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Theories Of Craniofacial Growth
The development of craniofacial growth is a complicated phenomenon that has been the subject of much research for past 70 years. From the first theory in 1940s, many different ideas pertaining to how a face develops has intrigued the minds of researchers and clinicians alike. Key concepts Bone Remodeling is characterized by deposition and resorption of bone at different sites of a bone in the body, mostly for renewal and maintenance throughout life. This does not usually lead to change in size or shape of the bone. Bone Modeling is known as formation of new bone from either cartilage or by direct deposition, mostly during growth and development. This usually does lead to changes in size and shape over time. Growth Sites is a term proposed by Baume. Growth Sites serve as a location in the bone where the actual growth occurs. Growth sites are dependent on the growth centers for growth. Some examples include sutures of cranial vault, lateral cranial base and maxilla. Growth Center ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Development (biology)
Ontogeny (also ontogenesis) is the origination and development of an organism (both physical and psychological, e.g., moral development), usually from the time of fertilization of the egg to adult. The term can also be used to refer to the study of the entirety of an organism's lifespan. Ontogeny is the developmental history of an organism within its own lifetime, as distinct from phylogeny, which refers to the evolutionary history of a species. Another way to think of ontogeny is that it is the process of an organism going through all of the developmental stages over its lifetime. The developmental history includes all the developmental events that occur during the existence of an organism, beginning with the changes in the egg at the time of fertilization and events from the time of birth or hatching and afterward (i.e., growth, remolding of body shape, development of secondary sexual characteristics, etc.). While developmental (i.e., ontogenetic) processes can influence sub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hunterian Growth )
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Hunterian may refer to many things named after William Hunter (1718–1783): *Hunterian Collection *Hunterian Museum and Art Gallery * Hunterian Psalter The following are named after his brother, John Hunter (1728–1793): * Hunterian Society *Hunterian Museum at the Royal College of Surgeons of England * Hunterian Oration Other uses include: * Hunterian transliteration (named after William Wilson Hunter Sir William Wilson Hunter (15 July 18406 February 1900) was a Scottish historian, statistician, a compiler and a member of the Indian Civil Service. He is most known for ''The Imperial Gazetteer of India'' on which he started working in 1869, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Occlusion (dentistry)
Occlusion, in a dental context, means simply the contact between teeth. More technically, it is the relationship between the maxillary (upper) and mandibular (lower) teeth when they approach each other, as occurs during chewing or at rest. Static occlusion refers to contact between teeth when the jaw is closed and stationary, while dynamic occlusion refers to occlusal contacts made when the jaw is moving. The masticatory system also involves the periodontium, the TMJ (and other skeletal components) and the neuromusculature, therefore the tooth contacts should not be looked at in isolation, but in relation to the overall masticatory system. Anatomy of Masticatory System One cannot fully understand occlusion without an in depth understanding of the anatomy including that of the teeth, TMJ, musculature surrounding this and the skeletal components. The Dentition and Surrounding Structures The human dentition consists of 32 permanent teeth and these are distributed betwee ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alexandre Petrovic
Alexandre Petrovic (1925 – November 22, 2003) was a scientist who is known for formulating the Cybernetic Theory of Craniofacial Growth in 1977. Life Alex was born in Belgrade, Serbia. His father was a Serbian physician who at that time was doing his post-graduate training in surgery at University of Strasbourg School of Medicine. After birth, Alex's mother and him joined their father in Strasbourg where they lived for about 10 years before returning to Belgrade. Petrovic obtained his Medical degree in 1954, did his speciality in hematology in 1957 and his Doctorate in 1961. He did his Postdoc fellowship at McGill University, Canada in 1962. He was a professor of physiology and physiopathology at Louis Pasteur University Louis Pasteur University (''Université Louis-Pasteur''), also known as Strasbourg I or ULP was a large university in Strasbourg, Alsace, France. As of 15 January 2007, there were 18,847 students enrolled at the university, including around 3 ... . He ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intracranial Pressure
Intracranial pressure (ICP) is the pressure exerted by fluids such as cerebrospinal fluid (CSF) inside the skull and on the brain tissue. ICP is measured in millimeters of mercury ( mmHg) and at rest, is normally 7–15 mmHg for a supine adult. The body has various mechanisms by which it keeps the ICP stable, with CSF pressures varying by about 1 mmHg in normal adults through shifts in production and absorption of CSF. Changes in ICP are attributed to volume changes in one or more of the constituents contained in the cranium. CSF pressure has been shown to be influenced by abrupt changes in intrathoracic pressure during coughing (which is induced by contraction of the diaphragm and abdominal wall muscles, the latter of which also increases intra-abdominal pressure), the valsalva maneuver, and communication with the vasculature (venous and arterial systems). Intracranial hypertension (IH), also called increased ICP (IICP) or raised intracranial pressure (RICP), is elevation of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrocephalus
Hydrocephalus is a condition in which an accumulation of cerebrospinal fluid (CSF) occurs within the brain. This typically causes increased pressure inside the skull. Older people may have headaches, double vision, poor balance, urinary incontinence, personality changes, or mental impairment. In babies, it may be seen as a rapid increase in head size. Other symptoms may include vomiting, sleepiness, seizures, and downward pointing of the eyes. Hydrocephalus can occur due to birth defects or be acquired later in life. Associated birth defects include neural tube defects and those that result in aqueductal stenosis. Other causes include meningitis, brain tumors, traumatic brain injury, intraventricular hemorrhage, and subarachnoid hemorrhage. The four types of hydrocephalus are communicating, noncommunicating, ''ex vacuo'', and normal pressure. Diagnosis is typically made by physical examination and medical imaging. Hydrocephalus is typically treated by the surg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Soft Tissue
Soft tissue is all the tissue in the body that is not hardened by the processes of ossification or calcification such as bones and teeth. Soft tissue connects, surrounds or supports internal organs and bones, and includes muscle, tendons, ligaments, fat, fibrous tissue, lymph and blood vessels, fasciae, and synovial membranes. with :q=a_E_E_ \qquad Q=b_E_E_ quadratic forms of Green-Lagrange strains E_ and a_, b_ and c material constants. W is the strain energy function per volume unit, which is the mechanical strain energy for a given temperature. Isotropic simplification The Fung-model, simplified with isotropic hypothesis (same mechanical properties in all directions). This written in respect of the principal stretches (\lambda_i): :W = \frac\left (\lambda_1^2 + \lambda_2^2 + \lambda_3^2 - 3) + b\left( e^ -1 \right) \right/math> , where a, b and c are constants. Simplification for small and big stretches For small strains, the exponential term is very small, thus neg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Melvin Moss
Melvin Lionel Moss (1923 – June 26, 2006) was an American dentist known for creating the functional matrix hypothesis for growth and development. He was an anatomist and former dean of Columbia University College of Dental Medicine. Career Moss went to New York University and earned an undergraduate degree from there. He then attended Columbia Dental School and obtained his dental degree in 1946. Prior to dental school, he was part of the Dental Corps (United States Army). After his dental degree, Dr. Moss continued studying and received his PhD from Columbia in anatomy, specializing in physical Anthropology in 1954. Thereafter, he joined the school in 1955 as a faculty of anatomy. In 1968, Moss became the Dean of Columbia Dental School. He was also the professor emeritus of anatomy and oral biology in the Columbia University College of Physicians and Surgeons. Moss created the functional matrix hypothesis which is often used in the speciality of orthodontics Orthodontics is a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Functional Matrix Hypothesis
In the development of vertebrate animals, the functional matrix hypothesis is a phenomenological description of bone growth. It proposes that "the origin, development and maintenance of all skeletal units are secondary, compensatory and mechanically obligatory responses to temporally and operationally prior demands of related functional matrices." The fundamental basis for this hypothesis, laid out by Columbia anatomy professor Melvin Moss is that bones do not ''grow'' but ''are grown'', thus stressing the ontogenetic primacy of function over form. This is in contrast to the current conventional scientific wisdom that genetic, rather than epigenetic (non-genetic) factors, control such growth. The theory was introduced as a chapter in a dental textbook in 1962.''New York Times'Dr. Melvin Moss, 83, Theorist on How Bones of Face Grow, Is Dead June 29, 2006 See also * Wolff's law * Theories of Craniofacial Growth The development of craniofacial growth is a complicated phenomen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Synchondrosis and A synchondrosis (or primary cartilaginous joint) is a type of cartilaginous joint where hyaline cartilage completely joins together two bones. Synchondroses are different than symphyses (secondary cartilaginous joints) which are formed of fibrocartilage. Synchondroses are immovable joints and are thus referred to as synarthroses. Examples in the human body Permanent synchondroses * first sternocostal joint (where first rib meets the manubrium of the sternum) *petro-occipital synchondrosis Temporary synchondroses (fuse during development) *epiphyseal plates * apophyses * synchondroses in the developing hip bone composed of the ilium, ischium The ischium () form ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nasal Septum
The nasal septum () separates the left and right airways of the nasal cavity, dividing the two nostrils. It is depressed by the depressor septi nasi muscle. Structure The fleshy external end of the nasal septum is called the columella or columella nasi, and is made up of cartilage and soft tissue. The nasal septum contains bone and hyaline cartilage. It is normally about 2 mm thick. The nasal septum is composed of four structures: * Perpendicular plate of ethmoid bone * Vomer bone * Septal nasal cartilage * Maxillary bone (the crest) The lowest part of the septum is a narrow strip of bone that projects from the maxilla and the palatine bones, and is the length of the septum. This strip of bone is called the maxillary crest; it articulates in front with the septal nasal cartilage, and at the back with the vomer. The maxillary crest is described in the anatomy of the nasal septum as having a maxillary component and a palatine component. Development At an early peri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
