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Edentulous
Toothlessness or edentulism is the condition of having no teeth. In organisms that naturally have teeth, it is the result of tooth loss. Organisms that never possessed teeth can also be described as edentulous. Examples are the members of the former zoological classification order of '' Edentata'', which included anteaters and sloths, as they possess no anterior teeth and no or poorly developed posterior teeth. In naturally dentate species, edentulism is more than just the simple presence or absence of teeth. It is biochemically complex because the teeth, jaws, and oral mucosa are dynamic. Processes such as bone remodeling (loss and gain of bone tissue) in the jaws and inflammation of soft tissue in response to the oral microbiota are clinically important for edentulous people. For example, bone resorption in the jaw is frequently how the teeth were able to detach in the first place. The jaw in an edentulous area undergoes further resorption even after the teeth are gone; and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alveolar Ridge
The alveolar process () is the portion of bone containing the tooth sockets on the jaw bones (in humans, the maxilla and the mandible). The alveolar process is covered by gums within the mouth, terminating roughly along the line of the mandibular canal. Partially comprising compact bone, it is penetrated by many small openings for blood vessels and connective fibres. The bone is of clinical, phonetic and forensic significance. Terminology The term ''alveolar'' () ('hollow') refers to the cavities of the tooth sockets, known as dental alveoli. The alveolar process is also called the ''alveolar bone'' or ''alveolar ridge''. In phonetics, the term refers more specifically to the ridges on the inside of the mouth which can be felt with the tongue, either on roof of the mouth between the upper teeth and the hard palate or on the bottom of the mouth behind the lower teeth. The curved portion of the process is referred to as the alveolar arch. The alveolar bone proper, also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Head Of A Toothless Man With Bare, Sinewy Neck In Profile To Left MET DP823720
A head is the part of an organism which usually includes the ears, brain, forehead, cheeks, chin, eyes, nose, and mouth, each of which aid in various sensory functions such as sight, hearing, smell, and taste. Some very simple animals may not have a head, but many bilaterally symmetric forms do, regardless of size. Heads develop in animals by an evolutionary trend known as cephalization. In bilaterally symmetrical animals, nervous tissue concentrate at the anterior region, forming structures responsible for information processing. Through biological evolution, sense organs and feeding structures also concentrate into the anterior region; these collectively form the head. Human head The human head is an anatomical unit that consists of the skull, hyoid bone and cervical vertebrae. The skull consists of the brain case which encloses the cranial cavity, and the facial skeleton, which includes the mandible. There are eight bones in the brain case and fourteen in the facia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacteria
Bacteria (; : bacterium) are ubiquitous, mostly free-living organisms often consisting of one Cell (biology), biological cell. They constitute a large domain (biology), domain of Prokaryote, prokaryotic microorganisms. Typically a few micrometres in length, bacteria were among the first life forms to appear on Earth, and are present in most of its habitats. Bacteria inhabit the air, soil, water, Hot spring, acidic hot springs, radioactive waste, and the deep biosphere of Earth's crust. Bacteria play a vital role in many stages of the nutrient cycle by recycling nutrients and the nitrogen fixation, fixation of nitrogen from the Earth's atmosphere, atmosphere. The nutrient cycle includes the decomposition of cadaver, dead bodies; bacteria are responsible for the putrefaction stage in this process. In the biological communities surrounding hydrothermal vents and cold seeps, extremophile bacteria provide the nutrients needed to sustain life by converting dissolved compounds, suc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Commissures
A commissure () is the location at which two objects abut or are joined. The term is used especially in the fields of anatomy and biology. * The most common usage of the term refers to the brain's commissures, of which there are at least nine. Such a commissure is a bundle of commissural fibers as a tract that crosses the midline at its level of origin or entry (as opposed to a decussation of fibers that cross obliquely). The nine are the anterior commissure, posterior commissure, corpus callosum, commissure of fornix (hippocampal commissure), habenular commissure, ventral supraoptic decussation, Meynert's commissure, anterior hypothalamic commissure of Gasner, and the interthalamic adhesion. They consist of fibre tracts that connect the two cerebral hemispheres and span the longitudinal fissure. In the spinal cord, there are the anterior white commissure, and the gray commissure. ''Commissural neurons'' refer to neuronal cells that grow their axons across the midline of the ner ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maximum Intercuspidation
In mathematical analysis, the maximum and minimum of a function are, respectively, the greatest and least value taken by the function. Known generically as extremum, they may be defined either within a given range (the ''local'' or ''relative'' extrema) or on the entire domain (the ''global'' or ''absolute'' extrema) of a function. Pierre de Fermat was one of the first mathematicians to propose a general technique, adequality, for finding the maxima and minima of functions. As defined in set theory, the maximum and minimum of a set are the greatest and least elements in the set, respectively. Unbounded infinite sets, such as the set of real numbers, have no minimum or maximum. In statistics, the corresponding concept is the sample maximum and minimum. Definition A real-valued function ''f'' defined on a domain ''X'' has a global (or absolute) maximum point at ''x''∗, if for all ''x'' in ''X''. Similarly, the function has a global (or absolute) minimum point at ''x''∗, if ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quality Of Life
Quality of life (QOL) is defined by the World Health Organization as "an individual's perception of their position in life in the context of the culture and value systems in which they live and in relation to their goals, expectations, standards and concerns". Standard indicators of the quality of life include wealth, employment, the environment, physical and mental health, education, recreation and leisure time, social belonging, religious beliefs, safety, security and freedom. QOL has a wide range of contexts, including the fields of international development, healthcare, politics and employment. Health related QOL (HRQOL) is an evaluation of QOL and its relationship with health. Engaged theory One approach, called the engaged theory, outlined in the journal of ''Applied Research in the Quality of Life'', posits four domains in assessing quality of life: ecology, economics, politics and culture. In the domain of culture, for example, it includes the following subd ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mastication
Chewing or mastication is the process by which food is comminution, crushed and ground by the teeth. It is the first step in the process of digestion, allowing a greater surface area for digestive enzymes to break down the foods. During the mastication process, the food is positioned by the cheek and tongue between the teeth for grinding. The muscles of mastication move the jaws to bring the teeth into intermittent contact, repeatedly occlusion (dentistry), occluding and opening. As chewing continues, the food is made softer and warmer, and the enzymes in saliva begin to break down carbohydrates in the food. After chewing, the food (now called a Bolus (digestion), bolus) is swallowed. It enters the esophagus and via peristalsis continues on to the stomach, where the next step of digestion occurs. Increasing the number of chews per bite stimulates the production of digestive enzymes and peptides and has been shown to increase diet-induced thermogenesis (DIT) by activating the sympa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vertical Dimension Of Occlusion
Vertical dimension of occlusion, or VDO, also known as occlusal vertical dimension (OVD), is a term used in dentistry to indicate the superior-inferior relationship of the maxilla and the human mandible, mandible when the teeth are occlusion (dentistry), occluded in maximum intercuspation. A VDO is not only possessed by people who have teeth, however; for completely edentulous individuals who do not have any teeth with which to position themselves in maximum intercuspation, VDO can be measured based on subjective signs related to esthetics and phonetics. In terms of esthetics, an appropriately measured VDO will appear to a layman's eye as an ordinary configuration of the patient's nose, lips and chin. An excessive VDO will appear as though the patient has something stuffed into their mouth, and the patient may not even be able to close their lips. A telltale indication of an excessive VDO is a patient straining to close their lips around the wax rims during VDO determination. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Periodontal Pathology
Periodontal pathology, also termed gum diseases or periodontal diseases, are diseases involving the periodontium (the tooth supporting structures, i.e. the gums). The periodontium is composed of alveolar bone, periodontal ligament, cementum and gingiva. Classification An internationally agreed classification formulated at the World Workshop in Clinical Periodontics in 1989 divided periodontal diseases into 5 groups: adult periodontitis, early-onset periodontitis, periodontitis associated with systemic disease, necrotizing ulcerative periodontitis and refractory periodontitis. In 1993 at the 1st European Workshop in Periodontology the earlier classification was simplified and the categories periodontitis associated with systemic disease and refractory periodontitis were dropped. Both of these classification systems were widely used in clinical and research settings. However, they failed to address a gingival disease component, had overlapping categories with unclear classification ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stomatitis
Stomatitis is inflammation of the mouth and lips. It refers to any inflammatory process affecting the mucous membranes of the mouth and lips, with or without oral ulceration. In its widest meaning, stomatitis can have a multitude of different causes and appearances. Common causes include infections, nutritional deficiencies, allergic reactions, radiotherapy, and many others. When inflammation of the gums and the mouth generally presents itself, sometimes the term ''gingivostomatitis'' is used, though this is also sometimes used as a synonym for herpetic gingivostomatitis. The term is derived . Causes Nutritional deficiency Malnutrition (improper dietary intake) or malabsorption (poor absorption of nutrients into the body) can lead to nutritional deficiency states, several of which can lead to stomatitis. For example, deficiencies of iron, vitamin B2 (riboflavin), vitamin B3 (niacin), vitamin B6 (pyridoxine), vitamin B9 (folic acid) or vitamin B12 (cobalamine) may all manif ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dental Caries
Tooth decay, also known as caries,The word 'caries' is a mass noun, and is not a plural of 'carie'.'' is the breakdown of teeth due to acids produced by bacteria. The resulting cavities may be a number of different colors, from yellow to black. Symptoms may include pain and difficulty eating. Complications may include periodontal disease, inflammation of the tissue around the tooth, tooth loss and infection or dental abscess, abscess formation. Tooth regeneration is an ongoing Stem-cell therapy, stem cell–based field of study that aims to find methods to reverse the effects of decay; current methods are based on easing symptoms. The cause of cavities is acid from bacteria dissolving the hard tissues of the teeth (Tooth enamel, enamel, dentin and cementum). The acid is produced by the bacteria when they break down food debris or sugar on the tooth surface. Simple sugars in food are these bacteria's primary energy source and thus a diet high in simple sugar is a risk factor. I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gingivitis
Gingivitis is a non-destructive disease that causes inflammation of the gums; ulitis is an alternative term. The most common form of gingivitis, and the most common form of periodontal disease overall, is in response to bacterial biofilms (also called plaque) that are attached to tooth surfaces, termed ''plaque-induced gingivitis''. Most forms of gingivitis are plaque-induced. While some cases of gingivitis never progress to periodontitis, periodontitis is always preceded by gingivitis. Gingivitis is reversible with good oral hygiene; however, without treatment, gingivitis can progress to periodontitis, in which the inflammation of the gums results in tissue destruction and bone resorption around the teeth. Periodontitis can ultimately lead to tooth loss. Signs and symptoms The symptoms of gingivitis are somewhat non-specific and manifest in the gum tissue as the classic signs of inflammation: *Swollen gums *Bright red gums *Gums that are tender or painful to the touch *B ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
