1. THE PRINCIPAL GROUP FIBERS
1.1. Dentogingival Fibers
1.1.1. Fan-like
1.1.2. Attach gingiva to tooth
1.2. Alveolar Gingival Fibers
1.2.1. From periosteum to lamina propria
1.2.2. Attach gingiva to alveolar bone
1.3. Dentoperiosteal Fibers
1.3.1. From the cementum, inserts into the periosteum of the alveolar bone, and protects the PDL
1.4. Circular Fibers
1.4.1. Surrounds teeth for stability
1.5. Transseptal Fibers
1.5.1. Located Interproximally
1.5.2. Connects cementum of neighboring teeth
1.5.3. Protects the interproximal bone and maintain tooth-to-tooth contact
2. THE SECONDARY GROUP FIBERS
2.1. Periosteogingival Fibers
2.2. Interpapillary Fibers
2.3. Transgingival Fibers
2.4. Circular and Semicircular Fibers
2.5. Transseptal Fibers
2.6. Intercircular FIbers
2.7. Intergingival Fibers
3. PERIODONTAL LIGAMENT
3.1. Categories:
3.1.1. Progenitor Cells
3.1.1.1. Mitotic Division
3.1.2. Synthetic Cells
3.1.2.1. Osteoblasts
3.1.2.1.1. Bone-forming cells
3.1.2.2. Fibroblasts
3.1.2.2.1. Synthesize collagen
3.1.2.2.2. Synthesize fibrils
3.1.2.2.3. Organize fibrous network and generates force for tooth eruption
3.1.2.2.4. Produce extracellular matrix of PDL
3.1.2.3. Cementoblasts
3.1.2.3.1. Cement-forming cells
3.1.3. Resorptive Cells
3.1.3.1. Osteoclasts
3.1.3.1.1. Howship's Lacunae
3.1.3.2. Cementoclasts
3.1.4. Defence Cells
3.1.4.1. Macrophages
3.1.4.1.1. 4% of PDL cells
3.1.4.1.2. Responsible for phagocytosing particulate and invading microorganisms
3.1.4.2. Mast Cells
3.1.4.2.1. Blood vessels
3.1.4.2.2. Heparin, Histamine, etc.
3.1.4.3. Eosinophils
3.1.4.3.1. Normal PDL
3.1.4.3.2. Phagocytosis
3.1.5. Epithelial Cells
3.1.5.1. No clear function
3.1.5.2. Periodontal repair and regeneration
3.1.5.3. Apical and Cervical areas
3.1.5.4. They undergo calcification to become CEMENTICLES
3.2. Extracellular Components:
3.2.1. Fibers
3.2.1.1. Type I (< 70%) and Type III
3.2.2. Ground Substance
3.2.2.1. FIBRONECTIN
3.2.2.1.1. The attachment of cells to the substratum especially to collagen
3.2.2.2. TENASCIN
3.2.2.2.1. a.k.a Cytotactin
3.2.2.2.2. It is found mostly in healing wounds
3.2.2.3. LAMININ
3.2.2.3.1. A major glycoprotein component of basement membrane of epithelial cell rest of malassez
3.2.2.3.2. Functions
4. THE PRINCIPAL FIBERS
4.1. `Denser than interstitial fibers
4.2. Runs from the cementum to the bone
4.3. a.k.a. Sharpey's Fibers (when they are inserted into the alveolar bone and cementum)
5. THE INTERSTITIAL FIBERS
5.1. Randomly arranged throughout the PDL and support the nerves and blood vessels
6. CEMENTUM
6.1. Avascular and not innervated
6.2. Acellular
6.3. Cementocytes
6.3.1. Each cementocyte lies in its Lacuna.
6.4. When exposed through gingival recession:
6.4.1. Abrasion by mechanical friction
6.4.2. Extrinsic staining and dentinal hypersensitivity
7. CELLULAR ELEMENTS
7.1. Cementoblast
7.1.1. Cellular and Acellular cementum
7.2. Cementocyte
7.2.1. Found only in cellular cementum
7.2.2. Located between spaces (lacunae)
7.3. Fibroblast
7.3.1. Belongs to the PDL
7.3.2. Responsible for synthesis of principal fibers
7.3.3. Indirectly participate in the formation of cementum
7.4. Cementoclast
7.4.1. Extensive root resorption that leads to primary teeth exfoliation
7.4.1.1. Reversal Line
7.4.1.1.1. Deeply staining irregular line
7.4.1.2. Trauma from occlusion
7.4.1.2.1. `Forces of the periodontium that produces injury
8. ALVEOLAR BONE
8.1. Cells consists of:
8.1.1. Osteoblasts
8.1.2. Osteoclasts
8.1.3. Osteocytes
8.2. Extracellular matrix consists of 65% inorganic and 35% organic matter
9. COMPACT BONE
9.1. Parallel lamellae
9.2. Haversian System
10. GINGIVAL EPITHELIUM
10.1. Divided into:
10.1.1. Oral
10.1.1.1. Covers the crest and outer surface of the marginal gingiva and attached gingiva
10.1.1.2. Keratinized or parakeratinized
10.1.1.2.1. Areas
10.1.1.2.2. Layers
10.1.1.3. Has a wavy interface
10.1.2. Sulcular
10.1.2.1. Epithelial lining of the gingival sulcus
10.1.2.2. Nonkeratinized
10.1.2.3. Permeable
10.1.2.4. No epithelial ridges
10.1.3. Junctional
10.1.3.1. Proliferative Cell Layer
10.1.3.1.1. In contact with the connective tissue
10.1.3.2. Desquamation (shedding)
10.1.3.2.1. Located at coronal end; forms the bottom of the GS
10.1.3.3. External Basal Lamina
10.1.3.3.1. Facing the gingival connective tissue
10.1.3.4. Internal Basal Lamina
10.1.3.4.1. DAT cells (Directly Attached to the Tooth)
10.2. Functions:
10.2.1. Mechanical, Chemical, Water, Microbial Barrier
10.2.2. Signaling functions for repair and immunity
10.3. Architectural Integrity
10.3.1. Cell-cell attachments
10.3.1.1. Cell Junctions
10.3.1.1.1. Tight
10.3.1.1.2. Adherens
10.3.1.1.3. Desmosome
10.3.1.1.4. Gap
10.3.1.1.5. Hemidesmosome
10.3.1.2. Holds cells together
10.3.2. Basal Lamina
10.3.3. Keratin cytoskeleton
11. KERATINOCYTE
11.1. Principal cell type of the GE
12. NON-KERATINIZED/CLEAR CELLS
12.1. Melanocyte
12.2. Langherhans Cells
12.3. Merkel Cells
12.4. Lymphocytes
13. GINGIVAL CONNECTIVE TISSUE
13.1. Consists of:
13.1.1. Cells, Fibers, Blood vessels
13.2. Major components:
13.2.1. Collagen Fibers
13.2.2. Fibroblasts
13.2.2.1. 5%
13.2.3. Vessels, Nerves, Matrix
13.2.3.1. 35%
14. GINGIVAL FIBERS
14.1. Type I (can also include Type III fibers)
14.2. Functions
14.2.1. Stability
14.2.2. Rigidity
14.2.3. Connection
15. PDL FIBER BUNDLES
15.1. Alveolar crest
15.2. Horizontal
15.3. Oblique
15.4. Interradicular
15.5. Apical Fibers
16. FIBROUS ELEMENTS
16.1. 2 types:
16.1.1. Extrinsic Fibers (Sharpey's Fibers)
16.1.1.1. The embedded portion of the principal fibers of the PDL and are formed by the fibroblast cells.
16.1.1.2. Inserted at right angles to the root surface and penetrate deep into the cementum
16.1.2. Intrinsic Fibers
16.1.2.1. Produced by cementoblasts
16.1.2.2. Parallel to the long axis of the root
16.1.2.3. Forms a cross-banding arrangement with sharpey's fibers
17. INTERFIBRILLAR MATRIX
17.1. Proteoglycans, glycoproteins, and phosphoproteins
17.1.1. Proteoglycans plays a role in cell-cell and cell matrix