Dental Formula

Introduction to Teeth Formula

Teeth are a set of hard, bony, mineral-rich enamel-coated structures found in the jaws(mouth) that extends into the buccal cavity of most vertebrates which is used to grasp, bite, and chew food. Most of the vertebrates, especially humans have two sets of teeth during their lifespan including temporary and permanent sets of teeth. All humans have teeth of four different types which include incisors, canines, premolar, and molar. But the temporary set does not contain all the four of them.  All the teeth perform several functions like crushing, tearing, cutting, and shredding the food. 

Few animals have the ability to replace their teeth which may be lost due to any disease or injury throughout their life.

Introduction to What is a Dental Formula

The conventional way of describing or expressing the total number of teeth in mammals in which the types of teeth are represented by the first letter i.e incisor (i),  canine (c), premolar (pr), and molar (m) and the number of teeth are written in figures with a fraction above the horizontal line showing the number of teeth, type of teeth on one side of the upper jaw and those below the number of the same type of teeth on one side of the lower jaw according to the arrangement is known as Dental formula.

The Dental Formula is Formulated As

(Half of the upper jaw number of each type of teeth)/(Half of the lower jaw number of the same type of teeth)

Note:- In order to represent the total number of teeth in the mouth, the whole formula is multiplied by two as the formula is for one side of the jaw.

The Dental Formula of Man & Child

Dentition pertains to all types of teeth development and their arrangement in the mouth including teeth numbers. Not all animals have the same type, number, and shape of teeth which are specifically based on their adaptation to the environment, eating habits, and the nutrition they prefer. There are a total of 32 teeth present in a normal adult. Temporary or primary and permanent are two kinds of dentition which are composed of 20 and 32 teeth respectively.

The Dental Formula in Child

There are only 20 teeth present in children that are termed as deciduous teeth or milk teeth. These teeth begin to evolve before the child's birth. Around the age of 6 years, children's teeth begin to erupt or fall out. There are 10 teeth in each arch (both the top and bottom of the jaw)  and five in each quadrant, including two incisors i.e central and lateral (cutting teeth), one canine (tearing teeth), and two molars (grinding teeth). There is not a single premolar present in milk teeth. Hence, children have zero premolars. Dentists rather called premolars as first molars. Adults premolars are replaced by these baby molars. 

The Dental Formula For Deciduous or Milk Teeth Found in Children is

i 2/2 c 1/1 m 2/2 = 10

(2102/2102)×2 = 20

The Dental Formula of Adults

There are a total of 32 teeth except for wisdom teeth in normal adults that are termed as permanent teeth. These teeth start to erupt at the age of 13 years. There are 16 teeth in each arch and eight in each quadrant. Incisors are the eight middlemost teeth (4 up, 4 down) both on the upper and lower jaw. Canines are pointed teeth which are another four teeth (2 up, 2 down) just outside the incisors. Canines also sometimes referred to as bicuspids because their biting surface has pointed cusps. Beyond that are premolars which are total eight in number (4 up, 4 down) present between canines and molars. Molars are a total of six (three pairs) which are flat teeth present in the rear of the mouth. The three pairs of molars are denoted as first, second, and third molar present in the upper and lower jaw. Third molar teeth are also named as wisdom teeth. These teeth come up in the 30s of age but are often removed surgically to prevent other teeth displacement. 

The Dental Formula For Permanent Teeth in Adults is

i 2/2 c 1/1 pm 2/2 m 3/3 =16

(2123/2123)×2 = 32

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Note:- Both humans and monkeys have the same dental formula and a similar set of teeth.

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FAQ (Frequently Asked Questions)

1. What is The Dental Formula of Animals That are Herbivores?

The Dental formula of cattle: Cows and Buffaloes come under the category of cattle and are referred to as domesticated animals who are raised to produce milk. The presence of unique sets of teeth in all the battles makes them fall into the category of cud-chewing animals. There are a total of 32 teeth present in the battles, but they do not have any upper incisors and canines. The dental formula of cattle is represented as (0 incisors 6 premolars and 6 molars)/ 8 incisors 6 premolars 6molars) 

Dental formula = 2×(033/433) = 32

(0/4 incisors, 3/3 premolars, and 3/3 molars)

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2. What is The Dental Formula of Animals?

Dental Formula of many animals differs just like the human from children to adults.

  • The dental formula of sheep: Being herbivores, sheep also have 32 teeth in total which are permanent. 

Dental formula = 2×(033/433) = 32

(0/4 incisors, 3/3 premolars and 3/3 molars)

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  • The dental formula of the cat: Cat is an omnivores animal as it eats both plants and animals. The dental formula of cattle is represented as (6 incisors 2 canines 6 premolars and 2 molars)/ 6 incisors 2 canines 4 premolars 2 molars).

Dental formula: 2×(3131/3121) = 30 teeth.

  • The dental formula of Dog: Dog has a total of 42 teeth. 

Dental formula: 2×(3142/3143) = 42 teeth.

(3/3 incisors, 1/1 canine 4/4 premolars, and 2/3 molars)

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