News tagged with teeth

Related topics: dinosaurs · fossil

Scientists discover why teeth form in a single row

(PhysOrg.com) -- A system of opposing genetic forces determines why mammals develop a single row of teeth, while sharks sport several, according to a study published today in the journal Science. When completely understood, ...

Feb 26, 2009
popularity0 comments 0

Pulled teeth stored for stem cells

Naidelys Montoya didn't wait for her son's baby teeth to fall out. She took the boy to an oral surgeon to have two of the loose ones extracted.

Jan 21, 2011
popularity1 comments 2

Chew on this: 6 dental myths debunked

Brushing, flossing, and twice-yearly dental check-ups are standard for oral health care, but there are more health benefits to taking care of your pearly whites than most of us know. In a review article, a faculty member ...

Aug 05, 2010
popularity0 comments 9

Spanish hospital claims first full-face transplant

(AP) -- A team of surgeons has carried out the world's first full-face transplant on a young Spanish farmer unable to breathe or eat on his own since accidentally shooting himself in the face five years ago.

Apr 23, 2010
popularity0 comments 2

Tooth

Teeth (singular tooth) are small whitish structures found in the jaws (or mouths) of many vertebrates that are used to tear, scrape, and chew food. Some animals, particularly carnivores, also use teeth for hunting or defense. The roots of teeth are covered by gums. Teeth are not made of bone, but rather of tissues of varying density and hardness.

Teeth are among the most distinctive (and long-lasting) features of mammal species. Paleontologists use teeth to identify fossil species and determine their relationships. The shape of the animal's teeth are related to its diet. For example, plant matter is hard to digest, so herbivores have many molars for chewing. Carnivores, on the other hand, need canines to kill prey and to tear meat.

Mammals are diphyodont, meaning that they develop two sets of teeth. In humans, the first set (the "baby," "milk," "primary" or "deciduous" set) normally starts to appear at about six months of age, although some babies are born with one or more visible teeth, known as neonatal teeth. Normal tooth eruption at about six months is known as teething and can be painful.

Some animals develop only one set of teeth (monophyodont) while others develop many sets (polyphyodont). Sharks, for example, grow a new set of teeth every two weeks to replace worn teeth. Rodent incisors grow and wear away continually through gnawing, maintaining relatively constant length. Many rodents such as voles (but not mice) and guinea pigs, as well as rabbits, have continuously growing molars in addition to incisors.

This text uses material from Wikipedia, licensed under CC BY-SA

Subscribe to rss feed