Letter | Published:

Dental notation: Mental gymnastics

BDJ volume 223, page 551 (27 October 2017) | Download Citation

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Sir, I must wholeheartedly agree with Mr M. V. B. Nelson (BDJ 2017;223: 3) regarding the confusion caused by the FDI notation. The FDI system falls down because numbers are used to represent two entirely different things, that is, both the individual teeth and the quadrant in which the tooth is situated. The most common typing error is transposition which would radically change the meaning without necessarily being detectable. The FDI system involves mental gymnastics to translate digital numbers into meaningful anatomical directions. For this reason it is much more prone to error.

It seems that the persistence of the FDI system represents the triumph of officialdom over common sense.

Three components are necessary to communicate a specific tooth.

  1. The arch: (upper or lower)

  2. The side of the mouth: (left or right)

  3. The individual teeth: (1-8 for permanent and A–E for deciduous teeth).

It is simply a matter of stating these clearly in a consistent order.

The system described by Mr Nelson and indeed by myself some 24 years ago (BDJ 1993;174: 91) has clarity, lacks ambiguity and as such minimises the chance of wrong extraction error.

1. Preston

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    • M. J. Trenouth


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