Search

Purpose: To evaluate the effect of adding wollastonite and bioactive glass to an experimental mineral trioxide aggregate-like cement (MTA) on the dimensional stability, compressive strength, solubility, bioactivity, and marginal adaptation by scanning electron microscopy (SEM) and X-ray diffraction (XRD). Methods: Four groups were evaluated at 7, 14, and 21 days: MTA Angelus, experimental MTA-like cement (MTA Exp), BG10 (MTA Exp+10 wt% bioactive glass), and WO20 (MTA Exp+20 wt% wollastonite). To evaluate marginal adaptation, extracted teeth were endodontically obturated and root-end cavities were prepared and filled with the tested materials. Results: Cements with bioactive materials showed minimal dimensional changes. Adding wollastonite or bioactive glass to MTA Exp reduces the compressive strength but does not affect solubility. Bismite (Bi2O3), larnite (Ca2SiO4), calcite (CaCO3) and carbonated hydroxyapatite (Ca5[PO4,CO3]3[OH]) were identified in the four cements; ettringite (Ca6Al2[SO4]3[OH]12·26H2O) and bismutite ([BiO]2CO3) were only observed in MTA Exp, BG10, and WO20. Cement-dentin interfaces were not observed after 14 days on the BG10 and WO20 cement composites due to the ettringite formation. Conclusion: Acicular growing crystals typical of hydroxyapatite were found on the surfaces of all cements. An improved marginal adaptation was observed with the addition of wollastonite or bioactive glass. [ABSTRACT FROM AUTHOR]

The article focuses on narratives about the guardians of the archives of violence such as Abad Faciolince, Burgos Cantor and Gabriel Vásquez. It mentions collection process of different forms of archives of violence focusing on the problematic relationship of the writer with the original documents and to rescue the role of the personal in the establishment of contemporary memorialization practices. It also mentions archives of the violence in Colombia codify from mandates.

Copyright of Ideas y Valores is the property of Universidad Nacional de Colombia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The objective of this study was to formulate an experimental light-cured periodontal dressing containing alpha-humulene and to compare its physical, antimicrobial, and cytotoxicity properties with commercial gold standards (Barricaid® and Periobond®). Two periodontal dressing formulations were developed (a and b). The formulations were divided into 5 groups according to the alpha-humulene concentration as follows: Ea - control group, Ea1 - 1%, Ea5 - 5%, Ea10 - 10%, and Ea20 - 20%; Eb - control group, Eb1 - 1%, Eb5 - 5%, Eb10 - 10%, and Eb20 - 20%. Materials characterization was performed using the degree of conversion, cohesive strength, sorption, and solubility assays. Antimicrobial assay was performed using the modified direct contact test against E. faecalis and S. aureus. Cytotoxicity was assessed by the cell viability experiment using L929 fibroblasts. In general, the cohesive strength values of materials decreased as the alpha-humulene concentration increased. All the experimental dressings showed antimicrobial activity against both bacteria tested. Cell viability results for the Ea, Ea1, Eb, and Eb1 groups showed moderate cytotoxic effect. The formulations containing alpha-humulene showed similar behavior to the commercial references. Thus, formulations containing alpha-humulene have potential to be used as periodontal dressing. [ABSTRACT FROM AUTHOR]

To evaluate the ability of different esthetic archwires to retain oral biofilms in vitro. Seven different brands of coated orthodontic archwires were tested: two epoxy coated, two polytetrafluoroethylene coated, two rhodium coated, and one silver plus polymer coated. Conventional uncoated metallic archwires were used as controls. Streptococus mutans adherence to archwires was quantified by colony count following 24 hours of biolfilm growth, and total wire-associated biofilm was measured using a crystal violet staining assay. For both tests, two conditions were used: 0% sucrose and 3% sucrose. For statistical analysis, P <.05 was considered as statistically significant. For S. mutans colony forming units per biofilm, there were no statistically significant differences among the various archwires (P =.795 for 0% sucrose; P =.905 for 3% sucrose). Regarding total biofilm formed on archwires in the 3% sucrose condition, there were statistically significant differences in crystal violet staining only for the comparison between Niti Micro Dental White and Copper Ni-Ti wires (P <.05). The clinical use of esthetic-coated orthodontic wires may be considered to have similar risks as uncoated archwires for biofilm retention. [ABSTRACT FROM AUTHOR]

Copyright of Caderno Brasileiro de Ensino de Física is the property of Caderno Brasileiro de Ensino de Fisica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The objective of this study was to evaluate the biocompatibility and mechanical properties of two commercially available and one experimental periodontal dressing materials. The cytotoxicity of Periobond®, Barricaid® and one experimental periodontal dressing based on Exothane® 8 monomer was tested on 3T3/NIH mouse fibroblast. Genotoxicity was assessed by micronuclei formation, and cell alterations were analyzed using light microscopy. Both biological assays were performed using the eluate obtained from specimens after 24, 72, or 168 hours of incubation. Mechanical characterization was assessed through the ultimate tensile strength and the water sorption and solubility tests. The significance level of a = 0.05 was used for all statistical analyses. All the materials promoted a cell viability lower than 60% in all evaluated times. In general, the cell viability was significantly reduced after 72 and 168h of specimens' incubation. Considering the factor material, there were not statistical differences in the cell viability (p = 0.156). The genotoxicity was not statistically significant among the groups in the different periods of time (p > 0.05). Differences in the ultimate tensile strength values were not statistically significant different among the groups (p = 0.125). Periobond® showed the higher water sorption values (p < 0.001). Regarding solubility, there were no statistical differences between the groups (p = 0.098). All the periodontal dressing materials evaluated in this study exerted a cytotoxic effect against mouse fibroblasts, and their toxicity became more evident over time. Among the materials evaluated, the experimental light-cure type has shown overall similar properties to the commercial references. [ABSTRACT FROM AUTHOR]

Copyright of Cadernos de Pesquisa is the property of Fundacao Carlos Chagas and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study evaluated the effect of different adhesive protocols on the shear bond strength (SBS) of bulk-fill resin composite repaired with bulk-fill or conventional composite. Cylindrical bulk-fill resin composite specimens were prepared and allocated into groups according to the bonding strategy: no treatment, Silane+Scotch Bond Multipurpose (S+SBMP), Tetric N Bond Universal, and Single Bond Universal. Following bonding strategy, bulk-fill or conventional composite buildups were performed. After 24 h of storage in distilled water at 37°C, shear force was applied to the interface using a universal testing machine. The data were analyzed by two-way ANOVA and Tukey test (α=0.05). SBS was influenced by the bonding strategy and the composite used (p<0.001). Irrespective of the composite used, the group S+SBMP yielded the highest SBS values (p<0.001). Repair bond strength of bulk-fill composites can be improved by using a silane coupling agent followed by a hydrophobic resin. [ABSTRACT FROM AUTHOR]

Copyright of Ensayos. Historia y Teoría del Arte is the property of Instituto de Investigaciones Esteticas - Universidad Nacional de Colombia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Gaceta Médica de México is the property of Publicidad Permanyer SLU and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract Sanitary-ware manufacturing has a specific particular configuration of energy consumption from the thermal point of view. Heat requirements and temperature levels through the different sub-processes in the manufacturing sequence are distributed in such a way that a proper network of recovered heat can save up to 1/3 of the primary energy consumption of the factory. A half of the total thermal requirement is devoted to fire the ware along a tunnel kiln that exhausts ¾ of this heat through the exhausting and cooling stacks at a temperature a proper temperature level to be recovered in the rest of common thermal processes as drying or heating. On the other hand, the great water consumption to flush resin molds can be saved by a multi-effect distillation treatment fed with recovered heat. Instead of rejecting it with solved salts, a combined power plant optimally sized can be coupled to match both, electrical and thermal consumptions allowing for extra heat to distillate the flushing water. This research shows how sanitary-ware manufacturing can be re-engineered to save most of the water and 31 percentof primary energy [ABSTRACT FROM AUTHOR]

Copyright of Archivos Latinoamericanos de Nutrición is the property of Sociedad Latinoamericana de Nutricion and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Archivos Latinoamericanos de Nutrición is the property of Sociedad Latinoamericana de Nutricion and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract Over the past years, significant effort has been dedicated to synthesizing low-shrinking formulations, however, development of dental composites with low volumetric shrinkage continues to be challenging. The purpose of this study was to synthesize a bisphenol allylic derivate (BPhADAC) and evaluate its inclusion in the formulation of a photopolymerizable dental composite resin, as a BisGMA diluent. Experimental (BisGMA/ BPhADAC) and control (BisGMA/TEGDMA) photopolymerizable composites were prepared. Double bond conversion, polymerization kinetics, volumetric shrinkage, water sorption, solubility, and flexural properties were investigated. The experimental composite showed higher degree of conversion values, less volumetric shrinkage and less water sorption than the control composite (p < 0.05). In addition, flexural strength between the materials was found to be similar. The overall properties prove that the allylic monomer BPhADAC could be potentially useful in the formulation of low-shrinking dental composite resins. Graphical abstract fx1 [ABSTRACT FROM AUTHOR]

Copyright of Revista de la Academia Colombiana de Ciencias Exactas, Físicas y Naturales is the property of Academia Colombiana de Ciencias Exactas, Fisicas y Naturales and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Adequate treatment of lymph node metastases is essential for patients with head and neck squamous cell carcinoma (HNSCC). However, there is still no consensus on the optimal surgical treatment of the neck for patients with a clinically positive (cN+) neck. In this review, we analyzed current literature about the feasibility of selective neck dissection (SND) in surgically treated HNSCC patients with cN + neck using the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines. From the reviewed literature, it seems that SND is a valid option in patients with cN1 and selected cN2 neck disease (non-fixed nodes, absence of palpable metastases at level IV or V, or large volume ->3 cm-multiple lymph nodes at multiple levels). Adjuvant (chemo) radiotherapy is fundamental to achieve good control rates in pN2 cases. The use of SND instead a comprehensive neck dissection (CND) could result in reduced morbidity and better functional results. We conclude that SND could replace a CND without compromising oncologic efficacy in cN1 and cN2 cases with the above-mentioned characteristics. [ABSTRACT FROM AUTHOR]

Silanization of filler particles in a dental resin composite is achieved by the formation of Si-O-Si bonds, however, these bonds are especially vulnerable to hydrolysis because this covalent bond has a significant ionic character due to the electronegativity differences between the atoms. The objective of this study was to evaluate the use of an interpenetrated network (IPN) as alternative of silanization reaction and to assess its effect in selected properties of experimental photopolymerizable resin composites. The interpenetrate network was obtained during the photopolymerization reaction of organic matrix (BisGMA/TEGDMA) with a biobased polycarbonate. Its characterization was performed via FTIR, flexural strength, flexural modulus, depth of cure, sorption water and solubility. A resin composite formulated with non-silanized filler particles was used as control. The IPN with a biobased polycarbonate was successfully synthesized. The results showed that the IPN based resin composite had higher values of flexural strength, flexural modulus, and degree of double bond conversion than the control (p < 0.05). Polymerization shrinkage, water sorption and solubility were statistically significantly lower than the control resin (p < 0.05). Finally, this study shows there were no statistically significant differences for the biocompatibility outcomes (p > 0.05). The biobased IPN replaces the silanization reaction in resin composites, improving physical and chemical properties. Therefore, IPN with a biobased polycarbonate could be potentially useful in the formulation of dental resin composites. [Display omitted] [ABSTRACT FROM AUTHOR]

To determine the clinical performance of light-cured calcium silicate-based cement for direct or indirect pulp capping. The research question was as follows: in teeth with deep caries lesions, does the use of resin-modified calcium silicate-containing composites improve the radiological success and prevent irreversible pulpitis and pulpal necrosis compared with other pulp-capping agents? The following databases were screened until September 2021: PubMed, Web of Science, Scielo, Scopus, Embase, and The Cochrane Library. Randomized clinical trials reporting the clinical evaluation of a resin-modified calcium silicate material as an agent for pulp therapy were included. Meta-analysis was performed using the Rev Manager v5.4.1 software. The risk difference and 95% confidence interval of the dichotomous outcome (restoration failure or success) were calculated for comparison. Ten studies were considered for qualitative analysis and meta-analysis. Studies evaluating the performance of light-cured calcium silicate-based cement from 1 month to a maximum follow-up period of 36 months and comparing it with the performance of CaOH, mineral trioxide aggregate, or Biodentine were included. In the global analysis for direct pulp capping at 6-month follow-up, no statistical differences were observed between the experimental group using the light-cured calcium silicate-based cement and control group (P =.28). However, at 12-month follow-up, global analysis favored the control group (P <.001). For indirect pulp capping, at 6- and 24-month follow-ups, no statistically significant differences were observed between the experimental and control groups (P =.88; P =.21). Light-cured calcium silicate-based cement showed a limited clinical performance as a direct pulp capping agent, especially when evaluated in the long term. However, using it as an indirect pulp capping agent may be a reliable and easy-to-use option for restoring teeth with deep caries. This systematic review provides evidence that supports the use of light-cured calcium silicate-based cement as an indirect pulp capping agent. [ABSTRACT FROM AUTHOR]

Copyright of Biomédica: Revista del Instituto Nacional de Salud is the property of Instituto Nacional de Salud of Colombia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To determine through a systematic review and meta-analysis the level of knowledge about pain of nursing health professionals based on their scores on the Knowledge and Attitudes Survey Regarding Pain tool and its subdimensions in different settings. Adequate pain management is closely related to the degree of knowledge about pain of the healthcare personnel. Therefore, pedagogical programs on pain have been implemented in diverse health setting. However, several studies have found significant deficiencies in the knowledge of pain in health professionals, including nurses. Systematic review and meta-analysis. The study protocol was developed, registered and published in the international prospective register of systematic reviews (PROSPERO). Scopus, PubMed, Embase, Web of Science, Cochrane Library and Google Scholar databases were searched up to June 2021. Studies from 2010 to 2021 were included in the analysis. This study was conducted according to the Report Article for Systematic Reviews and Meta-analysis (PRISMA) guidelines and the quality evaluation was realized by the Mix Methods Appraisal Tool (MMAT). A random effects model analyzed the data, due on the heterogeneity among the studies. The I2 index and Cochran's Q test were employed to inspect the heterogeneity between the studies. For the Cochran's Q test, the P-value was set at 0.05. Eighteen studies with 7942 nurses were included in the systematic review and meta-analysis. The percentage of total pain knowledge was 52.9 % (95 % CI: 47.2–58.6). The highest and the lowest knowledge scores were for the spiritual/cultural dimension (69.9 %, 95 % CI: 63.4–76.0) and the intervention dimension (36.8 %, 95 % CI: 28.1–45.9), respectively. The score of total knowledge of the six domains in nurses in the area of oncology (58.6 %, 95 % CI: 45.3–71.2) was higher than that of nurses of the other areas. The knowledge of the nursing professionals about pain was lower that the suggested level of 80 %. Our study found that the pain knowledge is positively related to the prior pain training. Therefore, there is an urgent need to include continuing educational initiatives to improve the knowledge level about pain management in all the health personnel, including the nursing professionals. [ABSTRACT FROM AUTHOR]

Summary: Intestinal-type sinonasal adenocarcinoma represents 8% to 25% of all malignant sinonasal cancer and is etiologically related to occupational exposure to wood dust. Despite its clear etiology, the mechanisms behind the carcinogenic effects of wood dust are unclear. Because it is known that carcinogens can leave specific mutational fingerprints, we aimed to analyze the spectrum of TP53 mutations and to relate the findings to the wood dust etiology of the patients. Forty-four primary tumors were examined for TP53 mutations by direct sequencing. In addition, p53 protein expression was analyzed by immunohistochemistry using a tissue microarray consisting of 92 tumors. We report a frequency of 41% (18/44) TP53 mutations and 72% (66/92) p53 immunopositivity in intestinal-type sinonasal adenocarcinoma, significantly related to wood dust, but not to tobacco etiology. G→A transition (50%, 9/18 cases) was the most common alteration detected, almost exclusively found in nonsmokers, whereas G→T (27%, 5/18 cases) was detected in smokers only. These data point to wood dust exposure as the causal factor in the mutagenesis of TP53, possibly caused by reactive nitrogen species generated through a chronic inflammatory process. [ABSTRACT FROM AUTHOR]

This article discusses the scientific experiments related to optics undertaken by Alhazen, an Arabic scientist and philosopher who lived during the 1st and 2nd centuries. The author describes the since-named Alhazen's Problem, which sought to determine the reflection point in a convex spherical mirror where the object and observer's positions are known. He also comments on Alhazen's process of solving such a problem, which was first postulated in Book V of his treatise on optics. Alhazen's influence on mathematics and philosophy is also considered.

The article presents an analysis of the personal income tax incentives as stimuli for economic development. Particular focus is given to the entrepreneurial sector in Puerto Rico, and the influence of the tax incentive policies on it. The importance of a knowledge based economy is highlighted, which means the assessment of human capital over technology and fixed assets.

Copyright of Magis: Revista Internacional de Investigación en Educación is the property of Pontificia Universidad Javeriana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article presents an ethnographic description of the Santa Inés and Santa Fe districts in the centre of Bogotá, Colombia in terms of the relationships between legality and illegality which are linked with anxiety and risk.

Copyright of Revista Virtual Universidad Católica del Norte is the property of Revista Virtual Universidad Catolica del Norte and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of DYNA - Ingeniería e Industria is the property of Publicaciones Dyna SL and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)