infection control in dental clinic

1. ‫الرحيم‬‫الرحمن‬‫هللا‬ ‫بسم‬
Mohanad Elsherif
BDS(U of K), MFD RCSI, MFDS RCPS(Glasg), MSc(Orthodontics),
M.Orth RCSEd

2. DEFINITIONs
• Infection: is invasion and multiplication of
microorganism inside the body.
• Infection control: refers to a
comprehensive and systematic program
that, when applied, prevents the
transmission of infective agents among
persons who are in direct or indirect
contact with health care environment.

3. CHAIN OF INFECTION

4. CHAIN OF INFECTION
Causative
agent
Reservoir Portal of
exit
Susceptible
host
Portal of
entry
Mode of
transmissio
n

5. # 1 Causative Agent
• Bacteria.
• Viruses.
• Fungi.
• Protozoa.
• Helminthes.

6. #2 Reservoir
• Humans ( patients and health workers).
• Animals.
• Insects.
• Environment:
•  Patient Care Equipment.
•  Environmental Surfaces.
•  Food.

7. # 3 Portal of Exit
• The path by which the infectious organism (agent)
leaves the reservoir e.g:
Coughing and
sneezing
Needle stick
injury

8. #4 Mode of Transmission
• The mechanism for transfer of an
infectious agent from the reservoir to a
susceptible host.
• Contact (Direct and Indirect).
• Airborne.
• Vector-Borne

9. #5 PORTAL OF ENTRY
• The path by which an infectious agent enters the
susceptible host.
• Respiratory Tract.
• Genitourinary Tract.
• Gastrointestinal Tract.
• Skin/Mucous Membrane.
• Trasplacental (fetus from mother).
• Parenteral (percutaneous, via blood).

10. #6 SUSCEPTIBLE HOST
• A person or animal lacking
effective resistance to a
particular pathogenic agent.

11. 3 words for infection control
P Prevention rotection recations

12. Immunization and Restrictions
Prevention

13. Immunization
• All dental personnel who provide patient care
or handle items contaminated with patient’s
blood or body fluids must be immunized
against Influenza, Tetanus/Diphtheria,
Measles/Mumps/Rubella, Polio, varicella and
TB.
• All DHCPs must also be immunized against
Hepatitis B virus.

14. Restrictions
• DHCP should refrain from providing patient care if
any of the following conditions are present:
• Gastro-intestinal Disturbance.
• Chicken Pox or Shingles.
• Fever or Flu.
• Conjunctivitis.
• The decision to restrict work or clinical activity must
be made in
consultation with the physician.

15. PROTECTION

16. Cross contamination cycle

17. 7 words to protect the community
What belongs to the clinic stays in
the clinic

18. Gloves
• Treatment gloves (examination and surgical):
• Always wear gloves when touching blood, saliva or mucous
membranes, and when examining all oral lesions.
• After each patient appointment, remove gloves and clean.
• Replace with a new pair of gloves before treating the next patient and
any time a tear or hole is apparent.
• Overgloves:
• Are to be worn over contaminated gloves when it is necessary to
handle equipment or supplies. Discard after each use.
• Utility gloves:
• When touching items or surfaces that may be contaminated with blood
and body fluids or secretions, utility gloves are to be worn.
• After each use, wash and dry reusable gloves or discard disposable
gloves.

20. Masks
• Surgical masks must be worn to protect oral and nasal
mucosa from spatter of blood and saliva.
• Contaminated masks should not be placed on forehead
or worn under the chin.
• Change the mask between patients or if it gets wet.
• Remove a used mask by the ties or elastic only.
• Masks must be worn by the person assisting, as well as
the person treating the patient.

21. Face Mask

22. Glasses
• Safety glasses with side shields or face shields
are to be used when splashing or spattering of
blood and saliva is likely.
• All protective eyewear must be washed with
soap and water and dried after each use.
• Protective eyewear must be worn by the
patient, the person treating the patient, and the
person assisting.

23. Glasses

24. Surgical cap
• Hair can trap heavy contamination that if
not washed away can be rubbed back
from pillow onto face at night. For that
the hair should be kept out of treatment
field by using surgical cap.

25. Surgical cap

26. Clinic Jackets / Lab Coats
• Long sleeve, cuffed clinic jackets are worn to
protect the user from injury and the spatter of
body fluids.
• Change daily or more often if visibly soiled.
• Clinic jackets and lab coats used for patient
treatment are not to be worn outside the
clinical area.

27. Precautions

28. 1.Hand washing
28

29. Hand washing
• Use cool water (hot water
opens skin pores) and
antiseptic soap.
• Time:
 2 min (beginning & end of
session).
 15 sec (between patients).

30. Hand washing
To do the job thoroughly you need to clean these 6 surfaces:
1) the palms.
2) the webs between the fingers.
3) the webs again with altered
Grip.
4) palms to knuckles of opposing
Hands.
5) thumbs clasped in opposing
Palm.
6) tips of fingers against palm of
opposing hand.

31. 2.DECONTAMINATIO
N

32. Decontamination
• Decontamination is the process by which microorganisms
are removed, inactivated or destroyed; in order to render
an object safe i.e. an object is no longer capable of
transmitting infectious particles when used, stored or
disposed.
• It includes:
 Cleaning.
 Disinfection.
 Sterilization.

33. Decontamination steps

34. cleaning
• Cleaning is the removal of all foreign material
(dirt, organic matter and microorganisms) from
an object.
• Two key components of cleaning are:
1. friction to remove foreign matter and fluids
and/or
2. rinse away contamination.

35. cleaning
• Cleaning is the first & the most essential
step in reprocessing of instruments and
equipment. If instruments and other
items have not been cleaned, sterilization
and disinfection may not be effective.
• Cleaning may be manual by hand or
mechanical by ultrasonic cleaners and
washers.

36. Ultrasonic cleaning unit

37. Cleaning washers

38. Disinfection
• Disinfection is a process that reduces the
number of pathogenic microorganisms,
but not necessarily bacterial spores, from
inanimate objects, to a level which is not
harmful to health.

39. The ideal disinfectant
 Resistant to inactivation.
 Broadly active (killing pathogens).
 Not poisonous (or otherwise harmful).
 Penetrating (to pathogens).
 Not damaging to non-living materials.
 Stable.
 Easy to work with.
 Otherwise not unpleasant.

40. Disinfection
• The broad category of disinfection may be subdivided,
according to the anti-microbial activity of the
disinfectant, into:
• High-level disinfectant (HLD): is capable of killing some
bacterial spores; when used in sufficient concentration
and temperature. It is effective against all vegetative
bacteria, fungi and all viruses.
• Examples:
• Boiling (100°C for 5 min).
• Moist heat at 70-100°C.
• chemicals like Glutaraldehyde 2% for 20 min or
Peracetic acid 0.2-0.35% for 5 min.

41. Disinfection
• Intermediate-level disinfectant (ILD):
• destroys all vegetative bacteria, including
Mycobacterium tuberculosis, lipid enveloped and some
non-lipid enveloped viruses, and fungus spores, but not
bacterial spores. e.g. same as HLD but with lower
concentration/tempreature and/or less time.
• Low-level disinfectant (LLD):
• destroys all vegetative bacteria (except Mycobacterium
tuberculosis), lipid viruses, some non-enveloped viruses
and some fungi, but not bacterial spores.
• E.g. same as HLD but with much less
concentration/tempreature and/or time.

42. sterilization
• Sterilization is a process which achieves
the complete destruction or killing of all
microorganisms, including bacterial
spores.

43. Method of sterilization
• Steam under pressure (Autoclaving)
• Dry heat (Hot Air Oven)
• The use of chemicals such as ethylene oxide
gas and Glutaraldehyde 2% .
• Others like radiation, freezing and filtration.

44. Pressure Steam Sterilization
(Autoclaving)
• Method:
• The steam must be applied for a
specified time so that the items reach a
specified temperature.
• It is done by:
121 °C for 15 min and 15Ibs pressure.
134 °C for 7 min and 30Ibs.

45. Pressures steam sterilizer (autoclave)

46. Advantages
of steam sterilization
• Highly effective.
• Rapid heating and rapid penetration of
instruments.
• Nontoxic.
• Inexpensive.
• Can be used to sterilize liquids.

47. Disadvantages
of steam sterilization
• Items must be heat and moisture
resistant.
• Will not sterilize powders, ointments or
oils.
• Needs good maintenance.

48. Dry-heat Sterilization
(Hot air oven)
• Dry heat is preferred for reusable glass,
metal instruments, oil, ointments and
powders.
• Do not use this method of sterilization for
other items, which may melt or burn.

49. Hot air oven

50. Method
Holding temperature Sterilization time (after reaching the
holding temperature)
180 ºC 30 minutes
170ºC 1 hour
160ºC 2 hours
149ºC 2.5 hours
141ºC 3 hours

51. advantages
• Can be used for powders, anhydrous oils,
and glass.
• Reaches surfaces of instruments that cannot
be disassembled.
• No corrosive or rusting effect on instruments.
• Low cost.

52. disadvantages
• Penetrates materials slowly and
unevenly.
• Long exposure time’s necessary.
• High temperatures damage rubber goods
and some fabrics.
• Limited package materials.

53. Ethylene oxide gas
• Used to sterilize most articles that can withstand
temperatures of 50-60°C.
• It should be used under carefully controlled conditions
because it is extremely toxic and explosive.
• A long period of aeration (to remove all traces of the gas)
is required before the equipment can be distributed.
• The operating cycle ranges from 2-24 hours.
• It is a relatively expensive process.
• Sterilization with ethylene oxide should be monitored by
using bacterial spore tests.

54. Ethylene oxide sterlizer

55. Spaulding classification
• A strategy developed by Dr: Earle H.Spaulding
for reprocessing of contaminated medical
devices.
• The system classifies devices as critical, semi-
critical, or non-critical items; based on the risk
of infection of patient from contaminated
devices.

56. High-risk “Critical” Items
• Classification: Critical objects enter normally sterile
tissue or vascular system, or through body cavities.
• Objective: Sterility.
• Level germicidal action: Kill all microorganisms,
including bacterial spores.
• Examples: Surgical instruments like scalpels and
scissors.
• Method: Steam, EO gas, hydrogen peroxide plasma or
chemical sterilization.

57. Intermediate-risk “Semi-critical”
Items
• Classification: Semicritical objects come in contact
with mucous membranes or skin that is not intact.
• Objective: Free of all microorganisms except some
bacterial spores.
• Level germicidal action: Kills all microorganisms except
some bacterial spores.
• Examples: dental mirrors and Impression trays.
• Method: High-level disinfection is enough but
sterilization is better.

58. Low-risk “Non-critical”
Items
• Classification: Noncritical objects come in contact with
normal intact skin, but not with mucous membranes.
• Objective: Kill all microorganisms except spores.
• Level germicidal action: Kill vegetative bacteria, fungi
and lipid viruses.
• Examples: blood pressure cuff, facebows and
inanimate environment (e.g. walls, floors, ceilings,
furniture, sinks, etc.).
• Method: Low-level disinfection

59. Monitoring the Effectiveness
of Sterilization
• Mechanical indicators:
• Measure time, temperature, pressure.
• Chemical indicators:
• Change in color when physical parameter is reached.
• Biological indicators:
• Use biological spores to assess the sterilization process
directly. E.g.
• Steam - Geobacillus stearothermophilus.
• Dry heat - B. atrophaeus (formerly B. subtilis).
• Ethylene Oxide - B. atrophaeus.

60. Chemical indicators Biological indicators

61. Recommended
ideal monitoring system
• For steam & dry heat sterilization:
• If the autoclave has recording chart, review it after
each load. If not, record the temperature, time and
pressure information in a log book that is reviewed
after each load.
• Place heat-and steam-sensitive chemical indicators, if
available, on the outside of each pack.
• Perform testing with biological indicators weekly.

62. Recording chart for sterilization

63. Recommended
ideal monitoring system
• Indicators should be in the middle of the item
reprocessed (the most difficult part of the load).
• A thermometer could be put in the most difficult part of
the load.
• For chemical sterilization:
• Record the time information in a log book that is
reviewed after each load.
• Use an indicator strip, if available, to determine if the
solution is still effective.

64. Storage of Sterile Items
• Sterile storage area should be well-ventilated area that
provides protection against dust, moisture, temperature
and humidity extremes.
• Sterile items should be stored so that packaging is not
compromised.
• Sterilized items should be labeled with a load number
that indicates the sterilizer used, the cycle or load
number, the date of sterilization and the expiration
date.

65. 3.Maintaining a Clean clinic

66. Maintaining a clean clinic
• Always clean and disinfect the dental unit
carefully, before treating the first patient of the
day and after each patient, to prevent cross-
contamination.
• Cleaning removes visible soil and disinfection
kills or destroys all disease-producing
microorganisms except spores.
• Protective attire (gloves, mask, and eyewear)
is to be worn while cleaning and disinfecting.

67. Water Lines
• Flush all water lines for at least 3 minutes at
the beginning of the day and for 30 seconds
after each patient.
• Wear protective attire (gloves, mask, eyewear).
• Discharge water into sink or evacuation
system.
• Use sterile water for surgical procedures.

68. Dental chair
• Wear protective attire (gloves, mask, eyewear).
• Apply disinfectant to Kimtowel and clean each item.
• Use a separate Kimtowel for each item.
• Re-apply and disinfect each item with another
Kimtowel.
• Allow 10 minutes to air dry.
• When dry, apply clean plastic barriers to headrest and
light handles.
• Dental light cover - do not use disinfectant - let cool and
wipe with Kimtowel moistened with detergent and
water.

69. Others
• Handpieces:
• Assemble sterilized handpiece and attachments.
• Ultrasonic Scalers:
• Attach sterilized scaler and tip.
• Sterile Instruments:
• Open sterile trays and instrument packages immediately prior to
use to decrease contamination of contents.
• Consumable Supplies:
• Bring only those items necessary for treatment into the operatory.
• Dental Equipment:
• Collect all necessary equipment and materials prior to beginning
treatment.

70. 4.Handling of sharp instruments and needles

71. Handling of sharp instruments and needles
• Used needles, scalpel blades and other sharp
instruments are considered potentially infective
and are to be handled carefully to prevent
unintentional injuries.
• To remove a sharp object, use a hemostat or
instrument, not your hands.

72. Needle
• DO NOT recap used needles by hand.
• DO NOT remove used needles from the
dental syringe by hand.
• DO NOT bend, break or otherwise
manipulate used needles by hand.

73. scalpel
• Remove used blade from handle using
blade remover or hemostat.

74. 5.Disposal of waste Materials

75. Disposal of Waste Materials
• Providing dental care creates wastes, which
must be handled safely and in accord with local
and provincial regulations.
• Sharps:
• Disposable needles, scalpel blades and other
sharp items must be placed intact into
puncture - resistant containers before disposal.

76. Sharps container with biohazard label warning

77. Disposal of Waste Materials
• Fluids:
• Blood, suctioned fluids or other liquid waste
may be carefully poured into a drain connected
to a sanitary sewer system. If infectious
organisms are known or suspected to be
present like HBV, disinfect fluid waste with
bleach prior to discarding.

78. Disposal of Waste Materials
• Solids:
• Solid waste, i.e., gloves, masks, suction tips
contaminated with blood or body fluids are to be
placed in sealed, sturdy, impervious bags to minimize
human contact. Items that are dripping blood, or
saturated with it, may be reduced to general waste by
simply squeezing or rinsing out over a sink. If infectious
organisms are known or suspected to be present, solid
wastes must be autoclaved prior to disposal.

79. Patient with HIV

80. Additional precautions to be taken when performing
invasive procedures on HIV
infected individuals
1. If possible, schedule the patient surgery at the end of
the list.
2. The team should be limited to essential members of
staff and the procedures should be performed by
experienced, fully trained staff.
3. The operator should wear two pairs of gloves. Plastic
gown, cap, mask and protective eye wear should be
worn.

81. Cont HIV patients
4. All procedures should be performed in a way which
minimizes the formation of droplets, spatter and aerosols,
utilizing high volume vacuum aspirators, rubber dams
where appropriate and proper patient positioning.
Ultrasonic scalers should be avoided.
5. Avoid the use of instruments which cannot be easily
decontaminated. Instruments and tools used should be
handled and cleansed by experienced staff before
autoclaving.
6. After the operation, all surfaces inside the surgery and
equipment should be cleaned and decontaminated with
appropriate disinfectants.

82. Management of needle stick injury

83. Management of needle stick injury
• Report the incident immediately.
• Wash the area immediately under running water.
• Make the wound bleed for three to four minutes whilst continuing
to wash the area.
• Dry area with paper towel.
• Cover the wound with a water-impermeable sticking plaster and
consider double gloving any hand injury, if continuing to work.
• Seek appropriate medical advice.
• The source patient should be identified and arrangements made
for a blood sample to be obtained, with informed consent. This
should be tested for the presence of the blood borne viruses
hepatitis B, hepatitis C and HIV.

84. Management of needle stick injury
• Arrangements should be made for blood samples to be taken
from the staff member (victim) with informed consent. One
sample is marked “for storage” and is retained in the relevant
laboratory. The other is analyzed to determine the staff member’s
hepatitis B antibody level.
• Further assessment, treatment and follow up of the staff member
are performed in accordance with current best practice.
• Arrangements should be in place for speedy assessment and
treatment.
• Counseling, reassurance and information may be required and
arrangements for accessing this should be in place as appropriate.
• Appropriate records must be kept.

85. Treat every
patient as if
he/she is
infected.
And finally
Remember

87. Declaration
 The author wish to declare that; these presentations are his
original work, all materials and pictures collection, typing and
slide design has been done by the author.
 Most of these materials has been done for undergraduate
students, although postgraduate students may find some useful
basic and advanced information.
 As the authors reviews several textbooks, papers and other
references during preparation of these material, it was
impossible to cite every textbook, journal article, and clinical
guidelines.
 The author declare that all materials and photos in these
presentations has been collected from different textbooks,
papers and online websites. These pictures are presented here
for education and demonstration purposes only. The author are
not attempting to plagiarize or reproduced unauthorized
material, and the intellectual properties of these photos belong
to their original authors.

88. Declaration
 For the purposes of dissemination and sharing of
knowledge, these lectures were given to several
colleagues and students. It were also uploaded to
SlideShare website by the author. Colleagues and
students may download, use, and modify these
materials as they see fit for non-profit purposes. The
author retain the copyright of the original work.
 The author wish to thank his family, teachers,
colleagues and students for their love and support
throughout his career. I also wish to express my
sincere gratitude to all orthodontic pillars for their
tremendous contribution to our specialty.
 Finally, the author welcome any advices and enquires
through his email address: Mohanad-07@hotmail.com

89. ‫هللا‬ ‫بحمد‬ ‫تم‬