Comparison of denture microwave disinfection and conventional antifungal therapy in the treatment of denture stomatitis: a randomized clinical study

Current Drug Delivery Strategies for Buccal Cavity Ailments using Mouth Dissolving Wafer Technology: A Comprehensive Review on the Present State of the Art

BACKGROUND

Mouth-dissolving wafer is polymer-based matrice that incorporates various pharmaceutical agents for oral drug delivery. This polymeric wafer is ingenious in the way that it needs not be administered with water, like in conventional tablet dosage form. It has better compliance among the pediatric and geriatric groups owing to its ease of administration.

OBJECTIVE

The polymeric wafer dissolves quickly in the oral cavity and is highly effective for a targeted local effect in buccal-specific ailments. It is a safe, effective, and versatile drug delivery carrier for a range of drugs used to treat a plethora of oral cavity-specific ailments that inflict common people, like thrush, canker sores, periodontal disease, benign oral cavity tumors, buccal neoplasm, and malignancies. This review paper focuses thoroughly on the present state of the art in mouth-dissolving wafer technology for buccal drug delivery and targeting. Moreover, we have also addressed present-time limitations associated with wafer technology to aid researchers in future developments in the arena of buccal drug delivery.

CONCLUSION

This dynamic novel formulation has tremendous future implications for designing drug delivery systems to target pernicious ailments and diseases specific to the buccal mucosa. In a nutshell, this review paper aims to summarize the present state of the art in buccal targeted drug delivery.

Comparative effectiveness of interventions for the treatment of denture stomatitis: A systematic review with network meta-analysis

STATEMENT OF PROBLEM

Symptomatic denture stomatitis (DS) is a painful oral mucosal disorder that can impair quality of life in denture wearers. A complete cure of DS is difficult to achieve, and the most efficacious regimen to treat DS has not yet been conclusively established.

PURPOSE

The purpose of this network meta-analysis was to assess the comparative efficacy of interventions used for the treatment of DS.

MATERIAL AND METHODS

A search was conducted for trials published in Medline, Scopus, PubMed, and Cochrane Central Register of Controlled Trials from inception until February 2022 (PROSPERO Reg no: CRD42021271366). Network meta-analysis was performed on data from randomized controlled trials that assessed the comparative efficacy of any form of intervention for the treatment of DS in denture wearers. Agents were ranked according to their effectiveness in the treatment of DS based on outcomes using surface under the cumulative ranking (SUCRA).

RESULTS

A total of 25 articles were included in the quantitative analysis. Topical antifungal agents (risk ratio [RR]=4.37[95% confidence interval [CI]: 2.15,8.90), topical antimicrobial agents used along with systemic antifungal agents (RR=4.25[95% CI: 1.79,10.33]), systemic antifungal agents (RR=4.25[95% CI: 1.79,10.10]), photodynamic therapy (RR=4.25[95% CI: 1.75,8.98]), and topical plant products (RR=3.40[95% CI: 1.59,7.26]) were found to effectively improve DS. Microwave disinfection concurrently administered with topical antifungal agents (RR=7.38(95% CI: 2.75,19.81), microwave disinfection 7.38[95% CI: 2.75,19.81]), topical antifungal agents (RR=4.88[95% CI: 1.92,12.42]), topical plant products (RR=4.49[95% CI: 1.70,11.82]), systemic antifungal agents together with topical antimicrobial agents (RR=3.85[95% CI: 1.33,11.10]), topical antimicrobial agents (RR=3.39[95% CI: 1.17,9.81]), systemic antifungal agents (RR=3.37[95% CI: 1.21,9.34]), and photodynamic therapy or photochemotherapy (PDT) (RR=2.93[95% CI: 1.01,8.47]) were found to effectively resolve mycological DS. Topical antifungals ranked highest in the SUCRA ranking for clinical improvement, whereas microwave disinfection concurrently administered with topical antifungal agents ranked highest for mycological resolution. None of the agents demonstrated significant side effects except for topical antimicrobial agents which demonstrated altered taste and staining of oral structures.

CONCLUSIONS

Available evidence suggests that topical antifungals, microwave, and systemic antifungals are effective in the treatment of DS, but confidence in these findings is low because of the limited number of studies and a high risk of bias. Additional clinical trials are needed on photodynamic therapy, topical plant products, and topical antimicrobials.

Nystatin Effectiveness in Oral Candidiasis Treatment: A Systematic Review & Meta-Analysis of Clinical Trials

Oral candidiasis is the most common opportunistic fungal infection caused by commensal Candida species. Since there are various local and systemic predisposing factors for the disease, the treatment also varies from topical to systemic antifungal agents. Nystatin is a common antifungal agent used topically. The aim of this systematic review was to evaluate and compare the efficacy of different antifungal agents and the safety of nystatin in the treatment of oral candidiasis. Three electronic databases were searched for randomized controlled trials comparing nystatin with other anti-fungal therapies or placebo. Clinical and/or mycological cure was the outcome evaluation. A meta-analysis and descriptive study on the efficacy, treatment protocols, and safety of nystatin was also conducted. The meta-analysis included five studies, which compared the efficacy of nystatin suspensions with photodynamic therapy. A significant difference in the colony-forming units per milliliters (CFU/mL) of Candida species was observed at 60 days intervals for both palatal mucosa and denture surfaces, with both groups favoring nystatin with low heterogeneity at a 95% confidence interval. Nystatin and photodynamic therapy were found to be equally effective for the clinical remission of denture stomatitis as well as a significant reduction of CFU/mL of Candida species from dentures and palatal surfaces of the patients.

Resilient liner modified by antimicrobials for denture stomatitis treatment: A randomized controlled trial

OBJECTIVES

This randomized clinical trial evaluated the effectiveness of an interim denture resilient liner (Trusoft) modified with minimum inhibitory concentrations (MICs) of antimicrobial agents for Candida albicans biofilm in the denture stomatitis (DS) treatment.

METHODS

Forty participants with DS and maxillary complete denture (MCD) wearers were randomly assigned to one of the treatments for 14 days (n=10): nystatin oral suspension (Control-100,000IU/mL; 4 × /day), MCD relined with Trusoft either without (Tru) or with nystatin (Ny) or chlorhexidine diacetate (Chx) at MICs. Cytological smears and mycological quantitative cultures were taken from the palate and denture before treatment (baseline), at the end of treatment (day 14), and at follow-up (days 30, 45, and 60). Photographs of the palate were made at each visit. Data were analyzed by the Cochran and χ² tests, ANOVA and the Tukey test or the Friedman and Kruskal-Wallis tests (α=0.05).

RESULTS

Palatal smears of the Ny and Chx groups exhibited no mycelial Candida (0%) on day 14, and, at the 60-day follow-up, it was observed for only 1 participant from Chx group. MCD smears showed reduction in mycelial forms for all groups on day 14 (P<0.05), but this difference was maintained at follow-up only for the relined dentures (P<0.05). Unlike Tru and the control groups, Ny and Chx groups evidenced a significant reduction in CFU/mL values and DS severity throughout the trial (P<0.05).

CONCLUSIONS

The addition of nystatin and chlorhexidine at MICs to an interim resilient liner is a promising treatment for DS, with better results than those for conventional therapy with nystatin suspension, including the follow-ups.

CLINICAL SIGNIFICANCE

Compared with conventional topical antifungal therapy, modifying a denture reline material with antimicrobials provided a therapeutic option for denture stomatitis. This non-invasive, straightforward therapeutic approach can be easily adopted by dentists and has the advantage of not requiring patient compliance while maintaining therapeutic concentrations on the denture base.

A modified Newton classification for denture stomatitis

The effectiveness of denture stomatitis (DS) treatment should be evaluated by associating clinical and mycological parameters. Although widely used in clinical studies, the Newton classification does not accurately represent the degree of severity of palatal inflammation in terms of extent of the lesions and intensity of the erythema. Therefore, a modified Newton classification has been proposed considering the coverage area of palatal inflammation and the erythema level. This consistent and direct ranking will help standardise randomised clinical trials, as well as the statistical comparison among blind evaluations of the obtained scores within and between studies.

CLEANING OF REMOVABLE DENTAL PROSTHESES - A SYSTEMATIC REVIEW

Objectives The aim of this systematic review was to provide an overview of the scientific evidence available from prospective clinical studies regarding denture hygiene interventions. Therefore, investigations addressing the efficacy of removing microorganisms and biofilms formed on the surface of removable dental prostheses (RDPs) and denture base materials in situ and their impact on the properties of denture base materials, such as color stability, surface roughness, and dimensional stability, were included. Methods A systematic literature search was conducted from June 1975-May 2020 and included articles published in English that have been indexed in the digital archives of PubMed and Cochrane (including PubMed, Embase, ICTRP, CT.gov). A complementary manual search of the initially retrieved studies was conducted. Inclusion criteria comprised prospective clinical trials with a minimum of ten participants investigating (1) approaches and methods to remove biofilms formed on the surface of RDPs and denture base materials in situ and/or (2) the influence of these biofilms on denture base materials. A total of forty-four studies were included in this systematic review, which was registered in the PROSPERO database (CRD42020189649). Results and Conclusions Data gathered from the systematic review indicate that the combined use of chemical and mechanical denture hygiene interventions is significantly more effective than single cleaning approaches. Only limited evidence is available from clinical studies regarding the effect of denture hygiene interventions on the properties of denture base materials.

Does microwave disinfection affect the dimensional stability of denture base acrylic resins? A systematic review

OBJECTIVE

To systematically evaluate the effect of microwave disinfection on the dimensional stability of denture base acrylic resins.

BACKGROUND

Microwave disinfection has been considered as an alternative method for disinfecting complete dentures to help prevent and treat denture stomatitis. However, data on the impact of microwave disinfection on the dimensional stability of acrylic resins are still scarce.

METHODS

The PubMed/Medline, SCOPUS and EMBASE databases were searched in order to assess articles published in English up to January 2021 (CRD42021212267). We included studies that have assessed the effect of microwave disinfection, on the dimensional stability of acrylic resins, comparing them with negative or positive controls.

RESULTS

A total of seven in vitro studies were included. The qualitative synthesis demonstrated that, in general, microwave disinfection produced more distortion on the materials than do immersion in sodium hypochlorite, chloride solution, chlorhexidine, and water immersion. However, considering the dimensional stability of the specimens, microwave disinfection at 500 W for 3 minutes, and at 450 W for 5 minutes, produced similar or better outcomes than did control groups.

CONCLUSION

In general, microwave disinfection promotes changes in the dimensional stability of denture base acrylic resins, and should thus be used with caution. However, microwave disinfection protocols at lower power settings (500 and 450 W) and exposure times (3 and 5 minutes) produces similar or less distortion than chemical disinfection. More studies are still required in order to evaluate the clinical and long-term implications of microwave disinfection.

Fungal Infections of Oral Cavity: Diagnosis, Management, and Association with COVID-19

The frequency of fungal infections is increasing due to immunodeficiency viruses and immunosuppressive drugs. The most common fungal infection of the oral cavity is candidiasis. The existence of Candida can be a part of normal commensal; hence, the isolation of Candida in the absence of clinical symptoms should exclude candidiasis. The pathogenicity of Candida is witnessed as opportunistic when immune status is compromised. Oral fungal infections are uncommon, but when identified, these infections are associated with greater discomfort and are sometimes destruction of tissues. Cytology and tissue biopsy are helpful in confirming the clinical diagnosis. The management of oral fungal infections must strategically focus on signs, symptoms, and culture reports. This article reviews information on diagnosis and therapeutic management of aspergillosis, cryptococcosis, histoplasmosis, blastomycosis, mucormycosis, and geotrichosis.

Therapeutic Role of Nystatin Added to Tissue Conditioners for Treating Denture-Induced Stomatitis: A Systematic Review

Denture-induced stomatitis (DIS) represents a pathological condition caused by ill-fitting dentures trauma, manifested as inflammation of the palatal tissue beneath the denture. The fungal infections are the principal contributory factors to DIS. Although the aetiology of DIS is multifactorial, the Candida albicans fungal infection remains the main cause. The objective of the present systematic review was to evaluate the latest literature on the addition of nystatin into the tissue conditioners (TCs) in the management of DIS. To search the published literature about “the addition of nystatin in TCs for treating DIS”, electronic databases (PubMed (National library of medicine) and Cochrane Library (Wiley)) were searched (from 1975 until December 2020) using different keywords. Various studies described the effectiveness and efficacy of incorporating nystatin into several TCs. The present systematic review reported that the addition of nystatin is beneficial, with slight or no consequences on both the mechanical and physical features of TCs. Adding nystatin to various TCs for treating DIS can be suggested.

Effect of zinc oxide nanoparticles incorporated into tissue conditioner on antifungal, physical, and mechanical properties

This study evaluated the antifungal, physical, and mechanical properties of tissue conditioner incorporated with different amounts of zinc oxide nanoparticles (ZnOnps) at different storage times (0, 7, and 14 days). Specimens of 0, 5, 10, 15 wt% ZnOnps, or 15 wt% nystatin incorporated into tissue conditioner were fabricated (control, 5Zn, 10Zn, 15Zn, and Nys). The direct contact test (n=6) was performed to evaluate the antifungal effect against C. albicans suspension. The penetration depth (n=6) and tensile bond strength (n=8) were evaluated following ISO 13139. The 15Zn significantly reduced C. albicans cell number compared with control at all storage times (p<0.001). The penetration depths and tensile bond strengths of the 5Zn, 10Zn, 15Zn, and Nys were not significantly different compared with control at all storage times (p>0.05). In conclusion, the 15Zn provides antifungal effect up to 14 days without adverse effects on penetration depth and tensile bond strength.

Microbial interactions and immunity response in oral Candida species

Oral candidiasis are among the most common noncommunicable diseases, related with serious local and systemic illnesses. Although these infections can occur in all kinds of patients, they are more recurrent in immunosuppressed ones such as patients with HIV, hepatitis, cancer or under long antimicrobial treatments. Candida albicans continues to be the most frequently identified Candida spp. in these disorders, but other non-C. albicans Candida are rising. Understanding the immune responses involved in oral Candida spp. infections is a key feature to a successful treatment and to the design of novel therapies. In this review, we performed a literature search in PubMed and WoS, in order to examine and analyze common oral Candida spp.-bacteria/Candida-Candida interactions and the host immunity response in oral candidiasis.

Effectiveness of denture microwave disinfection for treatment of denture stomatitis: A systematic review and meta-analysis

OBJECTIVE

The aim of this systematic review was to evaluate the effectiveness of removable complete denture disinfection using microwaves for the treatment of denture stomatitis.

METHODS

This review identified studies comparing the efficacy of microwave prosthesis disinfection (I) to topical antifungal therapy (C) in the treatment of denture stomatitis (O), which included only individuals who used complete dentures and presented with denture stomatitis (P). The search was performed in six databases and identified 1524 records; after the removal of duplicates, 816 articles remained. Three articles were selected for qualitative synthesis and two for meta-analysis. Random-effects meta-analysis estimated the polled effects of microwave disinfection and antifungal therapy on the Candida counts and clinical manifestation of denture stomatitis. The GRADE approach was used to estimate the certainty of evidence.

RESULTS

All included studies reported significant reductions in Candida counts and the frequency of denture stomatitis of groups subjected to microwave disinfection of dentures and topical antifungal therapy with nystatin. Significative differences between treatments were only detected for Candida quantification in the palate, within 90 days follow-up period (SMD = 0.47, 95% CI = 0.02-0.91). Meta-analyses did not show any further differences between treatments (p > .05), considering the Candida quantification in dentures and the frequency of clinical signs of denture stomatitis. The certainty of the evidence was considered as low, according to GRADE approach.

CONCLUSION

Microwave disinfection of complete dentures can be considered as efficient as antifungal therapy for the treatment of denture stomatitis. However, further well-designed studies are necessary to confirm such evidence.

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

OBJECTIVE

To evaluate the effectiveness of microwave disinfection in treating Candida-associated denture stomatitis (CADS).

MATERIALS AND METHODS

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.

RESULTS

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).

CONCLUSION

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.

CLINICAL RELEVANCE

Our findings provide evidence regarding the treatment of CADS using microwave disinfection, and also indicating the best cost-effective option for this treatment modality.

Antifungal effect of tea extracts on Candida albicans

Determining whether tea extracts are effective in removing Candida albicans (C. albicans) from dentures is of interest. This study aimed to investigate the antifungal effect of tea extracts on C. albicans. One green tea (Anji white tea, AGW) and 2 oolong teas (Tie Guan Yin, TGY; Da Hong Pao, DHP) of different concentrations were tested. C. albicans suspensions were inoculated on the plates and the numbers of colony-forming units (CFU) in the culture medium were used to screen for the optimum tea extracts. Polymethyl methacrylate (PMMA) specimens that contained C. albicans biofilms were then treated with the tea extracts and the numbers of CFU were counted. The antifungal activities of the tea extracts were not significantly correlated with their catechin concentrations. Although AGW at 10.0 mg/mL and DHP at 2.5 mg/mL significantly inhibited C. albicans in the culture medium, the extracts failed to exert inhibitory effects against C. albicans biofilms on the PMMA surfaces.

Guanidine derivative inhibits C. albicans biofilm growth on denture liner without promote loss of materials' resistance

To reduce the burden of denture stomatitis and oral candidiasis, an aqueous solution containing polyhexamethylene guanidine hydrochloride (PHMGH) was investigated as an antifungal disinfectant against the leading cause of these oral conditions, Candida albicans. The solutions formulated with concentrations ranging from 0.125 to 0.50 wt% enabled increasing disinfection at the initial 5min-contact with 72h-mature candida biofilms formed on denture liner specimens. After 10 min-contact, the solution at lower concentration has reached total fungal elimination. The results also indicated that the denture liners preserved their mechanical property after the maximum contact time with the solution at the highest tested concentration. The PHMGH aqueous solutions at 0.125 wt% could be applied to promote interim denture liner disinfection without promoting the loss of materials' mechanical property.

Candida sp. Infections in Patients with Diabetes Mellitus

Candidiasis has increased substantially worldwide over recent decades and is a significant cause of morbidity and mortality, especially among critically ill patients. Diabetes mellitus (DM) is a metabolic disorder that predisposes individuals to fungal infections, including those related to Candida sp., due to a immunosuppressive effect on the patient. This review aims to discuss the latest studies regarding the occurrence of candidiasis on DM patients and the pathophysiology and etiology associated with these co-morbidities. A comprehensive review of the literature was undertaken. PubMed, Scopus, Elsevier’s ScienceDirect, and Springer’s SpringerLink databases were searched using well-defined search terms. Predefined inclusion and exclusion criteria were applied to classify relevant manuscripts. Results of the review show that DM patients have an increased susceptibility to Candida sp. infections which aggravates in the cases of uncontrolled hyperglycemia. The conclusion is that, for these patients, the hospitalization periods have increased and are commonly associated with the prolonged use of indwelling medical devices, which also increase the costs associated with disease management.

Curcumin-mediated anti-microbial photodynamic therapy against Candida dubliniensis biofilms

The purpose of this study was to evaluate the effectiveness of anti-microbial photodynamic therapy (aPDT) mediated by curcumin (Cur) associated with LED light against biofilms of Candida dubliniensis, and further, investigate cellular uptake and drug penetration through the biofilms under confocal laser scanning microscopy (CLSM). Four C. dubliniensis strains were tested: three clinical isolates from HIV-positive patients and one reference strain (CBS 7987). Biofilms were treated with three Cur concentrations (20.0, 30.0, and 40.0 μM). All samples were incubated in the dark for 20 min and exposed to a 5.28 J/cm² of LED light fluence. Additional samples of each strain were treated either with Cur or LED light only. Control samples had neither Cur nor light. After aPDT, results were read using the XTT salt reduction method. The data were statistically analyzed by two-way ANOVA followed by Games-Howell post-hoc test (α = 0.05). Confocal laser scanning microscopy was used to verify both the uptake of Cur by yeast cells and its penetration through the biofilm. The results showed that aPDT promoted significant reduction on the metabolism of the biofilm-organized cells of C. dubliniensis. Further, while Cur was rapidly taken up by C. dubliniensis cells, a longer time interval was required to allow Cur penetration into biofilm cells. Based on these results, aPDT associating LED and Cur presents promising potential on fungal control of biofilms of C. dubliniensis.

Histotripsy Treatment of S. Aureus Biofilms on Surgical Mesh Samples Under Varying Pulse Durations

Prior studies demonstrated that histotripsy generated by high-intensity tone bursts to excite a bubble cloud adjacent to a medical implant can destroy the bacteria biofilm responsible for the infection. The goal of this paper was to treat Staphylococcus aureus (S. aureus) biofilms on surgical mesh samples while varying the number of cycles in the tone burst to minimize collateral tissue damage while maximizing therapy effectiveness. S. aureus biofilms were grown on 1-cm square surgical mesh samples. The biofilms were then treated in vitro using a spherically focused transducer (1.1 MHz, 12.9-cm focal length, 12.7-cm diameter) using either a sham exposure or histotripsy pulses with tone burst durations of 3, 5, or 10 cycles (pulse repetition frequency of 333 Hz, peak compressional pressure of 150 MPa, peak rarefactional pressure of 17 MPa). After treatment, the number of colony forming units (CFUs) on the mesh and the surrounding gel was independently determined. The number of CFUs remaining on the mesh for the sham exposure (4.8 ± 0.9-log₁₀) (sample mean ± sample standard deviation-log10 from 15 observations) was statistically significantly different from the 3-cycle (1.9 ± 1.5-log₁₀), 5-cycle (2.2 ± 1.1-log₁₀), and 10-cycle exposures (1 ± 1.5-log₁₀) with an average reduction in the number of CFUs of 3.1-log₁₀. The numbers of CFUs released into the gel for both the sham and exposure groups were the same within a bound of 0.86-log₁₀, but this interval was too large to deduce the fate of the bacteria in the biofilm following the treatment.

Clinical trial for evaluation of Ricinus communis and sodium hypochlorite as denture cleanser

Objective

This study evaluated Ricinus communis and sodium hypochlorite solutions in terms of biofilm removal ability, remission of candidiasis, antimicrobial activity, and participant satisfaction.

Material and Methods

It was conducted a controlled clinical trial, randomized, double-blind, and crossover. Sixty-four denture wearers with (n=24) and without candidiasis (n=40) were instructed to brush (3 times/day) and immerse their dentures (20 min/day) in different storage solutions (S1 / S2: 0.25% / 0.5% sodium hypochlorite; S3: 10% R. communis; S4: Saline).The trial period for each solution was seven days and a washout period of seven days was used before starting the use of another solution. The variables were analyzed at baseline and after each trial period. The biofilm of inner surfaces of maxillary dentures was disclosed, photographed, and total and dyed areas were measured (Image Tool software). The percentage of biofilm was calculated. Remission of candidiasis was assessed by visual scale and score were attributed. Antimicrobial activity was assessed by the DNA-Checkerboard hybridization method. Patient satisfaction was measured using a questionnaire.

Results

S1 (4.41±7.98%) and S2 (2.93±5.23%) were more effective then S3 (6.95±10.93%) in biofilm remotion(P<0.0001). All solutions were different from the control (11.07±11.99%). S3 was the most effective solution in remission of candidiasis (50%), followed by S1 (46%). Concerning antimicrobial action, S1/S2 were similar and resulted in the lowest microorganism mean count (P=0.04), followed by S3. No significant differences were found with patient's satisfaction.

Conclusions

10% R. communis and 0.25% sodium hypochlorite were effective in biofilm removal, causing remission of candidiasis and reducing the formation of microbial colonies in denture surfaces. All solutions were approved by patients.

Role of antifungal medicaments added to tissue conditioners: A systematic review

PURPOSE

The aim of this review is to investigate the current state of knowledge on the incorporation of antifungal agents into the tissue conditioners for the treatment of denture induced stomatitis.

STUDY SELECTION

Studies reporting the incorporation of antifungal/antimicrobial agents in to tissue conditioners were included in the review. In order to search the studies on the topic "incorporation of antifungal agents in tissue conditioners for the treatment of denture induced stomatitis" ISI web of science, PubMed/MEDLINE, and Google-Scholar databases were searched from 1970 up to and including July 2015 using various keywords such as antifungal agents, tissue conditioners, Candida albicans, denture stomatitis, etc.

RESULTS

Various studies reported the efficacy and effectiveness of adding conventional organic antifungal medicines (nystatin, azole group derivatives and chlorhexidine, antimicrobials/antifungals other than organic (silver zeolite, silver nano-particles, photo-catalysts and metallic oxides) and natural and herbal antimicrobials (tea tree oil, lemongrass essential oil and origanum oil) into various tissue conditioners. The review literature reported that incorporation of antifungal agents into tissue conditioners is effective with minimal or no effects on physical and mechanical properties of tissue conditioners.

CONCLUSIONS

Incorporation of different antifungal medicaments to commercially available tissue conditioners can be recommended for the management of denture induced stomatitis.

Effectiveness of Chemical and Microwave Disinfection on Denture Biofilm Fungi and the Influence of Disinfection on Denture Base Adaptation

The aims of this study were to evaluate the effectiveness of six disinfection methods and the influence of these methods on the adaptation of maxillary dentures. Acrylic resin specimens contaminated with fungi were exposed to the following disinfection treatments: 1. microwave oven (900 W) at full power for 5 min (with soaking the specimen in 250 ml water), 2. microwave oven at medium power for 5 min (with soaking the specimen in 250 ml water), 3. sodium hypochlorite 5.25 % for 5 min, 4. diluted sodium hypochlorite 1:420 for 5 h, 5. Chlorhexidine gluconate for 5 h, 6. effervescent tablets for 15 min, 7. soaking in 250 ml tap water for 15 min. Colony forming units (CFUs) of remaining cells were counted and compared with t test (p ≤ 0.05). Dimensional stability was evaluated using aluminum die simulating the maxillary edentulous arch. Posterior palatal gaps were measured. Data were analyzed using one-way ANOVA test and t test (p ≤ 0.05). Microwave irradiation (at full or medium power) and sodium hypochlorite 5.25 % for 5 min were able to reduce the CFUs of fungi by more than 4 log10 whereas diluted sodium hypochlorite, chlorhexidine gluconate, and effervescent tablets did not achieve a reduction of >2.8, 2.68 and 1.66, respectively. For dimensional stability test, t test revealed significant difference between control group and the microwave at full power group (p = 0.000). Within the limits of this study, microwave oven at medium power and sodium hypochlorite (5.25 %) are effective and safe methods of disinfecting removable dentures.

The effect of repeated microwave irradiation on the dimensional stability of a specific acrylic denture resin

PURPOSE

To determine the dimensional stability of a poly(methyl methacrylate) (PMMA) acrylic resin when subjected to multiple sessions of repeated microwave irradiation at power settings of 700 and 420 W.

MATERIALS AND METHODS

Twenty standardized denture bases were fabricated using a PMMA resin. Points of measurement were marked on each denture base with a standardized template, and the distances between points were recorded using a digital microscope. The denture bases were randomly placed into two experimental groups of 10 bases each. Individual denture bases were placed into a glass beaker containing 200 ml of room temperature deionized water and then exposed to either 700 or 420 W of microwave radiation for 3 minutes. The denture bases were allowed to cool to room temperature, and measurements between points were recorded. This process was carried out for two microwave periods with measurements being completed after each period. The data were then analyzed for any significant changes in distances between points using a Student's t-test.

RESULTS

All denture bases experienced 1.0 to 2.0 mm or approximately 3% linear dimensional change after each period of microwaving. Results were significant with all t-tests having values of p < 0.05.

CONCLUSION

This report showed that the denture bases deformed significantly under experimental conditions at either 700 W for 3 minutes in 200 ml of water or 420 W for 3 minutes in 200 ml of water.

Comparison of the efficacy of a novel sustained release clotrimazole varnish and clotrimazole troches for the treatment of oral candidiasis

OBJECTIVES

Candida albicans is a common fungal infection and is commensal in 40-65 % of healthy adults. The development and pharmacokinetics of a novel sustained release clotrimazole varnish (Clot-SRV) for topical oral use have been reported. The aim of this study was to compare the efficacy of this varnish with clotrimazole troche treatment of oral candidiasis.

MATERIALS AND METHODS

Of the 12 patients with denture stomatitis treated for 14 days, six used Clot-SRV (study group) and six clotrimazole troches (control). The patients were instructed to use Clot-SRV (50 mg of clotrimazole) once a day, and the control group was instructed to use five troches of 10 mg clotrimazole/day. Microbiological samples were obtained from saliva, buccal mucosa, palate, and denture. The degree of erythema was recorded at three time points, and subjective opinions noted using a questionnaire.

RESULTS

At the end of the study, the control group had relatively more cases of erythema on all examined surfaces; patients who applied the Clot-SRV had significantly lower levels of candida on the denture surfaces and in saliva, and had better compliance to the medication.

CONCLUSIONS

The novel clotrimazole sustained release varnish may be an important part of a new protocol for oral candidiasis, with improved clinical outcomes.

In vitro evaluation of the enzymatic activity profile of non-albicans Candida species isolated from patients with oral candidiasis with or without diabetes

OBJECTIVE

To evaluate the expression of phospholipase (PL) and secreted aspartyl proteinase (SAP) by Candida glabrata and C tropicalis obtained from the denture biofilms of healthy participants (16 isolates), patients with oral candidiasis with diabetes (10 isolates), and patients with oral candidiasis without diabetes (25 isolates).

STUDY DESIGN

After incubation, the supernatants and pellets of the isolates were used for the enzymatic assays and quantification of colony-forming units (CFU), respectively. Colorimetric tests were used with phosphatidylcholine as a substrate for PL and azocasein as a substrate for SAP, and the absorbances of the samples were measured. Enzymatic rates were calculated, and values were normalized by CFU. Results were analyzed with factorial analyses of variance (α = .05).

RESULTS

C tropicalis and C glabrata were proteolytic and phospholipolytic. The clinical sources of isolates had no significant effect on the enzymatic activities (P > .05). C tropicalis had significantly higher enzymatic activity for both PL and SAP (P < .001) than did C glabrata.

CONCLUSIONS

C tropicalis isolates produced significantly higher amounts of both enzymes than did the C glabrata isolates.

Enzymatic activity profile of a Brazilian culture collection of Candida albicans isolated from diabetics and non-diabetics with oral candidiasis

The secretion of hydrolytic enzymes is a fundamental virulence factor of Candida albicans to develop disease. The objective of this study was to characterise the virulence of 148 clinical isolates of C. albicans from oral candidiasis by assessing the expression of phospholipase (PL) and secreted aspartyl proteinase (SAP). Isolates were obtained from healthy subjects (HS) and diabetics (DOC) and non-diabetics with oral candidiasis (NDOC). An aliquot (5 μl) of each cell suspension was inoculated on PL and SAP agar plates and incubated. Enzymes secretion was detected by the formation of an opaque halo around the colonies and enzymatic activity (PZ) was determined by the ratio between colony diameter and colony diameter plus the halo zone. Statistical comparisons were made by a one-way anova followed by Tukey's post hoc test (α = 0.05). The clinical sources of C. albicans had significant effect (P < 0.001) on the PZ values of both enzymes. For PL, clinical isolates from NDOC and DOC had highest enzymatic activity than those from HS (P < 0.05), with no significant differences between them (P = 0.506). For SAP, C. albicans from NDOC showed the lower enzymatic activity (P < 0.001). There were no significant differences between isolates from HS and DOC (P = 0.7051). C. albicans isolates from NDOC and DOC patients showed an increased production of PL.

Effect of antimicrobial agents incorporated into resilient denture relines on the Candida albicans biofilm

OBJECTIVE

The antimicrobial action of five drugs incorporated in temporary denture relines on the fungal biofilm was evaluated.

MATERIALS AND METHODS

A Candida albicans biofilm (SC5314) was formed on specimens (10 × 1 mm) of materials (Trusoft and Softone) modified or not (control) by the drugs (nystatin, miconazole, ketoconazole, itraconazole, and chlorhexidine diacetate). Cell viability was determined spectrophotometrically by the tetrazolium salt reduction assay (XTT) after 24 h, 48 h, and 7 and 14 days of incubation. The minimum inhibitory concentrations (MICs) were those which inhibited 90% or more of fungal growth. Fungal susceptibility was confirmed by confocal laser scanning microscopy analysis.

RESULTS

The MICs of drugs incorporated in the materials were 0.032, 0.256, 0.128, 0.256, and 0.064 g ml(-1) for nystatin, miconazole, ketoconazole, itraconazole, and chlorhexidine, respectively. Images from nystatin, chlorhexidine, and ketoconazole demonstrated no viable cells.

CONCLUSIONS

The antimicrobials incorporated in the resilient materials inhibited fungal growth during 14 days, with lower MICs for nystatin and chlorhexidine.

Effectiveness of denture cleanser associated with microwave disinfection and brushing of complete dentures: in vivo study

Complete dentures acts as a reservoir for microbial colonization, which may lead to systemic infections. Microwave irradiation has been used as an efficient method of denture disinfection. Even though current methods eliminate denture-base microorganisms, a recurrence rate of denture stomatitis (DS) is still observed among denture-wearing patients. It was hypothesized that microwave disinfection kills microorganisms but do not remove dead bacteria from the denture surface. To test this hypothesis, the biofilm found in the dentures of 10 patients with DS was evaluated. In addition, the effects of microwave irradiation plus brushing (MW+B) on the denture biofilm and the combination of denture cleanser with microwave irradiation and brushing (MW+DC+B) for the removal of denture-accumulating microorganisms were investigated. Microbiological data were analyzed statistically by nonparametric analysis (Friedman/Wilcoxon, α=0.05). MW+B and MW+DC+B were effective in reducing the rate of microorganisms (99.2% and 99.5% respectively), but without significant difference between them (p=0.553). However, it was observed that the complete removal of microorganisms from denture surface was only possible when all regimens were combined (MW+DC+B). Microwave irradiation in combination with soaking in denture cleanser and brushing effectively disinfected the dentures and removed denture biofilm.

Update on oral fungal infections

The incidence of oral fungal infections has increased in recent years as a result of factors such as increased number of solid organ transplantations and the widespread use of immunosuppressive drug therapies. This article reviews the diagnosis and treatment of oral fungal infections. At one time oral fungal infections were a relatively uncommon event, but with advances in health care and polypharmacy in an increasingly aging population, these infections are becoming a more routine clinical finding. The dental practitioner therefore needs to be familiar with the diagnosis and management of oral fungal infections.

Susceptibility profile of a Brazilian yeast stock collection of Candida species isolated from subjects with Candida-associated denture stomatitis with or without diabetes

OBJECTIVE

This study investigated the susceptibility of 198 clinical isolates of Candida species against caspofungin, amphotericin B, itraconazole, and fluconazole.

STUDY DESIGN

Suspensions of the microorganisms were spread on Roswell Park Memorial Institute (RPMI) agar plates. Etest strips were placed on the plates, and the minimal inhibitory concentration (MIC) was read after incubation (48 h at 37 °C). Data were analyzed by a factorial analysis of variance and a 2 × 2 post hoc test (α = .05).

RESULTS

C glabrata showed the highest MIC values (P < .001) against caspofungin, itraconazole, and fluconazole. For amphotericin B, the MIC values of C tropicalis and C glabrata (P = .0521) were higher than those of C albicans (P < .001). Itraconazole was the least effective antifungal; 93.3% of the C glabrata isolates, 3.3% of the C albicans, and 1.3% of the C tropicalis were resistant. All microorganisms were susceptible to caspofungin and amphotericin B.

CONCLUSIONS

Caspofungin and amphotericin B should be recommended as an effective alternative for the management of oral Candida infections when treatment with topical or other systemic drugs has definitely failed.