Determining growth inhibition of Candida albicans biofilm on denture materials after application of an organoselenium-containing dental sealant.

STATEMENT OF PROBLEM: Denture stomatitis is a chronic inflammatory condition caused by the formation of Candida albicans biofilm on denture bases. It is associated with aggravating intraoral pain, itching, and burning sensations. It can also potentiate cardiovascular diseases and aspiration pneumonia. The problem has thus far eluded efficient, toxic-free, and cost-effective solutions. PURPOSE: The purpose of this in vitro study was to investigate the effectiveness of organoselenium to inhibit the formation of C. albicans biofilm on the surface of acrylic resin denture base materials when it is either incorporated into the acrylic resin material or coated on the denture surface as a light-polymerized surface sealant. MATERIAL AND METHODS: Sixty heat-polymerized polymethyl methacrylate disks were fabricated and assigned to 4 groups (n=15): disks coated with a light-polymerized organoselenium-containing enamel surface sealant (DenteShield), disks impregnated with 0.5% organoselenium (0.5% selenium), disks impregnated with 1% organoselenium (1% selenium), and disks without organoselenium (control). C. albicans biofilm was grown on each disk which had been placed in a well of the microtiter plate containing 1-mL brain heart infusion broth inoculated with C. albicans. The plates were incubated aerobically at 37 °C for 48 hours. A confocal laser scanning microscope was used to determine the biofilm thickness, biomass, and live/dead cell ratio. Biofilm morphology was examined with scanning electron microscopy, whereas microbial viability was quantified by the spread plate method. The data were analyzed by using ANOVA and Tukey-Kramer multiple comparisons (α=.05). RESULTS: The microbial viability, biofilm thickness, biofilm biomass, and live/dead cell ratio were lower (P<.001) on disks in the test groups (DenteShield, 0.5% selenium, 1% selenium) when compared with the control group, with these variables being lowest in the 0.5% selenium and 1% selenium groups. The 0.5% selenium and 1% selenium groups did not differ significantly from each other in any of the variables (P>.05). Scanning electron microscope images showed inhibition of both biofilm growth and yeast to hyphae transition in the DenteShield, 0.5% selenium, and 1% selenium groups, with visible disruption of the biofilm morphology. CONCLUSIONS: The present study demonstrated that organoselenium, whether incorporated into or coated on the surface of an acrylic resin denture base material, has the potential to inhibit Candida albicans biofilm growth on denture surfaces and as such can be clinically useful for the prevention of denture stomatitis.

Effect of sodium hypochlorite and Ricinus communis solutions on control of denture biofilm: A randomized crossover clinical trial.

STATEMENT OF PROBLEM: The prevalence of complete edentulism remains high in the elderly, and previous data have shown that poor denture hygiene is common among patients with edentulism. PURPOSE: The purpose of this randomized crossover trial was to evaluate the efficacy of denture cleansers in terms of biofilm removal, antimicrobial action, and the remission of denture stomatitis. MATERIAL AND METHODS: Fifty denture wearers with denture stomatitis were instructed to brush their dentures (brush and soap) and to soak them (20 minutes/14 days) in 4 solutions, as follows: C (control), 0.85% saline; SH1, 0.1% sodium hypochlorite; SH2, 0.2% sodium hypochlorite; and RC, 8% Ricinus communis. The biofilm in the intaglio surface of maxillary dentures was stained, photographed, and quantified by software (Image Tool). It was then collected (brushed with saline solution), and the obtained suspension was diluted (100 to 10-3) and seeded (50 µL) in CHROMagar for Candida spp. After incubation, colony-forming units per milliliter values were calculated. Denture stomatitis remission was classified according to the Newton classification. Data were analyzed by Friedman (α=.05) and Wilcoxon tests and corrected by the Bonferroni test (α=.005). RESULTS: SH1 (mean rank [MR]=1.98) and SH2 (MR=1.64) showed lower biofilm coverage than C (MR=3.73) that was similar to RC (MR=2.92). SH1 (MR=2.43) and SH2 (MR=2.10) showed antimicrobial action for Candida spp, and RC (MR=3.36) showed similar results to C (MR=3.51) and baseline (MR=3.50). Clinical signs of denture stomatitis were reduced by SH1 (MR=2.44), while SH2 (MR=2.56) and RC (MR=2.74) showed intermediate results. CONCLUSIONS: The two sodium hypochlorite solutions were the most effective means of biofilm control. All tested solutions were effective in reducing the signs of denture stomatitis.

[PHYSICAL AND MATHEMATICAL GROUNDS LANDFORMS BASIS PLATE DENTURES WHEN APPLYING THE COMPLEX METHOD OF PREVENTION OF PROSTHETIC STOMATITIS].

Objective - to develop the form of the drug reservoir to hold the vegetable oils under the basis of the prosthesis. The research was conducted on the Bench PMMA samples. The comparison group consisted of smooth plate PMMA. Two study groups were PMMA plates with grooves on one side of a square with sides of 2 mm and depth of channel - 1 mm. The third group consisted of the experimental plate with diamond-shaped notches with the same parameters. The lowest value of the stress in the plate having a rhombic grid, they are 54% less than in the smooth plate and 37% less than in the plate with a square lattice (the best strength characteristics in a rhombic plate with grille). Equivalent move from the plate with a rhombic lattice is less than an order of magnitude than that of a smooth plate and by 5.8% more than at the plate with a square lattice, which indicates good performance design plasticity with rhombic grid. Basis with the rhombic lattice on the surface has the best record on the stress-strain state in comparison with other models considered (smooth plate with a square lattice plate).

Fabrication and Evaluation of Nanostructured Herbal Oil/Hydroxypropyl-ß-Cyclodextrin/Polyvinylpyrrolidone Mats for Denture Stomatitis Prevention and Treatment.

This work aims to develop the herbal oil-incorporated nanostructure mats with antifungal activity for the prevention and treatment of Candida-associated denture stomatitis. The nanofiber mats loaded with betel oil or clove oil were fabricated via electrospinning process. The morphologies and physicochemical properties of the herbal oil loaded nanofiber mats were examined using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), and mechanical testing. The release characteristic, antifungal activity, and cytotoxicity were also investigated. The SEM images confirmed the homogeneous and smooth nanoscale fibers. The addition of the herbal oil into the nanofiber mats reduced the fiber diameters. The DSC and FT-IR results confirmed the presence of the oil in the nanofiber mats. The herbal oils can be released from the mats in a very fast manner and inhibit the growth of candida cells within only few minutes after contact. These nanofiber mats may be beneficial for the prevention and treatment of denture stomatitis.

Influence of melaleuca and copaiba oils on Candida albicans adhesion.

OBJECTIVE: To evaluate the efficacy of Melaleuca alternifolia and Copaifera officinalis in inhibiting the adhesion of Candida albicans biofilm. BACKGROUND: Over 65% of denture wearers suffer from denture stomatitis, which is one of the most prevalent forms of oral candidiasis. This disease is characterised by the inflammation of the oral mucosa in contact with the contaminated denture. The contaminated denture contributes to the switch of C. albicans from yeast to its pathogenic hyphal form. Candida albicans adheres and colonises the polymethylmethacrylate resin surfaces and thus contributes to the development of denture stomatitis. MATERIALS AND METHODS: The minimal inhibitory concentration (MIC) of M. alternifolia and Co. officinalis was assessed by the agar dilution method. Sixty-six thermopolymerised acrylic resin squares were used and treated with phosphate-buffered saline, sodium hypochlorite 1%, melaleuca 0.75%, melaleuca 0.375%, melaleuca 0.188% and copaiba 10%. For adherence and biofilm formation, the treated squares were placed in six-well tissue culture plates containing 1 × 10(7)  cells/ml of ATCC1023 or SC5314 in Roswell Park Memorial Institute (RPMI) medium, and after 12 h, the planktonic cells were counted. RESULTS: Copaiba oil did not inhibit C. albicans growth. However, melaleuca oil showed an MIC value of 0.375% (3.4 mg/ml) for ATCC10231 and 0.093% (0.84 mg/ml) for SC5314. CONCLUSIONS: Our results demonstrated that M. alternifolia oil inhibited the growth of C. albicans. Moreover, both oils promoted significant adhesion reduction in the tested strains. These findings suggest the possibility of using these oils in prophylaxes against candidiasis.

Equisetum giganteum e Punica granatum Linné associados a adesivo protético: atividade antimicrobiana contra biofilmes de Candida albicans / Equisetum giganteum and Punica granatum Linn associated with denture adhesive: antimicrobial activity against Candida albicans biofilms

Adesivos protéticos inibem a inflamação da mucosa subjacente e podem receber, em sua composição, componentes antimicrobianos, reduzindo o risco do desenvolvimento da estomatite protética (EP), doença relacionada principalmente à colonização das próteses pelo fungo Candida albicans. Tem sido relatada a atividade antifúngica de fitoterápicos, podendo auxiliar no tratamento da EP. Objetivo: Realizar o estudo fitoquímico de substâncias potencialmente ativas de Equisetum giganteum (Eg) (Cavalinha) e de Punica granatum (Pg) (Romã) e avaliar in vitro se a incorporação de extratos hidroalcóolicos de Eg e de Pg a um adesivo protético (COREGA®) influencia no desenvolvimento do biofilme de C. albicans (SC5314) sobre a superfície de resina acrílica termopolimerizável (Lucitone 550). Material e Métodos: Após identificação dos compostos dos fitoterápicos por HPLC-PAD, foi selecionada a fração e a concentração de interesse por meio da concentração inibitória mínima (CIM). Os biofilmes foram induzidos durante 3, 6 ou 12 horas sobre a superfície de corpos de prova de resina acrílica, previamente submetidos ao tratamento com o adesivo associado aos fitoterápicos (AD/Eg ou AD/Pg). Como controles, corpos de prova foram tratados apenas com adesivo (AD), com a associação adesivo/nistatina (AD/Nt) ou não recebam tratamento (PBS). A atividade antimicrobiana foi avaliada por meio da quantificação do biofilme pela contagem de unidades formadoras de colônias por mililitro (UFC/mL) e pelo percentual de redução da atividade metabólica das células fúngicas pelo ensaio colorimétrico de redução de sais de tetrazólio XTT (2,3 Bis (2-Methoxy-4-Nitro-5-Sulfophenil) 5 - [(Phenyl-Amino) Carbonyl] 2H - Tetrazolium Hidroxide). Os resultados foram expressos como média ± desvio padrão, e submetidos ao teste de Kruskal-Wallis para UFC/mL e Mann-Whitney ou análise de variância ANOVA-2 fatores seguido do teste post-hoc de Tukey HSD e teste de Dunnett para XTT. As médias dos valores obtidos pelas duas metodologias (UFC/mL e XTT) foram submetidas ao teste de correlação de Spearman (α= 0,05). Resultados: Foi possível identificar, pela análise em HPLCPAD, compostos derivados de kaempferol e quercetina em Eg e derivados de elagitaninos, como punicalina, em Pg. A associação de ambos os fitoterápicos ao adesivo (AD/Eg ou AD/Pg) reduziram significativamente o biofilme sobre a superfície da resina, em comparação ao grupo AD. Considerando os corpos de prova tratados, o período inicial (3 horas) apresentou os melhores resultados em relação à inibição do crescimento fúngico, comparando-se com os outros períodos. Conclusão: Possivelmente, o potencial antimicrobiano de Eg e de Pg está associado a compostos como flavonoides e taninos, respectivamente. Por fim, é possível que a associação destes fitoterápicos ao adesivo protético COREGA® poderá constituir uma alternativa temporária, viável e inovadora para auxiliar no tratamento e/ou prevenção da EP, desde que a manutenção das propriedades inerentes deste adesivo seja comprovada após estudos posteriores.(AU)

Denture adhesives inhibit inflammation of the underlying mucosal tissue and can receive, in their composition, antimicrobial components, reducing the risk of development of denture stomatitis (DS), a disease related mainly to the colonization of the prosthesis by the fungus Candida albicans. It has been reported the antifungal activity of herbal medicines, which may help in the treatment of DS. Objective: To realize the phytochemical study of potentially active substances of Equisetum giganteum (Eg) (Cola de caballo) and Punica granatum Linne (Pg) (Pomegranate) and evaluate in vitro the incorporation of hydroalcoholic extracts of Eg and Pg to a denture adhesive (COREGA®) influences the development C. albicans biofilm (SC5314) on the surface a polymerized acrylic resin (Lucitone 550). Material and Methods: After identification of compounds of the herbal by HPLC-PAD, the fraction and the concentration were selected by minimum inhibitory concentration (MIC). Biofilms were induced for 3, 6 or 12 hours on the surface of acrylic resin specimens, previously subjected to treatment with the adhesive associated with herbal (AD/Eg or AD/Pg). As controls, samples were treated with adhesive (AD), adhesive/nystatin association (AD/Nt) or not received treatment (PBS). The antimicrobial activity was evaluated by quantifying the biofilm using counting colony forming units per milliliter (CFU/mL) and by reduction percentage of fungal metabolic activity using colorimetric assay XTT (2,3 Bis (2-Methoxy-4-Nitro-5-Sulfophenil) 5 - [(Phenyl-Amino) Carbonyl] 2H - Tetrazolium Hidroxide). The results were expressed as mean ± standard deviation, and subjected to Kruscal-Wallis test for CFU/mL and Mann-Whitney or 2-way analysis of variance (ANOVA) followed by Tukey's HSD post-hoc test and Dunnett test for XTT. The mean values obtained by the two methods (CFU/mL and XTT) were submitted to Spearman correlation test (α=0,05). Results: It was possible to identify, by the analysis on HPLC-PAD, compounds derived from kaempferol and quercetin in Eg and ellagitannins derivatives, as punicalin in Pg. The combination of both herbal medicines to the adhesive (AD/Eg or AD/Pg) significantly reduced the biofilm on the surface of the resin, compared to the AD group. Accordingly, there was an increase in the percentage of reduction of the metabolic activity of biofilm at all periods in the presence of herbal medicines. Considering the treated specimens, the initial period (3 hours) showed the best results in relation to inhibition of fungal growth compared with other periods. Conclusion: Possibly, the antimicrobial potential of E. giganteum and P. granatum is associated with compounds such as flavonoids and tannins, respectively. Finally, we suggest that the combination of these herbal medicines to COREGA® prosthetic adhesive may be a temporary, viable and innovative alternative to assist in the treatment and/or prevention of DS, since the maintenance of the inherent properties of this adhesive is proven after further studies.(AU)

Inhibitory effect of Streblus asper leaf-extract on adhesion of Candida albicans to denture acrylic.

This in vitro study aimed at determining the effects of various sublethal concentrations of Streblus asper leaf ethanolic extract (SAE) on adherence of Candida albicans to acrylic surface. A colorimetric tetrazolium assay using (2,3)-bis (2-methoxy-4-nitro-5-sulfophenyl)-5-[(phenylamino)-carbonyl]-2H-tetrazolium hydroxide was used to make the quantitative determination. The SAE at a concentration equivalent to nystatin (6.24microg/ml) pinpointed the minimal exposure time of SAE in suppressing candidal adhesion to acrylic. Adhesion of Candida albicans to acrylic was determined after exposure to SAE for 1, 15, 30, 60, 120 and 180min. The minimum concentration of SAE that significantly reduced adherence (P<0.05) after a 4-h exposure was 31.25mg/ml. In addition, a significant reduction (P<0.01) of candidal adhesion to acrylic occurred after a 1min exposure to 62.5mg/ml of SAE. Pre-treatment of yeast with 62.5mg/ml of SAE for 1h before adhesion assay significant reduced the adherence as 20.54% compared to the untreated control, whereas the same treatment with acrylic strips did not show any effect. These findings indicate that exposure of Candida albicans to sublethal concentrations of SAE results in a reduction in the ability of the yeasts to adhere to denture acrylic, possibly preventative of denture stomatitis.

[Efficacy of treating denture-induced stomatitis by electrically activated aqueous solutions]. / Effektivnost' lecheniia "proteznogo stomatita" élektroaktivirovannymi vodnymi rastvorami.

The authors investigated the oral mucosa in 35 patients, who were divided into four groups: Group 1 (n = 17) received traditional treatment, Group 1 (n = 18) had the similar treatment supplemented by electrically activated aqueous calcium chloride solutions. The findings have shown that the use of electrically activated aqueous calcium chloride solutions in the complex treatment of orthopaedic stomatitis exert more marked clinical and immunological effects than the traditional treatment (p < 0.001-0.01).

Microwave disinfection of denture base materials colonized with Candida albicans.

STATEMENT OF PROBLEM: Infection of denture materials with Candida albicans is common and contributes to denture stomatitis. PURPOSE: This 3-phase investigation examined: (1) the efficacy of microwave irradiation against C albicans colonized on 3 soft denture liners and 1 heat-polymerized denture base resin, and (2) the effect of this irradiation on the hardness of the materials tested. MATERIAL AND METHODS: In phase 1, an experimental protocol was developed. Sterilized specimens from 2 denture base soft liners and 1 heat-polymerized acrylic resin denture base material (n = 45 each) were inoculated with C albicans. Two thirds of the specimens were irradiated in a 60 Hz microwave oven for 5 minutes (dry). C albicans growth was then assessed with streaked blood agar plates and thioglycollate broth. One third of the specimens were not irradiated and served as controls. Pretest and posttest Shore A hardness values were obtained and compared. For phase 2, 15 specimens from each material group were subjected to irradiation (while immersed in water) for 5 minutes; and, 15 from each material were subjected to 10- and 15-minute irradiation (dry), with subsequent sterility and change in hardness assessments completed as described in phase 1. In phase 3, 15 specimens from each material group were subjected to repeated 5-minute irradiation cycles (while immersed in water), and changes in hardness were examined. RESULTS: Only the 5-minute irradiated specimens immersed in water were effectively sterilized, as verified by the thioglycollate assay. The effect of repeated 5-minute irradiation cycles resulted in a significant change in hardness of the PermaSoft specimens. CONCLUSIONS: Five-minute irradiation, while immersed in water, killed all C albicans present on the materials tested; and, repeated 5-minute irradiation significantly affected the hardness of only the PermaSoft material.