16% Carbamide Peroxide Home Bleaching: Soft vs. Rigid Tray in a Randomized Blinded Equivalence Trial

The purpose of this clinical trial is to evaluate patient satisfaction, whitening efficacy, and the risk and severity of tooth sensitivity and gingival irritation after home bleaching with 16% carbamide peroxide using conventional (soft) trays or rigid trays. In addition, to assess whether there is a difference in patient satisfaction using a 0-10 visual analogue scale with conventional (soft) splints or rigid splints during home bleaching with 16% carbamide peroxide. To evaluate whether there is a difference in whitening efficacy using the VITA Easyshade V spectrophotometer and the VITA Classical and VITA Linearguide 3D-MASTER scales with conventional (soft) splints or rigid splints during home bleaching with 16% carbamide peroxide. To assess whether there is a difference in the absolute risk and intensity of tooth sensitivity using a visual analogue scale from 0 to 10 when using conventional (soft) splints or rigid splints during home bleaching with 16% carbamide peroxide and finally to assess whether there is a difference in the absolute risk and intensity of gingival irritation using a visual analogue scale from 0 to 10 when using conventional (soft) splints or rigid splints during home bleaching with 16% carbamide peroxide.

Inclusion criteria

• Patients over 18 years of age.
• Patients with vital teeth without restorations, single crowns, implants and/or bridges on the anterior teeth.
• Absence of dental caries in the teeth to be whitened.
• Patients with satisfactory oral hygiene and periodontal health, not undergoing periodontal maintenance and not using chlorhexidine mouthwashes. Patients with recession and no sensitivity were included.
• The absence of sensitivity was measured by applying air with the syringe of the dental equipment.
• Patients whose canines were at least A2-A3 in colour.

Exclusion criteria

• Patients who have already undergone bleaching (less than 5 years).
• Patients undergoing orthodontic treatment.
• Patients with white stains or changes in enamel development or staining.
• Patients with a history of trauma to the anterior teeth.
• Patients requiring internal bleaching.
• Smokers.
• Pregnant or lactating mothers.
• Patients with allergy to any of the bleaching components.
• Patients with oral mucosal changes (desquamative gingivitis, oral lichen planus, leukoplakia, etc.).
• Patients with medical conditions considered by the investigators to compromise the safety of the study or the individual patient.
• Patients with poor oral hygiene.
• Patients with a history of hypersensitivity.