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Apert Syndrome, virtually synonymous with Acrocephalosyndactyly, is a branchial arch syndrome, characterized by a number of clinical features, resulting from a developmental anomaly. Specifically, this syndrome affects the first branchial (or pharyngeal) arch, which is the precursor of the maxilla and mandible. Since the branchial arches are important developmental features in a growing embryo, disturbances in its development create lasting and widespread effects. The maxillae are the largest bones of the face, except for the mandible, and form, by their union, the whole of the upper jaw. ...
This article is about the human bone. ...
Embryos (and one tadpole) of the wrinkled frog (Rana rugosa). ...
Overview
In 1906, Eugène Apert, a French physician, first described nine people with a similar disorder. Since he was the first to do so, his name is associated with the syndrome. 1906 was a common year starting on Monday (see link for calendar). ...
Breaking down the name of this disorder, “acro” means “peak” in Greek and refers to the “peaked” hands of some people with this syndrome. Syndactyly refers to the webbing of fingers and toes.
What occurs in embryology is that hands and feet are supposed to have some selective cells die (known as selective cell death or apoptosis to separate the fingers and toes. In the case of acrocephalosyndactyly, selective cell death does not occur, and fusion of skin, and sometimes bone, between the fingers and toes occur. Embryology is the subdivision of developmental biology that studies embryos and their development. ...
In biology, apoptosis (from the Greek words apo = from and ptosis = falling, pronounced ap-a-tow-sis[1]) is one of the main types of programmed cell death (PCD). ...
As in Crouzon Syndrome, the bones of the skull are affected as well. Cranial synostosis results from the infant’s skull and facial bones fusing early while in development--- disabling the ability for normal bone growth. Fusion of different sutures lead to different patterns of growth of the skull. Examples include: trigonocephaly (fusion of the metopic suture), brachycephaly (fusion of the metopic suture), dolichocephaly (fusion of the sagittal suture), plagiocephaly (fusion of coronal and lambdoidal sutures), oxycephaly (fusion of most sutures). Crouzon Syndrome is a type of genetic disorder known as a branchial arch syndrome. ...
Cephalic disorders are congenital conditions that stem from damage to, or abnormal development of, the budding nervous system. ...
Cephalic disorders are congenital conditions that stem from damage to, or abnormal development of, the budding nervous system. ...
Cephalic disorders are congenital conditions that stem from damage to, or abnormal development of, the budding nervous system. ...
Cephalic disorders are congenital conditions that stem from damage to, or abnormal development of, the budding nervous system. ...
Causes There is some support that acrocephalosyndactyly occurs in an autosomal dominant mode, but the basic defect is still unknown. Evidence for this is that males and females are affected equally. An autosomal dominant gene is an abnormal gene on one of the autosomal (non-sex determining) chromosomes. ...
Nonetheless, almost all cases are sporadic, signifying that most are attributable to fresh mutations or an environmental insult to the genetic code. In 1995, A.O.M Wilkie, along with other researchers, published a paper showing evidence of a relationship between acrocephalosyndactyly and a gene, called Fibroblast Growth Factor Receptor 2, on chromosome 10. This stylistic schematic diagram shows a gene in relation to the double helix structure of DNA and to a chromosome (right). ...
Figure 1: Chromosome. ...
There is also some evidence that the age of the father is related to this syndrome. This stands in stark contrast to Down Syndrome, where the age of the mother is positively correlated with the risk of having a child with the syndrome. It is speculated that older fathers are more likely to have mutations in the chromosomes of their sperm, but a correlation to this disorder has not been established through scientific research.
Symptoms The cranial malformations are the most apparent effects of acrocephalosyndactyly. Cranial synostosis occurs, as explained above, with Brachiocephaly being the common pattern of growth. Additionally, a common characteristic is a high, prominent forehead and a flat posterior skull. Due to the premature closing of sutures of the skull, increased cranial pressure develops which sometimes leads to mental deficiency. Nonetheless, this is not always the case since some of these people possess normal intelligence. Furthermore, a flat or concave face may develop because of a deficient growth in the mid-facial bones, leading to a condition known as pseudomandibular prognathism. Other features of acrocephalosyndactyly may be shallow bony orbits and broadly spaced eyes.
Low-set ears is also a typical characteristic, as is with all of these disorders that are called branchial arch syndromes. The reason for this is that in fetal life all ears are much lower than what we are accustomed to seeing. During normal development, the ears "travel" upward on the head but, in these cases, the ears do not follow this normal pattern of development since these syndromes have the greatest effects on the head.
The major attribute of this syndrome is syndactyly of the hands and feet. Commonly there is fusion of fingers or toes with usually an equal amount on both sides. It is usual for the middle 3 fingers to be fused together. This appearance is the characteristic for which acrocephalosyndactyly is named. The thumb and big toe may be broad and malformed. This disorder is progressive with age as the joints continue to appear present but are immovable.
Treatments Surgery is needed to prevent the closing of sutures in the skull from damaging brain development. Combined orthodontic and orthognathic surgery can help to relieve some of the facial deformities, such as the flat or concave face. In particular, the LeFort III, a surgical procedure, can be used to detach the midface from the rest of the skull to reposition it appropriately. Additionally, aggressive surgery is needed to separate as many fingers and toes as possible in life. As of yet, there is no way to separate bones of the hands and fingers once the fusion has taken place. Orthodontics or orthodontia is the specialty of dentistry that is concerned with the study and treatment of malocclusions, which may be a result of tooth irregularity, disproportionate jaw relationships, or both. ...
Dental significance For dentists, this disorder is very important to understand since most of the physical abnormalities are presented in the head, and particularly the oral cavity. Common relevant features of acrocephalosyndactyly are a high-arched palate, pseudomandibular prognathism (appearing as mandibular prognathism), a short width of the palate, and crowding of the teeth. X-rays can reveal if a person has cavities Dentistry is the practical application of knowledge of dental science (the science of placement, arrangement, function of teeth) to human beings. ...
The mouth, also known as the buccal cavity or the oral cavity, is the opening through which an animal or human takes in food. ...
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