Sistema Regional de Información
en línea para Revistas Científicas de América Latina,
el Caribe, España y Portugal

The aim of this study was to evaluate the surface roughness of zirconia-reinforced lithium silicate ceramics treated with three different intraoral polishing systems from the manufacturers Garrison, Ultradent and Jota. The specimens were Celtra Duo ceramics (Dentsply Sirona) modeled by CAD/CAM in a CEREC unit, and then glazed. The glazed specimens were worn out with a diamond bur to simulate an occlusal adjustment in dental restorations and then treated with the different intraoral polishing systems. Polishing procedures were performed at two intervals of 40s each. Data was statistically analyzed using Student T-tests. All three systems managed to significantly reduce the roughness of the milled surface at the end of the first polishing interval, with significant differences between the three systems. In addition, it was observed that, at the end of the second interval, two systems achieved similar surface roughness, but smoother than the third system. None of the systems managed to recover the original roughness of the glazed ceramic surface. Finally, significant differences from one interval to the next suggest that surface roughness can be further reduced by extending polishing time; however, the increase in polishing time can influence the service life of intraoral instruments and working time. Consequently, the time needed to achieve optimal smoothness in each system should be considered as a key performance aspect in future research on intraoral polishing systems.

Objective: The purpose of this study was to compare the bond strength of Bio C Sealer and MTA Fillapex calcium silicate-based cements and another AH Plus epoxy resin cement. Methodology: the sealers of the study were divided into three groups to perform vertical condensation technique in the obturation of 30 inferior premolar roots, of which 5 slices of each were sectioned, to be subjected to push-out tests by means of the universal testing machine, to record the bond strength of the sealers analyzed in megapascals (MPa). Statistical analysis was done using the one-way ANOVA and Bonferroni tests. Results: it was shown that Bio C Sealer (5.30 MPa) obtained the highest adhesion strength, followed by AH Plus (3.40 MPa) and MTA Fillapex (1.39 MPa) which got the lowest bond strength with statistically significant differences between the groups. Conclusion: Bio C Sealer has greater bond strength to root canal walls.

Altered passive eruption (EPA) is a common clinical situation in which patients show an excess of the gingiva, and it is usually accompanied by short crowns, its treatment generally involves crown lengthening that can be performed with the use of some devices that favor a safe, fast and effective execution. The purpose of this case report is to present the esthetic treatment of a patient with EPA using the Kois Dento-Facial Analyzer (Panadent®) and the Chu Aesthetic Gauges (Hu-Friedy®) for crown lengthening and esthetic restorations with lithium disilicate. This clinical case shows us that proper diagnosis and treatment planning with all possible options being addressed with the patient is essential to achieve long-lasting results and patient satisfaction.

La fenestración dental en dientes deciduos se considera una lesión ósea a nivel de las raíces de dientes temporales, entre sus  características  clínicas pueden  presentarse asintomática acompañada de la destrucción  alveolar evidente considerándose de etiología multifactorial, con una prevalencia de 20% de los dientes en dientes deciduos particularmente con mayor frecuencia se observa en la porción vestibular siendo los dientes anteriores más afectados que  los posteriores, sin embargo esta  patología se encuentra poco documentada en la literatura con escasas publicaciones. El presente artículo reporta el caso clínico de un paciente 6 años 8 meses con movilidad, pérdida de la continuidad de la mucosa bucal y destrucción de la tabla ósea vestibular a nivel de unidades dentales 8.4-8.7.

Several decades ago, the theme of the brand gained interest in the academic and business worlds. Such interest generates a field of studies that arises to answer questions such as what are brands, how are they created, how are they managed and how are they evaluated. This set of questions detonates a field of knowledge from which conceptualizations, theories and models that have been circulating since 1980 are born. The objective of this article is to identify and describe the models of creation and management of brands, based on a systematic review of the literature. We have focused on the most genuine models, that is, those whose proposal is distinguishable from the others. Part of a search in the Web of Science, SCOPUS and EBSCO databases, in which 366 articles were found that proposed, analyzed or applied brand management models. This material was refined, to arrive at a corpus made up of 17 models, among which there are theoretical and empirical proposals. The article describes these models, includes their diagrams and comments on them in light of their conceptual and methodological foundations. The results show a field of knowledge in consolidation, with notable conceptual differences, diversity of criteria and orientations in the revised models. It is concluded that in the empirical-type models a short-term approach prevails, there is a wide reservation about the methodologies used for their design and they report incomparable results, while the academic-type models, although they make an effort to validate their constructs, are still far from meeting all the scientific criteria that would be expected in products of this type.

In the development of the study, the macroeconomic determinants that affected the evolution on the default rate of mortgage loans in the Ecuadorian Social Security Bank (BIESS) during the period 2011-2021, for which, an econometric model of multivariate regression supported by principles of Ordinary Least Squares (MCO) and a correlation analysis is used, for this purpose the variation generated by the real Gross Domestic Product (GDP), unemployment rates, inflation, active and passive referential, which seek to explain the influence on the rate of non-payment (default) was used as independent variables. Concluding, that the factors that directly affect in a positive and significant way are the rates of unemployment, inflation, passive referential and e; Real GDP (change). On the contrary, the referential active rate has an inverse impact on delinquency. This research will contribute to studies carried out no social security financial institutions, because it determines the factors that influenced the delinquency of de mortgage portfolio of the BIESS, input that could be used for a sensitivity analysis of the portfolio and the calculation of the expected loss, which support future reforms in the regulations of the entities that are part of the country's social security and in the control methodologies applied by the regulatory entities.

The environment, which today is becoming increasingly volatile, uncertain, complex and ambiguous in indigenous communities, affects the development of projects that address research, cooperation, innovation and development to consolidate future enterprises that articulate the interests of the groups within the framework of their cultural, social, economic, environmental and other traditions. Based on the above, the objective of this article is to analyze indigenous entrepreneurship projects in volatile, uncertain, complex and ambiguous contexts, based on a literature review supported by published scientific articles oriented to establish the relationship between the environment and the evolution of communities. This work was carried out by consulting scientific and academic databases such as ScienceDirect, ISI - Web of Science, Springer, Scielo, Google Scholar, and Scopus, completing the process with content analysis and systematization of articles in NVivo software. Finally, several studies were found in four categories: indigenous community development projects, innovation and development, indigenous project and indigenous entrepreneurship, showing the importance of building participatory methodological proposals that lead to a reflection on the understanding of community participation, the impact of assertive communication towards social projects and the volatile, uncertain, complex and ambiguous environment as a means of interaction with the projects.

Small businesses are flexible organizations that adapt to new directions, protagonists in the local market, in Latin America they are a source of livelihood for households, contribute to tax revenues and Gross Domestic Product (GDP) growth. In times of pandemic this sector of the economy was very affected, it is worth analyzing the incidences of the restrictions established by the Ecuadorian government in the COVID context. The objective of this study was to know the incidences left by the restrictive measures in the middle of the pandemic. The descriptive exploratory method applied to the group of small businesses in the city of Quito for the years 2019 and 2020 was used. Among the results of this research are: the closure of 425 companies, decrease in employment and the impact on financial variables such as the income tax that the Internal Revenue Service failed to collect for more than 10 million dollars. The conclusions indicate that this group of companies is more vulnerable to disastrous events such as the pandemic, revealing the difficulty in covering new investments and staying in the market, as well as the lack of resources, via taxes, which also affected management operation of the public apparatus. Challenges for future research represent: the analysis of incidents in other important cities of the country and the resilience strategies adopted by businessmen in times of health emergency.

This research is justified in view of the educational inclusion of people with Intellectual Disabilities (ID) and the need to implement support and reasonable adjustments in the Educational Curriculum, so that the teaching-learning process is inclusive and equitable. The objective of the research was to know the importance of the implementation of supports and reasonable adjustments that can be included in the curriculum for the teaching of Social Sciences in students with ID. The methodology that was used is based on the inductive method, it was a qualitative approach, descriptive in scope, action-participatory design, a focus group, and interviews were applied to 3 students, 8 teachers in the area of ​​Social Sciences and 2 psychologists from the Department of Student Counseling. The most relevant result was that there is ignorance and application of supports and reasonable adjustments by some teachers, and as for those who, if they know them and apply them, these are perceived by the students and it is evidenced in the motivation and integration that presented, since they actively participated in each of the activities carried out. In conclusion, the use of supports and reasonable adjustments favors the teaching-learning process of students with intellectual disabilities, guaranteeing full inclusion, promoting autonomy and participation in society, contributing to improve the quality of life.

At present, mathematical modelling in research in educational environments has acquired a notable presence, which is, why many countries have decided to incorporate it both in their curricular documents and in their teaching practice; Ecuador is no exception and its latest curricular proposal explicitly incorporates it. Textbooks form part of the resources most used by teachers, therefore, the objective of this research is to determine the presence of mathematical modelling in the statistics and probability block through a comparative study of the textbooks delivered by the Ministry of Education in the years 2016-2019 compared to the books currently used and delivered to students from the year 2020. The methodology used responds to a quantitative approach, with a descriptive scope, 497 activities were analysed through a content analysis. The results show the scarce presence of mathematical modelling, although the current textbooks present more contextualised problems, the mathematical modelling activities have completely disappeared; it is concluded that an urgent reformulation of the textbooks is necessary in terms of statistics and probability, in which modelling activities are incorporated to a greater extent. The findings are useful for the Ecuadorian state and textbook authors to make decisions about how to maintain a coherent position between what is stated in the curricular guidelines and what is proposed to students in their teaching and learning process through textbooks.