Fungicidal and inhibitory efficacy of cinnamon and lemongrass essential oils on Candida albicans biofilm established on acrylic resin: An in vitro study

Statement of problemIt is unclear whether cinnamon and lemongrass essential oils can effectively reduce the Candida-biofilm frequently formed on dental devices made from heat-polymerized polymethyl methacrylate (PMMA) resin that contributes to the development of mild oropharyngeal as well as life-threatening candidiasis in patients wearing the devices.PurposeThe purpose of this in vitro study was to determine the efficacy of cinnamon and lemongrass essential oils in eradicating Candida albicans biofilm on heat-polymerized PMMA specimens and to determine whether they retard the formation of fungal biofilm.Material and methodsThe antifungal effect of cinnamon and lemongrass essential oils was determined by using agar disk diffusion and broth microdilution methods to obtain minimum inhibitory concentrations. The mature C albicans biofilm (48 hours) was pre-established on PMMA specimens before being individually treated with various concentrations (½, 1, 2, 4, 8, 16 times minimum inhibitory concentration) of each tested oil for different exposure times (1, 2, 4, 8, and 24 hours). In another experiment, fungal biofilm was established on the PMMA specimens that were primed individually with various concentrations of the tested oils for different times. The 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT)-reduction assay was used to quantitate biofilm viability in both experiments. Statistical analysis was performed by using the 1-sample Kolmogorov-Smirnov test and 2-way ANOVA followed by the Tukey multiple comparison test (α=.05).ResultsMinimum inhibitory concentration values of cinnamon and lemongrass essential oils against planktonic C albicans were 0.1 μL/mL (0.01% v/v) and 0.4 μL/mL (0.04% v/v). At 8 times the minimum inhibitory concentration, cinnamon oil (0.8 μL/mL or 0.08% v/v) and lemongrass oil (3.2 μL/mL or 0.32% v/v) eradicated the pre-established fungal biofilm by 99.0% in an exposure time of 1 hour. In contrast, high concentrations of 8 and 16 times the minimum inhibitory concentration of cinnamon oil (0.8 μL/mL or 0.08% v/v) and lemongrass oil (6.4 μL/mL or 0.64% v/v) coated on PMMA specimens for 24 hours were only able to inhibit the formation of fungal biofilm by approximately 70.0%.ConclusionsCinnamon and lemongrass essential oils can eliminate pre-established C albicans biofilm and restrain the formation of fungal biofilm on heat-polymerized PMMA specimens. Both effects of the tested essential oils depended on dose and exposure or priming time.     

Functional outcome of two different grafting techniques in the surgical management of oral submucous fibrosis: a comparative evaluation

Objective

To evaluate the functional efficacy of two different grafting techniques following the fibrotomy among subjects with oral submucous fibrosis (OSMF).

Design

Forty consecutively treated OSMF subjects between 20 and 40 years who had grades 3 and 4a OSMF and mouth opening?<?15 mm were included in the present study. All the subjects were randomly divided into two groups. In Group I, all the subjects received a buccal pad of fat sandwiched with a nasolabial flap following fibrotomy. In contrast, Group II subjects received a buccal pad of fat combined with a collagen graft. The effect of two different surgical protocols on mouth opening was evaluated clinically before the surgery (T₀) and 1 month (T₁), 6 months (T₂), and 12 months (T₃) after the surgery.

Results

In Group I subjects, the mouth opening increased significantly (P?<?0.001) from 10.90?±?1.971 mm at T₀ to 34.25?±?3.127 mm at T₁, but reduced marginally to 32.15?±?3.422 mm at T₂, and 31.30?±?3.358 mm at T₃. In Group II, the mouth opening increased significantly (P?<?0.001) from 10.85?±?1.725 mm at T₀ to 28.90?±?3.059 mm, 29.10?±?2.808 mm, and 28.20?±?2.285 mm at T₁, T₂, and T_3, respectively. At the end of 12 months of follow-up, the mean value improvement in the mouth opening (T₀–T₃) was 20.4?±?3.5 mm and 17.3?±?2.9 mm in Groups I and II, respectively, and the difference was statistically significant (P?=?0.006).

Conclusion

The buccal pad of fat sandwiched with a nasolabial flap for the reconstruction following fibrotomy had a slightly better beneficial effect on the postoperative mouth opening among OSMF subjects.

     

Inhibitory effect of alpha-mangostin on <Emphasis Type="Italic">Candida</Emphasis> biofilms

The objective of this study was to determine the inhibitory effect of alpha-mangostin on Candida biofilms. Candida species including Candida albicans, Candida krusei, Candida tropicalis, and Candida glabrata were tested. Candida biofilms were formed in flat-bottomed 96-well microtiter plates. The metabolic activity of cells within biofilms was quantified using the XTT assay. The results demonstrated that alpha-mangostin showed a significant anti-biofilm effect on both developing biofilms and preformed biofilms of Candida species. It may be concluded that alpha-mangostin could be an anti-biofilm agent against Candida species. Further in vivo investigations are needed to uncover the therapeutic values of this medicinal plant.     

Synergistic activity of lysozyme and antifungal agents against Candida albicans biofilms on denture acrylic surfaces

Denture related oral candidiasis is a recalcitrant fungal infection not easily resolved by topical antifungals. The antimycotic protein lysozyme, in saliva is an important host defense mechanism although its activity against Candida biofilms on denture acrylic has not been evaluated.

Objectives

(i) To establish a clinically relevant denture acrylic assay model to develop standardized Candida albicans biofilms, and (ii) assess the inhibitory effects of lysozyme alone and, the latter combined with antifungals (nystatin, amphotericin B, ketoconazole and 5-fluorocytosine) on sessile Candida cells and, finally (iii) to visualize the accompanying ultrastructural changes.

Design

The rotating-disc biofilm reactor was used to develop standardized 48 h Candida biofilms on acrylic discs in YNB/100 mM glucose medium and the biofilm metabolic activity was monitored using a tetrazolium reduction assay.

Results

The biofilm metabolic activity was similar in 18 identical denture acrylic discs (p < 0.05) thus validating the rotating-disc biofilm model. Very low concentrations of lysozyme (6.25 μg/ml) significantly (p < 0.01) inhibited Candida biofilm formation indicating that lysozyme may likely regulate intra-oral Candida biofilm development. Although 100 μg/ml lysozyme killed 45% of sessile Candida cells, further increasing its concentration (up to 240 μg/ml) had no such effect. Nystatin, amphotericin B, and ketoconazole in association with 100 μg/ml lysozyme exhibited effective synergistic killing of biofilm Candida in comparison to drug-free controls. Scanning electron and confocal scanning laser microscopy analysis confirmed the latter trends.

Conclusion

Our results indicate that agents found in biological fluids such as lysozyme could be a safe adjunct to antifungals in future treatment strategies for recalcitrant candidal infections.     

Efficacy of resin-modified glass ionomer cement varnish in the prevention of white spot lesions during comprehensive orthodontic treatment: a split-mouth study

Abstract

Objective:

To evaluate the efficacy of resin-modified glass ionomer cement varnish in the prevention of white spot lesions (WSLs) during early orthodontic treatment with fixed appliances.

Materials and methods:

A total of 480 maxillary and mandibular anterior teeth were studied. The varnish was applied to either the right or left side of the maxillary or mandibular anterior teeth on a random basis. For each experimental quadrant in each patient, the varnish was applied to the labial surfaces of incisors and canines, from the gingival surface of the bracket to the free gingival margin. White spot lesions were recorded on a standard pro forma before (T ₀) and approximately 6?months following varnish application (T ₁) by DIAGNOdent and direct visual inspection.

Results:

The DIAGNOdent score at T ₁ was increased significantly in the control maxillary lateral and mandibular central (P?<?0·05), and lateral incisors (P?<?0·01). The visual scores in experimental maxillary lateral incisors and mandibular canines were decreased significantly at T ₁ (P?<?0·05). The sidewise post-treatment (T ₁) comparisons of control and experimental teeth for visual scores revealed significant decreases for maxillary lateral incisors, maxillary canines and mandibular canines (P?<?0·05).

Conclusion:

Application of resin-modified glass ionomer cement varnish had a favourable effect in the prevention of WSLs during comprehensive orthodontic treatment.     

Ultrasound dimensional changes of the anterior belly of the digastric muscle induced by orthognathic surgery and botulinum toxin A injection in Class II malocclusion

Objectives

The aim of the study is to evaluate the ultrasonographic dimensional changes of the anterior belly of the digastric muscle (ABDM), occurring after intramuscular botulinum toxin A (BTX-A) injection during orthognathic surgery, in a series of five Class II malocclusion patients.

Methods

All the patients received 20 units of BTX-A, into both ABDM, intraoperatively. The length, width and cross-sectional area (CSA) of the ABDM were ultrasonographically measured at three different time points: T₀ (preoperatively), T₁ (postoperatively at 2 weeks after the surgical intervention), and T₂ (postoperatively at 6–9 months).

Results

A statistically significant higher length of the ABDM was noted postoperatively, at T₁ and T₂ compared to T₀. The patients showed an increased length by 12.2% at 2 weeks postoperatively and continued to increase, reaching 24.6% at 6 months. A decreased width of ABDM by 6.5% at T₁ compared with T₀ was also found.

Conclusions

Postoperative ultrasound (US) follow-up measurements in patients with Class II malocclusion, orthognathic surgery and intraoperative BTX-A injection in the ABDM, showed dimensional changes of the muscle, with elongation and thinning. The muscular modifications were more pronounced at 6 months postoperatively, indicating consistency and potential benefit of using BTX-A in reducing the risk of surgical relapse. Further data on longer-term follow-up and larger number of cases are necessary.

     

Prevalence of Candida albicans and carriage of Candida non-albicans in the saliva of preschool children,according to their caries status

Objective: This study was conducted to establish associations among the Candida carriage rate, the diversity of Candida species carried and the different caries status of preschool children.

Materials and methods: Sixty-one children between 2 and 5 years of age were examined by a single expert examiner and were divided into three groups, the caries-free, moderate caries and severe caries groups, according to the criteria of the International Caries Detection and Assessment System II (ICDAS). Saliva samples were obtained from the members of each group and were plated on Sabouraud agar plates to assess the Candida carriage rates. CHROMagar Candida medium was used for the preliminary screening. Biochemical testing or PCR/sequencing was conducted to identify the different Candida species in the samples. The differences observed were considered significant if the p value was <0.05.

Results: The Candida carriage rate and the number of species of this fungus carried were higher in the group with the highest level of caries severity (p?Candida albicans was the most predominant Candida species in the saliva of all of the children, C. dubliniensis was identified only in the most caries-affected group in addition to other rare species of Candida non-albicans.

Conclusions: A high salivary Candida carriage rate and the presence of specific species of this fungus (such as C. albicans and C. dubliniensis) appear to be related to the severity of caries experienced by preschool children.     

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

Aims: Oral candidiasis is a major oral manifestation of uncontrolled diabetes mellitus, and a number of cofactors are associated with the pathogenesis of this infection. Here, we describe the prevalence of oral Candida in a Sri Lankan cohort of type 2 diabetes mellitus and risk factors that predispose them to this common fungal infection.

Methods: A case–control study was conducted in 250 diabetics with type 2 diabetes and 81 nondiabetic controls. Clinical and demographic data were collected using an interviewer administered questionnaire, and patient records. Oral rinse samples were collected to determine the candidal carriage, and the resultant yeast growth was quantified and speciated using multiplex-PCR and phenotypic analyses. Chi-square test (χ² test) and Fisher exact test were used for the determination of the significant relationships between risk factors and oral candidiasis.

Results: The oral prevalence of Candida species among both groups was similar (81%) although a significantly higher proportion of diabetics (32.8%) yielded >2000 CFU/mL of yeasts compared with only 12.3% of the healthy controls (p?p?C.albicans was the most common Candida species isolated followed by C. parapsilosis, C. tropicalis and C. glabrata.

Conclusions: The oral infestation of Candida in our Sri Lankan cohort of diabetics is significantly higher than their healthy counterparts, and co-carriage of multiple yeast species is a common finding in the study population. As there are no previous such reports of the latter phenomenon particularly from the Asian region it is noteworthy, mainly in view of the recent data on the emergence of drug-resistant yeast species the world over.     

Early and long-term changes in the muscles of the mandible following orthognathic surgery

Objectives

The aim of the present study is to evaluate the early and long-term postoperative dimensional changes of the muscles of the mandible in patients with orthognathic surgery for class II and class III malocclusions by using ultrasonography (US).

Material and methods

Twenty-six patients who underwent bimaxillary orthognathic surgery for class II or class III malocclusions (14 and 12 patients, respectively) were ultrasonographically examined. The length, width, and cross-sectional area of the masseter and suprahyoid muscles were measured at three different time points: T₀ (preoperatively), T₁ (early postoperatively at 1 month after the surgery), and T₂ (late postoperatively at 9 months). A repeated measures ANOVA was used to calculate statistically significant dimensional changes of the mandibular muscles.

Results

Statistically significant dimensional changes were found postoperatively in class II malocclusion patients only. The digastric muscle showed higher values for the length and lower values for the width (p < .05) at T₁. The geniohyoid muscles were higher in length at T₁ and lower in cross-sectional area (CSA) (p < .05) at T₂. A decreased measured length and an increased measured width were found in case of the mylohyoid muscle (p < .05) at T₂. The early and long-term postoperative dimensional changes of the masseter muscle were not statistically significant.

Conclusions

The mandibular muscles showed a variable adaptive response to the orthognathic surgery. US should be considered for the long-term follow-up of muscular dimensional changes in class II malocclusion patients.

Clinical relevance

From a clinical perspective, US is a reliable, non-invasive, and widely available method, which allows monitoring the postoperative muscular changes occurring in class II malocclusion patients.

     

Does the Presence of Anterior Mandibular Teeth Increase the Incidence of Denture Stomatitis?

Purpose : To compare the frequency of denture stomatitis (DS) under maxillary complete dentures (CDs) in patients with opposing mandibular distal extension removable partial dentures (RPDs) and CDs. Materials and Methods : Participants included 365 maxillary CD wearers (241 women, mean age 70.5 ± 13.2 years; 124 men, mean age 71.5 ± 10.4 years) from 7 rest homes in Istanbul. A total of 268 had mandibular CDs; 97 had mandibular distal extension RPDs. Two independent, calibrated examiners performed oral examinations. Presence of maxillary denture‐related stomatitis and the effect of risk factors on DS were evaluated and recorded. Results : The frequency of palatal DS (Newton I‐III) was 45.1% (n = 121) in the mandibular CD group and 49.5% (n = 48) in the mandibular distal extension RPD group, a statistically insignificant difference (p= 0.4). Factors significantly associated with palatal DS were maxillary denture age (p= 0.02), reduced occlusal vertical dimension (p= 0.04), and nocturnal denture wear (p= 0.03). Conclusion : In this study, DS beneath maxillary CDs did not differ between mandibular distal extension RPD and CD wearers. The presence of mandibular anterior teeth did not influence the occurrence of palatal DS.     

Erosive potential of soy-based beverages on dental enamel

Background: This study aimed to investigate the erosive potential of soy-based beverages in comparison to fruit juices of the same flavor.

Methods: Human enamel blocks were randomly divided into 9 groups (n?=?8), according to the beverage category (soy or non-soy juices). The initial pH, TA and β at the original pH value were measured in triplicate. The composition of calcium, phosphate and total protein was analyzed using the specific colorimetric method. The fluoride analysis was performed using a selective electrode. The degree of saturation (DS) and the critical pH (CpH) of each beverage with respect to hydroxyapatite (HAp) and fluorapatite (FAp) were calculated using the computational software. Enamel samples were immersed into 67.5?mL of each drink for 120?minutes. Enamel surface loss (ESL) and differences in surface roughness (ΔRa_E-S) were analyzed by a 3D non-contact profilometer.

Results: Non-soy beverages exhibited the lowest pH values (2.93 to 3.40). The highest values of calcium concentration were founded in soy-based formulations. Juices with soy in their composition tend to have high DS when compared with non-soy based beverages (p?=?.0571). Soy beverages produced less ESL than non-soy beverages (p?<?.05). ΔRa_E-S was not significantly different between the categories. The ESL and ΔRa_E-S were positively correlated with initial pH and buffering capacity in soy-based beverages. On the other hand, in non-soy beverages, the ESL was negatively correlated with the TA to 7.0 and the fluoride composition whereas the ΔRa_E-S was negatively correlated with the TA to 5.5.

Conclusions: The erosive potential of soy beverages was lower than non-soy based beverages.     

Reducing the Incidence of Denture Stomatitis: Are Denture Cleansers Sufficient?

Purpose: Candida albicans is the predominant oral yeast associated with denture stomatitis. With an increasing population of denture wearers, the incidence of denture stomatitis is increasing. Effective management of these patients will alleviate the morbidity associated with this disease. The aim of this study was to examine the capacity of four denture cleansers to efficiently decontaminate and sterilize surfaces covered by C. albicans biofilms. Materials and Methods: Sixteen C. albicans strains isolated from denture stomatitis patients and strain ATCC 90028 were grown as mature confluent biofilms on a 96‐well format and immersed in Dentural, Medical? Interporous^®, Steradent Active Plus, and Boots Smile denture cleansers according to the manufacturers’ instructions or overnight. The metabolic activity and biomass of the biofilms were then quantified, and scanning electron microscopy (SEM) used to examine treated biofilms. Results: Dentural was the most effective denture cleanser, reducing the biomass by greater than 90% after 20 minutes. Steradent Active plus was significantly more effective following 10‐minute immersion than overnight (p < 0.001). All cleansers reduced the metabolic activity by greater than 80% following overnight immersion; however, Boots Smile exhibited significantly reduced metabolic activity following only a 15‐minute immersion (p < 0.001). SEM revealed residual C. albicans material following Dentural treatment. Conclusions: This study showed that denture cleansers exhibit effective anti‐C. albicans biofilm activity, both in terms of removal and disinfection; however, residual biofilm retention that could lead to regrowth and denture colonization was observed. Therefore, alternative mechanical disruptive methods are required to enhance biofilm removal.     

Influence of surface characteristics on the adhesion of Candida albicans to various denture lining materials

Abstract

Objective. This study evaluated the influence of surface characteristics of various denture lining materials on the adherence of Candida albicans. Materials and methods. Four different types of materials (tissue conditioners, acrylic and silicone soft liners and hard reline materials) were selected. Disk-shaped material specimens were prepared and their surface roughness values (R_a ) measured using a profilometer. The contact angles of four reference liquids were measured on the material surfaces and surface energy parameters (total surface energy, acid and base components, degree of hydrophobicity/hydrophilicity) of the materials were calculated in accordance with acid-base theory. Specimens were incubated with C. albicans and adhering fungi quantified using the colony counting method. Data were statistically analyzed using a one-way ANOVA with Games–Howell post-hoc test (α = 0.05). Pearson correlation analysis was applied to detect correlations between surface characteristics and Candida adhesion. Results. Significant differences in the surface roughness of the materials were found (p < 0.001). The acrylic soft liners were more hydrophilic than the other materials. Overall, the acrylic soft liners and tissue conditioners showed significantly greater Candida adhesion than silicone soft liners and hard reline materials (p < 0.05). The Pearson correlation analysis indicated that the base component and degree of hydrophobicity/hydrophilicity of the materials (p = 0.005/0.008), rather than the total surface energy and the surface roughness (p = 0.093/0.057), affected C. albicans adherence in a statistically significant way. Conclusions. The adhesion of C. albicans to denture lining materials can be accounted for in terms of interfacial acid-base interactions.     

Candida infection in oral leukoplakia: an unperceived public health problem

Objectives: The study aimed to determine the proportion, known risk factors and etiology for Candida infection in leukoplakia lesions among patients with oral leukoplakia attending the Oral and Maxillofacial Clinic at a Tertiary Care Hospital in Sri Lanka.

Materials and methods: Eighty clinically suspected oral leukoplakia patients were included. Two oral swabs each, from leukoplakia patients: one swab from the lesion and the other one from the contralateral unaffected corresponding area (as a control) were collected. Direct microscopy and culture followed by colony count and phenotypic identification were performed to identify pathogenic Candida species.

Results: Candida infection was seen in 47% of patients with oral leukoplakia. Candida albicans (94.7%) was the most common Candida species followed by Candida tropicalis (5.3%). Majority of Candida-infected lesions were seen in the buccal mucosa region. Alteration of taste (p?=?0.021), having other oral lesions (p?=?0.008), angular cheilitis (p?=?0.024) and periodontitis (p?=?0.041) showed a significant association with Candida-associated leukoplakia. Increasing age showed a significant tendency for Candida infection (p?=?0.020). Smoking (p?=?0.026) and betel-quid chewing (p?=?0.006) were also found to be significantly associated, although alcohol consumption alone did not show a significant association. Oral leukoplakia patients who had all three habits: alcohol consumption, smoking and betel-quid chewing had a significant association with Candida infection (p?=?0.004).

Conclusions: Patients who had a combination of risk factors: smoking, betel-quid chewing and alcohol consumption were seen to have a significant association with Candida infection. Further betel-quid chewing alone and smoking singly was also significantly associated with Candida infection in oral leukoplakia.     

Effectiveness of non-fluoride and fluoride dentifrices for denture hygiene

Objective: To compare the effectiveness of commonly used herbal/non-fluoride with fluoride dentifrices in order to eliminate pathogenic oral microorganisms from denture base material.

Materials and methods: Heat-polymerized acrylic resin specimens (n?=?288) were divided into three groups and each group inoculated with three various microorganisms (n?=?96 for each) Candida albicans, Staphylococcus aureus and Pseudomonas aeruginosa (P. aeruginosa). Contaminated specimens were randomly assigned to the application of six herbal/non-fluoride and three fluoride dentifrices. These specimens were divided into two groups: negative and positive control (n?=?3 for each). All acrylic specimens were incubated at 37?°C for 24?h for samples inoculated with bacterial strains and 37?°C for 48?h for samples inoculated with yeast strains. After the incubation period, all brain–heart infusion broths that contained disinfectant acrylic specimens were cultured on 5% sheep blood agar for bacterial counts and Sabouraud dextrose agar for yeast counts. The number of colony-forming units per millilitre (CFU/mL) were calculated. The results were analysed by Mann–Whitney U and Kruskal–Wallis tests (p?=?.05).

Results: Both herbal/non-fluoride and fluoride dentifrices were effective against Candida albicans. However, fluoride dentifrices were comparatively better than the herbal/non-fluoride dentifrices against Staphylococcus aureus and P. aeruginosa.

Conclusions: Herbal dentifrices could be used, especially among the elderly who lack a degree of manual dexterity during the rinsing of dentifrice chemicals from their dentures.     

The antimicrobial properties,cytotoxicity, and differentiation potential of double antibiotic intracanal medicaments loaded into hydrogel system

Objective

This study evaluated the antimicrobial properties, cytotoxicity, and mineralization potential of methylcellulose hydrogels loaded with low concentrations of double antibiotic pastes (DAP).

Materials and methods

The direct and residual antibacterial effects of 1, 5, and 10 mg/mL of DAP loaded into hydrogels as well as calcium hydroxide (Ca(OH)₂) were tested against single-species biofilms of Enterococcus faecalis and dual-species biofilms (Enterococcus faecalis and Prevotella intermedia). The effects of DAP hydrogels on proliferation and mineralization of dental pulp stem cells (DPSC) were tested using MTT assays, alkaline phosphate activity (ALP), and alizarin red staining. Fisher’s exact tests, Wilcoxon rank sum tests, and one-way ANOVA were used for statistical analyses (α = 0.05).

Results

All tested concentrations of DAP hydrogels as well as Ca(OH)₂ demonstrated significant direct antibacterial effects against single- and dual-species biofilms. However, only 5 and 10 mg/mL of DAP hydrogels exhibited significant residual antibacterial effects against both types of tested biofilms. Only 1 mg/mL of DAP hydrogels did not have significant negative effects on DPSC viability, ALP activity, and mineralization nodule formation. However, 5 and 10 mg/mL of DAP hydrogels caused significant negative effects on cytotoxicity and mineralization nodule formation of DPSC.

Conclusions

Hydrogels containing 1 mg/mL DAP offered significant direct antibacterial effects against single- and dual-species biofilms without causing significant negative effects on viability, ALP activity, and mineralization nodule formation of DPSC.

Clinical relevance

The methylcellulose-based hydrogel proposed in this study can be used clinically as a biocompatible system to deliver controlled low concentrations of DAP.

     

Investigation of bacteremia after debonding procedures

Objective: The purpose of this study is to investigate the effect of debonding procedures after completion of orthodontic treatments on bacteremia.

Materials and methods: Twenty-eight patients who were treated with fixed orthodontic treatment at the Faculty of Dentistry’s Department of Orthodontics at Gaziantep University and who had an indication of debonding were selected for this study, and blood samples were taken from these patients at different times and examined for bacteremia. Blood culture samples were taken from the antecubital veins of the patients prior to debonding (T₀), immediately after removing the bracket (T₁), and immediately after cleaning the composite residues and plaque deposits on the enamel surface (T₂). The blood samples were then inoculated in blood culture bottles and investigated for bacterial growth.

Results: The results showed that there was no bacterial growth in the blood samples taken at T₀ and T₁, whereas 10 of the blood culture samples taken at T₂ showed bacterial growth including the following bacteria; Streptococcus viridans, Streptococcus mitis, Streptococcus parasanguinis, Streptococcus salivarius, Streptococcus oralis, Staphylococcus aureus, Actinomyces oris, Actinomyces naeslundii and Klebsiella pneumoniae.

Conclusion: It was concluded that patients in the risk group could develop bacteremia during debonding procedures. The presence of these bacteria in sterile blood suggested the possibility of bacterial endocarditis.     

Color Stability of Resins and Nylon as Denture Base Material in Beverages

Purpose: Staining of prosthodontic materials may result in patient dissatisfaction and additional expense for replacement. This study aimed to determine the color stability of two heat‐cured denture base acrylic (Lucitone 550, Vipi Cril) and one nylon denture base resin (Transflex) after immersion in beverages. Materials and Methods: Forty disks of each resin (20.0‐mm diameter, 3.0‐mm thick) were prepared and stored in distilled water for 24 hours at 37°C. During that time (T₀), the color of all specimens was spectrophotometrically measured. Each specimen was immersed in coffee, cola, red wine, and distilled water as a means of control. After 15‐day (T₁) and 30‐day (T₂) periods of immersion, the color of the specimens was measured again. The CIE (Commission Internationale de L’ Eclairage) L*a*b* system was used to determine mean ΔE (color changes) values for each material and compared statistically with two‐way ANOVA and Bonferroni intervals at 0.95. Results: In ΔET₀T₁ and ΔET₀T₂ the most severe staining was apparent with red wine (p < 0.001), followed by coffee (p < 0.01), when compared to the specimens stored in distilled water. Transflex also showed significant color change after immersion in cola (p < 0.01). In ΔET₁T₂ only red wine promoted significant staining of all resins (p < 0.0001). Conclusion: Chromatic changes were exhibited by specimens immersed in red wine, followed by coffee. For Transflex, cola also promoted color changes. The values of color changes converted to National Bureau of Standard units showed them to be perceivable to the human eye.     

Comparative analysis of Candida spp. isolated from complete denture wearers with and without an HIV diagnosis

Statement of problemDenture-related stomatitis (DRS), an inflammation frequently present in human immunodeficiency virus-positive (HIV+) individuals, can be attributable to colonization by Candida spp., which is considered a main factor. The virulence factors of these species are often modulated by the systemic condition of their hosts.PurposeThe purpose of this clinical study was to evaluate the incidence, virulence, and morphology of Candida spp. isolated from biofilms of complete denture wearers with DRS, with and without an HIV diagnosis. In addition, the interaction of the systemic condition with the ability of Candida spp. to colonize was evaluated.Material and methodsFifty-five complete denture wearers diagnosed with DRS were divided into 2 groups: experimental (HIV+) and control (human immunodeficiency virus-noninfected participants [HIV-]). Biofilm was collected by a standardized method of ultrasonification of prostheses. The incidence was evaluated by a chromogenic method and polymerase chain reaction (PCR). The virulence factors were assessed by using the capacity for biofilm formation by counting colony-forming units (CFUs/mL), biofilm metabolism by tetrazolium salt metabolization, and proteinase and phospholipase production by using a fluorimetric kit. Morphology was verified by using the hyphae-inducing test, and participants’ health data were collected with a form. Data were analyzed by using the Student t, Mann-Whitney U, Spearman, and Fisher tests (α=.05).ResultsThe results of incidence were related to 55 participants (22 experimental and 33 control); in total, 63 Candida spp. samples were isolated, showing 28 Candida albicans and 36 nonalbicans strains. No significant difference was found between groups in baseline CFU/mL counts, biofilm formation capacity, cell metabolism, and phospholipase production. Proteinase production was higher for C. albicans in the control (P=.031) and for nonalbicans in the experimental (P=.016) groups. Relative to health data, the experimental group showed a moderate negative correlation between the CFU count/mL at baseline for nonalbicans and DRS classification (P=.020).ConclusionsC. albicans was the most prevalent species. No difference was found in the Candida spp. of complete denture wearers with DRS, with and without an HIV diagnosis, with regard to virulence factors (except for proteinase production) and morphology.     

Clinical and Histological Findings of Denture Stomatitis as Related to Intraoral Colonization Patterns of Candida albicans,Salivary Flow,and Dry Mouth

Purpose: Multifactorial etiological factors contribute to denture stomatitis (DS), a type of oral candidiasis; however, unlike other oral candidiasis, DS can occur in a healthy person wearing a denture. In this study, we therefore attempt to explore the association between candida, denture, and mucosal tissue using (1) exfoliative cytology, (2) the candidal levels present in saliva, on mucosal tissues and on denture surfaces, and (3) the salivary flow rate and xerostomic symptoms. Materials and Methods: A cross‐sectional study enrolled 32 edentulous participants, 17 without DS as controls and 15 with DS (Newton's classification type II and III). Participants with systemic or other known oral conditions were excluded. Participants completed a xerostomia questionnaire, and salivary flow rates were measured. Samples of unstimulated whole saliva (UWS) and stimulated whole saliva (SWS) were collected. UWS was used for fungal culturing. Periodic acid‐Schiff (PAS) stain and quantitative exfoliative cytology were performed on samples from affected and unaffected mucosa from each participant. Levels of Candida species (albicans and non‐albicans) were determined in salivary samples (expressed as colony‐forming units, CFU), as well as from swab samples obtained from denture fitting surfaces, in addition to affected and unaffected mucosa. Results: There were no significant differences in salivary flow rates, mucosal wetness, or frequency of reported dry mouth comparing participants with and without DS. Exfoliative cytology of mucosal smears demonstrated significantly higher (p= 0.02) inflammatory cell counts in DS patients, as compared with smears of healthy denture‐wearers. Candida albicans was significantly more prevalent in saliva (p= 0.03) and on denture surfaces (p= 0.002) of DS participants, whereas mucosal candidal counts and the presence of cytological hyphae did not show significant difference comparing DS to healthy participants. Conclusions: In this investigation, we presented a unique group of healthy edentulous patients. This population may reflect the general DS population without systemic or other oral diseases. The prominent etiological factor for DS in this population is the presence of candida in denture and saliva. We found that other factors such as saliva flow/xerostomia, fitting of the denture, and the presence of candida in the mucosa, are less important in this population. Therefore, DS treatments in healthy patients should first focus on sanitization of an existing denture and/or fabrication of a new denture.