ISO system by WHO for teeth notation

Case contributed by Dr Ian Bickle


Normal OPG. Used for numerical teeth notation.

Patient Data

Age: 20 years
Gender: Male

ISO dental notations annotated onto the specific teeth.

The 4 quadrants are shown in different colors for visual ease.

Case Discussion

The International Standards Organization Designation System (ISO System) was developed by the World Health Organization (WHO).  It is a dental notation system commonly used by dental professionals across the world to associate information with a specific tooth.

The ISO System uses a two-digit numbering system in which the first digit represents a tooth's quadrant and the second digit represents the number of the tooth from the midline of the face.

For permanent teeth, the upper right teeth begin with the number, "2". The upper left teeth begin with the number, "1". The lower left teeth begin with the number, "3". The lower right teeth begin with the number, "4". 

For example, the left upper lateral incisor is labeled '22'.  The right lower third molar is labeled '48'.

The normal adult OPT from was used for the purposes of annotation.

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Case information

rID: 57076
Published: 13th Dec 2017
Last edited: 16th Jul 2018
System: Head & Neck
Inclusion in quiz mode: Included
Institution: Rotherham Foundation Hospital Trust

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