Effect of staining and denture cleaning on color stability of differently polymerized denture base acrylic resins

Background

Denture hygiene is an important factor to remove dental plaque and discoloration, to provide optimal oral health, and to prevent denture stomatitis.

Aim

The purpose of this study was to evaluate the effect of coffee staining and denture cleaner on the color stability of two differently polymerized (heat and microwave) denture acrylic resin in vitro.

Materials and Methods

Two commonly used denture base acrylic resins and effervesecnt tablet form denture cleaner were used in this study. Disc-shaped specimens from each acrylic resin were polymerized according to the manufacturer's instructions (n = 7). Color values were recorded before and after immersion in distilled water (I), denture cleaner (II), coffee (III), and coffee + denture cleaner (IV) with a tristimulus colorimeter using CIEDE2000 color difference formula. Two-way analysis of variance (ANOVA) and Fisher's least significant difference tests were used for multiple comparisons at a 95% confidence level (P < 0.05). Surface topography of the acrylic resin denture base specimens before and after immersion were taken under 500 × magnification.

Results

The two-way ANOVA revealed significant interactions between denture base resins and solutions (P < 0.001). Immersion in denture cleaner and coffee solution caused significant color changes in acrylic resin denture bases.

Conclusion

Heat- and microwave-polymerized acrylic denture base resins can show different color stability. Immersion in coffee and denture cleaner solutions can cause noticeable color changes.

Differentiation of Entamoeba histolytica and Entamoeba dispar by PCR: a preliminary study in Izmir, Turkey

The causative agent of amoebiasis is currently attributed to two distinct species (E. histolytica and E. dispar). The aim of this study was to differentiate these species by PCR in stool samples. Isolated genomic DNA was amplified by PCR and band products of 101 bp (E. dispar) were obtained. All seven stool samples were found to be E. dispar, not E. histolytica. Our results demonstrated the significance of E. histolytica/dispar differentiation in the diagnosis of amoebiasis. This study is preliminary to our current research project entitled "Investigation of the prevalence of amoebiasis and Entamoeba species in Izmir and its hinterland".

Interleukin (IL) 5 levels and eosinophilia in patients with intestinal parasitic diseases

AIM

Intestinal parasitic diseases are commonly accompanied with diarrhoeal symptoms and allergic reactions. Eosinophilia occurs as a result of IL-5 synthesized from Th2 cells during allergic reactions. IL-5 acts as a factor activating eosinophils. The aim of this study was to compare the IL-5 cytokine measurements in serum samples and cell cultures. And also to compare eosinophilia observed in helminth infections and protozoon infections accompanied with allergy.

METHODS

Twenty-three patients who presented with diarrhoeal symptoms and allergic complaints were tested positive for intestinal parasites, as well as 21 controls with allergic complaints who did not have any intestinal parasites were included in this study. IL-5 production in in vitro cell cultures prepared by using phytohemaglutinin (PHA) to stimulate peripheral blood mononuclear cells (PBMC) obtained from the blood samples taken from these patients were compared with the IL-5 level in serum. Furthermore, the IL-5 production in protozoon and helminth infections was also compared. Absolute eosinophil values in 1 mm(3) of blood were calculated by means of peripheral smear in both groups within the scope of the study.

RESULTS

Parasites such as helminth detected in 15 (65.2%) and protozoon in 8 (34.8%) of the patients were included in this study. As regards the values of the sera in both patients with parasite infection and controls, the IL-5 production was found to be higher in the cell culture supernatant (P<0.001 and P<0.05). When the IL-5 level of the patients with helminth parasites was compared with that of those with protozoon, it was determined that the IL-5 level in serum was more significant in the patients with protozoon than in those with helminth (P<0.05). In the study group, the patients were found to have parasites, the percentage of eosinophil was 7.0% compared to 6.5% in the control group. Thus, there was no significant difference between the eosinophil values (P>0.05).

CONCLUSION

It was found that IL-5 cytokine levels in serum samples from the patients with helminth and protozoon displayed more measurable values as compared to the IL-5 levels after stimulation with mitogen. It is concluded that IL-5 acts as a triggering factor in the toxiallergic complaints commonly seen in helminth and protozoon infections.

Effect of human milk and colostrum on Entamoeba histolytica

AIM: Many defense factors of the mother’s colostrum or milk protect infants from intestinal, respiratory and systemic infections. In the present study, we investigated the effect of colostrum and mature human milk on E. histolytica parasites in vitro.

METHODS: Samples of human milk were collected from 5 healthy lactating mothers. The medium with human milk at concentrations of 2%, 5% and 10% was obtained.

RESULTS: The lethal effect of E. histolytica on the medium supplemented with different concentrations of both colostrum and mature human milk was significant during the first 30 min. We also detected that the results of colostrum and mature human milk were similar. No statistically significant differences were found between same concentrations of colostrum and mature human milk at the same times.

CONCLUSION: Colostrum and mature human milk have significant lethal effect on E. histolytica and protect against its infection in breast fed children.

Frequency of toxoplasmosis in patients with cirrhosis

AIM: It is known that toxoplasmosis rarely leads to various liver pathologies, most common of which is granulomatose hepatitis in patients having normal immune systems. Patients who have cirrhosis of the liver are subject to a variety of cellular as well as humoral immunity disorders. Therefore, it may be considered that toxoplasmosis can cause more frequent and more severe diseases in patients with cirrhosis and is capable of changing the course of the disease. The aim of this study was to investigate the frequency of toxoplasmosis in patients with cirrhosis.

METHODS: Serum samples were taken from 108 patients with cirrhosis under observation in the Hepatology Polyclinic of the Gastroenterology Clinic, and a control group made up of 50 healthy blood donors. IFAT and ELISA methods were used to investigate the IgG and IgM antibodies, which had developed from these sera.

RESULTS: Toxoplasma IgG and IgM antibody positivity was found in 74 (68.5%) of the 108 cirrhotic patients and 24 (48%) of the 50 people in the control group. The difference between them was significant (P < 0.05).

CONCLUSION: In conclusion, it was found that the toxoplasma sero-prevalence in the cirrhotic patients in this study was higher. Cirrhotic patients are likely to form a toxoplasma risk group. More detailed studies are needed on this subject.

Effects of Cd+2, Cu+2, Ba+2 and Co+2 ions on Entamoeba histolytica cysts

AIM: The effects of cobalt, copper, cadmium and barium ions on the cysts of Entamoeba histolytica (E. histolytica), an amebic dysentery agent, cultured in Robinson medium were investigated.

METHODS: E. histolytica cysts and trophozoites isolated from a patient with amebiasis were cultivated in the medium, incubated at 37 °C for a period of 4 days and 40 × 10⁴/ml amebic cysts were then transferred to a fresh medium. At the second stage, 0.05, 0.1 and 0.2 mM of selected metal ions were added to the medium, and the effects of these ions on parasitic reproduction compared with the control group were observed.

RESULTS: It was determined that the number of living parasites in all the groups containing metal ions decreased significantly starting from 30 minutes (P < 0.01). CuCl₂ showed the highest lethal effect on E. histolytica cysts, whereas the lowest lethal effect was observed with CoCl₂. It was also seen that the number of living cells was decreased as the ion concentration and exposure time were increased, and that there were no living parasites in the medium at the end of 24 h (P < 0.01).

CONCLUSION: It may be stated that the effect of ever-increasing contamination of the environment with metal waste materials on parasites should be investigated further.

Prevalence of amebiasis in inflammatory bowel disease in Turkey

AIM: To explore the prevalence of amebiasis in inflammatory bowel disease (IBD) in Turkey.

METHODS: In this study, amoeba prevalence in 160 cases of IBD, 130 of ulcerative colitis and 30 of Crohn’s disease were investigated in fresh faeces by means of wet mount+Lugol’s iodine staining, modified formol ethyl acetate and trichrome staining methods and to compare the diagnostic accuracy of wet mount+Lugol’s iodine staining, modified formol ethyl acetate and trichrome staining methods in the diagnosis of Entamoeba histolytica (E. histolytica)/ Entamoeba dispar (E. dispar).

RESULTS: E. histolytica/E. dispar cysts and trophozoites were found in 14 (8.75%) of a total of 160 cases, 13 (10.0%) of the 130 patients with ulcerative colitis and 1 (3.3%) of the 30 patients with Crohn’s disease. As for the 105 patients in the control group who had not any gastrointestinal complaints, 2 (1.90%) patients were found to have E. histolytica /E. dispar cysts in their faeces. Parasite prevalence in the patient group was determined to be significantly higher than that in the control group (Fischer’s Exact Test, P < 0.05). When the three methods of determining parasites were compared with one another, the most effective one was found to be trichrome staining method (Kruskal-Wallis Test, P < 0.01).

CONCLUSION: Consequently, amoeba infections in IBD cases have a greater prevalence compared to the normal population. The trichrome staining method is more effective for the detection of E. histolytica /E. dispar than the wet mount+Lugol’s iodine staining, modified formol ethyl acetate methods.

Protozoon infections and intestinal permeability

Intestinal permeability (IP) studies using some macromolecules have been assumed to demonstrate the intactness of intestinal mucosa. The aim of the present study is to determine the changes in IP among patients with protozoan infections. Thirty nine patients with protozoan infections and ten healthy controls were enrolled in the study. Protozoa were diagnosed by Native-lugol, Richie and Trichrome staining of faeces. IP was evaluated by diethyl triamine penta acetic acid labeled with 99m Technetium (99mTc labeled DTPA) assay. The IP was found to have increased in patients with protozoan infections compared with control patients (7.20+/-5.52 vs. 4.47+/-0.65%, P=0.0017). The IP values were 9.91+/-10.05% in Giardia intestinalis group, 6.81+/-2.25% in Blastocystis hominis group, 5.78+/-2.84% in Entamoeba coli group. In comparison with the control group, the IP was significantly higher in G. intestinalis and B. hominis patients (P=0.0025, P=0.00037, respectively), but not in E. coli patients. In conclusion, the IP increases in patients with G. intestinalis and B. hominis but not with E. coli infection. This finding supports the view that IP increases during the course of protozoan infections which cause damage to the intestinal wall while non-pathogenic protozoan infections have no effect on IP. The increase in IP in patients with B. hominis brings forth the idea that B. hominis can be a pathogenic protozoan.