Infection Control and Patient Safety

- Definitions.
The following definitions are provided by the ICPS (International Patient Safety Classification)
proposed by the World Alliance for Patient Safety of the World Health Organization (WHO).

1. Patient Safety.
Patient safety means a decrease in (or elimination of, to the greatest extent possible) the harm to
patients caused by treatments provided, or from accidents associated with those treatments.

2. Risk Management.
This is the attempt to identify, evaluate and deal with problems which may cause harm to patients,
to file complaints about malpractice and to avoid unnecessary economic losses for health care
providers.

3. Adverse Event.
 Unexpected result of a health care treatment which leads to prolonging treatment, some type
of morbidity, mortality
 Or simply any harm which the patient should not have suffered.
 Broad concept which includes errors, accidents, delays in providing care, negligence, etc., but
not the complications inherent to the patient’s disorder or disease itself.
4. Error.
 Mistake due to action or mission in health care practice, whether an error of planning or an
error of execution.
 The error may or may not lead to the existence of an adverse event.
5. Near miss.
 Event which nearly causes harm to the patient and which is avoided by luck or due to action
at the last moment.
 Example: prescribing an antibiotic derived from penicillin to an allergic patient, because this
information does not appear in his or her clinical record.
 Various studies have found that many more such incidents (near miss) occur than do actual
adverse events. In the specific case of prescribing pharmaceuticals, it is estimated that
approximately seven times more near misses occur than adverse events.

6. Accident.
Random, unforeseen and unexpected event which causes harm to the patient or any other type of
harm (material damage, harm to health care personnel, etc.).

7. Negligence.
Error which is difficult to justify due to a lack of knowledge or basic skills, failure to take
minimum precautions, carelessness, etc.

- Professional error in dentistry.

The errors in dental care may be of a human origin (in which a professional reaches an erroneous
decision or provides a deficient treatment), but in most cases their occurrence is to a great
degree dependent upon many contributing factors related with the system, which lead to a
chain of errors and end up causing harm to the patient.
OHSA is Occupational Health and Safety Act.
1. Patient safety definition.

2. How you will take alginate impression to the lab?

A. plastic bag
B. biohazard.
C. plastic bag with written biohazard.
Answer: A.
3. Flash sterilization:
A. put instrument in tray to sterilize and use after 24 hours.
B. Fast sterilization instrument in tray to be ready to use in operation.
C. sterilization instrument in warpage to be use after 24 hours.
D. sterilization instrument in warpage to use after 12 hours.
Answer: B.

Flash Sterilization is:

 Sterilization of Unwrapped Instruments (flash sterilization) steam sterilization
 The flash cycle on a steam sterilizer processes items to be used immediately.
 Use mechanical and chemical indicators for each unwrapped sterilization cycle (i.e., place an
internal chemical indicator among the instruments or items to be sterilized).
 It can be used in certain situation for semi-critical and critical instruments BUT NOT
implantable materials.

4. How can accurate sterilisation be achieved?

A. by changing strip indicator weekly and spore former indicator daily.
B. by changing strip indicator daily and spore former weekly.
C. by changing strip indicator weekly and spore former monthly.
Answer: B
 ADA recommends that dental offices monitor sterilizers at least weekly with biological
indicators.
 Use a biological indicator for every sterilizer load that contains an implantable device or
instruments used for an invasive procedure.
Monitor each load with mechanical and chemical indicators.
 Mechanical and chemical indicators do not guarantee sterilization;
however, they help detect procedural errors
 A chemical indicator should be used inside every package.
 Do not use instrument packages if mechanical or chemical
indicators indicate inadequate processing.
5. Sterilization means killing:
A. Bacteria and virus.
B. Bacteria, virus, fungus and protozoa.
C. Bacteria and fungus.
Answer: B.

6. Killing of bacteria is:

A. Bacteriostatic.
B. Bactericidal.
Answer: B.

7. Sterilization in autoclave:
A. 20-30 minutes at 121 c.
B. 2-10 minutes at 134 c.
C. a+b.
D. None.
Answer: C.

8. Sterilization in dry oven:

A. 1 hour at 160 c.
B. 90 minutes at 160 c.
C. two hours at 160 c.
D. None.
Answer: A and C.

 The proper time and temperature for dry heat sterilization is:
 160 °C (320 °F) for 60-120 min.
 2 hour 160
 1 hour 170
 191°C (375°F) for 6 min (unwrapped) to 12 min (wrapped) in case of High Velocity Hot Air
sterilisers
 Items should be dry before sterilization since water will interfere with the process.

9. Selection of steam heat (autoclave) over dry hot (oven):

A. Protein cell collagen degradation under high pressure
B. Safe effect on sharp instruments, no dull or corrosion
Answer: A.
  The proper time and temperature for steam heat sterilization is:
 121°C (250 °F) for 13-30 min according to DHA guidelines at 115 kPa (16.6 psi).
 134 °C (273 °F) for 3.5-12 min at 216 kPa (31.3 psi).

10. When we use 121c in autoclave, how much the pressure with pound?
A. 15

11. Minimum time to leave the air flow at beginning of the day in seconds:
A. 10 - 20
B. 30-40
Answer:
The correct answer is 120 second at the beginning of the day, and 30 seconds between patients.

Air and water lines should be flushed for a minimum of two minutes at the start of each day and
for 20-30 seconds between patients. There should be an extended flush at the beginning of
each session, particularly after a weekend or other break.
All dental equipment that supplies water to the oral cavity must be fitted with non-return valves

12. At the beginning of the operational day the dentist should run the water air spray for 3
min to prevent contamination by which microorganism:
A. Pseudomonas aeruginosa

 Waterline aerosols which contain Legionella pneumophila or Pseudomonas aeruginosa can

cause pneumonic diseases and wound infections.
 Water stagnation in dental unit waterlines creates biofilms and promotes the proliferation of
these microorganisms.

13. Dental caries is an endemic disease, means that the disease:

A. Occurs clearly in excess of normal expectancy.
B. Is habitually present in human population.
C. Affects large number of countries simultaneously.
D. Exhibits a seasonal pattern.
Answer: B.

14. Virus mostly infected to dental work team is:

A. HBV
B. HCV
C. FLU
Answer: C.

15. Most common transmission in dental clinic?

A. Droplet.
B. Aerosol.
C. Contact.
Answer: B
16. You told the assistant at the end of the day to check for water

17. Sterilizing an instrument and leaving it are different from an autoclave to another, in
autoclave B how many days would you leave the instrument or how many days can
storage the instruments after autoclave type B:
A. 21.→Type n autoclave
B. 30.→Type b autoclave
18. Type of autoclave used:
A. Hot oven autoclave.
B. Class b autoclave.
Answer: B.

19. What is the test name for detecting the virulence of bacteria?
A. Haemolysis.
B. Catalase.
Answer: A.
Haemolysis is the process of RBCs destruction, while Haemlysin is the material that causes
haemolysis.

Virulence methods fell into three basic categories:

 Enzyme analysis and Acid lability:
Chondroitinase, Coagulase, DNAse, Elastase, Fibrinolysin, Gelatinase, Haemolysin,
Hyaluronidase, Lecithinase, Lipase, Proteinase, Pyocyanin and Fluorescein.
 Antibiotic susceptibility analysis.
 Cytotoxicity potential.

20. Rideal walker test for:

Answer: Disinfection.

21. How can you reduce the contamination in skin?

A. disinfection
B. use of (chemical I don’t remember
C. Wearing personal preventive equipment.
D. wash 2-3 seconds.
Answer: C.
But if there is only one option, I will choose C.

Hand rub with alcohol-based hand rub (ethanol or isopropanol) for 20-30 seconds.
Hand wash is used only if the hands are visibly soiled, they are washed with soap and water for
15-20 seconds, however; the duration of the entire procedure is 40-60 seconds.

Personal Protective Equipment: When contact with blood or other body fluids is anticipated all
sterilization room associates must wear appropriate attire to prevent skin and mucous
membrane exposure. Personal Protective Equipment must be worn when working in the Dirty
Zone of the sterilization area.

22. PPE put on

A. Mask, eyewear, gloves.
B. Gloves, mask, eyewear
Answer: A.

23. Time for hand wash.

A. 10-15 sec.
B. 25-30 sec with alcohol.
C. 40-50 sec.
D. 50-60 sec with soap
Answer: D.

24. The role of good sterilization:

A. Washing, inspection, autoclave, drying, storage.
B. Inspection, autoclave, drying, storage.
C. Autoclave, drying, storage.
D. Autoclave is enough.
Answer: A.
25. Protocol of sterilization:
Answer: Washing, Ultrasound, Inspection, drying, packaging, autoclave, storage.
26. Autoclave relative to 100f dry oven:
A. the same time
B. slightly higher time
C. considerable higher time
D. less time.
Answer: D.

27. Why the moisture heat sterilization is better than dry heat sterilization:
A. Makes the instruments less rusty and blunt.
B. Needs more time and affects the proteins of the cell membrane.
C. Needs less time and affects the proteins of the cell membrane.
Answer: C.

28. Autoclave Principles:

A. Breaks the protein cell membrane at moderately low temp.
B. Breaks the protein cell membrane at very high temp.
Answer: A.

29. Which of following cause rust of instrument:

A. autoclave
B. Chemoclave
C. boiling water
D. dry heat
Answer: A.

30. Test for determining the efficiency of sterilizing agent is:

A. Fungi.
B. Virus.
C. Bacteria.
D. spores.
Answer: D.

31. Which of the following biologic tests is used to check the effectiveness of the sterilization
process?
A. Spore test.
B. Total bacterial count test.
C. Aseptic test.
Answer: A.
32. Spore test is what type of sterilization checkers, OR, the spore test is to assess the
sterilization process by killing microorganism
A. biological
B. bacterial
C. fungal
D. insect
Answer: A.

33. Which of the following doesn't have damage effect on hand piece?
A. Apply great pressure during use.
B. Infrequent moisturization.
C. Fall down of the head of the hand piece.
Answer: B.

34. One of these has no effect on the life span of handpiece:

A. Low Air in the compressor.
B. Trauma to the head of the hand piece.
C. Pressure during operating.
Answer: A.

35. Autoclaving technique is depending on:

A. Dry heat.
B. Steam heat.
C. Chemicals.
Answer: B.

36. Why immersion better than spraying (Infection Control)?

Answer: spraying is toxic.
For hydrophilic impression material, it is better to use spray to avoid distortion.

37. When we delay the cleaning and sterilization of instruments, we put it in:
A. Holding solution (detergent or water)
B. Sodium hypochlorite.
Answer: A.
38. The efficiency of the autoclave is decreased due to:
A. Sterilization without cleaning the instruments.
B. Over loading.
C. Dry blood on the instruments.
D. All of the above.
Answer: D.

39. The working surfaces in operation theatre should be disinfected especially for HIV, by
using:
A. Savlon.
B. Gamma radiation.
C. Hypochlorite solution.
Answer: C.
40. Patient vomit on the floor, what is the type of disinfectant to be used:
A. High
B. Low.
C. Medium
Answer: B.
To clean contact surface from blood…………….intermediate level of disinfectant.
To clean contact surface from saliva or vomit…..low level of disinfectant.
 Intermediate level of disinfectant: A 1:10 of 5.25%–6.15% sodium hypochlorite (i.e.,
household bleach) 
 Low level of disinfectant: A 1:100 dilution of 5.25%–6.15% sodium hypochlorite (i.e.,
household bleach).

41. Patient vomited, then the nurse wept it with towel paper, to which waste she should
must through it?
A. Hazard.
B. Contaminated
C. Infectious
D. toxic
Answer: B.
42. Which of following consider semi-critical?
A. instrument use in oral cavity.
B. dental chair and
Answer: A.
43. Mouth mirror is:
A. critical items.
B. semi critical.
C. non critical.
D. all of the above.
Answer: B.
44. In dental clinic patient rinsed his mouth and accidently spit on the dental chair and
floor instead on chair spittoon. Which type of disinfectant to be used for disinfection the
area?
A. light concentration
B. high concentration
C. follow manufacture instructions
D. something domestic or Household.
Answer: C.

45. After usage of sharp scalpels, needles what's the best management:
A. throw in a special container of sharp instruments (Sharp container).
B. sterilize and reuse.
C. Through in ordinary plastic waste basket.
Answer: A.

46. The most common activity associated with percutaneous injury of the dentist is:
A. Suturing.
B. Anaesthesia injection.
Answer: B.
47. The most common location of percutaneous injury among dentists is:
A. Hand.
B. Face.
C. Elbow.
D. Arm.
Answer: A.

48. A set of precautions designed to prevent transmission of HIV, hepatitis B virus (HBV),
and other bloodborne pathogens when providing first aid or health care is known as
____.
A. Asepsis
B. Infection control
C. Sterilization
D. Disinfection
E. Standard infection control procedures
Answer: E.

49. How to sterilize the instrument used for an HBV patient?

Answer: Follow the standard sterilization procedure.

50. Patient came for urgent care and he is already treated from HBV and no longer need
his medications. The management:
A. refuse the treatment.
B. send him to do HBsAb test.
C. treat him as a normal patient.
Answer: C.

51. How much time does HBV remains in a room with normal temperature?
A. few minutes.
B. 2 hours.
C. week.
D. Months.
Answer: C.

52. Healthy patient did regular visits to clinic and today came for check-up, the doctor
decides he will do hepatitis test why, because the patient has?
A. pale skin.
B. Yellowish skin with white eye.
C. Yellowish skin and eyes.
D. Other 2 choices.
Answer: C.

53. Patient has HBs Ag positive and HBs Ab negative, but HBc Ab positive:
A. Chronic
B. Acute
C. Immune by natural infection
Answer: B.
HBcAg (core): usually in the liver.
Anti HBc: means either it is an acute infection or recovered from infection
HBe Ag: indicates very infectious acute infection.
Anti HBe: indicates the onset of recovery in an individual with hepatitis B.

54. Patient infected by anthrax, after examination, doctor should disinfect his hand with:
A. 12 % chlorhexidine.
B. Antibacterial hand scrub.
C. Non antimicrobial soap.
Answer: C.
55. To kill HIV, we use all of the following EXCEPT:
A. NaoCl.
B. Ultraviolet chamber.
C. Autoclave.
D. Chemoclave.
Answer: B.
If there is an option of none of the above, I will choose it because UV is also a way to kill HIV but
the least effective.

56. Least effective method to kill HIV:

A. NaOCl
B. autoclave
C. chemoclave
D. ultraviolet chamber
Answer: D.

57. What is the time between the first onset of HIV virus and the appearance of acute
symptoms?
A. 1-5 years.
B. 9 - 11 years.
Answer: B.

58. What is the estimated incubation period of HIV infection?

A. 4 weeks.
B. 6 months.
C. 3 years.
D. 6 years.
E. 10 years.
Answer: E.

59. AIDS patient has asymptomatic broken tooth, what’s the management?
A. wear double gloves and face mask.
B. refer to infectious disease centre.
C. request CD4 test, and blood test.
Answer: C.

60. CD4 level in AIDs patient is:

A. <500.
Answer: A.

61. What’s the test used for HIV:

Answer: Elisa (also called EIA).

62. Doctor have a needle injury and the patient is diagnosed with HIV; the maximum time
allowed to get post exposure prophylaxis:
A. 5 weeks
B. 8 weeks
C. 6 weeks.
Answer: 72 hours.

63. Ideally, within how many hours should one receive medical attention for percutaneous
exposure to blood borne pathogens?
A. 2.
B. 4.
C. 6.
D. 8.
Answer: A.

64. Dental assistant vaccinated (she took all 3 doses) for HBV, and she got a needle stick
injury from patient positive for HBsAg, what to do?
A. immediately give Ig.
B. measure the antibody titre for AntiHBs.
C. only follow up.
Answer: B.

65. The ANTI-HBS titre to know if you are immune to HBS?

Answer: 100 mIU/ml.

66. Patient of HBV came to your clinic and during dental procedures, you had a severe
injury and bleeds a lot, what is your management?
1. Squeeze the wound but don’t scrub.
2. Wash the wound with water and put waterproofed plaster.
3. Asses the virulent of the patient and refer him for infectious disease consultant.
4. Ask him to apply pressure on the wound to stop bleeding.
A. 1+2+3.
B. 1+4.
Answer: A.

67. All regard to dentist has needle brick of HBV patient except:
A. Allow wound to bleed don't scrub.
B. Wash with water then put plaster.
C. Consult immunological unit.
D. pressure on the wound to stop bleeding.
Answer: D.

68. Doctor with no disease get injured and bleeds in the patient mouth, what he should do?
a) Don’t inform the patient but write it in the record
b) Reassure the patient to do nothing as the doctor is free of disease
c) inform the patient to post exposure follow up and refer accordingly
Answer: C.

69. A dentist is known free of diseases and follow infection control rules. While treating
patient injured his hands and bleeds inside patient mouth what to do?
A. don’t tell the patient.
B. tell the patient and assure him that he will not be infected.
C. rinse patient mouth.
D. tell the patient and assure him and follow up accordingly.
Answer: D.

70. When dentist use toflemire matrix, injured his finger and there is bleeding under
gloves:
A. put plaster without remove gloves
B. remove gloves and let bleed freely then wash with water and soap
Answer: B.
71. The most appropriate procedure when a glove has been punctured during a restorative
appointment is to:
A. wash the gloved hands using antimicrobial soap and complete the procedure.
B. change the glove as soon as possible.
C. put on an over-glove and complete the procedure.
D. complete the procedure as expeditiously as possible.
Answer: B.

72. For which of the following infectious diseases is there an effective immunization?
A. Hepatitis A virus (HAV)
B. Hepatitis B virus (HBV)
C. HIV/AIDS
D. Tuberculosis
E. Hepatitis C virus (HCV)
Answer: B.

73. HBV disinfection:

1) iodophors and hypochlorite.
2) formaldehyde.
3) Dettol / 100% ethyl alcohol.
4) Ethyl dioxide gas.
A. 1+2.
Answer: A

74. Patient with HBV came for emergency treatment. The management:
A. wear a surgical face mask and gloves.
B. wear a N95 mask and do the treatment.
Answer: A.
75. If you touched a drawer infected by HBV virus this is:
A. direct infection.
B. indirect infection.
C. Airborne.
D. Aerosol.
Answer: B.

76. Patient has cut in his hand and then touched handle and got HBV What is the mode of
transmission?
A. Direct
B. Indirect
Answer: A.

77. TB patient but it’s not infectious:

Answer: treat as a normal patient.

78. TB patient in active stage, when we do treatment?

A. Emergency case.
B. With rubber dam.
C. With mask.
D. Postpone the treatment.
Answer: A.

79. In a general dental practice setting, patients who are actively infectious with
Mycobacterium tuberculosis CANNOT be safely treated
A. unless there is adherence to standard precautions.
B. even if standard precautions are used.
C. unless a preoperative antimicrobial rinse is used in addition to standard precautions.
D. unless preoperative prophylactic antibiotic coverage and standard precautions are used
Answer: B.

80. Patient came to your clinic with active TB, what will you do?
A. postpone the treatment
B. treat him under high protective precautions
C. vaccine the staffs
D. treat as normal or other options
Answer: A.

81. TB patient with active disease, you started treat him what’s the management?
Answer: take extended or transmission-based precautions.

82. Patient with active TB but not on treatment. The dentist schedule from 8-12pm and give
appointment to the patient at 10pm what’s management:
a) Put the patient in isolated room.
b) Treat the patient as the last one of the day.
c) dentist should provide treatment to the patient as the other patients.
Answer: A.
83. TB patient under medication, what is the least time when can you book appointment for
him after medication?
A. 2 weeks.
B. 3 weeks.
C. 4 weeks.
D. 8 weeks.
Answer: D.

84. Which of the following conditions is highly indicated for the short therapy of DOTS and
is directly observed once in the clinic:
A. Tuberculosis.
B. HIV.
C. H1N1.
D. Mental Illness.
Answer: A.

85. TB patient said that he was diagnosed and started treatment, septum test not arrived
yet. How will you treat him?
a) Face shield
b) Face mask only
c) Oxygen mask
d) Open windows and face mask
e) Respiratory mask.
Answer: E.

86. How to treat patient cured from TB.

A. wearing mask.
B. respiratory mask (N95).
C. Face shield.
D. mask and open windows for ventilation.
Answer: A.

87. Patient when taken history he was infected with TB but now he is not infectious?
a) Standard precaution
b) Face mask
Answer: A.

88. Solution that breaks down latex in gloves:

A. Petroleum based.
B. alcohol based
Answer: A

89. Patient has hyperventilation in clinic. Most cause of hyperventilation in dental office:
A. Reduced (Low) CO2.
B. Increase (High) CO2.
C. Anxiety.
Answer: C.
90. You tell the nurse to put endodontic and surgical instrument for sterilization in?
A. single use rubber bag
B. sealed plastic paper
C. metallic box with led
D. stainless steel tray and wrapped with plastic paper
Answer: D.

91. Hygienists role in diagnosis and referring, they should be able to?
A. Diagnose.
B. Treat
C. Can differentiate between anatomic limitations and abnormalities on x-ray.
D. Refer.
A and D
92. The nurse told me there is patient outside with respiratory diseases then I have to take
precaution before I meet the patient by:
A. hand health and mask
B. Face shield and gloves.
C. Gown and hand gel
D. Eye protected and hand health
Answer: A.

93. Probiotics is:

A. disinfection kill Bacteroides
B. antibiotics for skin wounds
Answer: B.
94. Best method to reduce bacterial load before sterilization
A. Ultrasonic cleaner.
B. Disinfectant
C. Soap
D. UV
Answer: A.

95. Upright chair position, what is the underlying medical problem:

A. asthma.
B. congenital heart defect.
C. Seizure.
D. renal failure.
Answer: B.

96. Why do we clean instrument before sterilization?

A. Less time sterilization
B. Preserve instrument integrity.
C. Kill protein
D. Kill spores
Answer: B.

97. Dental burs become corroded ask assistant to?

A. immerse in H2O2 in closed container
B. H2O2 in non-closed container
C. other solution in 2 options of container may be (NaOCl)
D. 2% sodium nitrate in perforated container (Protect them from corrosion)
Answer: D.

98. _____ refers specifically to the process in which an antimicrobial agent destroys
(germicide) or inhibits the growth of (microbiostatic) pathogenic microorganisms on
inanimate surfaces.
A. Antisepsis
B. Microbacterial control
C. Sterilization and Disinfection.
D. Asepsis
Answer: C.

99. Which of the following guidelines are for disinfectants used in dental practice?
A. Have an EPA registration number
B. Kill Mycobacterium tuberculosis
C. Have an ADA seal of approval
D. Must be used according to guidelines
E. All of the above
Answer: E.

100. Which of the following statements about MSDSs is correct? Employees have the right to
know about on-the-job hazards.
A. MSDSs help to protect employees.
B. MSDSs contain information on hazardous materials, substance, and wastes.
C. MSDSs describe chemical hazards and how to work with chemicals safely.
D. All of the above
Answer: D.

101. Which of the following chemical agents is not a disinfectant?

A. Iodophors
B. Sodium hypochlorite
C. Synthetic phenol
D. Isopropyl alcohol
E. Glutaraldehyde
Answer: D.

102. Assistant wear ring and gloves over it, you told her to remove it:
A. not infection control
B. May tear the gloves
C. Difficult in washing her hand after procedure
Answer: B.

103. Dentist put his hand on dental chair:

A. disinfect and clean.
B. Sterilization
Answer: A.
Disinfect with low disinfectant.

104. Patient requests to take his extracted tooth with him, how you will sterilize the tooth
before give it to the patient?
A. 10% formalin.
B. Autoclaving.
C. 5.25% sodium hypochlorite.
Answer: C.

105. Patient with fracture tooth, after extraction he wants to take the tooth?
A. Autoclave.
B. Unnecessary process.
C. Low disinfection.
D. intermediate disinfection.
Answer: D.

106. Tooth was extracted and need it for preclinical:

Answer: if tooth doesn’t have amalgam: autoclave for 40 min, while amalgam containing teeth:
10% formalin for 2 weeks

107. Which of the following is the cause of immediate type allergic reaction to latex
products?
A. Accelerator.
B. Antioxidants.
C. Latex protein.
D. Nickel.
Answer: C.

108. Patient positions are:

A. Upright position.
B. Supine position.
C. Subsupine position.
D. All of the above.
Answer: D. dpending on the procedure and patient condition.
B &C are called reclined positions.

109. For the right-handed dentist seated to the right of the patient, the operator zone is
between:
A. 8 and 11 o'clock.
B. 2 and 4 o'clock.
C. 11 to 2 o'clock.
D. all of the above.
Answer: A.

110. For right-handed dentist, the static zone is between:

A. 8 - 11 o'clock.
B. 11 - 2 o'clock.
C. 2 - 4 o'clock.
D. all of the above.
Answer: B.

111. For right-handed dentist, the assistant's zone is between:

A. 8 - 11 o'clock.
B. 11 - 2 o'clock.
C. 2 - 4 o'clock.
D. all of the above.
Answer: C.

112. For right-handed dentist, the transfer zone is between:

A. 8 - 11 o'clock.
B. 4 - 8 o'clock.
C. 2 - 4 o'clock.
D. all of the above.
Answer: B.

113. Main complication that affect dentists working in a wrong position:

A. back pain.
B. cervical impairment.
C. ....... syndrome
Answer: A.

114. Note:
For right-handed dentist,
A) Operator Zone: 8 _ 11 o’clock.
B) Static Zone: 11 _ 2 o’clock.
C) Assistant Zone: 2 _ 4 o’clock.
D) Transfer Zone: 4 _ 8 o’clock.

115. Saliva ejector is placed:

A. At the side of working.
B. Under the tongue.
C. Opposite the working side.
D. b+c.
Answer: D.

116. HVE is placed (HVE is: High Volume Evacuator)

A. At the side of working.
B. Under the tongue.
Answer: A.

117. Grasping the HVE is by:

A. Thumb to nose grasp.
B. Pen grasp.
C. a+b.
D. none.
Answer: C.

118. You extract tooth with large amalgam restoration, how to manage the extracted tooth:
A. Autoclave and deep buried.
B. Sharp container.
C. Ordinary waste container.
D. Office container.
Answer:
 Tooth with amalgam to be disposed: It is illegal to incinerate teeth restored with amalgam
because of issues with mercury vapour emissions, therefore these teeth must not be placed in
medical waste or into sharps containers. Local regulations may apply on waste management
and disposal of teeth.
119. Note:
 Water flushing and discharge air 2-3 minutes in the morning every day.
 20-30 seconds between patients.

120. How should impressions and appliances be transferred to the Dental Laboratory?
Answer: you must be achieved with a mutually effective cross- infection control programme.

121. Which of the following provides the best environment to dental water line biofilm
formation?
Answer: Water stagnation.

122. What is the most important to pay attention in cleaning?

A. stagnated water line
B. ingoing water line
Answer: A.
123. A dentist was conducting interviews of potential applicants for the position of a dental
assistant and wanted to make sure the successful applicant was properly protected
against the hepatitis B virus. Which of the following is the best protection against
hepatitis B virus infection?
Answer: Vaccination.

124. A 60-year-old patient presented the Dental Clinic with a broken denture that was used
for three years and needs repairing. By inspecting the denture, the dentist found calculus
adherent to its surface. Which of the following is the proper method that should be
followed in the Dental Clinic prior to its delivery to the Dental Lab?
Answer: Ultrasonic cleaner, then in a sealed plastic bag.

125. Patient came to the clinic with broken complete denture, and you want to send it to the
lab to fix it, how should you clean it before sending it to the lab?
A. use diluted disinfectant
B. put it in autoclave
C. clean it with scaler
Answer: A.
126. When should an alcohol-based hand rub be used?
Answer: Only if no soil is visible on the hands

127. How to clean a suction tip for only one-use during surgery procedure?
A. Chx.
B. sodium hypochlorite.
C. tap water.
D. saline
Answer: C.

128. Minimum time for disinfecting dental chair with spray in minutes.
A. 1.5 minutes.
B. 3 minutes.
C. 5 minutes.
D. 10 minutes.
Answer: B.
Minimum time is 3 minutes.
Ideal time is 10 minutes.

129. Story about advising the assistant about the right method of sterilizing burs in order not
to get corroded.
A. submerge it in sodium nitrate in not perforated container.
B. submerge it in sodium nitrate in a perforated container..
Answer: B.

130. Minimum bacteria allowed in water pipe line in dental clinic.

A. less than 500.
B. 1000.
Answer: A.
131. When you can throw the sharp container?
Answer: when it ¾ full.

132. Sterilization biological monitor location?

Answer: Location in the chamber in steam sterilizer. This is typically on the bottom shelf near the
drain.

133. Infection control is?

A. Prevent infection from spread
B. Decrease infection
C. Decrease transmission of infection
Answer: A.

134. For sterilization of plier instrument which one is the least effective?
A. Ultrasonic
B. Dry heat
C. Steam heat
D. Chemical
Answer: A.

135. What is the type of sterilization applied on ligation/wires?

A. Autoclave

136. Cheek retractor sterilization by:

A. medium disinfection.
B. high disinfection.
C. Heat sterilization.
Answer: C.

137. When scrubs your hand?

A. between patient
B. When they become soiled
C. Before implant surgery
Answer: C.

138. Viability of microorganism:

 TB up to 4 h
 HBV 7days
 HIV 5-6 day

139. Droplet nuclei containing mycobacterium tuberculosis:

A. Do not cause infection.
B. Settle out of room air quickly.
C. Do not spread widely in the building.
D. Remain airborne for prolonged period.
Answer: D.