Mebendazole treatment against Anacanthoras penilabiatus (Monogenea, Dactylogyridae) gill parasite of cultivated Piaractus mesopotamicus (Osteichthyes, Characidae) in Brazil. Efficacy and hematology

The present work evaluated the efficacy of mebendazole (MBZ) treatment against infections with the monogenean helminths Anacanthorus penilabiatus, gill parasites of young cultivated pacu, Piaractus mesopotamicus. A short-term bath treatment using 100, 200 and 500 mg MBZ/l of water for 10 and 30 min and a long-term-bath using 1, 10 and 100 mg MBZ/l of water for 24 h were utilized. Seven days after, fish were sacrificed and parasites counted. Concentrations of 500 and 200 mg MBZ/l for 10 and 30 min showed reduced efficacy (0.0 and 0.7%) and (14.2 and 11.0%), respectively. Nevertheless, 100 mg MBZ/l (10 min) and 10 nag MBZ/l (24 h) showed better efficacy (79.6 and 8 1.4%, respectively). Treatments for 24 h provoked increases in hematocrit, hemoglobin concentration and leukocyte number when compared to those untreated fish. Mebendazole treatments also provoked alterations in the defense blood cells especially in lymphocyte and thrombocyte numbers, when the fishes were submitted to 10 and 30 min baths.

Biocompatibility of different intracanal medications in rat buccal submucosa tissue

The aim of this study was to analyze the buccal tissue responses of Wistar rats to 2% chlorhexidine solution, calcium hydroxide and the association of both products. For this purpose, 30 specimens were randomly implanted in the filtrum of the four upper and lower hemiarches with a polyethylene tube containing one of the following substances: 2% chlorhexidine solution, calcium hydroxide and 2% chlorhexidine solution (test groups); calcium hydroxide and distilled water and distilled water (control groups). Ten rats each were distributed according to time interval of evaluation at 7, 15 and 30 days. The histological sections were stained with Harris hematoxylin and eosin. Analysis was per-formed with an optical microscope at x100, x200 and x400 magnifications by an expert examiner blinded to the materials. The sections were classified by scores attributed to inflammatory events and by a ranking determined according to the severity of the inflammation. The results of the inflammatory events and severity ranking were submitted to the Kruskal-Wallis test at a 0.05 level of significance. No statistically significant difference occurred among the tested materials; however, all materials showed a decreased of severity with respect to longer time intervals.

Hydrogenated amorphous carbon as protective coating for a forming tool

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Shielding quantum discord through continuous dynamical decoupling

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Influence of antimicrobial subinhibitory concentrations on hemolytic activity and bacteriocin-like substances in oral: Fusobacterium nucleatum

Fusobacterium nucleatum is considered for its role in colonization of initial and late microorganisms in dental plaque and for its coaggregation with other bacterial species. It is known that action of different antimicrobial substances may interfere with either virulence factors or with host-bacteria interaction. The goal of this study was to examine the influence of subinhibitory concentrations of chlorhexidine, triclosan , penicillin G and metronidazole on hemolytic activity and bacteriocin-like substance production of oral F. nucleatum. A high resistance to penicillin G was observed and 63% of the isolates were β-lactamase positive. All the tested isolates were susceptible to metronidazole. F. nucleatum isolates grown with or without antimicrobials were alpha-hemolytics. Bacteriocin-like substance production was increased in isolates grown with penicillin G. Impaired production of hemolytic or antagonic substances can suggest a role in the regulation of oral microbiota.

In vitro evaluation of the antimicrobial activity of a castor oil-based irrigant

The antimicrobial activity of irrigating solutions - Endoquil (castor oil detergent), 2% chlorhexidine gluconate solution, and 0.5% NaOCI solution - was evaluated against Gram-positive cocci (Micrococcus luteus, Staphylococcus aureus, Enterococcus faecalis, Staphylococcus epidermidis, Streptococcus mutans, and Streptococcus sobrinus), Gramnegative rods (Escherichia coli and Pseudomonas aeruginosa), and the yeast Candida albicans. Activity was evaluated using the two-layer agar diffusion technique. The base layer was obtained by pouring 10.0 ml of Muller Hinton Medium or 10.0 ml of Brain Heart Infusion agar in a Petri dish. After solidification a 5.0 ml seed layer of Muller Hinton Medium or Brain Heart Infusion agar with inoculum (106/ml) was added. Absorbent paper disks (6.0 mm in diameter) immersed in the solutions were placed at equidistant points. Plates were maintained at room temperature for 2 h for prediffusion of the solutions and incubated at 37°C for 24 h. The candle jar system was used for the Brain Heart Infusion agar plates. All tests were performed in duplicate. After incubation the medium was optimized with 0.05 g% triphenyltetrazolium chlorate gel and inhibition halos were measured. All bacterial strains were inhibited by 2.0% chlorhexidine gluconate. Endoquil was effective against Grampositive microorganisms, and 0.5% NaOCI was effective only against S. aureus. Copyright © 2001 by The American Association of Endodontists.

Mebendazole treatment against Anacanthorus penilabiatus (Monogenea, Dactylogyridae) gill parasite of cultivated Piaractus mesopotamicus (Osteichthyes, Characidae) in Brazil. Efficacy and hematology

The present work evaluated the efficacy of mebendazole (MBZ) treatment against infections with the monogenean helminths Anacanthorus penilabiatus, gill parasites of young cultivated pacu, Piaractus mesopotamicus. A short-term bath treatment using 100, 200 and 500 mg MBZ/1 of water for 10 and 30 min and a long-term bath using 1, 10 and 100 mg MBZ/1 of water for 24 h were utilized. Seven days after, fish were sacrificed and parasites counted. Concentrations of 500 and 200 mg MBZ/1 for 10 and 30 min showed reduced efficacy (0.0 and 0.7%) and (14.2 and 11.0%), respectively. Nevertheless, 100 mg MBZ/1 (10 min) and 10 mg MBZ/1 (24 h) showed better efficacy (79.6 and 81.4%, respectively). Treatments for 24 h provoked increases in hematocrit, hemoglobin concentration and leukocyte number when compared to those untreated fish. Mebendazole treatments also provoked alterations in the defense blood cells especially in lymphocyte and thrombocyte numbers, when the fishes were submitted to 10 and 30 min baths.

Evaluation of marginal microleakage in Class II cavities: Effect of microhybrid, flowable, and compactable resins

Objective: The goal of the present study was to evaluate the microleakage on the cementum/dentin and enamel surfaces in Class II restorations, using different kinds of resin composite (microhybrid, flowable, and compactable). Method and materials: Forty human caries-free molars were extracted and selected. Eighty Class II standardized cavities were made in the cervical wall at the cementoenamel junction (CEJ) and at the mesial and distal surfaces. The teeth were divided into four groups: G1 - adhesive system + microhybrid resin composite Z100; G2 - adhesive system + compactable resin composite Prodigy Condensable; G3 - adhesive system + flowable resin composite Revolution + Z100 resin composite; G4 - adhesive system + Revolution fluid resin + compactable resin composite Prodigy Condensable. The adhesive system used in this study was Scotchbond Multi-Purpose Plus. The specimens were thermocycled in baths of 5°C and 55°C for 1,000 cycles and immersed in 50% silver nitrate solution. The specimens then were sectioned and evaluated on degree of dye penetration. Results: The results were evaluated using the nonparametric Kruskall-Wallis test, which showed a statistically significant difference between groups G1 and G4, G2 and G4, and G3 and G4. Conclusions: None of the materials was able to eliminate the marginal microleakage at the cervical wall; the application of a low-viscosity resin composite combined with a compactable resin composite significantly decreased the microleakage.

Lethal photosensitization in microbiological treatment of ligature-induced peri-implantitis: a preliminary study in dogs

This pilot study evaluated, by culture testing, the effectiveness of lethal photosensitization for the microbiological treatment of peri-implantitis in dogs. Experimental peri-implantitis was induced by ligature placement for 2 months. Following ligature removal, plaque control was instituted by scrubbing with 0.12% chlorhexidine daily for 12 months. Subsequently, mucoperiosteal flaps were elevated for scaling the implant surface. Microbial samples were obtained with paper points before and after treatment of implant surfaces by means of 100 microg/ml toluidine blue O (TBO,) and were exposed, for 80 s, to light with a wavelength of 685 nm from a 50 mW GaAlAs diode laser. The mean initial and final bacterial counts were 7.22 +/- 0.20 and 6.84 +/- 0.44 CFU/ml, respectively for TVC (P < 0.0001); 6.19 +/- 0.45 and 3.14 +/- 3.29 CFU/ml for P. intermedia/nigrescens (P = 0.001); 5.98 +/- 0.38 and 1.69 +/- 2.90 CFU/ml for Fusobacterium spp. (P = 0.001); and 6.07 +/- 0.22 to 1.69 +/- 2.94 CFU/ml for beta-hemolytic Streptococcus (P = 0.0039). It may be concluded that lethal photosensitization resulted in a reduction of the bacterial count. Complete elimination of bacteria was achieved in some samples.

Smear layer removal capacity of disinfectant solutions used with and without EDTA for the irrigation of canals: a SEM study.

The purpose of this study was to carry out a scanning electron microscopic (SEM) analysis of the cleaning qualities and smear layer removal from root canal walls, instrumented and irrigated with 2.5% NaOCl, 2.0% chlorhexidine and saline solutions. Fifty extracted teeth were used in this study. All teeth were radiographed to determine the existence of a single canal. The crowns were cut at the cervical limit and the root canals were instrumented with K-type files up to size 45. During root canal preparation, irrigations were made with the different solutions being evaluated: Group 1: 2.5% NaOCl (10 roots); Group 2: 2.5% NaOCl and 17% EDTA for 2 minute (10 roots); Group 3: 2.0% chlorhexidine (10 roots); Group 4: 2.0% chlorhexidine and 17% EDTA for 2 minutes (10 roots); Group 5: saline solution (5 roots); Group 6: saline solution and 17% EDTA for 2 minutes (5 roots). After instrumentation, the canals were irrigated with each one of the solutions and the roots were cut in the buccolingual direction for SEM analysis, at the cervical, middle and apical thirds, to ascertain the presence or absence of smear layer and debris. SEM analysis was performed by three calibrated examiners and scores were submitted to Kruskal-Wallis test at the significance level of p = 5%. Results showed that the use of 17% EDTA decreased the smear layer significantly (p < 0.05) for all evaluated solutions in all thirds. When EDTA was not used, a significantly higher quantity of smear layer on the apical third was observed only in the NaOCl groups. The use of 17% EDTA was significant for debris removal except for the chlorhexidine groups. The following conclusion could be drawn: the use of 17% EDTA was necessary to enhance cleanness of the root canals.

Effect of Arnica montana 6 cH on edema, mouth opening and pain in patients submitted to extraction of impacted third molars

This study had the objective to evaluate the homeopathic action of Arnica montana 6 cH and placebo on edema, mouth opening (trismus) and pain in patients submitted to extraction of bilaterally impacted lower third molars. The experiment was carried out as a crossover and double-blind study. The data showed that edema was significantly reduced by the treatment with Arnica montana 6 cH (p<0.05) and did not demonstrate significant effect on trismus and pain as compared to control group.

Inhibitory activity of glass-ionomer cements on cariogenic bacteria

This study evaluated the antibacterial activity of the glass-ionomer cements Vitrebond (3M ESPE), Ketac Molar (3M ESPE) and Fuji IX (GC America) against S mutans, S sobrinus, L acidophilus and A viscosus, using the agar diffusion test. Inocula were obtained by the seed of indicators cultures in BHI broth incubated at 37°C for 24 hours. Base layers containing 15 mL of BHI agar and 300 μL of each bacteria suspension were prepared in Petri dishes. Six wells measuring 4 mm in diameter were made in each plate and completely filled with one of the testing materials. A 0.2% chlorhexidine solution applied in round filter papers was used as control. Tests were performed 12 times for each material and bacteria strain. After incubation of the plates at 37°C for 24 hours, the zones of bacterial growth inhibition around the wells were measured. Overall, the results showed the following sequence of antibacterial activity: Vitrebond (despite the activation mode) > 0.2% chlorhexidine > Ketac Molar > Fuji IX, according to Kruskal-Wallis and Mann-Whitney statistical tests. This study confirmed significant antibacterial activity for two conventional glass-ionomers and one resin-modified glass-ionomer material. The resin-modified glass-ionomer cement Vitrebond, regardless of the activation mode, presented the best antibacterial activity against S mutans and S sobrinus. The antibacterial activity against A viscosus for Vitrebond was similar to 0.2% chlorhexidine, while light activation reduced its antibacterial activity against L acidophilus. ©Operative Dentistry, 2005.

Effect of disinfectants on the hardness and roughness of reline acrylic resins

Purpose: Potential effects on hardness and roughness of a necessary and effective disinfecting regimen (1% sodium hypocholorite and 4% chlorhexidine) were investigated for two hard chairside reline resins versus a heat-polymerizing denture base acrylic resin. Materials and Methods: Two standard hard chairside reliners (Kooliner and Duraliner II), one heat-treated chairside reliner (Duraliner II +10 minutes in water at 55°C), and one standard denture base material (Lucitone 550) were exposed to two disinfecting solutions (1% sodium hypochlorite; 4% chlorhexidine gluconate), and tested for two surface properties [Vickers hardness number (VHN, kg/mm2); Roughness (Ra, μm)] for different times and conditions (1 hour after production, after 48 hours at 37 ± 2°C in water, after two disinfection cycles, after 7 days in disinfection solutions, after 7 days in water only). For each experimental condition, eight specimens were made from each material. Data were analyzed by analysis of variance followed by Tukey's test, and Student's t-test (p= 0.05). Results: For Kooliner (from 6.2 ± 0.3 to 6.5 ± 0.5 VHN) and Lucitone 550 (from 16.5 ± 0.4 to 18.4 ± 1.7 VHN), no significant changes in hardness were observed either after the disinfection or after 7 days of immersion, regardless of the disinfectant solution used. For Duraliner II (from 4.0 ± 0.1 to 4.2 ± 0.1 VHN), with and without heat treatment, a small but significant increase in hardness was observed for the specimens immersed in the disinfectant solutions for 7 days (from 4.3 ± 0.2 to 4.8 ± 0.5 VHN). All materials showed no significant change in roughness (Kooliner: from 0.13 ± 0.05 to 0.48 ± 0.24 μm; Duraliner II, with and without heat treatment: from 0.15 ± 0.04 to 0.29 ± 0.07 μm; Lucitone 550: from 0.44 ± 0.19 to 0.49 ± 0.15 μm) after disinfection and after storage in water for 7 days. Conclusions: The disinfectant solutions, 1% sodium hypochlorite and 4% chlorhexidine gluconate, caused no apparent damage on hardness and roughness of the materials evaluated. Copyright © 2006 by The American College of Prosthodontists.

In vivo microbiological evaluation of the effect of biomechanical preparation of root canals using different irrigating solutions

The aim of this study was to evaluate the antimicrobial effect of biomechanical preparation using different irrigating solutions. Seventy-eight root canals from premolars of four dogs were used. After experimental induction of periapical lesions, the root canals were prepared using the following solutions for irrigation: Group 1) 2.5% sodium hypochlorite (NaOCl); Group 2) 2% chlorhexidine (CHX); Group 3) saline solution and Group 4) control group with no biomechanical preparation. The microbiological evaluation of the root canals was performed by counting the colony forming units (CFUs) using different culture mediums. Two absorbent paper cones were used in each root canal in order to collect the microbiological samples before, and thirty days after the biomechanical preparation. The culture plates were incubated in aerobic, anaerobic and microaerophilic environment. Statistical evaluation was carried out using analysis of variance, Tukey and Student tests. The results demonstrated that there was reduction in the number of microorganisms in the NaOCl and CHX groups (p<0.05). There was greater effectiveness in the chlorhexidine group. The group that used saline solution and the control group presented an increased number of microorganisms. It can be concluded that the use of antimicrobial irrigating solutions during biomechanical preparation promotes the reduction of endodontic microbiota. However, a considerable number of microorganisms were still observed.

Elimination of intracanal infection in dogs' teeth with induced periapical lesions after rotary instrumentation: Influence of different calcium hydroxide pastes

The aim of this study was to evaluate the antiseptic efficacy of rotary instrumentation associated with calcium hydroxide-based pastes prepared with different vehicles and antiseptics. Chronic periapical lesions were experimentally induced in 72 premolar root canals of four dogs. Under controlled asepsis, after initial microbiological sampling (A1), the root canals were instrumented using the ProFile system in conjunction with 5.25% sodium hypochlorite and the intracanal medication was placed. Four experimental groups were formed according to the pastes used: group 1- Calen (n=18), group 2- Calen+CPMC (n=20), group 3- Ca(OH)2 p.a.+ anaesthetic solution (n=16) and group 4- Ca(OH)2 p.a.+ 2% chlorhexidine digluconate (n=18). After 21 days, the pastes were removed; the canals were emptied and 96 hours later a second microbiological sample was obtained (A2). The incidence of positive microbiological cultures and the number of cfus in stages A1 and A2 were compared statistically by the Wilcoxon test while the influence of the different treatments in intracanal infection was evaluated by Kruskal-Wallis test at 5% significance level (p<0.05). Large numbers of strict and facultative anaerobes, and viridans group streptococci were found in 100% of root canals of A1 samples. Among A2 samples, all treatments showed significant reduction of cfus and positive cultures (p<0.05), but only groups 3 and 4 showed 100% of root canals free of microorganisms. Rotary instrumentation plus NaOCl 5.25% associated with intracanal medication produced a drastic reduction or elimination of intracanal microbiota, whose performance was not influenced by the nature of the vehicle or the antiseptic added to the Ca(OH)2 p.a.