Tissues of the Periodontium Presented by: Rita Ann Classe, RDH, BS

What’s foundation got to do with it?

The Periodontium What is it? Why is it important? 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: Demarcations: Gingival margin- coronal boundary Alveolar mucosa- apical boundary Demarcations: Free gingival groove- separates free and attached gingiva Mucogingival 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. TRUE FALSE

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 PDL Supportive 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. TRUE FALSE

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.