Defence Mechanism Of Oral Cavity

1. Defence
mechanism
of
gingiva
Dr. Abhishek Gaur
BDS, MDS, F.A.G.E., (Ph.D.)
Periodontist & Oral Implantologist
Defence
mechanism
of
gingiva
Dr. Abhishek Gaur
BDS, MDS, F.A.G.E., (Ph.D.)
Periodontist & Oral Implantologist

2. Gingival Tissues
Constantly subjected to mechanical
trauma and bacterial aggression.
Saliva,Epithelial surface and
inflammatory response provide
resistance to these actions

3. Gingival Sulcular Fluid
Inflammatory Exudate.
Has been known since 19th century.
Composition and role in periodontal disease has been elucidated by
pioneering work of Brill & Krasse in 1950.
Filter paper in the sulcus of animals previously injected im with
fluorescein; within 3 minutes the fluorescent from the filter paper

4. Methods of Collection
of
GCF
1. Absorbing paper strips
2. Twisted threads
3. Micropipettes
4. Intracrevicular Washings

6. Showing Perio-tron measuring
amount of GCF collected

7. Composition
More than 40 compounds from GCF have been analysed but their origin is not
known with certainty.
They can be derived from host, bacteria like Collagenases (MMPs), β-
glucouronidases.
Cellular elements:
Bacteria, Desquamated epithelial cells and leukocytes(PMN’s, Lymphocytes,
Monocytes/ macrophages)
Electrolytes:
K, Na and Ca have been studied in GCF.
Positive correlation of Ca and Na conc. and Na/K ratio with inflammation

8. Organic
Compounds
1. Glucose hexosamine and hexuronic acid are two
compounds found in GCF.
2. Blood glucose is 3-4 times greater than serum.
3. Total protein content is much less than serum.

9. Clinical Significance
GCF is inflammatory exudate and positively correlates with
amount and severity of inflammation.
GCF flow is increased by Mastication, coarse food,
toothbrushing, gingival massage, Ovulation, Hormonal
contraceptives and smoking.
GCF secretion follows circadian periodicity increases 6 am to
10 pm than decreases afterwards.
Female sex hormone increase GCF flow as they enhance
vascular permeability.

10. Mechanical stimulation like chewing and
vigorous tooth brushing increases GCF flow.
Smoking causes immediate transient but marked
increase in GCF flow.
There is increase in GCF production during
healing period following periodontal surgery.

11. Drugs in GCF
Tetracycline
Metronidazole

12. SalivaSaliva

13. Saliva
It’s a physiologic secretion by various major and minor
salivary glands.
It’s has got certain major functions like mechanical cleansing,
lubricating and buffering actions.
It has got antibacterial property as well.

14. Anti-Bacterial Factors
Can be divided into :
1. Inorganic factor
2. Organic factor

15. 1. Inorganic factors :
Includes ions and gases like Bicarbonate, Na, k, Phosphate, Ca, Ammonium, and Carbon
dioxide
2. Organic factors :
Includes enzymes like :
Lysozyme: Hydrolytic enzyme that cleaves the linkages of cell wall of both
Gm +ve and Gm –ve bacteria.
Targets Veillonella and A.a.
Lactoperoxide - thiocyanate system:
Bactericidal to Lactobacillus and
Streptococcus by preventing accumulation of lysine and glutamic acid essential for their
growth.

16. Salivary Enzymes
Following Enzymes are increased in periodontal disease :
1. Hyaluronidase
2. β-glucouronidase
3. Chondroitin sulfate
4. Aspartate aminotransferase
5. Alkaline phosphatase
6. Amino acid de-carboxylases, Catalase, Peroxidase and Collagenases.

17. Salivary
Buffers
Bicarbonate-carbonic acid

18. Coagulation
Factors
Factors VIII, IX and X,
Factor XI (Plasma thromboplastin antecedent)

19. Role in Periodontal
Pathology
Saliva effects plaque initiation, maturation and metabolism.
Salivary flow and composition also influences calculus
formation, periodontal disease and dental caries.

20. There is increase in prevalence and severity of
periodontal disease as a consequence of reduced
salivary flow in :
1. Mikulicz’s disease,
2. Sjogren’s syndrome,
3. Sialothiasis,
4. Sarcoidosis
5. Xerostomia following radiotherapy