NOCTI DENTAL ASSISTING PRACTICE
EXAM QUESTIONS AND CORRECT
ANSWERS (VERIFIED ANSWERS) PLUS
RATIONALES 2025
1. What is the primary function of the dental dam?
a) To protect the patient's eyes
b) To isolate the operative area and keep it dry
c) To prevent cross-contamination
d) To secure dental instruments
The dental dam isolates the tooth being worked on, preventing contamination
and keeping the area dry for procedures.
2. Which instrument is used to remove decay from a tooth?
a) Explorer
b) Cotton pliers
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,c) Excavator
d) Scaler
Excavators are designed specifically to remove softened decay from teeth.
3. What is the correct sequence for sterilizing dental instruments?
a) Clean, disinfect, sterilize
b) Clean, sterilize, store
c) Sterilize, clean, disinfect
d) Disinfect, sterilize, clean
Instruments must first be cleaned to remove debris, then sterilized to kill all
microorganisms before storage.
4. What type of impression material is commonly used for preliminary
impressions?
a) Alginate
b) Alginate
c) Polysiloxane
d) Polyether
Alginate is an inexpensive, easy-to-use material commonly used for preliminary
impressions.
5. The term "occlusion" refers to:
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, a) The biting or chewing surface of a tooth
b) The contact between upper and lower teeth when biting
c) The process of tooth decay
d) The gum surrounding a tooth
Occlusion describes how upper and lower teeth meet when the mouth is closed.
6. Which PPE is required during a dental procedure?
a) Gloves only
b) Mask and gloves only
c) Gloves, mask, and protective eyewear
d) No PPE is necessary
Standard precautions require gloves, mask, and protective eyewear to prevent
exposure to bodily fluids.
7. What is the name of the instrument used to hold the dental dam in place?
a) Frame
b) Clamp
c) Clamp
d) Forceps
The clamp secures the dental dam around the tooth to isolate it.
8. What is the purpose of fluoride treatment?
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EXAM QUESTIONS AND CORRECT
ANSWERS (VERIFIED ANSWERS) PLUS
RATIONALES 2025
1. What is the primary function of the dental dam?
a) To protect the patient's eyes
b) To isolate the operative area and keep it dry
c) To prevent cross-contamination
d) To secure dental instruments
The dental dam isolates the tooth being worked on, preventing contamination
and keeping the area dry for procedures.
2. Which instrument is used to remove decay from a tooth?
a) Explorer
b) Cotton pliers
1|Page
,c) Excavator
d) Scaler
Excavators are designed specifically to remove softened decay from teeth.
3. What is the correct sequence for sterilizing dental instruments?
a) Clean, disinfect, sterilize
b) Clean, sterilize, store
c) Sterilize, clean, disinfect
d) Disinfect, sterilize, clean
Instruments must first be cleaned to remove debris, then sterilized to kill all
microorganisms before storage.
4. What type of impression material is commonly used for preliminary
impressions?
a) Alginate
b) Alginate
c) Polysiloxane
d) Polyether
Alginate is an inexpensive, easy-to-use material commonly used for preliminary
impressions.
5. The term "occlusion" refers to:
2|Page
, a) The biting or chewing surface of a tooth
b) The contact between upper and lower teeth when biting
c) The process of tooth decay
d) The gum surrounding a tooth
Occlusion describes how upper and lower teeth meet when the mouth is closed.
6. Which PPE is required during a dental procedure?
a) Gloves only
b) Mask and gloves only
c) Gloves, mask, and protective eyewear
d) No PPE is necessary
Standard precautions require gloves, mask, and protective eyewear to prevent
exposure to bodily fluids.
7. What is the name of the instrument used to hold the dental dam in place?
a) Frame
b) Clamp
c) Clamp
d) Forceps
The clamp secures the dental dam around the tooth to isolate it.
8. What is the purpose of fluoride treatment?
3|Page
