Periodontium (Anatomy of periodontium) Part I: BY DR HINA ADNAN DNT 244

Definition The periodontium ( peri= around , odontos= tooth) is the functional system of tissues that surrounds the teeth and attaches them to the jaw bone .

These tissues include: Gingiva. Periodontal ligaments (PDL). Cementum. Alveolar bone.

GINGIVA

GINGIVA Definition: that part of tissue that covers the cervical portions of the teeth and the alveolar processes of the jaws. It is composed of thin outer layer of epithelium and underlying core of connective tissue. The keratinized epithelium immediately surrounds a tooth

Functions: The gingiva provides a tissue seal around the cervical portions of the tooth and alveolar processes of the jaws. resist the mechanical stimuli of hard food particles impinging on it during mastication,

Anatomic Areas: the gingiva is divided into four anatomic areas: Free gingiva. Gingival sulcus. Interdental gingiva (dental papilla). Attached gingiva. Each area of gingiva differ in thickness and histology according to its function

Bounders of the gingiva: The coronal boundary or the upper edge of the gingiva is the gingival margin. The apical boundary or the lower edge of the gingiva is the alveolar mucosa which can be distinguished easily from the gingiva by its dark red color and smooth , shiny surface.

Demarcation of the gingiva: Free gingiva groove: is a shallow linear depression that separates the free gingiva and attached gingiva .( this line can be visible clinically). Mucogingival junction: its clinically visible boundary where the attached gingiva meets the alveolar mucosa.

FREE GINGIVAL also called unattached gingiva or marginal gingiva. Definition: it is the unattached portion of the gingiva that surrounds the tooth in the region of CMJ ( cemtoenamel junction)

Characteristics: Not directly attached to the tooth. Can be stretched away from the tooth surface with a periodontal probe . The free gingiva also forms the soft tissue wall of the gingival sulcus.

Contour of the gingival margin: It meets the tooth in a thin round edge called the gingival margin. The gingival margin follows the contours of the teeth creating a scalloped ( wavy) outline around them.

Gingival sulcus: It is a shallow fissure between marginal gingival and the enamel or cementum. Clinical normal gingival sulcus depth = 2-3 mm measured with periodontal probe.

ATTACHED GINGIVA Definition: is that part of the gingiva that is tightly connect to the cementum on the cervical third of the root and the periostum (connective tissue cover the alveolar bone.) Distance between mucogingival junction and bottom of sulcus.

Function: It allows the gingival tissue to withstand the mechanical forces created during activities such as mastication,speeaking and tooth brushing. It prevents the free gingiva from being pulled away from the tooth when tension is applied to the alveolar mucosa.

Clinical features of gingiva: Surface texture. 7. Position. color. Size. Contour. Shape. Consistency.

color: in healthy gingiva pale or coral pink color: in healthy gingiva pale or coral pink. Can be pigmented which occurs more in dark skinned people . Range from light brown to black.

Size: it’s the sum total of the bulk of cellular elements and their vascular supply . Its common appearance of gingival disease.

Contour: depends on shape of teeth and alignment in the arch.

Shape: shape of the interdental papilla is related with the contour of the proximal tooth. the height of the papilla varies with the location of the proximal contact.

Consistency: gingiva is firm and resilient.

Texture: in healthy Gingiva its similar to an orange peel known as stippling ; it presents in 40% of adults. Stippling is caused by the presence of the connective fibers that attach the gingival tissue to the cementum and bone.

Interdental gingiva (dental papilla) Definition: is the portion of the gingiva that fills the interdental embrasure between two adjacent teeth apical to the contact.

Parts: Facial papilla. Lingual papilla ( papilla= singular noun , papillae = plural noun) the lateral borders and the tip of an interdental papilla are formed by the free gingiva from the adjacent teeth.. the center portion is formed by the attached gingiva.

3- the Col is vallylike depression in the portion of interdental gingiva that lies directly apical to the contact area.

Function: Prevention food from becoming packed between the teeth during mastication.