www.indiandentalacademy.com
INDIAN DENTAL ACADEMY Leader in continuing dental education www.indiandentalacademy.com
www.indiandentalacademy.com
CONTENTS
Introduction Immunity Antigen Antibody Complement system Antigen – Antibody Reactions Hypersensitivity Autoimmunity Immunodeficiency Micro-organisms of relevance in dentistry Nosocomial Infection Cross infection Infection control Hospital waste disposal Conclusion List of references www.indiandentalacademy.com
INTRODUCTION
www.indiandentalacademy.com
Immunity: Latin word ‘Immunis’- exempt Resistance exhibited by the host towards any injury caused by micro-organisms & their products. HISTORY : 15th century – Chinese & Turks – Variolation 1798 - Edward Jenner – cowpox pustules in smallpox patients 1881 - Louis Pasteur coined ‘vaccine’ 1883 - Metchnikoff - phagocytes - ingest microorganisms
www.indiandentalacademy.com
1885 – Pasteur administered 1st vaccine 1901 - Emil vonBehring – serum from immunised animals transfer immunity 1930 – Elvin Kabat – gammaglobulins – immunity 1950 – Lymphocytes – cellular & humoral immunity
www.indiandentalacademy.com
Classification
www.indiandentalacademy.com
INNATE IMMUNITY: NON-SPECIFIC DEFENCE: 1. Mechanical barriers 2. Physicochemical barriers 3. Antibacterial substances 4. Elimination of infections agents through urine & bronchial secretions SPECIFIC DEFENCE: 1. Specificity for a particular antigen 2. Memory
www.indiandentalacademy.com
ACQUIRED IMMUNITY: Active immunity: resistance developed as a result of antigenic stimulus Natural Active immunity : Microbes eg : measles , chicken pox Artificial Active immunity : Vaccines eg : BCG Natural Passive immunity : Mother to child eg : IgA in Colostrum Artificial Passive immunity : Antibodies eg : Anti tetanus serum www.indiandentalacademy.com
IMMUNE SYSTEM :Lympho-reticular system Lymphoid cells Lymphocytes Plasma cells
Lymphoid organs Primary: Thymus, bone marrow Peripheral: Lymph node, spleen
• Antibody mediated / Humoral Immunity : Plasma cells • Cell mediated / Cellular Immunity : Lymphocytes • Specific Immunity
: Lymphocytes , Plasma cells
• Non Specific immunity : Phagocytic cells www.indiandentalacademy.com
SURFACE MARKERS: CD number CD 1 CD 2 CD 3 CD 4 CD 8 CD 19
Cell type association Thymocytes , langerhans cells T-cells T-cell antigen receptor complex Helper T-cells Suppressor or Cytotoxic T -cells B -cells
NULL CELLS: surface markers absent eg – NK cells , Antibody dependent cellular cytotoxic lymphocytes www.indiandentalacademy.com
ANTIGEN: Any substance which when introduced into the body, stimulates the production of an antibody with which it reacts specifically and in an observable manner. eg: cells, proteins, polysaccharides Attributes of Antigenicity: 1. Immunogenicity 2. Immunological reactivity Types: 1. Complete antigen 2. Hapten www.indiandentalacademy.com
ANTIBODY : Proteins that appear in circulation after infection or immunization and have the ability to react specifically with the antigen Also called gamma globulins.
STRUCTURE : Porter and Edelman
www.indiandentalacademy.com
PROPERTIES :
www.indiandentalacademy.com
FUNCTIONS : Ig G – protects body fluids Ig M – protects blood stream Ig A – protects body surfaces Ig D – recognizes antigens on the surface of B lmphocytes Ig E – mediates reagenic hypersensitivity ANTIGEN – ANTIBODY REACTION : Antigen and antibody combine with each other in a specific and observable manner • In vitro – Serological reactions • In vivo – Hypersensitivity reactions
www.indiandentalacademy.com
www.indiandentalacademy.com
CLASSIFICATION : Morphologically, 1. Precipitation reaction : soluble antigen + antibody 2. Agglutination reaction : insoluble antigen + antibody Functionally, 1. Neutralization 2. Complement fixation 3. Opsonization 4. Immunofluoresence 5. Enzyme immunoassay www.indiandentalacademy.com
COMPLEMENT SYSTEM : Complement : Factors which occur in the normal serum & are activated characteristically by antigen – antibody interaction and subsequently mediate a number of biologically significant reactions which form the complement system Ehrlich – complement Ig M and Ig G – fix the complement COMPLEMENT ACTIVATION : • Classical Pathway • Alternate or Properdin Pathway
www.indiandentalacademy.com
www.indiandentalacademy.com
www.indiandentalacademy.com
IMMUNE RESPONSE :
www.indiandentalacademy.com
HYPERSENSITIVITY : Abnormal state of immune reactivity that has deleterious effect on the host CLASSIFICATION: I. Depending on the time elapsed between exposure and appearance of symptoms : • Immediate • Delayed II. • • • •
Gel & Coombs Classification : Type I – Immediate Type II – Cytotoxic Type III – Immune complex Type IV – Delayed www.indiandentalacademy.com
www.indiandentalacademy.com
AUTOIMMUNITY : A condition in which a structural or functional damage is produced by the action of immunologically competent cells or antibodies against normal components of the body. eg : Rheumatoid arthritis, Sjogren’s syndrome, SLE MECHANISM : 1. Release of hidden or sequestered antigen into the circulation. 2. Antigenic alteration in cells or tissues due to physical, chemical or biological influences 3. Defects of T and B cells 4. Increase in helper T cells & decrease in cytotoxic T cells www.indiandentalacademy.com
IMMUNODEFICIENCY : Immunodeficiency diseases are the conditions where the defence mechanisms of the body are impaired , leading to repeated microbial infection of varying severity and sometimes enhanced susceptibility to malignancies CLASSIFICATION : I. II.
Primary Secondary
www.indiandentalacademy.com
PRIMARY IMMUNODEFICIENCY INCLUDES 1. DISORDERS OF SPECIFIC IMMUNITY A. B-cell defects B. T-cell defects C. Combined immunodeficiencies (T and B cells) 2. DISORDERS OF COMPLEMENT A. Complement component deficiencies B. Complement inhibitor deficiencies 3. DISORDERS OF PHAGOCYTOSIS A. Chronic granulomatous disease B. Chediak Higashi syndrome C. Leucocyte G6PD deficiency D. Lazy leucocytewww.indiandentalacademy.com syndrome
SECONDARY IMMUNODEFICIENCES 1. Malnutrition – Protein Energy Malnutrition, Vitamin D deficiency 2. Systemic disorders – Hypogammaglobulinemia, renal insufficiency, extensive burns, uncontrolled diabetes 3. Drug induced – cytotoxic drugs, corticosteroids, antimicrobial drugs, captopril, silver salts, phenytoin 4. Surgery 5. Malignancy – B-cell malignancy, Non-Hodgkin’s lymphoma 6. Infectious diseases – HIV, EBV www.indiandentalacademy.com
MICRO-ORGANISMS OF RELEVANCE IN DENTISTRY 1. BACTERIA a. Gram positive – Streptococcus, Staphylococcus, Corynebacterium, Lactobacilli, Actinomyces, Clostridium b. Gram negative – Hemophilus, Salmonella, Actinobacillus, Bacteroides, Porphyromonas, Fusobacterium c. Spirochetes – Treponema d. Mycobacterium 2. VIRUSES a. DNA viruses – HPV, Herpes virus b. RNA viruses – Hepatitis B, HIV, Measles, Mumps 3. FUNGI – Candida, Cryptococcus neoformans www.indiandentalacademy.com
Infections caused by gram positive organisms 1. Streptococcus pyogenes (group A) – a. tonsillitis, b. pharyngitis, c. scarlet fever, d. sinusitis, e. wound infection leading to cellulitis and lymphangitis f. Rheumatic fever Streptococcus viridans – a. Plaque b. Caries www.indiandentalacademy.com c. Infective endocarditis
Infections caused by gram positive organisms – cont. 2. Staphylococci – a. Superficial infections (boil, carbuncle, pustule, abscess, conjunctivitis) b. Deep infections (osteomyelitis, endocarditis, septicemia) c. Toxic Shock Syndrome
2. Corynebacterium diphtheriae – a. Diphtheria
2. Lactobacilli – www.indiandentalacademy.com a. deep carious lesions
Infections caused by gram positive organisms – cont. 5. Actinomyces – a. Actinomycosis
6. Clostridium – a. Clostridium tetani (tetanus), b. Clostridium perfringens (Gas gangrene, food poisoning)
www.indiandentalacademy.com
Infections caused by gram negative organisms 1. E. coli and Salmonella – a. septicemia b. osteomyelitis
2. Hemophilus a. osteomyelitis, b. acute epiglossitis
3. Actinobacillus – a. LJP, b. rapidly destructive adult periodontitis www.indiandentalacademy.com
Infections caused by gram negative organisms – cont. 4. Capnocytophaga – a. periodontal pockets
4. Fusobacterium – a. ANUG, b. Vincent`s angina, c. Cancrum oris (Noma)
4. Bacteroides and Porphyromonas – a. Periodontitis
www.indiandentalacademy.com
Infections caused by mycobacterium and spirochetes 1. Mycobacterium – a. TB b. Leprosy
2. Treponema – a. Syphilis b. ANUG
www.indiandentalacademy.com
Infections caused by Herpes virus •
Herpes simplex a. HSV 1 – primary gingivostomatitis, Herpetic Whitlow, Conjunctivitis, Keratitis, Encephalitis. b. HSV 2 – genital lesions
•
Varicella Zoster a. Chicken pox b. Herpes zoster – reactivation of virus in the dorsal root or trigeminal ganglion c. Ramsay Hunt syndrome – herpes zoster with rash on tympanic membrane and external auditory canal with unilateral facial nerve palsy www.indiandentalacademy.com
Infections caused by Herpes virus – cont. •
Cytomegalovirus (CMV) a. Infection of salivary gland
•
Ebstein barr virus a. Infectious mononucleosis b. Burkitt’s lymphoma c. Nasopharyngeal carcinoma d. Hairy leucoplakia
•
Human herpes virus a. HHV8 - Kaposi’s sarcoma in AIDS www.indiandentalacademy.com
HEPATITIS B (SERUM HEPATITIS) •
DNA virus
•
Transmitted through parentral route, saliva
•
Incubation period = 1 – 6 months
•
Hepatitis B and dentistry •
Dentists are highly prone
•
HBV present in increased concentration in gingival sulcus as a result of continuous serum exudate
•
Also present in mixed saliva www.indiandentalacademy.com
Infections caused by RNA viruses •
Paramyxovirus a. Mumps – parotitis b. Measles – acute febrile illness + exanthematous rash
•
Coxsackie virus – Herpangina
•
Hepatitis A virus – infectious hepatitis
•
HIV – AIDS www.indiandentalacademy.com
AIDS (Acquired Immunodeficiency Syndrome) •
First reported in USA in 1981
•
Caused by HIV
•
Modes of transmission 1. Sexual contact 2. Sharing of needles and syringes among IV drug users 3. Mother to child (transplacental, perinatal, breast feeding) 4. Blood transfusion 5. Transplantation of infected organs www.indiandentalacademy.com
HIV and immune system – •
Primary targets are CD4 cells particularly Helper T-cells
•
Specific binding of virus to CD4 by envelope glycoprotein gp120
HIV infection is divided into – 1. Group I – acute infection 2. Group II – asymptomatic infection 3. Group III – persistent generalized lymphadenopathy 4. Group IV – ARC (AIDS related complex) www.indiandentalacademy.com
Oral manifestation of HIV infection •
Group I – lesions strongly associated with HIV •
•
Candidiasis, hairy leucoplakia, NUG, NUP, Kaposi’s sarcoma
Group II – lesions less commonly associated with HIV •
Mycobacterium avium intracellulare, necrotizing stomatitis, ulcerations, xerostomia, thrombocytopenic purpura, HSV, HPV, Herpes zoster
www.indiandentalacademy.com
Group III – lesions seen in HIV • • • • •
Bacterial – actinomycosis, K. pneumoniae Fungal – cryptococcus, histoplasma Viral – CMV Parasitic - pneumocystitis carnii Drug reactions – Lichenoid reactions, recurrent aphthous stomatitis
MANAGEMENT – 1. Surveillance 2. Antibiotics 3. Isolation www.indiandentalacademy.com
FUNGAL INFECTIONS Candidiasis : most common •
Causes mucosal, cutaneous and mucocutaneous lesions
•
Seen in – •
old age,
•
immunocompromised patients,
•
patients on heavy antibiotics,
•
oral contraceptives,
•
ill fitting dentures,
•
malignancy,
•
radiation,
•
heavy smoking.
www.indiandentalacademy.com
INFECTION : Invasion and multiplication of micro-organisms in body tissues causing local cellular injury due to competitive metabolism, toxins, intracellular replication or antigen-antibody reaction.
CROSS INFECTION : It is the spread of micro-organisms from one person to another and takes place by the following pathways – 1. Patient to dental personnel 2. Dental personnel to patient 3. Patient to patient www.indiandentalacademy.com
ROUTES OF CROSS CONTAMINATION : • Direct contact • Droplet infection • Indirect contact In dentistry cross infection occurs through : • • • • •
Needle sticks & instrument puncture Invisible breaks or cuts in the skin Mucous membrane of the mouth , nose , eyes Through open lesions Inhalation
www.indiandentalacademy.com
HOSPITAL ACQUIRED INFECTIONS (Nosocomial infections) : Infections developing in hospitalized patients, not present at the time of their admission.
Causes : •Exogenous – hospital ecosystem •Iatrogenic – invasive diagnostic or therapeutic procedures •Opportunistic micro-organisms www.indiandentalacademy.com
MICROBIOLOGY : • Staphylococcus aureus, S.epidermidis, Gp D Streptococci • Gram –ve bacilli - E.coli , Klebsiella , Pseudomonas • Viruses - HIV , CMV , HSV ,Hepatitis B • Fungi – Candida , Aspergillus
COMMON INFECTIONS : • Wound infections • UTI infections • Respiratory infections • Bacteremia & Septicemia www.indiandentalacademy.com
INFECTION CONTROL PROCEDURES Infection control procedures can be described under two headings : 1. Personal protection measures 2. Patient protection measures PERSONAL PROTECTION MEASURES : Prevention of cross infection from patient to dental personnels & involves : 1.
Personal hygiene
2.
Clinic clothing
3.
Barrier protection (gloves , eye shields ,face masks) www.indiandentalacademy.com
Personal hygiene : 1. 2. 3. 4.
Refrain from touching anything not required for the procedure Cover cuts and bruises on fingers Hair should be tied up properly Hands washed before & after treatment
Clinic clothing : 1. 2. 3.
Changed daily Aprons worn to protect the clothing Aprons washed thoroughly and bleached
www.indiandentalacademy.com
Gloves : ADA & CDC recommend use of gloves Types : 1. Clean , high quality ,protective latex gloves 2. Sterile gloves 3. Heavy duty utility gloves Materials used : 1. Latex 2. Vinyl
www.indiandentalacademy.com
Eye shields : Protect the eyes from • spatter and debris • conjunctivitis • Eye wear cleaned regularly • Eye wear with side protection preferred Face masks : Prevent inhalation of contaminated aerosols Filtration efficacy depends on : • Materials used (paper mask < glassfibre / polypropylene) • Duration (30 – 60 min ) www.indiandentalacademy.com
Rubber dam isolation : • Minimizes saliva & blood contaminated aerosol production • Provides clear visual field • Minimizes instrument contact with the mucosa (minimizing tissue injury & subsequent bleeding) PATIENT PROTECTION MEASURES • Disinfection • Sterilization
www.indiandentalacademy.com
•
Asepsis is freedom from pathogens
•
Antisepsis is the procedure which inhibits or destroys microbes on living tissues
•
Sterilization is the process by which an article, surface or medium is freed of all microorganisms either in the vegetative or spore state.
•
Disinfection is the process by which pathogenic organisms are removed from the surface or an object. This does not include bacterial endospores.
www.indiandentalacademy.com
â&#x20AC;˘
Disinfectants used in dentistry :
1.
Alcohols
2.
Iodine products
3.
Synthetic phenols
4.
Aldehydes
5.
Chlorine products
www.indiandentalacademy.com
ALCOHOLS: •
Traditionally used in dentistry as a disinfectant.
•
Isopropyl alcohol - most commonly used alcohol - 60-70% in water.
•
Mechanism - Denatures bacterial protein. - bactericidal , virucidal ,not sporicidal
Advantages : 1. Economical Disadvantages: 1. Ineffective in the presence of saliva or blood. 2. Rapid evaporation limits activity. www.indiandentalacademy.com
3. Damage rubber , plastic items
ALDEHYDES: •
Formaldehyde:
•
Mechanism : Acts on amino group of bacterial protein - bactericidal ,virucidal ,sporicidal
•
10% formalin + sodium tetra borate is used to disinfect cleaned metal instruments.
•
Formaldehyde gas - heat sensitive instruments - fumigation of wards , laboratories
•
Disadvantages : Formaldehyde gas is irritant and toxic when inhaled. www.indiandentalacademy.com
• Gluteraldehyde : 2 % gluteraldehyde for less than 20 min – disinfectant • Mechanism : - acts on bacterial proteins - bactericidal , virucidal ,sporicidal ( if used for 6 – 10 hours ) • Advantages : - used with rubber and plastic items - less toxic , non corrosive • Disadvantages : - allergenic - severe tissue irritation - may discolour some metals www.indiandentalacademy.com
IODOPHORES: •
Iodophores are compounds of iodine with nonionic wetting or surface active agents. eg: Povidone iodine [Betadine]
•
Mechanism : - act on bacterial protein - bactericidal , virucidal
•
Advantages : economical safe
•
Disadvantages : - may discolour surfaces - unstable at high temperatures www.indiandentalacademy.com
CHLORINE : • Mechanism : cell wall damage, enzyme system blockage, protoplasmic poisoning. • Effective against a wide spectrum of bacteria and viruses. • Advantages : - rapid action - economical • Disadvantages: unstable corrodes metal and softens plastic irritant to eye and skin. www.indiandentalacademy.com
PHENOL : •
Mechanism : Causes cell membrane damage and cell lysis.
•
Synthetic derivatives like lysols and cresols are active against wide range of organisms.
•
Effectiveness of phenolic compounds depends on contact with bacterial cell.
•
Advantages : economical less toxic used on metals , rubber , plastics
•
Disadvantages : not sporicidal irritant to eyes , skin www.indiandentalacademy.com
SURFACE ACTIVE AGENTS: • They reduce surface tension. • Cationic surface acting agents Quarternary ammonium compounds • Mechanism : - act on phosphate group of cell membrane - bactericidal only • Anionic surface acting agents – Soaps • Mechanism : act on gram positive and gram negative bacteria www.indiandentalacademy.com
Methods of
www.indiandentalacademy.com
STERILIZATION can be divided into : 1.
Presterilization cleaning
2.
Packaging
3.
Sterilization process
4.
Aseptic storage
PRESTERILIZATION CLEANING : 1.
Removal of contaminated instruments
2.
Heavy duty utility gloves used
3.
Sharps handled carefully
4.
Scrubbing manual ultrasonic www.indiandentalacademy.com
PACKAGING : â&#x20AC;˘ Protects cleaned instruments from recontamination â&#x20AC;˘
Instruments packaged using : 1. See - through sterilization bags 2. Self sealing paper / plastic pouches 3. Single layered cloth wrap
www.indiandentalacademy.com
STERILISATION PROCESS : •
Physical agents: 1. Dry heat 2. Moist heat 3. Radiation 4. Ultrasonic and sonic vibration
•
Chemical agents: •
Gases 1. Ethylene oxide gas
•
Aldehydes 1. Gluteraldehyde www.indiandentalacademy.com 2. Formaldehyde
In dentistry commonly used methods for sterilization are : •
Dry heat 1. Hot air oven 2. Rapid heat sterilizer 3. Glass bead sterilizer
•
Moist heat 1. Autoclave
•
Chemical 1. Unsaturated chemical vapor sterilization 2. Gluteraldehyde solution www.indiandentalacademy.com
HOT AIR OVEN: •
Dry heat denatures protein of microorganisms rendering them nonviable.
•
Temperature of 160oC for 1-2 hours.
•
Sterilization time begins only after the proper temperature of 160°C is reached and then this temperature must be maintained.
•
Advantages: 1] no corrosion 2] Cost effective 3] Items are dry after cycle
•
Disadvantages: 1] longer sterilization time 2] Cannot sterilize liquids 3] May damage plastic and rubber items www.indiandentalacademy.com
RAPID HEAT STERILIZER: •
Uses controlled internal air flow system at 375°F.
•
Sterilization claims of 6 minutes are made with unwrapped instruments and 12 minutes for wrapped instruments.
Advantages: 1] no corrosion 2] Short cycle 3] Items are dry after cycle
www.indiandentalacademy.com
Disadvantages: 1] cannot sterilize liquids 2] May damage plastic and rubber items
GLASS BEAD STERILIZATION: â&#x20AC;˘Used for small instruments like burs ,trimmers etc. â&#x20AC;˘Temperature - 450oC for 5-30 seconds
www.indiandentalacademy.com
AUTOCLAVE: •
Moist heat denatures and coagulates protein of microorganisms.
•
Sterilization is due to latent heat of vaporization present in moist heat.
•
When steam condenses on contact with cooler surfaces, it becomes water and gives latent heat to that surface.
•
This principle is used in autoclave.
www.indiandentalacademy.com
•
Temperature - 121°C for 20 minutes at 15 pounds pressure.
•
For practical considerations high pressure vacuum models are operated at a temperature of 136°C for 5 minutes at 30 pounds pressure.
•
Advantages: 1] good penetration 2] Time efficient 3] Sterilize water based liquids
•
Disadvantages: May damage plastic or rubber items www.indiandentalacademy.com
ETHYLENE OXIDE STERILIZATION: •High penetrating ability. •It acts by alkylating the amino, carboxyl, sulphydril groups in protein molecules and reacts with RNA and DNA. •Used to sterilize heat sensitive instruments. •Disadvantages: 1.Slow procedure - 4 hours at 54oC and 12 hours at room temperature. 2.Costly
www.indiandentalacademy.com
LIQUID STERILIZATION: •
2-3.2% Gluteraldehyde solution can kill microorganisms and spores in 6-10 hours at room temperature.
•
Used for plastic or other items which cannot survive heat sterilization.
•
Items precleaned and dried ; submerged in solution for required time and thoroughly rinsed.
•
Lower concentration or lesser time leads to disinfection
www.indiandentalacademy.com
Sterilization : ADA recommendations •
Rubber items and saliva ejectors: Best method - discard after each use. Ethylene oxide sterilization , dry or moist heat sterilization -ineffective
•
Hand pieces: Steam, dry heat, chemical vapour and ethylene oxide sterilization are preferred
•
Burs and Stones: Dry heat , chemical vapour and ethylene oxide gas sterilization preferred. Polishing stones - chemical vapour and ethylene oxide gas www.indiandentalacademy.com
•
Impression trays: Aluminum trays – autoclave , chemical vapor Chrome plated trays - all methods of sterilization can be employed. Plastic or acrylic trays - ethylene oxide or gluteraldehyde sterilization.
•
Stainless steel hand instruments: Autoclave, dry heat, chemical vapour and ethylene oxide sterilization.
•
Gloves and gauze - autoclaved. www.indiandentalacademy.com
•
Tongue blade, lip and cheek retractors - steam or dry heat
•
Matrix band, spatula, light cure tip - steam or gluteraldehyde sterilization.
•
Glass slab and dappendish - steam, dry heat or chemiclave.
•
Three way syringe – gluteraldehyde sterilization or chemiclave www.indiandentalacademy.com
RECOMMENDATIONS FOR DISINFECTING IMPRESSION MATERIALS DISINFECTANTS IMPRESSION MATERIALS
GLUTARALDEHYDE
IODOPHORS
SODIUM HYPOCHLORITE
ALGINATE
No
Yes
Yes
POLYSULFIDE
Yes
Yes
Yes
SILICONES
Yes
Yes
Yes
POLYETHERS
No
Yes
Yes
REVERSIBLE HYDROCOLLOID
No
Yes
Yes
No Yes www.indiandentalacademy.com
Yes
COMPOUND
RECOMMENDATIONS FOR DISINFECTING PROSTHETIC DEVICES AND APPLIANCES DISINFECTANTS PROSTHETIC DEVICE GLUTARALDEHYDE
IODOPHORS
SODIUM HYPOCHLORITE
COMPLETE DENTURES
No
Yes
Yes
REMOVABLE PARTIAL DENTURES
No
Yes
Yes/ No
FIXED PROSTHESIS
Yes
No
Yes/ No
STONE CASTS
No
Yes
Yes
WAX RIMS
No
Yes
No
www.indiandentalacademy.com
WASTE DISPOSAL : Biomedical waste: Any waste which is generated during the diagnosis , treatment or immunization of human beings or animals or in research activities pertaining thereto or in the production or testing of biologicals CLASSIFICATION : 1. Infectious waste 2. Pathologic waste 3. Sharps 4. Pharmaceutical waste 5. Chemical waste 6. Radioactive waste www.indiandentalacademy.com
METHODS OF WASTE DISPOSAL 1. Incineration :high temperature dry oxidation waste that cannot be reused, recycled 2. Chemical disinfection :liquid wastes like blood 3. Microwave irradiation 4. Land disposal :open dumps sanitary landfill 5. Inertization : waste + cement + lime
www.indiandentalacademy.com
COLOUR CODING AND TYPE OF CONTAINER FOR DISPOSAL OF BIOMEDICAL WASTES COLOUR CODING YELLOW
TYPE OF CONTAINER Plastic bag
WASTE CATEGORY
TREATMENT OPTIONS
Human anatomical wastes, animal waste, microbiology and bio technology wastes and solid wastes Microbiology and bio technology wastes and solid wastes
Incineration/deep burial
RED
Plastic bag/disinfected container
BLUE/WHITE TRANSLUCENT
Plastic bag/puncture proof container
Waste sharps and solid wastes
Autoclaving/microwa ve/chemical treatment/shredding
Plastic bag
Discarded medicines, incineration ash and chemicals used in production of biologicals
Disposal in secured landfill
BLACK
www.indiandentalacademy.com
Autoclaving/microwa ve/chemical treatment
CONCLUSION
www.indiandentalacademy.com
List of references : 1. 2. 3. 4. 5. 6. 7. 8. 9.
Medical immunology – Gabriel Virella , 5th ed Immunology – Richard Goldsby , 5th ed Textbook of Microbiology – Ananthnarayan , 6th ed Disinfection , Sterilization & Prevention - Block.S.S, 5th ed Essential Microbiology for dentistry - Samaranayke ,2nd ed Park’s Textbook of Preventive & Social Medicine - K. Park , 17th ed Dentistry International 2005, 24 – 27 DCNA 1992 April JADA 1989 www.indiandentalacademy.com
www.indiandentalacademy.com Leader in continuing dental education
www.indiandentalacademy.com