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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 p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benign Tumor
A benign tumor is a mass of cells (tumor) that does not invade neighboring tissue or metastasize (spread throughout the body). Compared to malignant (cancerous) tumors, benign tumors generally have a slower growth rate. Benign tumors have relatively well differentiated cells. They are often surrounded by an outer surface (fibrous sheath of connective tissue) or stay contained within the epithelium. Common examples of benign tumors include moles and uterine fibroids. Some forms of benign tumors may be harmful to health. Benign tumor growth causes a mass effect that can compress neighboring tissues. This can lead to nerve damage, blood flow reduction ( ischemia), tissue death (necrosis), or organ damage. The health effects of benign tumor growth may be more prominent if the tumor is contained within an enclosed space such as the cranium, respiratory tract, sinus, or bones. For example, unlike most benign tumors elsewhere in the body, benign brain tumors can be life-thr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 hard and soft tissues. As with normal tooth development, odontomas stop growing once mature which makes them benign. The average age of people found with an odontoma is 14. The condition is frequently associated with one or more unerupted teeth and is often detected through failure of teeth to erupt at the expected time. Though most cases are found impacted within the jaw there are instances where odontomas have erupted into the oral cavity. Types There are two main types: compound and complex. * A ''compound'' odontoma consists of the four separate dental tissues ( enamel, dentine, cementum and pulp) embedded in fibrous connective tissue and surrounded by a fibrous capsule. It may present a lobulated appearance where there is no defin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paresthesia
Paresthesia is an abnormal sensation of the skin (tingling, pricking, chilling, burning, numbness) with no apparent physical cause. Paresthesia may be transient or chronic, and may have any of dozens of possible underlying causes. Paresthesias are usually painless and can occur anywhere on the body, but most commonly occur in the arms and legs. The most familiar kind of paresthesia is the sensation known as "pins and needles" after having a limb "fall asleep". A less well-known and uncommon paresthesia is formication, the sensation of insects crawling on the skin. Causes Transient Paresthesias of the hands, feet, legs, and arms are common transient symptoms. The briefest electric shock type of paresthesia can be caused by tweaking the ulnar nerve near the elbow; this phenomenon is colloquially known as bumping one's "funny bone". Similar brief shocks can be experienced when any other nerve is tweaked (e.g. a pinched neck nerve may cause a brief shock-like paresthesia toward t ... [...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 t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 hard and soft tissues. As with normal tooth development, odontomas stop growing once mature which makes them benign. The average age of people found with an odontoma is 14. The condition is frequently associated with one or more unerupted teeth and is often detected through failure of teeth to erupt at the expected time. Though most cases are found impacted within the jaw there are instances where odontomas have erupted into the oral cavity. Types There are two main types: compound and complex. * A ''compound'' odontoma consists of the four separate dental tissues ( enamel, dentine, cementum and pulp) embedded in fibrous connective tissue and surrounded by a fibrous capsule. It may present a lobulated appearance where there is no defin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neoplasm
A neoplasm () is a type of abnormal and excessive growth of tissue. The process that occurs to form or produce a neoplasm is called neoplasia. The growth of a neoplasm is uncoordinated with that of the normal surrounding tissue, and persists in growing abnormally, even if the original trigger is removed. This abnormal growth usually forms a mass, when it may be called a tumor. ICD-10 classifies neoplasms into four main groups: benign neoplasms, in situ neoplasms, malignant neoplasms, and neoplasms of uncertain or unknown behavior. Malignant neoplasms are also simply known as cancers and are the focus of oncology. Prior to the abnormal growth of tissue, as neoplasia, cells often undergo an abnormal pattern of growth, such as metaplasia or dysplasia. However, metaplasia or dysplasia does not always progress to neoplasia and can occur in other conditions as well. The word is from Ancient Greek 'new' and 'formation, creation'. Types A neoplasm can be benign, potentia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Odontogenic Tumor
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] |
Hamartoma
A hamartoma is a mostly benign, local malformation of cells that resembles a neoplasm of local tissue but is usually due to an overgrowth of multiple aberrant cells, with a basis in a systemic genetic condition, rather than a growth descended from a single mutated cell ( monoclonality), as would typically define a benign neoplasm/tumor. Despite this, many hamartomas are found to have clonal chromosomal aberrations that are acquired through somatic mutations, and on this basis the term ''hamartoma'' is sometimes considered synonymous with neoplasm. Hamartomas are by definition benign, slow-growing or self-limiting, though the underlying condition may still predispose the individual towards malignancies. Hamartomas are usually caused by a genetic syndrome that affects the development cycle of all or at least multiple cells. Many of these conditions are classified as overgrowth syndromes or cancer syndromes. Hamartomas occur in many different parts of the body and are most oft ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enamel Organ
The enamel organ, also known as the dental organ, is a cellular aggregation seen in a developing tooth and it lies above the dental papilla. The enamel organ which is differentiated from the primitive oral epithelium lining the stomodeum.The enamel organ is responsible for the formation of enamel, initiation of dentine formation, establishment of the shape of a tooth's crown, and establishment of the dentoenamel junction. The enamel organ has four layers; the inner enamel epithelium, outer enamel epithelium, stratum intermedium, and the stellate reticulum. The dental papilla, the differentiated ectomesenchyme deep to the enamel organ, will produce dentin and the dental pulp. The surrounding ectomesenchyme tissue, the dental follicle, is the primitive cementum, periodontal ligament and alveolar bone beneath the tooth root. The site where the internal enamel epithelium and external enamel epithelium coalesce is the cervical root, important in proliferation of the dental root. ... [...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 t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dental Lamina
The dental lamina is a band of epithelial tissue seen in histologic sections of a developing tooth. The dental lamina is first evidence of tooth development and begins (in humans) at the sixth week in utero or three weeks after the rupture of the buccopharyngeal membrane. It is formed when cells of the oral ectoderm proliferate faster than cells of other areas. Best described as an in-growth of oral ectoderm, the dental lamina is frequently distinguished from the vestibular lamina, which develops concurrently. This dividing tissue is surrounded by and, some would argue, stimulated by ectomesenchymal growth. When it is present, the dental lamina connects the developing tooth bud to the epithelium of the oral cavity. Eventually, the dental lamina disintegrates into small clusters of epithelium and is resorbed. In situations when the clusters are not resorbed, (this remnant of the dental lamina is sometimes known as the glands of Serres) eruption cysts are formed over the developin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dental Papilla
In embryology and prenatal development, the dental papilla is a condensation of ectomesenchymal cells called odontoblasts, seen in histologic sections of a developing tooth. It lies below a cellular aggregation known as the enamel organ. The dental papilla appears after 8–10 weeks intra uteral life. The dental papilla gives rise to the dentin and pulp of a tooth. The enamel organ, dental papilla, and dental follicle together forms one unit, called the tooth germ. This is of importance because all the tissues of a tooth and its supporting structures form from these distinct cellular aggregations. Similar to dental follicle, the dental papilla has a very rich blood supply and provides nutrition to the enamel organ. Embryology Formation of dental papilla occurs in the Cap stage of Odontogenesis. The cap stage The cap stage is the second stage of tooth development and occurs during the ninth or tenth week of prenatal development. Unequal proliferation of the tooth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
