Sensitivity and tooth whitening agents

Present status and future directions - Managing discoloured teeth

Managing tooth discolouration involves a range of different protocols for clinicians and patients in order to achieve an aesthetic result. There is an increasing public awareness in the appearance of their teeth and management of tooth discolouration may be inter-disciplinary and involve both vital and nonvital teeth. Vital teeth can be easily treated with low concentration hydrogen peroxide products safely and effectively using an external approach and trays. For endodontically treated teeth, the walking bleach technique with hydrogen releasing peroxide products is popular. However, there is an association with external cervical root resorption with higher concentrations of hydrogen peroxide of 30%-35%. There are also regulatory considerations for the use of hydrogen peroxide in certain jurisdictions internationally. Prosthodontic treatments are more invasive and involve loss of tooth structure as well as a life cycle of further treatment in the future. This narrative review is based on searches on PubMed and the Cochrane library. Bleaching endodontically treated teeth can be considered a safe and effective protocol in the management of discoloured teeth. However, the association between bleaching and resorption remains unclear although there is likely to be a relation to prior trauma. It is prudent to avoid thermocatalytic approaches and to use a base/sealer to cover the root filling. An awareness expectations of patients and multidisciplinary treatment considerations is important in achieving the aesthetic result for the patient. It is likely that there will be an increasing demand for aesthetic whitening treatments. Bleaching of teeth has also become increasingly regulated although there are international differences in the use and concentration of bleaching agents.

Home-based chemically-induced whitening (bleaching) of teeth in adults

BACKGROUND

With the increased demand for whiter teeth, home-based bleaching products, either dentist-prescribed or over-the-counter products have been exponentially increasing in the past few decades. This is an update of a Cochrane Review first published in 2006.

OBJECTIVES

To evaluate the effects of home-based tooth whitening products with chemical bleaching action, dispensed by a dentist or over-the-counter.

SEARCH METHODS

Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 12 June 2018), the Cochrane Central Register of Controlled Trials (CENTRAL; 2018, Issue 6) in the Cochrane Library (searched 12 June 2018), MEDLINE Ovid (1946 to 12 June 2018), and Embase Ovid (1980 to 12 June 2018). The US National Institutes of Health Ongoing Trials Register ClinicalTrials.gov (12 June 2018) and the World Health Organization International Clinical Trials Registry Platform (12 June 2018) were searched for ongoing trials. No restrictions were placed on the language or date of publication when searching the electronic databases.

SELECTION CRITERIA

We included in our review randomised controlled trials (RCTs) which involved adults who were 18 years and above, and compared dentist-dispensed or over-the-counter tooth whitening (bleaching) products with placebo or other comparable products.Quasi-randomised trials, combination of in-office and home-based treatments, and home-based products having physical removal of stains were excluded.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials. Two pairs of review authors independently extracted data and assessed risk of bias. We estimated risk ratios (RRs) for dichotomous data, and mean differences (MDs) or standardised mean difference (SMD) for continuous data, with 95% confidence intervals (CIs). We assessed the certainty of the evidence using the GRADE approach.

MAIN RESULTS

We included 71 trials in the review with 26 studies (1398 participants) comparing a bleaching agent to placebo and 51 studies (2382 participants) comparing a bleaching agent to another bleaching agent. Two studies were at low overall risk of bias; two at high overall risk of bias; and the remaining 67 at unclear overall risk of bias.The bleaching agents (carbamide peroxide (CP) gel in tray, hydrogen peroxide (HP) gel in tray, HP strips, CP paint-on gel, HP paint-on gel, sodium hexametaphosphate (SHMP) chewing gum, sodium tripolyphosphate (STPP) chewing gum, and HP mouthwash) at different concentrations with varying application times whitened teeth compared to placebo over a short time period (from 2 weeks to 6 months), however the certainty of the evidence is low to very low.In trials comparing one bleaching agent to another, concentrations, application method and application times, and duration of use varied widely. Most of the comparisons were reported in single trials with small sample sizes and event rates and certainty of the evidence was assessed as low to very low. Therefore the evidence currently available is insufficient to draw reliable conclusions regarding the superiority of home-based bleaching compositions or any particular method of application or concentration or application time or duration of use.Tooth sensitivity and oral irritation were the most common side effects which were more prevalent with higher concentrations of active agents though the effects were mild and transient. Tooth whitening did not have any effect on oral health-related quality of life.

AUTHORS' CONCLUSIONS

We found low to very low-certainty evidence over short time periods to support the effectiveness of home-based chemically-induced bleaching methods compared to placebo for all the outcomes tested.We were unable to draw any conclusions regarding the superiority of home-based bleaching compositions or any particular method of application or concentration or application time or duration of use, as the overall evidence generated was of very low certainty. Well-planned RCTs need to be conducted by standardising methods of application, concentrations, application times, and duration of treatment.

Attitudes of Students of Differenet Schools of University of Zagreb on Tooth Bleaching

OBJECTIVE

To compare the awareness that students from four different faculties within the University of Zagreb have of oral health and tooth bleaching procedure.

MATERIALS AND METHODS

The study included 158 subjects (both male and female) - 38 students from the School of Dental Medicine and 40 students from each of the following faculties: the School of Medicine, the Faculty of Economics and the Faculty of Civil Engineering. The respondents were asked to fill out the survey with multiple choices by marking the answers they considered correct.

RESULTS

Only 12% of the respondents followed the information on oral health. More than two thirds of all subjects brush their teeth twice a day, but there were no statistically significant differences between the subjects with respect to college or gender. More than half of the participants (55%) were satisfied, and 12% were completely satisfied with their dental appearance. About 80% of the respondents were aware of differences between teeth bleaching and teeth polishing procedures, with greater prevalence among Dental Medicine and Medicine students. 80% of all subjects would go to a dental office if they decided to whiten their teeth while less than a half (46%) of all the subjects believed that a tooth bleaching has some adverse side-effects.

CONCLUSIONS

There is a difference in knowledge on oral hygiene and tooth bleaching between the students from the School of Dental Medicine, the School of Medicine, the Faculty of Economics and those from the Faculty of Civil Engineering. Dental students have the best knowledge on tooth bleaching and oral health, which was in accordance with their educational guidance and level of education.

Evaluation of bleaching efficacy of 37.5% hydrogen peroxide on human teeth using different modes of activations: An in vitro study

INTRODUCTION

The aim of this in vitro study is to evaluate the role of light and laser sources in the bleaching ability of 37.5% H2 O2 on extracted human teeth.

MATERIALS AND METHODS

About 30 caries-free single-rooted maxillary central incisors were used for the study. Specimens were prepared by sectioning the crown portion of teeth mesiodistally, and labial surface was used for the study. Specimens were then immersed in coffee solution for staining. Color of each tooth was analyzed using Shadestar, a digital shademeter. Specimens were then divided into three groups of 10 each and were subjected to bleaching with 37.5% H2 O2, 37.5% H2 O2 + light activation, and 37.5% H2 O2 + laser activation, respectively. Postbleaching, the color was analyzed for all the specimens immediately and then after 1, 2, and 3 weeks intervals, respectively.

RESULTS

All the statistical analyses were done using SPSS version 17. Intra- and inter-group comparisons were done with Friedman test and Kruskal-Wallis ANOVA, respectively. Statistical analysis concluded with a significant improvement in their shade values from baseline in all the three groups. Halogen light activation and laser-activated groups showed comparatively enhanced bleaching results over no-activation group, though the difference was not statistically significant.

CONCLUSION

The results of the present study show that bleaching assisted with halogen light and laser showed increased lightness than nonlight activated group. Durability of bleaching results obtained postbleaching was maintained throughout the experimental trail period of 3 weeks for both halogen light and laser activation group, whereas no-light activation group presented with shade rebound after 2 weeks postbleaching.

Effect of Short-Duration, Localized Carbamide Peroxide Application to Remove Enamel Staining on Bond Strength of Resin Cement to Enamel

Objective Peripheral enamel staining is often noticed after removal of long-term veneer or crown provisional restorations. Application of carbamide peroxide (CP) easily removes the stain, but the potential for immediate bonding with a resin-based cement is questionable. This project tested the short-term, shear bond strength of a commercial, photo-curable, resin cement to bovine enamel after application of a 10% concentration of CP placed for different exposure times.

MATERIALS AND METHODS

Bovine enamel was flattened and polished. Surfaces had either no CP application (control), or 10% CP applied for 10, 20, or 30 seconds. Teeth were acid-etched, rinsed, dried, and controlled sized stubs of a commercial resin cement were photocured onto the treated surfaces. The shear bond strength of each specimen was determined using a universal testing machine, and results were compared using an analysis of variance at a preset alpha of 0.5 (n = 10/group).

RESULTS

No significant differences (p = 0.819) in shear bond strength were found among any CP cleaning treatments or the experimental (nontreated) control.

CONCLUSIONS

Short-term application of 10% carbamide peroxide prior to acid etching, to remove enamel stains in teeth prepared to receive ceramic veneers or crowns, does not reduce immediate shear bond strength of resin-based cement to enamel.

CLINICAL SIGNIFICANCE

Clinicians can confidently apply 10% CP for short-term, localized stain removal on enamel and not be concerned about affecting subsequent bond strength of a resin-based cement to enamel. (J Esthet Restor Dent, 2016).

Cytotoxic Effects of Hydrogen Peroxide on Human Gingival Fibroblasts In Vitro

In-office bleaching is a popular treatment in modern esthetic dentistry. However, bleaching agents sometimes accidentally adhere to the gingiva and peripheral tissues, even when applied by well-trained dentists. This can lead to transient pain and whitish changes in the gingiva. Although these symptoms disappear within several hours, the effects of bleaching agents on gingiva have not been well described in the literature. The present study aimed to elucidate the cytotoxic effects of a bleaching agent on cultured human gingival fibroblasts (HGFs). We performed a comprehensive analysis of the toxic effects of in-office bleaching agents on gingiva using cultured HGFs and DNA microarray. Survival rates of HGFs decreased with increases in the concentration of hydrogen peroxide, which became significant at concentrations of 1.5 × 10(-3)% or higher at every time point. Concentrations lower than 1.5 × 10(-3)% did not affect survival rates of HGFs. Cytotoxicity of hydrogen peroxide was significantly weakened by the addition of vitamin E. Stimulation by in-office bleaching agents triggered the proinflammatory cytokine tumor necrosis factor (TNF)-α cascade in gingival fibroblasts. As the TNF-α cascade can be inhibited by vitamin E additives, treatment with vitamin E may protect gingival fibroblasts against the toxic effects of an in-office bleaching agent. The present results suggest that local administration of vitamin E to gingiva before in-office bleaching may be useful for preventing gingival irritation due to accidental adhesion of a bleaching agent.

Safety issues of tooth whitening using peroxide-based materials

In-office tooth whitening using hydrogen peroxide (H₂O₂) has been practised in dentistry without significant safety concerns for more than a century. While few disputes exist regarding the efficacy of peroxide-based at-home whitening since its first introduction in 1989, its safety has been the cause of controversy and concern. This article reviews and discusses safety issues of tooth whitening using peroxide-based materials, including biological properties and toxicology of H₂O₂, use of chlorine dioxide, safety studies on tooth whitening, and clinical considerations of its use. Data accumulated during the last two decades demonstrate that, when used properly, peroxide-based tooth whitening is safe and effective. The most commonly seen side effects are tooth sensitivity and gingival irritation, which are usually mild to moderate and transient. So far there is no evidence of significant health risks associated with tooth whitening; however, potential adverse effects can occur with inappropriate application, abuse, or the use of inappropriate whitening products. With the knowledge on peroxide-based whitening materials and the recognition of potential adverse effects associated with the procedure, dental professionals are able to formulate an effective and safe tooth whitening regimen for individual patients to achieve maximal benefits while minimising potential risks.

Tooth-bleaching procedures and their controversial effects: A literature review

AIM

This review article will help clinicians improve their understanding of the history of bleaching procedures, bleaching types, components, mechanisms, and their effects on soft tissue, tooth structures, resin composite, and bonding.

METHODS

The controversial issues about bleaching procedures and their effects are reviewed. Additionally, the consequences of pre- and post-bleaching on the bonding potential of composite resin restorations to tooth structure are discussed.

CONCLUSION

The overall goal of the paper is to help reduce risks for patients.

Clinical trial of tooth desensitization prior to in-office bleaching

The aim of this clinical trial was to compare tooth sensitivity during and after bleaching with hydrogen peroxide gel following application of GLUMA Desensitizer PowerGel or placebo. Forty-six subjects with sound maxillary incisors and canines were enrolled. Tooth shades were determined by comparison with a Vitapan Classic Shade guide. GLUMA Desensitizer PowerGel and placebo were randomly applied to the labial surfaces of the left or right anterior teeth for 1 min, which were then rinsed and dried. Then, Opalescence Boost PF 40% gel was applied onto labial enamel for 15 min. Sensitivity scores [recorded on a 10-point visual-analog scale (VAS)] were determined before, at 5, 10, and 15 min during, and 1, 24, 48 h and 1 wk after, the bleaching treatment. Shades were determined postbleaching and after 1 wk. Prebleaching application of GLUMA Desensitizer PowerGel significantly reduced tooth sensitivity during and after bleaching when compared with treatment with placebo. The whitening effects immediately and 1 wk after bleaching were significant when compared with the prebleaching shades. In conclusion, tooth pretreatment with GLUMA Desensitizer PowerGel for 1 min prior to 15 min of in-office bleaching with 40% hydrogen peroxide gel was highly effective in reducing tooth sensitivity during and after bleaching.

Effect of laser irradiation on crystalline structure of enamel surface during whitening treatment with hydrogen peroxide

OBJECTIVE

This study is to evaluate the effect of laser activation on the whitening and crystalline structure of enamel surface during whitening treatment with hydrogen peroxide.

METHODS

Bovine teeth were treated with whitening gel containing 35% hydrogen peroxide. A whitening gel was applied on the enamel surface for a period of 5 min, and then irradiated using a diode laser (740 nm) during whitening treatment for 0, 30, 60, 120 and 180s for the GL0-W, GL30-W, GL60-W, GL120-W and GL180-W groups, respectively. The total whitening application time was 30 min for all groups.

RESULTS

Laser-irradiated enamel groups showed a similar lightness compared to the GL0-W group. The thickness of porous layer observed on the enamel surface of GL0-W group was decreased by increasing the laser irradiation time. While the Ca and P contents of the GL0-W group were lower than those of the non-whitening treated group (GL0-C), the Ca and P contents of the GL180-W group were similar to those of the GL180-C group. The enamel crystallinity was dramatically decreased by whitening treatment without laser irradiation. However, the decrease of crystallinity was protected by laser irradiation during whitening treatment. Raman measurement verified that laser irradiation could prevent the loss of mineral compositions on enamel and maintain its crystalline structure.

SIGNIFICANCE

The professional whitening treatment with hydrogen peroxide and diode laser activation improves not only the whitening effect but also protects the change of enamel structure compared to the treatment with only gel.

Erosion and abrasion on dental structures undergoing at-home bleaching

This review investigates erosion and abrasion in dental structures undergoing at- home bleaching. Dental erosion is a multifactorial condition that may be idiopathic or caused by a known acid source. Some bleaching agents have a pH lower than the critical level, which can cause changes in the enamel mineral content. Investigations have shown that at-home tooth bleaching with low concentrations of hydrogen or carbamide peroxide have no significant damaging effects on enamel and dentin surface properties. Most studies where erosion was observed were in vitro. Even though the treatment may cause side effects like sensitivity and gingival irritation, these usually disappear at the end of treatment. Considering the literature reviewed, we conclude that tooth bleaching agents based on hydrogen or carbamide peroxide have no clinically significant influence on enamel/dentin mineral loss caused by erosion or abrasion. Furthermore, the treatment is tolerable and safe, and any adverse effects can be easily reversed and controlled.

In vivo Spectrophotometric Assessment of the Tooth Whitening Effectiveness of Nite White 10% with Amorphous Calcium Phosphate, Potassium Nitrate and Fluoride, Over a 6-month Period

To clinically evaluate the effectiveness of Nite White 10% carbamide peroxide with amorphous calcium phosphate, potassium nitrate and fluoride over a 6-month follow-up period. Nite White was applied nightly for 14 days, according to the manufacturer's instructions. The color of teeth 11 and 21 of twenty one subjects was measured with a spectrophotometer (L(*); a(*); b(*)). Subjects were instructed to take note of any tooth sensitivity and gingival irritation. For all three components (L(*), a(*) and b(*)) statistical significant differences (p<0.05) in the values between base-line (pre-bleaching) and; after treatment, after 1-month, after 3-months as well as after 6-months were found (Wilcoxon Signed Rank Sum Test). Significant differences were also found amongst the ΔE(*) (ab) (0-14days) values and; ΔE(*) (ab) (0-1 month), ΔE*(ab) (0-3 months) and ΔE(*) (ab) (0-6 months). However, no significant differences were found between pairs of ΔE(*) (ab) (0-1 month), ΔE(*) (ab) (0-3 months) and ΔE(*) (ab) (0-6months). The decrease in ΔE(*) (ab) was the highest after 1 month (~30%). The highest decrease in L(*) was about 58% after 1 month. Over the 14-day treatment period tooth sensitivity was 24.5%.

CONCLUSIONS

Nite White ACP demonstrated significant tooth-whitening (unit increase = 5.29) with a low tooth sensitivity (25%) probably due to the presence of amorphous calcium phosphate, potassium nitrate, and fluoride. The whitening effect decreased the most after one month and then maintained well even after a 6 month period (units 3.89).

CLINICAL IMPLICATIONS

The product is a good tooth whitener with a color increase of about 5 units accompanied with a low sensitivity.

Efficacy and tolerability of two home bleaching systems having different peroxide delivery

The aim of this study was to investigate tooth whitening efficacy and oral side effects during bleaching with Whitestrips (WS) (6% hydrogen peroxide H(2)O(2) gel) and Vivadent Vivastyle (VS) (10% carbamide peroxide gel). Forty-seven subjects were included in this single blind, randomized, parallel group study. Application of WS was performed twice a day for 30 min. Trays filled with VS were worn for 60 min once a day. Tooth color was evaluated by measuring L*a*b* values before the study and after completion of the bleaching. Treatment tolerability was monitored throughout bleaching with an 8-week follow-up after completion of therapy. After 2 weeks both treatment groups demonstrated significant improvements in tooth color compared to baseline. A shift toward less yellow (-Deltab) and brighter (+DeltaL) tooth color was observed. Deltab amounted to -1.69 +/- 0.38 for WS and -1.20 +/- 0.34 for VS (mean value +/- SE). DeltaL was +1.55 +/- 0.41 for WS and +1.20 +/- 0.37 for VS. There was no significant difference between the two systems. No significant differences between the two bleaching systems were recorded for clinically observed signs or reported symptoms. Gingival irritation was observed in 13%, reported tooth hypersensitivities in 22% and reported gum irritation in 20% of the total study population. At an 8-week follow-up visit no adverse effects were observed. Both WS and VS demonstrated significant and comparable levels of tooth color improvement after 2 weeks. Each treatment caused similar levels of transient oral side effects.

External bleaching therapy with activation by heat, light or laser—A systematic review

OBJECTIVE

External bleaching procedures utilizing highly concentrated 30-35% hydrogen peroxide solutions or hydrogen peroxide releasing agents can be used for tooth whitening. To enhance or accelerate the whitening process, heat-activation of the bleaching agent by light, heat or laser is described in the literature. The aim of the present review article was to summarize and discuss the available information concerning the efficacy, effects and side effects of activated bleaching procedures.

SOURCES

Information from all original scientific full papers or reviews listed in PubMed or ISI Web of Science (search term: (bleaching OR brightening OR whitening OR colour) AND (light OR laser OR heat OR activation)) were included in the review.

DATA

Existing literature reveals that activation of bleaching agents by heat, light or laser may have an adverse effect on pulpal tissue due to an increase of intra-pulpal temperature exceeding the critical value of 5.5 degrees C. Available studies do not allow for a final judgment whether tooth whitening can either be increased or accelerated by additional activation.

CONCLUSION

Therefore, application of activated bleaching procedures should be critically assessed considering the physical, physiological and patho-physiological implications.

Vital tooth whitening

Vital tooth whitening, when administered correctly, is by all accounts one of the safest, most conservative, least expensive, and most effective aesthetic procedures currently available to patients. This article traces the evolution of the technology, describes what is known about the mechanism of action and explores such issues as toxicology and side effects associated with tooth whitening. The article also describes the various tooth-whitening systems, which include dentist-supervised night-guard bleaching, in-office or power bleaching, and bleaching with over-the-counter bleaching products. Combination treatments and light-activated treatments are also discussed. Finally, the article summarizes the areas of research needed in this field.

Effects of KTP Laser Irradiation, Diode Laser, and LED on Tooth Bleaching: A Comparative Study

OBJECTIVE

This in vitro study examines the whitening efficacy of a light-emitting diode (LED), a diode laser, and a KTP laser irradiation in dental bleaching by analyzing the change in color achieved from the treatment, the temperature increase induced in the pulpal cavity, as well as enamel microhardness measurement after treatment.

BACKGROUND DATA

Bleaching techniques achieved significant advances with the use of coherent or incoherent radiation sources to activate the bleaching agents.

METHODS

A hydrogen peroxide bleaching agent, Hi-Lite, was stimulated with an LED, a 980-nm diode laser at 0.8 W, or a 532-nm KTP laser at 1.0 W for 30 sec on 64 extracted human incisors. During irradiation, the temperature in the pulpal cavity was monitored. The color change was evaluated using the CIE L*a*b* color space measurement system, and Vikers enamel microhardness was tested after treatment.

RESULTS

A mean total color difference value (DeltaE*) greater than 5.0 was obtained in each group. KTP-laser-induced bleaching gave a significantly higher DeltaL* (8.35) after treatment (p < 0.01). Neither LED nor the two lasers produced significant differences in the enamel microhardness after treatment (p > 0.01). Mean maximal pulpal temperature rise was 2.95 degrees C for LED, 3.76 degrees C for KTP laser, and 7.72 degrees C for diode laser, respectively.

CONCLUSION

The results of this study suggest that KTP laser is effective at providing brighter teeth. According to the conditions used in this study, the LED and KTP laser induced a safer pulpal temperature increase when assisted with Hi-Lite bleaching gel.

Efficacy and oral side effects of two highly concentrated tray-based bleaching systems

The aim of this study was to investigate the tooth-whitening efficacy and oral side effects of the two tray-based bleaching systems Visalys whitening (VW) and Opalescence PF (OP). A stratified, randomised distribution of the subjects (n = 60) to two treatment groups was performed according to baseline tooth brightness (L* values) as determined by colourimeter and to the criteria smoker/non-smoker. Tooth colour was evaluated by measuring L*a*b* values generated from standardised digital image analysis with Adobe Photoshop of the facial surfaces of the right central maxillary incisor. Tooth hypersensitivity, with intensity graded from 0 (no hypersensitivity) to 10 (high hypersensitivity), was assessed chair-side using an air syringe. After bleaching therapy, both treatment groups demonstrated significant improvements in tooth colour (p < or = 0.05). A shift towards less yellow (-Deltab*) and brighter (+DeltaL*) tooth colour was observed. Deltab* was significantly higher in the OP group in comparison to the VW group, DeltaL* showed no significant difference between the both treatment groups (p < or = 0.05). After bleaching, the intensity of tooth hypersensitivity was increased significantly compared to baseline in both groups (p < or = 0.05), with no significant difference between the both groups. Both highly concentrated bleaching systems are effective as tooth-whitening systems, with few reported side effects such as transient tooth hypersensitivity.

Dental bleaching efficacy with diode laser and LED irradiation: an in vitro study

BACKGROUND AND OBJECTIVES

Bleaching techniques achieved significant advances with the use of coherent or incoherent radiation sources to activate the bleaching agents. This in vitro study compares the whitening efficacy of LED and diode laser irradiation using the two agents Opalescence X-tra and HP Whiteness.

STUDY DESIGN/MATERIALS AND METHODS

A total of 60 bovine incisors were randomly divided into six groups, three for each bleaching agent, receiving only agent, agent and LED (wavelength 470 nm), agent and 1.6 W diode laser (808 nm). The results of the irradiations were characterized using the CIEL*a*b* system.

RESULTS

Significant differences in the chroma value are obtained for the two whitening agents and for the different light sources. In terms of lightness, the association of Laser and Whiteness HP bleaching gel showed significantly better results than when the same agent was used alone or in combination with LED.

CONCLUSIONS

Best overall results are obtained with the Whiteness HP and Laser association.

Desensitizing agent efficacy during whitening in an at-risk population

BACKGROUND

Nightguard vital bleaching (NGVB) has gained acceptance among dentists and patients as a simple and effective procedure to lighten discolored teeth. Although the efficacy and predictability of NGVB have been well established, it has been documented that patients undergoing the procedure may experience side effects such as tooth sensitivity (TS) and gingival irritation (GI). A previous NGVB study suggested that selected participants might benefit from a regimen of a desensitizing agent (DSA) to decrease or prevent TS during whitening.

PURPOSE

The purpose of this study was to determine whether the daily use of an active DSA (UltraEZ, Ultradent Products Inc., South Jordan, UT, USA) during NGVB would decrease TS in a population at risk for TS when compared with a placebo.

MATERIALS AND METHODS

Forty subjects participated in this single-blind randomized clinical trial. All participants had indicated that they had preexisting TS or other risk factors for TS during NGVB. To evaluate TS caused by the tray alone, participants wore custom-fitted maxillary whitening trays containing no DSA or whitening solution during week 1. Next, participants were randomly assigned to apply either the active DSA or placebo daily for 14 days in the trays for 30 minutes prior to whitening. The placebo was the same formulation as UltraEZ but without the desensitizing agents (3% potassium nitrate and 0.11% by weight fluoride ion). The bleaching solution was a 10% carbamide peroxide whitening solution (Opalescence, Ultradent Inc.). Post treatment, participants were followed up for 1 week, during which time they used neither trays nor solutions. Throughout the study, participants completed a daily diary to record their perceptions of TS and the time spent wearing the tray with the whitening solution.

RESULTS

Forty-one percent of the active group had at least 1 day of TS during treatment compared with 78% of the placebo group. The difference was statistically significant (p = .027) using the two-tailed Fisher exact test.

CLINICAL SIGNIFICANCE

This study suggests that the use of an active 3% potassium nitrate and 0.11% fluoride desensitizing agent for 30 minutes prior to whitening may decrease tooth sensitivity when compared with a placebo in a population at risk for tooth sensitivity.