Nomenclature

Dental and Periodontal Anatomy

Topics available:

Dental Anatomy
Nomenclature and Numbering of Teeth
Generations of Teeth in Diphyodont Species
Surfaces of Teeth and Directions in the Mouth
Normal Occlusion
Anatomy of Jaws and TMJ
Anatomy of Tongue, Lips, Palate, Pharynx,
Nose, Face, Salivary Gland and Lymph Nodes


Return to Nomenclature Introduction

Abbeviations to be used in AVDC Case Logs are shown in (blue brackets)



Dental Anatomy

Pulp cavity: Space within the tooth

Pulp chamber: Space within the crown of a tooth

Root canal: Space within the root of a tooth

Apical foramen: Opening at the apex of a tooth, through which neurovascular structures pass to and from the dental pulp

Apical delta: Multiple apical foramina forming a branching pattern at the apex of a tooth reminiscent of a river delta when sectioned and viewed through a microscope that occurs in some brachyodont teeth

Ameloblasts:
Epithelial cells involved in the formation of enamel (amelogenesis)

Enamel (E): Mineralized tissue covering the crown of brachyodont teeth

Anatomical crown (CR/AC): That part of a tooth that is coronal to the cementoenamel junction (or anatomical root)

Clinical crown (CR/CC): That part of a tooth that is coronal to the gingival margin; also called erupted crown in equines

Anatomical root (RO/AR): That part of a tooth that is apical to the cementoenamel junction (or anatomical crown)

Clinical root (RO/CR): That part of a brachyodont tooth that is apical to the gingival margin

Cementoenamel junction: Area of a tooth where cementum and enamel meet

Reserve crown (CR/RC): That part of the crown of a hypsodont tooth that is apical to the gingival margin


Return to Top


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.
Comments:
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)

Return to Top


Generations of Teeth in Diphyodont Species

Deciduous and Permanent are the anatomically correct terms to denote the two generations of teeth in diphyodont species.

It is acceptable to use "primary" instead of deciduous in communicating with clients.
Reference: Anonymous. Nomina Anatomica Veterinaria. 4th ed. Zurich and Ithaca: World Association of Veterinary Anatomists, 1994. Boucher CO, Zwemer TJ. Boucher's clinical dental terminology - a glossary of accepted terms in all disciplines of dentistry. 4th ed. St. Louis: Mosby, 1993. Evans HE. Miller's anatomy of the dog. 3rd ed. Philadelphia: WB Saunders Co, 1993.

Comments: Deciduous is the scientific term used in biology, as well as in comparative anatomy and anthropology for both animal and plant structures which are regularly shed. As a substitute for temporary, the term primary appeared early in the literature and it is listed in both Anthony's and Otofy's dictionaries 1922-23. The style of the Journal of the ADA requires the term deciduous in all literature designed for the profession and allows primary only in discourse for non-professional persons.

Deciduous tooth (DT): Primary tooth replaced by a permanent (secondary) tooth.

The deciduous dentition period is that period during which only deciduous teeth are present.
The mixed dentition period is that period during which both deciduous and permanent teeth are present.
The permanent dentition period is that period during which only permanent teeth are present.
Reference: Anonymous. Nomina anatomica veterinaria. 4th ed. Zurich and Ithaca: World Association of Veterinary Anatomists, 1994. Boucher CO, Zwemer TJ. Boucher's clinical dental terminology - a glossary of accepted terms in all disciplines of dentistry. 4th ed. St. Louis: Mosby, 1993. Evans HE. Miller's anatomy of the dog. 3rd ed. Philadelphia: WB Saunders Co, 1993.

The term "Persistent deciduous tooth" is etymologically correct, although the term "retained deciduous tooth" is commonly used. The latter term, however, can be confused with an unerupted deciduous tooth.
Reference: Eisenmenger E, Zetner K. Tierv§rztliche Zahnheilkunde. 1st ed. Berlin: Verlag Paul Parey, 1982;44-50.



Return to Top


Surfaces of Teeth and Directions in the Mouth

Vestibular/Buccal/Labial
Vestibular is the correct term referring to the surface of the tooth facing the vestibule or lips; buccal and labial are acceptable alternatives.
Reference(s): Anonymous. Nomina Anatomica Veterinaria. 4th ed. Zurich and Ithaca: World Association of Veterinary Anatomists, 1994.
Comment(s): The term "facial" specifically refers to the surfaces of the rostral teeth visible from the front. According to Dr. A.J. Bezuidenhout, a veterinary anatomist at Cornell University, "facial" is a bit of a misnomer. Traditionally "facial" has been used in human dentistry for the aspect of teeth visible from the front, i.e. incisors and canines.

Lingual/Palatal
Lingual: The surface of a mandibular or maxillary tooth facing the tongue is the lingual surface. Palatal can also be used when referring to the lingual surface of maxillary teeth.

Mesial/Distal
Mesial and distal are terms applicable to tooth surfaces. The mesial surface of the first incisor is next to the median plane; on other teeth it is directed toward the first incisor. The distal surface is opposite from the mesial surface.

Rostral/Caudal
Rostral and caudal are the positional and directional anatomical terms applicable to the head in a sagittal plane in non-human vertebrates. Rostral refers to a structure closer to, or a direction toward the most forward structure of the head. Caudal refers to a structure closer to, or a direction toward the tail.

Anterior and posterior are the synonymous terms used in human dentistry.

Return to Top

Return to Nomenclature Introduction