Effect of an experimental desensitizing gel on bleaching-induced tooth sensitivity after in-office bleaching-a double-blind, randomized controlled trial.

OBJECTIVES: To evaluate the risk and intensity of tooth sensitivity (TS), and the efficacy of in-office bleaching after applying an experimental desensitizing gel composed of 10% calcium gluconate, 0.1% dexamethasone acetate, 10% potassium nitrate, and 5% glutaraldehyde. MATERIAL AND METHODS: In a split-mouth, double-blind, placebo-controlled study, 50 participants had their upper hemiarches randomized into experimental and placebo groups. Desensitizing and placebo gels were applied for 10 min before in-office bleaching (35% hydrogen peroxide, 1 × 50 min; two bleaching sessions; 1-week interval). TS was recorded immediately after bleaching, 1, 24, and 48 h after each session, with a 0-10 visual analogue scale (VAS) and a five-point numerical rating scale (NRS). The color was recorded in all groups at baseline, 1 week after each session, and 1 month after the end of bleaching using shade guide units (ΔSGUs) and a spectrophotometer (ΔEab, ΔE00, and ΔWID). RESULTS: Most participants (96%) felt some discomfort during treatment regardless of the study group. The odds ratio for pain was 0.65 (95% CI 0.1 to 4.1; p = 1.0). The intensity of TS did not differ between groups (p > 0.31), and it was only 0.34 VAS units lower in the experimental group. A significant color change occurred in both groups regardless of the group. CONCLUSIONS: The desensitizing experimental gel applied before in-office bleaching did not reduce the risk and the intensity of TS and did not affect color change. CLINICAL RELEVANCE: Although the experimental desensitizing agent with varying mechanisms of action did not jeopardize the color change, it did not reduce the risk or intensity of in-office bleaching. CLINICAL TRIAL REGISTRATION NUMBER: RBR-7T7D4D.

Evaluation of oral and perioral irritation and sensitization potential of a whitening gel and a whitening toothpaste containing potassium monopersulfate.

PURPOSE: Two clinical trials were conducted to investigate the oral and perioral irritation and sensitization potential of a tooth whitening leave-on-gel alone and in combination with a whitening toothpaste, each containing 1.0% of the active ingredient potassium monopersulfate (MPS). METHODS: Both clinical trials were Institutional Review Board (IRB) approved, double-blind, randomized, and parallel group designed studies. For the MPS leave-on gel study, 200 qualifying and consented subjects were randomly assigned to two groups: (1) 0.1% hydrogen peroxide (H2O2) gel pen (34 subjects); and (2) 0.1% H2O2 + 1.0% MPS gel pen (166 subjects). Subjects used the assigned products according to instructions provided and returned on Days 22 and 36 for oral and perioral tissue examination (pre-challenge). At the Day 36 visit, the subject applied the assigned gel on site (challenge) and received oral and perioral tissue examinations 1 and 24 hours following the application to detect any post-challenge tissue reactions. For the MPS toothpaste/MPS gel pen study, 200 qualifying and consented subjects were randomly assigned to three groups: (1) Placebo toothpaste + placebo gel pen (66 subjects); (2) 1.0% MPS toothpaste + 1.0% MPS gel pen (67 subjects); and (3) 1.0% MPS toothpaste + placebo gel pen (67 subjects). The study design and procedures were the same as those for the MPS gel pen study described above. RESULTS: For the MPS gel pen study, 192 subjects completed the study. None of the eight dropouts was related to the product use. The demographic data were comparable between the two groups. No evidence of tissue irritation and sensitization was detected in any subjects at any visit, and the findings were comparable between the groups. The detected and self-reported tissue issues were minimal and minor, and they were comparable between the two groups. For the MPS toothpaste/MPS gel pen study, 200 subjects were enrolled with 12 dropped from the study, resulting in an overall dropout rate of 6%. Of the 12 that did not complete the study, none were due to product-related use. The demographic data were comparable among the three groups. The detected and self-reported tissue issues were minimal and minor, and they were comparable among the three groups. CLINICAL SIGNIFICANCE: Potassium monopersulfate (MPS) at the active concentration of 1.0% in the tooth whitening leave-on-gel and the toothpaste plus the gel did not cause oral/perioral irritation nor sensitization.

Longterm abrasive and erosive effect of whitening toothpaste on dentin surface.

PURPOSE: To evaluate the amount of dentin loss following immersion in or toothbrushing with whitening toothpaste (WT) containing hydrogen peroxide (HP) and citric acid (CA). Additionally, the amount of dentin loss after brushing with a WT alone or in combination with a conventional toothpaste was assessed, and the effects of HP and CA solutions on the dentin surface were investigated. METHODS: Bovine dentin specimens (n= 350) were randomly assigned to seven solutions of various compositions as toothpaste: The specimens assigned to each solution were then further divided into five treatment groups (n=10 each) : Group A = 1-hour immersion in each solution (ES); Group B = 10,000 brushing in ES; Group C = 1-hour immersion in ES + 10,000 brushing in ES; Group D = 1-hour immersion in ES + 10,000 brushing in reference slurry (RS); Group E = 10,000 brushing in ES + 10,000 brushing in RS. The amount and pattern of dentin loss were determined, and the surfaces were observed using noncontact profilometry. RESULTS: The WT (pH 5.0) caused lower dentin loss than RS after a single brushing cycle; however, the extent of dentin loss after 1 hour of immersion in the WT was significantly greater than that in the RS. Among the specimens treated with WT, a significant difference in dentin loss was observed between Group C and Groups D and E (P< 0.05) but not between Groups D and E. The surfaces exposed to CAS1, CAPB, and WT exhibited U-shaped patterns of dentin loss after brushing or immersion, whereas a wedge-shaped pattern was observed in those that underwent brushing with the RS. CLINICAL SIGNIFICANCE: The effects (dentin abrasion) of a whitening toothpaste containing hydrogen peroxide and citric acid when used in combination with a conventional toothpaste were similar to those seen with the continuous use of a conventional toothpaste alone.

Gingival irritation in patients submitted to at-home bleaching with different cutouts of the bleaching tray: a randomized, single-blind clinical trial.

OBJECTIVES: This split-mouth randomized, single-blind clinical trial evaluated the gingival irritation (GI) of at-home bleaching with individual trays of different cutouts, as well as the tooth sensitivity (TS) and color change. MATERIALS AND METHODS: One hundred and twenty patients were randomized as to which side would receive the type of bleaching tray cutout: scalloped (in the gingival margin) and nonscalloped (extended from the gingival margin). The at-home bleaching was performed for 30 min with 10% hydrogen peroxide (HP) for 2 weeks. The absolute risk and intensity of GI and TS were assessed with a visual analog scale. Color change was assessed using a digital spectrophotometer and a color guide (α = 0.05). RESULTS: The proportion of patients who experienced GI was 57.5% (odds ratio 95% CI = 1.1 [0.7 to 1.8]), with no significant difference between groups (p = 0.66). The proportion of patients who experienced TS was 64.1% (odds ratio 95% CI = 1.0 [0.6 to 1.6]), with no significant difference between groups (p = 1.0). There is equivalence of scalloped and noscalloped groups for GI intensity (p < 0.01). Significant whitening was detected for both groups. Although some differences were observed between groups (CIELab and CIEDE00; p < 0.02), these were below of the considered clinically noticeable. CONCLUSIONS: The different cutouts of trays proved to be equivalent when regarding gengival irritation and tooth sensitivity when 10% HP for at-home bleaching was used. Significant color change was observed in both groups. However, significant differences detected between groups are not considered clinically noticeable. TRIAL REGISTRATION: Brazilian Clinical Trials Registry (RBR-2s34685). CLINICAL RELEVANCE: Scalloped or not, the individual trays for at-home bleaching could be considered a clinician's decision.

Is the use of a potassium nitrate dentifrice effective in reducing tooth sensitivity related to in-office bleaching? A randomized triple-blind clinical trial.

OBJECTIVE: The aims of this study were to evaluate whether the use of a dentifrice containing 5% potassium nitrate (KNO3 ) prior to and during in-office dental bleaching reduces bleaching-induced tooth sensitivity and affects bleaching efficiency. MATERIALS AND METHODS: Thirty-eight individuals were randomly distributed into two groups (n = 19). The experimental group performed toothbrushing using a dentifrice containing 5% KNO3 , one week before treatment and before the first and second bleaching sessions. In the control group, a placebo dentifrice without KNO3 was applied as described for the first group. Tooth sensitivity was recorded on visual analog scales (VAS) and numeric rating scales (NRS) immediately and up to 48 h after bleaching sessions. Color change at different time intervals, was evaluated with shade guide units (∆SGU) and a digital spectrophotometer (∆E CIELab 1976 and CIEDE2000) at baseline and 7, 15, and 30 days post-bleaching. Mann-Whitney test and t-test were used to evaluate TS intensity for NRS and VAS scales, respectively, and T-test was used for color difference evaluation. RESULTS: No significant difference in tooth sensitivity's absolute risk and intensity were observed between tested groups in any evaluated treatment time for NRS (p = 0.91) or VAS scales (p = 0.48). T-test showed no significant difference in both ∆E and ∆SGU tooth color among the experimental and control groups during the different evaluation times (p = 0.27). CONCLUSION: The use of a dentifrice containing 5% KNO3 does not prevent post-operatory tooth sensitivity but allows the same whitening efficiency as a regular dentifrice. CLINICAL SIGNIFICANCE: The use of a dentifrice-containing KNO3 did not prevent bleaching-induced tooth sensitivity when high-concentrated hydrogen peroxide was used for in-office bleaching.

Time-dependent efficacy and safety of tooth bleaching with cold plasma and H2O2 gel.

BACKGROUND: Hydrogen peroxide (H2O2) is the commonly used bleaching agent for teeth. But it is highly corrosive to teeth for the high concentration. The cold atmospheric pressure plasma has been witnessed a novel tooth bleaching technology and could help strengthen the bleaching effect when combined with H2O2. However, the efficacy and safety might highly correlated with processing time. The present study aims to evaluate the time-dependent efficacy and safety of tooth bleaching with cold plasma and H2O2 gel in vitro. METHODS: The H2O2 concentrations of the gel used in the study are 6%, 15%, 25% and 35%, respectively and the treatment time varies from 5 to 20 min. The tooth bleaching effect was evaluated by a Crystaleye Spectrophotometer and the overall change of the colorimetric value based on three independent measurements. Meanwhile, the microhardness, roughness and tooth temperature were evaluated. The surface morphology and the elemental composition were determined by scanning electron microscope and energy-dispersive X-ray spectroscopy. RESULTS: 5 min bleaching treatment contributed to 60% of the bleaching effect maximum, the 10 min effect was close to 15 min effect. Meanwhile, the microhardness reduced and roughness increased under a treatment which was longer than 20 min. Tooth pulp chamber temperature was keeping in a safe range within 20 min treatment. CONCLUSION: 5-10 min was the best treatment time from which we can get an ideal tooth bleaching effect and less influence on tooth enamel and pulp tissue when using cold plasma and H2O2 gel.

Clinical Testing of Walking Bleach, In-Office, and Combined Bleaching of Endodontically Treated Teeth.

Objective. The causes of internal posteruptive discoloration of teeth are bleeding, necroses, infections, and endodontic filling materials. The aim of this study was to establish the results of bleaching endodontically treated teeth using walking bleach, in-office, and combined techniques, using 30% carbamide peroxide and 35% hydrogen peroxide, as well as the effect of etiological factors, and the time elapsed after endodontic treatment on the success of bleaching. Materials and Methods. The research involved 30 endodontically treated teeth in healthy patients. Retroalveolar X-rays were taken to check the quality of root canal obturation. Endodontic treatment and obturation were carried out on the discolored non-vital teeth without any previous endodontic treatment. Before bleaching, two millimeters of the filling were removed from the root canal and the very entry into the canal was protected with glass ionomer cement. The teeth were divided into three groups, depending on the bleaching technique: walking bleach technique (10 patients), in-office technique (10 patients), and combined technique (10 patients). The teeth were bleached with 30% carbamide peroxide and 35% hydrogen peroxide. The bleaching procedure was repeated in all the patients three times. The color of all teeth was determined based on the Vita Classic guide before and after bleaching. The Χ2 square and Kruskal−Wallis tests were used to identify differences in teeth bleaching results. Results. A statistically significant difference (p < 0.05) was established between bleaching success and the time elapsed after endodontic treatment. There were no statistically significant differences observed between the bleaching success and etiological factors, bleaching techniques, or bleaching agents. Conclusions. The effectiveness of non-vital tooth bleaching is affected by the time elapsed after endodontic treatment.

Effectiveness of remineralization agents on the prevention of dental bleaching induced sensitivity: A randomized clinical trial.

OBJECTIVES: This study aims to compare the use of different remineralization agents before in-office bleaching for decreasing bleaching induced sensitivity. METHODS: A total of 64 volunteers were randomly divided into four groups. Before undergoing in-office bleaching with 38% hydrogen peroxide gel (three applications of 15 min each, one session), clinicians applied a placebo gel (control group), casein phosphopeptide-amorphous calcium phosphate (CPP-ACP), neutral sodium fluoride gel (NSF) or nano-hydroxyapatite solution (n-HAP) on all buccal surfaces of teeth. The gel was left undisturbed for 4 min. The efficacy of tooth whitening was assessed by determining the colour change using SGU. Patients recorded their tooth sensitivities on the VAS scale. Kruskal-Wallis test followed by Mann-Whitney U test was used to compare changes in tooth colour and intensity of tooth sensitivity between groups. RESULTS: Overall, there was no significant difference in shade change between the groups. Control and CPP-ACP groups showed significantly higher rates of hypersensitivity than NSF and the n-HAP group (p < 0.05). CONCLUSIONS: The use of a remineralization agent (n-HAP/NSF) before in-office bleaching did not affect the bleaching efficacy but did reduce tooth sensitivity. The before bleaching treatment use of an n-HAP solution can be suitable for reducing bleaching born sensitivity as well as commonly used NSF remineralizing gel before in-office tooth bleaching can reduce tooth sensitivity, the most common side effect associated with this procedure.

TRIM16 protects human periodontal ligament stem cells from oxidative stress-induced damage via activation of PICOT.

Periodontitis is a chronic inflammatory disease that result in severe loss of supporting structures and substantial tooth loss. Oxidative stress is tightly involved in the progression of periodontitis. Tripartite Motif 16 (TRIM16) has been identified as a novel regulatory protein in response to oxidative and proteotoxic stresses. The present study aimed to investigate the role of TRIM16 in human periodontal ligament stem cells (hPDLSCs) under oxidative stress. First, we found that the expression of TRIM16 decreased after exposure to H2O2. Then TRIM16 overexpression alleviated H2O2-induced oxidative stress by enhancing antioxidant capacity and reducing the amount of intracellular reactive oxygen species (ROS) and reactive nitrogen species (RNS). TRIM16 increased cell viability, inhibited cell apoptosis and the depolarization of the mitochondrial membrane potential in hPDLSCs. Furthermore, TRIM16 attenuated H2O2-induced suppression of osteogenic differentiation. Mechanistically, TRIM16 promoted the activation of protein kinase C (PKC)-interacting cousin of thioredoxin (PICOT), p-Akt and Nrf2, while knockdown of PICOT reversed TRIM16-mediated ROS resistance and decreased the expression of p-Akt and Nrf2. In conclusion, TRIM16 alleviated oxidative damage in hPDLSCs via the activation of PICOT/Akt/Nrf2 pathway, suggesting that TRIM16 could be a promising target to develop effective therapies for periodontitis.

Effects of whitening toothpaste and bleaching treatment on resin composite discoloration caused by cigarette smoke and electronic vapor aerosol.

PURPOSE: To compare the effects of whitening toothpaste and bleaching with 6% hydrogen peroxide (H2O2) on discoloration of dental resin composite caused by cigarette smoke (CS) and electronic vapor product (EVP) aerosol. METHODS: 40 resin composite discs were divided into three groups: 15 each for CS and EVP aerosol exposure and 10 for air exposure (control). Exposures were performed for 15 days, with daily brushing with regular toothpaste. Two whitening sessions, including 21 days of brushing with whitening toothpaste and 3 days of treatments with take-home bleaching (6% H2O2), were performed after the exposure. Color and gloss were assessed before exposure, at every 5 days of exposure, and after each whitening session. RESULTS: After 15 days of exposure, marked discoloration of resin composite was observed in the CS group (ΔE = 23.66 ± 2.31), minimal color change in the EVP group ((ΔE = 2.77 ± 0.75), and no color change in the control group. Resin composites exposed to CS did not recover their original color after treatment with whitening toothpaste ((ΔE = 20.17 ± 2.68) or take-home bleaching ((ΔE = 19.32 ± 2.53), but those exposed to EVP aerosol reverted to baseline after treatment with whitening toothpaste ((ΔE = 0.98 ± 0.37), and no further change in color was observed following take-home bleaching. The gloss of resin composites exposed to CS, EVP aerosol, and air decreased equally with exposure time. Brushing with whitening toothpaste recovered the gloss similarly in all groups, but no further change was observed following take-home bleaching. CLINICAL SIGNIFICANCE: Aerosol from electronic vapor products induced minimal discoloration of resin composites that can be completely reverted by brushing with whitening toothpaste alone. Bleaching with 6% H2O2 did not revert discoloration caused by cigarette smoke. Whitening toothpaste could help revert the decreased gloss of resin composites.

Surface damage of dental implant systems and ions release after exposure to fluoride and hydrogen peroxide.

OBJECTIVE: The aim of this study was to evaluate surface changes on dental implant systems and ions release after immersion in fluoride and hydrogen peroxide. METHODS: Ten implant-abutment assemblies were embedded in acrylic resin and cross-sectioned along the implant vertical axis. Samples were wet ground and polished. Delimited areas of groups of samples were immersed in 1.23% sodium fluoride gel (F) or in 35% hydrogen peroxide (HP) for 16 min. Gels (n = 3) were collected from the implant surfaces and analyzed by inductively coupled plasma mass spectrometry (ICP-MS), to detect the concentration of metallic ions released from the implant systems. Selected areas of the abutment and implant (n = 15) were analyzed by atomic force microscopy (AFM) and scanning electron microscopy (SEM). RESULTS: SEM images revealed surface topographic changes on implant-abutment joints after immersion in fluoride. Implants showed excessive oxidation within loss of material, while abutment surfaces revealed intergranular corrosion after immersion in fluoride. ICP-MS results revealed a high concentration of Ti, Al, V ions in fluoride after contact with the implant systems. Localized corrosion of implant systems could not be detected by SEM after immersion in hydrogen peroxide although the profilometry showed increase in roughness. ICP-MS showed the release of metallic ions in hydrogen peroxide medium after contact with dental implants. CONCLUSION: Therapeutical substances such as fluorides and hydrogen peroxide can promote the degradation of titanium-based dental implant and abutments leading to the release of toxic ions.

Pre-operative use of dexamethasone does not reduce incidence or intensity of bleaching-induced tooth sensitivity. A triple-blind, parallel-design, randomized clinical trial.

OBJECTIVES: This study evaluated the effect of the administration of pre-operative dexamethasone on tooth sensitivity stemming from in-office bleaching. MATERIALS AND METHODS: A triple-blind, parallel-design, randomized clinical trial was conducted on 70 volunteers who received dexamethasone or placebo capsules. The drugs were administered in a protocol of three daily 8-mg doses of the drug, starting 48 h before the in-office bleaching treatment. Two bleaching sessions with 37.5% hydrogen peroxide gel were performed with a 1-week interval. Tooth sensitivity (TS) was recorded on visual analog scales (VAS) and numeric rating scales (NRS) in different periods up to 48 h after bleaching. The color evaluations were also performed. The absolute risk of TS and its intensity were evaluated by using Fisher's exact test. Comparisons of the TS intensity (NRS and VAS data) were performed by using the Mann-Whitney U test and a two-way repeated measures ANOVA and Tukey's test, respectively. RESULTS: In both groups, a high risk of TS (Dexa 80% x Placebo 94%) was detected. No significant difference was observed in terms of TS intensity. A whitening of approximately 3 shade guide units of the VITA Classical was detected in both groups, which were statistically similar. CONCLUSIONS: It was concluded that the administration pre-operatively of dexamethasone, in the proposed protocol, does not reduce the incidence or intensity of bleaching-induced tooth sensitivity. CLINICAL RELEVANCE: The use of dexamethasone drug before in-office bleaching treatment does not reduce incidence or intensity of tooth sensitivity. CLINICAL TRIAL REGISTRATION NUMBER: NCT02956070.

Evaluation of the genotoxic potential of different delivery methods of at-home bleaching gels: a single-blind, randomized clinical trial.

OBJECTIVE: This single-blind, parallel, randomized clinical trial evaluated the genotoxic potential and effectiveness of 10% hydrogen peroxide (HP) in patients submitted to at-home bleaching. MATERIALS AND METHODS: Sixty young volunteers with maxillary incisors equal to or darker than M1.5 were included in the study. Patients were submitted to bleaching for 14 days (30 min/day) with one of the three 10% HP treatments: the bleaching agent was delivered in a bleaching tray (White Class, FGM), whitening strips (White Strips, Oral-b), or in prefilled disposable trays (Opalescence Go, Ultradent). The color change was evaluated with the Vita Bleachedguide, and the micronucleus test of exfoliative oral mucosa was carried out, starting from a count of 1000 cells, at the baseline, immediately after and 30 days after the end of the treatment. The micronucleus data were evaluated with the Kruskal-Wallis and Wilcoxon tests and color change with the two-way ANOVA test and the Tukey test (α = 0.05). RESULTS: Significant whitening was observed for all groups after 14 days (p = 0.001) and was maintained after 30 days, with no difference between groups (p = 0.42). The micronucleus count did not indicate genotoxic potential in any of the groups studied (p = 0.32), irrespective of the time intervals (p = 0.62). CONCLUSION: No genotoxic effects of 10% HP were observed in patients submitted to at-home bleaching systems (30 min/day for 14 days), even 30 days after the end of treatment. CLINICAL SIGNIFICANCE: It is safe to use different systems to deliver 10% HP during at-home bleaching according to the manufacturers' recommendations, with no risk of genotoxic effects applied.

Effect of gel replacement during in-office dental bleaching: a case report.

In-office dental bleaching allows the dentist to have greater control of the procedure and prevents patients from ingesting chemicals. To obtain optimum results, in-office bleaching usually requires a longer period of application as well as changes of the bleaching agent applied to the tooth surfaces at each appointment. The objective of this case report was to assess, by means of a split-mouth design in a single patient, the final tooth color and tooth sensitivity resulting from 2 different bleaching protocols: 1 application of 35% hydrogen peroxide for 45 minutes and 3 applications of 35% hydrogen peroxide for 15 minutes each. Neither the patient nor 5 individuals who were blinded to the techniques noted a difference in the final esthetic results of the 2 protocols immediately after the procedure. In addition, the patient reported that no tooth sensitivity was associated with either protocol. The results of dental bleaching on both sides were maintained after 15 days. The results shown in the present case report suggest that there may be no need to renew the gel during in-office dental bleaching.

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.

Antiseptics Commonly Used in Total Joint Arthroplasty Interact and May Form Toxic Products.

BACKGROUND: Multiple antiseptics have been described for use in total joint arthroplasty infection, and the use of multiple antiseptic solutions during a single operation has been described. Our clinical experience is that chlorhexidine (CHX) and Dakin's solution (NaOCl) interact and form a precipitate. The purpose of this study is to determine whether this reaction could be replicated in a laboratory setting, and to determine if other commonly used antiseptics also visibly react when mixed. METHODS: Four percent chlorhexidine gluconate (CHX), 0.5% sodium hypochlorite (NaOCl), 3% hydrogen peroxide (H2O2), and 10% povidone-iodine (BTD) solutions were obtained and all possible combinations were mixed. Any visible reactions were noted and recorded, and a literature search was performed to characterize the reaction and products. RESULTS: CHX and NaOCl, CHX and H2O2, and CHX and BTD reacted instantly, forming a precipitate. NaOCl and H2O2 reacted to produce a gas. NaOCl and BTD reacted and produced a color change. The literature review revealed that at least 2 of the reactions tested (CHX + NaOCl and NaOCl + H2O2) could result in byproducts toxic to humans. CONCLUSION: Surgeons must be aware of these interactions when using antiseptic solutions during procedures. Caution should be used combining or mixing antiseptics, and we recommend against concomitant introduction in a surgical wound.

Clinical Evaluation of 10% Hydrogen Peroxide on Tooth Sensitivity and Effectiveness in at Home Dental Bleaching.

AIM: The purpose of this study was to evaluate the dental effect and sensitivity of at-home dental bleaching with 10% hydrogen peroxide (H2O2). MATERIALS AND METHODS: Twenty volunteers with A2 or darker central incisors were selected for this study. Was used 10% H2O2 for thirty minutes twice a day, for two weeks. Shade evaluation was assessed visually by the value-oriented shade guide Vita Classical shade guide, Vita Bleachedguide 3D-MASTER and by the Easyshade spectrophotometer at baseline, during bleaching (first and second weeks), and post-bleaching (one month). The perceptions of sensitivity were recorded by the patients through the numerical rating scale (0 to 4) and 0 to 10 visual analog scales daily. Data from the shade guide units was subjected to a one way repeated measures (RM) analysis of variance (ANOVA) test (a = 5%). The overall AE, absolute risk and intensity of tooth sensitivity were calculated as well as the 95% confidence interval. RESULTS: The absolute risk of tooth sensitivity was 65% and the intensity was mild. Data from ASGU and AE after 1 month of bleaching for H2O2 10% showed significant whitening, 4 units for Vita Classical, 5 units for Vita Bleachedguide and 9.7 units for spectrophotometer. CONCLUSION: At-home bleaching using 10% hydrogen peroxide is effective in 14 days of bleaching. The most common adverse events were mild tooth sensitivity, and no subjects discontinued use early because of a treatment-related adverse event. CLINICAL SIGNIFICANCE: At-home dental bleaching with 10% hydrogen peroxide gel reduces the time of use of the tray, maintaining the effectiveness with low intensity of dental sensitivity. Brazilian clinical trials registry (REBEC) RBR-45xmzj.

[Medicaments and oral healthcare. Adverse effects of medicines and self care products on the gingiva]. / Serie: Medicamenten en mondzorg. Bijwerkingen van medicamenten en zelfzorgmiddelen op de gingiva.

Medications and self care products may have adverse effects on the gingiva. These adverse effects can be divided into inflammation, intrinsic discolouration, irritation, trauma, cytotoxicity, lichenoid reaction, and proliferation. This article deals with the first 6 types of adverse effects mentioned: a subsequent article will deal with the last type mentioned. Since contraceptives were introduced, there have been indications that they cause or promote gingivitis, but with the current contraceptives this adverse effect is rarely seen. Intrinsic discolouration of the gingiva has been reported when using Staloral®, minocycline, contraceptives and hydroxychloroquine. Irritation and trauma of the gingiva are seen when self care products containing carbamide peroxide or hydrogen peroxide are used for external tooth whitening, or which have analgesic potential, such as acetylsalicylic acid and hydrogen peroxide or oral rinses containing alcohol. Several cytostatics may induce apoptosis of keratinocytes in the gingiva. Oral rinses with antibacterial ingredients have cytotoxic potential. Lichenoid reactions have been reported due to the use of several (groups of) medications.

Oral mucosal irritation study in hamster to evaluate a therapeutic apparatus using hydrogen peroxide photolysis for periodontitis treatment.

We conducted an oral mucosal irritation study in hamsters to evaluate a therapeutic apparatus using hydrogen peroxide (H2O2) photolysis for periodontitis treatment (ISO 10993-Part 10, Annex B.3). The cheek pouches in 15 male hamsters were allocated to one of six groups. Group 1 received pure water treatment (control group). Group 2 received laser irradiation at 80 mW. Group 3 received 3% H2O2. Groups 4-6 received laser irradiation of 3% H2O2 at 80, 40, and 20 mW, respectively. The total treatment time was set at 7 min and treatment was repeated three times at approximately 1-h intervals. Macroscopic and microscopic histologic observations of the treated sites were performed immediately after each treatment and/or 24 h after the last treatment. The mean scores in macroscopic and histologic examinations in all six groups were 0. Accordingly, irritation indices calculated by subtracting the mean score in each experimental group from that in the control group (Group 1) were 0. Our results suggest that treatment with the apparatus has no mucosal irritation potential in hamster cheek pouches under test conditions simulating clinical conditions.

The effect of dental bleaching on pulpal tissue response in a diabetic animal model.

AIM: To evaluate pulpal tissue response after dental bleaching in normal and alloxan-induced diabetic rats. METHODOLOGY: Twenty-eight rats were divided into two groups of normoglycaemic and diabetic rats (n = 14). Diabetes mellitus (DM) was induced with alloxan. After DM confirmation, all rats were anaesthetized and dental bleaching was performed with 35% hydrogen peroxide (H2 O2 ) on the right maxillary molars for 30 min. Left molars were used as controls. Bleaching resulted in four hemimaxillae groups: normoglycaemic (N), N-bleached (NBle), diabetic (D) and D-bleached (DBle). After 2 or 30 days, the animals were euthanized and the hemimaxillae were removed, processed for histopathological analysis and stained with haematoxylin-eosin (HE), Masson's trichrome (MT) and picrosirius red (PSR). Results obtained within animals (normoglycaemic or diabetic rats) were submitted to Wilcoxon or paired t-tests, and between animal (normoglycaemic and diabetic rats), to Mann-Whitney test or t-tests. RESULTS: At 2 days, the NBle group had a mild inflammatory infiltration in the pulpal tissue, whilst the DBle had severe inflammation or necrosis (P < 0.05). At 30 days, no inflammation was present. However, a significant difference in pulp chamber area reduction by reactionary dentine deposition was found between the NBle and DBle groups (P < 0.05). At 2 days, fewer immature collagen fibres and more mature collagen fibres were noted in the NBle, D and DBle groups; this was significantly different when compared to the N group (P < 0.05). At 30 days, significantly fewer immature collagen fibres and more mature collagen fibres were noted in NBle compared with DBle group (P < 0.05). CONCLUSIONS: The inflammatory tissue response in rats' teeth after dental bleaching was greater in diabetic rats. Additionally, the increase in reactionary dentine deposition and mature collagen fibres observed in diabetic rats needs further evaluation to confirm the present results.