Cheat Sheet

Dental Anatomy and Terminology Basics:
Terms and Definitions

Module 1 - Dental Anatomy Basics

• Alveolar Bone

  • The bone that holds the teeth in the jaw.

• Gingiva

  • The soft tissue that covers the alveolar bone and surrounds the teeth.

• Subgingival area

  • Structures that lie below the gumline.

• Crown

  • The visible part of the tooth.

• Cervix

  • The neck of the tooth where the crown meets the root.

• Root

  • The anchor of the tooth that extends into the jawbone and holds the tooth in place.

• Apex

  • The tip of the root of the tooth.  The nerves and blood supply enter and leave through the opening at the tip of the apex.

• Enamel

  • The protective, outer surface of the crown of the tooth.  Enamal is the hardest material in the body.

• Dentin

  • Makes up the majority of the inner portion of the tooth.  On x-rays, it appears darker than enamel.

• Pulp

  • The area inside the tooth that holds the nerves and blood vessels which provide nutrients to the tooth.  It is in the center of the tooth and is in both the crown and the root.

• Cementum

  • Makes up the outer surface of the root of the tooth.  It covers the dentin on the root portion of the tooth and helps to hold the tooth in place.  Cementum is much softer than enamel.

Module 2 - Dental Terminology Basics

• Eruption

  • The movement of teeth through the alveolar bone and gingival tissues.

• Partial eruption

  • Teeth that have not fully emerged but are in the process of eruption.

• Impacted

  • A tooth that does not erupt.

• Maxillary Arch

  • The upper arch and is a fixed structure that is part of the skull.  The abbreviation is MAX or MX.

• Mandibular Arch

  • The lower arch is hinged with the temportal bone of the skull at the temporomandibular joint, commonly known as TMJ.  The abbreviation is MAND or MD.

• Midline

  • The imaginary line drawn through the middle of the face and head, dividing it into two equal parts.  It separates to two arches into two identical left and right halves.

• Quadrants

  • Each dental arch is divided into a right and left quadrant.  The quadrants are formed by the midline, which divides the arch in half.  There are two quadrants per arch that divide the mouth into four equal sections.

• Dentition

  • The development and arrangement of teeth in the mouth.

• Primary Dentition

  • Forms in the womb and begins eruption in children 6 - 8 months old.  It consists of 20 teeth which usually complete eruption by the age of 3.

• Mixed Dentition

  • This is the transition period when a child has some primary and some permanent teeth.  It begins around age 6 and continues until around age 12, when all primary teeth are lost.

• Permanent Dentition

  • Usually begins to erupt at the age of 6 and continues to erupt until around age 21.  It consists of 32 teeth designed to last a lifetime.  They are commonly referred to as adult teeth.

• Primary Dentition Lettering System

  • The primary dentition's lettering system begins in the upper arch with the most posterior (back), upper right tooth.  Lettering begins with the letter A and continues from the patient's right to left around the upper arch, then drops down to the lower arch and ends in the lower right quadrant with the letter T.

• Permanent Dentition Numbering System

  • Similar to the path for primary dentition, the permanent dentition's numbering system begins in the upper arch with the most posterior (back), upper right tooth.  Numbering begins with the number 1 and continues from the patient's right to left around the upper arch, then drops down to the lower arch and ends in the lower right quadrant with the number 32.

• Orthodontic Numbering System

  • Orthodontia uses a different numbering system from the rest of dentistry.  Primary teeth are lettered A through E.  Permanent teeth are numbered 1 through 8.  The numbering system is quadrant based, starting at the front and then moving to the back for each quadrant.

Module 3 - Tooth and Surface Identification

• Anterior Teeth

  • The teeth located in the front of the mouth.  They show when we smile and are used for biting and tearing food.  The are located in both the upper and lower arches and are comprised of a total of 12 teeth.  There are 6 in the upper arch and 6 in the lower arch.  This applies to both primary dentition and permanent dentition.  The abbreviation is ANT.

• Posterior Teeth

  • The teeth located towards the back of the mouth.  They are not as visible when we smile and are used for grinding and chewing food.  They are located in both the upper and lower arches.  For primary dentition, they are comprised of a total of 8 teeth with 4 in the upper arch and 4 in the lower arch.  For permanent dentition, they are comprised of a total of 20 teeth with 10 in the upper arch and 10 in the lower arch.  The abbreviation is POST.

• Anterior Teeth - Central Incisors

  • The two front teeth that are most visible.  Central incisors are used for cutting food.

• Anterior Teeth - Lateral Incisors

  • The teeth to the right and left of the central incisors.  Lateral incisors are used for cutting food.

• Anterior Teeth - Canines

  • The teeth to the right and left of the lateral incisors, going toward the back of the mouth.  Canines are used for tearing and cutting food.  They can also be referred to as cuspids.

• Anterior Teeth - Primary - First Molars

  • The first molars erupt by the age of 13 - 19 months.

• Anterior Teeth - Primary - Second Molars

  • The second molars erupt by the age of 23 - 33 months.

• Posterior Teeth - Permanent - First Premolars

  • The first premolars erupt by the age of 10.

• Posterior Teeth - Permanent - Second Premolars

  • The second premolars erupt by the age of 12.

• Posterior Teeth - Permanent - First Molars

  • The first molars erupt by age 6 and are sometimes referred to as 6-year molars.

• Posterior Teeth - Permanent - Second Molars

  • The second molars erupt by age 12 and are sometimes referred to as 12-year molars.

• Posterior Teeth - Permanent - Third Molars

  • The third molars erupt at age 18 - 21 and are commonly referred to as wisdom teeth.

• Cusps

  • The prominent, biting edge of a tooth.  A canine has 1 cusp, premolars have 2 cusps, and molars usually have 4 cusps.

• Anterior Tooth Surfaces

  • Mesial

    • Refers to the surface of the tooth that is closest to the midline.  The abbreviation is M.

  • Distal

    • Refers to the surface of the tooth that is furthest from the midline.  The abbreviation is D.

  • Facial

    • Refers to the surface of the tooth that is towards the lips and can be seen when we smile.  The abbreviation is F.

  • Incisal

    • Refers to the cutting edge of the tooth.  The abbreviation is I.

  • Lingual

    • Refers to the surface of the tooth that is towards the tongue.  The abbreviation is L.

• Posterior Tooth Surfaces

  • Mesial

    • Refers to the surface of the tooth that is closest to the midline.  The abbreviation is M.

  • Distal

    • Refers to the surface of the tooth that is furthest from the midline.  The abbreviation is D.

  • Buccal

    • Refers to the surface of the tooth that is towards the cheek.  The abbreviation is B.

  • Occlusal

    • Refers to the chewing/grinding surface of the tooth.  The abbreviation is O.

  • Lingual

    • Refers to the surface of the tooth that is towards the tongue.  The abbreviation is L.