STERILIZATION_AND_DISINFECTIONAND COVID 19 protocol .pptx

All about sterilisation

1. MODERATED BY Dr SUPRABHA RATHEE BY – Dr SIDDHANT PAL(1 st year) MDS

2. 5 (OSHA) UNIVERSAL PROTOCOL 6 SPAULDING’S CLASSIFICATION 3 AUTOCLAVE 4 RADIATION Topic’s Contents Topics 1 INTRODUCTION 2 STERILIZATION 8 DISINFECTION IN PROSTHO 5 DISINFECTION 7 STERILIZATIN IN PROSTHO 10 (CDC) COVID-19 PROTOCOL 11 ROBOT IN STERILIZATON AND DISINFECTION 12 REFRENCES INTRODUCTION

3. One of the primary responsibilities of dental healthcare professionals is to create a safe and comfortable environment for their patients. Keeping this in view, the International Organization of Standardization (ISO) , American Dental Association (ADA), Indian Dental Association (IDA)and the Centers for Disease Control (CDC) have developed measures to prevent cross-infection among dental patients. This involves thorough cleaning and sterilization of all types of dental instruments, each time they are used on a patient. INTRODUCTION Important Terminologies

4. Cleaning: It is an essential process which is performed before sterilization and disinfection of dental instruments. This involves cleaning all surfaces of dental instruments to remove blood, microbes, and debris, and to prepare instruments for the dental sterilization process. Cleaning of instruments is usually performed with water or detergents. Disinfection : It is a process in which all microbes are removed, except bacterial spores. Disinfection of dental instruments is usually performed with liquid disinfectants. Sterilization : It refers to any process that removes, kills, or deactivates all forms of life and other biological agents like prions present in a specific surface, object or fluid, for example food or biological culture media. A/C to GPT10 : The process of completely eliminating microbial viability. Asepsis : T he prevention of contact with microorganisms. CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2018 Important Terminologies Organisms can be transmitted in dental settings through

5. Organisms can be transmitted in dental settings through Direct contact with blood, oral fluids, or other patient materials 2) Indirect contact with contaminated objects 3) Contact of conjunctival , nasal, or oral mucosa with droplets 4) Inhalation of airborne micro organisms that can remain suspended in the air for long periods. 5) Transmission of several diseases like Hepatitis , HIV , Herpes simplex virus . CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008

6. CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008 Presoaking :  A presoaking solution (phenolic compounds) prevents drying of debris, helps to dissolve or soften organic debris and sometimes helps in microbial killing. Cleaning :  Cleaning can be done either by hand, scrubbing or with the use of ultrasonic devices. Corrosion control :  Instruments must be dried prior to sterilization to decrease chances of corrosion. Packaging :  The instruments can be packed individually or in small groups and distributed on sterile or disposable disinfected trays for use at chair side Sterilization Storage :  Sterile packs and trays should be kept in dry, low dust, low traffic areas away from sinks and sewer of water pipes, at least a few inches above the floor. Distribution PROCESS BEFORE AND AFTER STERILIZATION

7. PROCESS BEFORE AND AFTER STERLIZATION CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008 Presoaking :  A presoaking solution (phenolic compounds) prevents drying of debris, helps to dissolve or soften organic debris and sometimes helps in microbial killing. Cleaning :  Cleaning can be done either by hand, scrubbing or with the use of ultrasonic devices. Corrosion control :  Instruments must be dried prior to sterilization to decrease chances of corrosion. Packaging :  The instruments can be packed individually or in small groups and distributed on sterile or disposable disinfected trays for use at chair side Sterilization Storage :  Sterile packs and trays should be kept in dry, low dust, low traffic areas away from sinks and sewer of water pipes, at least a few inches above the floor. Distribution

8. PROCESS BEFORE AND AFTER STERILIZATION CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008 Presoaking :  A presoaking solution (phenolic compounds) prevents drying of debris, helps to dissolve or soften organic debris and sometimes helps in microbial killing. Cleaning :  Cleaning can be done either by hand, scrubbing or with the use of ultrasonic devices. Corrosion control :  Instruments must be dried prior to sterilization to decrease chances of corrosion. Packaging :  The instruments can be packed individually or in small groups and distributed on sterile or disposable disinfected trays for use at chair side Sterilization Storage :  Sterile packs and trays should be kept in dry, low dust, low traffic areas away from sinks and sewer of water pipes, at least a few inches above the floor. Distribution

9. PROCESS BEFORE AND AFTER STERILIZATION CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008 Presoaking :  A presoaking solution (phenolic compounds) prevents drying of debris, helps to dissolve or soften organic debris and sometimes helps in microbial killing. Cleaning :  Cleaning can be done either by hand, scrubbing or with the use of ultrasonic devices. Corrosion control :  Instruments must be dried prior to sterilization to decrease chances of corrosion. Packaging :  The instruments can be packed individually or in small groups and distributed on sterile or disposable disinfected trays for use at chair side Sterilization Storage :  Sterile packs and trays should be kept in dry, low dust, low traffic areas away from sinks and sewer of water pipes, at least a few inches above the floor. Distribution

10. PROCES BEFORE AND AFTER STERILIZATION CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008 Presoaking :  A presoaking solution (phenolic compounds) prevents drying of debris, helps to dissolve or soften organic debris and sometimes helps in microbial killing. Cleaning :  Cleaning can be done either by hand, scrubbing or with the use of ultrasonic devices. Corrosion control :  Instruments must be dried prior to sterilization to decrease chances of corrosion. Packaging :  The instruments can be packed individually or in small groups and distributed on sterile or disposable disinfected trays for use at chair side Sterilization Storage :  Sterile packs and trays should be kept in dry, low dust, low traffic areas away from sinks and sewer of water pipes, at least a few inches above the floor. Distribution

11. CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008 Presoaking :  A presoaking solution (phenolic compounds) prevents drying of debris, helps to dissolve or soften organic debris and sometimes helps in microbial killing. Cleaning :  Cleaning can be done either by hand, scrubbing or with the use of ultrasonic devices. Corrosion control :  Instruments must be dried prior to sterilization to decrease chances of corrosion. Packaging :  The instruments can be packed individually or in small groups and distributed on sterile or disposable disinfected trays for use at chair side Sterilization \ disinfection Storage :  Sterile packs and trays should be kept in dry, low dust, low traffic areas away from sinks and sewer of water pipes, at least a few inches above the floor. Distribution PROCESS BEFORE AND AFTER OF STERILIZATION

12. PROCESS BEFORE AND AFTER OF STERILIZATION CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008

13. HISTORY ABOUT STERILIZATION Louis Pasteur was the first scientist to use sterilization, he developed steam sterilization , hot air oven and autoclave. Joseph lister used the sterilization concept of louis Pasteur and advocated antiseptic technique in surgery and hence called as “ FATHER OF ANTISEPTIC SURGERY ”. CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008

14. PHYSICAL STERILIZATION CHEMICAL STERILIZATION MECHANICAL STERILIZATION METHODS OF STERILIZATION CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008

15. SUNLIGHT DRYING HEAT -MOIST - DRY RADIATION PHYSICAL CHEMICAL MECHANICAL METHODS OF STERILIZATION CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008 ALCOHOL ALDEHYDES HEAVY METALS( DYES ,LYSOL) GLUTARALDEHYDE FORMALDEHYDE ETHYLENE OXIDE SCRUBBING SEDIMENTATION FILTRATION

16. 1) Sun light - It is responsible for spontaneous sterilization in natural conditions.  In tropical countries , the sunlight is more effective in killing germs due to combination of ultraviolet rays and heat. By killing bacteria suspended in water, sunlight provides natural method of disinfection of tanks and lakes. 2 ) Drying - Moisture is essential for growth of bacteria. Drying in air has dangerous effect on many bacteria.  However, spores are unaffected. Therefore, it is not satisfactory method for sterilization.

17. 4) Incineration :- 1.Incineration is a waste treatment process that involves of organic substances contained in waste materials. 2. This method also burns any organism to ash. It is used to sterilize medical and other biohazardous waste before it is discarded with non-hazardous waste. 3) Flaming :- This is a method of passing article over a flame, but not heating it to redness. Use- scalpels, mouth of test tubes, flask, glass slide & coverslips 2) Red hot sterilization :- - Sterilization by holding them in Bunsen flame till they become red hot. It use for bacteriological loops, straight wires, tips of forceps & spatulas 1) Hot air oven:- a.Hot air ovens are electrical devices which use dry heat to sterilize. b. They were originally developed by pasteur . c. Generally, they can be operated from 50 to 300 °C, using a thermostat to control the temperature. d. An air circulating fan helps in uniform distribution of the heat. Dry heat sterilization also have 4 type:- 1) Hot air oven 2) Red hot sterilization 3) Flaming 4) incineration A)Dry heat sterilization- 1. In dry heat sterilization, dry heat is used for sterilizing different materials. 2.Heated air or fire is used in this process. As compared to the moist heat sterilization, the temperature is higher. 3.The temp. is maintained for almost an hour to kill the most difficult of the resistant spores. Heat sterilization- it has also two type

18. 2) Red hot sterilization :- - Sterilization by holding them in Bunsen flame till they become red hot. It use for bacteriological loops, straight wires, tips of forceps & spatulas 1) Hot air oven:- A Hot air ovens are electrical devices which use dry heat to sterilize. b. They were originally developed by Pasteur. c. Generally, they can be operated from 50 to 300 °C, using a thermostat to control the temperature. d. An air circulating fan helps in uniform distribution of the heat . Eg glassware, flasks Dry heat sterilization also have 4 type:- 1) Hot air oven 2) Red hot sterilization 3) Flaming 4) incineration A)Dry heat sterilization- 1. In dry heat sterilization, dry heat is used for sterilizing different materials. 2.Heated air or fire is used in this process . As compared to the moist heat sterilization, the temperature is higher. 3.The temp. is maintained for almost an hour to kill the most difficult of the resistant spores. Heat sterilization- it has also two type

19. 3) Incineration :- 1.Incineration is a waste treatment process that involves of organic substances contained in waste materials. 2. This method also burns any organism to ash. It is used to sterilize medical and other biohazardous waste before it is discarded with non-hazardous waste. 4 ) Flaming :- This is a method of passing article over a flame, but not heating it to redness. Use- scalpels, mouth of test tubes, flask, glass slide & coverslips

20. CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008

21. CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008

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23. 01 02 03 04 INCINERATION FLAMING BOILING INSPISSATION IMAGES 05 PASTEURIZATION

24. Different methods of sterilization are used in dentistry, based on required depth of sterilization as well as the type of dental material CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008 1. Sterilization using steam autoclave This is the most effective and most commonly used method of sterilization in dental practice. Instruments in an autoclave are sterilized at 121ᵒ C for 15 minutes and 15 pounds pressure. 2 . Dry Heat Ovens These are electrical devices, which use dry heat to sterilize dental instruments. Dry heat ovens are used to sterilize those instruments which do not get burnt during heating, such as glass slabs or powders.

25. Different methods of sterilization are used in dentistry, based on required depth of sterilization as well as the type of dental material CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008

26. 3. Chemical Vapor Sterilization During chemical vapor sterilization, a mixture of various chemicals such as alcohol, ketones, formaldehyde , and water are heated under pressure to form a sterilization gas. A typical sterilization procedure requires 20 minutes at 270ᵒF, under 20 psi pressure to complete. 4. Cold Sterilization This type sterilization is used on heat-sensitive dental instruments . Solutions such as glutaraldehyde or Sodium hypochlorite may be used for this purpose. CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008

27. 3. Chemical Vapor Sterilization During chemical vapor sterilization, a mixture of various chemicals such as alcohol, ketones, formaldehyde, and water are heated under pressure to form a sterilization gas. A typical sterilization procedure requires 20 minutes at 270ᵒF, under 20 psi pressure to complete. 4. Cold Sterilization This type sterilization is used on heat-sensitive dental instruments. Solutions such as glutaraldehyde or Sodium hypochlorite may be used for this purpose. CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008

28. Autoclave The autoclave is a sealed device that kills microorganisms using saturated steam under pressure. The use of moist heat facilitates the killing of all microorganisms, including heat-resistant endospores which is achieved by heating the materials inside the device at temperatures above the boiling point of water. CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008

29. Autoclave The autoclave is a sealed device that kills microorganisms using saturated steam under pressure. The use of moist heat facilitates the killing of all microorganisms, including heat-resistant endospores which is achieved by heating the materials inside the device at temperatures above the boiling point of water. CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008

30. THE STERILIZATION CYCLE The sterilization cycle can be divided into three periods: the heating-up period , the holding period and the cooling period . 1. Removal of air by a vacuum pump while the chamber is heated to the selected temperature. 2. Holding the load, which is sterilized, for the appropriate period at the selected temperature and pressure. 3. Drying the load to its original condition by a partial vacuum 4. Restoration of the chamber to atmospheric pressure by rapid exhaustion of steam. CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008

31. TYPES OF AUTOCLAVE Vacuum autoclaves : in which air is evacuated from a metal chamber by vacuum pump. These vacuum autoclaves are more desirable for routine dentistry than the gravity displacement type for the sterilization of hollow devices such as dental handpieces. Gravity displacement autoclaves : are small, automatic bench-top autoclaves. They work on the principle of downward displacement of air as a consequence of steam entering at the top of the chamber. CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008

32. TYPES OF AUTOCLAVE Autoclaves used in dentistry Type N : air removal in type N sterilizers is achieved by passive displacement with steam. They are non-vacuum sterilizers designed for non-wrapped solid instruments . Type B (vacuum) : these sterilizers incorporate a vacuum stage and are designed to reprocess load types such as hollow, air-retentive and packaged loads. CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008

33. Cp baveja 5 th edition

34. Glass Bead Sterilizer Glass bead sterilization uses small glass beads(1.2-1.5 mm diameter) and high temperature ( 210 – 230’C) for 10-30 sec to inactivate microorganisms . Use- endodontic files , burs Disadvantage- no uniform heat CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008

35. Glass Bead Sterilizer Glass bead sterilization uses small glass beads(1.2-1.5 mm diameter) and high temperature ( 210 – 230’C) for 10-30 sec to inactivate microorganisms. Use- endodontic files , burs Disadvantage- no uniform heat CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008

36. Sterilization Monitoring: Types of Indicators CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008

37. Mechanical Monitoring CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008

38. CHEMICAL MONITERING CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008

39. B IOLOGICAL MONITORING CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008 Assess sterilization process directly by killing known highly resistant microorganisms. Use biological indicators (spore tests) at least weekly.

40. B IOLOGICAL MONITORING CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008 Assess sterilization process directly by killing known highly resistant microorganisms. Use biological indicators (spore tests) at least weekly.

41. RADIATION C p baveja 5 th edition

42. 1.Sterilization of operating theatre 2.Sterilization of the interiors of biological safety cabinets Used for sterilization of an article that does not stand heat as rubber catheters, gloves, plastic syringes. C p baveja 5 th edition

43. 1.Sterilization of operating theatre 2.Sterilization of the interiors of biological safety cabinets Used for sterilization of an article that does not stand heat as rubber catheters, gloves, plastic syringes.

44. ULTRASONIC VIBRATORS: Used instruments are soaked into a container containing 70% isopropyl alcohol for removal of organic debris. After removing instruments rinse thoroughly in warm water to remove all chemicals. As a final step insert the instruments into the ultrasonic vibrator and operate for 30 minutes , after which sterile instruments are rendered. Ultrasonic vibrators are generally used for non-critical items .

45. ULTRASONIC VIBRATORS: Used instruments are soaked into a container containing 70% isopropyl alcohol for removal of organic debris. After removing instruments rinse thoroughly in warm water to remove all chemicals. As a final step insert the instruments into the ultrasonic vibrator and operate for 30 minutes, after which sterile instruments are rendered. Ultrasonic vibrators are generally used for non-critical items.

46. Recent advances in sterilization Plasma sterilization: Plasma is known as the fourth state of matter and consists of ions, electrons or neutral particles. A radio frequency energy is applied to create an electromagnetic field. Into this, hydrogen peroxide vapors are introduced which generates a state of plasma containing free radicals of hydrogen and oxygen . This state renders the articles sterile by denaturing all microorganisms . Arthroscopes , urethroscopes , etc., are sterilized by plasma sterilization.

47. PLASMA STERILIZATION START 03 01 04 02 Low-Temperature Hydrogen Peroxide Gas Plasma (LTHPGP A Gas plasma sterilization technology based of Plasma was patented in 1987, and marketed in US 1993. C • Gas Plasma (vaporized hydrogen peroxide) is a relatively new option that can provide low heat sterility cycles with none of the off-gassing concerns present with EtO . B The Vacuum Phase : The chamber is evacuated, reducing internal pressure in preparation for the subsequent reaction. STEP-1

48. 08 06 05 07 The Injection Phase : A measured amount of liquid peroxide is injected into the chamber, evaporating the aqueous hydrogen peroxide solution and dispersing it into the chamber, where it kills bacteria on any surface it can reach. 2 The Plasma Phase : electromagnetic field is created in which the hydrogen peroxide vapor breaks apart , producing a low-temperature plasma cloud that contains ultraviolet light and free radicals . 4 The Diffusion Phase : The hydrogen peroxide vapor permeates the chamber, exposing all load surfaces to the Sterilant and rapidly sterilizes devices and materials without leaving any toxic residues. At the completion of this phase, the chamber pressure is reduced and the plasma discharge is initiated. 3 Following the reaction, the activated components lose their high energy and recombine to form oxygen and water . AFTER COMPLETE PHASE 10 09 The Vent Phase The chamber is vented to equalize the pressure enabling the chamber door to be opened. There is no need for aeration or cool-down . Devices are ready for immediate use . E Phases 1, 2, and 3 are then run a second time for added efficacy. This built-in reprocessing assures optimal sterilization for even the most difficult-to-sterilize devices. D

49. Pulsed light sterilization Pulsed light sterilization • Pulsed light is a non-thermal sterilization method that uses brief intense pulses or flashes of white light to kill microorganisms . • The basic principle of Pulsed Light sterilization is to destruct microorganisms with short intense light flashes generated by Xenon lamps.

50. DISINFECTION (CONC) FORMALDEHYDE 3% aq 30 min FORMALDEHYDE 8% aq 10hr FORMALDEHYDE 8% (70% 10hr alcohol) GLUTARALDEHYDE 2% alk 30 min GLUTARALDEHYDE 2% aq 10hr CHLORINE COMPOUND 1% 30 min POTENCY Intermediate High High Intermediate High intermediate TIME BIOLOGICAL ACTIVITY OF CERTAIN DISINFECTANT Rudd and morrow vol 1 chapter 18

51. Ethyl alcohol (ethanol) and isopropyl alcohol most frequently used . They are used mainly as skin antiseptics at a concentration of 60- 90% in water. They act by denaturing bacterial proteins. They have no action on spores Aldehydes Formaldehyde gas is used for sterilizing instruments , heat sensitive catheters and for fumigating wards, isolation rooms and laboratories. It comes with commercial name of CIDEX William A. Rutala and David J. Weber; Disinfection and Sterilization in Health Care Facilities

52. Glutaraldehyde Has an action similar to that of formaldehyde. It is especially effective against the tubercle bacilli, fungi and viruses . It has no deleterious effect on cement or lenses of instruments. Hypochlorous acid It is generated from the reverse reaction of sodium hypochlorite and hydrogen peroxide . It has bactericidal activity against common pathogenic organisms . Chlorine Have been used as disinfectants over time. They are markedly bactericidal and virucidal.

53. Iodine in an aqueous and alcoholic solution has been widely used as a skin disinfectant. It is bactericidal, with moderate action against spores. It is active against the tubercle bacteria and viruses. Phenols Commonly used compounds are Lysol and cresol Phenols is widely used as disinfectants in hospital. Acts by cell membrane damage thus releasing cell contents and cause lysis. They are not readily inactivated by the presence of organic matter; hence, they are good general disinfectants. Chlorhexidine a relatively non-toxic skin antiseptic and wound dressing. They are active against most Gram-positive organisms and fairly effective against Gram-negative bacteria . William A. Rutala and David J. Weber; Disinfection and Sterilization in Health Care Facilities

54. Gases Ethylene oxide: This is a colorless liquid highly penetrating at normal temperature and pressure. It diffuses through many types of porous materials and readily penetrates some plastics. It is unsuitable for fumigating rooms because of its explosive property. Formaldehyde gas: This is employed for fumigation of operation theatres and other rooms. William A. Rutala and David J. Weber; Disinfection and Sterilization in Health Care Facilities

55. kills all microbial pathogens except large numbers of spores . It may have some activity against a smaller number of spores if the contact time is increased. For example, glutaraldehyde and hydrogen peroxide . High-level disinfectant: kills all microbial pathogens including mycobacteria and non-enveloped viruses except spores . For example, alcohol, phenolic compounds and iodophors. Intermediate-level disinfectant kills only vegetative bacteria, fungi and lipid enveloped viruses. For example, quaternary ammonium compound. Eg. hexadecyltrimethylammonium ( 'cetrimide' ), chlorhexidine, and benzalkonium chloride LOW LEVEL DISINFECTANT LEVEL OF DISINFECTION

56. CP Baweja 5 TH edition

57. Instrument classification based on potential to spread infection (Spaulding's classification)

58. Categories of Patient-Care Items Three categories: Critical. Semicritical. Noncritical. Based on intended use and the potential risk of disease transmission

59. Critical Items Penetrate soft tissue or contact bone, enter into or contact the vascular system or other normally sterile tissue. Greatest risk of transmitting infection. Must be heat sterilized between use, or sterile single-use, disposable devices must be used. Examples: surgical instruments and periodontal scalers .

60. Semi-critical Items Contact mucous membranes or non-intact skin (e.g., exposed skin that is chapped, abraded, or has dermatitis). Lower risk of transmission. Should be heat sterilized or high-level disinfected. Examples: mouth mirrors, amalgam condensers, and reusable impression trays.

61. Non - critical Items Contact intact skin. Barrier protect or clean and disinfect (if visibly soiled) using a low to intermediate-level (i.e., tuberculocidal) disinfectant. Examples: x-ray head or cone, facebows, blood pressure cuff .

62. Special Considerations—Dental Handpieces Follow manufacturer’s instructions to safely reprocess dental handpieces and accessories (e.g., low-speed motor, reusable prophylaxis angles). Clean and heat sterilize between patient uses. Special Considerations—Digital Sensors Follow manufacturer’s instructions to safely reprocess digital radiography equipment. Ideally, barrier protection should be used, followed by cleaning and heat sterilization or high-level disinfection between patients.

63. Single-Use (Disposable) Devices Intended for use on one patient during a single procedure. Usually not heat-tolerant. Cannot be reliably cleaned. Do NOT reprocess. Examples: syringe needles, prophylaxis cups, and plastic orthodontic brackets .

64. Environmental Infection Control Clinical Contact Surfaces can be directly contaminated from patient materials either by direct spray or spatter generated during dental procedures or by contact with gloved hands. • light handles • switches, • dental radiograph equipment, • dental chairside computers, • reusable containers of dental materials, • drawer handles, • faucet handles, • countertops, • pens, • telephones, • doorknobs. http:// Abichandani S, Nadiger R. Cross contamination in dentistry: A comprehensive overview. Journal of Education and Ethics in Dentistry. 2012 Jan 1;2(1):3.

65. Reducing aerosols One study found that ultrasonic instrumentation can transmit 100,000 microbes per cubic foot up to six feet, and, if improper air current is present, microbes can last anywhere from 35 minutes to 17 hours . Preoperative mouth rinses with suitable disinfectant help reduce infectious load use of high-velocity air evacuation  by flushing waterlines at the beginning of the workday and between each patient using air purifications systems (high efficiency particulate air- HEPA filters) use of personal barrier protection such as masks, gloves and eye protection CP BAWEJA 5 TH EDITION Aerosols are differentiated into: spatter (> 50 µm) droplet (≤ 50 µm) droplet nuclei (≤ 10 µm) In dental settings, 90% of the aerosols produced are extremely small (< 5 µm).

66. Cross contamination in Prosthodontics CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008 Impressions, casts, impression trays, record bases, occlusal rims, articulators and dental prostheses can all transmit pathogenic microorganisms It is a severe problem that involves health professionals, especially in Prosthodontics Microorganisms capable of causing cross contamination are present in human blood. Contact with blood or saliva mixed with blood may transmit pathogenic microorganisms. Connor C. Cross-contamination control in prosthodontic practice. International Journal of Prosthodontics. 1991 Jul 1;4(4).

67. Cross contamination in Prosthodontics CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008 Streptococcus and Staphylococcus species, Bacillus species, Enterobacter species, Hepatitis virus, Herpes simplex and human immunodeficiency virus (HIV) are among the microorganisms found frequently in blood and saliva. Keeping this in mind, each armamentarium used in a prosthodontic setting should be sterilized or disinfected. Connor C. Cross-contamination control in prosthodontic practice. International Journal of Prosthodontics. 1991 Jul 1;4(4).

68. Sterilization of Diagnostic Instruments Dry the diagnostic instrument with help of wipes. Only absolutely dry instruments must be placed in the sterilizer, in order to avoid calciferous deposits and/or water spots. Instruments are autoclaved at 121° C. Rudd and morrow vol 1 chapter 18

69. Sterilization of Impression Trays After the impression has been removed from the metallic impression trays the trays are washed with running water and are made free from the particles adhering to it. The trays are the properly dried and placed in autoclave for sterilization at 121° C. RUDD AND MORROW VOL 1 CHAPTER 18 TRAYS

70. After the impression has been removed from the metallic impression trays the trays are washed with running water and are made free from the particles adhering to it. The trays are the properly dried and placed in autoclave for sterilization at 121° C. Sterilization of Impression Trays

71. STERILIZATION OF HANDPIECE Moist heat using saturated water vapor's (autoclave) offers the best results as regards the sterilization of handpieces in the short time.

72. STERILIZATION OF HANDPIECE Moist heat using saturated water vapor's (autoclave) offers the best results as regards the sterilization of handpieces in the short time .

73. Sterilization of Burs Step 1. meticulous cleaning to remove tooth debris, residues of dental materials, blood clots or a paste-like mixture with saliva of all the above. Step 2. After removal from the ultrasonic bath, burs must be dried using absorbent paper and hot air. Step 3. They must then be placed in an appropriate device for sterilization, depending on the material they are made of. The most widely accepted cleaning method for burs and other micro instruments are ultrasonic devices at a temperature of about 60°C, burs vibrate at a frequency of 60-80 kHz for at least 15 minutes. Rudd and morrow vol 1 chapter 18

74. Sterilization of Burs Rudd and morrow 2008 Step 1. meticulous cleaning to remove tooth debris, residues of dental materials, blood clots or a paste-like mixture with saliva of all the above. Step 2. After removal from the ultrasonic bath, burs must be dried using absorbent paper and hot air. Step 3. They must then be placed in an appropriate device for sterilization, depending on the material they are made of. The most widely accepted cleaning method for burs and other micro instruments are ultrasonic devices at a temperature of about 60°C, burs vibrate at a frequency of 60-80 kHz for at least 15 minutes.

75. More specifically : 1) Burs made of common carbon steel should not be placed in the autoclave because they will undergo oxidation. 2) Dry heat ovens, ovens for chemical vapor sterilization and ethylene oxide ovens are suitable for sterilizing all types of burs . However, it may seriously damage the cutting edge of the burs. 3) Using various aldehydes and phenols for at least 30 minutes offers adequate sterilization while after 10 hours chemical sterilization is achieved . Nevertheless, they may damage the integrity of rotating cutting instruments. Rudd and morrow vol 1 chapter 18

76. Sterilization of Facebows & Bite forks Parts of facebow which are made of metal can be sterilized in autoclave. It is important to note that earpieces of facebow be removed before sterilization. Before facebow and bite fork is kept in autoclave it is necessary to wipe it with dry cloth. Facebow and bite fork can be autoclaved at 121⁰C. CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008

77. Sterilization of Facebows & Bite forks Parts of facebow which are made of metal can be sterilized in autoclave. It is important to note that earpieces of facebow be removed before sterilization. Before facebow and bite fork is kept in autoclave it is necessary to wipe it with dry cloth. Facebow and bite fork can be autoclaved at 121⁰C.

78. PREVENTING CROSS CONTAMINATION DURING IMPLANT PLACEMENT Proper sterilization should be ensured. Unnecessary items should be removed from the operating area. Proper sanitization of the area should be done. Along with the dental professionals assistants should also follow the protocol. Proper antibiotic prophylaxis should be done. Handling of implant should be done.

79. Rudd and murrow , 2008 Dental chair is sterilized by rubbing the inconspicuous area first by 70% isopropyl alcohol. If there is no discoloration seen in that area then proceeded with rubbing it gently for 6 minutes. Rubber bowls and other rubber items are autoclaved . Dental office is sterilized with fumigation by 2% glutaraldehyde

80. DISINFECTION IN PROSTHODONTIC PRACTICE

81. Methods Of Disinfecting Impressions 1-Spraying 2-Immersion 3- Other UV light RUDD AND MORROW VOL 1 CHAPTER 18

82. Different Dental Impressions Alginate Impressions: can be done with 0.5% sodium hypochlorite. Iodophors immersion disinfection for prolonged periods will cause distortion due to imbibition. Agar- Reversible Hydrocolloid: Found to be stable when immersed in 1:10 dilution sodium hypochlorite or 1:2 iodophor. Recommended immersion time is 10 minutes. Connor c cross contamination

83. Zinc Oxide Eugenol Immersion : It can be disinfected in 2% glutaraldehyde , Iodophors or Chlorine compounds. Adverse effect have been reported on ZOE immersed for 16 hours in diluted hypochlorite . Impression Compound : Immersion in 1:10 dilution sodium hypochlorite or iodophor for specified time period has been found to be useful for disinfecting impression compound impression. Connor c cross contamination

84. Polysulphide and Addition Silicone: Glutaraldehyde , Iodophor,0.5% sodium hypochlorite should be used for its disinfection. Polyether: Spraying in iodophor , 0.5% Sodium hypochlorite should be used. Prolonged immersion causes distortion. Polyether shows dimensional changes on immersion in 2% glutaraldehyde . Connor c cross contamination

85. Polysulphide and Addition Silicone : Glutaraldehyde , Iodophor,0.5% sodium hypochlorite should be used for its disinfection. Polyether: Spraying in iodophor , 0.5% Sodium hypochlorite should be used. Prolonged immersion causes distortion . Polyether shows dimensional changes on immersion in 2% glutaraldehyde . Rudd and murrow

86. Disinfection Of Wax Bites & Occlusal Rims Wax rims and wax bites should be disinfected by the spray wipe spray method using an iodophor . Rinse & spray may be more appropriate for wax bites. After the second spray, they can be enclosed in a sealed plaster bag for the recommended time. These items should be rinsed again after disinfection to remove any residual disinfectant. OCCLUSAL RIMS

87. Disinfection Of Wax Bites & Occlusal Rims Wax rims and wax bites should be disinfected by the spray wipe spray method using an iodophor . Rinse & spray may be more appropriate for wax bites. After the second spray, they can be enclosed in a sealed plaster bag for the recommended time. These items should be rinsed again after disinfection to remove any residual disinfectant. Rudd and morrow vol1 chapter 18

88. Disinfection Of Bite Registrations These registrations can be disinfected, using the rinse spray rinse technique, with most hospital level tuberculocidal disinfectants used as sprays (chlorine compounds should not be applied to ZOE). After disinfection, the registration should be rinsed again to remove residual disinfectant . Rudd and morrow vol1 chapter 18

89. Disinfection Of Bite Registrations These registrations can be disinfected, using the rinse spray rinse technique, with most hospital level tuberculocidal disinfectants used as sprays ( chlorine compounds should not be applied to ZOE). After disinfection, the registration should be rinsed again to remove residual disinfectant .

90. Disinfection of Dental Casts ADA recommends that stone casts be disinfected by the spraying until wet or immersing in a 1:10 dilution of sodium hypochlorite or an iodophor solution. Casts to be disinfected should be fully set (i.e. stored for at least 24 hours ). Microwave irradiation of casts for 5 mins at 900W gives high level disinfection of the gypsum casts Rudd and morrow vol1 chapter 18

91. Disinfection of Dental Casts ADA recommends that stone casts be disinfected by the spraying until wet or immersing in a 1:10 dilution of sodium hypochlorite or an iodophor solution. Casts to be disinfected should be fully set (i.e. stored for at least 24 hours). Microwave irradiation of casts for 5 mins at 900W gives high level disinfection of the gypsum casts

92. Disinfection Of Custom acrylic resin impression trays Custom acrylic resin impression trays should be disinfected by spraying with surface disinfectants or immersing in either 1:2 iodophor or 1:10 sodium hypochlorite. They should be rinsed thoroughly to remove any residual disinfectant and allowed to dry fully before use. Rudd and morrow vol1 chapter 18

93. Disinfection Of Custom acrylic resin impression trays Custom acrylic resin impression trays should be disinfected by spraying with surface disinfectants or immersing in either 1:2 iodophor or 1:10 sodium hypochlorite. They should be rinsed thoroughly to remove any residual disinfectant and allowed to dry fully before use.

94. Rubber items , bowls Hand piece Burs 1.Air rotor burs 2.diamond stone bur Stainless steel Hand instrument Facebow fork Shade guide Ethylene oxide , (damaged by dry heat) Steam , dry heat , chemical vapor , ethylene oxide Moist heat , chemical vapor Ethylene oxide , moist heat Autoclave chemical vapor , dry heat Ethylene oxide Autoclave Iodophor , wipe with water or alcohol MATERIAL METHORD OF STERILIZATION Rudd and morrow vol 1 chapter 18

95. OSHA protocol OSHA stands for Occupational Safety and Health Administration. Universal Precautions prevents the spread of Blood borne diseases These standard helps prevent exposure to HIV and HBV Blood borne Pathogens Standard covers the steps employers and employees must take to prevent exposure to possibly Infected blood or other body fluids. Rudd and morrow vol1 chapter 18

96. OSHA protocol HIV and HBV Are Spread Through Direct, Not Casual, Contact. HIV and HBV are transmitted by: A. Sexual contact, shared drug needles, being stuck by an infected needle or other sharp instrument, or direct contact between broken or chafed skin and infected body fluids. B. HBV is also spread by contact with caked, dried blood and contaminated surfaces. HIV and HBV are not spread by: Coughing or sneezing, touching an infected person, or sharing equipment, materials, toilets, water fountains.

97. Universal Precautions Include Using PPE to Prevent Possibly Infectious Contact Wear gloves if there’s a risk of direct contact with body fluids or with possibly contaminated items or surfaces. Bandage cuts or broken skin before putting on gloves. Wear eye and face protection if there’s a risk of blood splashes or sprays. Wear protective clothing if there’s a risk of contact with body fluids. Use only PPE that’s been inspected for damage before wearing. Remove contaminated PPE carefully so contamination doesn’t touch your skin. Dispose of contaminated PPE in proper containers so contamination can’t spread.

98. BARRIER’S TECHNIQUE “SPECIALIZED CLOTHING OR EQUIPEMENT WORN BY EMPLOYEE FOR PROTECTION AGAINST INFECTION CONTROL (OSHA)”

99. PERSONAL PROTECTION CONTROL(PPE) HIRARCHY OF SAFETY AND HEALTH CONTROL

100. FACTORS INFLUENCING PPE SELECTION

101. Universal Precautions Include Good Hygiene Wash hands and exposed skin carefully with soap and water after exposure. Flush eyes, nose or mouth with water as soon as possible after contact with blood or potentially infectious materials. Don’t eat, drink, smoke, apply cosmetics, or handle contact lenses in areas that could contain infectious materials.

102. Universal Precautions Include Avoiding Direct Contact With Sharps OSHA says to treat all sharps as though they’re contaminated. Don’t shear or break or bend needles. Don’t reach your hand into a container that might contain sharps. Use tongs or a similar tool, not your hands, to clean up broken glass. Place all used sharps immediately in puncture-resistant, leak proof containers.

103. Universal Precautions Include Avoiding Direct Contact With Sharps Apply Universal Precautions to Possibly Contaminated Materials and Surfaces: Prompt and proper cleaning and decontamination for equipment or surfaces that have had contact with blood or potentially infectious materials Wearing gloves and using leak proof transport containers to handle laundry that may have had contact with blood or other potentially infectious fluids

104. What to do after needle stick injury: CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008

105. Sterilization Protocols for tuberculosis After Treatment of tuberculosis patients dental setting can be sterilized by: LpH ag ® manufactured by Steris Follow label directions of the disinfectant. On e part of disinfectant to 250 parts of water was mixed. Sodium hypochlorite Household bleach concentration is generally 5-6%. For Tuberculosis, it is recommended a dilution of 1 part of bleach and 4 parts of water (1/5 solution). PREvail TM  (accelerated hydrogen peroxide) manufactured by Virox Follow label directions of the disinfectant. Consideration of using 1/16 dilution and 10-20 minutes contact time in cold weather. CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008

106. Sterilization Protocols for tuberculosis Protocols to be followed by the Dental Professional : Proper masking Proper disinfection of the instrument . Avoid aerosol infection as much as possible. Proper personal protective equipment.

107. CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008

108. CLINICAL MANAGEMENT DURING AND AFTER COVID 19 PANDEMIC Before Dental Procedure Ensure safety by getting vaccinated OFFICE SET UP – Remove all the clutter and things from the practice that cannot be disinfected easily Schedule appointments with at least 30 mins between patients to minimize possible contact with other patients in the waiting room and disinfect the entire working area Request patients to come alone History of travel or any exposure or symptoms related to COVID-19 must be discussed on phone or text before the patients comes into the clinic Appointments to be scheduled and spaced to avoid crowding the waiting area CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008

109. During The Dental Procedure Hand Hygiene to minimize the risk of contamination. Indications for hand hygiene include : when hands are visibly soiled after barehanded touching of inanimate objects likely to be contaminated by blood, saliva, or respiratory secretions before and after treating each patient before donning gloves immediately after removing gloves Prefer extraoral radiological techniques Minimize aerosol production and its distribution in the air Prefer manual instrumentation CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008

110. During The Dental Procedure Hand Hygiene to minimize the risk of contamination. Indications for hand hygiene include : when hands are visibly soiled after barehanded touching of inanimate objects likely to be contaminated by blood, saliva, or respiratory secretions before and after treating each patient before donning gloves immediately after removing gloves Prefer extraoral radiologic techniques Minimize aerosol production and its distribution in the air Prefer manual instrumentation CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008

111. CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008

112. The Patient Treatment Area Areas and items of equipment local to the dental chair that need to be cleansed between each patient with 1% sodium hypochloride or 70% alcohol Disposable single-use covers are available for many of the devices like inspection light handles and headrests. For blood spillages, care should be taken to observe a protocol that ensures protection against infection. The use of hypochlorite at 1000 ppm available chlorine is recommended. Keep the Air conditioning vent facing upwards, use of air purifiers with HEPA filters. If the dental chairs are not six feet apart, then 2 patients should not be treated at the same time. CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008

113. The Patient Treatment Area Areas and items of equipment local to the dental chair that need to be cleansed between each patient with 1% sodium hypochloride or 70% alcohol Disposable single-use covers are available for many of the devices like inspection light handles and headrests. For blood spillages , care should be taken to observe a protocol that ensures protection against infection. The use of hypochlorite at 1000 ppm available chlorine is recommended . Keep the Air conditioning vent facing upwards, use of air purifiers with HEPA filters. If the dental chairs are not six feet apart, then 2 patients should not be treated at the same time. CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008

114. Personal protective equipment (PPE) Masks, Protective Eyewear, and Face Shields Wear a surgical mask and eye protection with a face shield to protect mucous membranes of the eyes, nose, and mouth during procedures Change masks between patients or during patient treatment if the mask becomes wet Protective Clothing Wear protective clothing (e.g., reusable or disposable gown) that covers personal clothing and skin Gloves Wear a new pair of medical gloves for each patient, remove them promptly after use CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008

115. Personal protective equipment (PPE) Masks, Protective Eyewear, and Face Shields Wear a surgical mask and eye protection with a face shield to protect mucous membranes of the eyes, nose, and mouth during procedures Change masks between patients or during patient treatment if the mask becomes wet Protective Clothing Wear protective clothing (e.g., reusable or disposable gown) that covers personal clothing and skin Gloves Wear a new pair of medical gloves for each patient, remove them promptly after use CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008

116. Technique for gloving: CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008

117. CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008

118. CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008

119. STERILIZATION PROTOCOL FOR HIV/HEPATITIS PATIENT Hepatitis B is one of the most common killer liver diseases. It is not only common man is affected but also medical personals. Following proper vaccination protocols as a prophylaxis along with proper sterilization and sanitation can prevent maximum proliferation of hepatitis B cases. There should be separate appointment for HIV/HEPATITIS patient. Any item that cannot be autoclaved should be disinfected with a fresh iodophor solution and protective cover should be placed. CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008

120. STERILIZATION PROTOCOL FOR HIV/HEPATITIS PATIENT Surfaces can be covered with plastic wrap , aluminum foil or impervious backed absorbent paper. Counter tops should be disinfected with appropriate disinfectants. Latex heavy rubber gloves also called utility gloves should be used in management of HIV patients. Instruments can be sterilized chemically. Chemicals used are ethyl alcohol, Sulfuric acid with potassium dichromate. These are disinfectants used in ultra sonic cleaner. Disposable instruments are preferred. CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008

121. Working field also causes contamination. So the work area is sterilized by 70 percent isopropylalcohol . Disposable tray sheets, suction tips, head rest cover, light handle cover, cover for switches and three way syringes must be used and changed for each patient. Impression sterilization is done by cleaning in running tap water and dipping it in glutaraldehyde or by spraying sodium hypochlorite and leaving for 10 minutes. OSHA. Universal precautions: safety training Guidelines

122. CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008

123. ROBOTS IN STERILIZATION   UV-D robots Robotics, is defined as the study of reprogrammable, multifaceted, versatile, and extensible systems that dynamically connect sensing to action . UV disinfection robots work on the principle of UVGI using ultraviolet (UV-C) light which has a wavelength of 254 nm and provides antimicrobial, antifungal and antiviral properties . Bhat VS, Shetty MS, Shenoy KK. Infection control in the prosthodontic laboratory. The Journal of Indian Prosthodontic Society. 2007 Apr 1;7(2):62.

124. Robots in Sterilization:  UV- D ROBOTS IN DISINFECTION UV-D Robots are powered by batteries and can kill up to 99.99% of germs. These gadgets are mobile base, have a number of Low-pressure Mercury (LPM) lamp, pulsed xenon lamps, and sensors for motion and are used to supplement hand cleaning This robot has various functions, including mapping the area, uses passive infrared sensors to sense its environment, camera with three-dimensional imaging to detect obstructions, choice of manual or automatic operation, and an exceptionally high degree of disinfection Bhat VS, Shetty MS, Shenoy KK. Infection control in the prosthodontic laboratory. The Journal of Indian Prosthodontic Society. 2007 Apr 1;7(2):62.

125. DIFFERENT UV ROBOTS Bhat VS, Shetty MS, Shenoy KK. Infection control in the prosthodontic laboratory. The Journal of Indian Prosthodontic Society. 2007 Apr 1;7(2):62.

126. Examples of different ultraviolet disinfection (UV-D) robots. ( A ) Xenex LightStrike -Germ-Zapping Robot. ( B ) Tru -D Smart UVC robot. ( C ) Helios UV-C Disinfection Robot- Surfacide . ( D ) VIOLET. ( E ) Artificial Intelligence Disinfection ROBOT (AIDBOT). C p baveja 5 th edition Examples of different ultraviolet disinfection (UV-D) robots.

127. ( A ) Xenex LightStrike -Germ-Zapping Robot. ( B ) Tru -D Smart UVC robot. ( C ) Helios UV-C Disinfection Robot- Surfacide . ( D ) VIOLET. ( E ) Artificial Intelligence Disinfection ROBOT (AIDBOT). Examples of different ultraviolet disinfection (UV-D) robots.

128. Conclusion Dentists must use effective infection control procedures in their practices. One should determine and practice infection control and build upon them by adding new procedures to the dental routine. Prevention of transmission of infectious diseases to patients and healthcare workers is a top priority, particularly during the pandemic. Healthcare workers should understand the criticality of the equipment and also the concepts of bioburden, sterilization, disinfection, cleaning, and Asepsis.AC

129. References Textbook of microbiology, C P Baveja, 5 th edition. http:// Connor C. Cross-contamination control in prosthodontic practice. International Journal of Prosthodontics. 1991 Jul 1;4(4). Httpp:// Bhat VS, Shetty MS, Shenoy KK. Infection control in the prosthodontic laboratory. The Journal of Indian Prosthodontic Society. 2007 Apr 1;7(2):62. CDC. Guidelines for Infection Control in Dental Health-Care Settings—2003 CDC. Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008 CDC. Summary of Infection Prevention Practices in Dental Settings: Basic Expectations for Safe Care Indian Dental Association PROTOCOL COVID-19 William A. Rutala and David J. Weber; Disinfection and Sterilization in Health Care Facilities OSHA. Universal precautions: safety training Guidelines Abichandani S, Nadiger R. Cross contamination in dentistry: A comprehensive overview. Journal of Education and Ethics in Dentistry. 2012 Jan 1;2(1):3.

130. http:// Indian Dental Association PROTOCOL COVID-19 http:// William A. Rutala and David J. Weber; Disinfection and Sterilization in Health Care Facilities OSHA. Universal precautions: safety training Guidelines http:// Abichandani S, Nadiger R. Cross contamination in dentistry: A comprehensive overview. Journal of Education and Ethics in Dentistry. 2012 Jan 1;2(1):3.