Effect of Different Desensitizing Agents on Post-bleaching Hypersensitivity and Shade Stability

The Effect of Different Desensitizing Agents on Post-bleaching Hypersensitivity, Shade Stability and Surface Properties of Bleached Enamel. An In-vitro and In-vivo Study.

This study compared the effect of four different desensitizing agents on shade stability and dental hypersensitivity following dental bleaching procedure. The follow-up periods ranged from 24 hours to 1 year.

This study was conducted to assess the effectiveness of 4 different desensitizing agents used after dental bleaching regarding dental hypersensitivity and shade stability. It was a double-blinded randomized clinical trial.

The ethical approval was obtained in May 2020 by the Research Ethics Committee an Institutional Review Board, Faculty of Dentistry, Ain Shams University (FDASU-REC).

The number of patients was determined according to G-Power program with a power (1-β error) of 0.8 (Power = 80%), and 95% confidence level (α = 0.05) using a two-sided hypothesis test. According to sample size calculation, 40 patients were needed for this study (n=10 per group).

Patients were selected according to inclusion and exclusion criteria and were randomly assigned into 4 groups according to the desensitizing agent used. The 4 desensitizing agents were: After Whitening Mousse, Mi Paste Plus, Hydroxyapatite and Fluoride (ReminPro) and PAMAM.

Patients signed an informed consent and received a detailed explanation of the study procedures. Baseline dental shade was recorded using Vita Easy-Shade spectrophotometer and Vita Classical Shade guide. Baseline sensitivity was assessed and recorded using a VAS.

All patients received dental bleaching using In-office chemically activated Power Whitening YF (WHITEsmile, Germany) followed by a desensitizing procedure using the desensitizing agent assigned to the specific experimental group.

Dental shade and dental hypersensitivity was assessed at different follow-up appointments; 24-hours, 3 days, 1 week, 1 month, 3 months, 6 months, 9 months and 1 year following the procedures.

Assessment of these variables at follow-up appointments was performed by 2 external assessors, and patients were blinded to the type desensitizing agent used.

Inclusion Criteria:

• Participants with their entire upper and lower teeth, from right first premolar to left first premolar, present and sound, without restorations or periodontal disease.
• The participants had low-caries index scores.
• Participants had teeth with a Vita-color shade of A2 or darker.
• Cooperative behavior patient and medically free.
• Patient ages between 18 to 40 years old

Exclusion Criteria:

• Serious medically compromised patients.
• Smoking, alcoholism.
• Hypersensitivity to the agents used in the study.
• Lactating, pregnant patients.
• Patients with serious oral diseases, as acute necrotizing gingivitis, acute gingiva stomatitis, or those undergoing orthodontic treatment.
• Patients with dental enamel cracks.
• Patients who've had previous bleaching treatments