Predisposing conditions forCandidaspp. carriage in the oral cavity of denture wearers and individuals with natural teeth

Efficacy of chemical and Photoactivated disinfectants against Candida Albicans and assessment of hardness, roughness, and mass loss of acrylic denture base resin

AIM

The present study aimed to assess the antimicrobial efficacy of hematoporphyrin derivative, sodium hypochlorite (NaOCl), glutaraldehyde (GaH), and a chlorhexidine (CHX) on mass loss (ML), microhardness, and surface roughness (Ra) of acrylic denture base colonized with C. Albicans.

MATERIAL AND METHODS

A total of 40 heat cure acrylic resin dentures were fabricated and inoculated by the American Type Culture Collection (ATCC) of C. Albicans in an in-vitro situation. Specimens were divided into four groups (n=10) based on the method of disinfection. Hematoporphyrin derivatives, 1% NaOCl, 2% GaH, and 4% CHX.The pre and post candida (CFU/ml) counts were recorded before and after immersion. ML, microhardness, and Ra of acrylic denture were also assessed. Statistical analysis was executed for CFU/mL (log10) for exposed C. Albicans by two-way ANOVA and Tukey's multiple tests (p>0.05). For normality of the data, Dunnet's Simultaneous test was performed.

RESULTS

In terms of candida strain analysis, pretreatment to posttreatment comparisons revealed a reduction in mean Candida count in all groups (p<0.05). The highest ML value after post candida disinfection of acrylic denture was observed in 2% GaH (1.587 ± 0.25) treated specimens. The least microhardness value was found in group 1 when treated with hematoporphyrin (0.97 ± 0.22 VHN) which was significantly different from other groups (p<0.05). Group 1 surface treated with hematoporphyrin derivate (1.84 ± 0.22 μm) showed the highest Ra values (p<0.05).

CONCLUSION

Acrylic denture base resin colonized with C. Albicans when treated with a chemical disinfectant of 4% chlorhexidine displayed the highest antimicrobial efficacy with reduced mass loss, less surface roughness, and maximum denture hardness.

Type 2 diabetes mellitus and oral Candida colonization: Analysis of risk factors in a Sri Lankan cohort

Aims: Oral candidiasis is a major oral manifestation of uncontrolled diabetes mellitus, and a number of cofactors are associated with the pathogenesis of this infection. Here, we describe the prevalence of oral Candida in a Sri Lankan cohort of type 2 diabetes mellitus and risk factors that predispose them to this common fungal infection. Methods: A case-control study was conducted in 250 diabetics with type 2 diabetes and 81 nondiabetic controls. Clinical and demographic data were collected using an interviewer administered questionnaire, and patient records. Oral rinse samples were collected to determine the candidal carriage, and the resultant yeast growth was quantified and speciated using multiplex-PCR and phenotypic analyses. Chi-square test (χ² test) and Fisher exact test were used for the determination of the significant relationships between risk factors and oral candidiasis. Results: The oral prevalence of Candida species among both groups was similar (81%) although a significantly higher proportion of diabetics (32.8%) yielded >2000 CFU/mL of yeasts compared with only 12.3% of the healthy controls (p < .05). Significant associations were noted between oral candidal carriage amongst diabetics, and (i) denture wearing, (ii) female gender and (iii) cigarette smoking (all, p < .05). Amongst both groups, C.albicans was the most common Candida species isolated followed by C. parapsilosis, C. tropicalis and C. glabrata. Conclusions: The oral infestation of Candida in our Sri Lankan cohort of diabetics is significantly higher than their healthy counterparts, and co-carriage of multiple yeast species is a common finding in the study population. As there are no previous such reports of the latter phenomenon particularly from the Asian region it is noteworthy, mainly in view of the recent data on the emergence of drug-resistant yeast species the world over.

Synergistic Effect of Quinic Acid Derived From Syzygium cumini and Undecanoic Acid Against Candida spp. Biofilm and Virulence

In recent decades, fungal infections have incredibly increased with Candida genus as the major cause of morbidity and mortality in hospitalized and immunocompromised patients. Most of the Candida species are proficient in biofilm formation on implanted medical devices as well as human tissues. Biofilm related Candida infections are very difficult to treat using common antifungal agents owing to their increased drug resistance. To address these issues, the present study investigated the antibiofilm and antivirulent properties of Syzygium cumini derived quinic acid in combination with known antifungal compound undecanoic acid. Initially, antibiofilm potential of S. cumini leaf extract was assessed and the active principles were identified through gas chromatography and mass spectrometry analysis. Among the compounds identified, quinic acid was one of the major compounds. The interaction between quinic acid and undecanoic acid was found to be synergistic in the Fractional inhibitory concentration index (≤0.5). Results of in vitro assays and gene expression analysis suggested that the synergistic combinations of quinic acid and undecanoic acid significantly inhibited virulence traits of Candida spp. such as the biofilm formation, yeast-to-hyphal transition, extracellular polymeric substances production, filamentation, secreted hydrolases production and ergosterol biosynthesis. In addition, result of in vivo studies using Caenorhabditis elegans demonstrated the non-toxic nature of QA-UDA combination and antivirulence effect against Candida spp. For the first time, synergistic antivirulence ability of quinic acid and undecanoic acid was explored against Candida spp. Thus, results obtained from the present study suggest that combination of phytochemicals might be used an alternate therapeutic strategy for the prevention and treatment of biofilm associated Candida infection.

Rapid Phenotypic and Genotypic Diversification After Exposure to the Oral Host Niche in Candida albicans

In vitro studies suggest that stress may generate random standing variation and that different cellular and ploidy states may evolve more rapidly under stress. Yet this idea has not been tested with pathogenic fungi growing within their host niche in vivo Here, we analyzed the generation of both genotypic and phenotypic diversity during exposure of Candida albicans to the mouse oral cavity. Ploidy, aneuploidy, loss of heterozygosity (LOH), and recombination were determined using flow cytometry and double digest restriction site-associated DNA sequencing. Colony phenotypic changes in size and filamentous growth were evident without selection and were enriched among colonies selected for LOH of the GAL1 marker. Aneuploidy and LOH occurred on all chromosomes (Chrs), with aneuploidy more frequent for smaller Chrs and whole Chr LOH more frequent for larger Chrs. Large genome shifts in ploidy to haploidy often maintained one or more heterozygous disomic Chrs, consistent with random Chr missegregation events. Most isolates displayed several different types of genomic changes, suggesting that the oral environment rapidly generates diversity de novo In sharp contrast, following in vitro propagation, isolates were not enriched for multiple LOH events, except in those that underwent haploidization and/or had high levels of Chr loss. The frequency of events was overall 100 times higher for C. albicans populations following in vivo passage compared with in vitro These hyper-diverse in vivo isolates likely provide C. albicans with the ability to adapt rapidly to the diversity of stress environments it encounters inside the host.

A quest to find good primers for gene expression analysis of Candida albicans from clinical samples

Biofilm production contributes to several human diseases, including oral candidiasis. Among the Candida species, Candida albicans is the most prevalent. The expression of virulence genes is implicated in the pathogenic potential of Candida biofilms. However, the evaluation of microbial gene expression from in vivo biofilm samples is not trivial, specifically, assessment via quantitative PCR (qPCR) can be a challenge because of several species present in clinical samples. Hence, the necessity of primers specificity. The aim of this study was to evaluate through in silico and in vitro analyses the specificity of published primers and newly designed primers for C. albicans virulence genes: ALS1, CAP1, CAT1, EFG1, HWP1, LIP3, PLB1, SAP1, SAP4, SOD1, SOD5 and ACT1 (normalizing gene). In silico analysis was performed through a PubMed search of articles with primer sequences that evaluated gene expression of C. albicans. Then, the sequence similarity of twenty-eight primers was checked through BLASTn and ClustalW2. The analysis of secondary structures was performed using mfold. When the primers did not present satisfactory characteristics (absence of secondary structures, not discrepant Tm of forward and reverse sequences and specificity) following in vitro analysis (i.e., end point PCR), new primers were designed using Beacon Designer™ and sequences obtained from the "Candida Genome Database". The selected primers were tested in vitro by end point PCR using a panel of genomic DNA from five different Candida species (C. albicans, Candida glabrata, Candida dubliniensis, Candida krusei, and Candida tropicalis). The resulting PCR products were visualized on agarose gel. qPCR reactions were performed to determine primers' optimal concentration and PCR efficiency. End point PCR demonstrated that published primers for the SAP1 and HWP1 were specific for C. albicans and the one for SOD1 reacted with C. albicans and C. dubliniensis. The sequence of primers designed for ACT1, ALS1 and HWP1 genes were specific for C. albicans, while the ones for CAP1, CAT1, EFG1, LIP3, and PLB1 were detected in C. albicans and C. dubliniensis. After optimization, all primers presented a single peak on melt curves, correlation coefficient of ≅1 and qPCR reaction efficiency of 90-110%, with slope of ≅-3.3. Therefore, these primers should be suitable for future gene expression analyses from clinical samples.

Approach to the most prevalent oral disorders among the elderly: an integrative review focusing on primary health care

Abstract Objective: an integrative review of the treatment of oral candidiasis, root caries and xerostomia among the elderly population, focusing on Primary Health Care, was carried out. Method: scientific articles were collected from the MEDLINE/PUBMED database using the keywords "Geriatric dentistry" and "Oral health", crossed with corresponding descriptors, together with specific terms for the pathologies studied, and with “the clinical trial” filter activated. The abstracts of the articles were read by three researchers. Result: oral candidiasis: six randomized clinical trials and one quasi-experimental design study, on the treatment of prosthetic stomatitis by medication and/or the disinfection of dentures by different techniques, were identified; root caries: three randomized clinical trials were included, which tested the use of mouthwash with chlorhexidine solution and oral hygiene instruction associated or otherwise with other drugs; and xerostomia: two articles were analyzed using various medications, and the functional massage of the salivary glands and associated muscles. Conclusion: The results demonstrate a variety of treatment options for the studied clinical situations, although these should be adapted to the characteristics of the services and the population, as standard treatment in Primary Health Care has not been established. Strategies based on soft technologies, such as health education, seem to provide good results. The present study provides additional knowledge for health professionals in search of more resolutive and qualified dental care for the elderly in primary health care.

Effect of Dentin Disinfection with 2% Chlorhexidine Gluconate and 0.3% Iodine on Dentin Bond Strength: An in vitro Study

Objective

Cavity preparation is a surgical procedure that attempts to remove all infected dentin.¹ Bacteria left beneath the filling material is greatest threat to the pulp. To reduce the potential for residual caries development and sensitivity, an antibacterial solution with the ability to disinfect the prepared tooth surface would be of help.² So this study was conducted to evaluate and compare the effect of dentin disinfection with 2% chlorhexidine gluconate (Consepsis) and 0.3% iodine (Ora5) on shear bond strength (SBS) of self-etch adhesives to dentin.

Materials and methods

Buccal surfaces of 36 caries-free permanent third molars were ground to expose dentin. All specimens were mounted on acrylic block, divided randomly into three groups, namely group I (control), group II (Con-sepsis), and group III (Ora5). After the application of cavity disinfectant and bonding procedures as per manufacturer’s instructions, composite cylinders were built. Then SBS was measured using universal testing machine.

Results

Statistical analysis of the measurements were made using one-way analysis of variance (ANOVA), which showed that when cavity disinfectants (Consepsis and Ora5) were used there was significant reduction in SBS of composite to dentin when compared with that of control group.

Interpretation and conclusion

The results indicate that the use of commercially available cavity disinfectants, Consepsis containing 2% chlorhexidine gluconate and Ora5 containing 0.3% iodine and 0.15% potassium iodide with self-etch adhesive (Adper Prompt), would significantly lower SBS of composite to dentin.

How to cite this article

Suma NK, Shashibhushan KK, Reddy VVS. Effect of Dentin Disinfection with 2% Chlorhexidine Gluconate and 0.3% Iodine on Dentin Bond Strength: An in vitro Study. Int J Clin Pediatr Dent 2017;10(3):223-228.

Correlation between age and gender in Candida species infections of complete denture wearers: a retrospective analysis

Aim

Denture-related stomatitis is a disorder that often affects denture wearers. The purpose of this study was to evaluate the intensity, genera, and frequency of yeasts in the oral cavity of complete denture wearers in terms of subject gender and age.

Materials and methods

Nine hundred twenty patients (307 males and 613 females) with complete upper dentures were selected for the study and divided into four age groups: ≤50 years, 51–60, 61–70, and >70 years. Yeast samples were taken as a smear from the palate. The data were collected from January 15, 2007 to January 15, 2012.

Results

The distribution of the number of yeast colonies by gender was statistically significant (P=0.02). Across all subjects, there was a statistically significant relationship between the intensity of yeast growth and the gender (P=0.01). In every age group, the number of infection-free individuals was greater among males than females. Intermediate, intense, and abundant growth of yeast occurred most frequently in the youngest group of females.

Conclusion

The genera of Candida species and the frequency of yeast infection in denture wearers appear to be influenced by both age and gender. The complete denture wearers ≤50 years of age appeared to have the greatest proclivity to oral Candida infections.

The effect of nanochitosans particles on Candida biofilm formation

Background and Purpose:

In people wearing dentures, the growth of various Candida species under the prosthesis leads to the formation of biofilm, which can play the role of a reservoir for Candida and other kinds of microbes. Since nano-chitosan particles can cause lasting antimicrobial activity, a more recent approach that utilizes acrylic resins with nano-chitosan particles is proposed. Therefore, we aimed to study the inhibitory effect of nano-chitosan particles on the biofilm formation of Candida species in acrylic resins.

Materials and Methods:

In this analytical in-vitro study, acrylic resins with nano-chitosan particles with concentrations of 0, 1%, 5%, and %10 were put adjacent to the suspension of Candida cells isolated from the individuals’ mouth and biofilm formation on resins was measured and compared. Finally, the data were analyzed using Kruskal-Wallis and Chi-square tests.

Results:

The observed differences between unmodified acrylic resin (control) and acrylic resin with nano-chitosan particles in terms of biofilm formation were significant (P<0.05) but no significant difference was found in the formation of biofilm species on resins.

Conclusion:

Biofilm formation of Candida species depends on acrylic resin type, in a way that by adding nano-chitosan particles to acrylic resins, biofilm formation of Candida species was significantly reduced. To decrease the organization of biofilm and denture stomatitis, the use of acrylics with nano-chitosan particles in producing dentures is recommended.

Photodynamic therapy as an antifungal treatment

Photodynamic therapy (PDT) involves the systemic or topical application of a photosensitizer (PS), alongside the selective illumination of the target lesion with light of an appropriate wavelength, in order to promote localized oxidative photodamage and subsequent cell death. Numerous studies have demonstrated that PDT is highly effective in the destruction of fungi in vitro. The mechanism underlying the effects of PDT results from the photons of visible light of an appropriate wavelength interacting with the intracellular molecules of the PS. Reactive species are produced as a result of the oxidative stress caused by the interaction between the visible light and the biological tissue. At present, no antifungal treatment based on PDT has been licensed. However, antifungal PDT is emerging as an area of interest for research.

Sensitivity of clinical isolates of Candida to essential oils from Burseraceae family

The aim of this study was to investigate the chemical composition and antifungal activity of four commercial essential oils from the Burseraceae family - two Boswellia carterii Flueck oils, Canarium luzonicum (Blume) A. Gray oil, and Commiphora myrrha (Nees) Engl oil, against most common Candida spp. recovered from the human oral cavity. The essential oil samples were analyzed by GC-FID and GC/MS. The analysis showed that major essential oils' components were α-pinene (23.04 % and 31.84 %), limonene (45.62 %) and curzerene (34.65 %), respectively. Minimum inhibitory (MIC) and minimum fungicidal (MFC) concentrations were determined using a microdilution standardized technique. All tested Candida spp. clinical isolates and ATCC strains showed susceptibility to tested essential oils in a dose dependent manner. The strongest antifungal activity was shown by essential oil of B. carterii, sample 2; the average MIC values ranged from 1.25 to 1.34 mg/ml, and MFC values ranged from 2.50 to 3.75 mg/ml, depending on the fungus. This study supports the possible use of essential oils from the Bursecaceae family in reduction and elimination of Candida spp. populations in patients with oral cavity fungal infections.

Antifungal prescribing pattern and attitude towards the treatment of oral candidiasis among dentists in Jordan

AIM

The aim of this study was to evaluate the attitude of Jordanian dentists towards the treatment of oral candidiasis and their current antifungal prescribing habits, shedding more light on the possible influence of their socio-professional factors on the pattern of prescribing and practice.

METHODS

A structured validated questionnaire was developed and tested; it was then emailed to a random sample of 600 Jordanian dental practitioners during the period of this cross-sectional survey. The questionnaire recorded practitioners' personal details and their attitude and prescribing of antifungal therapy for oral candidiasis. Statistical significance was based on probability values of <0.05 and was measured using the chi-square and Fisher's exact tests. Multiple logistic regression analysis was used to analyse the influence of respondents' socio-professional factors on their attitude towards oral candidiasis.

RESULTS

Of the 423 questionnaires returned, only 330 were included. The attitude of respondents was significantly influenced by their experience [odds ratio (OR) = 0.14; P < 0.001] and workplace (OR = 4.70; P < 0.001). Nystatin was the most commonly prescribed antifungal agent (78.2%), followed by miconazole (62.4%), which was prescribed for topical use. Systemic antifungals were prescribed by 21.2% of respondents, with a significant (P < 0.05) association with the country in which their qualification was obtained.

CONCLUSION

The attitude towards the treatment of oral candidiasis is much better among the least-experienced dentists working in private practice. Nystatin and miconazole are the most popular choices of antifungal agents among Jordanian dentists.

Candida-streptococcal mucosal biofilms display distinct structural and virulence characteristics depending on growth conditions and hyphal morphotypes

Candida albicans and streptococci of the mitis group form communities in multiple oral sites, where moisture and nutrient availability can change spatially or temporally. This study evaluated structural and virulence characteristics of Candida-streptococcal biofilms formed on moist or semidry mucosal surfaces, and tested the effects of nutrient availability and hyphal morphotype on dual-species biofilms. Three-dimensional models of the oral mucosa formed by immortalized keratinocytes on a fibroblast-embedded collagenous matrix were used. Infections were carried out using Streptococcus oralis strain 34, in combination with a C. albicans wild-type strain, or pseudohyphal-forming mutant strains. Increased moisture promoted a homogeneous surface biofilm by C. albicans. Dual biofilms had a stratified structure, with streptococci growing in close contact with the mucosa and fungi growing on the bacterial surface. Under semidry conditions, Candida formed localized foci of dense growth, which promoted focal growth of streptococci in mixed biofilms. Candida biofilm biovolume was greater under moist conditions, albeit with minimal tissue invasion, compared with semidry conditions. Supplementing the infection medium with nutrients under semidry conditions intensified growth, biofilm biovolume and tissue invasion/damage, without changing biofilm structure. Under these conditions, the pseudohyphal mutants and S. oralis formed defective superficial biofilms, with most bacteria in contact with the epithelial surface, below a pseudohyphal mass, resembling biofilms growing in a moist environment. The presence of S. oralis promoted fungal invasion and tissue damage under all conditions. We conclude that moisture, nutrient availability, hyphal morphotype and the presence of commensal bacteria influence the architecture and virulence characteristics of mucosal fungal biofilms.

Assessment of Candida species colonization and denture-related stomatitis in bar- and locator-retained overdentures

The aim of this study was to assess the prevalence of denture-related stomatitis (DRS) in different attachment-retained overdenture wearers and its association with particular colonizing Candida species. Thirty-seven edentulous patients with implant-supported maxillary or mandibular overdentures were enrolled. A full clinical history was obtained, including details of patients' oral hygiene practices and the levels of erythema based on Newton's classification scale. Swabs were taken from the palate and investigated mycologically to identify the yeast colonies. Quantitative and qualitative microbiological assessments were performed, which included recording the total numbers of colonies (cfu), their color, and their morphological characteristics. Significant differences were found in cfu values between the attachment and inner surfaces of locator- and bar-retained overdentures (P < .05). Candida albicans was the most common species in both evaluations, being isolated from 81.3% of bar-retained overdentures and 38.1% of locator-retained overdentures. DRS developed in all patients using bar-retained overdentures but in only 71.4% of those using locator-retained overdentures. No statistically significant relationship was found between bar and locator attachments according to smoking habit, overnight removal, or plaque and gingival indices (P > .05).

In vitro antifungal evaluation of seven different disinfectants on acrylic resins

Objective. The aim of this study was to evaluate alternative methods for the disinfection of denture-based materials. Material and Methods. Two different denture-based materials were included in the study. Before microbial test, the surface roughness of the acrylic resins was evaluated. Then, the specimens were divided into 8 experimental groups (n = 10), according to microorganism considered and disinfection methods used. The specimens were contaminated in vitro by standardized suspensions of Candida albicans ATCC#90028 and Candida albicans oral isolate. The following test agents were tested: sodium hypochlorite (NaOCl 1%), microwave (MW) energy, ultraviolet (UV) light, mouthwash containing propolis (MCP), Corega Tabs, 50% and 100% white vinegar. After the disinfection procedure, the number of remaining microbial cells was evaluated in CFU/mL. Kruskal-Wallis, ANOVA, and Dunn's test were used for multiple comparisons. Mann Whitney U test was used to compare the surface roughness. Results. Statistically significant difference (P < 0.05) was found between autopolymerised and heat-cured acrylic resins. The autopolymerised acrylic resin surfaces were rougher than surfaces of heat-cured acrylic resin. The most effective disinfection method was 100% white vinegar for tested microorganisms and both acrylic resins. Conclusion. This study showed that white vinegar 100% was the most effective method for tested microorganisms. This agent is cost-effective and easy to access and thus may be appropriate for household use.

Mycological analysis of the oral cavity of patients using acrylic removable dentures

Background. The problems of fungal infections in edentulous have been discussed in literature. Findings show that oral mycosis has an influence on the mycosis of oesophageal mucosa. Based on this we started to follow from 2007 in patients who wear dentures mycological examination, to evaluate changes of yeasts numbers, the sensitivity to antibiotics and determine the impact of types of prosthesis, time of using, gender and age of patients. 1230 patients who were wearing dentures participated in the retrospective study. The material for mycological examination was sampled as a smear from the palate. After the mycological identification of Candida species and assessment of growth, the susceptibility testing with Fluconazole and Nystatin was made. The number of 23 Candida species was diagnosed microbiologically in five years. C. albicans and C. glabrata were increasing in number—from 33,7% to 46,9% and 6,7% to 14,0%, respectively. There was a significant statistical difference between yeasts growth and gender (P = 0, 017 < 0.05). The conclusion is that a large percentage of persons wearing removable denture has been affected by Candida species and that could lead to the mycosis of farther gastrointestinal tract sections. The mycological examination before treatment, especially in patients using acrylic denture, appears to be necessary.

Hosting infection: experimental models to assay Candida virulence

Although normally commensals in humans, Candida albicans, Candida tropicalis, Candida parapsilosis, Candida glabrata, and Candida krusei are capable of causing opportunistic infections in individuals with altered physiological and/or immunological responses. These fungal species are linked with a variety of infections, including oral, vaginal, gastrointestinal, and systemic infections, with C. albicans the major cause of infection. To assess the ability of different Candida species and strains to cause infection and disease requires the use of experimental infection models. This paper discusses the mucosal and systemic models of infection available to assay Candida virulence and gives examples of some of the knowledge that has been gained to date from these models.

Effectiveness of photodynamic therapy for the inactivation of Candida spp. on dentures: in vitro study

OBJECTIVE

This in vitro study evaluated the effectiveness of photodynamic therapy (PDT) for the inactivation of different species of Candida on maxillary complete dentures.

BACKGROUND DATA

The treatment of denture stomatitis requires the inactivation of Candida spp. on dentures. PDT has been reported as an effective method for Candida inactivation.

METHODS

Reference strains of C. albicans, C. glabrata, C. tropicalis, C. dubliniensis and C. krusei were tested. Thirty-four dentures were fabricated in a standardized procedure and subjected to ethylene oxide sterilization. The dentures were individually inoculated with one of the strains and incubated at 37°C for 24 h. Dentures submitted to PDT (P+L+) were individually sprayed with 50 mg/L of Photogem(®) (PS) and, after 30 min, illuminated by LED light for 26 min (37.5 J/cm(2)). Additional dentures were treated only with PS (P+L-) or light (P-L+) or neither (P-L-). Samples of serial dilutions were spread on Sabouraud dextrose agar and incubated at 37°C for 48 h. The colonies were counted and the values of log (cfu/mL) were analyzed by Kruskall-Wallis and Dunn tests (p<0.05).

RESULTS

For all species of Candida, PDT resulted in significant reduction (p<0.05) of cfu/mL values from dentures when compared with P-L- (reductions from 1.73 to 3.99 log(10)). Significant differences (p<0.05), but lower reductions, were also observed for P+L- and P-L+when compared with P-L- for some species of Candida.

CONCLUSIONS

PDT was an effective method for reducing Candida spp. on dentures.

Denture stomatitis treated with photodynamic therapy: five cases

OBJECTIVE

Photodynamic therapy (PDT) is an effective method for Candida spp. inactivation in vitro and in vivo, but as yet, no clinical trial has been conducted. This report describes 5 cases of denture stomatitis (DS) treated with PDT.

STUDY DESIGN

Five subjects with clinical and microbiologic diagnosis of DS were submitted to 6 sessions of PDT 3 times a week for 15 days. In each session, patients' dentures and palates were sprayed with 500 mg/L Photogem, and, after 30 minutes of incubation, irradiated by light-emitting diode light source at 455 nm (37.5 and 122 J/cm(2), respectively). Cultures of Candida spp. from dentures and palates and standard photographs of the palates were taken at baseline (day 0), at the end of the treatment (day 15), and at follow-up time intervals (days 30 and 60).

RESULTS

Four patients showed clinical resolution of DS (no inflammation) after PDT sessions, and only 1 subject demonstrated reduction in palatal inflammation. Recurrence of DS was observed in 2 patients during the follow-up period.

CONCLUSIONS

PDT appears to be an alternative treatment for DS.

Use of antifungal agents for oral candidiasis: results of a national survey

BACKGROUND

Candida albicans is an opportunistic agent that colonizes the oral mucosa.

OBJECTIVES

To determine the attitude of Spanish dentists toward the oral treatment of candidiasis.

METHOD

Between May and November 2006, a questionnaire was circulated to a random selection of 1134 dentists obtained from the General Dental Council's main list. The survey consisted of a block of socio-demographic items followed by another block related to the diagnosis and treatment of oral candidiasis. Replies to the questionnaire were received from 840 (74%) dentists.

RESULTS

50.4% of respondents were men, and 48.1% were female with a mean age of 38 and 12.2 years of professional experience. Miconazole was the most popular choice of antifungal agent prescribed (59.3%), followed by nystatin (57.7%) for topical use. Systemic antifungal agents were used by 30.20% of dentists, with a strong association between their use and the number of years in practice, gender and professional qualifications (P < 0.005).

CONCLUSION

Most Spanish dentists make clinical diagnosis and treat oral infections by C. albicans themselves with topical drugs (miconazole and nystatin) as a first choice. Systemic treatments are more commonly chosen by male dentists with long professional experience, especially by stomatologists.

Periodontal conditions, oral Candida albicans and salivary proteins in type 2 diabetic subjects with emphasis on gender

Background

The association between periodontal conditions, oral yeast colonisation and salivary proteins in subjects with type 2 diabetes (T2D) is not yet documented. The present study aimed to assess the relationship between these variables in type 2 diabetic subjects with reference to gender.

Methods

Fifty-eight type 2 diabetic subjects (23 males and 35 females) with random blood glucose level ≥ 11.1 mmol/L were investigated. Periodontal conditions (plaque index [PI], bleeding on probing [BOP], probing pocket depth [PD] (4 to 6 mm and ≥ 6 mm), oral yeasts, salivary immunoglobulin (Ig) A, IgG and total protein concentrations, and number of present teeth were determined.

Results

Periodontal conditions (PI [p < 0.00001], BOP [p < 0.01] and PD of 4 to 6 mm [p < 0.001], salivary IgG (μg)/mg protein (p < 0.001) and salivary total protein concentrations (p < 0.05) were higher in type 2 diabetic females with Candida albicans (C. albicans) colonisation compared to males in the same group. Type 2 diabetic females with C. albicans colonisation had more teeth compared to males in the same group (p < 0.0001).

Conclusion

Clinical and salivary parameters of periodontal inflammation (BOP and IgG (μg)/mg protein) were higher in type 2 diabetic females with oral C. albicans colonisation compared to males in the same group. Further studies are warranted to evaluate the association of gender with these variables in subjects with T2D.

Occurrence, isolation and differentiation of Candida spp. and prevalence of variables associated to chronic atrophic candidiasis

The purpose of this study was to survey the frequency of Candida spp. in patients with chronic atrophic candidiasis (CAC), to differentiate Candida species and to assess the prevalence of certain infection-associated variables to this disease. Patients with CAC and wearing partial or complete dentures were recruited. Data were obtained by means of a questionnaire with details involving identification of the subject, demographic characteristics, behaviour and medical history, clinical and mycological evaluation and identification of yeast. The sample collection was carried out in the palate or palate and tongue of the subjects using sterilised swabs. Data were submitted to statistical analyses using Fischer's test. Forty-three (53%) cases of CAC showed the presence of Candida albicans. Females (75.2%) wearing complete dentures (60.1%) for more than 10 years (58%) were risk factors to CAC development. It could be concluded that: (a) the results did not confirm a significant difference among patients with CAC concerning the presence or absence of Candida spp.; (b) the occurrence of Candida was negatively related to important factors associated to this opportunistic infection; and (c) mycological findings did not indicate that the variables investigated have a significant effect on oral infections by C. albicans or other Candida species.

Antifungal suscepitibility profile of candida spp. oral isolates obtained from denture wearers

Denture stomatitis is an inflammatory condition that occurs in denture wearers and is frequently associated with Candida yeasts. Antifungal susceptibility profiles have been extensively evaluated for candidiasis patients or immunosupressed individuals, but not for healthy Candida carriers. In the present study, fluconazole, itraconazole, voriconazole, terbinafine and 5-flucytosin were tested against 109 oral Candida spp. isolates. All antifungal agents were effective against the samples tested except for terbinafine. This work might provide epidemiological information about Candida spp. drug susceptibility in oral healthy individuals.

Denture contamination by yeasts in the elderly

OBJECTIVES

The aim of this study was to investigate yeast carriage in healthy denture wearers by swabbing and to evaluate the effect of denture hygiene habits.

MATERIALS AND METHODS

Denture wearers (n = 87) without evidence of denture stomatitis or any other oral disease were investigated by separately swabbing the fitting surface of the upper denture and the corresponding palatal mucosa in contact with the appliance. In a group of volunteers, a gel without any active compound was spread on the palatal side of the denture once in every morning for 2 weeks.

RESULTS

Screening showed Candida colonisation of upper prosthesis in 75.9% of individuals. The most frequent species isolated were Candida albicans (77.9% of the positive cultures), Candida glabrata (44.1%) and Candida tropicalis (19.1%). Carriage of more than one yeast species was found in 48.5% of the contaminated dentures. There was a statistically significant association between denture contamination and palatal mucosa colonisation (chi-squared test: p < 0.0001). Repeated swabbings after 1 week as well as during a weekly follow-up for 1 month confirmed the denture contamination and its degree of severity. A daily gel application produced a yeast-count decrease to 10% of the initial value after 2 weeks (chi-squared test: p = 0.0134 and p = 0.2841 for prosthesis and palatal mucosa, respectively).

CONCLUSION

This study documented the reliability of oral swabbing when investigating yeast carriage in healthy denture wearers. Moreover, just a diagnostic tool, sampling upper dentures for Candida could be the opportunity to verify the patient's compliance to hygiene advice.