Color and surface roughness alterations of bulk-fill resin composites submitted to simulated toothbrushing with whitening dentifrices

Aim: To evaluate the surface roughness and color stability of bulk-fill resin composites after simulated toothbrushing with whitening dentifrices. The radioactive/relative dentin abrasion (RDA) and radioactive/relative enamel abrasion (REA) of dentifrices were also assessed. Methods: Specimens (n=10) of Tetric N Ceram Bulk Fill (TNCB), Filtek One Bulk Fill (FOB) resin composites, and Z100(Control) were prepared using a cylindrical Teflon matrix. Surface roughness (Ra, µm) was assessed by a roughness meter and the color evaluations (ΔEab , ΔE00 , WID ) were performed using a digital spectrophotometer based on the CIELAB system. Three measurements were performed per sample, before and after simulated toothbrushing with 3D Oral-B White Perfection (3DW) and Black is White (BW) dentifrices. The abrasivity (REA and RDA values) of the used dentifrices was also determined by the Hefferren abrasivity test. Results: The Ra values increased significantly in all resin composites after 3DW and BW toothbrushing. The acceptable threshold color varied among resin composites, and TNCB and Z100 presented the highest ΔEab and ΔE00 for BW dentifrice. The 3DW dentifrice was significantly more abrasive than BW dentifrice on enamel and dentin. Conclusions: simulated toothbrushing with tested whitening dentifrices increased the surface roughness at acceptable levels. The Tetric N Ceram Bulk-fill and Z100 composite showed the highest color alteration in BW. 3D White Perfection dentifrice was more abrasive on dentin and enamel than Black is White.

Effects of black tea tooth staining previously to 35% hydrogen peroxide bleaching

Aim: To determine if the artificial staining with black tea (BT) influences the enamel microhardness before in-office bleaching and if BT staining is necessary to evaluate the efficacy of bleaching with 35% hydrogen peroxide Methods: Enamel/dentin blocks were randomized into groups according to the staining protocol (n=5/group): (CO) control ­ maintained in artificial saliva solution (AS); (BT4) immersed in black tea solution for 4 h; (BT24) immersed in black tea solution for 24 h. After the staining protocols, all specimens were kept in AS for one week, followed by bleaching (three sessions of HP application for 40 min). Knoop surface microhardness (kgF/mm2) was determined at baseline (T0), after staining (T1), after 7 days of storage in AS (T2), and after bleaching (T3). The color (∆E00) and coordinate changes (∆L, ∆a, ∆b) were measured using a digital spectrophotometer at T0 and T3. Data were submitted to one-way (∆E00, ∆L, ∆a, ∆b) or two-way ANOVA repeated measures (kgF/mm2) and Tukey's test (a=5%). Results: The staining protocols (BT4 and BT24) promoted significantly lower microhardness (T1 and T2, p<0.05) than CO, whereas CO was the only group to maintain microhardness values over time. Bleaching promoted perceptible ∆E00 without a significant difference among the groups regardless of the staining protocol (p=0.122). CO and BT4 showed no differences in terms of ∆L and ∆a (p>0.05), but BT4 displayed a higher ∆b than CO. Conclusion:The artificial staining with BT negatively affected the enamel surface microhardness and was not essential to evaluate the efficacy of 35% hydrogen peroxide bleaching

The influence of the CIELAB parameters on the perception of color after the use of whitening toothpastes

Aim: To evaluate the influence of the parameters L* a* b* on the variation of the color of bovine tooth enamel submitted to artificial darkening, after simulated brushing, with whitening toothpastes containing blue covarine. Methods: To undertake this study in vitro, 60 specimens (SP) were divided into 6 groups (n=10): control group (CGwater) and 5 test groups (GT1-Colgate Total 12, GT2-Oral-B 3D White Perfection, GT3- Colgate Luminous Instant White, GT4-CloseUp White Diamond Attraction, GT5-Sorriso Xtreme White). The specimens were darkened with coffee and submitted to simulated brushing for 6, 12, and 24 months. The alteration in the color was evaluated using CIELAB parameters and the ΔL, Δa, Δb and ΔE were calculated. The data was analyzed through generalized linear models using the R program and considering a level of significance of 5%. Results: The parameters L*, a* and the ΔL, Δa obtained better results in the test group than in the control group. There were no statistical differences between CG and the test groups for the evaluation of the b* parameter. In the evaluation of the Δb, the GT3 differed statistically from the CG. In relation to the ΔE, all the group tests showed a variation in color statistically greater than that of the CG and the GT4 showed the greatest variation, not differing from the GT3 during the periods studied. Conclusion: The mechanical and optical whitening agents positively influenced the values L*a* and b*, as well as in its variations and in the ΔE. It is important to emphasize, however, that to analyze tooth whitening it is necessary to evaluate their parameters together

Eficácia e segurança do enxaguatório clareador sobre o esmalte dental: estudo clínico controlado randomizado e estudo in vitro / Efficacy and safety of whitening mouthrinse on enamel: randomized clinical trial and in vitro study

Enxaguatórios clareadores tornaram-se muito populares devido ao seu fácil uso e disponibilidade. Contudo, não há evidência dos efeitos e segurança desses produtos sobre o esmalte sadio e desmineralizado. Esta proposta foi dividida em duas partes. A primeira foi um estudo clínico randomizado que avaliou a eficácia e segurança do enxaguatório clareador. Participantes (n=45) foram alocados aleatoriamente em três grupos de tratamento: LWE (Listerine Whitening Extreme­peróxido de hidrogênio a 2,5%); PL (Enxaguatório placebo); e OPF (Opalescence PF­peróxido de carbamida a 10%). O tratamento foi realizado 1x/dia por 14 dias durante 2h para OPF, e 2x/dia por 90 dias durante 30s para LWE e PL. A cor dos dentes foi avaliada com escalas de cor (DUEC) e por espectrofotometria. Foram avaliados sensibilidade dental, condição gengival, potencial de desmineralização do esmalte, e a satisfação do participante. As avaliações foram realizadas em diferentes tempos. Para as escalas de cor, KruskalWallis mostrou diferença significante entre os tratamentos nos tempos avaliados (p<0,05). LWE apresentou maiores valores de DUEC comparado ao PL a partir de 60 dias. PL e OPF exibiram valores constantes, sendo significativamente maiores para OPF. Para o espectrofotômetro, RM-ANOVA mostrou diferença significante para os grupos e interação (p<0,05). LWE apresentou maiores valores de alteração de cor do que PL a partir de T14. OPF exibiu os maiores valores de alteração de cor durante todo o período de estudo. Após 2 anos, houve manutenção da cor dos dentes para todos os grupos. Houve baixa intensidade de sensibilidade para LWE e OPF. Nenhum participante apresentou inflamação gengival. LWE e OPF promoveram uma diminuição significativa na concentração de cálcio, mas após 1 semana, os valores foram intermediários. A concentração de fosforo não apresentou alteração nos tempos avaliados. Todos os participantes ficaram satisfeitos com o tratamento com OPF e 67% dos participantes do grupo LWE apresentaram satisfação. A segunda parte consistiu em um estudo in vitro que comparou o efeito do enxaguatório clareador na desmineralização do esmalte e em lesões incipientes de cárie durante ciclagem de pH. Espécimes de esmalte/dentina bovino (n=120) com a superfície dividida em três áreas [esmalte sadio controle, esmalte tratado (ET); e lesão incipiente de carie tratada (LICT)] foram distribuídos aleatoriamente nos grupos experimentais: LWE; PL; OPF e água deionizada (AD). Os tratamentos (2min para LWE, PL e AD; e 2h para OPF) foram realizados durante uma ciclagem de pH de 28 dias (6´60min desmineralização). Intensidade de reflexão superficial (rSRI), perda mineral e concentração de flúor (espécimes adicionais) foram avaliados. Para ET, foi observado maior valor de rSRI em LWE (89,99%±6,94) e maior diminuição de rSRI foi observada para OPF e AD. Não houve perda mineral nos grupos (p>0,05). Para LICT, rSRI diminuiu significativamente após a ciclagem para todos os grupos sem diferença entre eles (p>0,05). Maior concentração de flúor foi encontrada em OPF. LWE e OPF exibiram efeitos semelhantes na perda mineral com valores intermediários. Houve eficácia clareadora tanto para LWE quanto para OPF e manutenção da cor após 2 anos. Houve efeito protetor do enxaguatório durante a ciclagem. (AU)

Whitening mouthrinses have become very popular because they are easy to use and are accessible. However, there is no evidence of the effects and safety of this product on sound and demineralized enamel. The proposal comprised in two parts. The first one was a randomized clinical trial that evaluated the efficacy and safety of the whitening mouthrinse. Participants (n=45) were randomly allocated to three treatment groups: LWE (Listerine Whitening Extreme­2.5% hydrogen peroxide); PL (placebo mouthrinse); and OPF (Opalescence PF­10% carbamide peroxide). The treatment was performed 1x/day for 14 days during 2h for OPF, and 2x/day for 90 days during 30s for LWE and PL. Tooth color was measured using shade guides (DUEC) and spectrophotometer. Tooth sensitivity, gingival condition, enamel demineralization potential, and participant satisfaction were analyzed. The analyses were performed in different times. For shade guides, Kruskal-Wallis showed a significant difference between treatments in the evaluated times (p<0.05). LWE showed higher DUEC values compared to PL after 60 days. PL and OPF exhibit constant values, being significantly higher for OPF. For spectrophotometer, RM-ANOVA showed significance for the groups and interaction (p<0.05). LWE showed higher color difference values than PL from T14. OPF exhibited the highest values throughout the study. After 2 years, there was maintenance of tooth color for all groups. There was lower intensity of sensitivity for LWE and OPF. No participant exhibited gingival inflammation. LWE and OPF promote a significant decrease in calcium concentration, but after 1 week the values were intermediate. Phosphorus concentration did not alter over time. All participants of OPF group were satisfied with the treatment and 67% of the participants of LWE group showed satisfaction. The second part of the study consisted of an in vitro study that compared the effect of whitening mouthrinse on enamel demineralization and on initial caries lesions. Bovine enamel/dentin specimens (n=120) had their surface divided into three areas [control sound enamel, enamel treated (ET); and initial caries lesion treated (ICLT)] and were randomly assigned to the experimental groups: LWE; PL; OPF; and deionized water (DW). The treatments (2min for LWE, PL and DW; and 2h for OPF) were performed during a 28-day pH cycle (6x60min demineralization). Surface reflection intensity (rSRI), mineral loss, and fluoride concentration (additional specimens) were performed. For ET, a higher value of rSRI was observed in LWE (89.99%±6.94) and a greater decrease in rSRI was observed for OPF and DW. There was no mineral loss in the groups (p>0.05). For ICLT, rSRI was significantly significant after cycling for all groups with no difference between them (p>0.05). Higher fluoride concentration was found in OPF. LWE and OPF exhibited similar effects on the mineral loss with intermediate values. There was whitening efficacy for both LWE and OPF and color maintenance after 2 years. There was a protective effect of the mouthrinse during cycling (AU)

Cecropia pachystachya Trécul: a promising ingredient for skin-whitening cosmetics

Abstract Because it promotes the lightening of pigment spots, tyrosinase inhibition is one of the mechanisms of depigmenting cosmetic products. Considering the adverse effects produced by synthetic depigmenting actives, the search for new therapeutic options is desirable, and plant extracts are possible candidates for hyperpigmentation treatment. Glycolic extracts of Cecropia pachystachya Trécul are, therefore, the focus of this study. Its chemical characterization, antioxidant activity, tyrosinase inhibition, and cell viability were evaluated. Glycolic extracts were obtained by macerating the leaves of C. pachystachya in grain alcohol and glycerin or propylene glycol. Both had a similar chemical constitution, the glycerin being more efficient in concentrating phenolic compounds and flavonoids. Analyses by UHPLC-MS detected quinic acid, chlorogenic acid isomers, proanthocyanidin dimers type B and C, catechin/epicatechin, orientin/isoorientin, isoorientin 2"-O-xyloside, vitexin/isovitexin, and rutin. 5-O-caffeoylquinic acid was then quantified was then quantified, with predominance in the extract produced with propylene glycol. These extracts showed a high antioxidant capacity by the method of DPPH, ß-carotene, and nitric oxide. As for depigmenting activity, both extracts were able to inhibit tyrosinase. Cell viability assay also revealed that the extracts could safely be used in concentrations of ≤ 125 µg/mL. Thus, this study demonstrated for the first time that the glycolic extracts of C. pachystachya have promising chemical and biological characteristics for the development of a multifunctional cosmetic with antioxidant and tyrosinase-inhibition activities

Efectividad de sustancias químicas en el clareamiento y biopelícula dental aplicado en el consultorio y ambulatorio / Effectiveness of chemical substances in bleaching and dental biofilm applied in the office and outpatient

El blanqueamiento dental está considerado como pieza fundamental en el embellecimiento de los seres humanos, ya que permite la restauración de la "sonrisa perfecta". Este proceso en sí, es poco invasivo y juega como un gran papel como aliado en la restauración satisfactoria de la sonrisa y autoestima del paciente. Es un procedimiento que debe ser aplicado cuidadosamente para lograr los efectos positivos del mismo. El fundamento de esta técnica es aclarar la tonalidad que han sufrido los dientes por diversos factores: extrinsecos, intrínsecos y decoloraciones internas. Durante el procedimiento, es usual el uso de peróxido de hidrógeno (H2O2) en concentraciones que van del 10 al 32 % en volumen o el peróxido de carbamida, un compuesto conformado por peróxido de hidrógeno y urea concentraciones del 10 al 22 %. El uso de peróxido de hidrógeno se lleva a cabo fundamentalmente en los consultorios, mientras que el uso del peróxido de carbamida es un procedimiento doméstico. A pesar de los excelentes resultados que se obtiene al usar ambos blanqueadores, su uso puede ocasionar erosiones dentales y sensibilidad dentaria. El primer caso, puede llevar a la adherencia de bacterias cariogénicas como el Strepctococus mutans responsable de caries. Los resultados obtenidos, demostraron que el peróxido de hidrógeno es un agente más agresivo que el peróxido de carbamida, lo cual origina mayor sensibilidad dentaria y un mayor control bacteriano; en cambio el peróxido de carbamida fue mejor blanqueador y originó menor sensibilidad dental(AU)

Tooth whitening is considered a fundamental piece in the beautification of human beings, since it allows the restoration of the "perfect smile". This process itself is minimally invasive and plays a great role as an ally in the satisfactory restoration of the patient's smile and self-esteem. It is a procedure that must be carefully applied to achieve its positive effects. The basis of this technique is to clarify the shade that the teeth have suffered due to various factors: extrinsic, intrinsic and internal discoloration. During the procedure, the use of hydrogen peroxide (H2O2) in concentrations ranging from 10 to 32% by volume or carbamide peroxide, a compound made up of hydrogen peroxide and urea concentrations of 10 to 22%, is usual. The use of hydrogen peroxide is mainly carried out in offices, while the use of carbamide peroxide is a home procedure. Despite the excellent results obtained by using both whiteners, their use can cause dental erosion and tooth sensitivity. The first case can lead to the adherence of cariogenic bacteria such as Streptococcus mutans responsible for caries. The results obtained showed that hydrogen peroxide is a more aggressive agent than carbamide peroxide, which causes greater dental sensitivity and greater bacterial control; On the other hand, carbamide peroxide was a better whitener and caused less dental sensitivity(AU)

Assessment of a novel bleaching agent formula containing 35% hydrogen peroxide and titanium tetrafluoride: an in vitro study

Abstract: This study developed experimental gels containing titanium tetrafluoride (TiF4) combined with commercial 35% hydrogen peroxide (HP), and evaluated bleaching efficacy and pH of the gels, and mineral content and morphology of enamel submitted to these treatments. In phase-1, different stock gels mixed with TiF4 were combined with HP. In phase-2, the selected gels were tested on enamel/dentin specimens (n=8): HP; HP and Natrosol+TiF4 (HPnT); HP and Natrosol+Chemygel+TiF4 (HPncT); HP and Aristoflex+TiF4 (HPaT). Bleaching was performed in four sessions (3x15min-application/session). Color (CIEL*a*b*) and whiteness index (WID) were measured after each session, whereas whiteness index differences (ΔWID), color alteration (CIELab-ΔE, CIEDE2000-ΔE00), enamel morphology and pH, at end of bleaching therapy. The change in Knoop microhardness (ΔKHN) was compared before and after bleaching. Data were analyzed by two-way repeated measures ANOVA and Bonferroni (CIEL*, a*, b*), one-way ANOVA and Tukey (ΔWID, ΔE, ΔE00), and LSD (ΔKHN) tests (α=5%). SEM and pH measurements were submitted to descriptive analysis. No differences were observed in lightness (L*) or WID among the groups (p > 0.05), but HP exhibited lower b* values (p<0.05), higher ΔWID than HPnT, and the highest ΔE among the groups (p < 0.05). No differences in ΔE00 were observed between HP and HPncT (p > 0.05), and HPncT showed higher ΔKHN than HP (p < 0.05). HP presented pH values closer to neutral (6.9), whereas experimental agents showed acidic pH values (2.3-3.9). No morphological changes were observed in HP or HPncT groups. HPncT was able to bleach the enamel and maintain enamel microhardness and surface integrity, even at low pH.

Initial and pulp chamber concentration of hydrogen peroxide using different bleaching products / Concentração de peróxido de hidrogênio na câmara pulpar utilizando diferentes produtos clareadores

Objective: This study's aim was to quantify the hydrogen peroxide (HP) penetration into the pulp chamber of teeth submitted to different protocols of bleaching. Material and Methods: Ninety premolars were randomly divided into nine groups according to the bleaching agent protocol (n = 10): control (no bleaching), carbamide peroxide 10% [10% CP], carbamide peroxide 16% [16% CP], carbamide peroxide 22% [22% CP], hydrogen peroxide 4% [4% HP], hydrogen peroxide 6% [6% HP], hydrogen peroxide 7.5% [7.5% HP], hydrogen peroxide 10% [10% HP] and hydrogen peroxide 35% [35% HP]. The penetration of HP was measured via spectrophotometric analysis of the acetate buffer solution from the pulp chamber. The absorbance of the resulting solution was determined in a spectrophotometer and converted into equivalent concentration of HP (µg/ mL). To analyze the concentration of HP, the titration of bleaching agents with potassium permanganate was used. Data were subjected to ANOVA and Tukey's test for pairwise comparison (α = 0.05). Results: Higher concentration of HP in the pulp chamber was found in the HP 35% group (p < 0.0001). No significant difference between at-home protocols were observed (p = 0.64). Titration values showed that the concentration of the products was similar to that claimed by the manufacturer. Conclusion: It follows that the amount of HP that reaches the pulp chamber is not proportional to the concentration of whitening gels, but depends on the application time recommended by the manufacturers (AU)

Objetivo: o objetivo deste estudo foi quantificar a penetração do peróxido de hidrogênio (PH) na câmara pulpar dos dentes submetidos a diferentes protocolos de clareamento. Material e Métodos: Noventa pré-molares foram divididos aleatoriamente em nove grupos, de acordo com o protocolo do agente clareador (n = 10): controle (sem clareamento), peróxido de carbamida 10% [PC 10%], peróxido de carbamida 16% [PC 16%], peróxido de carbamida 22% [PC 22%], peróxido de hidrogênio 4% [PH 4%], peróxido de hidrogênio 6% [PH 6%], peróxido de hidrogênio 7,5% [PH 7,5%], peróxido de hidrogênio 10% [PH 10%] e peróxido de hidrogênio 35% [PH 35%]. A penetração de PH foi medida por análise espectrofotométrica da solução de tampão de acetato da câmara pulpar. A absorvância da solução resultante foi determinada em um espectrofotômetro e convertida em concentração equivalente de PH (µg / mL). Para analisar a concentração de PH, foi utilizada a titulação de agentes clareadores com permanganato de potássio. Os dados foram submetidos à ANOVA e teste de Tukey para comparação pareada (α = 0,05). Resultados: Foi encontrada maior concentração de PH na câmara pulpar no grupo PH 35% (p < 0,0001). Não foi observada diferença significativa entre os protocolos domiciliares (p = 0,64). Os valores de titulação mostraram que a concentração dos produtos era semelhante à reivindicada pelo fabricante. Conclusão: Conclui-se que a quantidade de PH que atinge a câmara pulpar não é proporcional à concentração de géis clareadores, porém depende do tempo de aplicação recomendado pelos fabricantes.(AU)

Efeitos do uso de produtos clareadores de autoaplicação sobre a superfície de uma resina composta nanoparticulada / The effects of over-the-counter bleaching products on the surface of nanofilled composite

Objetivo: Avaliar a alteração da rugosidade superficial de uma resina composta nanoparticulada (Filtek Z350 XT ® ) após o uso de produtos clareadores de autoaplicação contento baixa concentração de peróxido de hidrogênio. Métodos: Para isto, foram confeccionados 30 corpos de prova deste material, divididos aleatoriamente em 3 grupos com 10 amostras cada, da seguinte forma: G1 (grupo controle) no qual as amostras não foram submetidas à ação de nenhum produto clareador; G2, realização de procedimento clareador com peróxido de hidrogênio a 10% (Crest 3D White Professional Effects Whitestrips ® ) em 2 aplicações de 30 minutos, por 10 dias consecutivos; e G3, tratamento com peróxido de hidrogênio a 7,7% (pincel Pretty Smile ® ) com o mesmo número de aplicações, tempo e dias do G2. Após este período cada corpo de prova foi analisado no rugosímetro Surftest SJ-301, para determinar a sua rugosidade superficial média. Estes dados foram então submetidos à análise estatística por meio da análise de variância (ANOVA) e teste de Tukey, nível de significância de 5% para comparações múltiplas. Resultados: Ao final do experimento, houve diferenças estatísticas significantes entre o grupo controle (G1) e os demais grupos (G2 e G3), com p < 0,05. Porém, quando analisados apenas os grupos submetidos ao clareamento com o peróxido de hidrogênio em diferentes concentrações (G2 e G3), não foi encontrada diferença significativa (p > 0,05). Conclusão: Após 10 dias, os produtos clareadores testados determinaram aumento significativo nos valores de rugosidade superficial média da resina composta nanoparticulada.

Aim: Tod evaluate the change in surface roughness of a nanoparticulate composite resin (Filtek Z350 XT ® ) after using over-the-counter bleaching products, containing a low concentration of hydrogen peroxide. Methods: For this, 30 specimens of this material were made, randomly divided into 3 groups with 10 samples each, as follows: G1 (control group) in which the samples were not subjected to the action of any bleaching product; G2, performing a bleaching procedure with 10% hydrogen peroxide (Crest 3D White Professional Effects Whitestrips ® ), in 2 applications of 30 minutes, for 10 consecutive days; and G3, treatment with 7.7% hydrogen peroxide (Pretty Smile ® ), with the same number of applications, time, and days as G2. After this period, each specimen was analyzed, using the Surftest SJ-301, to determine its average surface roughness. These data were then subjected to statistical analysis through analysis of variance (ANOVA) and Tukey's Test, with a significance level of 5% for multiple comparisons. Results: Statistically significant differences were found between the control group (G1) and the other groups (G2 and G3), with p < 0.05. However, when analyzing only the groups submitted to bleaching agents with hydrogen peroxide in different concentrations (G2 and G3), no significant difference was found (p > 0.05). Conclusions: After 10 days, the bleaching products tested in this study determined a significant increase in the average surface roughness values of the nanoparticulate composite resin.

Titanium dioxide nanotubes incorporated into bleaching agents: physicochemical characterization and enamel color change

Abstract Titanium dioxide nanotubes are nanostructures that can accelerate the oxidation reaction of bleaching procedures and promote a more effective whitening effect. Objective This study evaluated physicochemical properties of bleaching agents incorporated with titanium dioxide (TiO2) nanotubes, and the effects on tooth color change at different periods. Methodology 40 premolars were treated according to the following groups (n=10): CP - 10% carbamide peroxide (1 hour daily/21 days); CPN - CP incorporated into TiO2; HP - 40% hydrogen peroxide (three 40-minute sessions/7 days apart); HPN - HP incorporated into TiO2. Color shade was evaluated at five different periods (baseline, after 7, 14 and 21 days of bleaching, and 7 days after end of treatment) according to Vita Classical, CIELab and CIEDE2000 scales. Mean particle size (P), polydispersity (PO) and zeta potential (ZP) were evaluated using dynamic light scattering. Data on the different variables were analyzed by mixed model tests for measures repeated in time (ZP e L*), generalized linear models for measures repeated in time (P, PO, Vita Classical and b*), and Friedman and Mann-Whitney tests (a* and color change/ΔE and ΔE00). Results CP and CPN presented higher P, higher PO and lower ZP than HP and HPN (p≤0.05). All groups showed a significant decrease in Vita Classical color scores after 7 days of bleaching (p<0.05), and HPN presented a greater significant reduction than the other groups. L* increased in TiO2 presence, in all groups, without any differences (p>0.05) in bleaching time. A significant reduction occurred in the a* and b* values for all the groups, and HPN presented lower a* and b* values (p<0.05) than CPN. ΔE was clinically noticeable after 7 days, in all groups, and all groups resulted in a perceptible color change according to ΔE00. Conclusion TiO2 did not influence physicochemical properties of the bleaching agents. HPN presented more effective tooth bleaching than CPN.

Decomposition rate, ph, and enamel color alteration of at-home and in-office bleaching agents

Abstract This study evaluated the decomposition rate (DR), pH, enamel color alteration (DE) and whiteness index (DWI) promoted by at-home and in-office bleaching. Enamel surface was submitted to (n=10): at-home (10%, 15%, 20% carbamide peroxide - CP, 6% hydrogen peroxide -HP) and three 35% HP agents with light irradiation (LED, laser, and halogen) or no treatment (control). The DR and pH of agents were measured after 0, 2, 4, 6 and 8 h (at-home) or after 5, 15, 20, 30 and 40 min (in-office). Color parameters (L*, a*, b*, DE, DWI) were determined at baseline and after bleaching. DR, pH, L*, a*, b* data were analyzed by one-way (at-home) or two-way (in-office) repeated measures ANOVA and Tukey test. DE and DWI, by one-way (at-home) or two-way (in-office) ANOVA and Tukey test. DR of at-home agents was similar after 6 and 8 h (p>0.05), with pH close to neutral (6.5 to 6.9, CP) or acid 5.9 (6% HP). From 4 to 8 h, DE was higher for 15% and 20% CP compared with 10% CP (p<0.05). After 40 min, DR of 35% HP agents was similar and all exhibited significant DE in one application (p<0.05), regardless light irradiation. DWI indicated whitening effect with no differences among groups (p>0.05). One 35% HP showed alkaline pH, and the others, pH < 5.5. At-home agents could be applied for 2 h (15%, 20% CP, 6% HP) and 4 h (10% CP) and the in-office agents, up to 40 min in one application, without light.

Resumo Este estudo avaliou a taxa de decomposição (DR), pH, alteração da cor do esmalte (∆E) e índice de clareamento (DWI) promovido por agentes clareadores caseiros e de consultório. A superfície do esmalte foi submetida a (n=10): agentes caseiros (10%, 15%, 20% de peróxido de carbamida - CP e 6% de peróxido de hidrogênio - HP) e três agentes a base de HP a 35% comirradiação por luz (LED, laser e halógena) ou sem tratamento (controle). A DR e pH dos agentes foi mensurada após 0, 2, 4, 6 e 8h (agentes caseiros) e após 5, 15, 20, 30 e 40 min (agentes de consultório). Parâmetros de cor (L*, a*, b*, DE e DWI) foram determinados inicialmente e após clareamento. Os dados da DR, pH, L*, a*, b* foram analisados por ANOVA um fator (agentes caseiros) ou dois fatores (agentes de consultório) de medidas repetidas e teste Tukey. ΔE e DWI por ANOVA um fator (agentes caseiros) e dois fatores (agentes de consultório) e teste Tukey. A DR dos agentes clareadores caseiros foi similar após 6 e 8 h (p>0.05), com pH próximo ao neutro (6,5 a 6,9 - CP) ou ácido (5,9- HP 6%). De 4 a 8 h, a ∆E foi maior para CP 15% e 20% comparado ao CP 10% (p<0.05). Após 40 min, a DR dos agentes HP 35% foi similar e todos exibiram ∆E significante em uma aplicação (p<0.05), independente da aplicação de luz. DWI indicou efeito clareador, sem diferenças entre os grupos (p>0.05). Um agente HP 35% exibiu pH alcalino, e os outros, pH<5.5. Os agentes clareadores caseiros poderiam ser aplicados por 2 h (15%, 20% CP e 6% HP) e 4 h (CP 10%), e os agentes clareadores de consultório, até 40 min em uma aplicação, sem luz.

O lado negro dos clareadores cutâneos / The dark side of skin lightening

Esta carta traz uma reflexão surgida a partir da palestra da professora Fatimata Ly, da University Cheikh Diop de Dakar (África), no último Congresso da Academia Europeia de Dermatologia, em Paris. A professora F. Ly proferiu a palestra Depigmentation: when, where and how. O tom de pele uniforme é um dos critérios de beleza. Esta carta não diz respeito aos pacientes que chegam ao consultório médico e que são cuidadosamente acompanhados e monitorados por dermatologistas criteriosos. Ela quer chamar a atenção para os indivíduos que não chegam aos consultórios, que repetem prescrições de conhecidos ou que mantêm por tempo indefinido uma prescrição realizada por dermatologista numa consulta pontual. Recentemente, participei, de forma anônima, de fóruns de "discussão" na internet de pessoas leigas sobre melasma. A intensidade e a velocidade do compartilhamento em relação àquilo que eles aconselham são expressivas. A criatividade é enorme ao sugerirem usar produtos que podem causar algum dano. Entre os clareadores mais utilizados estão esteroides, hidroquinona, mercúrio e ácidos. Há que se realizar uma campanha de conscientização da população em relação aos perigos de se utilizarem despigmentantes cutâneos sem indicação precisa do médico dermatologista.

This letter is a reflection that arose from the lecture given by Professor Fatimata Ly, from University Cheikh Diop in Dakar (Africa) in the latest Congress of the European Academy of Dermatology and Venereology in Paris. Professor F. Ly gave the lecture "Depigmentation: when, where and how". An even skin tone is one of the criteria for beauty. This letter does not concern those patients that come to our practices and are carefully followed and monitored by discerning dermatologists. She wants to raise attention to those that do not come to our practices, that use prescriptions given to acquaintances, or that use a dermatologist prescription indefinitely, after a single consultation. I was recently part of "discussion" forums over the internet, anonymously, of lay people on melasma. The intensity and speed of sharing of what they recommend using are impressive. They are very creative suggesting the use of products that could cause harm. Among the most used lightening products are steroids, hydroquinone, mercury and acids. There must be an awareness campaign to warn the population regarding the dangers of using skin depigmenting agents without a specific indication by the dermatologist.

Effects of pH, Temperature and Agitation on the Decolourisation of Dyes by Laccase-Containing Enzyme Preparation from Pleurotus sajor-caju

(1) Background: In this study, the effects of different pH values ​​(2.4, 3.2, 4.4 and 5.0), temperatures (30, 35, 40, 45 and 50°C) and agitation (100 rpm) on the enzymatic decolourisation of twenty-two dyes belonging to the chromophore groups anthraquinone, azo and triphenylmethane were assessed. (2) Methods: In all conditions, it was used a crude enzyme broth containing 30 U mL-1 laccases produced by Pleurotus sajor-caju PS-2001 in submerged process. (3) Results: Regarding the effects of pH values, the best results were obtained at pH 3.2 and 30°C, in which bleaching was observed for all dyes evaluated. In assays conducted at different temperatures, highest levels of decolourisation were observed at 35°C and pH 3.2 for nineteen of the dyes assessed. Thirteen dyes presented colour reduction exceeding 50% after the enzymatic treatment, including all acid and all disperse dyes evaluated. The reciprocal agitation of 100 rpm promoted negative effect on decolourisation. (4) Conclusion: From the results achieved, one can conclude that the laccase-containing preparation of P. sajor-caju PS-2001 has potential for the decolourisation of some dyes widely used in different industrial sectors, especially in the textile industry, and therefore could be used in future strategies for the biotreatment of coloured wastes.

Effect of different bleaching agents on the surface roughness and color stability of feldspathic porcelain / Efeito de diferentes agentes de clareamento na rugosidade superficial e estabilidade de cor da porcelana feldspática

Objective: The aim of this study was to evaluate the effect of different bleaching agents on the surface roughness and color stability of feldspathic porcelain. Material and Methods: In this study, totally 40 discshaped Noritake and Ceramco 3 feldspathic porcelain and two bleaching agents (Opalescence Boost and Opalescence Pf) were used. Bleaching agents were exposed to specimens according to their protocol. Then, the surface roughness of the specimens was evaluated with profilometer and the color of the specimens was recorded by colorimeter. Statistical analysis of the data was performed with IBM SPSS Statistics 20. Results: The results showed that that there were statistically significant differences between the bleaching agents on the surface roughness of feldspathic porcelain (p0.05). Conclusion: The obtained data presented that the bleaching agents increased the surface roughness and not affect the color stability of the feldspathic porcelain. (AU)

Objetivo: O objetivo deste estudo foi avaliar o efeito de diferentes agentes clareadores sobre a rugosidade superficial e estabilidade de cor da porcelana feldspática. Material e Métodos: Neste estudo, foram utilizados 40 porcelanas feldspáticas Noritake e Ceramco 3, em forma de disco, e dois agentes clareadores (Opalescence Boost e Opalescence Pf). Os agentes clareadores foram expostos às amostras de acordo com seu protocolo. Em seguida, a rugosidade superficial dos corpos de prova foi avaliada com perfilômetro e a cor dos corpos de prova foi registrada por colorímetro. A análise estatística dos dados foi realizada com o IBM SPSS Statistics 20. Resultados: Os resultados mostraram que houveram diferenças estatisticamente significantes entre os agentes clareadores na rugosidade superficial da porcelana feldspática (p 0,05). Conclusão: Os dados obtidos mostraram que os agentes clareadores aumentaram a rugosidade superficial e não afetaram a estabilidade de cor da porcelana feldspática.(AU)

Tooth whitening effects of manicure-type hydrogen peroxide tooth whitening gel / 대한구강보건학회지

OBJECTIVES: To examine the tooth whitening effects of a 3% hydrogen peroxide gel.METHODS: Twenty participants were given experimental tooth whitening gels containing 3% hydrogen peroxide, and another 20 participants, who served as the control group, were given tooth whitening gels that contained no hydrogen peroxide. Both groups used their respective whitening agents for 1 week, and tooth lightness was examined at baseline and 4 and 7 days after the experiment.RESULTS: Compared with the control group, in the experimental group, lightness values, determined using VITA classical A1-D4® and VITA SYSTEM 3D-MASTER®, were significantly increased after using the 3% hydrogen peroxide whitening agent (P < 0.01) both 5 and 7 days post-application (P < 0.05).CONCLUSIONS: The study findings confirmed that an improved tooth whitening effect could be expected with the use of a new type of whitening gel containing 3% hydrogen peroxide.

Avaliação in vitro do efeito de dentifrícios branqueadores contendo blue covarine sobre o esmalte dentário bovino / In vitro evaluation of the effect of bleaching dentifrices containing blue covarine on bovine dental enamel

Introdução: O blue covarine é um agente branqueador que promove mudanças ópticas na superfície dos dentes, associado aos abrasivos dos dentifrícios, colaborando para o branqueamento dentário. Objetivo: Determinar as alterações de cor, rugosidade e massa do esmalte bovino, após escovação simulada com dentifrícios branqueadores contendo blue covarine nos tempos 6, 12 e 24 meses. Material e método: 80 corpos de prova (CP) foram divididos em 8 grupos (n = 10): grupo controle (GC-água) e 7 grupos teste (GT1-Colgate Total 12, GT2-Oral-B 3D White Perfection, GT3-Colgate Luminous Instant White, GT4-Close Up White Diamond Attraction, GT5-Close Up White-Glacier Fresh, GT6-Sorriso Xtreme White, GT7-Colgate Luminous White Advanced). Os CP foram escurecidos com café e submetidos à escovação simulada por 6, 12 e 24 meses. As avaliações de cor, rugosidade e massa foram realizadas após cada período de escovação. Resultado: Nenhum dentifrício teste promoveu alterações significativas na rugosidade e massa dos CP, contudo, quando comparados ao GC todos promoveram branqueamento significativo. A comparação dos grupos teste não demonstrou diferença significativa na variação de cor entre GT1, GT2, GT3, GT5, GT6 e GT7 nos tempos estudados. O GT4 apresentou comportamento variável de acordo com o tempo, não diferindo estatisticamente de GT3 aos 6, 12 e 24 meses, de GT6 aos 6 e 12 meses e de GT7 aos 12 meses. Conclusão: O efeito branqueador dos dentifrícios contendo blue covarine , após 2 anos de escovação, parece estar relacionado principalmente com a sua associação aos agentes branqueadores mecânicos, que promoveram o polimento das superfícies dentárias.

Introduction: Blue covarine is a bleaching agent that produces optical changes on the surface of the teeth, associated with the abrasives of the dentifrice leading to tooth whitening. Objective: To determine the changes in colour, roughness and mass of the bovine enamel, after simulated brushing with dentifrices - containing blue covariate bleaching - for 6, 12 and 24 months. Material and method: 80 specimens were divided into 8 groups (n = 10): Control group (CG-water) and 7 test groups (TG1-Colgate Total 12, TG2-Oral-B 3D White Perfection, TG3 -Colgate Luminous Instant White, TG4-Close Up White Diamond Attraction, TG5-Close Up White Now-Glacier Fresh, TG6-Sorriso Xtreme White, TG7-Colgate Luminous White Advanced). The specimens were stained with coffee and subjected to simulated brushing for 6, 12 and 24 months. The colour, roughness and mass evaluations were performed after each brushing period. Result: No dentifrice test produced significant alterations in the roughness and mass of the specimens, however, when compared to CG, all of themproduced significant whitening. The comparison of the test groups did not show a significant difference in the colour variation between TG1, TG2, TG3, TG5, TG6 and TG7 in the study. The TG4 presented a variable behavior according to time, not statistically differing from TG3 at 6, 12 and 24 months, neither from TG6 at 6 and 12 months nor from TG7 at 12 months. Conclusion: The whitening effect of dentifrices containing blue covarine, after long periods of brushing, seems to be related mainly to association with mechanical bleaching agents, which, despite abrasives, did not damage the dental structure.

Longevidade, efetividade, segurança e impacto na qualidade de vida relacionada à saúde bucal das técnicas de clareamento dentário caseiro e de consultório com peróxidos de baixa concentração: ensaio clínico randomizado / Longevity, effectiveness, safety and impact on oral health-related quality of life of at-home and in-office dental bleaching with low concentration peroxides: a randomized clinical trial

O objetivo desse estudo foi avaliar a longevidade, efetividade, segurança e o impacto na qualidade de vida relacionada à saúde bucal das técnicas de clareamento dentário utilizando baixas concentrações de peróxidos. Realizou-se um ensaio clínico randomizado, paralelo e simples cego. Os 81 participantes foram separados em três grupos (n=27): CP10%= Caseiro / peróxido de carbamida 10%(2 horas por dia durante 21 dias); HP6%= Consultório / peróxido de hidrogênio 6% (30 min/ sessão, 3 sessões, ativação luz LED/Laser); HP15%= Consultório / peróxido de hidrogênio 15% (30 min/ sessão, 3 sessões, ativação luz LED/Laser). A cor dos dentes foi avaliada em 5 momentos distintos: T1 (Baseline) = Antes do tratamento; T2 = 1 semana após o início do tratamento; T3 = 2 semanas após o início do tratamento; T4 = 1 semana após o final do tratamento e T5 = 6 meses após o final do tratamento, utilizando a escala de cor Vita Clássica e espectrofotômetro Vita Easy Shade Advance. A sensibilidade dentária foi avaliada utilizando a Escala Visual Numérica e a irritação gengival por meio do Índice Gengival Modificado - IGM. Para avaliação do impacto do clareamento na qualidade de vida utilizou-se o Oral Impact on Daily Performance (OIDP). Os dados foram analisados pelos testes de Friedman, Mann-Whitney, Qui-quadrado de Pearson e McNemar (p<0,05). Os resultados foram distribuídos em 2 artigos, de acordo com as comparações dos grupos CP10% e HP6% no primeiro artigo, e HP6% e HP15% no segundo artigo. No primeiro artigo, houve diferença estatisticamente significativa na mudança de cor (ΔE) de T1 para T4 em CP10% (p<0,001) e HP6% (p<0,001). Observou-se uma diferença significativa de ΔE em T4 entre CP10% (9,28) e HP6% (4,47) (p=0,042). A sensibilidade dentária foi significativamente maior (p=0,008) em CP10% (mediana=1,5) do que em HP6% (mediana=0,0), em T2. A irritação gengival diferiu significativamente (p=0,002) entre CP10% (mediana=0,2) e HP6% (mediana = 0,0), em T2. No segundo artigo não foram observadas diferenças significativas em relação aos parâmetros L*, a* ou b*, entre HP6% e HP15% de T1 a T5. Não foram observadas diferenças significativas entre os grupos HP6% e HP15% na sensibilidade dentária ou irritação gengival. Todos os protocolos utilizados apresentaram efetividade de clareamento. A técnica de consultório com HP6% e HP15% ocasionou baixa frequência de efeitos negativos como sensibilidade e irritação gengival. Nos dois artigos não houveram diferenças dos grupos quanto ao impacto na qualidade de vida relacionada à saúde bucal. No artigo um, a maior presença de efeitos negativos na técnica caseira não impactou significativamente a qualidade de vida relacionada à saúde bucal.(AU)

The objective of this study was to evaluate the longevity, effectiveness, safety and impact on oral health related quality of life of teeth whitening techniques using low concentrations of peroxides. A randomized, parallel and single blind trial was conducted. The 81 participants were separated into three groups (n = 27): CP10% = Homemade / 10% carbamide peroxide (2 hours per day for 21 days); HP6% = Office / Hydrogen peroxide 6% (30 min / session, 3 sessions, LED / Laser light activation); HP15% = Office / 15% hydrogen peroxide (30 min / session, 3 sessions, LED / Laser light activation). The color of the teeth was evaluated in 5 different moments: T1 (Baseline) = Before treatment; T2 = 1 week after initiation of treatment; T3 = 2 weeks after initiation of treatment; T4 = 1 week after the end of the treatment and T5 = 6 months after the end of treatment, using the Vita Classical color scale and Vita Easy Shade Advance spectrophotometer. Dental sensitivity was assessed using the Numerical Visual Scale and gingival irritation using the Modified Gingival Index - IGM. Oral Impact on Daily Performance (OIDP) was used to assess the impact of bleaching on quality of life. Data were analyzed by the Friedman, Mann-Whitney, Pearson's and McNemar's Chi-square tests (p <0.05). The results were distributed in 2 articles, according to the comparisons of groups CP10% and HP6% in the first article, and HP6% and HP15% in the second article. In the first article, there was a statistically significant difference in color change (ΔE) from T1 to T4 in CP10% (p <0.001) and HP6% (p <0.001). A significant difference of ΔE in T4 was observed between CP10% (9.28) and HP6% (4.47) (p = 0.042). Dental sensitivity was significantly higher (p = 0.008) in CP10% (median = 1.5) than in HP6% (median = 0.0), in T2. Gingival irritation differed significantly (p = 0.002) between CP10% (median = 0.2) and HP6% (median = 0.0) in T2. In the second article no significant differences were observed in relation to the L *, a * or b * parameters, between HP6% and HP15% of T1 to T5. No significant differences were observed between HP6% and HP15% groups in tooth sensitivity or gingival irritation. All the protocols used showed bleaching effectiveness. The office technique with HP6% and HP15% caused low frequency of negative effects such as sensitivity and gingival irritation. In both articles there were no differences of the groups regarding the impact on quality of life related to oral health. In article one, the greater presence of negative effects in the homemade technique did not significantly affect the quality of life related to oral health.(AU)

Influência de agentes antioxidantes na resistência de união de substratos clareados / Influence of antioxidants on bond strength of bleached dental substrates

A busca pela estética tem levado muitos pacientes ao consultório odontológico, sendo o clareamento de dentes vitais alternativa não invasiva, quando comparado à microabrasão, facetas e coroas, além de proporcionar elevado índice de sucesso para o tratamento de dentes escurecidos. Porém, há necessidade de espera de 14-21 dias para a realização de novas restaurações após o clareamento, uma vez que o efeito oxidante nos tecidos dentários pode gerar alterações estruturais no esmalte e redução da resistência de união. Este intervalo de tempo muitas vezes, não condiz com a expectativa dos pacientes, gerando insatisfação. Diante disso, estudos têm sido conduzidos com o objetivo de minimizar ou até mesmo anular o efeito adverso do oxigênio residual, possibilitando a execução pós-clareamento de restaurações adesivas com segurança e eficácia, reduzindo o tempo de espera. Uma das alternativas tem sido a utilização de agentes antioxidantes. Sendo assim, esse trabalho teve como objetivo revisar a literatura em relação aos agentes antioxidantes utilizados, bem como a eficácia dos mesmos na resistência adesiva de materiais restauradores ao substrato dental clareado. Esta revisão foi realizada através de buscas por artigos científicos, em bases de dados como Scielo, Pubmed/ Medline e Cochrane Library, sem limitação de data. Foram abrangidos, no estudo, trabalhos que envolvessem os temas "clareamento dental", "clareadores", "esmalte dentário", "dentina", "antioxidantes" e "resistência à tração", buscando analisar sua relevância clínica e científica. Avaliações que não se enquadravam no assunto principal e respectivos itens avaliados foram excluídas da revisão. Concluiu-se que a utilização de compostos antioxidantes, como o ascorbato de sódio 10% (gel e solução), proantocianidinas, catalase, chá verde 10% e alfa-tocoferol tem demonstrado efetividade na reversão dos valores de resistência de união ao esmalte clareado quando aplicados por 10 minutos (ascorbato em solução e proantocianidinas), 20 minutos (catalase), 60 minutos (chá verde, ascorbato gel e alfa-tocoferol), após o clareamento.

The search for esthetic has led many patients to the dental office, becoming the whitening of vital teeth a noninvasive alternative when compared to microabrasion, veneers and crowns, besides providing high success rate for the treatment of discolored teeth. However, there is a necessity to wait for 14-21 days to carry out new restorations after bleaching, since the oxidizing effect on dental tissues can cause structural changes in the enamel and reduction of bond strength. This time interval often does not match the expectations of patients, causing dissatisfaction. In view of this, studies have been conducted in order to minimize or even cancel the adverse effect of residual oxygen, enabling the post-bleaching performance of adhesive restorations safely and effectively, reducing the waiting time. One of the alternatives has been the use of antioxidant agents. Thus, this study aimed to review the literature in relation to the antioxidant agents used as well as their effectiveness in bond strength of restorative dental materials to the bleached substrates. This review was performed by searching for scientific articles in databases such as Scielo, PubMed / Medline and Cochrane Library, without limitation of date. It was included in the study, researches involving the themes "Tooth whitening", "Bleaching agents", "Enamel", "Dentin", "Antioxidants" and "Tensile Strength", searching to analyze its clinical and scientific relevance. The assessments that did not fit the main subject and adjacent items evaluated were excluded from the review. It can be concluded that the use of antioxidant compounds, such as 10% sodium ascorbate (gel and solution), proanthocyanidins, catalase, 10% green tea and alpha-tocopherol, have shown effectiveness in reversion of the bond strength values to bleached enamel when applied for 10 minutes (ascorbate solution and proanthocyanidins), 20 minutes (catalase), 60 minutes (green tea, gel ascorbate and alpha-tocopherol), after bleaching.

Sageretia thea fruit extracts rich in methyl linoleate and methyl linolenate downregulate melanogenesis via the Akt/GSK3β signaling pathway

BACKGROUND/OBJECTIVES: Sageretia thea is traditionally used as a medicinal herb to treat various diseases, including skin disorders, in China and Korea. This study evaluated the inhibitory effect of Sageretia thea fruit on melanogenesis and its underlying mechanisms in B16F10 mouse melanoma cells. The active chemical compounds in anti-melanogenesis were determined in Sageretia thea. MATERIALS/METHODS: Solvent fractions from the crude extract were investigated for anti-melanogenic activities. These activities and the mechanism of anti-melanogenesis in B16F10 cells were examined by determining melanin content and tyrosinase activity, and by performing western blotting. RESULTS: The n-hexane fraction of Sageretia thea fruit (HFSF) exhibited significant anti-melanogenic activity among the various solvent fractions without reducing viability of B16F10 cells. The HFSF suppressed the expression of tyrosinase and tyrosinase-related protein 1 (TRP1). The reduction of microphthalmia-associated transcription factor (MITF) expression by the HFSF was mediated by the Akt/glycogen synthase kinase 3 beta (GSK3β) signaling pathway, which promotes the reduction of β-catenin. Treatment with the GSK3β inhibitor 6-bromoindirubin-3'-oxime (BIO) restored HFSF-induced inhibition of MITF expression. The HFSF bioactive constituents responsible for anti-melanogenic activity were identified by bioassay-guided fractionation and gas chromatography-mass spectrometry analysis as methyl linoleate and methyl linolenate. CONCLUSIONS: These results indicate that HFSF and its constituents, methyl linoleate and methyl linolenate, could be used as whitening agents in cosmetics and have potential for treating hyperpigmentation disorders in the clinic.

Efecto del tipo y del número de lavados en la eficacia de mosquiteros tratados con deltametrina de larga duración para el control de Aedes aegypti en Girardot, Colombia / Effect of the type and number of washes in the efficacy of long lasting insecticidal nets for Aedes aegypti control in Girardot, Colombia

Resumen Introducción. El uso de mosquiteros tratados con insecticida en fórmulas de larga duración ha demostrado resultados prometedores en el control de Aedes aegypti. Objetivo. Evaluar la eficacia de mosquiteros impregnados con deltametrina en una fórmula de larga duración para el control de A. aegypti en Girardot, Colombia, después de tres lavados. Materiales y métodos. Se hicieron bioensayos de eficacia de los mosquiteros contra A. aegypti silvestres después de utilizar los siguientes tres productos de lavado, siguiendo la metodología de la Organización Mundial de la Salud: detergente en polvo, detergente en polvo y blanqueador, y jabón de barra, todos utilizados hasta en 20 lavados. Resultados. El tipo de producto de lavado y el número de lavados afectaron significativamente la eficacia de los mosquiteros impregnados con deltametrina. El lavado con jabón de barra presentó el mayor efecto, pues en tan solo seis lavados la mortalidad bajó a 50 % (25/50), en contraste con 66 % (33/50 de mortalidad después del lavado con detergente en polvo y de 84 % (42/50) después del lavado con detergente y blanqueador. En cuanto al número de lavados, el jabón en barra también causó una mayor reducción de la eficacia: a 68 % con solo tres lavados. Conclusión. La eficacia de los mosquiteros impregnados con deltametrina de larga duración en el control de A. aegypti varió con el tipo de producto de lavado y el número de lavados, siendo el jabón en barra el que redujo su eficacia en mayor medida. Se requieren nuevos estudios para establecer la disminución en la concentración del insecticida entre lavados.

Abstract Introduction: The use of long lasting insecticidal materials has shown promising results in the control of Aedes aegypti. Objective: To evaluate the efficacy of long-lasting insecticidal nets (PermaNet®) for Aedes aegypti control after three washing treatments in the city of Girardot, Colombia. Materials and methods: Standard bioassays were conducted with the nets following the World Health Organization protocols using wild A. aegypti after three washing treatments: (1) Detergent powder, (2)detergent powder and bleach, and (3) bar soap, until completing 20 washes. Results: The type and number of wash treatments had a significant effect on net efficacy. Greater effects in the insecticide bioavailability were seen for the bar soap treatment. After six washes, mortality decreased by 50% (25/50), vs 66% (33/50) for the detergent powder and 84% (42/50) for the detergent powder and bleach treatments. Regarding the number of washes, the bar soap treatment reduced the efficacy to 68% after only three washes. Conclusion: The effectiveness of long-lasting insecticidal nets (PermaNet 2.0) for A. aegypti control varied in relation to the treatment and number of washes. The bar soap treatment resulted in the greatest reduction of mortality. Further studies on insecticidal reductions are needed under local conditions.