Tissues of the Periodontium

Presented by: Rita Ann Classe, RDH, BS

What’s foundation got to do with it?

The Periodontium

What is it? Functional system

of tissues that surrounds the teeth and attaches them to the jawbone

Why is it important? Essential to the

understanding of the normal function of the periodontium, disease prenvention, and the periodontal disease process

Tissues of the Periodontium

Gingiva

Cementum

Periodontal ligament

Alveolar bone

Functions of the Periodontium

Provides seal around cervical portion (neck) of tooth

Holds tissue against tooth during mastication Suspends and maintains tooth in socket Protects underlying dentin Anchors the ends of the periodontal ligament

fibers to the tooth Surrounds and supports the roots of the tooth

Gingiva Provides a tissue seal around the cervical

portions of the teeth and the alveolar processes of the jaw

Gingiva Boundaries:

Gingival margin- coronal boundaryAlveolar mucosa- apical boundary

Demarcations:Free gingival groove- separates free and

attached gingivaMucogingival junction- where attached

gingiva meets alveolar mucosa

Functions of Gingiva

Provides seal around cervical portion of tooth

Holds tissue against tooth during mastication

Anatomical Areas of Gingiva

Free gingiva (unattached or marginal)

Attached gingiva

Interdental gingiva

Gingival Sulcus

Anatomical Areas of Gingiva

Free Gingiva Unattached portion that surrounds tooth in

area of cementoenamel junction (CEJ) Fits closely around tooth but not directly

attached (turtleneck or cufflike) Meets tooth in a thin rounded edge called

the gingival margin Gingival margin follows contours of teeth

creating a scalloped outline

Attached Gingiva Tightly connected to

cementum on cervical third of root and to periosteum of alveolar bone

Lies between free gingiva and alveolar mucosa

Pale/coral pink or light brown/black in color

Stippling (orange peel) texture

Withstands mechanical forces Prevents free gingiva from

being pulled away from tooth

Interdental Gingiva

Fills area between 2 adjacent teeth Facial and lingual Col=valley-like depression that lies apical to

contact area Prevents food impaction

Gingival Sulcus V-shaped, shallow space

around tooth Located between the free

gingiva and tooth surface Base of sulcus formed by

junctional epithelium Depth in health is 1-3mm

One function of the gingva is to provide a seal around the cervical portion of the tooth.

TRUEFALSE

Periodontal Ligament (PDL) Layer of soft connective tissue that covers

root and attaches it to the bone of the tooth socket

Composed mainly of fiber bundles Fibers of PDL attach on one side to the root

cementum and on the other side to the alveolar bone of tooth socket

Functions of PDLSupportive

Sensory

Nutritive

Formative

Resorptive

Cementum

Layer of hard, mineralized tissue that covers dentin surface of root

Light yellow in color Resistant to resorption Receives nutrients from the PDL No nerve or blood supply

Functions of Cementum Anchors PDL to tooth

Protects underlying dentin

Compensates for occlusal tooth

wear

The function of the PDL is to protect the underlying dentin.

TRUEFALSE

Alveolar Bone (Alveolar Process) Bone of the upper or lower jaw that

surrounds and support the roots of the teeth Dependent on presence of tooth

Function of Alveolar Bone

Forms the bony sockets that provide support and protection for the roots of the teeth

Components of Alveolar Bone

Alveolar bone proper (cribiform plate) Alveolus Cortical bone Alveolar crest Cancellous bone (spongy bone) Periosteum

Let’s Review

Let’s Review

Provides seal around cervical portion (neck) of tooth

Holds tissue against tooth during mastication Suspends and maintains tooth in socket Protects underlying dentin Anchors the ends of the periodontal ligament

fibers to the tooth Surrounds and supports the roots of the tooth

Which Foundation Do You Want?

References

Nield-Gehrig, J.S. and Willmann, D.E. (2008). Foundations of Periodontics for the Dental Hygienist, Second Edition. Baltimore, MD: Lippincott Williams & Wilkins.