News tagged with teeth

Related topics: dinosaurs · fossil

Group suggests pushing age of adolescence to 24

A small group of researchers with the Royal Children's Hospital in Australia is suggesting that it might be time to change the span of years that define adolescence—from the current 10 to 19 to a proposed 10 to 24 years ...

11 hours ago
popularity1094 comments 0 report

Do girls have stronger teeth than boys?

What if you hardly ever consume soft drinks or eat anything acidic, but still have dental erosion on your teeth? Do genes play a role? And does it matter if you are a boy or a girl?

Jan 10, 2018
popularity35 comments 0

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