We recommend starting with applications of 45 minutes – 1 hour and then working your way up to applications of 3 hours as your teeth are comfortable. If you have sensitive teeth, you will want to stick with shorter sessions and may need to skip a day. It is highly recommended by dentists and hygienists that customers should use desensitizing gel for 20 minutes after each teeth whitening session.
Note: Every time you whiten, you are removing years of stains so be patient! If you have to do shorter sessions (but more of them), its ok. Once you have the results you're looking for, it takes very little to maintain those results for life!