These are basically of two types:
• Toxin neutralization
• Virus neutralization
In toxin neutralization homologous anti-bodies prevent the biological effect of toxin as observed in vivo in experimental animals (e.g. detection of toxin of Clostridia and Corynebacterium diphthenae) or by in vitro method (e.g. Nagler’s method).
In virus neutralization test various methods are available by which identity of virus can be established as well as antibody against a virus can be estimated.
Anti-nuclear antibodies (ANA) Systemic Lupus
Anti-dsDNA, anti-Smith Specific for Systemic Lupus
Anti-histone Drug-induced Lupus
Anti-IgG Rheumatoid arthritis
Anti-centromere Scleroderma (CREST)
Anti-Scl-70 Sclerderma (diffuse)
Anti-mitochondria 1oary biliary cirrhosis
Anti-gliadin Celiac disease
Anti-basement membrane Goodpasture’s syndrome
Anti-epithelial cell Pemphigus vulgaris
Anti-microsomal Hashimoto’s thryoiditis
CROSS INFECTION AND STERLIZATION IN DENTISTRY
Cross infection is defined as the transmission of infectious agents amongst patients and staff with in hospital environment.
Routes of Infection
Two routes are important : transdermal and respiratory.
In transdermal route microorganisms enter the tissues of the recipient by means of injection through intact skin or mucosa (usually due to an accident involving a sharp instrument) or via defects in the skin e.g. recent cuts and abrasions.
Microorganisms causing cross infection in dentistry
Transmitted through skin
Bacteria : Treponema pallidum, Staphylococcus aureus
Viruses :Hepatitis virus, HIV ,Herpes simplex virus, Mumps, Measles , Epstein-Barr virus
Fungi: Dermatomycoses, Candidiasis,
Transmitted through aerosols
Bordetella pertussis, Myco.tuberculosis, Streptococcus pyogenes, Influenza virus
DISINFECTION AND STERILIZATION
• Sterilization is the best destruction or com removal_of all forms of micro organisms.
• Disinfection is the destruction of many microorganisms but usually the b spores.
• Antisepsis is the destruction or inhibition of microorganisms in living tissues thereby limiting or preventing the harmful effect of infection.
• Astatic Agent would only inhibit the growth of microorganisms (bacteriostatic, fungistatic, sporostatic).
• Acidal agent would kill the microorganism (bactericidal. virucidal, fungicidal)
• Sterilants are the chemicals which under controlled conditions can kill sporinQ bacteria.
Complement Fixation Test (CFT)
This test is based upon two properties of the complement viz:
a. Complent combines with all antigen-antibody complexes whether or not it is required for that reaction
b. Complement is needed in immunolytic reaction.
It contains an antigen and a serum suspected to be having antibody to that antigen. The serum is heat treated prior to the test to destroy its complement. Complement Is added in measured quantity to this system. This complement is the form of guinea pig serum which is considered a rich source of complement. The test system is incubated.
To test system, after incubation, is added the indicator system which consists of sheep
RBCs and antibody to sheep RBCs (haemolysin) and another incubation is allowed.
If there is specific antibody in the test system, it will bind to antigen and to this complex the complement will also get fixed. Hence, no complement will be available to combine with indicator system which though contains RBCs and their specific antibody, cannot undergo haemolysis unless complement gets attached. Absence of haemolysis shall indicated positive test or presence of specific antibody in the serum which has been added in the test system. Erythrocytes lysis is obtained in negative test.
Method of Sterilization for common items
Autoclaving : Animal cages, Sugar tubes, Lab. Coats, Cotton , Filters, Instruments Culture media, Rubber, Gloves , Stopper, Tubing, Slides, Syringe and Wax needles , Test tubes, Enamel metal trays ,Wire baskets, Wood, Tongue depressor, Applicator, Endodontic instruments, Orthodontic pliers , Orthodontic kits, Saliva ejector, Handpieces Cavitron heads, Steel burs, Steel tumbler, Hand instruments
Hot air oven
Beakers, Flasks, Petri dish, Slides, Syringes, Test tubes, Glycerine, Needles ,Oil, Paper Saliva ejector, Matrix Band
Fabric, Bedding, Blanket, Clothing, Matteresses, Pillows, Disposable instruments , Instruments, Blades, Knives, Scalpels, Scissors ,Talcum powder, Books, Cups, plates , Plastics., Flask, Petridish, Tubes, Tubing, Rubber , catheters, Drains, Gloves ,Special items - Bronchoscope, Cystoscope, Heart lung machine
Orthodontic kits, Orthodontic pliers , Steel burrs, 3 in 1 syringe tips ,Cystoscope ,Endoscope
Antibiotics, Serum, Vaccines