Overview of Dentitions

Flashcards covering key concepts related to dentitions, tooth designation, tooth anatomy, and tooth form.

What is a dentition?

The term used to describe the natural teeth in the jaws.

How many dentitions does a person have in their lifetime?

Two: primary dentition and permanent dentition.

What tooth types are included in the primary dentition?

8 incisors, 4 canines, and 8 molars, for a total of 20 teeth.

What tooth types are included in the permanent dentition?

8 incisors, 4 canines, 8 premolars, and 12 molars, for a total of 32 teeth.

What is the most widely used tooth designation system in the United States?

The Universal Numbering System (UNS).

How are primary teeth designated in the Universal Numbering System?

By using capital letters A through T.

How are permanent teeth designated in the Universal Numbering System?

By using the digits 1 through 32.

What is the International Numbering System (INS)?

A tooth designation system accepted by the International Standards Organization (ISO) and the World Health Organization (WHO), based on the Fédération Dentaire Internationale (FDI) system.

How does the International Numbering System designate teeth?

By using a two-digit code, where the first digit indicates the quadrant and the second indicates the tooth’s position in that quadrant.

What is the Palmer Notation Method?

Another system commonly used in orthodontics, also known as the Military Tooth Numbering System, designating teeth with a right-angle symbol indicating the quadrants and arch, with the tooth number placed inside.

What are the three dentition periods?

Primary, mixed, and permanent.

When does the primary dentition period occur?

Approximately between 6 months and 6 years of age.

When does the mixed dentition period occur?

Approximately between 6 and 12 years of age.

When does the permanent dentition period begin?

Just after 12 years of age, with the shedding of the last primary tooth.

What is the alveolus?

The bone of the tooth socket that surrounds and supports each tooth.

What is the alveolar process?

The tooth-bearing part of each jaw, where each alveolus is located.

What are the maxillary and mandibular arches?

The alveolar processes of the maxilla and mandible, respectively.

What is occlusion?

The method by which the teeth of the mandibular arch come into contact with those of the maxillary arch.

What is a midline?

An imaginary vertical plane that divides each dental arch into two approximately equal halves.

What are anterior teeth?

Incisors and canines, which are closer to the midline.

What are posterior teeth?

Molars (and premolars, if present), which are farther from the midline.

What is the D-A-Q-T System?

A system for describing an individual tooth based on dentition, arch, quadrant, and tooth type.

What are sextants?

Divisions of each dental arch into three parts: right posterior, anterior, and left posterior.

What are the parts of a tooth?

A crown and one or more roots.

What is the anatomic crown?

The part of the tooth covered by enamel.

What is the clinical crown?

The part of the anatomic crown that is visible and not covered by the gingiva.

What is the anatomic root?

The part of the root covered by cementum.

What is the clinical root?

The part of the anatomic root that is visible.

What is the root axis line (RAL)?

An imaginary line representing the long axis of a tooth, drawn to bisect the root and crown in the cervical area.

Where are root concavities commonly found?

On the proximal root surfaces of anteriors and posteriors, and the buccal and lingual surfaces of molars.

What is a furcation?

The area between two or more roots.

What are full artificial crowns?

Restorations that cover the entire anatomic crown area.

What is crown lengthening?

A surgical periodontal procedure to increase the amount of the clinical crown and reduce the surrounding gingival tissue by removal.

What is biologic width?

The distance established by the junctional epithelium and connective tissue attachment to the root surface of a tooth.

What is crown-to-root ratio?

The proportional relationship between the part of the tooth above the alveolar crest compared to the part of the tooth below the alveolar crest.

What are the five surfaces of a tooth?

Facial, lingual, masticatory, mesial, and distal.

What is the facial surface?

The tooth surface closest to the surface of the face.

What are labial and buccal surfaces?

Labial is the facial tooth surface closest to the lips, and buccal is the facial tooth surfaces closest to the inner cheek.

What is the lingual surface?

The tooth surface closest to the tongue.

What is the palatal surface?

The lingual surface closest to the palate on the maxillary arch.

What is the masticatory surface?

The chewing surface on the most superior surface of the crown; incisal for anterior teeth and occlusal for posterior teeth.

What are mesial and distal surfaces?

Mesial is the surface closest to the midline, and distal is the surface farthest away from the midline.

What are proximal surfaces?

The mesial and distal surfaces between adjacent teeth.

What is the interproximal space?

The area between adjacent tooth surfaces.

What is a contact area?

The area where the crowns of adjacent teeth in the same arch physically touch on each proximal surface.

What is the height of contour?

The greatest elevation of the tooth either incisocervically or occlusocervically on a specific surface of the crown when viewing its profile from the labial or buccal and the lingual.

What are embrasures?

Triangular-shaped spaces between two teeth created by the sloping away of the mesial and distal surfaces.

What is a line angle?

The line created at the junction of two crown surfaces.

What is a point angle?

The junction of three surfaces of the crown.

What is the function of incisors?

To bite and cut food during mastication.

What is the function of canines?

To pierce or tear food during mastication.

What is the function of premolars?

To assist canines in piercing and tearing food, and assist molars in grinding food during mastication.

What is the function of molars?

To grind food during mastication, assisted by the premolars.