króliki-i-zające: Tooth

Evidence: 59 • authority: 71

As I noted last week , animals are monophyodonts, diphyodonts, or polyphyodonts. Rodents and some cetaceans, for example, are monophyodonts—their teeth grow continuously and are never replaced. Humans, and most other mammals, are diphyodonts—they normally have two sets of teeth (dentitions), although the numbers of teeth in each dentition are different, so that the 20 deciduous or milk teeth and their replacements can be thought of as diphyodontal (Figure 1) and the other 12 as monophyodontal. Kangaroos, elephants, and manatees, unique among mammals, and some non-mammalians species, typically fishes and reptiles, are polyphyodonts, animals whose teeth are repeatedly replaced during their lives. Jeffrey Aronson: When I Use a Word . . . Being one, two, or many - The BMJ The prefixes in these words are all Greek. “Mono” is from μόνος, alone, solitary, or unique; “di” is from δισσός, twofold or double; and “poly” is from πολύς, one of whose many meanings is “many”, or in this case “more than two”. This is reminiscent of counting systems that go “ one, two, many ”, like those of the Australian Walpiri, or the Gumulgal from the Torres Strait, or the Pirahã of the Amazon, or like the rabbits in Richard Adams’s novel Watership Down , who can only count up to four, above which everything else is “hrair”, a lot.

Evidence: 100 • authority: 72

A tooth (pl.: teeth) is a hard, calcified structure found in the jaws (or mouths) of many vertebrates and are used to break down food. Some animals, particularly carnivores and omnivores, also use teeth to help with capturing or wounding prey, tearing food, for defensive purposes, to intimidate other animals often including their own, or to carry prey or their young. The roots of teeth are covered by gums. Teeth are not made of bone, but rather of multiple tissues of varying density and hardness that originate from the outermost embryonic germ layer, the ectoderm. The general structure of teeth is similar across the vertebrates, although there is considerable variation in their form and pos…

Evidence: 79 • authority: 72

A diphyodont is any animal with two sets of teeth, initially the deciduous set and consecutively the permanent set. Most mammals are diphyodonts—as to chew their food they need a strong, durable and complete set of teeth. Diphyodonts contrast with polyphyodonts, whose teeth are constantly replaced. Diphyodonts also differ from monophyodonts, which are animals who have only one set of teeth that does not change over a long period of growth. In diphyodonts, the number of teeth that are replaced varies from species to species. In humans, a set of twenty deciduous teeth, or "milk teeth", are replaced by a completely new set of thirty-two adult teeth. In some cases hypodontia or hyperdontia occu…

Evidence: 59 • authority: 72

Deciduous teeth or primary teeth, also informally known as baby teeth, milk teeth, or temporary teeth, are the first set of teeth in the growth and development of humans and other diphyodonts, which include most mammals but not elephants, kangaroos, or manatees, which are polyphyodonts. Deciduous teeth develop during the embryonic stage of development and erupt (break through the gums and become visible in the mouth) during infancy. They are usually lost and replaced by permanent teeth, but in the absence of their permanent replacements, they can remain functional for many years into adulthood.

Evidence: 45 • authority: 72

Horse teeth refers to the dentition of equine species, including horses and donkeys. Equines are both heterodontous and diphyodontous, which means that they have teeth in more than one shape (there are up to five shapes of tooth in a horse's mouth), and have two successive sets of teeth, the deciduous ("baby teeth") and permanent sets. For grazing animals, good dentition is essential to survival. Continued grazing creates specific patterns of wear, which can be used along with patterns of eruption to estimate the age of the horse.

Evidence: 38 • authority: 88

Comparative analysis of transcriptomes between apical pulp‐derived cells from deciduous teeth and permanent teeth or dental pulp cells from exfoliated deciduous teeth. Abstract Background The present study aimed to explore the differences between apical pulp‐derived cells of deciduous teeth (De‐APDCs) and apical pulp‐derived cells of permanent teeth (P‐APDCs)/dental pulp cells from exfoliated deciduous teeth (De‐DPCs). Methods Three types of cells (De‐DPCs, P‐APDCs and De‐APDCs) were cultured by the tissue explant method. Transcriptome sequencing for the three types of cells was conducted and the differentially expressed genes (DEGs) between groups were selected. The potential biological fu…

Evidence: 38 • authority: 80

The variability of eruption of permanent teeth and loss of deciduous teeth in Western Australian children

Evidence: 38 • authority: 80

Sealants on deciduous or permanent teeth

Evidence: 38 • authority: 92

The Peridental Structures of Equine Cheek Teeth: An Age-Dependent Anatomical Study of Maxilla and Mandible.. Sequestration is the most common complication following equine cheek tooth extraction, occurring predominantly in the mandible of younger horses. Extraction-related trauma to the peridental region may impair healing. Despite its clinical relevance, detailed knowledge of peridental anatomy remains limited. This study investigated age-related differences in the peridental region of maxillary and mandibular equine cheek teeth 07 to 09. The peridental region of 24 cheek teeth rows from six cadaver heads was sectioned horizontally at approximately 10 mm intervals. Sections were photograph…

Evidence: 38 • authority: 80

Why Mammals Grow Teeth Only Twice: Implications for the Safety and Ethics of Tooth-Regeneration Drugs Author

Evidence: 38 • authority: 80

The variation in eruption of permanent teeth and loss of deciduous teeth in Western Australian children

Evidence: 38 • authority: 92

Development of tooth regenerative medicine strategies by controlling the number of teeth using targeted molecular therapy.. Analysis of various genetically modified mice, with supernumerary teeth, has revealed the following two intrinsic molecular mechanisms that increase the number of teeth. One plausible explanation for supernumerary tooth formation is the rescue of tooth rudiments. Topical application of candidate molecules could lead to whole tooth formation under suitable conditions. Congenital tooth agenesis is caused by the cessation of tooth development due to the deletion of the causative gene and suppression of its function. The arrest of tooth development in Runx2 knockout mice,…