Patchy results typically come from irregular gel application; use well-fitted trays and avoid overfilling to avoid streaks

https://andersonwmsf170.yousher.com/do-whitening-strips-really-work-a-dental-expert-s-point-of-view

Irregular outcomes typically originate from unequal gel application; usage well-fitted trays and prevent overfilling to avoid streaks, gum irritation, and lost product.