Response of Human Pulps to Different In-Office Bleaching Techniques: Preliminary Findings

Abstract

This study evaluated a whitening effect and the likely side effect (tooth sensitivity and pulp response) of human teeth subjected to different in-office bleaching (IOB) techniques and materials, mainly the presence of calcium in the IOB materials. A calcium-free (CF) and a calcium-containing (CC) 35% hydrogen peroxide (HP) gels were evaluated. The CF was refreshed every 15 minutes, three times (CF 3-15) or in a single 45-min application (CF 1-45) at one bleaching appointment. The CC was used only in a single 45-min application (CC 1-45). Each technique was applied in 5 mandibular incisors scheduled for extraction for different patients. In control group, no tooth bleaching was performed. The tooth colour (TC) and tooth sensitivity (TS) were recorded at baseline and after IOB. The teeth were extracted 2 days after the application of IOB and subjected to histological analysis. The data was submitted to appropriate statistical analysis (α=0.05). The changes of TC were similar between groups and statistically different from the control (p<0.05). However, TS of groups bleached with CF was statistically higher than that recorded for CC and the control (p<0.05). In CF 3-15 and CF 1-45 groups, the coronal pulp tissue exhibited partial necrosis associated with tertiary dentin deposition. In CC 1-45 group smaller area of necrosis occurred only in three bleached teeth in which tertiary dentin deposition was observed. The calcium-containing 35%HP gel could be preferable for in-office bleaching because it caused less tooth sensibility and pulp damage.

Effect of low‐level laser therapy combined with 5000 parts per million fluoride dentifrice on postbleaching sensitivity: A clinical, randomized, and double‐blind study

“…A previous study of rat molars has shown that H 2 O 2 causes necrosis in the occlusal third of coronary pulp after one bleaching session . A similar outcome was found in a study of human teeth . These changes may be related to the observation that most patients report postoperative sensitivity after dental bleaching techniques, especially after the use of high concentrations of H 2 O 2 …”

Concentration‐dependent effect of bleaching agents on the immunolabelling of interleukin‐6, interleukin‐17 and CD5‐positive cells in the dental pulp

“…The presence of calcium gluconate in bleaching gel minimizes the necrosis observed in human teeth after dental bleaching (Roderjan et al . ). This is because calcium can maintain a stable pH of the bleaching gel, besides preventing demineralization of the enamel, which would consequently reduce H 2 O 2 penetration and tooth sensitivity (Kossatz et al .…”

Randomized clinical trials of dental bleaching – Compliance with the CONSORT Statement: a systematic review

“…7,8,9 While laboratory testing is a very useful method to study the diffusion of the components of bleaching gels, such H 2 O 2 , into dental pulp, 10,11 clinical trials can provide reliable and direct evidence to guide clinicians in their choice of materials for in-office and at-home bleaching. 12,13,14,15 Hence, randomized controlled trials (RCTs) are considered the standard research design for the evaluation of health interventions.…”