018.defense mechanisms of gingiva

Dr Jaffar Raza Syed Page 1

Defense Mechanisms of Gingiva

Various defense mechanisms of oral cavity

(i) Saliva

(ii) Sulcular fluid (GCF)

(iii) Intact epithelial barrier + Basement membrane

(iv) High tissue turnover

(v) Presence of normal flora (Bacterial balance)

(vi) Local antibody production

(vii) Migrating PMNs and other leukocytes


--Imbalance of the host-microbial relationship is occurring in the destructive lesions Normal gingiva VS clinical healthy gingiva

--Pink color, firm consistency and scalloped outline for gingival margin. --The interdental papillae are firm, do not bleed on gentle probing and fill the space below the contact areas. --Can only be established experimentally after supervised meticulous daily plaque control for several weeks --The gingivae we would routinely classify as "clinically healthy gingivae" are not as histological perfect as the "normal gingivae“ --Clinically healthy gingivae would be typically that level of health which could be attained by patients regularly practicing a good standard of plaque control.


Sulcular fluid = Gingival creivicular fluid (GCF) --firstly discovered at 1950s. --In normal gingiva called transudate --In disease gingiva called inflammatory exudates Phagocytosis By PMNLs and macrophages Aided by complement C3, C4 and C5 cleavage C3a, C4a and C5a C3a, C4a and C5a anaphylotoxins

--they can induce smooth muscle contraction,

--increase permeability of blood vessels

--causes the release of histamine from mast cells and basophils

C5a chemotactic for neutrophils and monocytes


Inflammatory Reaction

changes in the local microcirculation hyperemia

increased vascular permeability

formation of a fluid and cellular exudate


composition of saliva A. Electrolytes:

(a) Potassium

(b) Sodium

(c) Chloride

(d) Bicarbonate

(e) Calcium

(f) Magnesium

(g) Phosphorous


B. Organic: (i) Acinar cell families: • Mucin • Proline rich proteins and glycoproteins • Histatins and statherins • Cystatins • Amylase • Peroxidases • Carbonic anhydrases (ii) Ductal and stromal products: • Lactoferrin • Lysozyme • Secretory IgA • Kallikrein • Fibronectin • Lipids • Carbohydrates • Sulfates


Composition of GCF A. Cellular elements:

(i) Epithelial cells

(ii) Leukocytes

(iii) Bacteria

B. Electrolytes:

(i) Sodium

(ii) Potassium

(iii) Calcium

C. Organic compounds:

(i) Carbohydrates

(ii) Proteins

• Immunoglobulins

• Complement components

(iii) Lipids


D. Metabolic and bacterial products:

(i) Lactic acid

(ii) Hydroxyproline

(iii) Prostaglandins

(vi) Urea

(v) Endotoxins

(vi) Cytotoxic substances

(vii) Antibacterial factors


E. Enzymes and enzyme inhibitors:

(i) Acid phosphatase

(ii) Alkaline phosphatase

(iii) Pyrophosphatase

(iv) β - glucuronidase

(v) Lysozymes

(vi) Hyaluronidase

(vii) Proteolytic enzymes

• Mammalian proteinases

• Bacterial proteinases

• Serum proteinases inhibitors

(viii) Lactate dehydrogenase.

Dr Jaffar Raza Syed

Methods of collection of GCF (i) Absorbing paper strip

(a) Intracrevicular

(b) Extracrevicular

(ii) Preweighed twisted threads

(iii) Sampling by means of micropipettes

(iv) Gingival washings

(v) Other strips

(a) Plastic strips

(b) Platinum loops

ethods of collection of GCF

(iii) Sampling by means of micropipettes

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Dr Jaffar Raza Syed

How the amount of GCF collected is evaluated (i) By direct viewing and staining Stain the strip with ninhydrin

(ii) By weighing:

Strip is weighed before and after collecting the GCF

(iii) By electronic device Periotron:

Sample strip paper is inserted on the screen.

How the amount of GCF collected is evaluated

nd staining: ninhydrin and then measured.

Strip is weighed before and after collecting the GCF sample.

By electronic device Periotron:

Sample strip paper is inserted between the two jaws, which gives reading

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between the two jaws, which gives reading


Problems associated with GCF collection and data interpretation (i) Contamination Usually sample is contaminated with blood, saliva or plaque. (ii) Small sample size. (iii) Sampling time Prolonged sampling at the site results in protein concentrations approaching those of serum. (iv) Volume determination Evaporation is a significant problem in accurate volume determination of GCF (v) Recovery of strips It depends on type of paper, binding of GCF protein to the filter paper and concentration of the original protein sample.


Volume of gingival fluid The mean gingival fluid molar teeth 0.43 to 1.56 μl anterior teeth 0.24 to 0.43 μl Collective calculated amount 0.5 to 2.4 μl of fluid/day


Clinical Significance General Health and Gingival Fluid Gingival fluid flow and sex hormones --Menstruation Increase --birth control pills Increase --pregnancy Increase (max values in last trimester) --Gingival fluid flow and Diabetes higher production of gingival fluid due to increase in width of the basal membrane of capillaries, small arteries and venules.

Health & Medicine

018.defense mechanisms of gingiva