Home Bleaching Time Calculator

At-Home Dental Whitening Time Calculator

Use this to work out how long an at-home tray whitening run will take from start to finish. The gel is carbamide peroxide at 10–22%, and you wear it in a custom tray that your dentist molds to your teeth. Inside the tray, carbamide peroxide splits into hydrogen peroxide at about a 1:3 ratio. So a 10% carbamide gel ends up releasing roughly 3.5% hydrogen peroxide against the enamel.

Most plans run 2–4 weeks, with daily wear somewhere between 1–8 hours. Weaker gels can stay in overnight, while the stronger ones cap out at 30–60 min. Color shows up slower than with in-office bleaching, but it tends to hold better, with less rebound and less sensitivity afterward. In Brazil you'll mostly see Whiteness Perfect (FGM) and Opalescence PF (Ultradent).

Applications

General dentists and aesthetic specialists lean on this when they supervise an at-home routine: it helps them brief patients on how long to wear the tray each day and roughly when the result should land. The regulation is ANVISA RDC 11/2003, and the FDA clears carbamide peroxide up to 22% for dental use. Before the tray is made, the patient should be checked for caries, exposed dentin and gingival recession.

FAQ

Why does it take longer than in-office? There's less peroxide, so the chromogens break down more slowly. The upside is that the slow diffusion is gentler on the enamel and leaves you with a color that lasts.

Can I buy over-the-counter whitening kits? In Brazil (RDC ANVISA 11/2003), off-the-shelf products top out at 6% hydrogen peroxide or 16% carbamide peroxide. Anything stronger needs a prescription.

What if sensitivity appears? Cut back the daily wear, take a day off, or put a desensitizing gel (5% potassium nitrate or fluoride) in the tray before the bleaching gel. If the pain sticks around, go back to your dentist.