Cutting efficiency of conventional and heat-treated nickel-titanium rotary or reciprocating glide path instruments.

AIM: To compare the cutting efficiency of several glide path files: HyFlex EDM Glidepath File (HEGF), One G (OG), R-Pilot (RP) and WaveOne Gold Glider (WOGG) at different cutting inclinations. METHODOLOGY: Cutting efficiency of 120 new HEGF, OG, RP and WOGG was tested at 90°, 70° and 45° inclination in relation to the sample. Depending on manufacturer instructions, instruments were tested in continuous rotation or reciprocating motion against standardized gypsum samples for 120 s using a customized apparatus. Cutting efficiency was determined by measuring the weight loss and the length of the sample cut. Data were analysed using two-way analysis of variance and Tukey t-test (P < 0.05). RESULTS: RP and WOGG had greater cutting ability than HEGF and OG in all tested angles. RP tested at 45° had significantly greater cutting efficiency than when tested at 90° and 70° (P < 0.05). OG was not significantly different in terms of cutting ability at 90°, 70° and 45° (P > 0.05). HEGF and WOGG had significantly greater cutting efficiency at 45° and 70° compared to 90° (P < 0.05), with no significant difference between 45° and 70° (P > 0.05). RP had the greatest cutting ability at all tested angles. CONCLUSIONS: Reciprocating glide path instruments had greater cutting efficiency compared to those in continuous rotation. An inclined insertion (45° or 70°) increased the cutting ability of glide path files except for One G conventional NiTi files.

Colorimetric study about the stratification's effect on colour perception of resin composites.

To evaluate the influence of a different order of dentin and enamel layers on stratification appearance of different resin composites. 144 Dentin (D) and Enamel (E) composite samples (Clearfil Majesty ES-2 Premium, Brilliant EverGlow, Estelite Asteria), 1 mm thick, were divided into 12 configurations for each composite, with Enamel-Dentin-Dentin-Enamel (EDDE) assumed as target. The colour specification was conducted using a spectrophotometer, elaborating the results with the CIE L*a*b* colour coordinates and calculating the colour difference in terms of [Formula: see text] quantity. A value of this last major of 3.3 was considered not clinically acceptable. Moreover, data were analyzed using two-way analysis of variance and Tukey post hoc test (P < 0.05). For Clearfil Majesty ES-2 Premium and Brilliant EverGlow, six configurations showed [Formula: see text] > 3.3 compared to gold standard EDDE. [Formula: see text] was influenced especially by b* and L* coordinates (P < 0.05). EDED showed no visual difference (0 < [Formula: see text] < 1.1) for both composites. For Estelite Asteria, two configurations reported [Formula: see text] > 3.3 compared to EDDE. In particular, the L* coordinate influenced [Formula: see text] results (P < 0.05). EDDD was the best configuration (0 < [Formula: see text] < 1.1). Within the limits of a vitro study, Brilliant EG showed more dependence from order and thickness of stratification (resulting more similar to Clearfil Majesty ES-2 Premium); therefore, it could be indicated for more complex aesthetic restorations. Estelite Asteria seems to be able to balance small differences in thickness of dentin and enamel layers, and consequently, it is more indicated to different clinical situations.

Influence of continuous rotation or reciprocation of Optimum Torque Reverse motion on cyclic fatigue resistance of nickel-titanium rotary instruments.

AIM: To evaluate the resistance to cyclic fatigue of ProTaper Next (PTN; Dentsply Sirona, Ballaigues, Switzerland), Revo-S (Micro-Mega, Besançon, France), Mtwo (Sweden & Martina, Padova, Italy), Twisted Files (TF, SybronEndo, Orange, CA, USA) and EndoWave (J Morita Corporation, Osaka, Japan) used in continuous rotation or in reciprocation of Optimum Torque Reverse motion (OTR). METHODOLOGY: A total of 120 nickel-titanium files were tested. Twenty-four instruments for each brand were divided into two groups (n = 12) on the basis of the motion tested: continuous rotation (Group 1) or reciprocation of OTR motion (Group 2). Resistance to cyclic fatigue was determined by recording time to fracture (TtF) in a stainless steel artificial canal with a 60° angle of curvature and 5 mm radius of curvature. The TtF data were analysed by using two-way analysis of variance (anova) and Bonferroni's post hoc tests at 0.05. RESULTS: Mtwo and TF had significantly higher TtF when compared with all other instruments, both in continuous rotation and in reciprocation of OTR motion (P < 0.0001 and P < 0.05, respectively). No difference was observed between Mtwo and TF (P > 0.05), in both motions. PTN was associated with higher cyclic fatigue resistance than Revo-S and EndoWave, both in continuous rotation and in reciprocation of OTR motions (P < 0.0001). No difference was observed between Revo-S and EndoWave, in both motions (P > 0.05). Reciprocating OTR motion improved TtF of all instruments (P < 0.0001). CONCLUSIONS: Reciprocation of OTR motion improved significantly cyclic fatigue resistance of all instruments tested compared with continuous rotation. Mtwo and TF had significantly higher cyclic fatigue than the other instruments, in both continuous rotation and reciprocation of OTR motion.

Evaluation of climatic factors on the yield and chemical composition of the essential oil of Myrocarpus frondosus.

The species Myrocarpus frondosus is native to southern Brazil, and it is known as cabreúva. It is a large tree, and its wood is used as a reservoir for distilled spirits, especially Cachaça. In this pioneering work, the essential oil was extracted monthly from the leaves of M. frondosus, for a period of 1 year. The essential oil was extracted by using hydrodistillation and the determination of the chemical composition of essential oil was performed by using the chromatographic techniques GC-FID and GC-MS. Thirty-three compounds were identified in the essential oil and bicyclogermacrene was the major compound. Through multivariate analysis, it was determined that ß-caryophyllene, limonene and terpinen-4-ol were directly proportional to climatic factors. The yield of the oil was directly proportional to temperature and radiation.

Mycobacterium tuberculosis at a comprehensive cancer centre: active disease in patients with underlying malignancy during 1990-2000.

Thirty HIV-seronegative cancer patients with active tuberculosis were evaluated. Eighteen (60%) were immigrants, 19 (63%) had haematological malignancy, and fever was the most common presentation (97%). Of 19 (63%) patients with pulmonary tuberculosis, 11 (58%) were misdiagnosed initially as suffering from cancer following radiography. Death was attributed to tuberculosis for six (21%) of 29 patients who received anti-mycobacterial therapy. All four patients who had received high-dose systemic corticosteroids within 4 weeks of diagnosis of infection died, whereas two (8%) deaths occurred in 25 individuals without corticosteroid exposure (p < 0.001; OR 8.67). At this institution, active tuberculosis was rare, and was seen mostly in immigrants. Recent high-dose corticosteroid therapy is a significant predictor of mortality in cancer patients with tuberculosis.

Risk factors for the development of invasive fungal infections in allogeneic blood and marrow transplant recipients.

Blood and marrow transplantation (BMT) is increasingly used to treat malignant and nonmalignant diseases. Despite significant advances in the management of transplant recipients, however, fungal infections remain important life-threatening complications of BMT. Over the past two decades, the incidence of fungal infections in this population has continued to rise. Several factors predispose BMT recipients to invasive fungal infections. These include but are not limited to use of intensive myeloablative chemotherapy and radiation therapy combined with prolonged granulocytopenia; development of acute and chronic graft-versus-host disease; administration of immunosuppressive therapy, particularly using corticosteroids; use of central venous catheters; and prolonged impairment of cell-mediated immunity secondary to the underlying disease and post-transplant immunodeficiency. Environmental factors also play a key part in the pathogenesis of fungal infections. Therefore, infection-control measures are critical to the prevention of such infections. In addition, although Candida and Aspergillus species are still the major culprits, other opportunistic fungi have emerged in recent years.

Native valve endocarditis due to Bartonella henselae in a middle-aged human immunodeficiency virus-negative woman.

We report the case of a human immunodeficiency virus-negative woman who developed native valve endocarditis of the aortic valve due to Bartonell henselae infection. The diagnosis was established using serology and PCR analysis of excised aortic valve tissue.

[Aortic valve replacement with pulmonary autograft (Ross procedure). Initial experience]. / Substituição da valva aórtica com auto-enxerto pulmonar (cirurgia de Ross). Experiência inicial.

PURPOSE: Report the initial surgical experience with four cases utilizing a pulmonary autograft for aortic valve replacement. METHODS: Four patients, all males, white, age between 23 and 46 years having aortic valve disease were submitted to aortic valve replacement with a pulmonary autograft using the root replacement technique. Right ventricular outflow tracts were reconstructed with antibiotic sterilized pulmonary or aortic homografts. All patients had control bidimensional eco-doppler (ECO) and hemodynamic study to evaluate the function of the implanted auto and homografts. RESULTS: All patients had an excellent post-operative recovery, without the necessity of inotropic drugs. All presented in normal sinus rhythm. Post-operative ECO and hemodynamic studies revealed excellent function of the implanted autografts, without gradients in three and with a 15mmHg mean residual gradient in one case. There was no regurgitation in three cases and only trace aortic insufficiency in one. The right sided homografts also showed good function, with no gradient in two cases and mean systolic gradient of 6 and 8mmHg in the other two. CONCLUSION: The pulmonary autograft procedure should be implemented definitely in our country.

Substituição da valva aórtica com auto-enxerto pulmonar (cirurgia de Ross). Experiência inicial / Aortic valve replacement with pulmonary autograft (Ross procedure). Initial experience

Objetivo - Relatar a experiência cirúrgica inicial de 4 casos com a utilizaçäo do auto-enxerto pulmonar para substituiçäo da valva aórtica. Métodos - Quatro pacientes masculinos, brancos, com idades entre 23 e 46 anos, portadoras de valvopatia aórtica, forma submetidos a substituiçäo da valva aórtica pelo auto-enxerto pulmonar pela técnica de substituiçäo total da raiz aórtica. Para a reconstituiçäo da via de saída do ventrículo direito foram utilizados homo-enxertos pulmonares e aórtico conservad em soluçäo de antibióticos. Todos tiveram controle pós-operatório com eco-doppler (ECO) e estudo hemodinâmica para a avaliaçäo da funçäo dos auto e homo-enxertos implantados. Resultados - Todos apresentaram excelentes evoluçäo pós-operatória, sem necessidade de drogas inotrópicas e em ritmo sinusal. Os resultados obtidos através do ECO e estudo hemodinâmico revelaram excelente fuçäo dos auto-enxertos implantados sem gradiente em 3 casos e gradiente médio residual de 15 mmHg em um. Näo se observou reguriaçäo aórtica em 3 casos e insuficiência leve no 4o. ano. Os homo-enxertos implantados no lado direito do coraçäo apresentaram excelentes funcäo, sem gradiente em 2 anos e gradiente médio de 6 e 8 mmHg nos outros dois. Conclusäo - A cirurgia do auto-enxerto pulmonar deve ser implantada de forma definitiva em nosso meio

Purpose - Report the initial surgical experience with four cases utilizing a pulmonary autograft for aortic valve replacement Methods - Four patients, all males, white, age between 23 and 46 years having aortic valve disease were submitted to aortic valve replacement with a pulmonary autograft using the root replacement technique. Right ventricular out flow tracts were reconstructed with antibiotic sterilized pulmonary or aortic homografts. All patients had control bidimensional eco-doppler (ECO) and hemodynamic study to evaluate the function of the implanted auto and homografts. Results - All patients had an excelent postoperative recovery, without the necessity of inotropic drugs. All presented in normal sinus rhythm. Postoperative ECO and hemodynamic studies revealed excelent function of the implanted autografts, without gradients in three and with a 15mmHg mean residual gradient in one case. There was no regurgitation in three cases and only trace aortic insufficiency in one. The right sided homografts also showed good function, with no gradient in two cases and mean systolic gradient of 6 and 8mmHg in the other two. Conclusion - The pulmonary autograft procedure should be implemented definitelly in our country