The presence or absence of a contact point between the adjacent teeth, the distance between the contact point & the osseous crest Presence or absence of some degree of recession.

Facial & lingual papillae are connected together by a valley-like depression called _____ made up from non keratinized epithelium & represents the most frequent site for initiation of disease process.

"Col"

A -V- shaped shallow crevice around the tooth, bounded by the tooth surface in one side & the epithelial lining the marginal gingiva on the other side.

Gingival sulcus

Clinical normal gingival sulcus depth:

0-3 mm

Gingival Pocket-

Periodontal disease

There is a fluid secreted from gingival C.T into the sulcus through the thin sulcular wall termed as

Gingival fluid.

Components of sulcular fluid

1. Cellular elements 2. Electrolytes 3.Organic compounds 4.Metabolic & bacterial products 5.Enzymes

Functions of Gingival (Crevicular) Fluid

■ Its flow washes out irritants & prevent bacterial penetration. ■ Its plasma proteins improve epithelial adhesion to the teeth. ■ Has antibacterial effect upon many oral microorganisms. ■ Has defense mechanism by its immunoglobulin contents. ■ Essential growth factor for many microorganisms

Cells of the gingival epithelium

Keratinocytes

Non keratinocytes:

Melanocytes Langerhans cells Merkel cells

Keratinized stratified squamous epithelium arranged in 4 layers:

Stratum basale, Basal cell layer (The deepest) Stratum Spinosum, prickle cell laye Stratum granulosum, granular cell layer Stratum corneum, Keratinized cell layer

Lines the gingival sulcus facing the tooth extending from coronal limit of junctional epitht. the crest of gingival margin

Sulcular Epithelium

The tissue that joins the tooth on one side and to sulcular epith& C.T on the otherIt forms the base of the sulcus

Junctional Epithelium (Epithelial attachment)

Attachment of the junctional epith. to the tooth is reinforced by the

Gingival fibers

The junctional epith. and the gingival fibers are considered a functional unit, referred to as the

Dentogingival unit.

Three zones in junctional epith. have been described

Apical, coronal and middle

Lamina propria consist of:

■mainly Collagen fibers (60%) ■ Cells mainly fibroblasts(5%) ■Intercellular ground substance ■Blood vessels, lymphatic, Nerves

Primary gingival fibers:

Circular fibers: Dentogingival fibers: Alveologingival fibers: Dentoperiosteal fibers: Transseptal fibers:

Secondary Gingival Fibers

Semicircular fibers (SCF): from mesial surface of a tooth to distal surface of same tooth in a half circle Transgingival fibers (TGF): these fibers traversing from CEJ to free gingiva of adjacent tooth Intergingival fibers (IGF): extend along facial and lingual marginal gingiva from tooth to tooth.

They are the predominant cells, they are functioning to: 1.Synthesize and secrete collagen fibers, elastin, non-collagenous proteins, glycoprotein 2. Renewal of collagen fibers and other constituents 3. Regulation of gingival wound healing.

Fibroblast

Nerve supply of the gingiva

Maxillary and mandibular branches of trigeminal nerve.

Average width of PDL space is about

0.25mm

The most important elements of PDL are the

Principal fibers type I collagen

Considered remnants of the Hertwig root sheath, which disintegrates during root development.

The epithelial rests of Malassez

Immune system cells:

Neutrophils,lymphocytes, macrophages, mast cells & cosinophils.

Functions of PDL

1. Provision of a soft-tissue "casing" to protect the vessels & nerves from injury by mechanical forces 2. Transmission of occlusal forces to the bone 3. Attachment of the teeth to the bone 4. Maintenance of the gingival tissues in their proper relationship to the teeth 5. Resistance to the impact of occlusal forces (shock absorption

Application of large forces results in _____ of PDL & alveolar bone

Necrosis

Calcified avascular tissue that forms the outer covering of the root of the teeth & provide attachment to the periodontal ligament

Cementum

Has no vascular or nerve connection.

Cementum

Functions of cementum

Provide anchorage, maintaining occlusal relationships

Occurs in Paget's disease

Hypercementosis

Are globular calcified masses adherent to or detached from the root surface.

Cementicles