Persistence of epoxy-based sealer residues in dentin treated with different chemical removal protocols

The presence of residual endodontic sealer in the pulp chamber may cause discoloration of the dental crown and interfere with the adhesion of restorative materials. The aim of this study was to compare the efficacy of different solvents in removing residues of an epoxy resin-based sealer (AH Plus) from the dentin walls of the pulp chamber, by scanning electron microscopy (SEM). Forty-four bovine incisor dental crown fragments were treated with 17% EDTA and 2.5% NaOCl. Specimens received a coating of AH Plus and were left undisturbed for 5 min. Then, specimens were divided in four groups (n = 10) and cleaned with one of the following solutions: isopropyl alcohol, 95% ethanol, acetone solution, or amyl acetate solution. Negative controls (n = 2) did not receive AH Plus, while in positive controls (n = 2) the sealer was not removed. AH Plus removal was evaluated by SEM, and a score system was applied. Data were analyzed by Kruskal-Wallis and Dunn tests. None of the solutions tested was able to completely remove AH Plus from the dentin of the pulp chamber. Amyl acetate performed better than 95% ethanol and isopropyl alcohol (p < 0.05), but not better than acetone (p > 0.05) in removing the sealer from dentin. No significant differences were observed between acetone, 95% ethanol, and isopropyl alcohol (p > 0.05). It was concluded that amyl acetate and acetone may be good options for cleaning the pulp chamber after obturation with AH Plus. SCANNING 35:17-21, 2013. © 2012 Wiley Periodicals, Inc. © Wiley Periodicals, Inc.

In vitro antimicrobial activity of auxiliary chemical substances and natural extracts on Candida albicans and Enterococcus faecalis in root canals

Objective: The aim of this study was to evaluate the antimicrobial activity of auxiliary chemical substances and natural extracts on Candida albicans and Enterococcus faecali's inoculated in root canals. Material and Methods: Seventy-two human tooth roots were contaminated with C. albicans and E. faecalis for 21 days. The groups were divided according to the auxiliary chemical substance into: G1) 2.5% sodium hypochlorite (NaOCl), G2) 2% chlorhexidine gel (CHX), G3) castor oil, G4) glycolic Aloe vera extract, g5) glycolic ginger extract, and G6) sterile saline (control). The samples of the root canal were collected at different intervals: confirmation collection, at 21 days after contamination; 1st collection, after instrumentation; and 2nd collection, seven days after instrumentation. Microbiological samples were grown in culture medium and incubated at 37°C for 48 hours. Results: The results were submitted to the Kruskal-Wallis and Dunn (5%) statistical tests. NaOCl and CHX completely eliminated the microorganisms of the root canals. Castor oil and ginger significantly reduced the number of CFU of the tested bacteria. Reduction of CFU/mL at the 1st and 2nd collections for groups G1, G2, G3 and G4 was greater in comparison to groups G5 and G6. Conclusion: It was concluded that 2.5% sodium hypochlorite and 2% chlorhexidine gel were more effective in eliminating C. albicans and E. faecalis, followed by the castor oil and glycolic ginger extract. The Aloe vera extract showed no antimicrobial activity.

Effect of the root canal final rinse protocols on the debris and smear layer removal and on the push-out strength of an epoxy-based sealer

The aim of the present study was to evaluate the efficacy of QMiX, SmearClear, and 17% EDTA for the debris and smear layer removal from the root canal and its effects on the push-out bond strength of an epoxy-based sealer by scanning electron microscopy (SEM). Forty extracted human canines (n=10) were assigned to the following final rinse protocols: G1-distilled water (control), G2-17% EDTA, G3-SmearClear, and G4-QMiX. The specimens were submitted to a SEM analysis to evaluate the presence of debris and smear layer, respectively, in the apical or cervical segments. In sequence, forty extracted human maxillary canines with the root canals instrumented were divided into four groups (n=10) similar to the SEM analysis study. After the filling with AH Plus, the roots were transversally sectioned to obtain dentinal slices. The specimens were submitted to a push-out bond strength test using an electromechanical testing machine. The statistical analysis for the SEM and push-out bond strength studies were performed using the Kruskal-Wallis and Dunn tests (α=5%). There was no difference among the G2, G3, and G4 efficacy in removing the debris and smear layer (P>0.05). The efficacy of these groups was superior to the control group. The push-out bond strength values of G2, G3, and G4 were superior to the control group. The ability to remove the debris and smear layer by SmearClear and QMiX was as effective as the 17% EDTA. The final rinse with these solutions promoted similar push-out bond strength values. © 2013 Wiley Periodicals, Inc.

Disproportionate pregnancy-induced myocardial hypertrophy in women with essential hypertension

BACKGROUND Pregnancy and arterial hypertension (AH) have a prohypertrophic effect on the heart. It is suspected that the 2 conditions combined cause disproportionate myocardial hypertrophy. We sought to evaluate myocardial hypertrophy (LVH) and left ventricular function in normotensive and hypertensive women in the presence or absence of pregnancy.METHODS This prospective cross-sectional study included 193 women divided into 4 groups: hypertensive pregnant (HTP; n = 57), normotensive pregnant (NTP; n = 47), hypertensive nonpregnant (HTNP; n = 41), and normotensive nonpregnant (NTNP; n = 48). After clinical and echocardiographic evaluation, the variables were analyzed using 2-way analysis of variance with pregnancy and hypertension as factors. Left ventricular mass (LVM) was compared using nonparametric analysis of variance and Dunn′s test. Predictors of LVH and diastolic dysfunction were analyzed using logistic regression (significance level, P < 0.05).RESULTS Myocardial hypertrophy was independently associated with hypertension (odds ratio (OR) = 11.1, 95% confidence interval (CI) = 3.2-38.5; P < 0.001) and pregnancy (OR = 6.1, 95% CI = 2.6-14.3; P < 0.001) in a model adjusted for age and body mass index. Nonpregnant women were at greater risk of LVH in the presence of AH (OR = 25.3, 95% CI = 3.15-203.5; P = 0.002). The risk was additionally increased in hypertensive women during pregnancy (OR = 4.3, 95% CI = 1.7-10.9; P = 0.002) in the model adjusted for stroke volume and antihypertensive medication. Although none of the NTNP women presented with diastolic dysfunction, it was observed in 2% of the NTP women, 29% of the HTNP women, and 42% of the HTP women (P < 0.05).CONCLUSIONS Hypertension and pregnancy have a synergistic effect on ventricular remodeling, which elevates a woman's risk of myocardial hypertrophy. © 2013 © American Journal of Hypertension, Ltd 2013. All rights reserved.

The effects of different styles of musical auditory stimulation on cardiac autonomic regulation in healthy women

The literature investigated the effects of chronic baroque music auditory stimulation on the cardiovascular system. However, it lacks in the literature the acute effects of different styles of music on cardiac autonomic regulation. To evaluate the acute effects of baroque and heavy metal music on heart rate variability (HRV) in women. The study was performed in 21 healthy women between 18 and 30 years old. We excluded persons with previous experience with music instrument and those who had affinity with the song styles. All procedures were performed in the same sound-proof room. We analyzed HRV in the time (standard deviation of normal-to-normal respiratory rate (RR) intervals, root-mean square of differences between adjacent normal RR intervals in a time interval, and the percentage of adjacent RR intervals with a difference of duration greater than 50 ms) and frequency (low frequency [LF], high frequency [HF], and LF/HF ratio) domains. HRV was recorded at rest for 10 min. Subsequently they were exposed to baroque or heavy metal music for 5 min through an earphone. After the first music exposure they remained at rest for more 5 min and them they were exposed again to baroque or heavy metal music. The sequence of songs was randomized for each individual. The power analysis provided a minimal number of 18 subjects. Shapiro-Wilk to verify normality of data and analysis of variance for repeated measures followed by the Bonferroni test for parametric variables and Friedman's followed by the Dunn's post-test for non-parametric distributions. During the analysis of the time-domain indices were not changed. In the frequency-domain analysis, the LF in absolute units was reduced during the heavy metal music stimulation compared to control. Acute exposure to heavy metal music affected the sympathetic activity in healthy women.

Effect of Zingiber officinale and propolis on microorganisms and endotoxins in root canals

The purpose of this study was to evaluate the effectiveness of glycolic propolis (PRO) and ginger (GIN) extracts, calcium hydroxide (CH), chlorhexidine (CLX) gel and their combinations as ICMs (ICMs) against Candida albicans, Enterococcus faecalis, Escherichia coli and endotoxins in root canals. Material and Methods: After 28 days of contamination with microorganisms, the canals were instrumented and then divided according to the ICM: CH+saline; CLX, CH+CLX, PRO, PRO+CH; GIN; GIN+CH; saline. The antimicrobial activity and quantification of endotoxins by the chromogenic test of Limulus amebocyte lysate were evaluated after contamination and instrumentation at 14 days of ICM application and 7 days after ICM removal. Results and Conclusion: After analysis of results and application ofthe Kruskal-Wallis and Dunn statistical tests at 5% significance level, it was concluded that all ICMs were able to eliminate the microorganisms in the root canals and reduce their amount of endotoxins; however, CH was more effective in neutralizing endotoxins and less effective against C. albicans and E. faecalis, requiring the use of medication combinations to obtain higher success.

Antibiofilm activity, pH and solubility of endodontic sealers

Aim: To evaluate antibiofilm activity against Enterococcus faecalis, pH and solubility of AH Plus, Sealer 26, Epiphany SE, Sealapex, Activ GP, MTA Fillapex (MTA-F) and an experimental MTA-based Sealer (MTA-S). Methodology: Sealer samples were manipulated and stored for 2 or 7 days. Prepared sealers were evaluated by a modified direct contact test (DCT) for 5 h, 10 h or 15 h with biofilm previously induced on bovine dentine for 14 days. In the control group, the biofilm was not exposed to the sealers. The number of colony-forming units (CFU mL-1) in the remaining biofilm was determined. Sealer solubility was assessed by the percentage of mass loss after 15 h of immersion in distilled water. Sealer pH was measured at 5 h, 10 h and 15 h. Statistical analysis was performed using Kruskal-Wallis and Dunn or anova and Tamhane's T2 tests, at 5% significance. Results: At 2 days post-manipulation, the DCT showed that Sealapex and MTA-F were associated with a reduction in the number of bacteria in all 3 contact periods evaluated, compared with the control group (P < 0.05). At 7 days, Sealapex had the greatest antibiofilm action at 10 h and 15 h. Sealapex had the highest pH values 2 and 7 days post-manipulation. Regarding the solubility, at 2 days the highest values were observed for MTA-F, MTA-S, Sealapex and Activ GP (P < 0.05). At 7 days, MTA-S and MTA-F had greater solubility than the other materials (P < 0.05). AH Plus had the lowest solubility for both post-manipulation periods (P < 0.05). Conclusion: Sealapex and MTA-F were associated with a reduction in the number of bacteria in biofilms and had greater solubility. The high solubility and pH may be related to the antibacterial activity of these materials. © 2012 International Endodontic Journal.

Comparison of the accuracy for three dental impression techniques and index: An in vitro study

Objectives: This in vitro study compared the dimensional accuracy of stone index (I) and three impression techniques: tapered impression copings (T), squared impression copings (S) and modified squared impression copings (MS) for implant-supported prostheses. Methods: A master cast, with four parallel implant abutment analogs and a passive framework, were fabricated. Vinyl polysiloxane impression material was used for all impressions with two metal stock trays (open and closed tray). Four groups (I, T, S and MS) were tested (n = 5). A metallic framework was seated on each of the casts, one abutment screw was tightened, and the gap between the analog of implant and the framework was measured with a stereomicroscope. The groups' measurements (80 gap values) were analyzed using software (LeicaQWin - Leica Imaging Systems Ltd.) that received the images of a video camera coupled to a Leica stereomicroscope at 100× magnification. The results were statistically analyzed with Kruskal-Wallis One Way ANOVA on Ranks test followed by Dunn's Method, 0.05. Results: The mean values of abutment/framework interface gaps were: Master Cast = 32 μm (SD 2); Group I = 45 μm (SD 3); Group T = 78 μm (SD 25); Group S = 134 μm (SD 30); Group MS = 143 μm (SD 27). No significant difference was detected among Index and Master Cast (P = .05). Conclusion: Under the limitations of this study, it could be suggested that a more accurate working cast is possible using tapered impression copings techniques and stone index. © 2013 Japan Prosthodontic Society.

Setting Time Affects In Vitro Biological Properties of Root Canal Sealers

Introduction: Biocompatibility of root canal sealers is important because of the long-term contact of their eluates and/or degradation products with periapical tissues. The literature still lacks studies about the genotoxic effects of these materials and the influence of setting time on biological properties. The cytotoxicity and genotoxicity of an epoxy resin-based sealer (AH Plus), a single methacrylate-based sealer (EndoRez), and a silicone-based sealer (RoekoSeal) were assessed. Methods: Chinese hamster fibroblasts (V79) were cultured and exposed to different dilutions of extracts from the sealers that were left to set for 0, 12, and 24 hours before contact with culture medium. Cell viability was measured by the methyl-thiazol-diphenyltetrazolium assay. Genotoxicity was assessed by the comet assay. Data were statistically analyzed by Kruskal-Wallis and Dunn tests (P < .05). Results: Root canal sealers were statistically more cytotoxic than the untreated control group, except for the silicon-based sealer. Cell viability ranking was the following (from the most to the least cytotoxic): methacrylate-based > epoxy resin-based > silicone-based. The setting time influenced the epoxy resin-based sealer cytotoxicity (decreased at 12 hours) and the general genotoxicity (increased at 24 hours). DNA damage ranking was the following (from the most to the least genotoxic): methacrylate-based > silicone-based = epoxy resin-based. Conclusions: The setting time had influence on the cytotoxicity of the epoxy resin-based sealer and genotoxicity of all tested sealers. The methacrylate-based sealer was the most cytotoxic, and the silicone-based sealer was not cytotoxic. Genotoxicity was observed for all sealers. © 2013 American Association of Endodontists.

Effect of final irrigation protocols on microhardness and erosion of root canal dentin

The aim of this study was to evaluate the effect of final irrigation protocols (17% EDTA, BioPure MTAD, SmearClear, and QMiX) on microhardness and erosion of root canal dentin. Fifty roots were sectioned transversely at the cement-enamel junction and each root was sectioned horizontally into 4-mm-thick slices. The samples were divided into five groups (n=10) according to the final irrigation protocol: G1: distilled water (control group); G2: 17% EDTA; G3: BioPure MTAD; G4: SmearClear; and G5: QMiX. The dentin microhardness was then measured with a load of 25 g for 10 s. Initially, the reference microhardness values were obtained for the samples without any etching. The same samples were then submitted to the final irrigation protocols. A new measure was realized and the difference between before and after the procedures was the dentin microhardness reduction. In sequence, the specimens were submitted to SEM analysis to verify the dentinal erosion. The Kruskal Wallis and Dunn tests (α=5%) were used to compare the results. The dentin microhardness decreased for all final irrigation protocols. There was no significant difference between groups 2, 3, 4, and 5 (P>0.05), but this groups presented significant dentin microhardness reduction than G1 (P<0.05). In G2, occurred the highest incidence of dentinal erosion (P<0.05). 17% EDTA, BioPure MTAD, SmearClear, and QMiX promoted significant dentin microhardness reduction. © 2013 Wiley Periodicals, Inc.

Disinfection protocols to prevent cross-contamination between dental offices and prosthetic laboratories

Control of cross-contamination between dental offices and prosthetic laboratories is of utmost importance to maintain the health of patients and dental office staff. The purpose of this study was to evaluate disinfection protocols, considering antimicrobial effectiveness and damage to the structures of prostheses. Solutions of 1% sodium hypochlorite, 2% chlorhexidine digluconate, 50% vinegar and sodium perborate were evaluated. Specimens were contaminated in vitro with standardized suspensions of Candida albicans, Streptococcus mutans, Escherichia coli, Staphylococcus aureus and Bacillus subtilis spores. Disinfection by immersion for 10. min was performed. Final counts of microorganisms were obtained using the plating method. Results were statistically compared by Kruskal-Wallis ANOVA and Dunn's test. The surface roughness of 40 specimens was analyzed before and after 10 disinfection cycles, and results were compared statistically using Student's t test. The solution of 50% vinegar was as effective as 1% sodium hypochlorite and 2% chlorhexidine against C. albicans, E. coli and S. mutans. The sodium perborate solution showed the lowest antimicrobial effectiveness. Superficial roughness increased after cycles in 1% sodium hypochlorite (p=0.02). Solutions of 1% sodium hypochlorite, 2% chlorhexidine and 50% vinegar were effective for the disinfection of heat-polymerized acrylic specimens. Sodium hypochlorite increased the superficial roughness. © 2013 King Saud Bin Abdulaziz University for Health Sciences.

Ropivacaína isolada ou associada à morfina, butorfanol ou tramadol pela via peridural em cadelas para realização de ovariosalpingohisterectomia

Pós-graduação em Ciência Animal - FMVA

Prevalência e suscetibilidade aos antibióticos de enterococcus spp. isoladas da cavidade bucal humana

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Associação de enterococcus faecalis, candida albicans e escherichia coli em canais radiculares e avaliação dos efeitos de extratos naturais sobre os microrganismos e endotoxinas

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Detecção de microrganismos em bráquetes metálicos in vivo, com ou sem utilização de agente antimicrobiano, pela técnica Checkerboard DNA-DNA Hybridization

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)