Question: how long do you leave opalescence 20 on your teeth?
Answer: Unless directed otherwise by your dentist, wear Opalescence 10% for 8–10 hours or overnight, Opalescence 15% for 4–6 hours, Opalescence 20% for 2–4 hours, and Opalescence 35% for 30 minutes. Remove excess gel with clean finger or soft toothbrush. Rinse twice; do not swallow rinsed gel.