A Tooth By Any Other Name – A Quick Overview of Dental Nomenclature

You’ve just seen a male who has been assaulted. He’s damaged three of his front teeth and you are going to refer him onto a dentist.

How are you going to describe which teeth are injured ?

Dental pain and tooth injury is not an uncommon reason for a patient to attend an Emergency Department. Whilst many dental problems can be managed in the acute setting by the Emergency Physician we often need to refer these patients on to a dentist, or in some cases Maxillo-Facial Specialists.

We wouldn’t / shouldn’t refer a fracture to the orthopaedic team without being able to provide an adequate description of the clinical and radiological findings. In the same vein we should be able to provide an accurate description of dental injury / pathology. One of the challenges is dental nomenclature, or more simply, which tooth is which ?

There are over 32 different numbering systems used to describe teeth but there are three which are commonly used, and in addition to this notation systems all teeth are named.

Dental Basics

Quick recap on types of teeth.

Permanent Teeth (a.k.a Adult)
  • 32 Teeth
  • First to erupt is first molar ~6-7 yrs old
  • Mixed teeth till all primary teeth lost
Primary Teeth (a.k.a Deciduous / Baby / Milk )
  • 20 Teeth
  • <6 yrs old

Naming Teeth

All teeth are named, depending on whether they are primary or permanent, the order from center to back of a quadrant is:

Permanent Teeth

  • Central Incisor
  • Lateral Incisor
  • Canine
  • First Premolar
  • Second Premolar
  • First Molar
  • Second Molar
  • Third Molar

Primary Teeth

  • Central Incisor
  • Lateral Incisor
  • Canine
  • First Molar
  • Second Molar

Further described as either left or right, and maxillary (upper) or mandibular (lower).

Federation Dentaire Internationale (FDI) Notation

  •  International used system of two digits
  • Used in Australia
  • The first digit denotes the quadrant – Permanent Teeth 1-4 and Primary Teeth 5-8
  • The second digit denotes the tooth – Permanent Teeth 1-8 and Primary Teeth 1-5


Click to enlarge

Palmer Notation Method

  • Commonly used in the UK
  • Quadrant notated by L – shape
  • Permanent teeth numbered 1 – 8
  • Primary teeth A – E
  • Written as number / letter in L

Universal Numbering System

  • Commonly used in the USA
  • Each permanent tooth assigned a number 1 – 32
  • Each primary tooth assigned a letter A – K

Click to enlarge


3 thoughts on “A Tooth By Any Other Name – A Quick Overview of Dental Nomenclature

  1. When I teach the US numbering system, I have people hold their right hand in the air with the index finger pointing. It points to tooth #1. Now rotate your arm 180 degrees until you point down at your “dirty shoe,” which rhymes with 32. They don’t forget this simple mnemonic.

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