Periodontium: The Tooth-Supporting Structures

Vocabulary flashcards covering the key structures, anatomical areas, demarcations, and features of the periodontium and its tissues.

Periodontium

The functional system of tissues that surrounds the teeth and attaches them to the jaw bone, also called the supporting tissues of the teeth or the attachment apparatus.

Gingiva

The part of the mucosa that covers the cervical portions of the teeth and the alveolar processes of the jaws, providing a tissue seal around the neck of the tooth.

Periodontal Ligament (PDL)

A layer of dense fibrous soft connective tissue that covers the root of the tooth, attaching the root cementum on one side to the alveolar bone of the socket on the other side.

Cementum

A thin layer of light yellow, hard, mineralized connective tissue that covers the root of the tooth and anchors the ends of the periodontal ligament fibers.

Alveolar Bone

The mineralized connective tissue of the upper or lower jaw that surrounds and supports the roots of the teeth, forming the bony sockets.

Junctional Epithelium

A specialized type of epithelial tissue that attaches the gingiva to the tooth surface at the base of the gingival sulcus.

Free Gingiva

The unattached portion of the gingiva that surrounds the tooth in the region of the cementoenamel junction (CEJ) in a turtleneck or cufflike manner.

Gingival Margin

The thin, rounded coronal boundary edge where the free gingiva meets the tooth in a scalloped outline.

Free Gingival Groove

A shallow linear depression that separates the free gingiva from the attached gingiva.

Mucogingival Junction

The clinically visible boundary where the pink attached gingiva meets the dark red, shiny alveolar mucosa.

Attached Gingiva

The portion of the gingiva that is tightly connected to the cementum on the cervical third of the root and to the periosteum of the alveolar bone, lying between the free gingiva and alveolar mucosa.

Stippling

A dimpled appearance on the surface of the attached gingiva similar to an orange peel, present in 40% of adults.

Interdental Gingiva

The portion of the gingiva that fills the interdental embrasure between two adjacent teeth apical to the contact area.

Col

A valleylike depression in the portion of the interdental gingiva directly apical to the contact area between adjacent teeth.

Gingival Sulcus

The V-shaped, shallow space between the free gingiva and the tooth surface, measuring 1 to 3 mm in depth in a clinically normal state.

Gingival Crevicular Fluid

A fluid that seeps from underlying connective tissue into the sulcular space, increasing in flow during inflammation or mechanical stimulation.

Alveolar Bone Proper

The thin layer of bone, also known as the cribriform plate, that lines the socket to surround the root of the tooth.

Alveolus

The bony socket or cavity in the alveolar bone that houses the root of a tooth.

Cortical Bone

A layer of compact bone that forms the hard outside wall of the mandible and maxilla on the facial and lingual aspects.

Alveolar Crest

The most coronal portion of the alveolar process, located 1 to 2 mm apical to the CEJ in health.

Cancellous Bone

The latticelike or spongy bone that fills the interior portion of the alveolar process between the cortical bone and alveolar bone proper.

Periosteum

A layer of connective soft tissue covering the outer surface of bone, consisting of an outer collagenous layer and an inner layer of fine elastic fibers.