Dental Nomenclature and Tooth Numbering Systems

• The lecture aims to enable you to know tooth nomenclature, identify common tooth numbering systems, and understand why these systems are used.

Dental Nomenclature

• By using words to describe a tooth, you specify the set, jaw, side, order within a class, and class.
• Set indicates if the tooth is deciduous or permanent.
• Jaw indicates if the tooth is maxillary or mandibular.
• Side indicates if the tooth is on the right or left.
• Order within a class specifies if the tooth is central or lateral, first, second, or third.
• Class indicates if the tooth is an incisor, canine, premolar, or molar.
• An example of dental nomenclature: permanent mandibular right central incisor.

Tooth Numbering Systems

• Numbering systems in dentistry are abbreviations for tooth names.
• Instead of writing "permanent maxillary right central incisor," a number, letter, or symbol is assigned.
• Among the many numbering systems, the Palmer Notation Method, Universal Numbering System, and FDI System are commonly used.

Palmer/Zsigmondy Notation System

• The American Dental Association approved this in 1947.
• Teeth represented by numbers 1-8 designate permanent teeth.
• Teeth represented by letters A-E designate deciduous teeth.
• Two Lines indicates which quadrant the tooth belongs.
• A horizontal line represents the occlusal plane.
• A vertical line represents the midline.
• A permanent maxillary right central incisor is 1 with a horizontal line above the number.
  • A deciduous mandibular left second molar is E with a vertical line to the left.

Universal Numbering System

• The ADA adopted this system in 1968, because the Palmer system was difficult to type on a keyboard.
• Letters designate deciduous teeth consecutively from A to T in a clockwise order.
  • A designates the maxillary right second molar and T designates the mandibular right second molar.
• Numbers designate permanent teeth consecutively from 1 to 32 in a clockwise order.
  • 1 is the maxillary right third molar and 32 is the mandibular right third molar.

FDI Numbering System

• The FDI proposed this system and WHO adopted it.
• Each tooth designated by a two-digit number.
• The left digit indicates the quadrant.
• The right digit indicates the tooth order within the quadrant.
• For the permanent teeth, the quadrants are numbered 1-4.
  • 1 is the right maxillary.
  • 2 is the left maxillary.
  • 3 is the left mandibular.
  • 4 is the right mandibular.
• For the deciduous teeth, the quadrants are numbered 5-8.
  • 5 is the right maxillary.
  • 6 is the left maxillary.
  • 7 is the left mandibular.
  • 8 is the right mandibular.
• The teeth within each quadrant are numbered 1-8 for permanent teeth and 1-5 for deciduous teeth, starting from the central incisor.
• Examples in the FDI system:
  • Mandibular right permanent canine is 43.
  • Maxillary left deciduous lateral incisor is 62.
• A hash (#) can be use before the two digit teeth for FDI system and differentiate the codes between Universal codes and FDI codes.
  • #22 is the permanent maxillary left lateral incisor.
  • 22 is the permanent mandibular left canine.

Learn tooth nomenclature to specify set, jaw, side, order, and class. Identify the Palmer, Universal, and FDI tooth numbering systems as abbreviations for tooth names. Understand the importance of using these systems in dentistry.