Teeth Whitening Whitening Safety & Sensitivity 1 — Questions and Answers
Question 1: Which patient group should AVOID tooth whitening products due to risk of enamel damage?
- Children under 16 with incompletely formed enamel (Correct answer)
- Adults over 60 with mild discoloration
- Patients with amalgam fillings
- Patients who drink coffee daily
Correct answer: Children under 16 with incompletely formed enamel
Enamel in children under 16 is still mineralizing, and high-concentration peroxide can cause irreversible damage to developing tooth structure.
Question 2: What is the most commonly reported side effect of teeth whitening?
- Temporary tooth sensitivity to temperature (Correct answer)
- Permanent enamel erosion
- Gum recession
- Tooth fracture
Correct answer: Temporary tooth sensitivity to temperature
Transient temperature sensitivity is reported by up to 65–78% of patients and typically resolves within a few days of completing treatment.
Question 3: How does peroxide cause tooth sensitivity during whitening?
- It penetrates enamel and dentin to stimulate pulp nerve fibers via fluid movement in tubules (Correct answer)
- It dissolves the enamel surface exposing dentin
- It dehydrates gum tissue causing referred pain
- It raises the temperature of the pulp above the pain threshold
Correct answer: It penetrates enamel and dentin to stimulate pulp nerve fibers via fluid movement in tubules
Peroxide diffuses into dentinal tubules and affects the hydrodynamic fluid movement that triggers A-delta nerve fibers in the pulp, causing sensitivity.
Question 4: A patient reports sharp, spontaneous pain that lingers for minutes after whitening. This most likely indicates what?
- Irreversible pulpitis requiring evaluation before continuing treatment (Correct answer)
- Normal temporary sensitivity from peroxide
- Gingival burn from gel overflow
- Sensitivity from a cracked filling
Correct answer: Irreversible pulpitis requiring evaluation before continuing treatment
Lingering, spontaneous pain is a classic sign of irreversible pulpitis, which requires the patient to stop whitening and seek dental evaluation immediately.
Question 5: What pre-treatment strategy can reduce sensitivity during a whitening course?
- Using a desensitizing toothpaste with potassium nitrate for 2 weeks before starting (Correct answer)
- Avoiding all foods for 24 hours before treatment
- Applying fluoride varnish to crown surfaces only
- Drinking cold water continuously during treatment
Correct answer: Using a desensitizing toothpaste with potassium nitrate for 2 weeks before starting
Pre-treatment with potassium nitrate toothpaste saturates dentinal tubules with ions that reduce nerve excitability, lowering sensitivity during whitening.
Question 6: Which condition makes teeth whitening contraindicated without prior restorative treatment?
- Exposed dentin from gum recession (Correct answer)
- Mild intrinsic staining from aging
- Yellow discoloration from coffee
- Hereditary pale tooth color
Correct answer: Exposed dentin from gum recession
Exposed dentin has no protective enamel layer, allowing peroxide direct access to sensitive nerve-rich tubules and potentially the pulp.
Teeth Whitening Whitening Safety & Sensitivity 1
Which patient group should AVOID tooth whitening products due to risk of enamel damage?