Candida-associated Denture Stomatitis Research Articles

Evaluating the antifungal effectiveness, leaching characteristics, flexural strength, and impact strength of polymethyl methacrylate added with small-scale silver nanoparticles - An in vitro study.

(1) To assess the release of stable silver nanoparticles (AgNPs) of small scale dimension added to heat polymerized polymethyl methacrylate (PMMA) in 6 months. (2) Assessing the influence of incorporating minimal concentrations of stable AgNPs with nanoscale dimensions into heat polymerized PMMA over a 6 month period on its antifungal efficacy (AF), flexural strength (FS), and impact strength (IS). Incorporating nanoparticles with a very small scale may have minimal impact on mechanical properties due to their diminutive size. However, the influence of these small scaled nanoparticles on antimicrobial efficacy and potential escalation in toxicity to host cells through leaching remains unexplored. AgNPs were prepared using an Ultrasonic Probe sonicator and the addition of ammonia to obtain stabilized AgNPs (< 0.01 nm) of small scale dimension. The characterization of these AgNPs involved ultraviolet visible spectroscopy, X ray diffraction, Zetasizer, and transmission electron microscopy with energy dispersive spectroscopy (TEM). The prepared AgNPs were then added in various percentages by weight (0%-0.5%) to fabricate 252 modified PMMA samples of sizes 10 mm × 3 mm (AF, n = 108), 65 mm × 10 mm × 3 mm (FS, n = 72), and 65 mm × 10 mm × 2.5 mm (IS, n = 72) as per ADA specification no. 12. These samples underwent testing for leaching out of AgNPs and efficacy against Candida albicans for 6 months. The effect on FS and IS was evaluated using the three point bending test and Charpy's Impact Tester, respectively. Intergroup comparison of CFU between various concentrations of AgNP was done using the Kruskal-Wallis ANOVA test succeeded by Mann-Whitney test for pair wise comparisons. Difference in CFU of various concentrations over 6 months was seen using one way ANOVA test. Intergroup comparison of FS and IS was performed using a one way ANOVA test, followed by a post hoc Tukey's test for pair wise comparisons. Repeated tests showed no leaching out of AgNPs from the denture base resin into the storage medium. All concentrations of AgNPs incorporated in resin showed inhibition of Candida growth. Intergroup comparison of FS and IS revealed highly statistically significant differences (F = 15.076, P < 0.01 and F = 28.266, P < 0.01) between the groups showing a reduction in strength. The AgNPs of small scale dimension incorporated into the denture base resin imparted a strong antifungal effectiveness against C. albicans, which did not decline during the study period and did not cause any release of nanoparticles. 0.5% showed the best antifungal efficacy. This may prove to be a viable and highly effective treatment for the prevention of Candida associated denture stomatitis. However, the inclusion of these particles resulted in a decrease in both FS and IS, and this reduction was directly proportional to the percentage of added AgNPs, with 0.5% demonstrating the least IS and FS.

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.

Candida-associated denture stomatitis: clinical, epidemiological, and microbiological features.

The identification of Candida spp. in denture stomatitis, the clinical manifestations, and the antifungal susceptibility profile lead to a correct and individualized therapeutic management of the patients. This study is aimed at investigating the clinical manifestations and epidemiological and microbiological characteristics of Candida-associated denture stomatitis. The samples were obtained by swabbing the oral mucosa of the subjects and then seeded onto Sabouraud Dextrose Agar and onto CHROMagar® Candida plates. The identification at the species level was confirmed byMatrix Assisted Laser Desorption Time of Flight Mass Spectrometry. Clinical classification was performed according to the criteria proposed by Newton (1962): (i) pinpoint hyperemia, (ii) diffuse hyperemia, and (iii) granular hyperemia. For carrying out the antifungal susceptibility testing, we adopted the CLSI M27-S4 protocol. C. albicans was the most prevalent species in our study. Regarding non-albicans Candida species, C. glabrata was the most common species isolated from the oral mucosa (n = 4, 14.8%), while in the prosthesis, it was C. tropicalis (n = 4, 14.8%). The most prevalent clinical manifestation was pinpoint hyperemia and diffuse hyperemia. Candida albicans, C. glabrata, and C. parapsilosis were susceptible to all the tested antifungals. Concerning fluconazole and micafungin, only two strains showed dose-dependent sensitivity (minimum inhibitory concentration (MIC), 1μg/mL) and intermediate sensitivity (MIC, 0.25μg/mL). One C. tropicalis strain was resistant to voriconazole (MIC, 8μg/mL). C. albicans was the most common species found in oral mucosa and prosthesis. The tested antifungal drugs showed great activity against most isolates. The most prevalent clinical manifestations were Newton's type I and type II.

In Vitro Antifungal Susceptibility of Candida Albicans Isolated from Yemeni Patients with Denture Stomatitis

Background and aims: Candida-associated denture stomatitis (CADS) is a common fungal infection in people who wear dentures. The main objectives of this study were to identify the causative agents of CADS and in vitro antifungal susceptibility testing (AFST) for Candida albicans in Yemeni patients with denture stomatitis. Methods: A total of 88 Candida spp. obtained from patients with denture stomatitis. Candida spp were identified using standard microbiological methods. The in-vitro antifungal susceptibility of Candida albicans. to fluconazole (FCZ), itraconazole (ICZ), voriconazole (VCZ), and amphotericin B (AMB) was evaluated using the E test strips. Interpretive sensitivity criteria for antifungal breakpoints were adapted from the Clinical and Laboratory Standards Institute (CLSI). Results: Overall, C. albicans was the most commonly isolated species (𝑛 = 60; 68.2%), followed by C. glabrata (𝑛 = 9; 10.2%), C. tropicalis (𝑛 = 7; 8%), and C. parapsilosis (𝑛 = 3; 3.4%). Voriconazole had the lowest geometric mean minimum inhibitory concentration which was 0.0418 𝜇g/ml for MIC50, and 0.957 𝜇g/ml for MIC90; followed by amphotericin B (AMB) in which MIC50 was 0.518 𝜇g/ml and for MIC90 was 1.06 𝜇g/ml. Conclusion: Our study showed that Candida albicans was the most prevalent Candida species in Yemeni patients with CADS and was susceptible to both azoles and amphotericin B. In addition, voriconazole could be a suitable alternative to antifungal agents currently used in the treatment of CADS, as well as in the treatment of recurrent Candidasis.

Evaluation of Candida albicans biofilm formation on conventional and computer-aided-design/computer-aided manufacturing (CAD/CAM) denture base materials.

The human mouth mucosal surface is colonized by indigenous microflora, which normally maintains an ecological balance among different species. However, certain environmental or biological factors may disrupt this balance, leading to microbial diseases. Candida albicans biofilms are formed on indwelling medical devices and have an association with both oral and invasive candidiasis. This study aimed to compare the amount of adherent C. albicans and the biofilm formed on different denture base materials. The adhesion of C. albicans to denture base materials is widely recognized as the main reason for the development of denture stomatitis. In total, 56 polymethyl methacrylate (PMMA) acrylic resin disc-shaped samples were divided into four groups as follows: 1) chemically polymerized PMMA, 2) heat-polymerized PMMA, 3) computer-aided design and computer-aided manufacturing (CAD/CAM) PMMA in high polish, and 4) CAD/CAM resins in glazed form. The adherent cells and formation of C. albicans strains (562, 1905, 1912, and 1949) biofilm were measured by the 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT) method and use of a microplate reader. Moreover, morphological alterations of C. albicans cells were investigated using scanning electron microscopy (SEM). The biofilm formation was significantly lower on CAD/CAM acrylic resins, compared to conventional denture base materials. The obtained results were confirmed by the SEM images of C. albicans biofilms. CAD/CAM PMMA-based polymers may be preferable to inhibit C. albicans biofilm formation and reduce Candida-associated denture stomatitis in long-term use. Based on the findings, the CAD/CAM technique can be used as an efficient technique for denture fabrication as it inhibits microbial accumulation, and consequently, microbial biofilm.

Evaluation the efficiency of purified prodigiosin pigment from Serratia marcescens as antibiofilm formation agent against Candida spp. causing of denture stomatitis

An infection of the human oral cavity that is primarily fungal is called Candida-associated denture stomatitis. Erythema of the palate and alveolar ridges are symptoms of denture stomatitis, which is a persistent inflammatory condition of the mucosa supporting dentures. So that a red pigment made by Serratia marcescens and designated as prodigiosin was purified by silica gel column chromatography with a yield of 3.7 g/l after being extracted at higher concentrations using methanol with a yield of 3.3 g/l. Additionally, a UV scan of the pigment revealed that its highest absorbance occurred at 535 nm, and thin layer chromatography revealed that it had an Rf value of 0.86 when compared to standard. In cases of oral or denture stomatitis, Candida albicans was the dominating species followed by C. tropicalis, C. parapsilosis and C. dubliniensis, respectively. Checking for the development of biofilms by Candida spp. revealed that C. albicans and C. tropicalis produced biofilm but in different levels. The most effective source of biofilm production was C. albicans isolates. Candida species were prevented from forming biofilms by the purified prodigiosin. Candida albicans isolates had a greater proportion of biofilm inhibition, ranging from 63 to 82%. In contrast, the percentage of inhibition for isolates of C. tropicalis varied between 57 and 61%. Prodigiosin has a favorable advantage for potential usage in the dental sector since it stops and prevents the growth of biofilm.

In vitro antimicrobial effects of chitosan on microcosm biofilms of oral candidiasis

ObjectiveThis study assessed the effects of chitosan (CS) on microcosm biofilms derived from saliva of patients with Candida-associated denture stomatitis. MethodsFive removable denture wearers with denture stomatitis were included in the study. The minimum inhibitory concentration (MIC) of CS against clinical isolates of Candida albicans was determined according to the broth microdilution method. Pooled saliva from the donors was used as an inoculum for the formation of biofilms, which were developed during 72 h on acrylic surfaces in the Amsterdam Active Attachment model. The biofilms were then treated with different concentrations of CS, and the antibiofilm effects were evaluated through the quantification of colony-forming units (CFUs), total biomass (TB), metabolic activity (MA), lactic acid production (LAP), and cell viability (by confocal laser scanning microscopy). Chlorhexidine, miconazole, and nystatin were tested as positive controls, while the negative control (NC) was the untreated biofilm. Data were analyzed by 1-way ANOVA and Fischer LSD's post hoc test (α=0.05). ResultsMIC values of CS ranged from 500 to 800 µg/mL. For CFUs, 2500 µg/mL CS was the most effective treatment in reducing total anaerobes, mutans streptococci, and Lactobacillus spp., significantly differing from the controls. For C. albicans CFUs, CS and positive controls did not differ from each other but led to significant reductions compared to NC. Regarding TB, MA, LAP, and cell viability, 2500 µg/mL CS promoted the greatest reductions compared to NC. ConclusionCS has similar or superior effects to conventional active principles on important parameters of oral candidiasis microcosm biofilms. Clinical RelevanceThe antibiofilm effects of CS show that this compound has great potential to improve the clinical condition of denture stomatitis patients, and formulations containing this natural polymer could be useful for controlling oral candidiasis.

Effect of denture liners surface modification with Equisetum giganteum and Punica granatum on Candida albicans biofilm inhibition.

Aim: This study investigated the effect of denture liners surface modification with Equisetum giganteum (EG) and Punica granatum (PG) on Candida albicans biofilm inhibition supposing its usage as a sustained-release therapeutical delivery system for Candida-associated denture stomatitis. Materials & methods:C. albicans biofilm (SC5314 or ATCC 90028) was formed on soft liners superficially modified by a primer mixed to drugs at minimum inhibitory concentrations (0.100g for EG and PGor 0.016g for nystatin per mlof primer). After 24h, 7 or 14days, antibiofilm activity was evaluated by colony-forming unit counts. Results: Not all groups were equi-efficient to nystatin after 24h and 7days. After 14days, EG and PG efficacies were not different from nystatin (almost 100% inhibition). Conclusion: The proposed protocol presents a promising option to allopathic drugs for Candida-associated denture stomatitis treatment.

Prevalence of Candida among Denture Wearers and Nondenture Wearers.

Introduction:A denture wearer is highly prone to develop Candida-associated denture stomatitis (CADS) due to the conversion of the normal oral commensal Candida spp. into a pathogen under favorable conditions. Immuno-compromised status, trauma from the prosthesis, other systemic conditions, and improper maintenance of the dentures by the patient are few of the causative agents which turn the oral balance into an unhealthy and unsuitable foundation for the wearing of the prosthesis.Objective:The objective of this study was to compare subjects wearing complete dentures and nondenture wearers regarding Candida isolates associated with disease and colonization among the different age groups.Methodology:A cross-sectional study was conducted among 60 subjects, 30 wearing complete dentures (Group-A) and 30 nondentures wearers (Group-B), were matched for gender, race, and age. The unstimulated saliva sample was collected and cultured in CHROMagar using standard protocols.Results:The mean value of the candidal colony-forming units with respect to Group A is Candida Albicans 0.36 ± 2.008, Candida krusei 0.27 ± 1.061, P value Group B: C. albicans 0.73 ± 2.196, C. krusei 0.36 ± 1.084. There was a significant relation between denture wearers and heavy growth of C. albicans and C. krusei in saliva culture with a P value of P-0.054 and P-0.036, respectively.Conclusions:These results indicate that denture wearers with oral Candida had a higher prevalence of CADS. Patients with removable prostheses should be informed about the importance of proper prosthesis and personal hygiene since dentures and age-related immunosuppression are both well-known risk factors associated with candidiasis development, the presence of yeast, even in healthy denture wearers, should be considered a risk factor for denture stomatitis that increases with the duration of denture use.

Efficacy of antimicrobial photodynamic therapy compared to nystatin therapy in reducing Candida colony count in patients with Candida-associated denture stomatitis: a systematic review and meta-analysis.

Purpose This meta-analysis assessed the efficacy of antimicrobial photodynamic therapy (aPDT) compared to conventional nystatin therapy (NYT) in reducing Candida colony count in patients with Candida-associated denture stomatitis (CADS) and critically appraised the available literature.Methods This meta-analysis was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) updated guidelines. A literature search was performed in four electronic databases to identify relevant articles up to 15 August 2021. Randomised controlled trials (RCTs) that assessed the efficacy of aPDT compared to NYT in reducing Candida colony count in patients with CADS were investigated. The weighted mean difference (MD) and 95% confidence interval were calculated. The I2 statistic was used to determine heterogeneity at the level of α = 0.10. The Cochrane risk of bias (RoB 2) tool was used to assess the risk of bias. Certainty of the evidence was determined using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) ranking system.Results Only three eligible RCTs with 141 participants were included in this systematic review and meta-analysis. Based on the pooled results, NYT compared to aPDT generally performed better in reducing Candida colony count (Log10 CFU/mL) in patients' palate and patients' denture. The included studies had a moderate risk of bias and the certainty of the evidence was low.Conclusion Although still inconclusive, based on the current evidence, aPDT may be effective in reducing Candida colony count and treating CADS. Nonetheless, it does not appear to be more effective than conventional NYT in this regard. According to the limited number of included studies, more well-designed RCTs with larger sample sizes and standardised methodology should be conducted to validate this conclusion.

Antifungal Effect of Piezoelectric Charges on PMMA Dentures.

Candida-associated denture stomatitis is a recurring disease affecting up to 67% of denture wearers. Poly(methyl methacrylate) (PMMA) remains the main material employed in the fabrication of dentures due to its desirable physical, mechanical, and aesthetic properties. However, the improvement of its antimicrobial properties remains a challenge. To address this need, we developed PMMA composite filled with piezoelectric nanoparticles of barium titanate (BaTiO3) for therapeutic effects. Candida albicans biofilms were cultivated on the surface of the composites under continuous cyclic mechanical loading to activate the piezoelectric charges and to resemble mastication patterns. The interactions between biofilms and biomaterials were evaluated by measuring the biofilm biomass, metabolic activity, and the number of viable cells. To explore the antifungal mechanisms, changes in the expression of genes encoding adhesins and superoxide dismutase were assessed using reverse transcription-polymerase chain reaction. With the addition of piezoelectric nanoparticles, we observed a significant reduction in the biofilm formation and interference in the yeast-to-hyphae transition compared to the standard PMMA. Moreover, we observed that the cyclic deformation of biomaterial surfaces without antifungal agents produced increased biomass, metabolic activity, and a number of viable cells compared to the static/no-deformed surfaces. Cyclic deformation appears to be a novel mechanobiological signal that enables pathogenicity and virulence of C. albicans cells with increased expression of the yeast-to-hyphae transition genes. The outcome of this study opens new opportunities for the design of antifungal dentures for improved clinical service and reduced need for cleaning methods.

Secretory immune status of oral cavity in the patients with &lt;i&gt;Сandida&lt;/i&gt;-associated denture stomatitis

Age-related changes in the oral mucosa immunity, including decreased contents of secretory immunoglobulins and antimicrobial peptides in saliva, along with changed balance of pro- and antiinflammatory cytokines, care risks for development of purulent-inflammatory or allergic diseases of the oral cavity. For example, denture stomatitis (DS) caused by Candida albicans occurs in about 30—70% of denture users. The purpose of this study was to assess the secretory immune state of oral mucous membranes in the patients with Candida-associated denture stomatitis. We examined 42 elderly patients (61-72 years old) with one-piece acrylic dentures for at least, 6 months (15 men and 27 women). Based on clinical and microbiological studies, the patients were divided into a group with DS (n = 24) and a group without DS (n = 18). The contents of secretory immunoglobulin A (sIgA) and proinflammatory cytokines was determined, i.e., interleukin-1β (IL-1β), interleukin-6 (IL-6), interleukin-8 (IL-8), tumor necrosis factor-α (TNFα), and anti-inflammatory cytokines, e.g., receptor antagonist of interleukin-1 (RAIL), interleukin-4 (IL-4), interleukin-10 (IL-10), as well as antimicrobial peptides (cathelicidin LL-37, lactoferrin and alphadefensins 1-3 (HNP1-3). The sIgA levels in the salivary fluid of patients with DS (0.92 (0.80-1.26) g/l) were significantly lower (p &lt; 0.05) than in patients without stomatitis (1.71 (1.23-2,13) g/l). In the group with advanced DS, a significant increase of IL-1β levels in saliva was observed, along with simultaneous decrease of IL-8 concentrations, compared to the other group, without differences in TNFα and IL-6 concentrations. Increased contents of IL-10 in saliva was also noted. It was shown that the concentrations of cathelicidin LL-37 in saliva of the DS patients was increased two-fold, whereas the contents of neutrophil-derived alpha-defensins (HNP 1-3) was decreased. Conclusions: The development of inflammation in denture stomatitis caused by usage of removable acrylic dentures associated with Candida albicans infection is characterized by functional insufficiency of the secretory immunity of the oral mucosa associated with decreased amounts of secretory immunoglobulin A and antimicrobial peptides of neutrophilic origin. Low levels of alpha-defensins may suggest a decrease in the functional activity of neutrophils in the elderly, thus leading to higher susceptibility to fungal infection of oral cavity.

Inhibition of Candida albicans and Mixed Salivary Bacterial Biofilms on Antimicrobial Loaded Phosphated Poly(methyl methacrylate).

Biofilms play a crucial role in the development of Candida-associated denture stomatitis. Inhibition of microbial adhesion to poly(methyl methacrylate) (PMMA) and phosphate containing PMMA has been examined in this work. C. albicans and mixed salivary microbial biofilms were compared on naked and salivary pre-conditioned PMMA surfaces in the presence or absence of antimicrobials (Cetylpyridinium chloride [CPC], KSL-W, Histatin 5 [His 5]). Polymers with varying amounts of phosphate (0–25%) were tested using four C. albicans oral isolates as well as mixed salivary bacteria and 24 h biofilms were assessed for metabolic activity and confirmed using Live/Dead staining and confocal microscopy. Biofilm metabolism was reduced as phosphate density increased (15%: p = 0.004; 25%: p = 0.001). Loading of CPC on 15% phosphated disks showed a substantial decrease (p = 0.001) in biofilm metabolism in the presence or absence of a salivary pellicle. Salivary pellicle on uncharged PMMA enhanced the antimicrobial activity of CPC only. CPC also demonstrated remarkable antimicrobial activity on mixed salivary bacterial biofilms under different conditions displaying the potent efficacy of CPC (350 µg/mL) when combined with an artificial protein pellicle (Biotene half strength).

DENTURE BIOFILM AND DENTUREASSOCIATED STOMATITIS, A LITERATURE REVIEW

Denture stomatitis is increased dramatically in the recent years, particularly in denture wearers. It is a common inflammatory reaction with multifactorial etiology that usually appears in the oral cavity as an erythematous reaction on the oral mucosa extends to the limits of the maxillary denture-bearing area. Candida albicans is regarded as the primary cause of denture-associated stomatitis owing to its high capability to adhere to oral tissues and denture surfaces in addition to biofilms formation. Candida species can interact with different microorganisms within the mouth resulting in a complex and mixed biofilm formation with an organized structure which is difficult to remove. The presence of bacteria in the acrylic biofilms resulted in increased pathogenicity and virulence of Candida biofilms making them more resistance to antifungal drugs. This article was introduced to highlight on the denture biofilm microbiota and its role in Candida albicans pathogenicity in addition to exploring the clinical manifestation, multifactorial etiology and management policies of Candida-associated denture stomatitis frequently faced in dental clinic.An online search of PubMed, Scopus, Science Direct, and Google Scholar was conducted using key words (Microbiota, Candida albicans, Denture stomatitis, Biofilm) from 1978 up to 2021. The management of denture stomatitis mainly depends on enhancement of oral hygiene processes, description of antifungal agents either topical or systemic, as well as disinfectants description. Recently, medical extracts that possess antimicrobial activity against oral pathogens was introduced as a safe and less side effects protocol for management of denture stomatitis.

Microflora in denture stomatitis - A review

Denture stomatitis is an inflammation that typically occurs in individuals that have a complete or partial denture. Denture stomatitis is commonly defined as persistent inflammatory changes in the mucosa-bearing denture surface, often characterized by palatal erythema and alveolar ridges on which the denture is mounted. All relevant search engines were searched for the literature pertaining to denture stomatitis, various microflora associated, prevention and treatment were searched. The required data was collected and quality analysis of the thus collected data was done. The knowledge in the current point of time-analyzed and thus the consensus was established. Denture stomatitis is induced by a variety of internal and external causes. The most pervasive causative factor for denture stomatitis is the concentration of microbial plaque on palate-covered removable dentures that cause denture stomatitis in close to 69% of denture wearers. The various microflora includes Candida, Streptococci, Staphylococci, Lactobacillus, Actinomyces, etc. Denture stomatitis has been shown to be a major oral disease seen on the denture wearers and is still prevalent in the majority of cases. Candida-associated denture stomatitis must be treated as it may serve as a repository for other infections and facilitate atrophy of the alveolar bone resulting in serious infections.

Association between Vitamin D and Candida-Associated Denture Stomatitis.

Candida-associated denture stomatitis (CADS) is a fungal infection affecting 60–65% of denture wearers. Its etiology is complex and multifactorial and often associated with host immunodeficiency. Evidence exists that vitamin D has potential immunomodulatory and anti-inflammatory effects. The aim of this case–control study was to assess the association between vitamin D levels and CADS. The study included 32 complete denture wearers with CADS and 32 sex- and age-matched complete denture wearers without CADS. The patients were clinically examined, and the severity of denture stomatitis was assessed according to Newton’s classification scale. The serum vitamin D level was determined via the use of an electrochemiluminescence assay. The vitamin D level in the CADS group and control group was 54.68 ± 17.07 and 56.82 ± 17.75 nmol/L, respectively. There was no significant difference between the groups (p = 0.622). Univariate logistic regression analysis showed that the presence of CADS was not associated with hypovitaminosis D (odds ratio (OR) = 1.44; 95% confidence interval (CI) = 0.37–5.54). It can be concluded that vitamin D is not associated with CADS and does not play a significant role in host susceptibility to CADS. This finding suggests that vitamin D screening is not indicated routinely in patients with Candida-associated denture stomatitis.

The effectiveness of microwave disinfection in treating Candida-associated denture stomatitis: a systematic review and metaanalysis.

To evaluate the effectiveness of microwave disinfection in treating Candida-associated denture stomatitis (CADS). The PubMed/MEDLINE, Embase, and Scopus databases were searched for reports on randomized clinical trials (RCTs) published in English until May 2020 (PROSPERO CRD42020192062) that evaluated the treatment of CADS by using microwave disinfection. The main outcomes were the improvement of clinical signs and/or the decrease in the residual yeast present on the dentures and palatal mucosa. The mean differences, standard deviations, risk ratio, and 95% confidence interval were calculated by using the random-effects model. Heterogeneity was assessed by using Cochran's Q test and I2 values. The level of significance was set at α = 0.05. Five RCTs with 245 participants were included. The descriptive investigations demonstrated that microwave disinfection was as effective (p > 0.05) as 0.2% chlorhexidine, 0.02% sodium hypochlorite, and topical nystatin (100.000 IU/mL), and was superior to topical miconazole in treating CADS. The metaanalysis did not show a statistical difference between microwave disinfection and nystatin (100.000 IU/mL) treatment in terms of mycological counts, cure, and recurrence rates (p > 0.05). Microwave disinfection showed comparable results with those of conventional therapies for treating CADS. In addition, treatment with 650 W for 3 min once a week for 14 days had better cost-effect results, indicating both the prevention and treatment of CADS. Our findings provide evidence regarding the treatment of CADS using microwave disinfection, and also indicating the best cost-effective option for this treatment modality.

Biocompatible silver nanoparticles incorporated in acrylic resin for dental application inhibit Candida albicans biofilm.

Although silver nanoparticles (SNP) have proven antimicrobial activity against different types of microorganisms, the effect of SNP incorporation into acrylic resin to control Candida albicans biofilm formation aiming at the prevention of Candida-associated denture stomatitis has not yet been fully elucidated. This study aimed to evaluate the antimicrobial effect of an acrylic resin containing SNP on C. albicans biofilm growth, the flexural strength of this material and tissue reaction in the subcutaneous connective tissue of rats to SNP. SNP were synthesized through silver nitrate reduction by sodium citrate. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) were used to verify the size and colloidal stability. SNP were added to acrylic resin monomer (Lucitone 550) at 0.05, 0.5 and 5vol%. The antimicrobial effect against C. albicans (ATCC 10231) was investigated by the enumeration of colony-forming units (CFUs) and SEM. The three-point bending test was performed to analyze the flexural strength. Tissue reaction was evaluated after 7 and 60days of implantation in the connective tissue of Wistar rats. Spherical particles of 5 and 10nm were obtained. SNP at 0.05 and 0.5% incorporated into acrylic resin was effective in reducing C. albicans biofilm growth (p<.001). SEM revealed that the material was able to disrupt C. albicans biofilm formation and did not reduce the flexural strength compared to control (p>.05). The inflammatory response observed 60days after implantation SNP in the subcutaneous tissue was similar to control. It was concluded that SNP addition at 0.05 and 0.5% into acrylic resin exhibited antimicrobial effects against C. albicans biofilm, did not interfere in the flexural strength and may be considered biocompatible.

Biocompatibility and Antimicrobial Activity of Reynoutria elliptica Extract for Dental Application.

This study was conducted to determine whether nature-derived Reynoutria elliptica extracts exhibit biocompatibility and antimicrobial effects against oral pathogens such as Streptococcus mutans and Candida albicans. Fine particles of Reynoutria elliptica extract were used to probe for biocompatibility and antimicrobial activity toward these pathogens, and results were evaluated with an MTT (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) assay, spectrophotometric growth inhibitory assay, the total number of colony-forming units (CFU), an agar disk diffusion test, and scanning electron microscopy (SEM). In addition, UV/VIS spectroscopy was used to determine the levels of flavonoid and polyphenol in experimental solutions. Several experimental groups showed cell viability higher than 70%, and the antimicrobial activity toward both S. mutans and C. albicans was significantly higher than was that seen for the control group. In CFU and agar disk diffusion tests with C. albicans, increases in the concentration of Reynoutria elliptica extract led to significantly increased antimicrobial effects. Additionally, SEM results showed that Reynoutria elliptica extract changed the morphology and density of S. mutans and C. albicans. The results of this research can be applied to the use of Reynoutria elliptica extracts for the development of oral products that are biologically friendly and can control oral diseases such as dental caries and candida-associated denture stomatitis.

Candida-Associated Denture Stomatitis and Murine Models: What Is the Importance and Scientific Evidence?

Considering the high prevalence and recurrence of Candida-associated denture stomatitis (CADS), in vivo studies in animal models are necessary before those in humans to evaluate new therapeutic strategies. This study aimed to review the literature on murine models of CADS induction using acrylic intraoral devices simulating dentures. Rats are recommended as experimental animals in these models as well as the adoption of a pasty diet. For maintenance in the proper position during the experiments, intraoral appliances must be obtained by individual impressions, using and retained exclusively by cementation on the molars. The region of interest for histopathological analysis was standardized as that corresponding to the area between the first molars. However, there is no consensus among the studies on the CADS induction rat models in relation to the Candida albicans inoculation and need for immunosuppression and/or administration of antibacterial drugs of animals. The greatest difficulty of the available models refers to maintaining the course of the lesion for a sufficient period to evaluate the effectiveness of the proposed treatment, considering the rapid and efficient murine immune response to candidal colonization. Therefore, future studies are necessary for the development of a robust and reproducible CADS model.