Potassium Nitrate and Post-bleaching Sensitivity

"* 15 days before and during the period of bleaching sessions: Tooth paste used will be normal (Colgate).~* Teeth will be cleaned using rubber cups associated to pumice and water;~* Relative isolation with roller cotton will be done;~* Prior to each bleaching session, the patients will receive the placebo gel application on vestibular surface, for 10 minutes.~* Gingival dam will be performed using a fluid resin.~* A 35% hydrogen peroxide based bleaching agent will applied on the vestibular surface of teeth, remaining for 40 minutes."

"* 15 days before and during the period of bleaching sessions: Tooth paste used will be normal tooth paste (Colgate).~* Teeth will be cleaned using rubber cups associated to pumice and water;~* Relative isolation with roller cotton will be done;~* Prior to each bleaching session, the patients will receive the 5% Potassium Nitrate gel application on vestibular surface, for 10 minutes.~* Gingival dam will be performed using a fluid resin.~* A 35% hydrogen peroxide based bleaching agent will applied on the vestibular surface of teeth, remaining for 40 minutes."

"* 15 days before and during the period of bleaching sessions: Tooth paste used will be Potassium Nitrate containing (Sensodyne).~* Teeth will be cleaned using rubber cups associated to pumice and water;~* Relative isolation with roller cotton will be done;~* Prior to each bleaching session, the patients will receive the placebo gel application on vestibular surface, for 10 minutes.~* Gingival dam will be performed using a fluid resin.~* A 35% hydrogen peroxide based bleaching agent will applied on the vestibular surface of teeth, remaining for 40 minutes."