Anti-biofilm effectiveness of protocols for cleaning complete dentures in hospitalized patients: a randomized controlled trial.

BACKGROUND: Denture biofilm acts as a potential reservoir for respiratory pathogens, considerably increasing the risk of lung infections, specifically aspiration pneumonia, mainly 48h after hospital admission. The establishment of a straightforward, affordable, and applicable hygiene protocol in a hospital environment for the effective control of denture biofilm can be particularly useful to prevent respiratory infections or reduce the course of established lung disease. OBJECTIVES: To evaluate the anti-biofilm effectiveness of denture cleaning protocols in hospitalized patients. METHODOLOGY: The maxillary complete dentures (MCDs) of 340 hospitalized participants were randomly cleaned once using one of the following 17 protocols (n=20): brushing with distilled water, toothpaste, or neutral liquid soap (controls); immersion in chemical solutions (1% sodium hypochlorite, alkaline peroxide, 0.12% or 2% chlorhexidine digluconate), or microwave irradiation (650 W for 3 min) combined or not with brushing. Before and after the application of the protocols, the biofilm of the intaglio surface of the MCDs was evaluated using two methods: denture biofilm coverage area (%) and microbiological quantitative cultures on blood agar and Sabouraud Dextrose Agar (CFU/mL). Data were subjected to the Wilcoxon and Kruskal-Wallis tests (α=0.05). RESULTS: All 17 protocols significantly reduced the percentage area of denture biofilm and microbial and fungal load (P<0.05). The highest percentage reductions in the area of denture biofilm were observed for 1% hypochlorite solution with or without brushing and for 2% chlorhexidine solution and microwave irradiation only in association with brushing (P<0.05). The greatest reductions in microbial and fungal load were found for the groups that used solutions of 2% chlorhexidine and 1% hypochlorite and microwave irradiation, regardless of the association with brushing (P<0.05). CONCLUSIONS: A single immersion for 10 min in 1% sodium hypochlorite, even in the absence of brushing, proved to be a straightforward, rapid, low-cost, and effective protocol for cleaning the dentures of hospitalized patients.

Effects of two novel denture cleansers on multispecies microbial biofilms, stain removal and the denture surface: an in vitro study.

BACKGROUND: The continuously increasing demand for removable denture appliances and the importance of adequate denture cleaning have led to the development of various denture cleansing products. The aim of this study was to evaluate the efficacy of two novel denture cleansing agents (GE and TM) and three commonly available cleansers (0.5% sodium hypochlorite; NaClO, 0.12% chlorhexidine gluconate; CHX, and Polident®; POL) on multispecies microbial biofilm formation, stain removal and physical properties of dentures. METHODS: The antimicrobial activities of denture cleansing agents were determined against major oral opportunistic pathogens including Streptococcus mutans, Staphylococcus aureus, Escherichia coli and Candida albicans, using time-kill assays. Multispecies microbial biofilms grown on acrylic resins for 72 h were generated to determine the antibiofilm effects of cleansing agents by confocal laser scanning microscopy (CLSM). Evaluations of the tea and coffee stain removal properties and the alterations in the physical properties of dentures were also performed. The toxicity of cleanser residues released from denture acrylics to fibroblast cells was investigated using MTT assay. RESULTS: All denture cleansing agents tested could effectively kill oral bacteria and Candida albicans. Furthermore, after immersion for more than 3 h, the cleansers Polident®, GE and TM could efficiently penetrate and inhibit multispecies denture biofilms with effects similar to 10 min of immersion in 0.5% NaClO. However, immersion in 0.12% CHX for 20 min showed less antibiofilm activity. The NaClO solution had the highest efficacy for removing stains from the artificial teeth. Conversely, the CHX solution enhanced tea and coffee staining, and the teeth immersed in this solution showed clinically unacceptable colour changes (ΔE > 5.5). However, the colour differences of teeth stained and immersed in POL, GE and TM cleansers were in the clinically acceptable range. There was no significant difference among the POL, GE and TM cleansers in terms of stain removal efficacy. The cleansers GE and TM did not alter the surface roughness and colour of the materials, moreover the residues of both cleansers did not exhibit cytotoxicity. CONCLUSION: Two novel denture cleansing agents containing natural products, GE and TM exhibited effective antimicrobial activity, antibiofilm and stain removal capabilities without toxicity or disturbance of the physical properties of acrylics.

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

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

Denture cleanser effect on resilient liners with distinct optical characteristics.

PURPOSE: To evaluate denture cleansing solutions regarding the surface roughness and color stability of two resilient liners with distinct optical characteristics used for the maximum recommended period of use. METHODS: The specimens of each resilient liner, transparent and white, were randomly distributed into groups (n= 15) of a daily 20-minute immersion simulation of 0.25%, 0.5% and 1% sodium hypochlorite (SH) and 4% acetic acid solutions. Surface roughness (Ra) and color stability (ΔE CIELab formula and NBS systems) were measured after 7, 14, 21, 30, 60, 90, 180, and 270 days. The factors of variations analyzed were material, solutions, and time of immersion. Statistical analysis used three-way ANOVA and Tukey tests (Ra), and repeated measure ANOVA (ΔE and NBS systems), P< 0.05. RESULTS: For Ra analysis, the variations occurred regardless of time and solution, as the white liner showed the greatest changes (P< 0.001). Regarding interactions between solution and time, in the period of 21 days until 270 days, Ra was equivalent for all solutions (P= 0.001). ΔE analysis showed a difference between solutions (P= 0.000) and interaction between time and solution (P= 0.000). For the transparent liner, the greatest changes were found for 1% SH after 60 days, however, at 270 days there was a color change equivalence with 0.5% SH, while 4% acetic acid solution showed intermediate values. For the white liner, 1% SH showed the highest color changes for all evaluated times, and the other evaluated solutions were similar after 270 days. For both resilient liners, 0.25% SH showed the smallest changes for the evaluated properties. CLINICAL SIGNIFICANCE: The changes found were dependent on the concentration of the solution used, as well as the length of exposure to the solution. In addition, the white resilient liner showed to be less susceptible to color changes. For both resilient liners, 0.25% sodium hypochlorite showed the least changes for the evaluated properties.

Effect of effervescent tablets on removable partial denture hygiene.

PURPOSE: To evaluate the effectiveness of five alkaline peroxide-based effervescent tablets in reducing both biofilms and the food layer adhered on the cobalt-chromium surface. METHODS: Cobalt-chromium metal alloy specimens were contaminated with Candida albicans, Candida glabrata, Streptococcus mutans and Staphylococcus aureus. After biofilm maturation, the specimens were immersed in Polident 3 Minute, Polident for Partials, Efferdent, Steradent, Corega Tabs or distilled water (control). Residual biofilm rates were determined by colony forming units counts and biofilm biomass. In parallel, to investigate the denture cleaning capability of effervescent tablets, artificially contaminated removable partial dentures were treated with each cleanser. Data were analyzed by Kruskal-Wallis followed by Dunn post hoc test or ANOVA followed by Tukey post hoc test (α= 0.05). RESULTS: None of the hygiene solutions reduced C. albicans biofilm. Efferdent and Corega Tabs promoted reduction of C. glabrata biofilm, while Steradent was favorable against S. aureus biofilm. For S. mutans, lower biofilm rates were observed after immersion in Polident for Partials and Steradent. The effervescent tablets showed good cleaning performance, removing an artificial layer with carbohydrates, proteins, and fats, however, they were not effective in removing aggregated mature biofilm. CLINICAL SIGNIFICANCE: The different effervescent tablets presented favorable antimicrobial activity against C. glabrata, S. mutans and S. aureus on cobalt-chromium surfaces and showed cleaning capability. However, for an appropriate biofilm control, a complementary method should be evaluated since none of the peroxide-based solutions reduced C. albicans biofilms or substantially removed aggregated biofilm.

Novel vinegar solution for denture-cleansing agent.

PURPOSE: To study the antimicrobial effects of a novel vinegar-based denture cleansing agent on oral Streptococci and Candida species and the inhibitory effects on pre-formed bacterial and Candida biofilms on denture base. METHODS: The microorganisms used in this study were Streptococcus mutans (S. mutans), Streptococcus sobrinus (S. sobrinus), Streptococcus sanguinis (S. sanguinis), Candida albicans (C. albicans), and Candida glabrata (C. glabrata). The antimicrobial activity of novel vinegar solution was evaluated by time kill assay and biofilm grown on denture base. RESULTS: Time kill assay showed that vinegar exhibited the highest antibacterial effect on S. sobrinus, S. sanguinis, and S. mutans after 15 min of treatment. A 99.9% reduction in C. glabrata and C. albicans required more than 4 and 6 h of treatment, respectively. Vinegar significantly inhibited streptococcal biofilm, with an approximately 6 log-reduction at 30 min of treatment. The results demonstrated that viable Candida cells in biofilm reduced in excess of 6-log CFU/mL after 3 h treatment with vinegar. Moreover, the vinegar-based denture cleanser inhibited bacterial and Candida biofilm formation compared to the control group without treatment with statistical significance. CONCLUSION: A novel vinegar-based denture cleansing agent showed moderate antibacterial properties, but required a slightly longer immersion time to attain anticandidal effects compared to Polident and 0.2% CHX.

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

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

Effect of Effervescent Denture Cleansers on 3D Surface Roughness of Conventional Heat Polymerized, Subtractively, and Additively Manufactured Denture Base Resins: An In Vitro Study.

PURPOSE: To compare the change in surface roughness of denture bases fabricated using three different techniques (additive manufacturing, subtractive manufacturing, and conventional heat-polymerizing) when immersed in two commonly available denture cleansers. MATERIALS AND METHODS: One hundred and seventeen disc-shaped denture base specimens (39/group), were fabricated by subtractive manufacturing (Wieland), additive manufacturing (NextDent Denture 3D+), and conventional heat-polymerizing (Meliodent) techniques, following the manufacturers' instructions. Specimens were randomly divided into 3 groups and immersed in two effervescent denture cleansing solutions and distilled water to simulate 180 days of denture cleansing. A 3D optical noncontact surface profilometer was used to record the surface roughness of the tested denture base materials before and after immersion. Two-way ANOVA, followed by Bonferroni post hoc test, was used to assess the effects of denture cleansers on surface roughness of tested denture base resins. RESULTS: When immersed in Fixodent and Fittydent effervescent denture cleansing solutions, the highest change in absolute surface roughness (∆Sa, in µm) was observed in additively manufactured denture base material (0.181 ±0.018 and 0.079 ±0.008), followed by heat-polymerized denture base material (0.149 ±0.012 and 0.059 ± 0.011), while subtractively manufactured denture base material showed the least change (0.110 ±0.026 and 0.038 ±0.007), respectively. There was a difference in the extent of change in surface roughness between the denture cleansers. The change in surface roughness was much higher with the Fixodent denture cleanser as compared to the Fittydent denture cleanser. CONCLUSION: Subtractively manufactured denture base resin displayed the lowest change while additively manufactured denture base resin displayed the highest change in surface roughness in both denture cleansers, but the extent of change in surface roughness was variable.

Effect of different disinfection protocols on the surface properties of CAD-CAM denture base materials.

STATEMENT OF PROBLEM: Which disinfection protocol provides optimal water contact angle and microhardness for computer-aided design and computer-aided manufacturing (CAD-CAM) polymethyl methacrylate (PMMA) materials is unclear. PURPOSE: The purpose of this in vitro study was to evaluate the effect of different disinfection protocols (1% sodium hypochlorite, denture cleanser gel, and effervescent tablet) on the water contact angle and microhardness of different CAD-CAM PMMA denture base materials by comparing them with a heat-polymerized PMMA. MATERIAL AND METHODS: Disk-shaped specimens (Ø10×2 mm) were fabricated from 3 different CAD-CAM PMMAs-AvaDent (AV), Merz M-PM (M-PM), and Polident (Poli)-and a heat-polymerized PMMA (Vynacron) (CV) (n=21). Three disinfection protocols (1% sodium hypochlorite [HC], denture cleanser gel [GEL], an effervescent tablet [TAB]) were applied to simulate 180 days of cleansing. The water contact angle and microhardness of specimens were measured before and after disinfection and compared by using a 2-way ANOVA (α=.05). RESULTS: For water contact angle, material (P=.010) and disinfection protocol (P=.002) had a significant effect. The material (P<.001), disinfection protocol (P=.001), and their interaction (P<.001) significantly affected the microhardness after disinfection. When the condition after disinfection was compared with that before disinfection, the water contact angle increased significantly in all material-disinfection protocol pairs (P≤.025), and microhardness increased significantly in all material-disinfection protocol pairs (P≤.040), except for GEL- (P=.689) or TAB-applied (P=.307) AV, HC-applied M-PM (P=.219), and TAB-applied Poli (P=.159). CONCLUSIONS: The material and disinfection protocol affected the water contact angle of all tested PMMAs after disinfection, resulting in more hydrophobic surfaces for heat-polymerized or CAD-CAM PMMAs. The microhardness of heat-polymerized PMMA was less than that of all CAD-CAM PMMAs after disinfection, regardless of the protocol.

Influence of Three Different Denture Cleansers on Surface Roughness and Strength of Heat-polymerizing Resin: An In Vitro Study.

AIM: The purpose of the current study was to evaluate the impact of three different denture cleansers on the strength and surface roughness of heat-polymerizing resin. MATERIALS AND METHODS: A total of 120 resin discs (10 mm in diameter and 2 mm thick) were created using a stainless steel mold for surface roughness testing and flexural strength testing (in accordance with the American Dental Association (ADA) Specification No.12). Samples were divided into one of three groups (40 samples in each group): group I: Clanden, group II: Clinsodent, group III: Fittydent. Samples were immersed in denture-cleansing solutions for 30 minutes every day, and this process was repeated over a period of 15 days. Samples were stored in distilled water at room temperature in between the immersions. A surface analyzer was utilized to compare the surface roughness of each sample before and after immersion treatments. For recording flexural strength, each sample was subjected to three-point bending test by mounting samples on Universal testing machine. Comparing mean values between groups using one-way ANOVA and the Tukeys honest significant difference (HSD) post hoc test. A significance level of 0.05 was used for all statistical calculations Results: After 15 days, the maximum change of mean surface roughness of heat-polymerizing resin was found in Clanden denture cleanser group (2.64 ± 0.12) followed by Clinsodent group (2.26 ± 0.09) and Fittydent group (1.92 ± 0.06). After 15 days, the maximum change of mean flexural strength changes of heat-polymerizing resin was found in Clanden denture cleanser group (94.78 ± 0.14), followed by Fittydent group (98.64 ± 0.03) and Clinsodent group (99.26 ± 0.21). CONCLUSION: Within the limitation, the current study concluded that changes were observed in surface roughness and flexural strength of all heat-polymerizing resin samples after immersion in all three denture cleansers; but least surface roughness and flexural strength changes were observed with the Fittydent cleanser group and Clinsodent group, respectively. CLINICAL SIGNIFICANCE: Cleaning dentures is crucial for maintaining both the prosthesis and oral health; therefore, it is necessary to select a cleanser that is effective without negatively affecting the base resin's qualities over time.

Effects of Denture Cleaning Regimens on the Quantity of Candida on Dentures: A Cross-Sectional Survey on Nursing Home Residents.

Oral care involving a denture cleaning regimen is important for reducing the incidence of systemic diseases. However, limited information is currently available on denture cleaning frequencies and regimens. Therefore, the present study investigated the relationship between the number of Candida spp. present on the complete dentures of nursing home residents and cleaning regimens. Residents were surveyed to assess their denture cleaning methods. Plaque was collected by applying a sterile swab to the mucosal surface of each examined complete denture worn by 77 residents, and the Candida spp. collected were cultured, identified, and quantified. The relationship between denture cleaning regimens and the quantity of Candida spp. was investigated. Correlation and multivariable analyses revealed that the strongest factor influencing the number of Candida spp. on dentures was the frequency of use of denture cleansers. The number of Candida spp. was the lowest on dentures cleaned daily with a denture cleanser. The present results demonstrated that the daily use of a denture cleanser effectively controlled the adherence of Candida spp. to dentures. Oral and other healthcare providers need to provide instructions on and assist nursing home residents with the daily care of dentures, using denture cleansers, including the environment where cleaning is performed.

Influence of brushing with antiseptic soap solution on the surface and biological properties of an acrylic denture base resin.

PURPOSE: To evaluate the influence of brushing with specific antiseptic soap solution on the surface (roughness, hardness, and color stability) and biological properties of a specific heat-polymerized denture base resin. METHODS: 189 denture base acrylic resin specimens (10 mm x 1.2 mm) were made and distributed into three groups: sodium hypochlorite 0.5% (SH), Lifebuoy solution 0.78% (LS) and phosphate-buffered saline (PBS) and were submitted to the brushing cycle for 10 seconds. For each property assessed the sample size was composed of nine specimens. Roughness, hardness, and color stability were assessed before and after the cycle. For the biological properties (biofilm formation and reduction capacity) the colony forming unit and Alamar Blue assays were performed. For this, the specimens were placed separately in a 24-well plate with medium containing C. albicans. The plate was incubated for 48 hours for the formation of mature biofilm. The data were submitted to two-factor ANOVA (roughness and hardness) and one-way ANOVA (color stability and biological properties) and Tukey's post-test (α= 0.05). RESULTS: The Lifebuoy group did not present a statistical difference (P> 0.05) in relation to the other groups for the evaluated surface properties (roughness, hardness, and color stability). Also, from the colony-formation unit and Alamar Blue assays, there was no statistical difference (P> 0.05) between the groups. Regarding biofilm reduction capacity formed on the samples, the results obtained from the count of colony forming units (CFU/mL) showed a reduction of approximately 1.3 logs in the number of CFU/mL in the Lifebuoy group (µ = 4.78 log¹º) compared to the negative control group (µ = 6.02 log¹º) (P< 0.05). When evaluating the cellular metabolism of C. albicans cells, the experimental group did not show any statistical difference compared to controls (P> 0.05). Brushing with Lifebuoy soap solution did not alter the surface properties of the acrylic resin, and reduced the C. albicans biofilm. CLINICAL SIGNIFICANCE: Brushing removable partial or total dentures can be performed using Lifebuoy liquid disinfectant soap, as a simple, low-cost, and effective method for removing biofilm.

Effects of long-term cinnamaldehyde immersion on the surface roughness and color of heat-polymerized denture base resin.

STATEMENT OF PROBLEM: Cinnamaldehyde has been successfully used for the short-term disinfection of dentures; however, its long-term effects on the surface and color properties of denture base materials remain unknown. PURPOSE: The purpose of this in vitro study was to evaluate the effects of simulated immersion in cinnamaldehyde for up to 5 years on the surface roughness and color parameters of a heat-polymerized denture resin. MATERIAL AND METHODS: Eighty Ø10×5-mm disk-shaped specimens were prepared from microwave heat-polymerized polymethylmethacrylate (PMMA) and immersed in 4 solutions (n=20): TW-tap water (control), SH - 0.5% sodium hypochlorite, PX-alkaline peroxide, and CA-cinnamaldehyde (27 µg/mL). The immersion protocol simulated 104 cycles (3.5 months), 913 cycles (2.5 years), and 1825 immersion cycles (5 years) of a daily immersion cleaning protocol, with immersion times ranging from 10 to 20-minutes. Surface roughness (Sa) and the color parameters of CIELab (L∗ a∗ b∗, ΔEab), CIEDE2000 (ΔE00), and the National Bureau of Standards (NBS) were analyzed at baseline (t=0) and after the immersion cycles. The data were analyzed by 2-way analysis of variance (ANOVA) for repeated measures and the Tukey post hoc test (α=.01). RESULTS: Sa was significantly increased in all groups after 1825 cycles compared with baseline (P<.01), regardless of the solution. Only the time factor significantly affected ΔEab, ΔE00, and NBS parameters, which were below the perceptibility and acceptability thresholds. After a simulated 5-year immersion, the surface roughness and color values of CA-treated specimens were not statistically different from those of the other groups (P>.01). CONCLUSIONS: Cinnamaldehyde solution (27 µg/mL) produced minor effects on the surface roughness and color parameters of a heat-polymerized denture base resin similar to those of 0.5% sodium hypochlorite and alkaline peroxide after a 5-year simulated immersion.

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.

Anticandidal efficacy on polymide based denture resin using Photodynamic therapy, chemical and herbal disinfectants and their effect on surface roughness and hardness.

AIM: The present study aimed to evaluate the anticandidal effectiveness of PDT, DL, Triphala, CHX, and NE and their effects on Ra and the hardness of polyamide denture base colonized with C. Albicans. MATERIAL AND METHODS: A total of 50 thermo-injected polyamide denture resins were constructed and inoculated by the American Type Culture Collection (ATCC) of C. albicans in an in-vitro setup. The specimens were arbitrarily allocated into five groups, pre-candida count was measured then subjected to the diverse polyamide denture disinfection methodologies: Group 1: PDT, Group 2: Diode Laser, group 3: Triphala, group 4: 0.12% CHX (Control) and group 5 Neem extract. After disinfection protocol, post-candida count (CFU/ml) was assessed. Surface roughness and surface hardness of polyamide dentures were evaluated and statistical differences in the Ra and Vickers hardness was also assessed. Statistical analysis was performed for CFU/mL (log10) for exposed C. albicans by two-way ANOVA and Tukey's multiple test (p>0.05). For normality of the data, Kolmogorov Smirnov test was executed. RESULTS: The highest anti-microbial efficacy against Candida colonies was displayed by chemical control group 0.12% CHX (11.39 ± 1.8 CFU/ml). This was comparable to herbal NE (12.45 ± 2.9 CFU/ml) (p>0.05). There was no statistical difference found in the surface hardness values among the disinfected groups. Group 2: DL (1.32 ± 0.13 µm) showed the highest Ra value comparable to group 1: PDT (1.21 ± 0.22 µm) CONCLUSION: Polyamide denture base colonized with C. Albicans and disinfected with 0.12% Chlorhexidine and Neem extract demonstrated the highest antimicrobial efficacy with decreased surface roughness and no alteration in denture hardness.

Evaluation of the time-dependent efficacy of commercial denture or orthodontic appliance cleansers: An in vitro study.

The aim of this study was to evaluate the antimicrobial, stain and protein removal efficacy of denture or orthodontic appliance cleansers using in vitro test methods. Experimental cleansers were applied for experimental time in each evaluation method. To evaluate the microorganism removal efficacy, C. albicans and S. mutans removal rate was calculated from the specimen surface. Stain and protein removal rate was calculated using the spectrophotometer. Experimental cleansers significantly affected the microorganism removal rate for both C. albicans and S. mutans, as well as the stain and protein removal rates, at each experimental time (p<0.05). As the application time increased, the stain and protein removal rates of all experimental cleansers significantly increased (p<0.05). The present study provided in vitro evaluation methods to assess the efficacy of denture or orthodontic appliance cleansers. Also, manufacturers and researchers can predict clinical outcomes and ensure proper hygiene management of dentures or orthodontic appliances.

Effect of local hygiene protocols on denture-related stomatitis, biofilm, microbial load, and odor: A randomized controlled trial.

STATEMENT OF PROBLEM: Denture stomatitis affects complete denture wearers and is frequently treated with antifungals drugs, as well as treating the denture with sodium hypochlorite. Whether the limitations of these treatments can be overcome with local hygiene protocols that do not damage the denture materials or adversely affect the patient is unclear. PURPOSE: The purpose of this randomized controlled trial was to evaluate the effect of denture hygiene protocols on complete denture wearers with denture stomatitis. MATERIAL AND METHODS: For this randomized, double-blind controlled clinical trial, 108 participants were assigned to parallel groups: 0.25% sodium hypochlorite (positive control) 0.15% Triclosan, denture cleaning tablets, or denture cleaning tablets plus gingival cleaning tablets. The participants were instructed to brush the dentures and the palate and immerse the denture in the solutions. The outcomes of denture stomatitis remission, biofilm removal, decrease of microbial load (colony-forming units), and odor level of the mouth and denture were measured at baseline and after 10 days. Descriptive analyses were used for sociodemographic characterization of the participants; the Pearson chi-square test was used to compare participant frequency with different degrees of denture stomatitis. The data were not normally distributed (Shapiro-Wilks test) or homogeneous (Levene test). So, the Kruskal-Wallis and Dunn post hoc tests and Wilcoxon test were used to compare the effects of solutions and time on the variables (α=.05). RESULTS: The frequency of the highest to lowest denture stomatitis scores was significantly different for the 0.15% Triclosan and denture cleaning tablets groups. No significant difference was found among the groups in terms of denture stomatitis scores, biofilm, or colony-forming unit count of Candida spp. or C. albicans and S. mutans; a significant reduction was found in these parameters. The 0.25% sodium hypochlorite and 0.15% Triclosan treatments caused a significant reduction in Gram-negative microorganisms; these 2 protocols, and the denture cleaning tablets showed a significant reduction in Staphylococcus spp.; all protocols had similar effects. Only the S. mutans count of the palate decreased after 10 days. The odor level of the mouth and the denture was not significantly different (P=.778). CONCLUSIONS: The evaluated protocols can be recommended for the hygiene of complete dentures, since they were effective for all the variables studied.

Complete denture hygiene solutions: antibiofilm activity and effects on physical and mechanical properties of acrylic resin.

BACKGROUND: Appropriated denture hygiene is a predictive factor for longevity of rehabilitation treatment and maintenance of the oral mucosal health. Although, disinfectant solutions are commonly used as denture cleansers, the impact of these solutions on acrylic resin-based dentures remain unclear. OBJECTIVE: To evaluate, in vitro, the antibiofilm activity of complete denture hygiene solutions and their effects on physical and mechanical properties of acrylic resin. METHODOLOGY: For antibiofilm activity measurement acrylic resin specimens were contaminated with Candida albicans, Candida glabrata and Streptococcus mutans. After biofilm growth, the specimens were assigned to the hygiene solutions: Distilled water (Control); 0.2% Sodium hypochlorite (SH); Efferdent Power Clean Crystals (EPC) and 6.25% Ricinus communis (RC). The viability of microorganisms was evaluated by agar plate counts. In parallel, physical, and mechanical properties of the acrylic resin were evaluated after simulating a 5-year period of daily immersion in the previously mentioned solutions. The changes in surface roughness, color, microhardness, flexural strength, impact strength, sorption and solubility were evaluated. Data were compared by ANOVA followed by the Tukey test or Kruskal-Wallis followed by the Dunn test depending on the distribution (α=0.05). RESULTS: Regarding antibiofilm action, SH eliminated all microorganisms while EPC and RC exhibited moderate action against S. mutans (p=0.001) and C. glabrata (p<0.001), respectively. Relative to effects on the physical and mechanical properties of the acrylic resin, RC led to higher values of color change (p=0.030), hardness (p<0.001), surface roughness (p=0.006) and flexural strength (p<0.001). Moreover, RC induced the highest values of changes in solubility (p<0.001). EPC promoted greater changes in surface morphology, whereas immersion in SH retained the initial appearance of the acrylic resin surface. All hygiene solutions reduced the impact strength (p<0.05). CONCLUSION: SH presented the most effective antibiofilm activity. In addition, changes on properties were observed after immersion in RC, which were considered within acceptable limits.

Development of a novel denture care agent with highly active enzyme, arazyme.

BACKGROUND: The importance of efficient denture deposit removal and oral hygiene has been further underscored by the continuous increase of denture wearers. Denture hygiene management has also become an important aspect associated with denture-induced stomatitis. This study aims to evaluate the denture cleaning effect of arazyme, the metalloprotease produced from the Serratia proteamaculans HY-3. We performed growth inhibition tests against oral opportunistic pathogens to be used as a potential oral health care agent. METHODS: The proteolytic activities of arazyme was evaluated over broad ranges of temperature, pH, and denture components compared to those of subtilisin in commercially available denture cleansers. The washing effects of arazyme were also measured by using homogeneously soiled EMPA 105 cottons. To investigate the denture cleaning capability of arazyme, artificially contaminated dentures were treated with arazyme, subtilisin (Everlase 6.0T), and Polident®, respectively. The growth kinetics of Candida albicans, Enterococcus faecalis, Staphylococcus epidermis, and Streptococcus mutans were evaluated in the presence of different concentrations of arazyme to estimate the prevention effects of arazyme against major oral opportunistic pathogens. RESULTS: Arazyme showed strong proteolytic activities over wide temperature and pH ranges compared with the serine protease of the subtilisin family. Arazyme demonstrated efficient removal and decomposition of artificially contaminated dentures and showed explicit washing effects against soiled cottons. Moreover arazyme inhibited the growth of oral opportunistic pathogens, including C. albicans, E. faecalis, S. epidermis, and S. mutans, with more than 80% inhibition against C. albicans, the major cause of denture stomatitis, with 250 mg/mL arazyme. CONCLUSIONS: Arazyme shows promise as a biological oral health care agent with effective cleaning and antimicrobial activities and is a potential source for developing novel denture care agents.