1 / 59

DEFENSE MECHANISM OF GINGIVA

DEFENSE MECHANISM OF GINGIVA. CONTENTS. INTRODUCTION SALIVA Composition Functions Antibacterial factors GCF Methods of collection Measurement of volume Composition Drugs secreted in GCF Clinical Significance Rationale for use of GCF as a diagnostic kit. INTRODUCTION.

kathleenh
Download Presentation

DEFENSE MECHANISM OF GINGIVA

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. DEFENSE MECHANISM OFGINGIVA

  2. CONTENTS • INTRODUCTION • SALIVA Composition Functions Antibacterial factors • GCF Methods of collection Measurement of volume Composition Drugs secreted in GCF • Clinical Significance • Rationale for use of GCF as a diagnostic kit

  3. INTRODUCTION • Defense mechanisms can be roughly divided into • INNATE DEFENSE MECHANISMS • ACQUIRED DEFENSE MECHANISMS.

  4. INNATE DEFENSE • First line, present from birth, genetic constitutional • Not enhanced by prior exposure to an infectious agent • Lacks immunological memory • and Antigenic specificity • ACQUIRED DEFENSE • Not present from birth, specific in nature-against microorganisms. • Natural/artificial and active/passive

  5. The gingival tissue is constantly subjected to mechanical and bacterial aggressions. The Epithelial Surface, Saliva and the Gingival Crevicular Fluid provide resistance to these actions.

  6. NON SPECIFIC HOST DEFENSE MECHANISM Epithelial barrier • Mechanical barrier to bacterial penetration • Protects against mechanical damages like mastication and brushing. • Basement membrane barrier to bacterial penetration

  7. Keratinization • The protection afforded by the epithelium depend to a great extent on keratinization. • Keratin are a group of fibrous protein resistant to hydrolysis and enzymic action. Epithelial renewal • High rate of tissue turnover . • Constant renewal contribute to self cleansing tendency of the sulcular area. • Superficial injuries are repaired by the rapidity of cell turn-over.

  8. SALIVA • Saliva has been defined as “the fluid secreted by the salivary glands that begins the digestion of foods”.

  9. COMPOSITION OF SALIVA • saliva INORGANIC ORGANIC Ions like Na,k,ph, bicarbonates,fluorides, gases like co2

  10. COMPOSITION OF SALIVA • Proteins Small Organic molecules Electrolytes • Albmin Amino acids Ammonia • Amylase Creatinine Bicarbonate • B-glucuronidase Glucose Calcium • Carbohydrates Lipids Chloride • Cystatins Nitrogen Fluoride • Epidermal growth factor Sialic acid Iodine • Esterases Urea Magnesium • Fibronectin Uric acid Phosphates • Gustin Potassium • Histatins Sodium • Immunoglobulin A Sulphates • Immunoglobulin G Thiocyanate • Immunoglobulin M • Kallikrein • Lactoferrin • Lipase • Lactic acid dehydrogenase • Lysosyme • Mucins • Nerve growth factor • Parotid aggregins • Peptidases • Phosphatases • Proline rich proteins • Ribonucleases • Salivary peroxydases • Secretory component • Secretory IgA • Serum protiens

  11. SALIVA • Salivary Flow: • Depends on location of salivary gland&their ducts. • Higher salivary flow low caries incidence. 2.Salivary Buffer • Prevent bacteria colonizing • Plaque microorganism produce acid from sugar if not buffered cause demineralization of enamel. • Bicarbonates and phosphate ions –buffering, • protein has a role in buffering • Urea serves as generated buffer

  12. 3.Salivary pH: 5.6 to 7.0 Avg-6.7 • pH falls during sleep, • enhanced during increased salivary flow rate. • 4.Salivary glycoprotein • Mucin • A.protection against dessication &environment insults like acids and degradative enzymes. • B.lubrication of covered surface. • C.antimicrobial effect.

  13. 5.Salivary antibacterial factors • Inorganic &organic factors influence colonization of bacteria. • A.Lysozyme:hydrolytic enzyme cleaves linkage b/w glycopeptide muramic acid. • Works on both gram +/-. • B.Lactoperoxidase thiocyanate:bactericidal prevents accumulation of lysine&glutamic acid which are essential for bacterial growth. • C.Lactoferrin:bacteriostatic property.depletes iron need for bacterial growth. • D.Myeloperoxidase:bacteriocidal for actinomyces.

  14. 6.Salivary antibodies • IgA is predominant in saliva,IgM. • IgG is predominant in GCF • 7.Salivary Enzymes • Hyaluronidase,lipase,beta-glucornidase,chondrotin sulphatase,catalases,peroxidase&collagenase • Increased in periodontal disease • 8.Coagulation factors • Factor viii,ix,x,xi,xii • Blood coagulation&protect wound from bacterial invasion

  15. Gingival Crevicular Fluid • Known since 19th century.Waerhaug , Brill And Krasse in 1950. • GCF considered as Transudate or a Inflammatory Exudate • In healthy sulcus – less • During inflammation- increases • Passes from CT- EPI- GINGIVAL SULCUS

  16. Gingival sulcus • It’s the shallow Crevice or space around the tooth bounded by surface of the tooth on one side and epithelial lining the margin of the gingiva on the other • V- shaped • Under absolute normal conditions, depth is 0 • - Histological – 1.8mm 1.5mm 0.69mm • Healthy gingiva- clinical depth is 2-3mm

  17. Gingival sulcus/ crevice } FREE GINGIVA ATTACHED GINGIVA

  18. GCF • FUNCTIONS OF GCF • Cleanse material from the sulcus • Contains plasma protein • Possess antimicrobial property • Defense through antibody formation

  19. Method of collection • SAMPLING OF CREVICULAR FLUID BY MEANS OF ABSORBING PAPER STRIPS • TWISTED THREADS • SAMPLING OF GCF BY MEANS OF MICROPIPETTES • GINGIVAL WASHINGS

  20. CAPILLARY TUBE

  21. Gingival washings

  22. MEASUREMENT OF THE VOLUME OF GCF • STAINING • WEIGHING • PERIOTRON

  23. OTHER METHODS Various instruments have been used to obtain samples from crevicular area • PLASTIC STRIPS • TRANSPARENT STRIPS • PLATINUM LOOPS • MICROSPATULES

  24. Methods of estimating the volume collected Appreciation by Direct Viewing or Staining • The amount of GCF collected on a strip was assessed by the distance the fluid had migrated up the strip. • This was often taken as a simple linear measurement, but a more accurate value was achieved by assessing the area of filter paper wetted by the GCF sample. • Further accuracy was achieved by staining the strips with ninhydrin to produce a purple color in the area where GCF had accumulated.

  25. Weighing The Strip • This method involves the weighing of strips before and after sample collection. • This is a successful method but requires a very sensitive balance to estimate the very small amounts of fluid which may be collected from a healthy crevice. • Weinstein et al.(1967) use preweighed twisted thread into the gingival crevice around the tooth and determined the amount of fluid collected.

  26. The Use of Periotron • The introduction of this measuring device, has allowed accurate determination of the GCF volume and subsequent laboratory investigation of the sample composition. • The instrument measures the affect on the electrical current flow of the wetted paper strips. • It has two metal 'jaws' which act as the plates of an electrical condenser.

  27. If a dry strip is placed between the 'jaws', the capacitance is translated via the electrical circuit and registers 'zero' on the digital readout. • A wet strip will increase the capacitance in proportion to the volume of fluid and this can be measured as an increased value in the readout. • The technique is rapid and has no discernible affect upon the GCF sample.

  28. Three models of Periotron have been produced (The 600, 6000 And Now 8000) and each one has been shown to be an efficient means of measuring the volume of fluid collected on filter paper strips. • One of the limitations of the Periotron has been its inability to measure volumes of GCF less than 1.0 µl. • The newer Periotron 8000 has a wider range, particularly if the 'Sialo scale' is used, this being usually reserved for its role as a sialometer.

  29. Problems with GCF collection and data interpretation Contamination • The major sources of contamination of GCF samples would be blood, saliva, or plaque. • The presence of dental plaque on filter paper strips used for collecting GCF has been shown to have a marked effect on the volume recorded. • Careful isolation should be performed in an effort to minimize the potential for saliva contamination.

  30. Sampling time • The filter paper strips should be left in place for 5 seconds . • Alternative technique included leaving the strip in place for a longer period or the use of a sequence of repeated strips, with possible recovery periods in between . • This approach has sometimes resulted in collection times of 20-30 min.

  31. The problem with prolonged collection times is that the nature of the GCF sample collected is likely to change with the protein concentration of the initial GCF collected comparable to interstitial fluid. • Whereas prolonged sampling at the site resulted in protein concentrations approaching those of serum.

  32. Fluid Flow • Variation in fluid flow with time during the collection procedure greatly affect any quantitative observations on gingival fluid. • Depending upon collection procedure the amount of fluid production change in minutes following the contact of the paperstrip with marginal region. • Fluid flow increase during interacrevicular as compared to extracrevicular method.

  33. Volume determination • Evaporation is considered to be a significant problem in accurate volume determination of GCF samples. • This is particularly the case as the total volumes collected are usually less than 1µl and more often than not are less than 0.5 µl. • Concerns are also expressed regarding the accuracy of the calibration graph produced for the Periotron, particularly with respect to small volumes

  34. Both these factors will result in small errors of volume determination, because the total sample of GCF collected is small the percentage of error is considered to be of more major significance.

  35. Recovery from strips • Significant differences in the percentage recovery of proteins from filter papers is seen, which were dependent on both the type of paper and the concentration of the original protein sample. • Indeed, this may be a reason for conflicting results described between different research groups, possibly because of entrapment within, or binding of GCF proteins to the filter papers.

  36. PERIOTRON

  37. Volume of GCF • As Volume of GCF is low in healthy sites (0.5 ml in 30 sec ) ,

  38. Composition 1. Cellular elements - • Bacteria • Desquamated epithelial cells • Leukocytes – PMN’s • Lymphocytes • Monocytes / Macrophages. 2. Electrolytes • Potassium • Sodium • calcium

  39. 3. Organic compounds - • Carbohydrates Glucose hexosamine Hexuronic acid Glucose conc. is 3-4 times greater than serum • Proteins protein content is less than serum • Lipids • Metabolic and bacterial product Lactic acid, urea,endotoxins,h2s

  40. Enzyme and Enzyme inhibitors • 1. Acid Phosphatase • 2. Alkaline phosphatase • 3. Pyrophosphatase • 4. β-glycoronidase • 5. Lysozyme • 6. Hyaluronidase • 7. Proteolytic enzymes Neutrophil elastase Cathepsin G Plasminogen activitor Collagenase Cathepsin D

  41. DRUGS IN GCF • TETRACYCLINE BADER AND GOLDHABER (1966) CIANCIO (1976) • METRONIDAZOLE

  42. CLINICAL SIGNIFICANCE CIRCADIAN PERIODICITY SEX HORMONES MECHANICAL STIMULATION SMOKING PERIODONTAL THERAPY

  43. CLINICAL SIGNIFICANCE GENERAL HEALTH AND GINGIVAL FLUID • Circadian periodicity • Acc to intracrevicular technique flow is more in evening as compared to morning • But with orifice technique no difference in flow was found

  44. GCF FLOW AND SEX HARMONES • Clinical investigations have shown an exacerbation of gingivitis during pregnancy, during menstural cycle and at puberty. • Increased in tooth mobility and pocket depth have also been reported during pregnancy. • Estrogen and progesterone cause increase in GCF flow

More Related