Osman Erganis

In vitro antibacterial activities of root-canal sealers by using two different methods.

The purpose of this in vitro study was to evaluate the antibacterial activity of five different root-canal sealers (RoekoSeal, Ketac-Endo, AH Plus, Sealapex, Sultan). With the use of Enterococcus faecalis as a test organism, both the agar-diffusion test (ADT) and direct-contact test (DCT) were performed. For DCT, sealers were mixed and placed on the sidewall of microtiter plate wells. A 10-microl bacterial suspension was placed on the tested material samples. Bacteria were allowed to directly contact to the sealers for 1 h at 37 degrees C. Bacterial growth was then spectrophotometrically measured through every 30 min for 19 h by using an Anthos Labtec HT 2. For ADT, a 200-microl bacterial suspension was spread on brain-heart infusion agar plates. Freshly mixed sealers were poured into uniform wells punched in the agar. After periods of incubation at 37 degrees C for 24 h and 7 days in humid atmosphere, the zones of inhibition of bacterial growth on agar plates were observed and measured. Ketac-Endo, Sultan, and AH Plus had similar results for DCT. These sealers were more potent bacterial-growth inhibitors than Sealapex and RoekoSeal. According to ADT, RoekoSeal showed no antibacterial activity. There was no significant difference among AH Plus, Sealapex, and Sultan (p > 0.05). Ketac-Endo demonstrated lower antimicrobial activity than these sealers (p < 0.05). Time had no effect on the antibacterial activity of the tested sealers (p > 0.05). The antibacterial efficiency of the materials varied according to the tests used. It was concluded that the technique, time, and ingredients of the tested material can affect the results of the microbiological studies.

Comparison of antibacterial activity of two dentin bonding systems using agar well technique and tooth cavity model

OBJECTIVE This study compared the antibacterial activities of two dentin bonding systems (ABF, Kuraray and Reactmer Bond, Shofu) by a conventional agar well technique and a newly designed in vitro test using tooth model. METHODS In the agar well technique, the test materials were filled in the wells of Muller Hinton agar plates inoculated with Streptococcus mutans NCTC10449, and the diameters of inhibition zones produced around the materials were measured after 24h of incubation. For the tooth model test, three cavities (diameter 1mm, depth 2mm) were prepared in the flat occlusal dentin of human extracted molar. After sterilization, the teeth were left in broth culture of 1.56 x 10(8)CFU/ml of S. mutans at 37 degrees C for 72h for allowing bacteria to invade the cavity. The dentin bonding systems were applied separately to each of the two infected cavities, and the third cavity was left unapplied for control. After sealing the occlusal surfaces, the teeth were kept in physiologic saline solution at 37 degrees C for 72h. The standardized amounts of dentin chips (120+/-5mg) were obtained from the cavity walls and the number of bacteria recovered was determined. The results were analyzed by One Way ANOVA, Kruskal Wallis and Mann-Whitneys U tests. RESULTS The primer of ABF and Reactmer Bond produced inhibition zones with similar sizes (p>0.05), but the bonding resin of ABF did not produce any inhibition. When tested by the model cavity method, the application of ABF resulted in significantly less bacterial recovery than Reactmer Bond (p<0.05), demonstrating substantial antibacterial effects. CONCLUSIONS The tooth model method used in this study was effective for evaluating the substantial antibacterial effects of dentin bonding agents, and the experimental dentin bonding system ABF was demonstrated to be able to inactivate the bacteria in the cavity effectively in comparison with little antibacterial activity shown by Reactmer Bond.

A comparative study on detection of Ornithobacterium rhinotracheale antibodies in meat-type turkeys by dot immunobinding assay, rapid agglutination test and serum agglutination test

The objectives of the present study were to develop a dot-immunobinding assay (DIA) and a serum agglutination test (SAT) for detection of Ornithobacterium rhinotracheale , to compare the rapid agglutination test (RAT) and the SAT, and to make a serosurvey of O. rhinotracheale exposure on turkey farms in Turkey. Antiserum against O. rhinotracheale bacterin was prepared in rabbits and 72 serum samples were collected from turkeys with respiratory signs on four farms. Comparison of the tests showed that 55.5, 48.6 and 40.3% of serum samples were positive by RAT, SAT and DIA, respectively. The sensitivity of the DIA appeared to be lower than that of the agglutination tests but the specificity is not known.

Hemagglutination, Hydrophobicity, Enterotoxigenicity, and Drug-Resistance Characteristics of Avian Escherichia coli

A total of 35 Escherichia coli isolates obtained from necropsy materials of hens with septicemia in the Konya region of Turkey were examined for hemagglutination (HA), cell-surface hydrophobicity, enterotoxigenicity, and drug resistance. HA tests were performed on live cultures with human (group A), bovine, avian (chicken), and guinea pig erythrocytes with and without mannose. Nine HA patterns were observed. Of the 35 isolates, 62.8% exhibited mannose sensitive hemagglutination (MSHA), 8.6% exhibited mannose resistant hemagglutination (MRHA), and 28.6% did not hemagglutinate. Of the isolates, 85.7% were hydrophobic by a salt aggregation test (SAT). Only three isolates were enterotoxigenic by a suckling mouse assay. The majority of the isolates were resistant to chloramphenicol, tetracycline, streptomycin, ampicillin, erythromycin, and trimethoprim + sulfamethoxazole but were highly sensitive to gentamicin and nalidixic acid.

Rapid diagnosis of ovine Brucella, Campylobacter and Salmonella infections from fetal stomach contents by coagglutination test

Abstract A coagglutination test (CT) was developed to detect Brucella , Campylobacter and Salmonella antigens in stomach contents of 58 aborted sheep fetuses and compared with conventional culture techniques. Brucella melitensis , Campylobacter fetus and Salmonella abortus ovis were isolated from 31 (53.4%), 13 (22.4%) and 4 (6.9%) fetuses, respectively. Thirty-five of the fetal stomach contents were positive with the CT test, including 19 (61.3%) with Brucella , 12 (92.3%) with Campylobacter and 4 (100%) with Salmonella CT tests, respectively. Seven samples were negative with all three CT reagents. Cross-reactions were seen with C ampylobacter CT (11 samples) and S almonella CT (six samples). The sensitivity and specificity of the CT tests were 61 and 80% for Brucella , 92 and 80% for Campylobacter , and 100 and 90% for Salmonella , respectively. The CT was found to be technically simple and rapid in diagnosing Salmonella , Campylobacter or Brucella infections by comparison with conventional culture methods.

Bacterial penetration of restored cavities using two self-etching bonding systems

Objective: The aim of this study was to investigate the effects of two bonding systems, with and without antibacterial monomers, on marginal bacterial and dye leakage. Materials and Methods: Class V cavities were prepared in extracted teeth for a bacterial leakage test, and the teeth were sterilized using a steam autoclave. Four cavities were not restored for the controls, and the other teeth were divided into two groups (n = 16 cavities each): Clearfil Protect Bond group (CPB) and Clearfil SE Bond group (CSE). After application of the bonding agent, the cavities were restored using a composite resin (Clearfil AP-X). The teeth were thermocycled, stored in a broth culture of 1.56 Χ 108 colony forming units (CFU)/ml of Streptococcus mutans at 37°C for 10 days, and subsequently processed for bacterial staining. Sections from the demineralized teeth were evaluated under a light microscope. In the dye leakage test, the cavities were restored as described in the bacterial penetration test. After thermocycling, the teeth were immersed in 5% basic fuchsin for 24 h, and then divided in half and observed under a stereomicroscope. The data were analyzed using the Kruskal-Wallis and Mann-Whitney U-tests (P = 0.05). Results: The bacterial stain was detected at the cavity wall of five cavities in both bonding systems. Additionally, two cavities in the CSE group, one cavity in the CPB group, and all control cavities showed bacterial staining within the cut dentinal tubules. Dye staining at the axial cavity wall was detected in only three of the teeth for both bonding systems. Conclusion: The bonding systems used in this study provided an acceptable marginal seal to prevent bacterial and dye leakage.

Comparison of five methods for isolation of DNA from Mycoplasma cynos

Extraction of DNA from Mycoplasma cultured on agar medium is difficult because the plasticity of these microorganisms enables agar penetration. This eventually causes cell loss during harvesting of colonies from the agar surface. Here, we used the GenElute™ gel extraction kit, which is usually used to purify polymerase chain reaction products, for extracting DNA from Mycoplasma. We compared the DNA extraction efficiency of the GenElute™ gel extraction kit from Mycoplasma cynos cultured in agar medium with four other DNA extraction methods. The results were evaluated based on the purity and amount of DNA obtained from one Mycoplasma colony. Eight strains of Mycoplasma cynos isolated from the broncho-alveolar lavage fluid of dogs were used. The GenElute™ gel extraction protocol was the most efficient among all the methods tested in this study as it yielded the highest amount and the purest quality of DNA (199.3±0.744ng/μl) from a single colony. Among the methods tested, the GenElute™ gel extraction method is the most rapid, sensitive, and simple method for DNA extraction from Mycoplasma. This procedure may also prove useful for extracting DNA from other Mycoplasma species.