Dental Formula - SS1 Biology Lesson Note

The dental formula is a shorthand notation that represents the number and types of teeth in one half of the upper and lower jaws of an animal. It provides a standardized way to describe the dentition of different species. The dental formula typically consists of numerical symbols representing the teeth types and their counts. Here are a few examples of dental formulas for different animals:

1.     Human Dental Formula:

§  Permanent teeth: 2-1-2-3 / 2-1-2-3

§  Milk teeth (deciduous teeth): 2-1-2-0 / 2-1-2-0

2.     Dog Dental Formula:

§  Permanent teeth: 3-1-4-2 / 3-1-4-3

§  Milk teeth (deciduous teeth): 3-1-3-0 / 3-1-3-0

In the dental formula, each number represents the count of a specific type of tooth. The types of teeth are usually represented by abbreviations:

§  Incisors (I)

§  Canines (C)

§  Premolars (P)

§  Molars (M)

The dental formula is written for one half of the upper jaw and one half of the lower jaw, as the dentition is usually symmetrical on both sides.

For example, the human permanent dental formula (2-1-2-3 / 2-1-2-3) indicates that on one half of the upper jaw and one half of the lower jaw, there are 2 incisors, 1 canine, 2 premolars, and 3 molars in both the upper and lower arches. The same notation applies to milk teeth, with the difference being the absence of the third molars (wisdom teeth) in the deciduous dentition.