An In Vitro Evaluation of Denture Cleansing Regimens against a Polymicrobial Denture Biofilm Model

Denture stomatitis (DS) is an inflammatory disease resulting from a polymicrobial biofilm perturbation at the denture surface–palatal mucosa interface. Recommendations made by dental health care professionals often lack clarity for appropriate denture cleaning. This study investigated the efficacy of brushing with off-the-shelf denture cleanser (DC) tablets (Poligrip®) vs. two toothpastes (Colgate® and Crest®) in alleviating the viable microorganisms (bacteria and fungi) in an in vitro denture biofilm model. Biofilms were grown on poly(methyl)methacrylate (PMMA) discs, then treated daily for 7 days with mechanical disruption (brushing), plus Poligrip® DC, Colgate® or Crest® toothpastes. Weekly treatment with Poligrip® DC on day 7 only was compared to daily modalities. All treatment parameters were processed to determine viable colony forming units for bacteria and fungi using the Miles and Misra technique, and imaged by confocal laser scanning microscopy (CLSM). Brushing with daily DC therapy was the most effective treatment in reducing the viable biofilm over 7 days of treatment. Brushing only was ineffective in controlling the viable bioburden, which was confirmed by CLSM imaging. This data indicates that regular cleansing of PMMA with DC was best for polymicrobial biofilms.

Intra Oral Mucosal Conditions in Older Patients With and Without Complete Dentures: A Cross-sectional Study.

Objectives: To obtain baseline information on Oral Mucosal Conditions (OMCs) and its relation to age, sex, medical history and the use of complete denture in a sample of edentulous patients. Materials and methods: Edentulous patients attending a university hospital were examined for the presence of OMCs, and demographic data were recorded. Statistical analysis was carried out on SPSS software; the following statistical tests were utilized: descriptive statistics, The Mann Whitney U test, Spearman’s Rho rank correlations, and The hierarchical logistic regression analysis. Results: A total of one hundred and sixty-one participants were examined (34 females and 127 males with a mean age of 59.08 years). More than half of the participants (59.6 %) were non-denture wearers and (40.6%) were denture wearers. Longer edentulism, using dentures for longer duration, and the use of more previous dentures were associated with higher Atwood’s ridge classification. Smoking was associated with higher prevalence of OMCs, particularly hairy tongue, frictional keratosis, smokers’ palate, and leukoedema. Denture wearers had more denture stomatitis and denture induced hyperplasia, and less frictional keratosis than non-denture wearers. Participants with cardiac disease had more incidences of geographic tongue and tie tongue. Conclusion: Mucosal changes with increased age, smoking, medical conditions, and medications may be superimposed by wearing complete dentures.

Denture Acrylic Resin Material with Antibacterial and Protein-Repelling Properties for the Prevention of Denture Stomatitis

Denture stomatitis is a multifactorial pathological condition of the oral mucosa that affects up to 72% of denture wearers. It is commonly seen on the palatal mucosa and characterized by erythema on the oral mucosa that are in contact with the denture surface. The aim of this study was to incorporate 2-methacryloyloxyethyl phosphorylcholine (MPC) and dimethylaminohexadecyl methacrylate (DMAHDM) into a high impact polymethylmethacrylate heat-cured denture base acrylic resin as a potential treatment for denture stomatitis. We used a comparative study design to examine the effect of incorporating MPC as a protein repellent agent and DMAHDM as an antifungal agent to prevent the adherence of Candida albicans to the denture base material. The dual incorporation of MPC and DMAHDM reduced C. albicans biofilm colony-forming unit by two orders of magnitude when compared to the control group devoid of the bioactive agents. Although the addition of MPC and DMAHDM alone or in combination significantly reduced the flexural strength of the material, they showed reduced roughness values when compared to control groups. This new denture acrylic resin provides the benefit of enhancing C. albicans biofilm elimination through dual mechanisms of action, which could potentially reduce the prevalence of denture stomatitis.

Epidemiology, etiology, and treatment of denture stomatitis

Multiple factors are involved in the pathogenesis of denture stomatitis, which increases the risk of tissue infection and inflammation. These factors include poor oral hygiene, trauma secondary to poorly fitting prostheses, resin porosity, and bacterial plaque accumulation. Our present review discusses the epidemiology, etiology, and treatment of denture stomatitis based on data from current studies in the literature. The prevalence of denture stomatitis is significantly variable among the different studies, as previously discussed. However, the cumulative incidence of denture stomatitis among their participants ranged between 17-77%. These hugely variable rates have been attributed to the nature of data collection, diagnostic criteria, sample size, and patient demographics. Studies also show that the condition is more prevalent among elderly females. However, not many studies have reported this correlation, indicating the need for future studies. Candida albicans infection is the primary parameter in the etiology and pathogenesis of the condition. However, other factors related to the patient (like status of immunological response) and dentures (like hygiene) were also reported. Therefore, the management of denture stomatitis should be based on applying adequate interventions. Besides, using antifungal medications is also necessary to eradicate organism.

Development and Evaluation of Clove and Cinnamon Supercritical Fluid Extracts-Loaded Emulgel for Antifungal Activity in Denture Stomatitis

Denture stomatitis (DS), usually caused by Candida infection, is one of the common denture-related complications in patients wearing dentures. Clove and cinnamon oils have been acknowledged for their anti-inflammatory, antimicrobial activity, and antifungal effects in the oral cavity. The aim of this study, therefore, was to prepare clove/cinnamon oils-loaded emulgel and to assess its efficacy in treating Candida albicans-associated denture stomatitis. Central composite design was adopted to formulate and optimize clove/cinnamon extracts-loaded emulgel. The formulated preparations were assessed for their physical appearance, particle size, viscosity, spreadability, and in-vitro drug release. In addition, in-vivo therapeutic experiments were conducted on 42 patients with denture stomatitis. The prepared emulgel formulations showed good physical characteristics with efficient drug release within 3 h. In addition, in-vivo antifungal studies revealed that the optimized formula significantly (p < 0.001) reduced Candida colony counts from the denture surface, compared to commercially available gel (240.38 ± 27.20 vs. 398.19 ± 66.73 CFU/mL, respectively). Furthermore, the optimized formula and succeeded in alleviating denture stomatitis-related inflammation with a better clinical cure rate compared to commercially available gel Collectively, herbal extracts-loaded emulgel might be considered an evolution of polyherbal formulations and might represent a promising alternative to the existing allopathic drugs for the treatment of denture stomatitis, with better taste acceptability and no side effects.

The Effectivity of Parsley (Petroselinum crispum) Extract on The Growth Inhibition of Candida Albicans

Background: Denture stomatitis is a type of Candida-associated infection that mainly affects the palatal mucosa. Candida albicans is one of the normal flora that is considered to be the primary etiologic agent in the pathogenesis of denture stomatitis. Denture decontamination is necessary to prevent denture stomatitis. One method of decontamination is by immersing removable dentures in an antifungal solution. Parsley (Petroselinum crispum) is a medicinal plant showing antifungal activity. Objectives: To determine the effectivity of immersion of acrylic resin Plate in parsley extract on inhibition of growth of Candida albicans. Methods: The effectivity of immersion of heat-cured acrylic resin plates in parsley extract on inhibition of C. albicans growth was tested using an experimental laboratory study with a post-test-only control group design. Thirty samples were divided into 5 groups as 0.01%, 0.02%, and 0.05% parsley ethanol extract, 0.1% sodium hypochlorite, and sterile aquadest. The number of colony forming units per mL was obtained after calculating the colonies on SDA media, allowing the minimum inhibitory concentration (MIC) obtained according to the formula. Results: 0.01% parsley ethanol extract is MIC with a mean of 7.4 CFU / ml, which inhibited the growth of C. albicans by 31.05%. The Kruskal Wallis test (p<0.001) results indicate that there is an effectivity of immersion of acrylic resin plate in parsley extract on inhibition of growth of C. albicans. Conclusions: The immersion of acrylic resin plates in parsley ethanol extract with a concentration of 0.01%, 0.02%, and 0.04% has effectivity on the inhibition of growth of C. albicans.

DIFFERENCES IN THE NUMBER OF CANDIDA ALBICANS COLONIES ON ACRYLIC RESIN AND THERMOPLASTIC NYLON IN SOURSOP LEAF EXTRACT IMMERSION

Introduction: Denture stomatitis is a chronic inflammation caused by wearing dentures, mainly caused by Candida albicans. Heat-polymerized acrylic resins are often used as denture bases, but lack the ability to absorb liquids due to their porosity and surface roughness. The basis of the latest dentures is thermoplastic nylon because it is more aesthetically, hypoallergenic and more flexible. Soursop leaf extract contains alkaloids, tannins, flavonoids, and saponins as antifungal. The purpose of this study was to examinate whether there were differences in the number of Candida albicans colonies on heat-polymerized acrylic resin plates and thermoplastic nylon in soursop leaf extract immersion. Materials and Methods: The research design was an experimental pre-post test with control group design, n = 50 plates were divided into 2 groups, heat-polymerized acrylic resin (n=25) and thermoplastic nylon (n=25), divided into 5 groups, 3 treatment groups using 10%,15%,25% soursop leaf extract, Fittident®and aquadest in the control groups. Samples were contaminated with Candida albicans suspension and incubated, counted before immersion for 8 hours, then put in Saboroud’s bath and counted again. Results and Discussions: Wilcoxon test analysis showed significant differences in all groups, except the aquadest group. The Mann-Whitney test showed significant differences between the treatment groups, except between the 25% extract and the Fittident®control group. Also, showed a significant difference in the 15% concentration group between heat-polymerized acrylic resin and thermoplastic nylon. Conclusion:There was a difference in the decrease in the number of Candida albicans colonies on heat-polymerized acrylic resin plates and thermoplastic nylon in soursop leaf extract at a concentration of 15%, while at concentrations of 10% and 25% there was no difference

Preliminary study into the effects of tobacco smoke on Candida albicans

Background: Denture-stomatitis (DS) is the most common form of oral candidosis with increased prevalence in cigarette smokers (Akram et al. 2018). Interestingly, tobacco condensate (TC) increases Candida albicans adhesion, growth, biofilm-formation, virulence gene expression (Semlali et al. 2014)and hyphal production (Awad and Karuppayil 2018). We hypothesised that TC-treated denture acrylic would therefore affect C. albicans within acrylic biofilms. Methods: Acrylic discs (pre-conditioned with TC, artificial saliva (AS) or water) were incubated at 37°C with C. albicans (n=6) for 90 min or 24 h. Adherent Candida were stained with calcofluor white and confocal laser scanning microscopy (CLSM) used to assess levels of adherence, biofilm and hyphal numbers. Expressed virulence genes (n=7) were measured by qPCR. Results: CLSM showed that effects of TC-treatment were strain dependent. Adherence of C. albicans PTR/94 to TC-treated surfaces was significantly (P<0.002) lower than on the untreated control. Biofilm levels of PTR/94 after 24 h were found to be significantly higher on AS-treated acrylic than the TC-treated and untreated control. Five strains had significantly fewer filamentous forms after 90 min on TC-treated surfaces. TC-treatment promoted hyphal levels for strain 705/93 after 24h. Conclusion: TC pre-conditioning altered adherence and biofilm coverage of C. albicans to acrylic surfaces and influenced hyphal development. Work is ongoing to ascertain the significance of these effects on C. albicans pathogenicity. Akram et al. (2018). Journal of Oral Science 60(1):115–120. Awad and Karuppayil (2018). American Journal of Clinical Microbiology and Antimicrobials1(3):1–6. Semlali et al. (2014). BMC Microbiology. 14:61

Recovery of Candida spp. from a denture rat model

Denture stomatitis is a common infection in denture wearers. This study evaluated the recovery of Candida spp. from the palate of Wistar rats after using an acrylic device with single and mixed-species of Candida spp. After approval of the Ethics Committee, 84 male and female Wistar rats were used. Custom-made acrylic devices were fabricated for each animal and sterilized by microwave irradiation. Single and mixed species biofilms of C. albicans (Ca), C. glabrata (Cg), and C. tropicalis (Ct) were grown on the devices for 48 h at 37°C. Rats were anesthetized and the devices were cemented on the molar teeth (n=5 for each sex and Candida spp.). Rats received a carbohydrate-rich diet. Single and mixed species were inoculated in the oral cavity thrice after three-day intervals. Controls received only dentures without Candida spp. After 4 weeks, the devices were removed, the palates were swabbed, and diluted samples were plated on Agar Sabouraud Dextrose and CHROMAgar Candida for colony counting and presumptive identification, respectively, after 48 h. Data were analyzed by 3way ANOVA (α=5%). There was a significant interaction (p=0.003) between sex and species. For females, all groups recovered significant values (p≤0.027) compared with controls. For males, groups with Ct as single and dual-species showed the lowest values without difference (p≥0.183) with the control. The groups with triple-species showed the highest values but without difference (p≥0.071) with the groups with single and dual-species, except males with Ct. Ct alone showed reduced recovery from palate of male rats.