Study: NCT04356911

Intervention type: OTHER
Group type: PLACEBO_COMPARATOR
Intervention: PLACEBO (Negative Control)
Description: The group received in-office bleaching. A 45-minute application of 35% hydrogen peroxide gel (Whiteness HP, FGM, Joinville, SC) was carried. After whitening therapy, a water-soluble placebo gel (KY®, Johnson \& Johnson, SP, Brazil) was applied to the buccal surfaces of incisors, canines and premolars with the help of a Microbrush applicator (Microbrush, 3M ESPE, São Paulo , Brazil) for 10 minutes. Then, a rubber cup (Unid Microdont, São Paulo, SP, Brazil) mounted on a handpiece at low speed (Dabi Atlante, Ribeirão Preto, SO, Brazil) was used to rub the placebo gel for 20 seconds in each tooth surface. After washing the placebo gel, the laser tip was positioned at two points, apical and cervical, without emitting light (placebo), simulating the application of low-level laser therapy (LLLT).~This protocol was performed in 3 sessions, with an interval of seven days between them.

Intervention type: OTHER
Group type: EXPERIMENTAL
Intervention: FBM
Description: This group received photobimodulation with low level laser therapy (LLLT) of infrared spectrum with a wavelength of 808 nm in its active environment AsGaAl (Photon Lase III, DMC Equipamentos Ltda; São Carlos, SP, Brazil), at two points: cervical and apical region of the incisors, canines and premolars. 60 J / cm² was applied at each point for 16 seconds. The laser was applied in 3 sessions with a time interval of seven days between them.

Intervention type: OTHER
Group type: EXPERIMENTAL
Intervention: ESTRÔNCIO
Description: After whitening therapy, a toothpaste with 10% strontium chloride (Sensodyne Original, GSK, London, United Kingdom) was applied to the buccal surfaces of incisors, canines and premolars with the help of a Microbrush applicator (Microbrush, 3M ESPE, São Paulo , Brazil) for 10 minutes. Then, a rubber cup (Unid Microdont, São Paulo, SP, Brazil) mounted on a handpiece at low speed (Dabi Atlante, Ribeirão Preto, SO, Brazil) was used to rub the desensitizer for 20 seconds on each tooth , according to the manufacturer's specifications. The desensitizer therapy was realized in 3 sessions with a time interval of seven days between them.

Intervention type: OTHER
Group type: EXPERIMENTAL
Intervention: FBM+ESTRÔNCIO
Description: After whitening therapy, a 10% strontium chloride toothpaste (Sensodyne Original, GSK, London, United Kingdom) was applied to the buccal surfaces of whitened teeth with the help of a Microbrush applicator applicator (Microbrush, 3M ESPE, São Paulo , Brazil) for 10 minutes. Then, a rubber cup (Unid Microdont, São Paulo, SP, Brazil) mounted on a handpiece at low speed (Dabi Atlante, Ribeirão Preto, SO, Brazil) was used to rub the desensitizer for 20 seconds on each tooth , according to the manufacturer's specifications. After washing the desensitizer, the photobimodulation was realized with Low Level Laser Therapy (LLLT) of infrared spectrum with wavelength of 808 nm in its active environment AsGaAl (Photon Lase III, DMC Equipamentos Ltda; São Carlos, SP, Brazil), in two points: cervical and apical region of the incisors, canines and premolars. 60 J / cm² was applied at each point for 16 seconds. This protocol was performed in 3 sessions, with an interval of seven days between them.