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.

Effect of photobiomodulation with low-level laser therapy combined with potassium nitrate on controlling post-bleaching tooth sensitivity: clinical, randomized, controlled, double-blind, and split-mouth study.

OBJECTIVES: To evaluate the effect of photobiomodulation with low-level laser therapy (PBM-LLLT) combined with 5% potassium nitrate (KNO3) on controlling tooth sensitivity (TS) after in-office tooth bleaching. MATERIALS AND METHODS: Fifty volunteers were selected based on the inclusion and exclusion criteria and were randomly allocated into four groups: G1 (control): placebo gel application, 35% hydrogen peroxide bleaching (HP35) and mock PBM-LLLT without light emission; G2: placebo gel application, bleaching with HP35 and PBM-LLLT; G3: application of KNO3, bleaching with HP35 and mock PBM-LLLT; and G4: application of KNO3, bleaching with HP35 and PBM-LLLT. A pain assessment questionnaire was used to evaluate TS during the 21 days of treatment. The Friedman test was used for intragroup analysis, and the Wilcoxon and Mann-Whitney tests were used for intergroup comparisons. RESULTS: The intragroup evaluation showed significant differences among the evaluation times in all groups (p ≤ 0.05). The highest pain sensitivity levels were recorded on the 1st, 8th, and 15th days. In G1, TS manifested for up to 3 days after each bleaching session, while G2, G3, and G4 presented TS only on the days of the bleaching sessions. Intergroup analysis showed that TS manifestation differed significantly between G1 and the other groups (p ≤ 0.05) but did not differ significantly among G2, G3, and G4 (p ≥ 0.05). CONCLUSION: PBM-LLLT and KNO3 are effective at reducing pain sensitivity after tooth bleaching, but no synergistic effect between these treatments was observed for the different evaluation periods. CLINICAL RELEVANCE: The effect of PBM-LLLT combined with KNO3 on post-bleaching tooth sensitivity is similar to their individual use alone.

Tooth sensitivity with a desensitizing-containing at-home bleaching gel-a randomized triple-blind clinical trial.

OBJECTIVES: Desensitizing agents are usually included in the composition of bleaching agents to reduce bleaching-induced tooth sensitivity (TS). This randomized clinical trial (RCT) evaluated the risk and intensity of TS and color change after at-home bleaching with a desensitizing-containing (3% potassium nitrate and 0.2% sodium fluoride) and desensitizing-free 10% carbamide peroxide (CP) gel (Whiteness Perfect, FGM). METHODS: A triple-blind, within-person RCT was conducted on 60 caries-free adult patients. Each participant used the gel in a bleaching tray for 3 h daily for 21 days in both the upper and lower dental arches. The absolute risk and intensity of TS were assessed daily through the 0-10 VAS and NRS scale for 21 days. Color change was recorded using shade guides (Vita Classical and Vita Bleachedguide) and the Easyshade spectrophotometer at baseline, weekly and 30 days after the end of the bleaching. The risk and intensity of TS were evaluated by the McNemar and Wilcoxon Signed Rank tests, respectively. Color change (ΔSGU and ΔE) were evaluated by the Mann-Whitney test and a paired t-test, respectively (α = 0.05). RESULTS: No difference in the TS and color change was observed (p > 0.05). CONCLUSIONS: The incorporation of potassium nitrate and sodium fluoride in 10% carbamide peroxide at-home bleaching gel tested in this study did not reduce the TS and did not affect color change (RBR-4M6YR2).

Eficacia de la arginina al 8% y nitrato potásico al 5% en el tratamiento de la hipersensibilidad dentinaria: ensayo clínico aleatorio / Efficacy of 8% arginine and 5% potassium nitrate in dentin hypersensitivity therapy: a randomized clinical trial

RESUMEN: Objetivo: Comparar la eficacia clínica de dentífricos en base a arginina al 8%/ monofluorfosfato de sodio 1450 ppm versus nitrato de potasio al 5%/fluoruro de sodio 2500 ppm en la terapia de la hipersensibilidad dentinaria (HSD). Materiales y método: Ensayo clínico, aleatorio, controlado, doble ciego, de grupos paralelos. Treinta y cuatro voluntarios de 18 a 70 años, con HSD en escala Visual Análoga (EVA) ≥4 en 2 ó más dientes no molares, fueron distribuidos aleatoriamente en 2 grupos: grupo T1 (n=16): dentífrico de Arginina al 8%/ monofluorfosfato de sodio 1450 ppm; y grupo T2 (n=18): dentífrico de nitrato de Potasio al 5%/fluoruro de sodio 2500 ppm. Se evaluó HSD en EVA con estímulos evaporativos y térmicos, y se compararon sus valores, así como el grado promedio de HSD y su reducción (∆HSD), intra e intergrupal, al inicio y a las 4 semanas de tratamiento. Resultados: Ambos dentífricos disminuyeron el grado promedio de HSD entre el inicio y las 4 semanas de tratamiento (T1: 5.03 ± 1.23 versus 2.60 ± 1.27, p<0.05; T2: 4.73 ± 1.51 versus 2.71 ± 1.17, p<0.05). No hubo diferencias estadísticamente significativas entre ambos dentífricos al comparar el grado promedio de reducción de HSD durante la terapia (∆HSD T1: -2.43 ± 1.22 versus ∆HSD T2: -2.27 ± 1.42). Los datos fueron analizados en Stata versión 11. Conclusiones: Ambos dentífricos fueron clínicamente eficaces en reducir la HSD a las 4 semanas, sin existir diferencias estadísticamente significativas entre ambos.

ABSTRACT: Aim: To compare the clinical efficacy of 8% arginine/1450ppm sodium monofluorophosphate and 5% potassium nitrate/2500 ppm sodium fluoride dentifrices in the treatment of dentin hypersensitivity (DH). Methods: Parallel-design, double-masked, randomized controlled clinical trial. Thirty four volunteers aged 18 to 70 years, with DH and a visual analog scale (VAS) score ≥4 at least in two or more non-molar teeth, were randomized in two groups: T1 (n=16): 8% arginine/1450 ppm sodium monofluorophosphate dentifrice; and T2 (n=18): 5% potassium nitrate/2500 ppm sodium fluoride dentifrice. DH was assessed with evaporative and thermal stimuli; and their VAS measurements, mean DH value and DH reduction (∆DH) were compared, inside and between the groups at baseline and 4-week follow-up. Data were analysed through Stata® V11 program. Results: Both toothpastes decreased mean DH value between baseline and 4 weeks (T1: 5.03 ± 1.23 versus 2.60 ± 1.27, p<0.05; T2: 4.73 ± 1.51 versus 2.71 ± 1.17, p<0.05). There were no statistical differences between both dentifrices in mean DH reduction values during therapy (∆HSD T1: -2.43 ± 1.22 versus ∆HSD T2:-2.27 ± 1.42). Conclusions: Both dentifrices had clinical efficacy in decreasing DH in a 4- week therapy, without statistical differences between both of them.

Absence seizure associated with coloprep consumption in colonoscopy / Convulsão de ausência com o uso de Coloprep em colonoscopia

Coloprep is a bowel preparatory solution given before endoscopic procedures to get a unobscured internal vision. It has among its constituent's sodium sulphate, potassium sulphate and magnesium sulphate which produce an osmotic effect in the bowel. However, the use of such agents in hyponatremic and patients predisposed to seizures can have adverse ramifications. The current case outlines manifestation of absence seizure in a 52-year-old male patient who was administered Coloprep for colonoscopy. There was absence of other predisposing factors and the symptoms were ameliorated using timely identification and rectification of the underlying derangements.

Coloprep é uma solução preparatória intestinal administrada antes de procedimentos endoscópicos, com o objetivo de se ter uma visão interna não obscurecida. Entre os constituintes de Coloprep, observa-se sulfato de sódio, sulfato de potássio e sulfato de magnésio, que provocam efeito osmótico no intestino. Mas o uso de tais agentes em pacientes hiponatrêmicos e com predisposição para convulsões pode ter ramificações adversas. O caso em tela delineia uma manifestação de convulsão de ausência em paciente do gênero masculino com 52 anos e que recebeu Coloprep para colonoscopia. Não havia outros fatores predisponentes e os sintomas melhoraram graças à oportuna identificação e correção dos transtornos subjacentes.

Efficacy of tooth bleaching with the prior application of a desensitizing agent.

AIM: In the present study, we evaluated the efficacy of bleaching on enamel and opposite dentin surfaces using 35% hydrogen peroxide (HP) with the prior application of a desensitizing agent. METHODS: Thirty bovine dental fragments, with thicknesses of 1 mm enamel and 1.75 mm dentin, were stained in a solution of black tea. The fragments were randomly divided into three groups (n = 10) according to the following protocols: (a) 2% neutral fluoride + bleaching; (b) desensitizing agent + bleaching; and (c) without desensitizer + bleaching. The bleaching efficacy was evaluated four times: after staining with tea (baseline) and after each of the 3 weeks of bleaching, by means of the CIE Lab method using a reflectance spectrophotometer. The data coordinate L* was evaluated by an analysis of repeated measures with PROC MIXED and Tukey-Kramer's test. The ΔE values were subjected to anova and Tukey's test (α = 0.05). RESULTS: The 35% HP treatment showed greater efficacy on deep dentin after removal of the enamel stains, with increasing means during all times in all treatments. CONCLUSION: The use of a desensitizing agent prior to the bleaching session did not affect the mechanism of action of 35% HP with regard to tooth depth.

A prospective, open, comparative study of 5% potassium hydroxide solution versus cryotherapy in the treatment of genital warts in men.

BACKGROUND: Genital warts are caused by human papillomavirus infection and represent one of the most common sexually transmitted diseases. Many infections are transient but the virus may recur, persist, or become latent. To date, there is no effective antiviral treatment to eliminate HPV infection and most therapies are aimed at the destruction of visible lesions. Potassium hydroxide is a strong alkali that has been shown to be safe and effective for the treatment of genital warts and molluscum contagiosum. Cryotherapy is considered one of the most established treatments for genital warts. No comparative trials have been reported to date on the use of potassium hydroxide for genital warts. OBJECTIVE: A prospective, open-label, randomized clinical trial was conducted to compare topical potassium hydroxide versus cryotherapy in the treatment of genital warts affecting immunocompetent, sexually active men. METHODS: Over a period of 10 months, 48 patients were enrolled. They were randomly divided into two groups and selected on an alternative basis for either potassium hydroxide therapy or cryotherapy. While response to therapy did not differ substantially between both treatment modalities, side effects such as local pain and post-treatment hypopigmentation were considerably more prevalent in the groups treated using cryotherapy. RESULT: In our study, potassium hydroxide therapy proved to be at least as effective as cryotherapy and offered the benefit of a better safety profile. CONCLUSION: Topical 5% potassium hydroxide presents an effective, safe, and low-cost treatment modality for genital warts in men and should be included in the spectrum of therapies for genital warts.

A prospective, open, comparative study of 5% potassium hydroxide solution versus cryotherapy in the treatment of genital warts in men

BACKGROUND: Genital warts are caused by human papillomavirus infection and represent one of the most common sexually transmitted diseases. Many infections are transient but the virus may recur, persist, or become latent. To date, there is no effective antiviral treatment to eliminate HPV infection and most therapies are aimed at the destruction of visible lesions. Potassium hydroxide is a strong alkali that has been shown to be safe and effective for the treatment of genital warts and molluscum contagiosum. Cryotherapy is considered one of the most established treatments for genital warts. No comparative trials have been reported to date on the use of potassium hydroxide for genital warts. OBJECTIVE: A prospective, open-label, randomized clinical trial was conducted to compare topical potassium hydroxide versus cryotherapy in the treatment of genital warts affecting immunocompetent, sexually active men. METHODS: Over a period of 10 months, 48 patients were enrolled. They were randomly divided into two groups and selected on an alternative basis for either potassium hydroxide therapy or cryotherapy. While response to therapy did not differ substantially between both treatment modalities, side effects such as local pain and post-treatment hypopigmentation were considerably more prevalent in the groups treated using cryotherapy. Result: In our study, potassium hydroxide therapy proved to be at least as effective as cryotherapy and offered the benefit of a better safety profile. CONCLUSION: Topical 5% potassium hydroxide presents an effective, safe, and low-cost treatment modality for genital warts in men and should be included in the spectrum of therapies for genital warts. .

The influence of desensitizing dentifrices on pain induced by in-office bleaching.

The purpose of this study was to evaluate whether the use of desensitizing dentifrices used 15 days prior to and after in-office tooth bleaching could eliminate or reduce tooth sensitivity. After institutional review board approval and informed consent, 45 subjects were selected and divided into 3 groups according to the dentifrice selected: Colgate Total (CT), Colgate Sensitive Pro-Relief (CS) or Sensodyne ProNamel (SP). The subjects used toothpaste and a toothbrush provided to them for 15 days prior to bleaching. They were then submitted to two in-office bleaching sessions (Whiteness HP Blue Calcium). Their tooth sensitivity was assessed using the Visual Analog Scale (VAS) for a week after each session. Their tooth shade alteration was measured with a Vitapan Classical shade guide to determine if the dentifrices could influence the effectiveness of the bleaching agent. The data were submitted to Wilcoxon, Kruskal-Wallis and Mann-Whitney tests (α = 0.05). The use of desensitizing dentifrices did not affect the bleaching efficacy. In regard to tooth sensitivity, there was a statistically significant difference between the results of the Control Group and Group T2 after the first session (p = 0.048). There was no statistically significant difference in the results for the other groups after the first session. In regard to the second session, there was no statistically significant difference in the results for all the groups. The use of a desensitizing dentifrice containing nitrate potassium reduced tooth sensitivity during the bleaching regimen. Dentifrices containing arginine and calcium carbonate did not reduce tooth sensitivity. Color change was not influenced by the dentifrices used.

The influence of desensitizing dentifrices on pain induced by in-office bleaching

The purpose of this study was to evaluate whether the use of desensitizing dentifrices used 15 days prior to and after in-office tooth bleaching could eliminate or reduce tooth sensitivity. After institutional review board approval and informed consent, 45 subjects were selected and divided into 3 groups according to the dentifrice selected: Colgate Total (CT), Colgate Sensitive Pro-Relief (CS) or Sensodyne ProNamel (SP). The subjects used toothpaste and a toothbrush provided to them for 15 days prior to bleaching. They were then submitted to two in-office bleaching sessions (Whiteness HP Blue Calcium). Their tooth sensitivity was assessed using the Visual Analog Scale (VAS) for a week after each session. Their tooth shade alteration was measured with a Vitapan Classical shade guide to determine if the dentifrices could influence the effectiveness of the bleaching agent. The data were submitted to Wilcoxon, Kruskal-Wallis and Mann-Whitney tests (α = 0.05). The use of desensitizing dentifrices did not affect the bleaching efficacy. In regard to tooth sensitivity, there was a statistically significant difference between the results of the Control Group and Group T2 after the first session (p = 0.048). There was no statistically significant difference in the results for the other groups after the first session. In regard to the second session, there was no statistically significant difference in the results for all the groups. The use of a desensitizing dentifrice containing nitrate potassium reduced tooth sensitivity during the bleaching regimen. Dentifrices containing arginine and calcium carbonate did not reduce tooth sensitivity. Color change was not influenced by the dentifrices used.

Eccrine porocarcinoma with carcinomatous lymphangitis in a patient with history of arsenic exposure: a case report.

Eccrine porocarcinoma is a potentially fatal form of sweat gland carcinoma, due to its propensity to metastasize through lymph vessels. The authors report the case of a 69-year-old female who presented with swelling of the right leg and an ulcerated lesion of the right great toe. The initial histologic diagnosis was invasive squamous cell carcinoma. On follow-up, the patient developed lymphangitic tumor spread in the right leg, associated with right inguinal lymphadenopathy and lesions in vulva and flank. Reevaluation of the toe lesion led to a revised diagnosis of eccrine porocarcinoma. The patient also had 2 basal cell carcinomas of the multicentric/superficial type in the skin overlying the left breast. Past history included chronic ingestion of liquore arsenic (Fowler's solution) in early adulthood as treatment for dermatitis herpetiformis.

Assessment of tooth sensitivity using a desensitizer before light-activated bleaching.

UNLABELLED: CLINICAL OBJECTIVE: This clinical study evaluated whether the use of a desensitizing agent (5% potassium nitrate/2% sodium fluoride) before in-office light-activated bleaching decreased this sensitivity. METHODS: Before in-office bleaching with 35% hydrogen peroxide gel (three applications, 15 minutes each) associated with an LED/laser unit, clinicians applied a placebo gel or the desensitizing agent on the buccal surfaces of all participants. They repeated this protocol one week later. Patients recorded their tooth sensitivity on a 0-to-4 scale. The authors used one-way repeated measures ANOVA to compare the tooth color changes and non-parametric statistics to compare the different percentages of patients with tooth sensitivity and the levels of tooth sensitivity in the different periods of time between groups (α=0.05). RESULTS: The use of a desensitizing gel did not affect the bleaching efficacy. Eighty percent and 100% of the participants from the experimental and placebo groups, respectively, experienced tooth sensitivity (p>0.05). The intensity of sensitivity was similar immediately after bleaching for both groups (p>0.05). After 24 hours, lower sensitivity was reported in the experimental group, while most of the participants from the placebo group experienced tooth sensitivity (p<0.05).

INCAP studies of endemic goiter and its prevention.

The high prevalence of goiter among adults in its member countries of Central America and Panama was observed as soon as INCAP began field studies. This led to systematic studies of goiter in schoolchildren in all of the countries as described, beginning with Guatemala where the rate was 38% nationally. However, efforts to eliminate the consequences of iodine with iodized salt using the water soluble potassium iodate and a process that had proved successful in Switzerland and the United States could not be used with the crude moist salt of the region. INCAP identified potassium iodate that is insoluble in water, and in four schools (two each in El Salvador and Guatemala) proved that the iodine in this compound was as available as that in potassium iodate. It remained evenly distributed in moist salt. When added to salt in Guatemala, goiter rate dropped to 15% in four years and less than 5% in eight years. Compulsory iodation of salt in other developing countries followed with comparable results. This method is now used in worldwide campaigns against iodine deficiency in developing countries.

Preventive effect of commercial desensitizing toothpastes on bovine enamel erosion in vitro.

This study evaluated in vitro commercial desensitizing toothpastes with respect to the prevention of erosion and explored the effect of their agents alone or in combination with fluoride. Bovine enamel blocks were randomly allocated to five groups of 20 and exposed to: Sensodyne ProNamel (1,425 ppm F as NaF, 5% KNO(3)), Sensodyne Original (no fluoride, 10% SrCl(2)), Colgate Sensitive (1,450 ppm F as sodium monofluorophosphate, 5% K citrate), Crest (fluoride-only toothpaste, 1,100 ppm F as NaF) and water (negative control). A second experiment was conducted with experimental dentifrices containing fluoride (NaF, 1,100 ppm F), 10% SrCl(2), 5% KNO(3 )or 5% K citrate alone or the latter three combined with F. The samples were submitted to four cycles, alternating demineralization (cola, 10 min) and remineralization (artificial saliva, 1 h). Before and between cyclic de- and remineralization, blocks were treated with slurries of the respective toothpastes or water (1 min). Erosive tissue loss was analyzed by profilometry. Data were analyzed by Kruskal-Wallis and Dunn's tests (p < 0.05). The mean erosion depth (+/- SE, mum) was significantly less for Colgate Sensitive (0.04 +/- 0.00), Sensodyne Original (0.06 +/- 0.01) and Crest (0.07 +/- 0.01) than for Sensodyne ProNamel (2.36 +/- 0.25) or water (2.92 +/- 0.24), which did not significantly differ from each other. Both F and the desensitizing agents alone reduced erosion, but no additive effect was found. In addition, the combination of F and KNO(3) did not reduce erosion. These in vitro results suggest that the presence of fluoride or desensitizing substances in toothpastes, alone or in combination, can reduce erosion of enamel, but this is not valid for all the formulations.

Influence of desensitizing agents on the microshear bond strength of adhesive systems to dentin.

The aim of this study was to evaluate the effect of desensitizing agents on the micro-shear bond strength of adhesive systems to dentin. Forty bovine teeth were divided into 8 groups (n=5): G1--Single Bond (SB); G2--GH.F + SB; G3-- Desensibilize + SB; G4--essensiv + SB; G5 --ingle Bond 2 (SB2); G6--H.E + SB2; G7--esensibilize + SB2; G8--Dessensiv + SB2. In all of the groups, the desensitizing agents were applied after phosphoric acid etching and before the dentin adhesive application. Z250 composite resin tubes were bonded on the treated surface. After 24 hours, the teeth were tested in a universal machine. Data were submitted to ANOVA and Tukey's test (5%). The results showed that the groups where Desensibilize and Dessensiv were applied exhibited smaller bond strength values.

A scanning electronic microscopy study of the action of different desensitizing agents on bovine dentin.

This study sought to use scanning electronic microscopy (SEM) to evaluate the dentinal tubule occlusion potential of different desensitizing agents. Ten slices of bovine dentin were divided into six fragments, cleaned (using ultrasound), and etched for 15 seconds with a 35% phosphoric acid solution. All but one of the groups received a different desensitizing agent; the sixth group served as a control and received no additional treatment. After the agents were applied, the dentin specimens were analyzed by SEM and scores were assigned based on the extent of tubular obliteration. Only three agents demonstrated tubular sealing that was significantly different from that of the control group.

Evaluation of the effectiveness of laser fluorescence in monitoring in vitro remineralization of incipient caries lesions in primary teeth.

The purpose of this investigation was to examine the effectiveness of laser fluorescence for monitoring in vitro remineralization of caries lesions. Seventeen natural enamel lesions in primary molars were each cut into two parts. One part was exposed, at room temperature, to a remineralizing solution (experimental) and the other part to water (control) for 28 days. Laser fluorescence readings were taken at the beginning of the experiment and during the experiment. At the end of the experiment, lesion depth in the experimental halves was significantly less than in the control halves (p < 0.01), suggesting that remineralization had occurred. However, the laser fluorescence readings showed no statistically significant changes during the experiment, either in the experimental or control halves. We conclude that laser fluorescence was not able to detect in vitro remineralization of natural incipient caries lesions of primary teeth.