Nomenclature, Tooth Numbering Systems & Chronology of Teeth Eruption

Vocabulary flashcards summarizing key terms, structures, surfaces, numbering systems, and eruption chronology from the lecture notes.

Maxillary Arch

The upper jaw arch that houses the maxillary (upper) teeth.

Mandibular Arch

The lower jaw arch that houses the mandibular (lower) teeth.

Quadrant (Dental)

One of the four sections into which the dentition is divided: upper-right, upper-left, lower-left, and lower-right.

Anterior Teeth

Incisors and canines; front teeth used for cutting and tearing food.

Posterior Teeth

Premolars and molars; back teeth used for chewing and grinding food.

Incisors

Sharp-edged front teeth that cut food and guide it into the mouth.

Canines

Pointed teeth that tear food; located lateral to incisors.

Premolars

Transitional teeth that assist canines and molars in crushing and grinding food; absent in primary dentition.

Molars

Largest posterior teeth that perform the bulk of grinding and chewing.

Primary (Deciduous) Dentition

The first set of 20 temporary teeth that erupt from ~6 months to ~33 months of age.

Permanent Dentition

The second set of 32 teeth that replace primary teeth beginning around age 6.

Diphyodont

Having two successive sets of teeth—primary and permanent—during a lifetime.

Dental Formula (Primary)

I 2/2, C 1/1, M 2/2 = 20; indicates no premolars in primary dentition.

Dental Formula (Permanent)

I 2/2, C 1/1, PM 2/2, M 3/3 = 32.

Crown (Tooth)

The visible part of a tooth above the gingiva.

Root (Tooth)

The part of a tooth embedded in the jawbone sockets.

Enamel

Hard, white outer covering of the crown; hardest tissue in the body.

Dentin

Calcified tissue beneath enamel and cementum; forms bulk of the tooth.

Pulp

Soft tissue in the center of the tooth containing nerves and blood vessels.

Cementum

Yellowish outer layer covering the root and anchoring periodontal fibers.

Mesial Surface

Tooth surface closest to the midline of the face.

Distal Surface

Tooth surface farthest from the midline of the face.

Facial Surface

Any surface of a tooth facing the lips or cheeks.

Labial Surface

Facial surface of anterior teeth that faces the lips.

Buccal Surface

Facial surface of posterior teeth that faces the cheeks.

Lingual Surface

Surface of a tooth that faces the tongue.

Palatal Surface

Lingual surface of maxillary teeth that faces the palate.

Incisal Edge

Cutting edge of an anterior tooth.

Occlusal Surface

Chewing surface of posterior teeth.

Proximal Surface

Surface of a tooth that contacts its neighbor (mesial or distal).

Universal Numbering System

U.S. system using numbers 1–32 for permanent teeth and letters A–T for primary teeth, starting at maxillary right third molar.

FDI Tooth Numbering System

International two-digit code; first digit = quadrant (1-4 permanent, 5-8 primary), second digit = tooth position 1-8 (permanent) or 1-5 (primary) from the midline.

Zigmondy-Palmer Notation

System using right-angle symbols for quadrants and numbers/letters for tooth positions; e.g., UR4 for upper-right first premolar.

Wisdom Teeth

Third molars; normally erupt from ~18 years onward.

Primary Maxillary Eruption Sequence

ABDCE (central incisor, lateral incisor, first molar, canine, second molar).

Primary Mandibular Eruption Sequence

ABCDE (central incisor, lateral incisor, canine, first molar, second molar).

Permanent Maxillary Eruption Sequence

6124 5 7 8 or 6124 3 5 7 8 (1st molar, central incisor, lateral incisor, 1st premolar/canine, 2nd premolar, 2nd molar, 3rd molar).

Permanent Mandibular Eruption Sequence

6123 4 5 7 8 (1st molar, central and lateral incisors, canine, 1st and 2nd premolars, 2nd molar, 3rd molar).

Clockwise Quadrant Coding (FDI)

Quadrants numbered 1-4 for permanent teeth and 5-8 for primary teeth, moving clockwise from the patient’s upper-right.

Eruption Age: Primary Central Incisor

Maxillary: 8-12 months; Mandibular: 6-10 months.

Eruption Age: Permanent First Molar

Approximately 6 years of age in both arches.

ABDCE

Mnemonic for maxillary primary eruption order.

61234578

Mnemonic for mandibular permanent eruption order (1st molar to 3rd molar).