Junctional Epithelium / Epithelial Attachment - PowerPoint PPT Presentation

1 / 14
About This Presentation
Title:

Junctional Epithelium / Epithelial Attachment

Description:

Cuticle also seen between JE and underlying cementum. Length of Junctional Epithelium ... eruption or disease) JE proliferates apically - firm attachment with cementum ... – PowerPoint PPT presentation

Number of Views:2649
Avg rating:3.0/5.0
Slides: 15
Provided by: ajsc
Category:

less

Transcript and Presenter's Notes

Title: Junctional Epithelium / Epithelial Attachment


1
Junctional Epithelium / Epithelial Attachment
  • What and where it is
  • Where it comes from
  • What it does
  • Why it does it

2
What and Where is the Junctional Epithelium
  • Epithelial attachment and clinical attachment
    level
  • Collar-like band of nonkeratinised stratified
    squamous epithelium
  • Extends from cementoenamel junction - bottom of
    gingival sulcus
  • Coronally 15-30 cells thick. Apically narrows
    to 1-3 cells
  • Length 0.25 1.35mm has rate of turnover

3
A- gingiva B- sulcular epithelium C- junctional
epithelium D- lamina propria (connective
tissue) E- alveolar process F- PDL
ES- enamel space JE junctional epithelium CT-
connective tissue
4
Where does it come from ?
  • Initially derived from Reduced Enamel Epithelium
  • REE replaced once tooth erupts REE covering
    crown lost rapidly replaced by squamous
    epithelial cells
  • Transformed REE oral epithelium form
    dentogingival junction and junctional epithelium
  • Final conversion of REE to JE may not occur until
    3-4 years post eruption

5
Important Features
  • Cells of JE immediately adjacent to tooth attach
    to tooth by hemidesmosomes basal lamina
  • Combination is known as the epithelial attachment
  • Basal lamina in contact with tooth Internal
    Basal lamina
  • On opposite surface JE in contact with lamina
    propria of gingiva attached by hemidesmosomes
    and basal lamina
  • Basal lamina in contact with lamina propria
    External Basal Lamina

6
Junctional epithelium is unique as it possess 2
basement membranes the internal and external
basal lamina
Enamel
Lamina propria
Hemidesmosomes
Internal Basal Lamina
External Basal Lamina
7
JE
CT
External basal lamina
Enamel space
Internal basal lamina
8
Enamel Cuticle
  • Not visible in demineralised sections
  • Non-mineralised structure between JE and
    underlying hard tissue
  • Cuticle also seen between JE and underlying
    cementum

9
Length of Junctional Epithelium
  • Length varies according to stage of eruption
  • Tooth first erupts most of enamel covered by JE
  • Tooth reaches occlusal plane ¼ enamel surface
    covered
  • Eventually JE lies close to CE junction
  • Older patients with root exposure (passive
    eruption or disease) JE proliferates apically -
    firm attachment with cementum

10
Other Fantastic Facts You Really Wanted to Know
About the Junctional Epithelium!!!!
  • Lamina propria of gingiva good vaculature and
    source of nutrient to JE and source of GCF
  • JE is permeable tissue fluid and cells pass
    into GCF
  • Turnover of JE is rapid. Epithelial cells migrate
    coronally shed into oral cavity via gingival
    crevice
  • Rate of turnover dependent on demands placed on
    tissue. Directly related to degree of inflammation

11
What it does and why it does it
  • Has attachment role and protective role
  • Permeability allows GCF and defence cells to
    pass across to protect underlying tissues from
    disease processes (periodonal disease)
  • Helps maintain integrity of tooth / periodontium
    structure.

12
Role of JE Clincial significance
  • GCF contains g globulins and ploymorphonucleocytes
    (PNMs) giving it immunological / phagocytic
    properties to combat disease processes
  • Such molecules pass readily across JE to
    underlying tissues
  • JE ( GCF) good indicator for severity of
    periodontal disease may contain neutrophils
    other inflammatory cells indicating disease
    state of health of periodontium
  • Research into this ongoing in Bham
    understanding progression of disease
    development of diagnostic marker of severity of
    disease

13
(No Transcript)
14
Reason why I have not been around for the past 2
weeks!!
Write a Comment
User Comments (0)
About PowerShow.com