1. Infection control in ConservativeDentistry & Endodontics withemphasis on Biomedical wastemanagementPraveen Jangid

2. Definitions: Sterilization: Process by which an articles, surface or medium is freed ofall microorganism either in vegetative or spore form. Disinfection : Process which reduces the number of viable microorganismto an acceptable level but may not inactivate some virus and bacterialspores. Antiseptic : Chemical which can be safely applied to skin or mucusmembrane surfaces and used for preventing infection by inhibiting growthof bacteria. Cross infection control :Is the sum total of all the measures taken toprevent subsequent infection. 3. Why is Infection Control Important in Dentistry? Both patients and dental health care personnel (DHCP) can be exposed topathogens Contact with blood, oral and respiratory secretions, and contaminatedequipment occurs Proper procedures can prevent transmission of infections among patientsand DHCP Direct contact with blood or body fluids Indirect contact with a contaminated instrument or surface Contact of mucosa of the eyes, nose, or mouth with droplets or spatter Inhalation of airborne microorganismsDCNA 2003;691-708Modes of Transmission 4. Chain of infection All links must be connected for infection to take placePathogenSourceSusceptible HostEntry Mode 5. Factors or determinants of an infectious disease The interaction determines the outcome of an infection as followsHealth or Disease = Virulence X DoseBody Resistance Health is favoured by decrease in virulence & dose of microrganisms. Disease is favored by increase in virulence & dose of micro. & decrease inresistance.Approach to infection control Reducing dose of microorganisms that might be shared between patients &dental team. Increasing resistance of dental team by immunization against specificinfections. 6. Exposure risks in dental operatoryA) Airborne contaminationB) Hand-to-surface contaminationC) Cross infectionD) Patient vulnerabilityE) Personnel vulnerabilityA) Airborne contamination A high speed handpiece is capable of creating airborne contaminants. It exist in the form of aerosols, mists, and spatter 7. Aerosols are invisible particles ranging from 5- 50 microns. Remain suspended in air for hours Can carry any respiratory pathogens to the lungs.J Dent Rest 48;49-56,1969 Study used water-soluble red-fluorescent poster paint (plain water-solublefluorescent-red tempera in water) as a visible substitute for saliva to elevateawareness and facilitate problem solving in infection controlJ Am Dent Assoc 96:801804, 1978 8. Mists are droplets approaching 50microns or more Tend to settle gradually from air after 5-15 min Both aerosols and mists produced by cough of patient with unrecognizedactive pulmonary or Pharyngeal tuberculosis are likely to transmit theinfection.Spatter are particles larger than 50 microns and are visible. They have a distinct trajectory, usually falling within 3 feet of patientmouth. Spatter has a potential of causing infection of dental personnel by bloodborne pathogens.J Am Dent Assoc 125;579-84;1994Morbid Mortal Wkly Rep 38;5-6,1989 9. B) Hand-to-surface-contamination With saliva contaminated hands, the dentist could repeatedly contact orhandle unprotected Operatory surfaces during treatment if not careful. Amalgamator, light curing devices, camera equipments are also subject toheavy contamination by soiled hands. Mobile phones may also act as an important source of nosocomialpathogens in the dental settingJ Dent Educ .2010 Oct;74(10):1153-8 Contamination free maintenance of these items is a priority objective today. 10. C) Cross infection The transmission of infectious agents between patients and staff within aclinical environment Transmission may result from person to person contact or via contaminatedobjects. Patient-to-patient transmission of hepatitis B virus (HBV) - transmissionof a blood borne pathogen in a dental setting in the United States.The Journal of Infectious Diseases 2007; 195:13114 The major route of cross infection in Conservative Dentistry andEndodontics is via infection through intact skin or mucosa due to accidentsinvolving sharps, or direct inoculation onto cuts and abrasions in the skin. 11. D) Patient vulnerability Although infection risks for dental patients have not been as wellinvestigated as those of hospital patients, they appear to be low. Nine cluster cases of dentist-to-patient transmission of HB and one clustercase of HIV has been well documented since 1971. In 1999, a group of six patients was found to be with same strain of HIVvirus that infected the Florida dentist who treated them.E) Personnel vulnerabilitySurveillance Report 10;26;1998 When dental personnel experience exposure of saliva, blood, and possibleinjury from sharp instrumentation while treating patients, they are morevulnerable to infections if they have not had proper immunizations or usedthe protective barriers.J Am dent assoc 110;629-33;1985 12. Infection control program To reflect new data, materials, technology, and equipment.When implemented. Types of infection control program 1. IC program by center for disease control and prevention 2. IC program by ADA (American Dental Association) 3. IC program by Federal Occupational Safety and HealthAgency (OSHA) 13. Exposure Control Plan by OSHA Use of Universal Precautions Required use of personal protective equipment Standardized housekeeping Laundering of contaminated protective clothing Policy on general waste disposal Labeling procedure Policy on sterilization (including monitoring) and disinfection Standardized handwashing protocol Hepatitis B virus (HBV) vaccination Postexposure evaluation and medical follow-up 14. Standard Precautions Wash hands before and after every patient. Wear gloves when touching blood, body fluids, secretions, andcontaminated items. Use care when handling sharps. Wear a mask and eye protection, or a face shield. Carefully handle contaminated patient care items to prevent the transfer ofmicroorganisms to people or equipment. Use a mouthpiece or another ventilation device as an alternative to mouth-to-mouth resuscitation when practical. Standard Precautions must be used in the treatment of all patients. 15. Hand Hygiene Wash hands before putting on gloves andimmediately after removal At beginning of treatment period - jewelry,and rings should be removed long fingernails can harbour pathogens,nails should be kept short. Treatment room sinks be equipped withhands-free faucets that are activatedelectronically or with foot pedals 16. use liquid soap as bar soap may transmit contamination Waterless antiseptic agents are alcohol based products that are available in gels,foams, or rinses. Hand cleansers containing a mild antiseptic like 3% PCMX (parachlorometa-xylenole)or chlorhexidine - preferred to control transient pathogens and tosuppress overgrowth of skin bacteriaInfect Control Hosp Epidemiol 12;654-62;1991 4% chlorhexidine broader activity but hazardous to eyesJ Am Dent Assoc 99;65-7;1979Am J Ophthalmol 104;50-56;1987 17. Personal Protective Equipment Protective clothing Protective eyewear Surgical mask Gloves 18. Protective Clothing Requirements should be made of fluid-resistant material. To minimize the amount of uncovered skin, clothing should have longsleeves and a high neckline. Buttons, trim, zippers, and other ornamentation (may harbour pathogens)should be kept to a minimum.Guidelines for the Use of Protective Clothing not worn out of the office for any reason Protective clothing should be changed at least daily and more often ifvisibly soiled. If a protective garment becomes visibly soiled or saturated with chemicalsor body fluids, it should be changed immediately. Hot water (70 -158 F) or Cool water containing 50 to 150 ppm ofchlorine can be used- to provide more antimicrobial actionGarner JS, Favoero MS ; 1985; Center for Disease control 19. Protective Masks Worn over the nose and mouth to protect from inhaling infectiousorganisms A mask with at least 95 percent filtration efficiency for particles 3 to 5micrometers (m) in diameter should be worn whenever splash or spatter islikely Recommendations for changing mask after 20 min in aerosol & 60 minin non-aerosol environment When not in use, it should never be worn below the nose or on the chin. Two most common types of masks are the domeshaped and flat types 20. Average surgical mask does not protect one from the influx of very smallvirus particles in the air National Institute for Occupational Safety and Health (NIOSH) and theCenters for Disease Control and Prevention (CDC) recommend the use of aNIOSH-certified N95 for the protection of healthcare workers who come indirect contact with patients with H1N1 21. Protective Eyewear Worn to protect the eyes against damagefrom aerosolized pathogens Eyewear must be optically clear, anti-fog,distortion-free, close-fitting andshould be shielded at the sides BBP Standard requires the use ofeyewear with both front and sideprotection during exposure proneprocedures 22. Face Shields Chin-length plastic face shield may beworn as an alternative to protectiveeyewear. Shield cannot replace face maskbecause it does not protect againstinhalation of contaminated aerosols 23. Gloves Medical grade nonsterile examination gloves and sterile surgical gloves aremedical devices that are regulated by the U.S. Food and DrugAdministration (FDA). Different types of gloves are used in a dental officeExaminationGloves/ surgicalglovesOvergloves Utility GlovesNonLatex-Containing Gloves 24. Guidelines for the Use of Gloves Single use. May not be washed, disinfected, or sterilized. Gloves DO NOT replace the need for hand hygiene. Wash hands before donning gloves and upon glove removal Open new fresh gloves just before starting procedure Replace torn or damaged gloves immediately. Do not wear jewellery under gloves Remove contaminated gloves before leaving the chair side during patientcare, and replace them with new gloves before returning to patient care 25. How to wear glovesHow to remove gloves 26. Maintaining Infection control while gloved Anticipate required materials and have those items ready and easilyaccessible for each procedure to save time and minimize cross-contamination When opening a container use overgloves, a paper towel, or a sterile gauzesponge . In doing this, take care not to touch any surface of the container. Use sterile cotton pliers to remove an item from the container 27. Managing Contaminated Sharps Contaminated needles and other disposable sharps must be placed into asharps container. The sharps container must be puncture-resistant, closable, leakproof, andcolor-coded Sharps containers must be located as close as possible Always use the single-handed scoop technique or some type of safetydevice 28. Hospital waste categories and disposalPark 20th/698 29. Mercury Spill Kits MERCURY MAGNETTM powder is the remedy for proper decontamination andclean up of a mercury spill area. Concentrations of mercury vapor greater than 0.1mg/m3 exceed the OSHApermissible exposure limit. Concentrations of up to 20mg/m3 can go unnoticedfor long periods of time, creating a serious hazard to health. The powder reacts with liquid mercury to form a solidified amalgam, which notonly brings the mercury vapor pressure below harmful levels, but also allows easypick up using a common magnet 30. Selenium acts as a mercury magnet with a very strong binding affinity forthe toxic substance. This strong attraction allows selenium to mix and neutralize their reactioncharacteristics. This new Hg - Se substance that is produced is not absorbed by the bodyand gets flushed out of the system. This is a very beneficial interaction that removes mercury from the bodybefore it can lodge in fatty tissue and cause damage.http://www.naturalnews.com/030130_selenium_mercury.html#ixzz36ymWqwe7 31. Operatory Asepsis Design of the premises and the layout of the dental surgery and treatmentareas are important factors in implementing successful infection control Dental operatory and the instrument reprocessing rooms must have clearlydefined clean and contaminated zones Floor coverings in the dental operatory must be non-slip and imperviouswith sealed joints Computer keyboards should be covered where possible in treatment areas,and cleaned regularly in non-treatment areas. A number of keyboards are available that have flat surfaces and can bewiped over with detergent or with alcohol-impregnated wipes betweenpatient appointments. 32. Materials impervious to moisture that are used to prevent contamination ofsurfaces. Plastic sheets Impervious paper Aluminum foilsUsed in areas difficult to clean and disinfect- Air water syringe- Dental light handles- Electrical toggle switches- Head rest- X Ray unit heads 33. Waterlines and water quality Microbes exist in the dental unit water line asbiofilm. bacteria may include atypical mycobacteria,pseudomonas, and Legionella CDC has recommended that dental unittreatment water contain less than 500 colony-formingunits (cfu) per milliliter of bacteria. Disinfectants such as an iodophore or dilutedsodium hypochlorite that are used to clean thesystem 34. All waterlines must be fitted with non-return (anti-retraction) valves to helpprevent retrograde contamination of the lines by fluids from the oral cavity. Air and waterlines from any device connected to the dental water systemthat enters the patients mouth (e.g. handpieces, ultrasonic scalers, andair/water syringes) should be flushed for a minimum of two minutes at thestart of the day and for 30 seconds between patients 35. High risk infections & protocol to be followed fortreating high risk infectious patients Dental patients and Dental Health Care Workers (DHCWs) may be exposed to avariety of microorganisms via blood or oral or respiratory secretions. These microorganisms may include human immunodeficiency virus (HIV),hepatitis B virus (HBV), hepatitis C virus (HCV), herpes simplex virus types 1 and2, Mycobacterium tuberculosis Recently exposure to DHCWs and patients by Prions has come to limelight Prions are proteins that have been linked to fatal neurodegenerative disordercommonly called as transmissible spongiform encephalopathiesJ Endod 2007;33 442-446 36. Protocol to be followed :- High risk patients should be seen last Protective attire and barrier techniques Vaccines for dental health-care workers Use and care of sharp instruments and needles Cleaning and disinfection of dental unit and environmental surfaces Use single-use disposable items and equipment Consider items difficult to clean (e.g., endodontic files, broaches) as single-usedisposable Keep instruments moist until cleaned Clean and autoclave at 134C for 18 minutes 37. Immunisation Dental personnel should maintain up-to-date immunization records thatinclude vaccination against: A) HEPATITIS B B) RUBELLA C) MEASLES D) MUMPS E) INFLUENZA F) POLIO G) TETANUS/DIPHTHERIAMMR 38. Recommended Vaccines for Oral Health Care workersHepatitis B(Recombinant )Two doses IM 4 weeks apart, third dose 5months after secondMMR(Live Virus Vaccine)One dose SC ..No boosterInfluenza Vaccine(inactivated whole virus and split virusvaccine)Annual VaccinationTetanus Diphtheria(Toxoid)Two doses IM 4 weeks apart, third dose 6 12 months after second.Booster dose every 10 yearsVaricella(Live virus vaccine)One dose SC for persons ages 12 monthsto 12 years, Second dose 4 8 weeks afterfirst for those ages 13 and up 39. For HIV virusAfter immediate exposure- Decontamination of wound Base line laboratory test for health care workers Selection of PEP regimen PEP regimen includes two NRTI typically zidovudine andlamivudine Expanded regimen includes basic regimen plus nelfinavir andefavirenz After this HIV screening at 6 weeks, 3 months, and 6 months 40. For HB Hepatitis B vaccine series should be initiated in non-HBV-immune healthcare professionals Administration of prophylactic Hepatitis B immune globulin and initiationof hepatitis B vaccines series should be done at different sites. Following an exposure HB and HC serology should be determined If a source patients is known to be HCV antibody positive baseline thenHCV serology and serum ALT should be obtained from exposed healthcare professionals and after 4 weeks HCV viral load (HCV RNA PCR)should be done HBV infections responds to 70-90% when HBIG is administered within 7days. 41. Mycobacterium tuberculosis All dental healthcare professionals (DHCPs) should be educated regardingthe signs, symptoms, and transmission of tuberculosis All DHCPs who could have contact with persons with suspected orconfirmed cases of TB should have a baseline tuberculosis skin test Assess each patient for a history of TB, and document it on the medicalhistory.The following applies to patients known or suspected to have active TB: The patient should be evaluated away from other patients and personnel. Elective dental treatment should be deferred until the patient is non-infectious. Patients who require urgent dental treatment should be referred to a facilitywith TB engineering controls and a respiratory protection program. 42. Creutzfeldt-Jakob Disease and OtherPrion Diseases Creutzfeldt-Jakob disease (CJD) belongs to a group of rapidly progressive,invariably fatal, degenerative neurologic disorders. Prion diseases have an incubation period (time between infection and signsof disease) of years and are usually fatal within one year of diagnosis. Theoretical risk of transmission of prion disease through dental treatmentemphasizes the need to maintain optimal standards of infection control anddecontamination procedures for all infectious agents including prionsJ Can Dent Assoc 2006; 72(1):5360 43. Applying First Aid after an Exposure IncidentProcedural Steps Stop operations immediately. Remove your gloves. If the area of broken skin is bleeding, gently squeeze the site toexpress a small amount of visible blood. Wash your hands thoroughly, using antimicrobial soap and warmwater. Dry your hands. Apply a small amount of antiseptic to the affected area.Do not apply caustic agents such as bleach or disinfectantsolutions to the wound. Apply an adhesive bandage to the area. 44. Office design Office design split into 3 distinct areas: a) Operator area b) Dental assistant area c) Sterilization and storage areaInf. Cont. & manag. Haza. Mat. For dent.team,2013;pn145. 45. Instrument processing Contaminated instruments can transmit infections between patients,correct reprocessing of instruments between each patient use isessentialSteps Involved Presoaking Cleaning Packaging Sterilization Drying or cooling 46. Categories of instrumentsSpauldings Classification 47. Presoaking Most disinfectants do not act in the presence of debris, so they should beremoved. It is easier to remove the debris before it dries. Placing the instrument in a presoak solution until time is available for fullcleaning prevents drying and begins to dissolve or soften the debris. Presoak solutions used are detergents, enzymes, phenols, quaternaryammonium compounds. 48. All items to be sterilized must be properly cleaned first to reduces bio-burdenUltrasonic cleaners These are safest and most efficient ways to clean instruments Ultrasonic cleaning is 9 times more effective than hand cleaning An ultrasonic cleaning device provides fast and thorough cleaning withoutdamage to instrumentsSociety for Infection Control in Dentistry 6:2, 1991Cleaning 49. Instrument Containment Cloth packs, wraps, or plastic bags are suitable for instrumentcontainment if they are compatible with the method and temperature ofsterilization. Various kinds of instrument trays and cassettes are manufactured tocontain the instruments at chairside, and they can be placed in anultrasonic cleaner, rinsed, and packaged ready for sterilization. 50. Selection of Packaging materialsMethod of sterilization Packaging materialsSteamPaper / Plastic pouches /Wrapped cassettes / Thin clothChemical vapourPaper wrap / Paper peelpouchesDry heatNylon plastic tubing /Sterilization paper wrap / Foil 51. STERILIZATION Most instruments contact mucosa or penetrate oral tissues, it isessential that reused instruments be thoroughly cleaned andsterilized by accepted method that can be routinely tested andmonitored.J Am Dent Assoc 123(Suppl):18, 19924 accepted method of sterilization -1. Steam pressure sterilization (Autoclave)2. Chemical vapor pressure sterilization (Chemiclave)3. Dry heat sterilization (Dryclave)4. Ethylene oxide sterilization(ETOX) 52. Autoclave Sterilization with steam under pressure is performed in a steam autoclave Time required at 1210 C is 15 mins at 15 lbs of pressure or 134o C at 30 lbs pressurefor 7 minAdvantages most rapid and effective for sterilizing cloth surgical packs and towel packsDisadvantages of Autoclave Items sensitive to heat cannot be sterilized It tends to corrode carbon steel burs and instruments 53. Sterilization Of Burs In Autoclaves Burs can be protected by keeping them submerged in a small amount of 2% sodiumnitrite solution. Prepare fresh sodium nitrite solution by adding 20gms of crystal to 1 liter of waterand place it in a perforated beaker containing burs. The solution should be above the burs by approximately 1cmJ Am Dent Assoc 110:629633, 1985 54. Chemiclave Chemiclaves utilize chemical vapor for sterilization produced using formaldehyde-and-alcohol formulation that is water-free operates at 131 C and 20 pounds of pressure for 30 minAdvantages Carbon steel and other carbon sensitive burs, instruments and pliers are sterilizedwithout corrosionDisadvantages Items sensitive to elevated temperature will be damaged Towel and heavy clothing cannot be sterilized. 55. Dry Heat SterilizationConventional dry heat ovens: Most common time temperature cycles are 170C (340F) for 60 minutes, 160C(320F) for 120 minutes, and 150C (300F) for 150 minutes. Recently, more rapid dry heat sterilizers (COX sterilizers) have become available;these can be operated at 370F for 6-, 8- or 12-minute cyclesAdvantages Carbon steel instruments and burs do not rust, corrode, or lose their temper orcutting edges if they are well dried before processing.Disadvantages High temperatures may damage more heat-sensitive items such as rubber or plasticgoods. Sterilization cycles are prolonged at lower temperatures. 56. Ethylene oxide sterilization Best method of sterilization of complex instruments and delicate materials. Automatic devices sterilize items in several hours and operate at elevatedtemperature well below 1000 C Less expensive device operates at room temperature to sterilize overnightAdvantages Units with large chambers hold more instruments or packs per cycleDisadvantages Porous or plastic materials absorb the gas and require aeration for 24 hours or morebefore it is safe for them to contact skin or tissues. 57. Boiling Water Boiling water does not kill spores and cannot sterilize instruments Incase of sterilizer breakdown - this method should be followed Well cleaned items must be completely submerged and allowed to boil at 1000 C for10 minsDisinfection, sterilization, and preservation, ed4, Philadelphia, 1991, Lea & Febiger 58. Endodontic instruments sterilization Proper steam autoclaving reliably produced completely sterileinstruments. Salt sterilization and glutaraldehyde solutions may not be adequatesterilization methods for endodontic hand files and should not berelied on to provide completely sterile instrumentsJournal of Endodontics; 1996;22; 6; 321-322. Files sterilized by autoclave and lasers were completely sterile.Those sterilized by glass bead were 90% sterile and those withglutaraldehyde were 80% sterile.J Indian Soc Pedod Prevent Dent ;28;1;2010 59. Individual instruments can be sterilized in the following ways - Glass slab by swabbing with tincture of thimerosal, followed by adouble swabbing with alcohol. Gutta-percha cones may be kept in sterile screw capped vialscontaining alcohol. To sterilize gutta-percha cone freshly removed from the box-immersein 5.2% sodium hypochlorite for 1 min, then rinse withhydrogen peroxide and dry between 2 layers of sterile gauze. 60. Silver cones are sterilized by passing them through a flame 3-4 times or byimmersion in hot salt sterilizer for 5 secs. Rubber dam is sterilized by ethylene oxide. Carbon steel instruments and burs are best sterilized by dry heat orchemiclave. Sterilization dental cements, calcium sulphate is done by gamma radiation 61. Disinfection of impression Before disinfection, dental impressions must be rinsed to remove debris,saliva and blood. Disinfection of impressions is done by immersion incompatible disinfecting agent for 15 to 30 minutes depending onmanufacturers recommendation for proper disinfection.Type of Impression Material and Recommended Disinfectants1. Alginate Immerse in iodophors or 0.5% hypochlorite2. Polysulfide Immerse in glutaraldehyde, iodophor, 0.5% hypochloriteor phenolic3. Silicone Immersion in any disinfectant4. Polyether Spray and wrap in iodophor, 0.5% hypochlorite, phenolicdisinfectants.5. Hydrocolloid Immerse in iodophor, 0.5% hypochlorite6. Impression Compound Immerse in iodophor, 0.5% hypochlorite 62. Sterilization Monitoring Biological indicators : Bacillus stereothermophilus ( steam or chemiclave ) Bacillus subtilus (dry heat ) Chemical indicators Color change strips or tapes Physical indicators Routine observations of dials / gauges indicating time ,temperature & pressure 63. Conclusion Infection control measures in dentistry are most vital formutual health safety of patient and health care professionals. There are several key players and elements to achieve thehighest standard of infection control. These include the Dentalhealth care professionals and the patients. Rigid implementation of evidences based infection controlmeasures should be strictly followed in dental practice.Whatever is touched is contaminated 64. Thank you.