RESUMO

OBJECTIVE: To compare at-home systems with reduced daily time of use (10% hydrogen peroxide [HP] gel with prefilled (PT) or customized trays (CT), and 10% carbamide peroxide [CP] gel), with the conventional nightguard vital bleaching (10% CP). Bleaching efficacy, adverse effects, and patient's satisfaction were evaluated. METHODS: Sixty participants were randomly divided into treatments (14 days): Opalescence GO (OGO)-10%HP PT-30 min, White Class-10%HP CT-30 min, Opalescence PF-10%CP CT-2 h, and Opalescence PF-10%CP CT-8 h. Color difference (visual and spectrophotometer), tooth sensitivity (visual analogue scale), gingival condition (Löe index), enamel mineralization (laser fluorescence), and patients' satisfaction (questionnaire) were assessed. Statistical tests were applied (5%). RESULTS: After 1 year, color difference was similar for the groups (p > 0.05). All groups showed similar sensitivity risk (p > 0.05). The intensity of sensitivity and gingival irritation was mild for all gels, but higher for OGO. Fluorescence after bleaching remained similar to those of sound enamel. All participants were satisfied with treatments. CONCLUSIONS: All systems produced similar bleaching efficacy, which was maintained after 1 year. Patients were satisfied with bleaching outcomes. Tooth sensitivity occurred in all groups, but with overall mild intensity. No relevant gingival irritation and enamel demineralization was observed. CLINICAL SIGNIFICANCE: Bleaching with 10% HP gels in prefilled and CTs represent efficacious alternative for tooth color change, with patients' acceptance similar to conventional 10% CP. Patients must be warned about the mild sensitivity and gingival irritation potential, mainly with PTs.

Assuntos

Sensibilidade da Dentina , Clareadores Dentários , Clareamento Dental , Seguimentos , Humanos , Peróxido de Hidrogênio , Peróxidos , Ureia

RESUMO

PURPOSE: This crossover study evaluated the hydrogen (HP) and carbamide (CP) peroxide degradation of bleaching gels in prefilled (PT) and customized trays (CT). METHODS: Volunteers were randomly allocated to treatments (n=10) : PT-HP/OGO (Opalescence GO-10%); CT-HP/WTC (White Class-10%) or CT-CP/OPF (Opalescence PF-10%). Gel samples were collected from the upper and lower trays in each period (baseline, 15, 30, 50 and 120 minutes). HP concentration was determined with the potassium permanganate titration method. Degradation was calculated based on initial concentration of gels. Repeated measures two-way ANOVA and Tukey's test (5%) were applied. RESULTS: Bleaching gels exhibited exponential degradation over time. In 30 minutes, no significant differences in degradation among them were detected (P= 0.13). After 2 hours, lower degradation of CT-CP/OPF (61.85±10.65), compared with hydrogen peroxide in PT and CT (71.55±8.24 and 78.69±9.33, respectively) was observed. The gels showed higher degradation rate in lower trays than in upper trays in all evaluated times. In general, the bleaching gels in lower trays degraded more than in upper trays. The carbamide peroxide gel presented lower degradation than hydrogen peroxide after 2 hours. The degradation of the 10% hydrogen peroxide gel used in prefilled trays was higher than the one in customized trays after 30 minutes, but after 120 minutes, the degradation rate was similar for both. CLINICAL SIGNIFICANCE: Bleaching gels degraded faster in lower arches than in upper arches. The degradation process was faster in the first 15 minutes of use and depended on the gel's composition, time of use, and tray position in the dental arches.

Assuntos

Clareadores Dentários , Clareamento Dental , Estudos Cross-Over , Humanos , Peróxido de Hidrogênio , Peróxidos , Ureia

RESUMO

The aim of this study was to evaluate the anti-erosive effect of solutions containing sodium fluoride (F: 225 ppm F-), stannous chloride (Sn: 800 ppm Sn2+), and some film-forming polymers (Gantrez: Poly [methylvinylether-alt-maleic anhydride]; PGA: propylene glycol alginate; Plasdone: poly[vinylpyrrolidone]; and CMC: carboxymethylcellulose). Solutions were tested in an erosion-remineralization cycling model, using enamel and dentin specimens (n = 10, for each substrate). Distilled water was the negative control. Cycling consisted of 120 min immersion in human saliva, 5 min in 0.3% citric acid solution, and 120 min of exposure to human saliva, 4×/day, for 5 days. Treatment with solutions (pH = 4.5) was carried out 2×/day, for 2 min. Surface loss (SL) was evaluated with optical profilometry. Zeta potential of hydroxyapatite crystals was determined after treatment with the solutions. Data were statistically analyzed (α = 0.05). For enamel, all polymers showed significantly lower SL (in µm) than the control (11.09 ± 0.94), except PGA (10.15 ± 1.25). PGA significantly improved the protective effect of F (4.24 ± 0.97 vs. 5.64 ± 1.60, respectively). None of the polymers increased the protection of F+Sn (5.13 ± 0.78). For dentin, only Gantrez (11.40 ± 0.97) significantly reduced SL when compared with the negative control (12.76 ± 0.75). No polymer was able to enhance the effect of F (6.28 ± 1.90) or F+Sn (7.21 ± 1.13). All fluoridated solutions demonstrated significantly lower SL values than the control for both substrates. Treatment of hydroxyapatite nanoparticles with all solutions resulted in more negative zeta potentials than those of the control, except Plasdone, PGA, and F+Sn+PGA, the latter two presenting the opposite effect. In conclusion, Gantrez, Plasdone, and CMC exhibited an anti-erosive effect on enamel. PGA increased the protection of F. For dentin, only Gantrez reduced erosion.

Assuntos

Fluoreto de Sódio/química , Compostos de Estanho/química , Erosão Dentária/prevenção & controle , Alginatos , Carboximetilcelulose Sódica , Humanos , Técnicas In Vitro , Maleatos , Polímeros , Polivinil , Povidona , Fluoretos de Estanho

RESUMO

AIM: This study evaluated the efficacy of self-etching adhesive systems associated or not associated with the neodymium-doped yttrium aluminum garnet (Nd:YAG) laser on the protection against enamel erosive/abrasive wear. MATERIALS AND METHODS: Bovine enamel specimens were demineralized with 0.3% citric acid (5 minutes). The samples were randomly assigned to eight groups (n = 20): SB - Single Bond Universal (3M/ESPE); SB+L - Single Bond Universal + laser (80 mJ/10 Hz); FB - Futurabond U (Voco); FB+L -Futurabond U + laser; GEN - G-aenial bond (GC); GEN+L -G-aenial bond + laser; L - laser irradiation; and C - no treatment. The laser was applied before light curing. The samples were subjected to erosive/abrasive challenges (0.3% citric acid - 2 minutes and tooth brushing four times daily for 5 days). Enamel surface loss was recovered profilometrically by comparison of baseline and final profiles. The adhesive layer thickness, retention percentage of the protective layer, and microhardness of cured adhesive were measured. Data were analyzed using one-way analysis of variance and Tukey's test (5%). RESULTS: There were significant differences for all parameters (p = 0.0001). Mean values ± SD and results of the Tukey's test were: Surface wear: GEN - 4.88 (±1.09)a, L - 5.04 ± 0.99)a, FB - 5.32 (±0.93)ab, GEN + L - 5.46 (±1.27)abc, SB + L - 5.78 (±1.12)abc, FB + L - 6.23 (±1.25)bc, SB - 6.35 (±1.11)c, and C - 6.46 (±0.61)c; layer thickness: GEN - 15.2 (±8.63)c, FB - 5.06 (±1.96)a, GEN + L - 13.96 (±7.07)bc, SB + L - 4.24 (±2.68)a, FB + L - 9.03 (±13.02)abc, and SB - 7.49 (±2.80)ab; retention: GEN - 68.89 (±20.62)c, FB - 54.53 (±24.80)abc, GEN + L - 59.90 (±19.79)abc, SB + L - 63.37 (±19.30)bc, FB + L - 42.23 (±17.68) a, and SB - 47.78 (±18.29)ab; microhardness: GEN - 9.27 (±1.75)c; FB - 6.99 (±0.89)b; GEN + L - 6.22 (±0.87)ab; SB + L - 15.48 (±2.51)d; FB + L - 10.67 (±1.58)c; SB - 5.00 (±1.60)a. CONCLUSION: The application of Futurabond U and G-aenial bond on enamel surface, as well as the Nd:YAG laser irradiation alone, was able to reduce the enamel wear. The use of laser after the adhesive systems did not improve their efficacy. CLINICAL SIGNIFICANCE: Erosive/abrasive wear is a prevalent condition in clinical practice affecting many patients. The association of adhesive systems and Nd:YAG laser is of considerable clinical interest because it assesses new treatments to reduce the erosive/abrasive wear that would help dentists in clinical treatment decisions to reduce enamel wear and achieve a successful treatment.

Assuntos

Cimentos Dentários/uso terapêutico , Esmalte Dentário/lesões , Abrasão Dentária/prevenção & controle , Desgaste dos Dentes/prevenção & controle , Animais , Bovinos , Lasers de Estado Sólido/uso terapêutico

RESUMO

This study aimed to perform a systematic review and meta-analysis of the literature to determine the effects of the use of mouthguards (MGs) on cardiopulmonary capacity in athletes (oxygen uptake: VO 2 max, and minute ventilation: VE max). Seven electronic databases and reference lists of relevant papers were searched for randomized clinical trials (RCTs) that compared the cardiopulmonary capacity in athletes with and without the use of an MG. The risk of bias tool of the Cochrane Collaboration was used for quality assessment. Fourteen studies were included. For both the overall VO2 max and VE max analyses, significant differences were observed between the MG and no MG conditions, favoring no MG, which presented the highest VO2 max values (p=0.0001; 95% CI; -2.638 to -1.728) and the highest VE max values (p=0.0001; 95% CI; -4.103 to -1.354). When the results were analyzed separately for each subgroup (type of MG and place of use), the meta-analysis showed that the effect of the use of an MG on VO2 max and VE max was not significant when custom-made MGs were used. The use of an MG overall decreased VO2 max and VE max compared to the control. Nevertheless, custom-made MGs seem to have no effect on these parameters.

RESUMO

OBJECTIVES: To evaluate the anti-erosive potential of solutions containing sodium fluoride (NaF, 225 ppm F) and different film-forming agents. METHODS: In Phase 1, hydroxyapatite crystals were pre-treated with solutions containing NaF (F), linear sodium polyphosphate (LPP), sodium pyrophosphate tetrabasic (PP), sodium tripolyphosphate (STP), sodium caseinate (SC), bovine serum albumin (BSA), stannous chloride (Sn) and some combinations thereof. Deionized water was the control (C). The pH-stat method was used to evaluate hydroxyapatite dissolution. In Phase 2, the most effective solutions were tested in two independent experiments. Both consisted of an erosion-remineralization cycling model using enamel and dentine specimens with three solution treatments per day. In Phase 2a, the challenge was performed with 0.3% citric acid (pH=3.8). In Phase 2b, 1% citric acid (pH=2.4) was used. Hard tissue surface loss was determined profilometrically. Data were analyzed with two-way ANOVA and Tukey tests. RESULTS: In Phase 1, F, LPP, Sn and some of their combinations caused the greatest reduction in hydroxyapatite dissolution. In Phase 2a, C showed the highest enamel loss, followed by LPP. There were no differences between all other groups. In Phase 2b: (F+LPP+Sn) < (F+LPP) = (F+Sn) < (F) = (LPP+Sn) < (LPP) < (Sn) < C. For dentine, in both experiments, only the fluoride-containing groups showed lower surface loss than C, except for LPP+Sn in 2a. CONCLUSIONS: F, Sn, LPP reduced enamel erosion, this effect was enhanced by their combination under highly erosive conditions. For dentine, the F-containing groups showed similar protective effect. CLINICAL SIGNIFICANCE: The addition of LPP and/or Sn can improve the fluoride solution protection against erosion of enamel but not of dentine.

Assuntos

Cariostáticos/farmacologia , Fluoreto de Sódio/farmacologia , Remineralização Dentária/métodos , Difosfatos/farmacologia , Humanos , Erosão Dentária/prevenção & controle

RESUMO

This study investigated the effect of a calcium lactate prerinse on sodium fluoride protection in an in vitro erosion-remineralization model simulating two different salivary flow rates. Enamel and dentin specimens were randomly assigned to 6 groups (n = 8), according to the combination between rinse treatments - deionized water (DIW), 12 mM NaF (NaF) or 150 mM calcium lactate followed by NaF (CaL + NaF) - and unstimulated salivary flow rates - 0.5 or 0.05 ml/min - simulating normal and low salivary flow rates, respectively. The specimens were placed into custom-made devices, creating a sealed chamber on the specimen surface connected to a peristaltic pump. Citric acid was injected into the chamber for 2 min, followed by artificial saliva (0.5 or 0.05 ml/min) for 60 min. This cycle was repeated 4×/day for 3 days. Rinse treatments were performed daily 30 min after the 1st and 4th erosive challenges, for 1 min each time. Surface loss was determined by optical profilometry. KOH-soluble fluoride and structurally bound fluoride were determined in specimens at the end of the experiment. Data were analyzed by 2-way ANOVA and Tukey tests (α = 0.05). NaF and CaL + NaF exhibited significantly lower enamel and dentin loss than DIW, with no difference between them for normal flow conditions. The low salivary flow rate increased enamel and dentin loss, except for CaL + NaF, which presented overall higher KOH-soluble and structurally bound fluoride levels. The results suggest that the NaF rinse was able to reduce erosion progression. Although the CaL prerinse considerably increased F availability, it enhanced NaF protection against dentin erosion only under hyposalivatory conditions.

Assuntos

Compostos de Cálcio/uso terapêutico , Lactatos/uso terapêutico , Antissépticos Bucais/uso terapêutico , Saliva/metabolismo , Fluoreto de Sódio/uso terapêutico , Erosão Dentária/prevenção & controle , Animais , Compostos de Cálcio/administração & dosagem , Bovinos , Ácido Cítrico/efeitos adversos , Esmalte Dentário/efeitos dos fármacos , Esmalte Dentário/patologia , Dentina/efeitos dos fármacos , Dentina/patologia , Cultura em Câmaras de Difusão , Progressão da Doença , Fluoretos/análise , Fluoretos/farmacocinética , Técnicas In Vitro , Lactatos/administração & dosagem , Imagem Óptica/métodos , Saliva Artificial/administração & dosagem , Taxa Secretória/fisiologia , Fluoreto de Sódio/administração & dosagem , Fatores de Tempo , Erosão Dentária/patologia , Remineralização Dentária/métodos , Água , Xerostomia/fisiopatologia

RESUMO

This study evaluated the effect of physical and chemical activation on the diffusion time of different concentrations of hydrogen peroxide (HP) bleaching agents through enamel and dentin. One hundred and twenty bovine cylindrical specimens were divided into six groups (n = 20): 20% HP; 20% HP with light activation; 20% HP with manganese gluconate; 35% HP; 35% HP with light activation; and 35% HP with manganese gluconate. The specimens were fixed over transparent epoxy wells with internal cavities to simulate a pulpal chamber. This chamber was filled with an enzymatic reagent to simulate pulpal fluid. The bleaching gels were applied on enamel surface and the image of the pulpal fluid was captured by a video camera to monitor the time of peroxide penetration in each specimen. ANOVA analysis showed that concentration and type of activation of bleaching gel significantly influenced the diffusion time of HP (P < 0.05). 35% HP showed the lowest diffusion times compared to the groups with 20% HP gel. The light activation of HP decreased significantly the diffusion time compared to chemical activation. The highest diffusion time was obtained with 20% HP chemically activated. The diffusion time of HP was dependent on activation and concentration of HP. The higher concentration of HP diffused through dental tissues more quickly.

Assuntos

Peróxido de Hidrogênio/química , Animais , Bovinos , Esmalte Dentário/química , Dentina/química

RESUMO

The objective of this study was to evaluate the color, translucency and fluorescence of bovine enamel and dentin submitted to different bleaching modalities. Pairs of enamel and dentin discs (3 mm in diameter) were obtained from 150 bovine teeth. In 75 of the pairs, one specimen had the enamel removed (Dentin Group). The dentin was removed from one specimen of the remaining 75 pairs (Enamel Group) and the other specimen was left unaltered (Enamel + Dentin). The evaluation of color, translucency and fluorescence was performed with a spectrophotometer using the CIE L* a* b*. Each group was subdivided into three subgroups: Control, composed of specimens that were not bleached, and two experimental subgroups, bleached with either 10% carbamide peroxide (CP10%) or 35% hydrogen peroxide (HP35%). The CP10% bleaching gel was applied 2 h/day for 14 days. The HP35% bleaching agent was applied using two applications of 30 min each, with a one week interval between each application. When not being bleached, the specimens were immersed in artificial saliva. The color, translucency and fluorescence ratings were assessed using spectrophotometry 7 days after the treatment. Regarding color, significant differences were found between bleaching techniques in the groups Enamel and Enamel + Dentin, with a higher color difference for HP35%. Bleaching did not change the translucency of the dental tissues. There were significant differences for fluorescence for the HP35% subgroups of Dentin and Enamel + Dentin, and for the CP10% subgroup of Enamel. Dental bleaching changed the color and fluorescence of the dental tissues, however translucency was not affected.

Assuntos

Esmalte Dentário/efeitos dos fármacos , Dentina/efeitos dos fármacos , Clareadores Dentários/farmacologia , Clareamento Dental , Animais , Peróxido de Carbamida , Bovinos , Cor , Fluorescência , Peróxido de Hidrogênio/farmacologia , Luz , Peróxidos/farmacologia , Ureia/análogos & derivados , Ureia/farmacologia

RESUMO

This in vitro study evaluated the effect of 35% hydrogen peroxide (HP) bleaching gel modified or not by the addition of calcium and fluoride on enamel susceptibility to erosion. Bovine enamel samples (3 mm in diameter) were divided into four groups (n = 15) according to the bleaching agent: control-without bleaching (C); 35% hydrogen peroxide (HP); 35% HP with the addition of 2% calcium gluconate (HP + Ca); 35% HP with the addition of 0.6% sodium fluoride (HP + F). The bleaching gels were applied on the enamel surface for 40 min, and the specimens were subjected to erosive challenge with Sprite Zero and remineralization with artificial saliva for 5 days. Enamel wear was assessed using profilometry. The data were analyzed by ANOVA/ Tukey's test (P < 0.05). There were significant differences among the groups (P = 0.009). The most enamel wear was seen for C (3.37 ± 0.80 µm), followed by HP (2.89 ± 0.98 µm) and HP + F (2.72 ± 0.64 µm). HP + Ca (2.31 ± 0.92 µm) was the only group able to significantly reduce enamel erosion compared to C. The application of HP bleaching agent did not increase the enamel susceptibility to erosion. However, the addition of calcium gluconate to the HP gel resulted in reduced susceptibility of the enamel to erosion.