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The idea of a tooth worm is a theory of the cause of dental caries, periodontitis and toothaches. Once widespread, the belief is now obsolete, having been superseded by more scientific rationales. It was supposed that the disease was caused by small worms resident within the tooth, eating it away. [1]
The species exist in and have adapted to various ecologies – some in marine environments as distinct as tidal zones and hydrothermal vents, others in fresh water, and yet others in moist terrestrial environments. The Annelids are bilaterally symmetrical, triploblastic, coelomate, invertebrate organisms. They also have parapodia for locomotion.
Gongylonema pulchrum was first named and presented with its own species by Molin in 1857. The first reported case was in 1850 by Dr. Joseph Leidy, when he identified a worm "obtained from the mouth of a child" from the Philadelphia Academy (however, an earlier case may have been treated in patient Elizabeth Livingstone in the seventeenth century [2]).
The water there was in fact a natural underground spring without proper sewage pumping to filter it out from the basement and keep it from going stagnant; as a result, the water had turned to a black sludge-like consistency, and the episode featured multiple shock scenes where the camera focuses in on a large colony of Tubifex worms living there.
The cilia allow the worms to glide along in the water between sand grains, although they also use muscles, allowing the body to twist or contract, for movement. They have no body cavity, and no circulatory or respiratory system. The nervous system is simple, and restricted to the outer layers of the body wall.
Tongue worms grow by moulting, which suggests they belong to Ecdysozoa, while other work has identified the arthropod-like nature of their larvae. [12] In general, the two current alternative interpretations are: pentastomids are highly modified and parasitic crustaceans, probably related to fish lice, or they are an ancient group of stem ...
Hammerhead worms are a part of the phylum Platyhelminthes, which includes all flatworms. This genealogical membership gives them the ability to become two different, genetically identical ...
These worms can reach a length of 3 m (9 ft 10 in), [3] and their tubular bodies have a diameter of 4 cm (1.6 in). Its common name "giant tube worm" is, however, also applied to the largest living species of shipworm, Kuphus polythalamius, which despite the name "worm", is a bivalve mollusc rather than an annelid.