Sensitivity to antifungals by Candida spp samples isolated from cases of chronic atrophic candidiasis (CAC) / Sensibilidade a antifúngicos por amostras de Candida spp isoladas de casos de candidíase atrófica crônica (CAC)

Abstract The treatment of choice for chronic atrophic candidiasis (CAC), also known as denture stomatitis, is topical antifungal therapy. This study aimed to isolate, identify, and assess the antifungal susceptibility of Candida species from mucosal sites in denture wearers with a diagnosis of CAC and determine the prevalence of associated variables. The sample consisted of 44 patients wearing complete or partial dentures who had a clinical diagnosis of CAC. Using sterile cotton swabs, specimens were collected from the oral mucosa of all patients and grown at 30ºC for 48 h in CHROMagar Candida, as a means of isolating and screening the species. The complementary identification of the species was performed using the VITEK 2 automated system (BioMérieux), as well as the determination of their susceptibility to antifungal agents. Data were analyzed using the chi-square test. STATA 13.1 was used for statistical analysis (α = 5%). Of 44 patients with CAC, 33 (75%) had lesions classified as Newton type II. Yeasts were isolated in 38 cases. The most prevalent species was Candida albicans. None of the isolates were resistant to the antifungals tested. Our findings suggest that current indications for antifungal agents are appropriate. Also, antifungal susceptibility testing and proper fungal identification can help dentists to determine the optimal course of treatment for CAC.

Resumo O tratamento de escolha para candidíase atrófica crônica (CAC), também conhecida como estomatite protética, é a terapia antifúngica tópica. Este estudo teve como objetivo isolar, identificar e avaliar a susceptibilidade antifúngica de espécies de Candida de locais mucosos em portadores de prótese com diagnóstico de CAC e determinar a prevalência de variáveis associadas. A amostra consistiu em 44 pacientes portadores de próteses completas ou parciais que tiveram um diagnóstico clínico de CAC. Usando swab estéril, foram coletados espécimes da mucosa oral de todos os pacientes e cultivados a 30ºC durante 48 h em CHROMagar Candida, como forma de isolamento e triagem das espécies. A identificação complementar das espécies foi realizada no sistema automatizado VITEK 2 (BioMérieux), bem como a determinação da susceptibilidade delas a agentes antifúngicos. Os dados foram analisados usando o teste do qui-quadrado. O STATA 13.1 foi utilizado para análise estatística (α = 5%). Dos 44 pacientes com CAC, 33 (75%) apresentaram lesões classificadas como Newton tipo II. As leveduras foram isoladas em 38 casos. A espécie mais prevalente foi Candida albicans. Nenhum dos isolados foi resistente aos antifúngicos testados. Nossas descobertas sugerem que as indicações atuais para os agentes antifúngicos são apropriadas. Além disso, testes de susceptibilidade antifúngicos e identificação fúngica adequada podem ajudar os dentistas a determinar o curso ótimo de tratamento para CAC.

Sensitivity to antifungals by Candida spp samples isolated from cases of chronic atrophic candidiasis (CAC).

The treatment of choice for chronic atrophic candidiasis (CAC), also known as denture stomatitis, is topical antifungal therapy. This study aimed to isolate, identify, and assess the antifungal susceptibility of Candida species from mucosal sites in denture wearers with a diagnosis of CAC and determine the prevalence of associated variables. The sample consisted of 44 patients wearing complete or partial dentures who had a clinical diagnosis of CAC. Using sterile cotton swabs, specimens were collected from the oral mucosa of all patients and grown at 30ºC for 48 h in CHROMagar Candida, as a means of isolating and screening the species. The complementary identification of the species was performed using the VITEK 2 automated system (BioMérieux), as well as the determination of their susceptibility to antifungal agents. Data were analyzed using the chi-square test. STATA 13.1 was used for statistical analysis (α = 5%). Of 44 patients with CAC, 33 (75%) had lesions classified as Newton type II. Yeasts were isolated in 38 cases. The most prevalent species was Candida albicans. None of the isolates were resistant to the antifungals tested. Our findings suggest that current indications for antifungal agents are appropriate. Also, antifungal susceptibility testing and proper fungal identification can help dentists to determine the optimal course of treatment for CAC.

Chemical composition of essential oils from the apiaceae family, cytotoxicity, and their antifungal activity in vitro against candida species from oral cavity / Composição química de óleos essenciais da família apiaceae, citotoxicidade e sua atividade antifúngica in vitro contra espécies de candida da cavidade oral

Abstract The aims of this research were: evaluate the chemical composition and the cytotoxicity of the Cuminum cyminum (cumin), Anethum graveolens (dill), Pimpinella anisum (anise) and Foeniculum vulgare (fennel) essential oils, as well as their antifungal activity in vitro against ten Candida spp. isolates. The chemical composition of the oils was analyzed by means of gas chromatography coupled with mass spectrometry (GC/MS). The cytotoxicity assays were performed, using the cell proliferation reagent WST-1 in L929 mouse fibroblasts (20x103 well-1). The determinate the Minimum Inhibitory Concentration (MIC), was performed through the Broth Microdilution technique (CLSI). The chemical main components were the cuminaldehyde (32.66%) for cumin, carvone (34.89%) for the dill, trans-anethole (94.01%) for the anise and anethole (79.62%) for the fennel. Anise and fennel did not were cytotoxic in all the tested concentrations, however the cumin oil was cytotoxic in the concentration of 20 mg.mL-1 and the dill in the concentrations of 20 and 8 mg.mL-1. All yeasts were susceptible against the evaluated essential oils. Cumin presented the lowest MIC against yeasts. We concluded that all the essential oils presented inhibitory action against Candida spp., and C . cyminum, P. anisum and F. vulgare were not cytotoxic in the same minimum inhibitory concentrations for the fungi.

Resumo Os objetivos desta pesquisa foram: avaliar a composição química e a citotoxicidade dos óleos essenciais de Cuminum cyminum (cominho), Anethum graveolens (endro), Pimpinella anisum (erva-doce) e Foeniculum vulgare (funcho), bem como sua atividade antifúngica in vitro contra dez isolados de Candida spp.. A composição química dos óleos foi analisada por meio de cromatografia gasosa acoplada à espectrometria de massa (GC / MS). Os ensaios de citotoxicidade foram realizados, utilizando o reagente de proliferação celular WST-1 em fibroblastos de ratinho L929 (20x103 poço-1). A determinação da Concentração Inibitória Mínima (MIC) foi realizada através da técnica de microdiluição em caldo (CLSI). Os principais componentes químicos foram o cuminaldeído (32.66%) para cominho, carvona (34.89%) para o endro, trans-anetol (94.01%) para erva-doce e anetol (79.62%) para a funcho. O endro e a erva-doce não foram citotóxicos em todas as concentrações testadas, no entanto, o óleo de cominho foi citotóxico na concentração de 20 mg.mL-1 e o endro nas concentrações de 20 e 8 mg.mL-1. Todas as leveduras foram suscetíveis aos óleos essenciais avaliados. O cominho apresentou a menor CIM contra as leveduras. Concluímos que todos os óleos essenciais apresentaram ação inibidora contra Candida spp., e C. cyminum, P. anisum e F. vulgare não foram citotóxicos nas mesmas concentrações inibitórias mínimas para os fungos.

A Randomized Double-blind Clinical Trial of Dentin Surface Treatments for Composite Restorations in Noncarious Cervical Lesions: A 36-month Evaluation.

OBJECTIVE:: This randomized, double-blind clinical trial aimed to evaluate the influence of different dentin surface treatments in noncarious cervical lesions (NCCLs). METHODS AND MATERIALS:: Twenty-nine patients participated in this study. One hundred sixty-five NCCLs were selected and randomly assigned to three groups: G0 (control group) with phosphoric acid etching for 15 seconds; G1: phosphoric acid etching for 30 seconds; and G2: ultrasound probe applied for 30 seconds on the dentin surface. Class V composite resin restorations were performed (Z350, 3M ESPE, St Paul, MN, USA). The restorations were evaluated at baseline and at six, 12, 24, and 36 months according to the World Dental Federation criteria. Survival curves were obtained using the Kaplan-Meier method and the log-rank test. Comparisons between groups and times were performed using the McNemar and Chi-square tests (α =0.05). RESULTS:: The presence of failures due to retention was statistically different among the groups ( p=0.012), and G0 and G2 showed better clinical performance than did G1. Sensitivity decreased over time in all groups. Marginal discoloration, postoperative sensitivity, and marginal adaptation were not different among the groups ( p>0.05). CONCLUSIONS:: The studied dentin surface treatments showed similar clinical performance to the conventional technique at 36 months in terms of marginal discoloration, marginal adaptation, and postoperative sensitivity. In contrast, increased acid-etching time resulted in a higher risk of failure due to retention over time in composite Class V restorations.

Chemical composition of essential oils from the apiaceae family, cytotoxicity, and their antifungal activity in vitro against candida species from oral cavity.

The aims of this research were: evaluate the chemical composition and the cytotoxicity of the Cuminum cyminum (cumin), Anethum graveolens (dill), Pimpinella anisum (anise) and Foeniculum vulgare (fennel) essential oils, as well as their antifungal activity in vitro against ten Candida spp. isolates. The chemical composition of the oils was analyzed by means of gas chromatography coupled with mass spectrometry (GC/MS). The cytotoxicity assays were performed, using the cell proliferation reagent WST-1 in L929 mouse fibroblasts (20x103 well-1). The determinate the Minimum Inhibitory Concentration (MIC), was performed through the Broth Microdilution technique (CLSI). The chemical main components were the cuminaldehyde (32.66%) for cumin, carvone (34.89%) for the dill, trans-anethole (94.01%) for the anise and anethole (79.62%) for the fennel. Anise and fennel did not were cytotoxic in all the tested concentrations, however the cumin oil was cytotoxic in the concentration of 20 mg.mL-1 and the dill in the concentrations of 20 and 8 mg.mL-1. All yeasts were susceptible against the evaluated essential oils. Cumin presented the lowest MIC against yeasts. We concluded that all the essential oils presented inhibitory action against Candida spp., and C . cyminum, P. anisum and F. vulgare were not cytotoxic in the same minimum inhibitory concentrations for the fungi.

Evaluation of the frequency of Candida spp. in hospitalized and non-hospitalized subjects / Avaliação da frequência de candida spp. em indivíduos hospitalizados e não hospitalizados

Abstract The aim of this study was to evaluate the frequency of Candida species between a non-hospitalized and a hospitalized population. For this purpose, samples of saliva were sampled through sterile swabs, moistened in peptone water and rubbed in the oral cavity of 140 individuals, from which, 70 were hospitalized patients from the Medical Clinic of a Teaching Hospital and the other 70 were non-hospitalized subjects. All saliva samples were plated in Sabouraud Dextrose agar added with Chloramphenicol and incubated at 36 °C for 48 hours. The morphology identification was performed through macroscopic and microscopic characterization, the CHROMagar Candida medium and the VITEK® system Yeast Biochemical Card (bio Mérieux SA, France). The results showed a colonization of Candida spp. in 85.7% the hospitalized individuals, where the species found were C. albicans (60%), C. tropicalis (23.4%), C. krusei (3.3%) and Candida spp. (13.3%). In the non-hospitalized individuals the colonization by Candida spp was 47.1%, and the species found were: C. albicans (45.5%), C.krusei (9.1%), C. guilliermondii (9.1% %), C. tropicalis (3.0%), C. famata (3.0%) and Candida spp. (30.3%). In spite of their presence in oral cavity in both groups, Candida spp. was more frequently isolated in hospitalized individuals, who were 6.73 times more likely to have this fungus in the oral cavity and were 3.88 times more likely to have Candida albicans.

Resumo O objetivo deste estudo foi avaliar a frequência de espécies de Candida entre uma população de indivíduos não-hospitalizados e hospitalizados. Para isto, amostras de saliva foram coletadas através de swabs estéreis, umedecidas em água de peptona e friccionadas na cavidade bucal de 140 indivíduos, dos quais 70 eram pacientes internados em uma Clínica Médica de um Hospital Escola e os outros 70 eram indivíduos não hospitalizados sem contato com ambiente hospitalar. Todas as amostras de saliva foram plaqueadas em ágar Sabouraud dextrose adicionadas de cloranfenicol e incubadas a 36 °C durante 48 horas. A identificação morfológica foi realizada através da caracterização macroscópica e microscópica, com o meio CHROMagar Candida e do sistema VITEK® Biochemical Card (bio Mérieux SA, França). Os resultados mostraram uma colonização de Candida spp. em 85,7% dos indivíduos hospitalizados, onde as espécies encontradas foram: C.albicans (60%), C. tropicalis (23,4%), C. krusei (3,3%) e Candida spp. (13,3%). Nos indivíduos não-hospitalizados a colonização por Candida spp foi de 47,1%, e as espécies encontradas foram: C. albicans (45,5%), C. krusei (9,1%), C. guilliermondii (9,1%), C. tropicalis (3,0%), C. famata (3,0%) e Candida spp. (30,3%). Apesar de sua presença na cavidade oral em ambos os grupos, Candida spp. foi mais freqüentemente isolada em indivíduos hospitalizados, que foram 6,73 vezes mais propensos a ter este fungo na cavidade oral e foram 3,88 vezes mais propensos a ter Candida albicans.

Influence of Surface Treatment on Composite Adhesion in Noncarious Cervical Lesions: Systematic Review and Meta-analysis.

The purpose of this study was to analyze the influence of dentin surface treatments on the retention rate of resin composite restorations in non-carious cervical lesions (NCCLs). Seven randomized clinical trials were included in this review. Data regarding retention rate, type of surface treatment, and the main characteristics of studies were analyzed. Two reviewers performed a literature search up to December 2016 in eight databases: PubMed (Medline), Lilacs, Ibecs, Web of Science, BBO, Scopus, Scielo and The Cochrane Library. Only clinical trials evaluating dentin surface treatments in resin composite restoration in NCCLs were included. Noncontrolled clinical trials, reviews, editorial letters, case reports, case series and studies published in a language other than English, Portuguese, or Spanish were not included. The included studies evaluated different surface treatments, such as using an adhesive system with a frictional technique, drying the dentin, and removing sclerotic dentin by using a bur and applying EDTA before primer use. The analysis considering the mechanical removal of dentin surface with a bur and the application of an adhesive system in a frictional mode showed these treatments improved retention rates of the resin composite restorations in NCCLs ( p<0.05). There is evidence in the literature suggesting that the mechanical removal of dentin surface with a bur and the application of an adhesive system in a frictional mode could improve the retention rates of resin composite restorations in NCCLs. However, the studies showed high heterogeneity, and additional clinical trials are needed to determine the best dentin treatment option in NCCLs.

Evaluation of the frequency of Candida spp. in hospitalized and non-hospitalized subjects.

The aim of this study was to evaluate the frequency of Candida species between a non-hospitalized and a hospitalized population. For this purpose, samples of saliva were sampled through sterile swabs, moistened in peptone water and rubbed in the oral cavity of 140 individuals, from which, 70 were hospitalized patients from the Medical Clinic of a Teaching Hospital and the other 70 were non-hospitalized subjects. All saliva samples were plated in Sabouraud Dextrose agar added with Chloramphenicol and incubated at 36 °C for 48 hours. The morphology identification was performed through macroscopic and microscopic characterization, the CHROMagar Candida medium and the VITEK® system Yeast Biochemical Card (bio Mérieux SA, France). The results showed a colonization of Candida spp. in 85.7% the hospitalized individuals, where the species found were C. albicans (60%), C. tropicalis (23.4%), C. krusei (3.3%) and Candida spp. (13.3%). In the non-hospitalized individuals the colonization by Candida spp was 47.1%, and the species found were: C. albicans (45.5%), C.krusei (9.1%), C. guilliermondii (9.1% %), C. tropicalis (3.0%), C. famata (3.0%) and Candida spp. (30.3%). In spite of their presence in oral cavity in both groups, Candida spp. was more frequently isolated in hospitalized individuals, who were 6.73 times more likely to have this fungus in the oral cavity and were 3.88 times more likely to have Candida albicans.

Sensitivity to antifungals by Candida spp samples isolated from cases of chronic atrophic candidiasis (CAC)

Abstract The treatment of choice for chronic atrophic candidiasis (CAC), also known as denture stomatitis, is topical antifungal therapy. This study aimed to isolate, identify, and assess the antifungal susceptibility of Candida species from mucosal sites in denture wearers with a diagnosis of CAC and determine the prevalence of associated variables. The sample consisted of 44 patients wearing complete or partial dentures who had a clinical diagnosis of CAC. Using sterile cotton swabs, specimens were collected from the oral mucosa of all patients and grown at 30ºC for 48 h in CHROMagar Candida, as a means of isolating and screening the species. The complementary identification of the species was performed using the VITEK 2 automated system (BioMérieux), as well as the determination of their susceptibility to antifungal agents. Data were analyzed using the chi-square test. STATA 13.1 was used for statistical analysis ( = 5%). Of 44 patients with CAC, 33 (75%) had lesions classified as Newton type II. Yeasts were isolated in 38 cases. The most prevalent species was Candida albicans. None of the isolates were resistant to the antifungals tested. Our findings suggest that current indications for antifungal agents are appropriate. Also, antifungal susceptibility testing and proper fungal identification can help dentists to determine the optimal course of treatment for CAC.

Resumo O tratamento de escolha para candidíase atrófica crônica (CAC), também conhecida como estomatite protética, é a terapia antifúngica tópica. Este estudo teve como objetivo isolar, identificar e avaliar a susceptibilidade antifúngica de espécies de Candida de locais mucosos em portadores de prótese com diagnóstico de CAC e determinar a prevalência de variáveis associadas. A amostra consistiu em 44 pacientes portadores de próteses completas ou parciais que tiveram um diagnóstico clínico de CAC. Usando swab estéril, foram coletados espécimes da mucosa oral de todos os pacientes e cultivados a 30ºC durante 48 h em CHROMagar Candida, como forma de isolamento e triagem das espécies. A identificação complementar das espécies foi realizada no sistema automatizado VITEK 2 (BioMérieux), bem como a determinação da susceptibilidade delas a agentes antifúngicos. Os dados foram analisados usando o teste do qui-quadrado. O STATA 13.1 foi utilizado para análise estatística ( = 5%). Dos 44 pacientes com CAC, 33 (75%) apresentaram lesões classificadas como Newton tipo II. As leveduras foram isoladas em 38 casos. A espécie mais prevalente foi Candida albicans. Nenhum dos isolados foi resistente aos antifúngicos testados. Nossas descobertas sugerem que as indicações atuais para os agentes antifúngicos são apropriadas. Além disso, testes de susceptibilidade antifúngicos e identificação fúngica adequada podem ajudar os dentistas a determinar o curso ótimo de tratamento para CAC.

Treatment of Fluorosis Spots Using a Resin Infiltration Technique: 14-month Follow-up.

The aim of this study was to report a clinical case of moderate fluorosis spots treated with infiltration of low-viscosity resin. A commercial resin was applied to the facial surfaces on the anterior teeth in both the maxillary and mandibular arches. The white spots of fluorosis lost their whitish appearance and appeared similar to sound enamel. This technique, which might constitute an alternative to white-masking of fluorosis spots, showed optimal esthetic results.

Antifungal susceptibility, exoenzyme production and cytotoxicity of novel oximes against Candida.

Novel oximes were synthesized, their in vitro antifungal activity against Candida was evaluated and their cytotoxicity was determined. The procedure used for the synthesis of the oximes is aligned with the current green chemistry trend; water is employed as the solvent in this reaction. The minimum inhibitory and minimum fungicidal concentrations of the oximes were evaluated using the CLSI M27-A3 method. The influence of these compounds on the inhibition of the production of hydrolytic enzymes, phospholipase and proteinase by Candida was also investigated. The compounds showed a good ability to inhibit phospholipase, with a 50 % reduction in most cases. However, the tested compounds did not affect proteinase. The current results showed a substantial reduction in the phospholipase production, which suggests that compounds of this class may interfere with host infection and disease progression. The oximes examined showed lower fungicidal activities than fluconazole but interfered significantly with the expression of phospholipase. Some of the oximes included in this study could be a suitable matrix for the development of novel antifungal compounds.

Self-etching dental adhesive containing a natural essential oil: anti-biofouling performance and mechanical properties.

This study assessed the anti-biofouling performance of an experimental adhesive system containing a naturally occurring essential vegetable oil and examined the following physical and mechanical properties: water sorption (WS) and solubility (SL), microtensile bond strength to dentin (µTBS), and degree of conversion. The following six groups were tested: a self-etching experimental adhesive containing refined essential oil from the seeds of the Butia capitata tree (EAO); an oil-free version of the experimental adhesive (EANO); one group without adhesive as the control (C); and the three following commercial self-etching adhesives: Clearfil Protect Bond (CPB), Clearfil SE Bond, and Adper SE Plus. The antibacterial effect was estimated by microbiological culture on selective/non-selective media, and the results expressed as colony-forming units per unit weight of dry biofilm (CFU mg(-1)). The data were submitted to ANOVA and Tukey's post hoc test (α = 0.05). After 24 h, pH changes were similar in the storage medium of all tested adhesive systems. EAO showed similar levels of antimicrobial activity in a model biofilm microcosm as the commercial self-etching adhesive CPB. Both were effective against total microorganisms, aciduric bacteria, lactobacilli, and Streptococcus mutans. WS and SL were not affected by the presence of the essential oil; the values of EAO were similar to or less than those of commercial equivalents. The incorporation of an essential oil into an experimental adhesive did not influence its monomer conversion result. Immediate µTBS values of EAO and EANO were similar and were greater than those of commercial equivalents. After storage for 6 months, the µTBS of the EAO decreased significantly and became similar to the values of commercial equivalents, while the strength of the EANO was not affected.

An in vitro biofilm model for enamel demineralization and antimicrobial dose-response studies.

Microcosm biofilms formed in microplates have demonstrated complex community dynamics similar to natural dental biofilm. No simplified microcosm models to evaluate enamel demineralization and dose-response effect to anticariogenic therapies have yet been established, thus this study was designed to develop a pre-clinical model fulfilling this purpose. Experiments were carried out to establish the time of biofilm formation and the sucrose concentration and exposure regimen. Biofilms were initiated from saliva and grown for up to 10 days on bovine enamel discs in 24-well plates, with a saliva analogue medium. Data were collected as pH readings and the percentage enamel surface hardness change. A dose-response evaluation was performed with chlorhexidine, which significantly affected the pH and mineral loss. Overall, the established model parameters, 5 days of biofilm growth with intermittent 1% sucrose exposure of 6 h per day, was suitable as a pre-clinical model for enamel demineralization and dose-response studies.

Atividade antifúngica do extrato aquoso de Arctium minus (Hill) Bernh. (Asteraceae) sobre espécies orais de Candida / Antifungal activity of the aqueous extract from Arctium minus (Hill) Bernh. (Asteraceae) on oral Candida species

Este estudo teve como objetivo avaliar a atividade antifúngica do extrato aquoso de folhas de "bardana" [Arctium minus (Hill) Bernh.], por meio da determinação da Concentração Inibitória Mínima (CIM) e Concentração Fungicida Mínima (CFM) sobre diferentes espécies e linhagens do gênero Candida. Foram incluídas no trabalho as espécies de Candida albicans, C. tropicalis, C. glabrata, C. stellatoidea, C. dubliniensis e C. krusei. Utilizaram-se quatro linhagens de C. albicans e três de C.tropicalis, enquanto que para as demais espécies, apenas uma linhagem foi testada. Estas leveduras foram utilizadas no estudo devido à importância e frequência na cavidade bucal. As leveduras foram submetidas a tratamentos com concentrações do extrato aquoso que variaram de 0,09 a 25 mg mL-1. Os resultados indicaram que concentrações inferiores a 12,5 mg mL-1 não são suficientes para apresentar efeito fungistático ou fungicida. A concentração de 12,5 mg mL-1 apresentou efeito fungistático sobre a maioria das linhagens e espécies testadas (C. albicans 04A e ATCC44858; C. tropicalis 23600 e 23651; C. glabrata; C. stellatoideia; C. dubliniensis e C. krusei). Entretanto, efeito fungicida foi observado apenas sobre a espécie C. krusei (CFM=12,5 mg mL-1). Comportamento diferenciado foi observado entre diferentes linhagens de uma espécie (para C. albicans e C. tropicalis). Assim, a ação antifúngica do extrato aquoso de A. minus (Hill) Bernh. provavelmente está associada à variabilidade genética existente entre as diferentes linhagens de uma mesma espécie e das diferentes espécies, sendo que concentrações inferiores a 12,5 mg mL-1 não apresentaram efeito sobre as leveduras testadas. Com base na metodologia empregada e dentro das limitações deste estudo, conclui-se que o extrato aquoso de A. minus revelou efeito antifúngico, principalmente fungistático, contra espécies de Candida orais. Porém, novos estudos são necessários para avaliar o seu real potencial antifúngico dentro do meio bucal.

This study aimed to evaluate the antifungal activity of the aqueous extract from leaves of burdock [Arctium minus (Hill) Bernh.] by determining the Minimum Inhibitory Concentration (MIC) and the Minimum Fungicidal Concentration (MFC) on different species and strains of Candida genus. The species Candida albicans, C. tropicalis, C. glabrata, C. stellatoidea, C. dubliniensis, and C. Krusei were included in this study. Four C. albicans and three C. tropicalis strains were used, whereas only one strain of each remaining species was tested. Such yeasts were used in this study due to their importance and frequency in the oral cavity. The yeasts were subjected to treatments with aqueous extract concentrations that ranged from 0.09 to 25 mg mL-1. Concentrations lower than 12.5 mg mL-1 were not enough to present fungicidal or fungistatic effect. The concentration of 12.5 mg mL-1 had fungistatic effect on most tested strains and species (C. albicans 04A and ATCC44858; C. tropicalis 23600 and 23651; C. glabrata; C. stellatoideia; C. dubliniensis; and C. krusei). However, fungicidal effect was only observed on the species C. krusei (MFC=12.5 mg mL-1). A distinct performance was observed among different strains from the same species (for C. albicans and C. tropicalis). Thus, the antifungal action of A. minus (Hill) Bernh. aqueous extract is probably associated with the genetic variability present among the different strains of one same species and among different species; besides, concentrations lower than 12,5 mg mL-1 did not have an effect on the tested yeasts. The adopted methodology and considering the limitations of this study led to the conclusion that the aqueous extract of A. minus presented antifungal effect, mainly fungistatic, against oral Candida species. However, new studies are needed to evaluate its real antifungal potential inside the oral environment.

Clinical performance and wear resistance of two compomers in posterior occlusal restorations of permanent teeth: six-year follow-up.

This study evaluated the clinical performance and wear resistance of compomer restorations placed in the occlusal cavities of posterior permanent teeth after six years. In 1999, 72 Class I restorations were placed by a single operator in 33 patients. Eighty-two percent of these restorations were located in molars. Each patient received at least two restorations, one with F2000 (3M ESPE) and another with Dyract AP (Dentsply). The finished and polished restorations that were free of any failure were considered the baseline. The restorations were clinically evaluated at baseline and at one-, two- and six-year intervals using modified USPHS criteria for color mismatch, marginal discoloration, surface roughness, marginal adaptation, anatomic form and secondary caries. Polyvinylsiloxane impressions (Express, 3M ESPE) were also taken, and models were obtained for indirect wear assessment (Leinfelder scale) at the same intervals. After six years, 11 patients attended the recall. Twenty-seven compomer restorations (11 with Dyract and 16 with F2000) were reevaluated. Data were submitted to the Friedman's test, ANOVA with repetitive measures, Tukey's test (clinical data), Wilcoxon and Kruskal-Wallis tests and the Spearman's correlation test (wear evaluation), all at a significance level of p < 0.05. When comparing the materials, F2000 and Dyract presented similar clinical performance and occlusal wear at the end of the clinical trial. The two compomers showed a significant increase in wear at the six-year follow-up, and a positive correlation (r2 = 0.65) was detected between wear and evaluation time (p < 0.001). Despite the decrease in restoration quality and the increase in occlusal wear, nearly all restorations were considered acceptable after the six-year evaluation.

Dissolving efficacy of organic solvents on root canal sealers.

The aim of this study was to evaluate the solubility of three types of root canal sealers in three organic solvents used in endodontics. The solubility of calcium-hydroxide-based (Sealer 26), silicon-polydimethylsiloxane-based (RoekoSeal), and zinc-oxide-eugenol based (Endofill and Intrafill) sealers was assessed in eucalyptol, xylol, orange oil, and distilled water. Eighty samples of each filling material were prepared according to the manufacturers' instructions and then divided into four groups for immersion in solvent for 2 or 10 min. The means of sealer dissolution in solvents were obtained by the difference between the original preimmersion weight and the postimmersion weight in a digital analytical scale. Data were statistically analyzed with the Student's t test, and multiple comparisons were performed with Student-Newman-Keuls. Xylol and orange oil showed similar effects, with significant solubilization (P<0.05) of the tested cements. Endofill and Sealer 26 did not show any significant difference in solubilization at the two immersion times, whereas RoekoSeal and Intrafill showed a more pronounced solubility at 10 min. The lowest levels of solubilization occurred in RoekoSeal, Sealer 26, Endofill, and Intrafill. It is concluded that xylol and orange oil presented similar solvent effects with a significant solubility of the tested cements.