impact of sterilization and disinfectionon prosthodontic practice with bird's view on covid

1. Presented by:-
Dr. Saumya
PG 1ST YEAR PROSTHODONTICS

2. CONTENTS:-
 INTRODUCTION
 DEFINITIONS
 CLASSIFICATIONS OF BACTERIA AND VIRUS
 METHODS OF STERILISATION
1. PHYSICAL METHODS
2. CHEMICAL METHODS
 DISINFECTANTS
 SPAULDING' S CLASSIFICATION
 STERILIZATION IN PROSTHODONTIC PRACTICE
 DISINFECTION IN PROSTHODONTIC PRACTICE
 COVID AND ITS IMAPCT ON PROSHODONTIC PRACTICE
 REFERENCES

3. INTRODUCTION
1. UBIQUITOUS DISTRIBUTION OF MICROORGANISM
2. KNOWN TO CAUSE CONTAMINATION, INFECTIONAND DECAY
3. LOUIS PASTEUR INTRODUCED THE CONCEPT OF STERILIZATION
4. DR.JOSEPH LISTER INTRODUCED CARBOLIC ACID , ALSO KNOWN AS
PHENOL FOR THE STERILIZATION OF THE INSTRUMENTS AND WOUNDS.
5. KNOWN AS FATHEROF MODERN ANTISEPTIC SURGERY.
6. DISEASE TRANSMISSION MEDIATED VIA DENTAL CLINC AND LABS ARE
DOCUMENTED AND HENCE THE NEED OF STERILIZATION IS MUST.

4. MECHANISM OF TRANSFER OF
INFECTIONS :-
a) CROSS-CONTAMINATION
EX;-COVID-19
b) DIRECT CONTACT TRANSMISSION
EX;- CONJUCTIVITIS, HERPES SIMPLEX, HEPATITIS AAND B
c) INDIRECT CONTACT TRANSMISSION
EX:- COMMON COLD,LARYNGITIS ETC.
d)DROPLET INFECTION
EX:-MUMPS,PERTUSIS, RUBELLA
e)AIRBORNE INFECTION
EX:- TUBERCULOSIS

5. DEFINITIONS
1. STERILISATION:- THE PROCESS BY WHICH AN ARTICLE SURFACE OR MEDIUM
IS FREED OF ALL LIVING ORGANISMS EITHER IN VEGETATIVE OR SPORE FORM.
2.STERILANT:- THE AGENT CAPABLE OF STERILISING OBJECTS
3.DISINFECTION:- IT MEANS DESTRUCTION OR REMOVAL OF ALL PATHOGENIC
ORGANISMS , CAPABLE OF GIVING RISE TO INFECTIONS,BUT NOT NECESSARLIY
SPORES
4.DISINFECTANTS:- PRODUCTS USED TO KILL MICROBES ON INANIMATE OBJECTS
AND SURFACES.
5. ANTISEPSIS:- IT INDICATES PREVENTION OF INFECTION USUALLY
BYINHIBITING THE GROWTH OF BACTERIA IN WOUNDS/ TISSUES.

6. 6) ANTISEPTICS:- PRODUCTS WHICH CAN BE SAFELY APPLIED TO LIVING
TISSUES.
7) BACTERIAE:- MEMBEROF A LARGE GROUP OF UNICELLULAR
MICROORGANISMS WHICH HAVE CELL WALLS BUT LACK ORGANELLES AND AN
ORGANISED NUCLEUS , INCLUDING SOME THAT CAN CAUSE DISEASE.
8)VIRUS :-LARGE GROUP OF SUBMICROSCOPIC INFECTIOUS AGENT THAT
REPLICATES INSIDE THE LIVING CELLS OF AN ORGANISM AND TYPICALLY
CONSISTS OF NUCLEIC ACID MOLECULE IN A PROTEIN COAT .

7. CLASSIFICATION OF BACTERIAAND VIRUS
1. BASED ON ANATOMICAL FEATURES
a) CAPSULATED
b) FLAGELLATED
c) SPORE FORMING
2. BASED ON STAINING REACTION
a) GRAM ‘S STAIN
1) GRAM POSITIVE
2) GRAM NEGATIVE
b) ACID FAST STAIN
1)Acid – fast bacilli
2)non- acid-fast bacilli
3. BASED ON TEMPERATURE
a)PSYCHROPHILES
b) MESOPHILES
c) THERMOPHILES
d) EXTREMELY THERMOPHILES

8. CLASSIFICATION OF VIRUS
1) BASED ON THE NUCLEIC ACID
a) DNA VIRUS
b) RNA VIRUS
c)DOUBLE STRANDED
d) SINGLE STRANDED
2) BASED ON THE SHAPE OF CAPSID
a) ICOSAHEDRAL
b) HELICAL
3) BASED ON THE PRESENCE OR ABSENCE OF ENVELOPE
a) NAKED
b) ENVELOPED

9. METHODS OF STERILISATION
• PHYSICAL METHODS
• SUNLIGHT
• HEAT (a)DRY HEAT
( b)MOIST HEAT
• OZONE
• FILTERATION
• RADIATION
CHEMICAL METHODS
• ALCOHOLS
• ALDEHYDES
• PHENOLS
• HALOGENS
• OXIDISING AGENTS
• GASES

10. SUNLIGHT
- MOST EFFECTIVE METHOD OF STERILISATION
- PRESENCE OF UV RAYS AND HEAT RAYS
MECHANISM OF ACTION:-
• HAS SHORT WAVE LENGTH
• GERMICIDAL IN ACTION
• DESTROYS THE NUCLEIC ACIDS AND HENCE DISRUPTS THE
REPLICATION OF MICROORGANISMS
2. HEAT - COMMONLY USED AND RELIABLE
TWO TYPES OF HEAT ARE USED – DRY AND MOIST
MECHANISM OF ACTION:-
DRY HEAT
1. BY DENATURATING THE BACTERIAL PROTEINS
1. INITIATING OXIDATIVE DAMAGE

11. MOIST HEAT
1. EMPLOYES DENATURATION AND COAGULATION OF PROTEINS
2. DRY HEAT STERILIZATION METHODS:-
1. RED HEAT
2. FLAMING
3. INCINERATION
4. HOT AIR OVEN
1. RED HEAT :-
• INOCULATING WIRES, TIPS OF THE FORCEPS HEATED TILL THEY TURN
RED HOT
• BUNSEN BURNER IS USED
2. FLAMING:-
• GLASS SLIDES ,SCALPELS , STERILIZES
PASSED THROUGH THE BUNSEN BURNER

12. INCINERATION:-
1. CONVERTING THE INFECTED MATERIAL INTO ASHES BY
BURNING
2. INCINERATOR IS USED
3. SOILED DRESSINGS, ANIMAL WASTES ,BEDDING AND
PATHOLOGICAL MATERIALS

13. HOT AIR OVEN :-
1. DRY HEAT IS EMPLOYED
2. ELECTRICALLYHEATED
3. FAN IS INSTALLED --UNIFORM DISTRIBUTION OF HOT AIR
4. THERMOSTAT –TO MAINTAIN THE TEMPERATURE
5. TEMPERATURE - 160 DEGREE FOR 2 HOURS
USES
1.GLASSWARES
2. SURGICAL INSTRUMENTS

14. STERILISATION CONTROL
• CLOSTRIDIUM tetani SPORES
• DESTROYED SPORES – SIGN OF EFFECTIVE STERILIZATION
• THERMOCOUPLES
• BROWNE’S TUBE WITH GREEN SPOT
• AFTER PROPER STERILISATION , GREEN COLOR IS PRODUCED

15. GLASS BEAD STERILIZER
• STERILIZES SMALL INSTRUMENTSSUCH AS ENDODONTIC FILES , FORCEPS
, SCISSORS , BURS
• WORKS AT 425 DEGREE FARENHEIT FOR 10 SEC
• UTILISES THE PRINCIPLE OF DRY HEAT
• GLASS BEADS SHOULD BE LESS THAN 1 MM IN SIZE
• LARGER GLASS BEADS CAN’T TRANSFER THE HEAT DUE TOLARGE
SPACES IN BETWEEN THEM.

16. MOIST HEAT STERILISATION
1. USES HOT WATER VAPOUR -- STERILIZING AGENT
2. ACTION – DENATURATION OF BACTERIAL PROTEINS
3. METHOD OF STERILIZATION ARE USED AT
DIFFERENT TEMPERATURES
• AT A TEMPERATURE BELOW 100 DEGREE CELSIUS
• AT A TEMPERATURE 100 DEGREE CELSIUS
• AT A TEMPERATURE ABOVE 100 DEGREE CELSIUS

17. MOIST HEAT
BELOW 100
DEGREE
AT 100
DEGREE
ABOVE 100
DEGREE
PASTEURISATIO
N
INSPISSATION
VACCINE BATH
BOILING
TYNDALLIZATION
STEAM
STERILIZER
AUTOCLAV
E
( STEAM
UNDER
PRESSURE)

18. AT A TEMPERATURES BELOW 100 DEGREE
a) PASTEURISATION :-
• LOUIS PASTEUR POSTULATED IT
• HOLDER METHOD- 63 DEGREE FOR 30 MINUTES
• FLASH METHOD- 72 DEGREE FOR 20 SECONDS AND FOLLOWED BY
COOLINGTO 13 DEGREE .
b) INSPISSATION :-
• INSPISSATOR IS USED
• LJ MEDIA , EGG MEDIAARE STERILED AT 80-85 DEGREE FOR 30 MIN
CONSECUTIVELY FOR 3 DAYS .
c) VACCINE BATH:-
• WATER BATHS -TEMPERATURE SET VERY LOW
VACCINES ARE STERILIZED AT 60 DEGREE FOR 1 HOUR

19. AT A TEMPERATURE OF100 DEGREE CELSIUS
BOILING-
• IT IS PHASE CONVERSION OF LIQUID TO VAPOUR
• BOILING FOR 130-30 MIN KILL THE VEGETATIVE FORMS OF BACTERIA
EX:- GLASS SYRINGES , RUBBER STOPPERS.
TYNDALLISATION:-
STEAM AT 100 DEGREE FOR 20 MIN FOR 3 SUCCESSIVE DAYS
1) FIRST EXPOSURE KILLS VEGETATIVE FORMS
2)GRMINATE INTO VEGETATIVE FORMS
3) FURTHER STEAMING KILLS VEGETATIVE FORMS
• Used for sterilization of egg, serum and sugar

20. STEAM STERILIZER / KOCH ‘S STEAM STERILIZER
• CAN BE USED FOR THE MEDIAS WHICH CANNOT STAND HIGH
TEMPERATURE OF AUTOCLAVE.
• PERFORATED TRAYS ARE PRESENT , WHICH STEAM CAN PASS.
• WORKS AT 100 DEGREE FOR 90 MIN AT ATMOSPHERIC PRESSURE
• MECHANISM OF ACTION:-
• IRREVERSIBLE COAGULATION
• DENTAURATION OF ENZYMES
• STRUCTURAL PROTEINS

21. AUTOCLAVE
• 121 DEGREE CELSIUS -15 lb PRESSURE &15 MIIN.
• FLASH STERILISATION -133 DEGREE AT 30lb for 3 min
COMPONENTS:-
1. VESSEL - MAIN BODY OF THE AUTOCLAVE
2. CONTROL SYSTEM - INBUILT PROGRAMME TO GUIDE THE
STERILIZATION CYCLE
3. THERMOSTATIC TRAP – TO REGULATE THE ESCAPEMENT OF STEAMOF
AIR AND WATER FROM THE CHAMBER
4. SAFETY VALVE – TO REGULATE OPTIMISATION OF PRESSURE
5. WASTE WATER COOLING MECHANISM- TO COOL DOWN THE WATER
BEFORE LETTING IT IN DRAIN
6. STEAM GENERATOR- SOURCE OF THE STEAM GENERATING
.

23. STERILIZATION CYCLES
STERILIZATION
CYCLES:-
BASIC CYCLES DESCRIPTION LOAD TYPE
GRAVITY
STEAM DISPLACES AIR IN
THE CHAMBER BY
GRAVITY
GLASSWARES,UNWRAP
PED GOODS ,
WASTE,UTENSILS ,
PRE- VACUUMAND /OR
POST- VACUUM
AIR IS MECHANICALLY
REMOVEDFROM THE
CHAMBER THROUGH
SERIES OF VACUUM AND
PRESSURE PULSS
• STEAM PENETRATES
POROUS AREAS OF THE
LOAD
WRAPPED GOODS ,
ANIMALCAHE BEDDING
, CAGES,WRAPPED
SURGICAL
INSTRUMENTS
LIQUIDS A GRAVITY CYCLE WITH A
SLOWER EXHAUST TO
MINIMIZE BOIL OVER
MEDIA , LB BROTH ,
WATER
IMMEDIATE US / FLASH HIGH TEMPERATURE
CYCLE FOR SHORTER
PERIOD OF TIME
UN WRAPPED
INNSTRUMENTS

24. STERILISATION CONTROL
1. THERMOCOUPLE – TO RECORD THE TEMPERATURE THROUGH
POTENTIOMETER
2. BACTERIAL SPORES- BACILLUS stearothermophillus are used
spores are kiiled at 121 degree in 12 min
Chemical indicators
• BROWNE’S TUBE CONTAINSRED SOLUTION THAT TURNS GREEN ON
EXPOSING TO 121 DEGREE FOR 15 MIN
• STRIPS ARE AVAILABLE
• TO ENSURE UNIFORM DISTRIBUTION OF STEAM OVER THE LOAD PLACED
IN THE AUTOCLAVE.

25. OZONE ( LOW TEMPERATURE STERILIZATION)
• OZONE IS HIGHLY REACTIVE GAS COMPOSED OF 3 OXYGEN ATOMS
MECHANISM OFACTION:-
• OXIDIZES THE ORGANIC MATERIAL IN BACTERIAL MEMRANES
• RUNS AT LOW TEMP . OF 25-35 DEGREE CELSIUS
• STERILITY IS ACHIEVED IN 4 HOURS.

26. FILTERATION:-
• USED FOR THE SUBSTANCES WHICH GET DESTROYED BY HEAT PROCESS
• EX. SERA , SUGARS, ANTIBIOTIC SOLUTIONS
• USES:- VIRUS ISOLATION
• PURIFICATION POF WATER
TYPES OF FILTERS:-
• EARTHENWARES CANDLES – AVAILABLE IN HOLLOW CYLINDERS
• USED FOR PURIFICATION OF WATER
• TWO TYPES :-DIATOMACEOUS EARTH FILTERS
UNGLAZED FILTERS

27. ASBESTOS DISC FILTERS-
• MADE UP OF ASBESTOS
• SINGLE USE
MEMBRANE FILTERS:-
• MADE UP OF CELLULOSE ESTERS
• AVAILABLE IN PORE SIZES OF 0.015 TO 12MICROMETER
• 0.22 MICROMETER IS COMMONLY USED AS IT IS SMALLER THAN THE SIZE
OF THE BACTERIA

28. RADIATIONS
TWO TYPES OF RADIATIONS ARE USED:-
1. IONISING RADIATIONS
2. NON – IONISING RADIATIONS
IONISING RADIATIONS:-
• HIGH PENETRATING AND LETHAL TO CELLS
• INCLUDES GAMMA RAYS,X RAYS ETC
• KNOWN TO CAUSE NUCLEIC ACIDS DAMAGE
• GAMMA RADIATIONS ARE USED TO STERILISE SYRINGES,SWABS, CULTURE
PLATES
• COLD STERILISATION- AS THERE IS NO INCREASE IN TEMPERATURE.

29. NON IONISING RADIATION:-
• LOW PENETRATING
• MECHANISM OF ACTION:-
• DENATURATION OF BACTERIAL PROTEINS
• INTERFERING DNA REPLICTAION
• ULTRA VIOLET RADIATIONS:-
• BACTERICIDAL
• USED TO STERILISE ENCLOSED AEAS SUCH AS OT ,LABORATORY ,
INOCULATION
• VEGETATIVE FORMS ARE HIGHLY SUSCEPTIBLE TO UV RADIATIONS
• INFRA RED STERILISATION:-
• USED FOR RAPID MASS STERILISATION OF CATHETERS AND SYRINGES.

30. DISINFECTANTS

31. CHEMICAL METHODS:
• SOME OBJECTS CANNOT WITHSTAND HEAT STERILIZATION/
DISINFECTION
• HENCE CHEMICAL METHODS SHOULD BE CONSIDERED
• BENEFITS:-
• WIDE SPECTRUM OF ACTIVITY
• QUICK ACTION AND HIGH PENETRATION
• MOST STABLE , EVEN IN UNFAVOURABLE ENVIRONMENT
• EASY TO USE
• EASILY AVAILABLE
• NOT MUCH OF TECHNIQUE SENSTIVITY

32. MODE OF ACTION:-
1. PROTEIN COAGULATION
2. DISRUPTION OF CELL MEMBRANE
3. BACTERIOLYSIS
4. ELIMINATION OF SULPHAHYDRAL GROUPS- NECESSARY FOR THE ENZYME
FUNCTION
5. SUBSTRATE COMPTETITION OF ENZYMES.

33. DISINFECTION
• CHEMICAL KILLS ALL
THE MICROBES
EXCEPT SPORES
• REPORTED TO HAVE
ANTISPORICIDAL
ACTION ,IF THE
CONTACT IS
INCREASED.
DISINFECTION
• CHEMICAL KILLS ALL
THE PATHOGEN
INCLUDING
MYCOBACTERIA AND
NON- ENVELOPED
VIRUSES EXCEPT
SPORES.
DISINFECTANTS
CHEMICAL THAT KILLS
ONLY VEGETATIVE
BACTERIA, FUNGI AND
LIPID ENVELOPED
VIRUSES
• GLUTARALDEHYDE
• FORMALDEHYDE
HYDROGEN PEROXIDE
• ALCOHOLS
• PHENOLIC
COMPOUNDS
• IODOPHORES
• QUATERNARY
AMMONIUM
COMPOUNDS
• ACTIVE AGAINST GRAM
POSITIVE
• GRAM NEGATIVE
BACTERIA , SPORES
• EFFECTIVE AGAINST M.
tuberculosis
• AGAINST
MYCOBACTERIA
• VEGETATIVE BACTERIA
• VIRUS AND FUNGI
• NOT EFFECTIVE
AGAINST
MYCOBACTERIA
tuberculosis

34. ALCOHOLS
• ORGANIC MOLECULE ASSEMBLED FROM CARBON, OXYGEN AND
HYDROGEN ATOMS
• ETHYLAND ISOPROPYL ALCOHOL IS USED
• MOA:- 1) DENATURATING AND COAGULATING BACTERIAL PROTEINS
• USED AS SKIN ANTISEPTICS
• EFFECTIVE AT 70% CONC.
• METHYLALCOHOL HAS ANTIFUNGAL PROPERTIES.
• MIXTURE OF ALCOHOLAND WATER- ENHANCES PROTEIN DENATURATION
• AT A CONC. OF 60-80% -POTENT VIRUCIDAL

35. ALDEHYDES:-
 ORGANIC COMPOUND CONTAINING THE GROUP- CHO FORMED BY THE
OXIDATION OF ALCOHOLS.
 FORMALDEHYDE:-
 BROAD SPECTRUM BACTERICIDAL, SPORICIDAL AND VIRUCIDAL
 USED AS AQUEOUS AND GASEOUS FORM
 FORMALIN – 10% CONC. OF FORMALDEHYDE
 MOA :- DENATURATION OF BACTERIAL PROTEINS
 IRREVERSIBLE DAMAGE TO NUCLEIC ACIDS
 USES:- PRESERVATION OF TISSUES
 TO STERILISE BACTERIAL VACCINES

36. GLUTARALDEHYDE
 EFFECTIVE AGAINST BACTERIA, FUNGI AND VIRUSES
 LESS TOXIC
 LESS IRITANT TO EYES AND SKIN THAN FORMALDEHYDE
 COMMERCIALLY KNOWN AS CIDEX
 USED AS 2% BUFFERED SOLUTION.
 APPLICATIONS:-
 STERILISATION OF CYTOSCOPES, ENDOSCOPES AND BRONCHOSCOPES
 TO STERILISE PLASTIC ENDOTRAHEALTUBES , FACE MASKS , ETC.

37. PHENOLS:-
• PRODUCED BY DISTILLATION OF COAL TAR
• OLDEST KNOWN DISINFECTANT
• ALSO KNOWN AS CARBOLIC ACID
MOA:-
 LETHAL IN ACTION
 DAMAGES CELL MEMBRANE , RELEASING CELL CONTENTS
 1% IS BACTERICIDAL
AVAILBILITY:-
HANDWASHES
SOAPS, FLOOR DISINFECTANTS
 TOXIC TO CATS AND NEW BORNS

38. CRESOLS/ LYSOL :-
• STERILISATION OF GLASSWARES, CLEANING FLOORS
• BROAD SPECTRUM IN ACTION
CHLORHEXIDINE:-
• BISBIGUANIDE COMPOUND , HAVING ANIONIC COMPONENT
• BACTERICIDALAT HIGHER CONCENTRATIONS
• 5% CONC. - BACTERICIDAL
• USES:-
• PREOPERATIVE DISINFECTION OF SKIN WOUNDS
• MOUTHWASH
• MARKETED AS SAVLON

39. CHLOROXYLENOL
• PRINCIPAL INGREDIENT IN DETTOL
• LESS TOXIC AND LESS IRRITANT
• HALOGENS:-
THEY ARE PLACED IN PERIODIC TABLE ( NON - METALS)
• CHLORINE:-
• USED IN WATER SUPPLIES ,SWIMMIMG POOLS , FOOD ETC.
• MOA :-
• RELEASE OF FREE CHLORINE
• OXIDIZING AGENT
• USED AS DISINFECTANT AGAINST HIV.

40. IODINE
HALOGEN COMPOUND
• USED AS SKIN DISINFECTANT IN ALCOHOLIC AND AQUEOUS
SOLUTIONS
• COMPOUNDS OF IODINE WITH SURFACE ACTIVE AGENTS -
IODOPHORS
• BACTERICIDAL
• IODOPHORES ARE MORE ACTIVE THAN IODINE
• BETADINE IS EXAMPLE.

41. OXIDISING AGENTS:-
1. HYDROGEN PEROXIDE:-
MOA - BY RELEASE OF FREE RADICALS
USED :- TO DISINFECT CONTACT LENSES
SURGICAL PROSTHESIS
BACTERICIDAL AND SPORICIDAL AT 10-25% CONC.
2. PERACETIC ACID:-
• POTENT THAN HYDROGEN PEROXIDE
• OXIDISING AGENT
• HIGH LEVEL DISINFECTANT
• ALSO USED IN PLASMA STERILISATION

42. PLASMA STERILIZATION:-
 REFERS TO ANY GAS WHICH CONSISTS OF ELECTRON , IONS AND
NEUTRAL PARTICLES
 MIXTURE OF H2O2 AND PERACTEIC ACID TO FORM PLASMA
 RESULTING UV RADIATIONS CAUSES DESTRUCTION OF VEGETATIVE
ORGANISM AND SPORES.
 STERRAD 100S STERILISER AND PLAZLYTE STERILISER -
COMMERCIALLY AVAILABLE

43. STERRAD STERILIZATION:-
• LOW TEMPERATURE STERILIZATION SYSTEM
• HYDROGEN PEROXIDE IS USED
• REDUCES DECONTAMINATION CYCLE
• QUICK TURNAROUND OF URGENT INSTRUMENTS
• NOT TO EXCEED 50 DEGREE CELSIUS
• TIME TAKEN IS 60 MIN.

44. ETHYLENE OXIDE ( ETO)
• COLORLESS LIQUID - B.P. 10.7 DEGREE
• POTENTIAL TOXIC TO HUMANS - MUTAGENIC AND CARCINOGENIC
• INFLAMMABLE
• MOA:- ALKYLATION OF PROTEIN AND NUCLEIC ACIDS
• HIGHLY PENETRATING AND ENTERS THROUGH SOME PLASTICS.
• APPLICATIONS:-
• DISPOSABLE SYRINGES
• DENTAL EQUIPMENTS
• PPE KITS
• UNSUITABLE FOR FUMIGATION

45. FORMALDEHYDE GAS
• FUMIGATION OF OPERATION THEATRES, HEAT – SENSITIVE
EQUIPMENT
• KMNO4 + FORMALIN ( 1000 CUBIC FEET OF SPACE) =
FORMALDEHYDE
• STERILISATION IS ACHIEVED BY THE CONDENSATION OF GAS ON
EXPOSED SURFACES.
• GAS IS NEUTRALIZED WITH AMMONIA( 300ML FOR EVERY LITRE OF
FORMALDEHYDE USED)

46. E- BEAM STERILIZATION
• IRADIATION PROCESS USES HIGH ENERGY ELECTRONS
• TWO TYPES OF E-BEAM ACCELERATOR :-
• ELECTROSTATIC ACCELERATOR- PRODUCES ELECTRONS OF 5 MeV
• MICROWAVE LINEAR ACCELERATOR- PRODUCES ELECTRON OF 10 MeV.
• MOA:-
• AN EVACAUATED TUBE HAS HOT FILAMENT
• PRODUCES HIGH ENERGY ELECTRONS UNDER HIGH POTENTIAL
DIFFERENCE
• SYNCHRONIZED MICROWAVE RADIATION IMPARTS ADDITIONAL ENERGY
ARTICLES ARE PLACED ON HORIZONTAL CONVEYOR BELT
ITS RADIATED FROM BOTH

47. DISINFECTANTS CONCENTRATION
1. ETHYL ALCOHOL 70%
2. GLUTRALADEHYDE 2%
3.LYSOL 2.5%
4.SAVLON ( CHLORHEXIDINE AND
CETRIMIDE)
2%,5%
5.DETTOL(CHLOROXYLENOL) 4%
6.CALCIUM HYPOCHLORITE 14 GM IN 1 LT OF WATER
7.SODIUM HYPOCHLORITE 1%,0.1%
8. BETADINE( IODOPHORE) 2%
RECOMMENDED CONCENTRATIONS OF DISINFECTANTS:-

48. SPAULDING’ S CLASSIFICATION:-
• IN 1968 , DR. E.H. SPAULDING CLASSIFIED MEDICAL, SURGICAL
INSTRUMENTS
• BASED ON THE POTENTIAL OF SPREADING INFECTION.
• CRITICAL
• SEMI CRITICAL
• NON – CRITICAL
• GUIDES US ABOUT THE STERILIZATION PROTOCOL TO BE FOLLOWED.

49. INSTRUMENTS CLASSIFICATION
CRITICAL SEMI –
CRITICAL
NON-
CRITICAL
• INSTRUMENTS
THAT CONTACT
SOFT TISSUES,
BLOOD
• HIGH RISK OF
CROSS
INFECTION
• EX;-
FORCEPS,SCALP
ELS, SCALERS
• INSTRUMENTS
CONTACTING
MUCOUS
MEMBRANE
• NO BLOOD IN
TISSUES
INVOLVEMENT
• MOUTH
MIRROR
• AMALGAM
CONDENSERS
• INSTRUMENTS
CONTACTING THE
SKIN.
• LOW LEVEL OF
CROSS INFECTION
• EX:- DENTAL
CHAIRS, BP CUFF,
X-RAY CONE

50. OSHA GUIDELINES FOR STERILISATION
1. OSHA STANDS FOR - OCCUPATIONAL SAFETY AND HEALTH
ADMINISTRATION
2. STEPS IN STERILIZATION:
1. PRESOAKING
2. CLEANING
3. PACKAGING
4. STERILIZATION
5. HANDLING STERILE INSTRUMENTS
6. STORAGE
7. DISTRIBUTION

51. PRESOAKING :-
• USED INSTRUMENTS ARE PLACED IN ANTI MICROBIAL SOLUTION
• THIS SOFTENS AND LOOSENS THE DEBRIS
CLEANING:-
• MANUAL METHOD OF CLEANING AND MECHANICAL METHODS OF
CLEANING ARE EMPLOYED.
• MANUAL METHOD:-
• UTILITY GLOVES, MASKS ,EYEWEAR AND DISPOSABLE DRAPE TO BE
WORN
• HANDSCRUBBING TO BE DONE , KEEPING IT LOW IN THE SINK
• SYSTEM LOCKED CASETTES - ELIMINATES THE NEED TO SORT ,
HANDLE AND SCRUB EACH INSTRUMENT.

52. MECHANICAL METHOD :-
• ULTRASONIC CLEANING DEVICES
• INSTRUMENT WASHERS
ULTRASONIC CLEANING DEVICES:-
• SOUNDWAVES ARE GENERATED
• BUBBLES FORM OSCILLATION - CAVITATION
• BUBBLES LOOSEN THE DEBRIS FROM THE INSTRUMENTS.
• FUNCTIONING OF THE DEVICE:-
• SET THE TIMER
• TIMING FOR LOOSE INSTRUMENTS- 3 TO 6 MIN
• LID IS CLOSED
• TO AVOID THE RELEASE OF AEROSOLAND SPLATTER FROM THE
DEVICE.

53. INSTRUMENT WASHERS:-
• HIGH VELOCITY HOT WATER AND DETERGENT
• USED IN LARGE ORGANISATIONS SUCH AS HOSPITALS , NURSING
HOMES ,RECENTLY EMPLYOED IN DENTAL SETUPS TOO
• PERSONNEL NEEDS TO PLACE THE INSTRUMENTS IN THE CASETTES/
BASKETS
• DURING CLEANING AND DRYING CYCLE

54. PACKAGING :-
• PRIOR TO STERILIZATION
• INCLUDES WRAP, PAPER POUCHES, NYLON TUBING
• PACKAGES ARE SPECIFICALLY DESIGNED TO ALLOW PENETRATION OF
HEAT , STEAM
• TO SEAL THE STERILIZED INSTRUMENTS INSIDE THE PACKAGE FOR
STERILE STORAGE.
• SUBJECTED TO STERILIZATION CYCLE
• STERILIZATION:-
• DRY HEAT OVEN OR STEAM AUTOCLAVE - AID IN THE STERILIZATION.
• CHEMICAL VAPOUR
• ETO

56. HANDLING STERILE INSTRUMENTS:-
• AVOID DAMPING OF STERILIZED INSTRUMENTS
• TO BE ARRANGED IN THE ORDER OF THEIR APPLICATIONS.
• UV CHAMBERS AND FORMALIN CHAMBERS ARE USED FOR STORAGE

57. TYPES OF AUTOCLAVE:-
1. VACUUM AUTOCLAVE - AIR IS EVACUATED FROM THE METAL CHAMBER
BY VACUUM PUMP.
• STERILIZATION OF HANDPIECES
2. GRAVITY DISPLACEMENT :-SMALL , AUTOMATIC , BENCH TOP
DOWNWARD DISPLACEMENT OF AIR- STEAM ENTERING FROM THE TOP
• TEMP:-134 DEGREE CELSIUS FOR 3-4 MIN AT 207 KPA

58. AUTOCLAVES USED IN DENTISTRY:-
• TYPE N- NON VACUUM STERILIZERS
• PASSIVE DISPLACEMENT WITH STEAM
• UN WRAPPED AND SOLID INSTRUMENTS
• TYPE B ( VACUUM):-
• PROCESS HOLLOW, AIR -RETENTIVE AND PACKAGED LOADS
• INCORPORATE VACUUM STAGE

59. 1. BURS - CARBON, STEEL ,DIAMOND
POINTS
DRY HEAT OVEN 60 DEGREE FOR 1 HR
ETO - 450 -800 MG / L
2. MIRRORS DRY HEAT OVEN , STEAM AUTOCLAVE
CHEMICAL VAPOUR
3. GLASS SLABS STEAM AUTOCLAVE
4. DAPPEN DISHES STEAM AUTOCLAVE
5.HAND INSTRUMENTS- CARBON
STEEL
DRY HEAT OVEN , CHEMICAL VAPOR
6.STAINLESS STEEL AUTOCLAVE , ETO
7.HANDPIECES
ETO , AUTOCLAVE
8.NEEDLE ONE TIME USE , DISCARD
9.ORTHODONTIC PLIERS DRY HEAT OVEN , ETO
10.TISSUE RETRACTION PLUGGERS STEAM AUTOCLAVE , ETO
11. POLISHING WHEELS AND DISKS ETO

60. STERILIZATION IN
PROSTHODONTIC
PRACTICE

61. IMPRESSION TRAYS:-
• PRESOAKED IN ANTIMICROBIAL SOLUTION
• CLEANED USING MECHANICAL OR MANUAL METHOD
• TRAYS ARE DRIED PROPERLY
• PACKED IN STERILIZATION POUCHES
• SUBJECTED TO STERILIZATION CYCLES
• PLACED IN THE AUTOCLAVE AT 121 DEGREE CELSIUS
• AFTER IMPRESSION IS MADE, TRAYS ARE WASHED UNDER
RUNNING TAP WATER

62. HANDPIECES AND BURS
• HIGH RISK FOR CROSS CONTAMINATION
• PROCEDURE:-
• RUN IT FOR 5-10 SEC OVER THE BASIN
• DETACHING IT
• DRYING
• LUBRICATION AND RE-RUN IT FOR 10 SEC.
• PACKED IN THE STERILISING POUCHES
• AUTOCLAVING
• READY TO USE

63. BURS :-
1. ULTRASONIC CLEANERS - TO REMOVE DEBRIS ,BLOOD CLOTS
2. CLEANING SOLUTION - CAN CONTAIN PROTEOLYTIC ENZYMES
3. TEMP -60 DEGREE AT A FREQUENCY OF 60-80 KHZ FOR 15 MIN.
1. DRYING IT
2.CARBON STEEL BURS -DRY HEAT OVEN OR ETO
3.ALDEHYDES & PHENOLIC COMPOUNDS -30 MIN - ADEQUATE
STERILIZATION.

64. FACEBOWS AND BITE FORKS:-
• METAL PARTS - AUTOCLAVABLE
• EARPIECES TO BE REMOVED PRIOR TO STERILIZATION
• DRYING IS ESSENTIAL

65. DENTAL IMPLANTS:-
 TRANSFER ANALOGS
 DRIVERS
 OVERDENTURES
 ABUTMENTS
 TRANSFER SCREWS
 DRILL EXTENSIONS
 PLASTIC HANDLE
 PARALLEL PIN
PROCEDURE:-
1. SOAKING IN LUKEWARM WATER - TO REMOVE BONE DEBRIS
2. PRECLEANING IN ULTRASONIC BATH
3. SCRUB USING NYLON BRUSH
4. FLUSH THE INTERNAL CHANNEL WITH 20ML CLEANING SOLUTION
USING IRRIGATION NEEDLE CONNECTED TO 20 ML SYRINGE
5. LOADED ON INSTRUMENT TRAY TO PLACE IN WASHER
6. PACKING THEM
7. STEAM STERILIZATION FOR 4 MIN. AT 132 DEGREE CELSIUS.

66. DISINFECTION IN
PROSTHODONTIC PRACTICE

67. METHODS OF DISINFECTING IMPRESSIONS
1. SPRAYING
2. IMMERSION
PRIMARY IMPRESSIONS :
ALGINATE IMPRESSIONS:-
 0.5% SODIUM HYPOCHLORITE
 IMMERSION IN IODOPHORES CAN CAUSE DISTORTION - IMBIBTION

68. Agar - reversible hydrocoliod
• stable in immersion in 1: 10 dilution sodium hypochlorite
• 1:2 iodophor
• immersion time is10 min
ZINC- OXIDE EUGENOL:-
• IMMERSION IN 2 % GLUTRALDEHYDE
• IODOPHORS OR CHLORINE COMPOUNDS
IMPRESSION COMPOUND:-
• IMMERSION IN 1:10 DILUTION SODIUM HYPOCHLORITE
• IODOPHOR

69. ELASTOMERIC IMPRESSION MATERIALS:-
• POLYSULPHIDE AND ADDITION SILICONE
• GLUTRALDEHYDE , IODOPHOR , 0.5 % NaOCl to be used
• POLYETHER:-
• SPRAY AND WIPE IN IODOPHOR ,0.5% NaOCl should be used
• prolonged immersion can cause distortion

70. DENTAL CASTS:-
• AS PER ADA RECOMMENDATION:-
• CHLORINE COMPOUNDS
• IODOPHORS
• COMBINATION OF SYNTHETIC PHENOLS
• GLUTRALADEHYDE

71. ACRYLIC DENTURES:-
• SODIUM HYPOCHLORITE IS RECOMMENDED
• IODOPHORS CAN BE USED
• DAMAGE TO HEAT CURE ACRYLIC DENTURE - AFTER 10 MIN OF
IMMERSION IN GLUTARALDEHYDE.
• REMOVABLE CAST PARTIAL DENTURES:-
• IMMERSION IN IODOPHOR OR CHLORINE COMPOUNDS

72. FIXED PROSTHESIS:-
• IMMERSION IN GLUTRALADEHYDE
• COMPLETE METALLIC PROSTHESIS CAN BE STERILIZED
WITH ETO

73. ROTARY INSTRUMENTS - BURS
• DIAMOND AND CARBIDE BURS:-
• SOAKED IN 0.25% GLUTRALDEHYDE FOR 10 MIN
• SCRUBBED WITH BRUSH AND PLACED IN ULTRASONIC BATH
• AUTOCLAVED AFTER CLEANING
• STEEL BURS:-
• CHEMICAL VAPOUR STERILIZATION -USED
• GLASS BEAD STERILIZER AT 230 DEGREE FOR 20-30 SEC

74. IMPLANTS:-
• PRE STERILIZED WITH GAMMA RADIATION
• PLASMA CLEANING IS USED
• RADIO FREQUENCY GLOW DISCHARGE TECHNIQUE CAN ALSO BE
USED
• MATERIAL TO BE CLEANED IS BOMBARDED BY HIGH ENERGENTIC
IONS
• PLASMA GAS FORMS IN A VACUUM CHAMBER
• REMOVES BOTH ORGANIC AND INORGANIC CONTAMINANTS.

75. WASTE MANAGEMENT:-
CATEGORIES OF BIOMEDICAL WASTE
CATEGORIES DESCRIPTION
CATEGORY 1 HUMAN ANATOMICAL WASTE
(TISSUES, ORGANS , BODY PARTS)
CATEGORY 2 ANIMAL WASTE
CATEGORY 3 MICROBIOLOGY AND
BIOTCEHNOLOGY WASTE
CATEGORY 4 WASTE SHARPS (NEEDLES,
SYRINGES, SCALPELS)
CATEGORY 5 DISCARDED MEDICINE AND
CYTOTOXIC DRUGS

76. CATEGORY 6 SOLID WASTE ( ITEMS CONTAMINATED
WITH BLOOD AND FLUID INCLUDING
COTTON DRESSING)
CATEGORY 7 SOLID WASTE ( WATSE GENERATED
FROM DISPOSABLE ITEMS )
CATEGORY 8 LIQUID WASTE ( WASTE
GENERATEDFROM LAB AND WASHING
AND CLEANING)
CATEGORY 9 INCINERATION ASH
CATEGORY 10 CHEICALS USED IN PRODUCTION OF
BIOLOGICAL , CHEMICAL USED IN
DISINFECTION

78. COLOR CODING AND WASTE DISPOSAL
COLOR CONTAINER WASTE
CATEGORY
TREATMENT
OPTIONS
YELLOW PLASTIC BAG 1,2,3,6 INCINERATION
OR DEEP BURIAL
RED PLASTIC BAG 3,6,7 AUTOCLAVING,
MICROWAVING ,
CHEMICAL
TREATMENT
BLUE / WHITE PUNCTURE
PROOF
CONTAINER
4,7 AUTOCLAVING ,
MICROWAVING
SHREDDING
BLACK PLASTIC BAG 5,9,10 DISPOSAL IN
SECURE
LANDFILL

79. COVID
ITS IMPACT ON
PROSTHODONTIC
PRACTICE

80. COVID STANDS FOR CO-CORONA, VI -VIRUS AND D- DISEASE
BELONGS TO FAMILY OF CORONAVIRIDAE
SYMPTOMS:-
• FEBRILE ILLNESS
• DRY COUGH
• TIREDNESS DIFFICULTY IN BREATHING
• CHEST PAIN
• LOSS OF SMELLAND TASTE
WINDOW PERIOD -5-14 DAYS
MODE OF SPREAD:-
• ORO-PHARYNGEAL SECRETIONS
• DROPLET TRANSMISSION
• CONTACT TRANSMISSION

81. IMPACT ON PROSTHODONTIC PRACTICE:
• CONSULTATION IS RISKY
• AEROSOL GENERATING PROCEDURES- MODE OF SPREAD ????
• UNDERSTANDING THE IMPORTANCE OF STERILIZATION
• EMERGENCY TREATMENTS
PRECAUTIONS :-
1. SOCIAL DISTANCING
2. HANDWASHING
3. USAGE OF SANITISERS
4. ISOLATING AND QUARANTINING WITH COVID SCREENING TEST -
SUSPECTED PATENTS
5. STERILIZATION OF THE INSTRUMENTS AND CLINIC
6. USAGE OF MASKS AND FACESHIELD
7. PPE KIT TO BE DULY WORN BY THE DENTIST
8. ENTERTAIN EMERGENCY TREATMENT ONLY
9. USAGE OF DISPOSAL INSTRUMENTS.

83. CONCLUSION:-
• A STEADY INCREASE OF TRANSMISSIBLE DISEASE OVER THE
RECENT YEARS HAVE CREATED GLOBAL CONCERN
• HENCE ITS IMPACT ON TREATMENT MODALITIES OF ALL THE
PRACTIONERS.
• EMPHASIZING THE IMPORTANCE OF STERILIZATION AND
DISINFECTION IN THIS COVID ERA IS A MUST
• UPGRADING AND STRENTHENING THE KNOWLEDGE IN
STERILISATION IS NEED OF THE HOUR.

84. REFERENCES:-
 TEXTBOOK OF MICROBIOLOGY , 7 TH EDITION-
ANANTHANARAYAN
 TEXTBOOK OF MICROBIOLOGY -C. P. BAVEJA
 AN INVITRO STUDY TO EVALUATE THE EFFECT OF
DIMENSIONALOF ELASTOMERS DURING COLD
STERILISATION: dhanya kumar bh, nandeeshwardb.J indian
prosthodont soc 2015;15:131-7
 Council on scientific affairs and council on dental practice: infection
control recommendations for the dental practice and the dental
laboratory
- JAm Dent Assoc1996:127:672-680
 infection control protocol in prosthodontics- A REVIEW
---- Intl Journal of scientific research -march 2019

85. THANK YOU