Regenerative and Protective Effects on Dental Tissues of a Fluoride-Silicon-Rich Toothpaste Associated with a Calcium Booster: An In Vitro Study.

Calcium boosters have been used as a supplement for fluoride toothpastes to repair the dental tissues and reduce dentin permeability. This in vitro study aimed to characterize the regenerative and protective effects of the treatment of dental tissues with a fluoride-silicon-rich toothpaste associated with a calcium booster. Bovine enamel and dentin blocks (n = 5) were obtained (4 × 4 × 6 mm). A fluoride-silicon-rich toothpaste and a calcium booster were used to brush the enamel and dentin both immediately and five days afterwards. The outcomes were then compared to those of the untreated control group. After that, the specimens were cross-sectioned. SEM was used to evaluate the micromorphology of the surface and cross-section. Energy-dispersive X-ray spectroscopy (EDS) was used to determine the elemental analyses (weight%). After treatment for 5 days with a booster/silicon-rich toothpaste, EDS analysis demonstrated that it induced a significant mineral change. It was also able to form a protective silicon-enriched mineral layer on both enamel and dentin surfaces. It was demonstrated in vitro that a fluoride-silicon-rich toothpaste associated with a calcium booster regenerates the dental tissues, remineralizing the enamel structure and occluding the dentin tubules.

Longevity of bonded composite restorations after dentin biomodification with neolignans obtained from Nectandra leucantha / Longevidade de restaurações de resina composta após biomodificação de dentina com neolignanas obtidas de Nectandra leucantha

Objective: This in vitro study evaluated the effect of neolignan-containing solutions on dentin biomodification previously applied to the bonding procedure in adhesive restorations. Material and Methods: Neolignans, dehydrodieugenol B­CP1 and dehydrodieugenol B methyl ether­CP2, were isolated from Nectandra leucanthaand two aqueous solutions containing 0.13% neolignans, 0.2% propylene glycol and 3.0% ethanol were prepared. Bovine teeth were ground flat to obtain 2-mm thick specimens which received resin composite restorations (N=10). The neolignan solutions were applied before the bonding procedure (60 s). Experimental groups were: control, untreated group, 0.12% chlorhexidine gel, 0.13% CP1 solution, and 0.13% CP2 solution. A push-out bond strength test was conducted (0.5 mm/min). Bovine tooth sections (0.5×1.7×7.0 mm) were also obtained to assess the modulus of elasticity and mass change after treatment (N=15). A three-point bending test evaluated the elastic modulus of fully demineralized dentine beams after immersion in the solutions. The data were statistically analyzed (α = 0.05). Results: The bond strength of the restorations to dentin was significantly improved by the treatment with neolignan-containing solutions, irrespective of the evaluation time (p<0.05). After 6 months, a significant reduction in the bond strength was observed in the groups treated with the solutions (p>0.05), but the means were significantly higher than the control groups (p<0.05). The elastic modulus of demineralized dentin was significantly improved after the treatment with the solutions (p<0.05). All groups lost mass weight. Conclusion: The solutions improved the in vitro longevity of bonded restorations, possibly due to the dentin biomodification effect of the neolignans.(AU)

Objetivo: Este estudo in vitro avaliou o efeito de soluções contendo neolignanas na biomodificação da dentina aplicadas previamente à restaurações adesivas. Material e Métodos: Neolignanas, desidrodieugenol B­CP1 e éter metílico de desidrodieugenol B-CP2, foram isolados da espécie Nectandra leucantha e duas soluções aquosas contendo 0,13% de neolignanos, 0,2% de propilenoglicol e 3,0% de etanol foram preparadas. Dentes bovinos foram lixados para obter espécimes de 2 mm de espessura e preparos cavitários restaurados com resina composta (N=10). As soluções foram aplicadas em dentina antes do procedimento adesivo (60 s). Os grupos experimentais foram: controle, grupo não tratado, gel de clorexidina 0,12%, solução de CP1 a 0,13% e solução de CP2 a 0,13%. Foi realizado o teste de resistência de união push-out (0,5 mm/min). O módulo de elasticidade e a alteração de massa após tratamento da dentina (0,5×1,7×7,0 mm) foram também avaliados em teste de flexão de três pontos (N=15). Os dados foram analisados estatisticamente (α=0,05). Resultados: A resistência de união das restaurações à dentina melhorou significativamente com o tratamento com as soluções, independentemente do tempo de avaliação (p<0,05). Após 6 meses, foi observada redução significativa da resistência de união nos grupos tratados com as soluções (p>0,05), com médias significativamente maiores do que nos grupos controle (p<0,05). O módulo de elasticidade da dentina desmineralizada aumentou significativamente após tratamento com as soluções (p<0,05). Todos os grupos perderam massa, independentemente do tratamento. Conclusão: As soluções melhoraram in vitroa longevidade das restaurações adesivas, possivelmente devido ao efeito biomodificador da dentina das neolignanas(AU)

Influence of Dentin Priming with Tannin-Rich Plant Extracts on the Longevity of Bonded Composite Restorations.

OBJECTIVE: This in vitro study evaluated the influence of bioactive plant extracts as dentin biomodifying agents to improve the longevity of bonded restorations. For that, plant extracts were applied to the dentin surface prior to the adhesive system. MATERIALS AND METHODS: Bovine incisors were ground flat to obtain 2 mm thick slices in which conical preparations were made (N = 10). Tannin-containing plant extracts were applied to dentin before the application of the restorative system, as follows: control group (untreated, CTL), chlorhexidine 0.12% (CHX), mastruz (Dysphania ambrosioides, MTZ), cat's claw (Uncaria tomentosa, CTC), guarana (Paullinia cupana, GUA), galla chinensis (Rhus chinensis, GCH), and tannic acid (extracted from Acacia decurrens, TNA). The push-out bond strength test was conducted (0.5 mm/min). Dentin biomodification was assessed by the modulus of elasticity and mass change in bovine tooth sections (0.5 × 1.7 × 7.0 mm). The dentin staining after extract treatments of dentin slices was compared. The dentin surface wettability was also evaluated by means of the contact angles of the adhesive system with the dentin surface and compared with the untreated control group. Data were subjected to ANOVA/Tukey's test (α = 0.05). RESULTS: The bond strength of the restoratives to dentin was not significantly improved by the plant extracts, irrespective of the evaluation time (p > 0.05). Except for TNA, the elastic modulus of demineralized dentin significantly reduced after treatment with the plant extracts (p < 0.05). The dentin staining correlated with the tannin content of the extracts. The contact angle was significantly reduced when treated with CTC, GCH, and TNA. CONCLUSIONS: The tannin-containing extracts had a questionable effect on the longevity of bonded restorations. The dentin modulus was negatively affected by the extract treatments. Although some of the extracts changed the contact angle, which seems to improve the adhesive monomer permeation, the tannin-rich plant extract application prior to adhesive application was proven to be clinically unfeasible due to dentin staining.

Sakuranetin reverses vascular peribronchial and lung parenchyma remodeling in a murine model of chronic allergic pulmonary inflammation.

BACKGROUND AND PURPOSE: Asthma is a disease of high prevalence and morbidity that generates high costs in hospitalization and treatment. Although the airway is involved in the physiopathology of asthma, there is also evidence of the importance of vascular and lung parenchyma inflammation and remodeling, which can contribute to the functional pulmonary alterations observed in asthmatic patients. Our aim was to evaluate treatment using sakuranetin, a flavone isolated from the twigs of Baccharis retusa (Asteraceae), on vascular and lung parenchyma alterations in an experimental murine model of asthma. METHODS: Male BALB/c mice were subjected to a sensitization protocol with ovalbumin for 30days and were treated with or without sakuranetin (20mg/kg/mice) or dexamethasone (5mg/kg/mice); then, the lungs were collected for histopathological analysis. We evaluated extracellular matrix remodeling (collagen and elastic fibers), inflammation (eosinophils and NF-kB) and oxidative stress (8-isoprostane) in the pulmonary vessels and lung parenchyma. The thickness of the vascular wall was quantified, as well as the vascular endothelial growth factor (VEGF) levels. RESULTS: We demonstrated that sakuranetin reduced the number of eosinophils and elastic fibers in both the pulmonary vessels and the lung parenchyma, probably due to a reduction of oxidative stress and of the transcription factor NF-kB and VEGF levels in the lung. In addition, it reduced the thickness of the pulmonary vascular wall. The treatment had no effect on the collagen fibers. In most of the parameters, the effect of sakuranetin was similar to the dexamethasone effect. CONCLUSIONS AND IMPLICATIONS: Sakuranetin had anti-inflammatory and antioxidant effects, preventing vascular and distal parenchyma changes in this experimental model of asthma.

Treatment with triterpenic fraction purified from Baccharis uncinella leaves inhibits Leishmania (Leishmania) amazonensis spreading and improves Th1 immune response in infected mice.

The current medications used to treat leishmaniasis have many side effects for patients; in addition, some cases of the disease are refractory to treatment. Therefore, the search for new leishmanicidal compounds is indispensable. Recently, it was demonstrated that oleanolic- and ursolic-containing fraction from Baccharis uncinella leaves eliminated the promastigote and amastigote forms of Leishmania (Leishmania) amazonensis and L. (Viannia) braziliensis without causing toxic effects for J774 macrophages. Thus, the aim of the present work was to characterize the therapeutic effect of the triterpenic fraction in L. (L.) amazonensis-infected BALB/c mice. Oleanolic- and ursolic acid-containing fraction was extracted from B. uncinella leaves using organic solvents and chromatographic procedures. L. (L.) amazonensis-infected BALB/c mice were treated intraperitoneally with triterpenic fraction during five consecutive days with 1.0 and 5.0 mg/kg of triterpenic fraction, or with 10.0 mg/kg of amphotericin B drug. Groups of mice treated with the triterpenic fraction, presented with decreased lesion size and low parasitism of the skin-both of which were associated with high amounts of interleukin-12 and interferon gamma. The curative effect of this fraction was similar to amphotericin B-treated mice; however, the final dose, required to eliminate amastigotes, was lesser than amphotericin B. Moreover, triterpenic fraction did not cause microscopic alterations in liver, spleen, heart, lung, and kidney of experimental groups. This work suggests that this fraction possesses compounds that are characterized by leishmanicidal and immunomodulatory activities. From this perspective, the triterpenic fraction can be explored as a new therapeutic agent for use against American Tegumentar Leishmaniasis.