Numbering Teeth - Veterinary Online Courses
Lesson 1, Topic 1
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Numbering Teeth

Brett December 12, 2019

Nomenclature and Numbering of Teeth


Incisor Teeth

The incisors will be referred to as: (right or left) (maxillary or mandibular) first, second, or third incisors numbered from the midline. Reference: Peyer B. Comparative odontology. 1st ed. Chicago: University of Chicago Press, 1968;1-347. Nickel R, Schummer A, Seiferle E, et al. Teeth, general and comparative. In: The viscera of domestic mammals. 1st ed. Berlin: Verlag Paul Parey, 1973;75-99.

Premolar Teeth in the Cat:

In the cat, the tooth immediately distal to the maxillary canine is the second premolar, the tooth immediately distal to the mandibular canine is the third premolar.
Reference(s): Nickel R, Schummer A, Seiferle E, et al. Teeth, general and comparative. In: The viscera of domestic mammals. 1st ed. Berlin: Verlag Paul Parey, 1973;75-99.

Tooth Numbering:

The existence of the conventional anatomical names of teeth as well as the various tooth numbering systems is recognized. The correct anatomical names of teeth are (right or left), (maxillary or mandibular), (first, second, third or fourth), (incisor, canine, premolar, molar), as applicable, written out in full or abbreviated. The modified Triadan system is presently considered to be the tooth numbering system of choice in veterinary dentistry; gaps are left in the numbering sequence where there are missing teeth (for example, the first premolar encountered in the feline left maxilla is numbered 206, not 205. The two lower right premolars are 407 and 408, not 405 and 406).

Both the use of anatomical names and the modified Triadan system are acceptable for recording and storing veterinary dental information. The use of anatomical names in publications is required by many leading journals and is recommended. It offers the advantage of veterinary dental publications being understandable to other health professionals and scientists with an interest in veterinary dentistry.

Reference(s): Floyd MR. The modified Triadan system: nomenclature for veterinary dentistry. J Vet Dent 1991; 8:18-19.

In January 1972, the International Dental Federation adopted a new, two digit, user friendly nomenclature system for use in the human dental patient. This new system eliminated the plus and minus signs of the Haderup System and the brackets of the Winkel System. Following the acceptance of the new system for human dental nomenclature, Professor DrMedDent H. Triadan, a dentist at the University of Bern, Switzerland, introduced a similar system for animals. Due to the fact that many animals, including his canine model, have more than nine teeth in a quadrant, the Triadan system for animals utilizes three digits instead of two digits.

Abbreviations associated with Teeth:

Tooth (T):        Hard structure embedded in the jaw; used for biting and chewing
Incisor (I):        Incisor tooth
Canine (C):      Canine tooth
Pemolar (P):    Premolar tooth
Molar (M):        Molar tooth
Alveolus (A):    Socket in the jaw for a tooth root or reserve crown (plural: alveoli)
Crown (C):       Coronal portion of a tooth
Root (RO):        Radicular portion of a tooth
Apex (AP):       End of the root or reserve crown (plural: apices)