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Hyperdontia
Hyperdontia is the condition of having supernumerary teeth, or teeth that appear in addition to the regular number of teeth (32 in the average adult). They can appear in any area of the dental arch and can affect any dental organ. The opposite of hyperdontia is hypodontia, where there is a congenital lack of teeth, which is a condition seen more commonly than hyperdontia.Pathology of the Hard Dental Tissues The scientific definition of hyperdontia is "any tooth or odontogenic structure that is formed from tooth germ in excess of usual number for any given region of the dental arch."R. S. Omer, R. P. Anthonappa, and N. M. King, "Determination of the optimum time for surgical removal of unerupted anterior supernumerary teeth," Pediatric Dentistry, vol. 32, no. 1, pp. 14–20, 2010. The additional teeth, which may be few or many, can occur on any place in the dental arch. Their arrangement may be symmetrical or non-symmetrical. Signs and symptoms The presence of a supernumerary to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Supernumerary Teeth
Hyperdontia is the condition of having supernumerary teeth, or teeth that appear in addition to the regular number of teeth (32 in the average adult). They can appear in any area of the dental arch and can affect any dental organ. The opposite of hyperdontia is hypodontia, where there is a congenital lack of teeth, which is a condition seen more commonly than hyperdontia.Pathology of the Hard Dental Tissues The scientific definition of hyperdontia is "any tooth or odontogenic structure that is formed from tooth germ in excess of usual number for any given region of the dental arch."R. S. Omer, R. P. Anthonappa, and N. M. King, "Determination of the optimum time for surgical removal of unerupted anterior supernumerary teeth," Pediatric Dentistry, vol. 32, no. 1, pp. 14–20, 2010. The additional teeth, which may be few or many, can occur on any place in the dental arch. Their arrangement may be symmetrical or non-symmetrical. Signs and symptoms The presence of a supernumerary to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Supernumerary Body Part
Supernumerary body parts are most commonly a congenital disorder involving the growth of an additional part of the body and a deviation from the body plan. Body parts may be easily visible or hidden away, such as internal organs. Many additional body parts form by the same process as conjoined twins: the zygote begins to split but fails to completely separate. This condition may also be a symptom of repeated occurrences of continuous inbreeding in a genetic line. Specific types of occurrence Specific types of additional body parts include: *Accessory breast – one or more additional breastsOnline Mendelian Inheritance in Man. Nipples, Supernumerary. Accessed 10 July 2006. *Accessory spleen – one or more additional spleens *Cervical rib – an additional rib *Diphallia – having two penes/penises *Hermaphroditism – having both male and female sex organs *Hyperdontia – additional teeth * Pelvic digit – a bony growth in the soft tissue of the pelvic region * Polycephaly ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Permanent Teeth
Permanent teeth or adult teeth are the second set of teeth formed in diphyodont mammals. In humans and old world simians, there are thirty-two permanent teeth, consisting of six maxillary and six mandibular molars, four maxillary and four mandibular premolars, two maxillary and two mandibular canines, four maxillary and four mandibular incisors. Timeline The first permanent tooth usually appears in the mouth at around six years of age, and the mouth will then be in a transition time with both primary (or deciduous dentition) teeth and permanent teeth during the mixed dentition period until the last primary tooth is lost or shed. The first of the permanent teeth to erupt are the permanent first molars, right behind the last 'milk' molars of the primary dentition. These first permanent molars are important for the correct development of a permanent dentition. Up to thirteen years of age, 28 of the 32 permanent teeth will appear. The full permanent dentition is completed muc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molar (tooth)
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 (mandib ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tricho-rhino-phalangeal Syndrome Type 1
Zinc finger transcription factor Trps1 is a protein that in humans is encoded by the ''TRPS1'' gene. This gene encodes a GATA-like transcription factor that represses GATA-regulated genes and binds to a dynein Dyneins are a family of cytoskeletal motor proteins that move along microtubules in cells. They convert the chemical energy stored in ATP to mechanical work. Dynein transports various cellular cargos, provides forces and displacements import ... light chain protein. Binding of the encoded protein to the dynein light chain protein affects binding to GATA consensus sequences and suppresses its transcriptional activity. Defects in this gene are a cause of tricho–rhino–phalangeal syndrome (TRPS) types I–III (also known as the Langer–Giedion syndrome). References Further reading * External links * Transcription factors {{gene-8-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nance–Horan Syndrome
Nance–Horan syndrome is a rare X-linked dominant syndrome characterized by congenital cataracts leading to profound vision loss, characteristic dysmorphic features, and dental anomalies. Microcornea, microphthalmia, and mild or moderate intellectual disability may accompany these features. Heterozygous females often manifest similarly but with less severe features than affected males. Presentation Dental features: * small teeth in males * pointed (screwdriver shaped or conical) incisors (sometimes called Hutchinson teeth) * incisors with an irregular incisal edge * canines: enlarged and globular; may be dome or bud shaped with trilobed edge * premolars and molars: small, round and globular; may have supernumary lobes (mulberry or lotus flower shape) * widely separated teeth ( diastemma) * hypoplastic enamel * dental agenesis * presence of mesiodents (median incisor behind normal upper incisors) * pulp chamber anomalies Facial features: * anteverted pinnae * long face * p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marfan Syndrome
Marfan syndrome (MFS) is a multi-systemic genetic disorder that affects the connective tissue. Those with the condition tend to be tall and thin, with long arms, legs, fingers, and toes. They also typically have exceptionally flexible joints and abnormally curved spines. The most serious complications involve the heart and aorta, with an increased risk of mitral valve prolapse and aortic aneurysm. The lungs, eyes, bones, and the covering of the spinal cord are also commonly affected. The severity of the symptoms is variable. MFS is caused by a mutation in '' FBN1'', one of the genes that makes fibrillin, which results in abnormal connective tissue. It is an autosomal dominant disorder. In about 75% of cases, it is inherited from a parent with the condition, while in about 25% it is a new mutation. Diagnosis is often based on the Ghent criteria. There is no known cure for MFS. Many of those with the disorder have a normal life expectancy with proper treatment. Managemen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Incontinentia Pigmenti
Incontinentia pigmenti (IP) is a rare X-linked dominant genetic disorder that affects the skin, hair, teeth, nails and central nervous system. It is named from its appearance under a microscope. The disease is characterized by skin abnormalities that begin in childhood, usually a blistering rash which heals, followed by the development of harder skin growths. The skin may develop grey or brown patches which fade with time. Other symptoms can include hair loss, dental abnormalities, eye abnormalities that can lead to vision loss and lined or pitted fingernails and toenails. Associated problems can include delayed development, intellectual disability, seizures and other neurological problems. Most males with the disease do not survive to childbirth. Incontinentia pigmenti is caused by a mutation in the ''IKBKG'' gene, which encodes the NEMO protein, which serves to protect cells against TNF-alpha-induced apoptosis. A lack of IKBKG therefore makes cells more prone to apoptosis. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orofaciodigital Syndrome 1
Orofaciodigital syndrome 1 (OFD1), also called Papillon-League and Psaume syndrome, is an X-linked congenital disorder characterized by malformations of the face, oral cavity, and digits with polycystic kidney disease and variable involvement of the central nervous system. Cause Orofaciodigital syndrome type 1 is caused by mutations in the OFD1 gene. OFD1 localizes to both centrosomes and basal bodies within the human genetic cellular structure. This suggests that this syndrome may fall into a broad category of ciliary diseases. The ciliary organelles are present in many cellular types throughout the human body. Cilia defects adversely affect numerous critical developmental signaling pathways essential to cellular development. Other types include: * * * * Relation to other rare genetic disorders Recent findings in genetic research have suggested that a large number of genetic disorders, both genetic syndromes and genetic diseases, that were not previously identi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hallermann–Streiff Syndrome
Hallermann–Streiff syndrome is a congenital disorder that affects growth, cranial development, hair-growth, and dental development. There are fewer than 200 people with the syndrome worldwide. One notable organization that is supporting people with Hallermann–Streiff syndrome is the Germany-based "Schattenkinder e.V". Presentation Patients with this syndrome are shorter than the average person and may not develop hair in many places, including in the facial, leg and pubic areas. Patients also have eye problems including reduced eye size, bilateral cataracts and glaucoma. The syndrome can be associated with sleep apnea. The physical characteristics of the syndrome can result in difficult intubation by medical professionals. Intelligence is usually normal. Cause The genetic cause of Hallermann–Streiff syndrome has not been conclusively determined. It is most likely due to a ''de novo'' mutation, and it may be associated with the ''GJA1'' gene. Diagnosis Diagnosis is bas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Goldenhar Syndrome
Goldenhar syndrome is a rare congenital defect characterized by incomplete development of the ear, nose, soft palate, lip and mandible on usually one side of the body. Common clinical manifestations include limbal dermoids, preauricular skin tags and strabismus. It is associated with anomalous development of the first branchial arch and second branchial arch. The term is sometimes used interchangeably with hemifacial microsomia, although this definition is usually reserved for cases without internal organ and vertebrae disruption. It affects between 1 in 3,500 and 1 in 5,600 live births, with a male-to-female ratio of 3:2. Signs and symptoms Chief markers of Goldenhar syndrome are incomplete development of the ear, nose, soft palate, lip, and mandible on usually one side of the body. Additionally, some patients will have growing issues with internal organs, especially heart, kidneys and lungs. Typically, the organ will either not be present on one side or will be underdevel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
