Cast of a human upper jaw showing incisors, canines, premolars, and 2 out of 3 sets of molars. Incisors (from Latin incidere, "to cut" are the first kind of Tooth in Heterodont Mammals They are located in the Premaxilla "Cuspid" redirects here For the heart valves see Bicuspid valve and Tricuspid valve. Molars are the rearmost and most complicated kind of Tooth in most Mammals In many mammals they grind food hence the Latin name mola, " Millstone

Dentition is the development of teeth and their arrangement in the mouth. Tooth development is the complex process by which teeth form from Embryonic cells, grow, and erupt into the Mouth. The mouth, buccal cavity, or oral cavity is the first portion of the Alimentary canal that receives food and begins digestion by mechanically breaking up

All mammals except the monotremes, the edentates, the pangolins, and the cetaceans have up to four distinct types of teeth, with a maximum number for each. Mammals ( class Mammalia) are a class of Vertebrate Animals characterized by the presence of Sweat glands, including sweat glands Monotremes (from the Greek monos 'single' + trema 'hole' referring to the Cloaca) are Mammals that lay eggs ( Prototheria) instead The superorder Xenarthra is a group of Placental mammals (infraclass Eutheria extant today only in the Americas The Order Cetacea (sɪˈteɪʃiə L cetus, whale includes Whales Dolphins and Porpoises Cetus is These are the incisor (cutting), the canine, the premolar, and the molar (grinding). Incisors (from Latin incidere, "to cut" are the first kind of Tooth in Heterodont Mammals They are located in the Premaxilla "Cuspid" redirects here For the heart valves see Bicuspid valve and Tricuspid valve. Molars are the rearmost and most complicated kind of Tooth in most Mammals In many mammals they grind food hence the Latin name mola, " Millstone Mammals that have distinct types of teeth are heterodont; others are homodont. The anatomical term heterodont (from Greek, meaning 'different teeth' refers to Animals which possess more than a single tooth morphology.

The number of teeth of each type is written as a dental formula for one side of the mouth, with the upper and lower teeth shown on separate rows. The number of teeth in a mouth is twice that listed as there are two sides. In each set, incisors are indicated first, canines second, premolars third, and finally molars. Incisors (from Latin incidere, "to cut" are the first kind of Tooth in Heterodont Mammals They are located in the Premaxilla "Cuspid" redirects here For the heart valves see Bicuspid valve and Tricuspid valve. Molars are the rearmost and most complicated kind of Tooth in most Mammals In many mammals they grind food hence the Latin name mola, " Millstone For example, the formula 2. 1. 2. 3 for upper teeth indicates 2 incisors, 1 canine, 2 premolars, and 3 molars on one side of the upper mouth.

The human dental formula is:

Of cats it is:

The last upper premolar and first lower molar of the cat, since it is a carnivore, are called carnassials and are used to slice meat and skin. The diverse order Carnivora (kɑrˈnɪvərə or sometimes /ˌkɑrnɪˈvɔərə/ from Latin carō (stem carn-) "flesh" + vorāre Carnassials are large teeth found in many Carnivorous Mammals, used for shearing flesh and bone in a Scissor or Shear -like way The armadillo, being homodont, has a dental formula that is simply 7/7. Armadillos are small Placental Mammals known for having a leathery armor shell

The maximum dental formula for placental mammals is:

Non-placental mammals such as marsupials can have more teeth than placentals. Marsupials are an Infraclass of Mammals characterized by a distinctive pouch (called the marsupium) in which females carry their young through The opossum's dental formula is:

In many mammals the children have a set of teeth that fall out and are replaced by adult teeth. These are called deciduous teeth, baby teeth or milk teeth. See also Deciduous. "Baby teeth" redirects here For the band of that name see Baby Teeth (band. Animals that have two sets of teeth, one followed by the other, are said to be diphyodont. Normally the formula for milk teeth is the same as for adult teeth except that the premolars are missing.

The milk tooth formula for humans is:

The kitten has 26 teeth. Kittens ( Old English Diminutive of Cat) are juvenile domesticated cats ( Felis catus) that are not fully-grown

Teeth are numbered starting at 1 in each group, except the premolars which end at 4. This means that the carnassials are always the fourth upper premolar and the first lower molar. Thus the human teeth are I1, I2, C1, P3, P4, M1, M2, and M3.

Other uses: Dentition in archaeology

Dentition, or the study of teeth, is an important area of study for archaeologists, especially those specializing in the study of older remains. Dentition affords many advantages over studying the rest of the skeleton itself (osteometry). Osteometry is the study and Measurement of Human or Animal Skeleton, especially in an Anthropological or Archaeological The structure and arrangement of teeth is constant and, although it is inherited, does not undergo extensive change during environmental change, dietary specializations, or alterations in use patterns. The rest of the skeleton is much more likely to exhibit change because of adaptation. Teeth also preserve better than bone, and so the sample of teeth available to archaeologists is much more extensive and therefore more representative.

Dentition is particularly useful in tracking ancient populations' movements, because, although all humans have the same basic 32 teeth, there are subtle differences in the shapes of incisors, the number of grooves on molars, and extra cusps on particular teeth. These differences can not only be associated with different populations across space, but also change over time so that the study of the characteristics of teeth could say which population one is dealing with, and at what point in that population's history they are.

References

Adovasio, J. M. and David Pedler. "The Peopling of North America. " North American Archaeology. Blackwell Publishing, 2005. p. 35-36.

External links

• Colorado State's Dental Anatomy Page