Why the other options are wrong:

• He has been advised to do it for dental health reasons.: The dentist does not mention dental health reasons for whitening.
• He recently moved to Kitchener.: Moving to Kitchener is not mentioned in the conversation.
• His insurance plan will expire soon.: His insurance plan expiring is not discussed at all.

Correct Answer: It can cause short-term tooth sensitivity.

Why this is correct: The dentist says about half of patients notice some sensitivity for a day or two after in-office whitening. This temporary discomfort is a disadvantage, especially for someone who already has sensitive teeth. The take-home option causes sensitivity in only 15 to 20 percent of cases.

Why the other options are wrong:

• It requires daily treatment for two weeks.: Daily treatment for two weeks describes the take-home option, not in-office.
• It is not available in Kitchener.: The clinic is in Kitchener, and in-office whitening is available there.
• It does not change tooth colour very much.: The dentist says in-office whitening gives results of three to four shades lighter, so it does change colour.

Correct Answer: About two weeks.

Why this is correct: The dentist explains that the take-home trays involve using a gel at home for about two weeks, roughly 30 minutes a day. This is the timeline given for the full treatment. The dentist confirms it would finish in time before the six-week wedding date.

Why the other options are wrong:

• Three to four days.: Three to four days is too short and not mentioned as the treatment length.
• One long clinic visit.: One clinic visit describes the in-office option, not the take-home trays.
• Around six months.: Six months is mentioned for touch-up maintenance, not the initial treatment.

Correct Answer: Most plans do not cover it because it is cosmetic.

Why this is correct: The dentist says cosmetic whitening is not covered by OHIP or most insurance plans. Coverage under this customer’s particular plan is not established.

Why the other options are wrong:

• It is covered only for sensitive teeth.: Coverage based on sensitivity is not mentioned by the dentist.
• It is fully covered by OHIP.: The dentist says OHIP does not cover whitening, not that it is fully covered.
• Coverage depends on the patient's age.: Age-based coverage is not discussed in the conversation.

Correct Answer: They are less likely to worsen his tooth sensitivity.

Why this is correct: The dentist says the take-home trays use a lower gel concentration, which causes sensitivity in only 15 to 20 percent of patients compared to about 50 percent for in-office treatment. Since the patient already has sensitive teeth, this lower risk makes the trays a safer choice for him.

Why the other options are wrong:

• They require fewer lifestyle changes.: The dentist identifies lower gel concentration and reduced sensitivity as the tray advantage, without comparing the number of lifestyle changes.
• They produce faster results than in-office whitening.: The take-home trays take two weeks, so they are slower, not faster.
• They are much cheaper for the clinic to provide.: Cost to the clinic is not a factor the dentist mentions in the recommendation.

Correct Answer: Have impressions taken for custom trays.

Why this is correct: The patient says the take-home trays sound safer for him, and the dentist offers to take impressions that same day. The patient does not object, so having impressions made is the most likely next step. Custom trays are made from these impressions.

Why the other options are wrong:

• Schedule in-office whitening for the wedding week.: He chose the take-home option, not in-office whitening for the wedding week.
• Ask his insurance provider for special approval.: The dentist offers to take impressions today. Asking insurance for special approval is not the next step proposed.
• Delay whitening until after the wedding.: He clearly wants whitening before the wedding, not after.