Tooth Notation For Orthodontic Extraction

Facts and requirements

Request for an orthodontic extraction should be clear and comprehensive (GDC, 2020). Miscommunication that leads to wrong tooth extraction represents 24% of wrong-site surgery and it is a 'never event’ similar to ‘wrong leg amputation' (NHS 2016).

BOS orthodontic extraction guidelines

All orthodontic extraction's request should be in writing using at least one dental notation supplemented with in words description of the tooth number. Supplementary clinical photograph or copy of a radiograph can be used, if required. The written letter should includes patient's demographic information, referral's details, proposed orthodontic treatment plan and updated medical history (BOS 2020).

Dental notation techniques

Two out of the three common notation techniques were developed by German dentists. These include:

1. Original Zsigmondy/Palmer notation: this notation uses a cross structure (+) to denote the four quadrants of the mouth, and 1-8 number or A-E letter to represent permanent and primary dentitions respectively (Zsigmondy 1874, Palmer 1891).

2. Modified Zsigmondy/Palmer notation: Instead of the cross structure in the original version, the modified version uses a upper case letters (UL, UR, LL, LR) to denote the four quadrants of the mouth, and 1-8 number or A-E letter to represent the teeth in permanent and primary dentition respectively (Grace, 2000).

3. Fédération Dentaire Internationale (FDI): It is a two-digit system in which the first digit represents the quadrants in a clockwise fashion while the second digit represents the tooth (Peck 1993). The quadrants of permanent dentition are represented by number 1-4 while that for primary dentition are represented by number 5-8.

4. Universal/national numbering system: It uses consecutive numbering (1-32 for permanent dentition) or letters (A-T for primary dentition) in clockwise fashion to represent the teeth in the mouth (Peck 1993, Muthu 2011).

5. Descriptive and illustrative methods: In this method, teeth are described in words along with radiographs and clinical photography, if possible.


Dental Update Journal in its December 2020 issue published a review paper titled "Update on tooth notation, guidelines for extraction and a new technique for extractions: intra-oral dental marking". The paper was undertaken by a team from UK led by Dr Patel.

The authors proposed a new novel notation system using photographed intra-oral marking to minimise miscommunication. The intra-oral markings are prepared using light cured blue compomer (glass ionomer cements) to mark the teeth that need to be extracted.

The authors stated that this technique meets the WHO surgical safety checklist.

What do you think?

Link to the paper: