In-office bleaching with complete cervical third protection protocol: A split-mouth, double-blind, randomized clinical trial

Purpose: To evaluate the bleaching sensitivity and the bleaching effectiveness of in-office bleaching, following a protocol of complete cervical third protection with gingival dam in comparison with a traditional manner of applying gingival dam (used only in the gingival sulcus area). Methods: 35 participants were selected for this double-blind split-mouth randomized clinical trial. The control group received the gingival barrier in the traditional manner, and in the experimental group the barrier was extended by about 3 mm to include the cervical region. The bleaching agent was applied in two sessions. The risk and intensity of bleaching sensitivity were assessed using two scales. The bleaching effectiveness was evaluated with a digital spectrophotometer with the tip placed in the cervical area. The absolute risk of bleaching sensitivity was compared by the McNemar's test and bleaching effectiveness (Delta Eab, Delta E00 and Delta Wi) and intensity of bleaching sensitivity was evaluated by Wilcoxon-paired test (alpha=0.05). Results: No significant difference at risk (P= 1.0) and intensity of bleaching sensitivity (P> 0.45) was seen between groups. After 30 days, bleaching effectiveness had no statistical difference between the groups (P> 0.09). CLINICAL SIGNIFICANCE: Extending the barrier in the cervical region of teeth did not reduce the risk and intensity of bleaching sensitivity, nor jeopardize the bleaching effectiveness.

Automated summary

The study on 35 participants found that extending the gingival barrier to the cervical region did not reduce the risk and intensity of bleaching sensitivity, nor impact the bleaching effectiveness.