In mammals teeth develop as distinct organs. Some organs such as hair and certain glands share similarities with tooth organogenesis in their morphological and molecular features of development, but not their regenerative abilities. Dentition, by definition, refers to characteristics of a set of teeth including type, arrangement, shape, and number. During their evolutionary course, mammals have developed a reduced ability for tooth regeneration, but on the other hand mammalian teeth have developed many variations in size and shape. Mammalian dentition can be divided into four tooth types; incisor, canine, pre-molar (bicuspid), and molar teeth. Molar teeth specifically are the most diversely shaped teeth of the four types.
Although teeth can develop from either endoderm or mesoderm, in mammals neural crest and ectodermal tissues produce ectodermal appendages, which later grow as teeth (Smith, 2003; Soukup et al., 2008). Cell-cell signaling and cell differentiation between the ectoderm and mesenchyme cells regulate tooth morphogenesis. Many paracrine signal molecules that we know are involved, and mediate communication during tooth development. Most of these signals are from the Hedgehog (Hh), Ectodysplasin (Eda), transforming growth factor ß (TGFß), Wnt, Bone morphogenic protein (Bmp) and fibroblast growth factor (FGF) conserved signaling groups (Jernvall and Thesleff, 2000). These conserved signaling families also play significant roles in regulating many other aspects of embryonic development. They not only regulate communication between germ layers, but also within each germ layer. The variation in mammalian dentition relies on these cell signals to regulate differentiation, thus they are present from start to finish of too...
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Even after reprogramming the cells for tooth development, the techniques used in this process will have to take into account the natural environment of the cells. Based on the current understanding of tooth development that we have seen above, it is clear that the techniques used in tooth bioengineering will be of significantly higher complexity than that of reprogramming pancreatic cells, and this would have to be done inside the oral cavity.
A clear understanding of the mechanisms involved in normal tooth development is required to develop methods of programming tooth regeneration in humans. The stem cells in mammalian teeth might not be a good source for bioengineering due to their limited supply and problematic collection methods. Non-dental stem cells such as iPSCs is thus far shown to be one of the most promising tooth bioengineering avenues to explore.
The cells unique nature has scientists intrigued to do research with the focus of finding a way that these cells can be used to replace patients’ injured or diseased tissues. Advancement is made to all the three types of stem cells namely embryonic stem cells, adult stem cells in addition to induced pluripotent cells. Embryonic cells are the building blocks of an embryo that is developing, and can develop into almost all body cell types. Somatic cells are found in the body tissues. They renew and regenerate in healthy bodies. The third type which is induced pluripotent is genetically modified embryo cells from skin cells.2 Research on these cells are geared towards saving humanity; a noble course.
“What are the potential uses of human stem cells and the obstacles that must be overcome before these potential uses will be realized?” . InStem Cell Information. Bethesda, MD: National Institutes of Health, U.S. Department of Health and Human Services, 2009.
Tooth surfaces are referred to by various names in dentistry, including mesial, distal, buccal, and lingual. If you drew a midline t...
All primates have essentially the same kinds of specialized mammalian teeth adapted to eating a wide variety of foods. Beginning at the front, each quadrant of the mouth has 2 incisors, 1 canine, and varying numbers of premolars and molars. The incisors are used like scissors for nipping off pieces of food. The pointed canines are for piercing and tearing. The premolars and molars, with their cusps, are used to grind and smash food. In platyrrhine species, there are 3 premolars and 2 or 3 molars. This results in a dental formula of 2.1.3.2 or 2.1.3.3. In contrast, all of the catarrhines have 2 premolars and 3 molars, making a dental formula of 2.1.2.3. The chimpanzee shown below is an Old World anthropoid species and, therefore, has a catarrhine dental formula.
The importance of embryonic stem cells rests in their lack of specialization. These basic cells are present in the earliest stages of developing embryos and are able to develop into virtually any type of cell and tissue in the body. Being self-renewing, they offer a potentially limitless source of cells and tissue. (Tucker)
Everyone has teeth, and society likes them to be as white as possible. But does everyone know the parts of the tooth? The tooth has four parts: dental pulp, dentin, enamel, and cementumcentenum. Dental pulp is the center part of the tooth and is made of tissue and nerves. Dentin is connected to the dental pulp and is the second hardest part of the tooth. Enamel is the hard, outer layer that surrounds the tooth. Enamel cannot be repaired or replaced. One can only prevent its loss, which is why we brush our teeth so often to help eliminate the plaque and acids that certain sodas and other sugary drinks try so hard to remove. Without enamel, teeth would erode within days of their coming in. And last but not least, cementumcentenum. CementumCentenum covers the root of the tooth and it anchors the root to the skin.
Dental formula and total dentition- Giraffes have no upper incisors or canines but have a long diastema between both cheeks, the dental formula is 0:0:3:3
The article Poor Teeth was written by Sarah Smarsh with the goal in mind being to shed light on the issue between upper and lower class society in a particularly concrete way. Teeth and dental health are an easy thing for people to imagine in their head because everyone has a set whether they’re white and shiny or black and rotted. This makes it easy to draw a comparison between people that care for their teeth and those who don’t. However, access to dental knowledge and services which the lower class often times doesn’t have is very different between the poor and the rich. While the rich stroll through life showing off their perfect glossy white rows of teeth, there are less privileged people out there with barren mouths whose weak pale gums
For the past five weeks we have studied gender and psychoanalysis in horror films. Over the duration of our studies, I have learned much more about the abject and how gender in regards to female genitalia is conveyed in some horror films. The object that I decided to write my object analysis about is the film Teeth directed and written by Mitchell Lichtenstein. The film surrounded most of its attention on the protagonist Dawn and the horrors created by her vagina. In the beginning of the film Dawn remains celibate and refrains from anything that will sexually arouse her, including movies and male friends. As the film persists, Dawn eventually is raped by her crush, Tobey, during their sexual encounter Tobey’s penis is suddenly chopped off from
Carnivores have highly developed jaw lines called the temporalis muscle with wider mouths related to their head size. Their teeth are like canine teeth and they tend to chew up and down, not side to side. A few carnivores have enough energy to go without hunting for several days.
The first neural induction in amphibian embryos has given the Nobel Prize in Medicine award to Hans Spemann in 1935 for his “Spemann-Mangold organizer” paper. The discovery with her student Hilde Mangold leads to establishment of a neuroectodermal primordium from where the nervous system arise involving induction of chemicals such as the fibroblast growth factor (FGF) and WNT signalling, together with inhibition of bone morphogenetic protein-4 (BMP) signalling activity to promotes neuron development. Spemann’s study has successfully identified a morphologically distinct cluster of mesodermal cell located in dorsal lip of blastophore known as ‘organizer’ which has the potential in neural induction. BMP will trigger neural induction and are formed during the gastrulation in vertebrate embryo which is secreted by ventral gastrula signalling centre (Spermann H, Mangold H, 1924). In a normal mechanism BMP binds with receptor on ectoderm cell to form epidermis. However, by inhibiting BMP, ectoderm cells will differentiate to form the neurons cells without the presence of neural inducers t...
“Stem Cells: The Future of Medicine.” Medschool.umaryland.edu. University of Maryland School of Medicine Web 14 Nov 2013
A nice smile makes you look great and helps maintain optimal health. Luckily, regular brushing with your favorite toothpaste, along with regular dentistry, will keep your teeth whiter and healthier. One thing for young adults to be aware of is that you have some new teeth coming! Your wisdom teeth are the last of your 32 pearly whites to grow through your gums, normally appearing after the age of 18, but before you turn 25. Technically, they are your final set of molars, and most often, they grow in with no problems. However, sometimes, they don’t have enough room and become tilted, displaced or twisted, causing pain and damaging other teeth.
The cap stage occurs during the ninth to tenth week of development. The cap stage is where further growth of the bud that becomes indented and covers the connective tissue that is called the dental papilla; the cells of the cap are morphodifferentiated into four layers namely the enamel organ (previously dental lamina), dental papilla and dental sac (previously mesenchyme cells). During the cap stage, the growth and differentiation of different tissues involved give rise to distinct function and morphology of the tooth components. The dental cap is formed as a result of the morphodifferentiation of mesenchyme cells which surround the enamel organ. The term “cap” is used because the tissue formed encapsulates the enamel organ. The invagination between two “lobes” of the dental sac gives rise to dental papilla. According to Ten Cate’s Oral Histology textbook, when the enamel knot is formed, there are many signaling molecules that are expressed, including Bmp2, Bmp4, Bmp7, Fgf4, Fgf9, Wnt10b, Slit1 and Shh. The enamel knot signals are formed at the future cusps (example: molars) Eventually, the enamel organ will form the enamel, the dental papilla will form the dentin and pulp, and the dental sac will form the supporting structures of a tooth (peridontium, cementum and the alveolar
The field of regenerative medicine encompasses numerous strategies, including the use of materials and de novo generated cells, as well as various combinations thereof, to take the place of missing tissue, effectively replacing it both structurally and functionally, or to contribute to tissue healing[29]