1.Gingiva- The tissue that covers the cervical portions of the teeth & the alveolar bone.

2. PDL- The fibers that surround the tooth root; they attach to the bone of the socket on 1 side & to the root cementum on the other side.  

3. Cementum- Thin layer of mineralized tissue that covers the tooth root.

4. Alveolar Bone- Bone that surrounds the tooth rooths.  It forms the bony sockets that support & protect the tooth roots.

• Provides a tissue seal around the cervical part of tooth
• Holds tissue against tooth during mastication
• Made of a thin outer layer of epithelium and an underlying core of connective tissue

1. Suspends & maintains the tooth in the socket.

Provides pressure & pain sensory feeling to the tooth.

3. Provides nutrients to the cementum & bone.

4. Builds & maintains the cementum & alveolar bone of the tooth socket.

5. Remodels the alveolar bone in response to pressure.  

• Anchors the ends of the PDL fivers to the tooth so that the tooth stays in its socket
• Protects the dentin of the root

• Located coronal to the CEJ
• Surrounds tooth like a turtleneck
• Fits snugly around tooth but isn't attached
• Can be gently pulled away from the tooth with a probe
• Forms soft tissue wall of the gingival sulcus
• Meets the tooth in a thin rounded edge called the Gingival Margin
• Margin of the free gingiva follows the tooth contours, creating a wavy outline. 

• The space between free gingiva & tooth surf.
• Sulcus base is formed by Jxnl Epi.
• Depth of clinically normal sulcus is 1-3mm

The portion of gingiva that fills the area between 2 adj teeth apical to the contact area.

• Made of 2 interdental papillae (facial & lingual)
• Col is a valleylike depression in the indertental gingiva that lies directly apical to the contact area
• Col is absent if teeth are missing/recession is present.

Attached Gingiva 

Card 1

-Located between the free gingiva & the alveolar mucosa.
-Widest in the incisor & molar reigons

-Narrowest in premolar reigons
-Lingual gingiva is contionous w/ palatal mucosa
-AG isn't measured on palate bc it's difficult to destinguish it from palatal mucosa.
-Color is pale or coral pink; may be pigmented.
-Pigmentation is more freq in dark skinned individuals
-Color of pigmentation ranges from light brown-black.

Attached Gingiva

Card 2

-AG surface may have dimpled appearance like an orange peel; aka stippling

- Stippling is caused by connective tiss. fibers that attach the gingival tissue to cementum & bone.

-AG prevents free gingiva from being pulled away from the tooth when tension is applied to the alveolar mucosa.

-Allows gingival tissue to withstand mechanical forces created during chewing, speaking & toothbrushing.

- Thin layer of hard mineralized tissue that covers root surface.

-Light Yellow

-Overlies dentin

-Bonelike but more resistant to resorption than bone

- Doesn't have it's own blood/nutrient supply

- Surrounds & supports the tooth roots in the jaws.

- Existance of AB is dependant on the presense of teeth. 

-EXT's lead to resorbption of alveolar bone around the missing tooth.

1. Alveolar Bone Proper (Cribiform Plate)

2. Cortical Bone

3. Concellous Bone (Spongy Bone)

4. Periosteum

Alveolus- Bony socket that houses the tooth root

- Appears to have large pores where blood vessels connect structures

-Ends of PDL fibers are embedded in ABP

-Forms the hard outer wall of the jaws on the FACIAL and LINGUAL aspects

- Surrounds the ABP & gives support to the socket

- Doesn't show up on radiographs

- Alveolar crest most coronal portion of the cortical bone. 

- Spongy, latticelike bone filler bet. the cortical bone and ABP.

- Oriented around the tooth to form support for the ABP.

- Layer of connective soft tissue covering the outer surface of bone.

- Made of an outer layer of collagenous tissue and inner layer of fine elastic fibers.  

It is the rich supply of blood to gingiva that accounts for color changes seen in gingivitis.  

- Starts with ECA (External Carotid Artery)

- Max. Artery is a branch of the ECA

- All other arteries that supply the periodontium of both max & mand teeth are branches of the Max Artery.

Major Arteries (Branches of the Max. Artery)

1. Superior Alveolar Arteries

-Maxillary periodontal tissues

2. Inferior Alveolar Artery

- Mandibular periodontal tissues

Maxillary gingiva, PDL, & Alveolar Bone

- Anterior & Posterior Superior Alveolar Arteries

- Infraorbital Artery

-Greater Palantine Artery

-ALL of these are branches of the maxillary artery *not sure about last bullet

Vascular Supply to Periodontium Mandible

Mandibular Gingiva, PDL, & Alveolar Bone

-Inferior Alveolar Artery

-Branches of Inferior Alveolar Artery

(Buccal, facial, mental, & sublingual Arteries)

-All are branches of the maxillary artery

* Not sure about last bullet

Vascular Supply to Teeth & Periodontal Tissues

(7 parts)

Branch Arteries (see P 16 Part B)

1. Dental Artery

-Branch of superior/inferior alveolar artery

-Supplies the individual teeth

2. Interseptal Artery

-Bone Marrow Spaces between Teeth

3. Rami Perforantes

-Terminal branches of intraseptal artery enter tooth socket, go into PDL space, & anastomose vessels from bone & ligament  

4. Supraperiostal Blood Vessels

-In free gingiva, anastomose w/ vessels from bone & ligament

5. Subepithelial plexus

-Branches of supraperiostal vessels found in connective tissue under attached gingiva.

6. PDL vessels

-Supply PDL, form complex network of vessels surrounding roots.

7. Dentogingival Plexus

- Network of vessels found in connective tissue under gingival sulcus.                               

1. Epithelial Tissue- Makes up the outer surface of the body & lines the body cavities such as the mouth, stomach & intestines.

2. Connective Tissue- Fills the space between the tissues & organs in the body.

• Cells- The smallest unit of living matter
• Extracellular matrix- Gel-like substance containing protien fibers

-Makes up the outer surface of the body (skin)

-Lines the body cavities such as the mouth, stomach, & intestines

- Characterized by PLENTIFUL CELLS, sparse extracellular matrix

Cells

- Plentiful Cells

- Epithelial tissue is made mostly of closely packed cells

- In epithelial tissue, the thin mat of extracellular tissue is called the basal lamina

Keratinization of Epithelial Tissue

Keratinization- The process by which epithelial cells on the skin surface become stronger and waterproof

Keratinized Epithelial Cells...

- Have no nuclei 

- Form a tough, resistant layer on the skin surface

- The soles of the feet are the most heavily keratinized area of the body

- Have nuclei

- Act as a cushion against stress & wear of the tissue

- Are softer & more flexible then keratinized cells

- The lining of the cheeks is nonkeratinized; permitting the mobility needed to speak, chew, & make facial expressions

- Epithelial tissues contain no blood vessels

- Nourishment is recieved from blood vessels contained in the underlying connective tissue

- Cartilage

- Bone & Bone Marrow

- Tonsils & Lymph Nodes

- Fat

- All dental tissues- cememtum, dentin, pulp- are forms of connective tissue except the enamel. The enamel is an epithelial tissue (this is REALLY important!)

- A rich, gel-like substance containing a network of strong fibers

- The fibers, rather than the cells, give connective tissue its strength

- The connective tissue has a rich blood supply that brings nourishment to both the connective tissue, itself, and also to the epithelial tissue that covers it

(Gives mouth its pink color)

- Epithelial tissue is made of many cells

How do these epithelial cells stick together?

- Cell junctions

Cell junction- Cellular structures that mechanically attach a cell to either (1) it's neighboring cell or (2) the basal lamina layer

- Purpose: To bind cells together so that they can function as a strong structural unit (ie skin)

Desmosome (Cell jxn #1)- Connects 2 neighboring epithelial cells together; a cell-to-cell connection.

Hemidesmosome (Cell jxn #2)- Connects epithelial cells to the basal lamina layer; a cell-to-basal lamina connection

- Important form of cell junction in the gingival epithelium

Epithelial-Connective Tissue Boundary

OR

How the Cells Meet

- The epithelial & connective tissue may meet in either a wavy or smooth boundary

- In most places in the body, these tissues meet in an uneven, wavy boundary

Epithelial ridges & Connective Tissue Papillae

Terminology

- Epithelial ridges- Extensions of the epithelium that reach down to connective tissue

- Connective tissue papillae- Fingerlike extensions of the connective tissue that extend up into the epithelium

- Enhances the adhesion of the epithelium to the connective tissue by increasing the surface area at the boundary where these 2 tissues meet

- The wavy boundary increases nourishment to the epithelium

- The wavy junction increases the area from which the epithelium can recieve nourishment from the connective tissue

(Remember the epithelium doesn't have blood vessels)

- Oral epithelium- Covers the free & attached gingiva

- Sulcular epithelium- Lines the sulcus

- Junctional Epithelium- A dense network of collagen fibers tightly anchors the epithelium

- Epithelial lining of the gingival sulcus

- Thin, nonkeratinized epithelium; making it less resistant to stresses

- Smooth boundary (in health)

- SE is permable, allowing fluid to flow from the gingival connective tissue into the sulcus- gingival crevicular fluid                   

- Epithelium that forms the tissue of the sulcus

- Epithelium that joins the gingiva to the tooth

- Length - 0.71 to 1.35 mm

- 15-30 cells thick at the coronal zone

- 4 to 5 cells thick at the apical zone

- The epithelial cells of both the sulcular and the junctional epithelium are nonkeratininzed and the boundary, when healthy, is smooth!

- These areas of the epithelium provide the easiest point of entry for bacteria to invade the underlying connective tissue.

- A continous sheet of epithelium protects the body.

- This sheet covers all the body's outer surfaces and lines the body cavities.

- This epithelial covering creates a barrier to stop bacteria & viruses from entering the body.

- When a tooth erupts, it penetrates...punches thru... the oral epithelium.

 - Tooth eruption creates an opening in the epithelial sheet through which microorganisms could enter the body... like an open door.  Oops!  That is why...

- The body attempts to seal the opening created by the erupted tooth by attaching the gingival epithelium to the tooth via the junctional epithelium. 

- The word 'junction' means connection

- Thus, the epithelium that is connected to the tooth is called the junctional epithelium.

- The JE attaches the gingiva to the enamel and/or the cementum of the tooth.

- Because of this attachment, the JE provides a seal at the base of the gingival sulcus or periodontal sulcus.

- The JE provides a protective barrier between the plaque biofilm & the underlying connective tissue of the periodontium. 

- Like other epithelial tissues of the body, the junctional epithelium has plentiful cells.

- These cells are held together by cell junctions just like other areas of epithelium in the body.

- Junctional Epithelial cells attach to the tooth using

• Hemidesmosomes
• Internal basal lamina

The JE cells attach to the underlying connective tissue using

• Hemidesmosomes
• External basal lamina

- Provides solidity to the gingiva

- Attaches gingiva to the cementum of the root and the alveolar bone

- The gingival connective tissue has an abundant extracellular matrix

- Protien fibers make up about 55-65% of the gingival connective tissue

- Fibers form a dense network of strong, ropelike cables that hold the connective tissue together. 

- Brace the free gingiva firmly against the tooth

- Reinforce attachment of the JE to the tooth

- Provide rigidity to withstand chewing

- Unite free gingiva with the cementum of the root & bone

- Connect adjacent teeth to each other

The JE+the gingival fibers=the dentogingival unit

- The dentogingival unit provides structural support to the gingival tissues.

-Cells

• Fibroblasts
• Cementoblasts
• Osteoblasts

- Extracellular Matrix

- Blood Vessels

- Nerve supply

*Remember the PDL is connective tissue!

1.  Supportive function- Attaches the tooth to the bony socket & suspends the tooth.
2. Sensory function- Transmits tactile pressure & pain sensations.
3. Nutritive Function- Has blood vessels that provide nutrients to the cementum & bone.
4. Formative function- Contains cementoblasts that produce the cementum throughout the life of the tooth.
5. Resorptive function- Contains osteoclasts that can resorb the bone & the cementum.

- Alveolar Crest Fibers- Resists horizontal tooth movements; extend from the cervical cementum, running downward diagonally to the alveolar crest.

- Horizontal Fibers- Resists horizontal pressure against tooth crown; extend from cementum to the bone @ R angles to the long axis of root. Apical to AC fibers.

- Oblique Fibers- Resists vertical pressures that threaten to drive the root into its socket.  Apical to H fibers.

- Apical Fibers- Secures the tooth in its socket & resists forces that may lift the tooth out of the socket.  Extends from tooth apex to bone.

- Interradicular Fibers- (found only in multirooted teeth) Help stabilize tooth in socket.  Extend from cementum in furcation area to the interradicular septum of the alveolar bone.

- Fine collagen fibers arise from the cementum & the alveolar bone proper.

- Fibers grow into the midportion of the PDL.

- Fibers from the root cementum fuse w/ the fibers from the alveolar bone proper.

- Ends of PDL fibers that are embedded in the cementum & the alveolar bone.

- Attachment of the fiber bundles occurs when the cementum & the bone are forming.

- As the cementum forms, it hardens around the ends of sharpey's fibers, surrounding them w/ the cementum.

- As the albeolar bone forms, it, too, surrounds the opposite ends of the sharpey's fibers.

- Calcified layer of connective tissue that covers the tooth root.

- A thin layer of cementum (blue band) covers the dentin of the root.

- The periodontal ligament holds the tooth in the bony socket of the alveolar bone.

- Seals & covers open dentinal tubules

- Acts to protect the underlying dentin

- Attaches periodontal fibers to the tooth

- Forms @ apical areas of roots to compensate for the loss of the tooth tissue caused by attrition.

- Organic matrix portion

* Densely packed collagen fibers held together w/ gel matrix

- Mineralized portion

- No blood vessels or nerves

* 2 types:

Cellular & Acellular

- Contains no cementocytes within the mineralized tissue

- 1st to be formed

- Covers the cervical 1/3 or 1/2of the root

- Not made during the life of the tooth

- Thickness ranges from 30-60 µm

- Consists of mostly Sharpy fibers

- Contains cementocytes within the mineralized tissue

- Continues to form after the tooth eruption

- Less calcified then the acellular cementum

- Deposited at intervals throughout the life of the tooth

- Thickness ranges from 150 to 200 µm

The cementum may have 1 of 3 relationships with the enamel of the tooth crown.

- Overlap- 60% cementum overlaps the enamel

- Meet- 30% cementum meets the enamel

- Gap- 10% small gap between the cementum & the enamel

* HINT remember OMG

- Alveolar Bone Proper (or 'cribiform plate')

- Trabecular bone (or 'cancellous bone' or 'spongy bone')

- Compact bone (or 'cortical bone')

- Forms the bony sockets of the teeth

- Supports & protects the roots of the teeth

Components:

- Cells

- Osteoblasts & Osteoclasts

- Extracellular Matrix

- Collagen fibers & gel-like matrix

- Mineral portion= Hydroxyapatite

- Vessels & nerves are present in bone

- Bone constantly undergoes periods of formation & resorption