If you clench or grind, discuss it before whitening; enamel wear and exposed dentin can increase level of sensitivity

https://blogfreely.net/dernesvhbz/foods-that-discoloration-your-teeth-and-how-to-fight-them

If you clench or grind, discuss it before whitening; enamel wear and exposed dentin can increase level of sensitivity, needing tailored procedures and gentler gels.