cementoma
Cementoma is an odontogenic tumor of cementum. It is usually observed as a benign spherical mass of hard tissue fused to the root of a tooth. It is found most commonly in the mandible in the region of the lower molar teeth, occurring between the ages of 8 to 30 in both sexes with equal frequency . It causes distortion of surrounding areas but is usually a painless growth, at least initially. Considerable thickening of the cementum can often be observed. A periapical form is also recognized. Cementoma is not exclusive to the mandible as it can infrequently occur in the maxilla and other parts of the body such as the long bones. Signs & Symptoms Cementoma is characterized by a significant amount of thickening of the cementum around the roots of the teeth. The main teeth involved can include deciduous and permanent teeth, impacted molars and premolars. The growth is typically benign and painless. Although symptoms may not be noticeable, a dull pain and dentin hypersensitivity can o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Odontogenic Keratocyst
An odontogenic keratocyst is a rare and benign but locally aggressive developmental cyst. It most often affects the posterior mandible and most commonly presents in the third decade of life. Odontogenic keratocysts make up around 19% of jaw cysts. In the WHO/IARC classification of head and neck pathology, this clinical entity had been known for years as the odontogenic keratocyst; it was reclassified as keratocystic odontogenic tumour (KCOT) from 2005 to 2017. In 2017 it reverted to the earlier name, as the new WHO/IARC classification reclassified OKC back into the cystic category. Under The WHO/IARC classification, Odontogenic Keratocyst underwent the reclassification as it is no longer considered a neoplasm due to a lack of quality evidence regarding this hypothesis, especially with respect to clonality. Within the Head and Neck pathology community there is still controversy surrounding the reclassification, with some pathologists still considering Odontogenic Keratocyst as a neo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Odontogenic Myxoma
The odontogenic myxoma is an uncommon benign odontogenic tumor arising from embryonic connective tissue associated with tooth formation.Sapp, J. Philip., Lewis R. Eversole, and George P. Wysocki. Contemporary Oral and Maxillofacial Pathology. 2nd ed. St. Louis, MO: Mosby, 2002. 152-53. As a myxoma, this tumor consists mainly of spindle shaped cells and scattered collagen fibers distributed through a loose, mucoid material.Cawson, R. A., and E. W. Odell. Cawson's Essentials of Oral Pathology and Oral Medicine. 8th ed. Edinburgh: Churchill Livingstone, 2008. 145-46. Signs and symptoms Odontogenic myxomas have been found in patients ranging in age between 2 and 50 years, however, they are most commonly diagnosed in young adults (specifically between 25 and 35 years of age).Wood, Norman K., Paul W. Goaz, and Norman K. Wood. Differential Diagnosis of Oral and Maxillofacial Lesions. 5th ed. St. Louis: Mosby, 1997. 342-43.McDonald, Ralph E., David R. Avery, and Jeffrey A. Dean. Dentistry ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
