Adherence Of Candida Albicans Research Articles

Candida albicans Adhesion Measured by Optical Nanomotion Detection

Cellular adhesion plays an important role in numerous fundamental physiological and pathological processes. Its measurement is relatively complex, requires sophisticated equipment, and, in most cases, cannot be carried out without breaking the links between the studied cell and its target. In this contribution, we propose a novel, nanomotion-based, technique that overcomes these drawbacks. The applied force is generated by the studied cell itself (nanomotion), whereas cellular movements are detected by traditional optical microscopy and dedicated software. The measurement is non-destructive, single-cell sensitive, and permits following the evolution of the adhesion as a function of time. We applied the technique on different strains of the fungal pathogen Candida albicans on a fibronectin-coated surface. We demonstrated that this novel approach can significantly simplify, accelerate, and make more affordable living cells–substrate adhesion measurements.

Colonization resistance of buccal epitheliocytes as an indicator of mucosal immune homeostatic resources in children with recurrent respiratory diseases

Of particular interest is the study of colonization resistance of the oral cavity as a physiological phenomenon that reflects the ability of the microbiota and macroorganism in cooperation to protect the ecosystem of the oral cavity from pathogens. Purpose is to evaluate the significance of indicators of colonization resistance of buccal epithelial cells as a marker of homeostatic resources of mucosal immunity in recurrent respiratory diseases in children. Material and methods. 232 (5–16 years old) children were examined, including 56 children with acute bronchitis, 73 with recurrent bronchitis, 103 with community-acquired pneumonia. The control group included 31 apparently healthy children of the same age and sex. Used: conventional paraclinical and laboratory-instrumental methods, etiological verification of viruses and bacteria, colonization index and artificial colonization of buccal epitheliocytes, antiadhesive activity of saliva. Results. 64.38% of children with recurrent bronchitis and 72.82% of children with community-acquired pneumonia were born from an aggravated pregnancy and already at 3 months had signs of acute respiratory diseases. Viral antigens were detected in 63.36% of children. An inverse relationship was found between the indicators of artificial colonization and adhesion of Candida albicans on buccal epithelial cells — the lower the values of artificial colonization, the more often pneumonia and recurrent bronchitis were recorded. A significant decrease in saliva antiadhesion was found in recurrent bronchitis and community-acquired pneumonia, significantly different not only from the control, but also from patients with acute bronchitis. This contingent of patients finds itself in extremely unfavorable conditions due to the disruption of the adaptive reserves of the mucosal defense of the body. Conclusion. A decrease in the index of colonization, antiadhesive activity of saliva against the background of increasing parameters of artificial colonization in children with recurrent bronchitis and community-acquired pneumonia indicate deep dysbiosis. The high significance of screening approaches in assessing the homeostatic resources of mucosal protection of the oral cavity in children with bronchopulmonary pathology has been proven.

Comparative Evaluation of Surface Roughness and Adhesion of Candida albicans on Conventional Heat-cured, Injection-molded Thermoplastic Resin and CAD-CAM Denture Base Resin as Affected by Denture Cleanser: An In Vitro Study

Comparative Evaluation of Surface Roughness and Adhesion of Candida albicans on Conventional Heat-cured, Injection-molded Thermoplastic Resin and CAD-CAM Denture Base Resin as Affected by Denture Cleanser: An In Vitro Study

Konvansiyonel, CAD/CAM frezeleme ve 3D baskı yöntemleriyle üretilmiş geçici materyallerin yüzey özelliklerinin Streptococcus mutans ve Candida albicans tutunumuna etkileri

Objectives: The purpose of this in vitro study was to compare conventionally manufactured, CAD/CAM milled, and 3D-printed interim materials based on their susceptibility to adherence of Streptococcus mutans and Candida albicans, and examine the influence of surface roughness and hydrophobicity. Materials and Methods: Eighty disc-shaped specimens fabricated from autopolymerized polymethyl methacrylate (A-PMMA), bis-acryl composite (Bis-acrylate), CAD/CAM PMMA-based polymer (Milled-PMMA), and 3D-printed resin (Printed) were subjected to 10,000 thermal cycles (5-55 °C) and divided into two groups (n=10) according to microbial suspension used: Streptococcus mutans and Candida albicans. Surface roughness (Ra) and hydrophobicity (WCA) of specimens were measured. An adhesion test was performed by incubating the specimens in Streptococcus mutans and Candida albicans suspensions at 37 °C for 24 hours, and the adherent cells were evaluated by counting colony-forming units (CFU/ml). Scanning electron microscopy (SEM) was performed to analyze the surfaces (n=2). Data were analyzed with Kruskal-Wallis and Mann-Whitney U tests. Spearman’s correlation analysis was used to determine correlation among the measurements (α=.05). Results: Type of restorative material significantly influenced Ra and WCA. The highest adhesion of Streptococcus mutans was observed in Printed, followed by Bis-acrylate, A-PMMA, and Milled-PMMA (p=.001). The highest adhesion of Candida albicans was noted on A-PMMA, followed by Printed, Bis-acrylate, and Milled-PMMA (r=.001). The adhesion of Streptococcus mutans (r=.660) and Candida albicans (r=.413) showed a positive correlation with Ra. A negative correlation was found between WCA of the materials and Streptococcus mutans adhesion (r=-.373). Conclusions: Surface roughness plays an important role in the adherence of microorganisms. CAD/CAM PMMA-based polymers may be a better choice to reduce microbial adhesion in long-term use.

The influence of lemongrass essential oil addition into heat cured acrylic resin against Candida albicans adhesion

Background: For decades, the use of naturally accessible materials in treating human disease has been widespread. The goal of this study was to determine the anti-fungal effectiveness /of the lemongrass essential oil (LGEO) versus Candida albicans (C. albicans) adhesion to polymethylmethacrylate (PMMA) materials. Material and methods: LGEO's anti-fungal activity was tested against C. albicans adhesion using the following concentration of LGEO in PMMA monomer (2.5 vol. %, 5 vol. % LGEO) selected from the pilot study as the best two effective concentrations. A total of 40 specimens were fabricated for the candida adherence test and were subdivided into four equal groups: negative control 0 vol. % addition, experimental with 2.5 vol. % and 5 vol. % of LGEO addition and positive control with 1.4 wt. % nystatin addition. The sterile PMMA specimens were incubated at room temperature for 1 hr in sterile tubes with a sabouraud dextrose broth (SDA) in which a small amount of the yeast was isolated and suspended; under the inverted light microscope, the examination was done. The data were evaluated using a one-way ANOVA test, which showed a significant result at p< 0.05. Results: The findings of the C. albicans adherence test exposed a considerable reduction in the number of C. albicans cells adhering to PMMA after adding 2.5 vol. % and 5 vol. % LGEO compared to specimens from the negative control and positive control groups at p< 0.05. Conclusion: Adding LGEO into a heat-cure acrylic material can result in a denture base material with anti-fungal properties versus C. albicans microorganisms. The experimental group 5 vol. % LGEO additive showed the best anti-fungal activity

Oral microbial colonization on titanium and polyetheretherketone dental implant healing abutments: An in vitro and in vivo study

Although polyetheretherketone (PEEK) implant healing abutments have become popular because of their esthetic, mechanical, and chemical properties, studies analyzing oral polymicrobial adhesion to PEEK abutments are lacking. The purpose of this in vitro and in vivo study was to evaluate oral microbial adhesion and colonization on titanium (Ti) and PEEK healing abutments. Ti (N=35) and PEEK substrates (N=35) were evaluated in vitro in terms of the initial adhesion (1 hour) or biofilm accumulation (48 hours) of Candida albicans and a polymicrobial inoculum using stimulated human saliva to mimic a diverse oral microbiome. Surface decontamination ability was evaluated after 24 hours of in vitro biofilm formation after exposure to an erbium-doped yttrium aluminum garnet (Er:YAG) laser. Conventional and flowable composite resin veneering on PEEK was also tested for microbial adhesion. In addition, an in vivo model with 3 healthy volunteers was conducted by using a palatal appliance containing the tested materials (3 or 4 specimens of each material per appliance) for 2 days to evaluate the effect of substrate on the microbial profile. Biofilms were evaluated by live cell counts and scanning electron microscopy images, and the microbial profile by Checkerboard deoxyribonucleic acid (DNA)-DNA hybridization. The t test and Mann-Whitney test were used to compare the groups (α=.05). PEEK and Ti materials showed similar fungal adhesion (P>.05). Although the PEEK surface limited the initial in vitro polymicrobial adhesion (approximately 2 times less) compared with Ti (P=.040), after 48 hours of biofilm accumulation, the microbial load was statistically similar (P=.209). Er:YAG laser decontamination was more effective on PEEK than on Ti surfaces, reducing approximately 11 times more microbial accumulation (P=.019). Both composite resins tested showed similar microbial adhesion (1 hour). In vivo, the PEEK material showed reduced levels of 6 bacterial species (P<.05), including the putative pathogen Treponema denticola. Although PEEK and Ti had similar bacterial and fungus biofilm attachment and accumulation, PEEK promoted a host-compatible microbial profile with a significantly reduced T. denticola load.

In Vitro Evaluation of Candida albicans Adhesion on Heat-Cured Resin-Based Dental Composites.

Microbial adhesion on dental restorative materials may jeopardize the restorative treatment long-term outcome. The goal of this in vitro study was to assess Candida albicans capability to adhere and form a biofilm on the surface of heat-cured dental composites having different formulations but subjected to identical surface treatments and polymerization protocols. Three commercially available composites were evaluated: GrandioSO (GR), Venus Diamond (VD) and Enamel Plus HRi Biofunction (BF). Cylindrical specimens were prepared for quantitative determination of C. albicans S5 planktonic CFU count, sessile cells CFU count and biomass optical density (OD570 nm). Qualitative Concanavalin-A assays (for extracellular polymeric substances of a biofilm matrix) and Scanning Electron Microscope (SEM) analyses (for the morphology of sessile colonies) were also performed. Focusing on planktonic CFU count, a slight but not significant reduction was observed with VD as compared to GR. Regarding sessile cells CFU count and biomass OD570 nm, a significant increase was observed for VD compared to GR and BF. Concanavalin-A assays and SEM analyses confirmed the quantitative results. Different formulations of commercially available resin composites may differently interact with C. albicans. The present results showed a relatively more pronounced antiadhesive effect for BF and GR, with a reduction in sessile cells CFU count and biomass quantification.

Antifungal effects of eugenol on Candida albicans adherence to denture polymers.

The study's objective is to assess the adherence of C. albicans in different types of denture polymers and the effectiveness of eugenol and commercialized denture cleansers in the removal of C. albicans. Three types of denture base polymers (Lucitone® 199 (High-Impact PMMA), Impact® (conventional PMMA) and Eclipse® (UDMA)) and two hard denture reline materials (Kooliner® and Tokuyama® Rebase II Fast) were used in this study. Three hundred samples were prepared (6 × 2 mm disc shape) and divided into five groups of denture polymers (n=60) and further subjected into five treatment groups (Polident®, Steradent, distilled water, eugenol 5-minutes, and eugenol 10-min). Three samples were extracted from each treatment group for baseline data (n=12). Baseline data were used to calculate the initial number of C. albicans adherence. A 0.5 ml immersion solution from each specimen was cultured on YPD agar and incubated for 48 h at 37 °C. Visible colonies were counted using a colony counter machine (ROCKER Galaxy 230). The result showed that the denture base polymer significantly affected the initial adherence (p=0.007). The removal of C. albicans was also considerably affected by the denture base polymers and denture cleansers (p<0.05). Lucitone®, Tokuyama®, and Kooliner® denture base polymers immersed for 3 min in eugenol showed the best results of removal. This study's overall results showed that all denture polymers used as denture bases had an effect on C. albicans initial adherence and removal from the denture base, and eugenol is comparable to commercialised denture cleansers in reducing the number of attached C. albicans on denture base polymers.

Candida albicans adherence on soft denture liner coated with silica and titanium nanoparticles

Candida albicans adherence on soft denture liner coated with silica and titanium nanoparticles

Antifungal Effect of Polymethyl Methacrylate Resin Base with Embedded Au Nanoparticles.

Full and partial restorations in dentistry must replicate the characteristics of the patient's natural teeth. Materials must have good mechanical properties and be non-toxic and biocompatible. Microbes, which can form biofilms, are constantly in contact with restorations. In this study, we investigate how well Candida albicans adheres to a polymethyl methacrylate (PMMA) resin base with gold (Au) nanoparticles. We synthesized Au nanoparticles and characterized them. The average size of Au nanoparticles embedded in PMMA was 11 nm. The color difference ΔE between PMMA and PMMA/Au composites was 2.7 and was still esthetically acceptable to patients. PMMA/Au surfaces are smoother and more hydrophilic than pure PMMA surfaces, and the isoelectric point of both types of surfaces was 4.3. Above the isoelectric point, PMMA/Au surfaces are more negatively charged than PMMA surfaces. The added Au nanoparticles decreased the tensile strength, while the hardness did not change significantly. Adhesion measurements showed that PMMA surfaces modified with Au nanoparticles reduced the extent of microbial adhesion of Candida albicans.

An in vitro study on comparative adherence of oral Candida albicans and non–albicans Candida to human buccal epithelial cells and its antifungal susceptibility pattern

Background: Candida spp. are intra-oral commensals in 40-60% of human subjects and the precise factors involved in the development of Candidiasis are still not clear. The adherence of Candida to epithelial cells is one of the main pathogenic characteristics of the genus. Studies have shown that there are variations in the adherence capabilities of different Candida spp., which may explain why some species colonize mucosal surfaces more frequently than others. The aim of this study was to estimate the adherence properties of Candida spp. to buccal epithelial cells and to determine the antifungal susceptibility. Methods: 87 isolates of Candida spp. from known non-diabetic patients with oral Candidiasis were collected from diagnostic microbiology laboratories in central Kerala. The method of Kimura and Pearsall et al was followed with minor modifications to test the adherence. Results: All the three species exhibited adherence with varying capacity. C. albicans was significantly more adherent to buccal epithelial cells than C. tropicalis and C. krusei. Resistance was not observed among the isolates against fluconazole, voriconazole and clotrimazole. Conclusions: In conclusion Candida spp. isolated from oral candidiasis patients exhibited a higher adherence capacity to normal human buccal epithelial cells considered an essential virulence property. As anticipated C. albicans displayed higher virulence activity than non-Candida albicans species.

Influence of Fabrication Technique on Adhesion and Biofilm Formation of Candida albicans to Conventional, Milled, and 3D-Printed Denture Base Resin Materials: A Comparative In Vitro Study.

The aim of this study was to evaluate the adhesion and biofilm formation of Candida albicans (C. albicans) on conventionally fabricated, milled, and 3D-printed denture base resin materials in order to determine the susceptibility of denture contamination during clinical use. Specimens were incubated with C. albicans (ATCC 10231) for 1 and 24 h. Adhesion and biofilm formation of C. albicans were assessed using the field emission scanning electron microscopy (FESEM). The XTT (2,3-(2-methoxy-4-nitro-5-sulphophenyl)-5-[(phenylamino) carbonyl]-2H-tetrazolium hydroxide) assay was used for the quantification of fungal adhesion and biofilm formation. The data were analyzed using GraphPad Prism 8.02 for windows. One-way ANOVA with Tukey's post hoc testing were performed with a statistical significance level set at α = 0.05. The quantitative XTT biofilm assay revealed significant differences in the biofilm formation of C. albicans between the three groups in the 24 h incubation period. The highest proportion of biofilm formation was observed in the 3D-printed group, followed by the conventional group, while the lowest candida biofilm formation was observed in the milled group. The difference in biofilm formation among the three tested dentures was statistically significant (p < 0.001). The manufacturing technique has an influence on the surface topography and microbiological properties of the fabricated denture base resin material. Additive 3D-printing technology results in increased candida adhesion and the roughest surface topography of maxillary resin denture base as compared to conventional flask compression and CAD/CAM milling techniques. In a clinical setting, patients wearing additively manufactured maxillary complete dentures are thus more susceptible to the development of candida-associated denture stomatitis and accordingly, strict oral hygiene measures and maintenance programs should be emphasized to patients.

Syzygium aromaticum extracts debilitate Candida albicans by radically inhibiting its morphological plasticity and biofilm formation

ABSTRACT The effects of Syzygium aromaticum extracts on the growth, germ tube production, biofilm formation and adhesion of Candida albicans to human buccal epithelial cells (BEC) were investigated. We found larger zones of inhibition of growth of C. albicans with the essential oil (EO) and methanolic extract (ME) than amphotericin B. Similarly, the MIC values for the EO and ME were lower than that of amphotericin B. The EO and ME caused greater reductions in biofilm formation than amphotericin-B. Pre-treatment of C. albicans and BEC with the EO caused greater reductions in adhesion to BEC than amphotericin B.

The Effect of Controlled Diabetic and Non-diabetic Saliva on Candida albicans Adherence to Heat Polymerized Acrylic Resin Discs

Background: Oral candidiasis is one of the most common infections in diabetic patients that may occur due to a decrease in salivary flow rate, alterations in the salivary composition, or both. This study aimed to investigate the effect of diabetic and non-diabetic saliva on Candida albicans adherence to the acrylic resin disc specimens, regardless of saliva volume. Methods: In this case-control study, the population consisted of 26 subjects in 2 groups (13 diabetic patients and 13 non-diabetic patients). In both groups, unstimulated whole saliva was collected. It was investigated for pH, salivary flow rate, and adhesion of C. albicans to polymethylmethacrylate disc. After preparing the polymethylmethacrylate discs, the samples were stored in diabetic saliva, non-diabetic saliva, and distilled water (negative control group) for 60 minutes at 37ºC. Then they were immersed in the yeast suspensions containing C. albicans and stained with gram stain. Yeast cells were counted using a light microscope. Results: The pH of unstimulated whole saliva in diabetic patients was significantly lower than in the control group. There was no significant difference between the flow rates of saliva in the two groups. Findings indicated that the adhesion of C. albicans to resin in diabetic saliva was higher than in non-diabetic saliva. Conclusion: This study showed the same amount of salivary flow rate in diabetic and non-diabetic individuals, lower pH, and higher Candida adherence to heat polymerization acrylic resin in the diabetic group.

Antibiofilm Activity of 3D-Printed Nanocomposite Resin: Impact of ZrO2 Nanoparticles.

Poly(methyl methacrylate) (PMMA) is a commonly used material, as it is biocompatible and relatively cheap. However, its mechanical properties and weak antibiofilm activity are major concerns. With the development of new technology, 3D-printed resins are emerging as replacements for PMMA. Few studies have investigated the antibiofilm activity of 3D-printed resins. Therefore, this study aimed to investigate the antibiofilm activity and surface roughness of a 3D-printed denture base resin modified with different concentrations of zirconium dioxide nanoparticles (ZrO2 NPs). A total of 60 resin disc specimens (15 × 2 mm) were fabricated and divided into six groups (n = 10). The groups comprised a heat-polymerized resin (PMMA) group, an unmodified 3D-printed resin (NextDent) group, and four 3D-printed resin groups that were modified with ZrO2 NPs at various concentrations (0.5 wt%, 1 wt%, 3 wt%, and 5 wt%). All specimens were polished using a conventional method and then placed in a thermocycler machine for 5000 cycles. Surface roughness (Ra, µm) was measured using a non-contact profilometer. The adhesion of Candida albicans (C. albicans) was measured using a fungal adhesion assay that consisted of a colony forming unit assay and a cell proliferation assay. The data were analyzed using Shapiro-Wilk and Kruskal-Wallis tests. A Mann-Whitney U test was used for pairwise comparison, and p-values of less than 0.05 were considered statistically significant. The lowest Ra value (0.88 ± 0.087 µm) was recorded for the PMMA group. In comparison to the PMMA group, the 3% ZrO2 NPs 3D-printed group showed a significant increase in Ra (p < 0.025). For the 3D-printed resins, significant differences were found between the groups with 0% vs. 3% ZrO2 NPs and 3% vs. 5% ZrO2 NPs (p < 0.025). The highest Ra value (0.96 ± 0.06 µm) was recorded for the 3% ZrO2 NPs group, and the lowest Ra values (0.91 ± 0.03 µm) were recorded for the 0.5% and 5% ZrO2 NPs groups. In terms of antifungal activity, the cell proliferation assay showed a significant decrease in the C. albicans count for the 0.5% ZrO2 NPs group when compared with PMMA and all other groups of 3D-printed resins. The group with the lowest concentration of ZrO2 NPs (0.5%) showed the lowest level of C. albicans adhesion of all the tested groups and showed the lowest Candida count (0.29 ± 0.03). The addition of ZrO2 NPs in low concentrations did not affect the surface roughness of the 3D-printed resins. These 3D-printed resins with low concentrations of nanocomposites could be used as possible materials for the prevention and treatment of denture stomatitis, due to their antibiofilm activities.

Do denture cleansers influence the surface roughness and adhesion and biofilm formation of Candida albicans on acrylic resin? Systematic review and meta-analysis.

To evaluate the influence of denture cleansers on the surface roughness, Candida albicans adhesion, and biofilm formation on denture base acrylic resins. Electronic databases and gray literature were searched using an individual search strategy. In vitro studies that evaluated the effects of immersion in denture cleansers on the surface roughness (µm) and antimicrobial activity (CFU/mL) on samples of heat-polymerized denture base acrylic resins were included. After screening, 17 studies were included, and a qualitative synthesis was performed. After assessing the risk of bias, only nine studies were included in the meta-analysis. The meta-analysis results showed that the evaluated solutions (0.5% sodium hypochlorite, 1% sodium hypochlorite, alkaline peroxide, and natural substances) did not influence the roughness of the acrylic resin. However, in the qualitative analysis, it was not possible to confirm an association between roughness and C. albicans adhesion and biofilm formation on the acrylic resin samples. Denture cleansers did not affect the surface roughness of denture base acrylic resins.

Effects of layer thickness and build angle on the microbial adhesion of denture base polymers manufactured by digital light processing.

To investigate the effects of printing-layer thickness and build angle on the surface characteristics and microbial adhesion of denture base polymers manufactured by digital light processing (DLP). Specimens were additively manufactured using DLP. The specimens were printed with different printing-layer thicknesses (25, 50, and 100 μm) and build angles (0°, 45°, and 90°). Scanning electron microscopy was used to observe the surface topography, and the arithmetical mean heights (Sa) were measured. Moreover, the initial Candida albicans (C. albicans) adhesion to the specimens was evaluated using an adhesion test. Finally, two-way ANOVA and Tukey's multiple comparison tests were conducted. The results regarding the Sa values exhibited a statistically significant interaction (F (4, 45) = 90.77, P < 0.0001). The build angle has a significant impact on the surface topography. Furthermore, quantitative results revealed that the printing-layer thickness significantly affected C. albicans adhesion (F (2, 99) = 6.96, P = 0.0015). The surface roughness was significantly affected by the printing-layer thickness and the build angle. Additionally, the surface topography was mainly determined by the build angle. Furthermore, the adhesion of C. albicans to the DLP-printed denture surfaces was significantly affected by the printing-layer thickness but not by the build angle. Consequently, it is critical to decrease the thickness of the printing layer to produce digital dentures with optimal material properties.

Функциональный потенциал колонизационной защиты буккальных эпителиоцитов как индикатор клинического течения заболеваний респираторного тракта

In the structure of children’s morbidity, one of the leading places is occupied by a class of respiratory diseases, which in quantitative terms is formed mainly by acute respiratory infections. The purpose — to investigate and evaluate the indicator significance of the functional potential of colonization defense in respiratory tract diseases.The paper presents the results of a study of colonization resistance indicators using modern research methods (colonization index, artificial colonization of the buccal epithelium and antiadhesive activity of saliva) in 184 patients aged 5 to 18 years with acute bronchitis, recurrent bronchitis and community-acquired pneumonia.Results. In a comparative aspect, the heterogeneity of the colonization level on buccal epitheliocytes of indigenous microflora (oral streptococci) was clearly traced, depending on the topic of the respiratory tract inflammatory lesion. Colonization resistance suffered the most in patients with community-acquired pneumonia. In patients of this group, the colonization index was within 0.89 (0.07) standard units (p &lt; 0.01), which was combined with a pronounced adhesion of Candida albicans on buccal epitheliocytes (r = -0.72). In patients with acute bronchitis, the colonization index was 1.86 (0.21) standard units; with recurrent course of bronchitis – 1.27 (0.19) units (p &lt; 0.01), while the indicators of the control group were 2.03 (0,18). The presence of less typical microorganisms in the oropharynx reflects the weakening of colonization resistance, signaling destabilization processes focused on the mucous membranes level.Conclusion. The deficiency of the mucosal protection functional reserve should be regarded as an unfavorable diagnostic marker of the course of a respiratory infection and the initiation of a bacterial inflammatory process in the respiratory system.

Microbial adhesion and viability on novel CAD/CAM framework materials for implant-supported hybrid prostheses.

The aim of the study was to investigate the adhesion and viability of Streptococcus oralis and Candida albicans under in vitro conditions on CAD/CAM framework materials for implant-supported hybrid prostheses. Twenty-nine specimens were prepared from each of three different materials: ZR (zirconia), PEEK (polyether ether ketone) and CoCr4 (CoCr4 alloy). The experimental part included surface roughness (SR) and contact angle of water (CAW) measurements, followed by colony forming unit (CFU), cell viability assay and scanning electron microscopy (SEM) analyses of Strep. oralis and C. albicans biofilms on the materials' surfaces. Kruskal-Wallis and one-way analysis of variance (ANOVA) tests were used for differences between materials, and the correlation between measurements was estimated using Spearman's correlation coefficient. PEEK specimens revealed higher SR, CAW and CFU mean values, than ZR and CoCr4 specimens. Strong positive correlation was found between SR and CFU and between CAW and CFU for both microbial species. Cell viability assay revealed similar values for both species across materials. Higher numbers of Strep. oralis and C. albicans on PEEK specimens confirm the impact of the higher surface roughness and contact angle values on the microbial adhesion and describes PEEK as less desirable than ZR and CoCr4 from microbiological aspect.

Highlights on Drug and Ion Release and Recharge Capacity of Antimicrobial Removable Prostheses.

This article aimed to review the ion and drug release, recharge abilities, and antimicrobial properties of drug/ion-releasing removable prostheses, and to assess their capability in preventing and inhibiting denture stomatitis as well preventing caries and reversing carious lesions. Data was collected from published scientific papers listed in PubMed database from January 1975 to December 2021. English full-text articles, involving clinical or in vitro studies, focusing on removable prostheses and are concerned with drug/ion release and rechargeability as a way to prevent or inhibit denture stomatitis or dental caries were included. The relevant articles reported that ion- or drug-modified polymethylmethacrylate acts as a reservoir for these ions and drugs and is capable of releasing significant amounts with sustained release effect. Recharging of modified resin resulted in greater sustainability of ion and drug release, thus improving the long-term effects of protection against demineralization and reducing the adhesion of Streptococcus mutans and Candida albicans. Modifications of removable prostheses with rechargeable ions and drugs enhance remineralization, hinder demineralization, and reduce microbial adhesion in difficult-to-access areas. Selection of denture base for clinical use will consider its ability to act as an ion/drug reservoir that is capable of release and recharge.