Chapter 8 and 19

Question 1

Food and aging stains can usually be whitened in 2 to 4 months. Tetracycline stains can take up to 6 months to whiten.

Answer 1

d. The first statement is false; the second statement is true.
Rationale:
Food and aging stains can usually be whitened in 2 to 4 weeks. Tetracycline stains are the most resistant to whitening and can take up to 6 months to whiten.

Question 2

Teeth with tetracycline stains benefit most from the walking bleach method.

a. True
b. False

Answer 2

b. False

Question 3

Which of the following is not an active ingredient of professional dental whitening agents?

a. Sodium bicarbonate
b. Hydrogen peroxide
c. Carbamide peroxide
d. Sodium peroxyborate monohydrate

Answer 3

a. Sodium bicarbonate
Rationale:
Sodium bicarbonate is a mild abrasive used in some toothpastes and in air polishing but is not an active whitening ingredient in professional whitening materials. Hydrogen peroxide and carbamide peroxide are common and popular whitening agents in professional products. Hydrogen peroxide and sodium peroxyborate monohydrate are used in nonvital whitening.

Question 4

Whitening strips are the most widely used OTC whitening products.

a. True
b. False

Answer 4

a. True

Question 5

All of the following conditions are acceptable for enamel microabrasion except:

a. mild fluorosis.
b. remineralized white spot lesions.
c. hypermineralized areas.
d. hypomineralized areas.

Answer 5

d. hypomineralized areas.
Rationale:
The spots indicated for enamel microabrasion should be shallow enough to have an adequate thickness of enamel after the surface discoloration is removed via the microabrasion process. Hypomineralization is not an indication for enamel microabrasion because there is already a lack of adequate enamel in the area. Mild fluorosis, white spot lesions that have remineralized, and areas of hypermineralization are candidates for enamel microabrasion. Removal of the surface discoloration will likely leave a sufficient level of enamel post procedure.

Question 6

Wearing whitening trays at night can lead to clenching and grinding

a. True
b. False

Answer 6

a. True

Question 7

When making custom whitening trays, impressions should be poured up with dental plaster.

a. True
b. False

Answer 7

b. False

Question 8

In-office whitening procedures can be done in one 45-minute visit. Power-whitening procedures last indefinitely, while at-home, custom whitening tray procedures last 1 to 3 years.

a. Both statements are true.
b. Both statements are false.
c. The first statement is true; the second statement is false.
d. The first statement is false; the second statement is true.

Answer 8

c. The first statement is true; the second statement is false.
Rationale:
Most in-office whitening procedures can be completed in 45 minutes to an hour. Power whitening does not last indefinitely but rather 1 to 3 years just like at-home trays. The time involved in the whitening process is simply shortened with the power-whitening procedure.

Question 9

The FDA requires testing for all OTC whitening products. Because they are used in humans, manufacturing is highly regulated.

a. Both statements are true.
b. Both statements are false.
c. The first statement is true; the second statement is false.
d. The first statement is false; the second statement is true.

Answer 9

b. Both statements are false.
Rationale:
The FDA does not require testing for OTC whitening products, and therefore manufacturers are not regulated for these products

Question 10

Whitening can cause or increase tooth sensitivity. Peroxide can penetrate all the way through the enamel and dentin to the pulp in minutes, contributing to sensitivity and damage.

a. Both statements are true.
b. Both statements are false.
c. The first statement is true; the second statement is false.
d. The first statement is false; the second statement is true.

Answer 10

a. Both statements are true.
Rationale:
Sensitivity can be increased by whitening procedures. Sensitivity can come from peroxides passing through enamel into dentin tubules, and even into the pulp. Prolonged exposure can damage pulpal cells.

Question 11

Restorations bonded to recently whitened teeth are stronger because the tubules are open, allowing for better retention.

a. True
b. False

Answer 11

b. False

Question 12

Which of the following lightens teeth via a whitening process?

a. Galvanism
b. Oxidation
c. Corrosion
d. Imbibition

Answer 12

b. Oxidation
Rationale:
Whitening agents penetrate to the dentin, where oxygen free radicals are released and oxidize the stains, lightening the dentin. Galvanism is the electric current created between dissimilar metals, leading to corrosion. Imbibition is the uptake of fluids by a material.

Question 13

Your patient has had trauma to #9 from not wearing a mouth guard while playing soccer, resulting in a root canal and causing discoloration. He wants to know if there is anything that can be done for it, such as whitening. Which whitening method would you recommend for your patient?

a. In-office power whitening
b. Over-the-counter whitening strips
c. Walking bleach procedure
d. Custom whitening trays to use at home

Answer 13

c. Walking bleach procedure
Rationale:
When the pulp of a tooth dies, it can release by-products from the necrotic process, intrinsically staining teeth. The walking bleach method can only be done on nonvital teeth, as the whitening is done from the inside of the tooth by placing whitening solution into the pulp chamber via the endodontic access. Because of this, whitening procedures for extrinsic staining are ineffective in such a situation.

Question 14

The agent that helps remove stains in whitening dentifrice is usually which of the following?

a. Carbamide peroxide
b. Sodium bicarbonate
c. Hydrated silica
d. Sodium peroxyborate

Answer 14

c. Hydrated silica
Rationale:
Hydrated silica and calcium carbonate are used as abrasives in whitening dentifrices to remove surface stains. Carbamide peroxide is a professional whitening agent that is not used in whitening dentifrices. Sodium peroxyborate is used in walking bleach procedures and is not used in whitening dentifrices. Although sodium bicarbonate can be found in some dentifrices, it is not the main ingredient usually seen in whitening

Question 15

People who brux may have enlarged orbicularis oris muscles.

a. True
b. False

Answer 15

b. False

Question 16

The risk of jaw injuries increases by how much without an athletic mouth guard?

a. 2 times
b. 5 times
c. 10 times
d. Not much

Answer 16

a. 2 times
Rationale:
Not wearing an athletic mouth guard increases the chance for jaw injury by 1.5 to 2 times, which is why most states require their use in school contact sports.

Question 17

Mouth guards should be stored in an airtight container to prevent bacterial growth.

a. True
b. False

Answer 17

b. False

Question 18

Patients who grind their teeth heavily should have a soft guard to absorb the stress. Soft guards can be made by the assistant or hygienist.

a. Both statements are true.
b. Both statements are false.
c. The first statement is true; the second statement is false.
d. The first statement is false; the second statement is true.

Answer 18

d. The first statement is false; the second statement is true.
Rationale:
Patients who grind their teeth heavily should have a hard acrylic guard for durability. Soft guards can be fabricated in the office by the assistant, hygienist, or dentist. Alternatively, they can be sent to a laboratory for fabrication.

Question 19

Mouth guards absorb 100% of the energy from a hit to the mouth. Mouth guards can lessen or prevent concussions.

a. Both statements are true.
b. Both statements are false.
c. The first statement is true; the second statement is false.Incorrect Answer
d. The first statement is false; the second statement is true.

Answer 19

d. The first statement is false; the second statement is true.
Rationale:
Mouth guards absorb about 80% of the energy from a traumatic hit to the mouth. Because they provide cushioning, they can lessen or prevent concussions.

Question 20

Space maintainers are most often used in which situation?

a. A deciduous tooth is prematurely lost
b. For an implant
c. For partial dentures
d. For a bridge

Answer 20

a. A deciduous tooth is prematurely lost
Rationale:
While space maintainers are used to hold space from a lost tooth until an implant, bridge, or removable partial denture can be placed, they are most frequently used when a deciduous tooth is lost too soon to maintain the space for the permanent tooth.

Question 21

All of the following are risk factors for obstructive sleep apnea except:

a. being male.
b. being female.
c. chronic nasal congestion.
d. alcohol consumption.

Answer 21

b. being female.
Rationale:
Men are twice as likely to have sleep apnea than women, making being male, not female, a risk factor.

Question 22

Which of the following can be an adverse development from obstructive sleep apnea?

a. Hypertension
b. Heart attack
c. Stroke
d. All of the above

Answer 22

d. All of the above
Rationale:
Obstructive sleep apnea can result in serious health problems, such as hypertension, heart attack, heart failure, and stroke.

Question 23

Which of the following should be used in cleaning a mouth guard?

a. Denture cleaner
b. Liquid soap
c. Bleach
d. Mouthwash

Answer 23

b. Liquid soap
Rationale:
Liquid soap and a denture brush should be used to clean a mouth guard. Denture cleaner and bleach are far too strong and will degrade the material. Additionally, mouthwash with alcohol will also degrade the material and should not be used.

Question 24

Composite is used with thermoplastic orthodontic liners to help move teeth.

a. True
b. False

Answer 24

a. True

Question 25

Thermoplastic aligners for orthodontic treatment must be worn for 20 hours a day.

a. True
b. False

Answer 25

a. True

Question 26

Stock mouth guards are made of thermoplastic material. They can be purchased at the dental office.

a. Both statements are true.
b. Both statements are false.
c. The first statement is true; the second statement is false.
d. The first statement is false; the second statement is true.

Answer 26

b. Both statements are false.
Rationale:
Stock mouth guards are not made of thermoplastic material, removing the ability to somewhat mold to the individual’s mouth when warmed. Stock guards are not sold in dental offices because they offer the worst fit and least protection.

Question 27

Sleep apnea can cause people to wake 20 times an hour.

a. True
b. False

Answer 27

a. True

Question 28

Which of the following can be bought in stores?

a. Stock guards
b. Boil and bite guards
c. Custom-fit guards
d. Both a and b

Answer 28

d. Both a and b
Rationale:
Stock guards and boil and bite guards can be purchased over the counter in retail stores. Custom-fit guards require an impression and working model to fabricate a mouth guard custom fit to the individual.