Irregular outcomes often come from irregular gel application; use well-fitted trays and avoid overfilling to avoid streaks
https://telegra.ph/The-Ultimate-Guide-to-Professional-Teeth-Whitening-What-to-Anticipate-04-17
Irregular results typically come from unequal gel application; usage well-fitted trays and prevent overfilling to avoid streaks, gum inflammation, and wasted product.