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

The objective of this study was to evaluate the effect of replacing, forage proportions of 2 shrub legumes by Square banana fruit (Musa ABB) on nutrient content and methane production. The experiment was carried out between January and November 2017 and a factorial design with eight treatments was used. The mixtures were stored for 50 days in bags of 5.0 kg. The increase of square banana fruit reduces the concentration of CP and dNDF, while the amount of total starch and pectins increases. Regarding the ruminal parameters, the concentration of NH4 is reduced, by a reduction in the CP concentration, although it must be analyzed how much it could have been transformed into a microbial protein. The incubation time of the sample could have generated that the fiber was not degraded and this altered the proportion of the VFA. Finally, as the amount of fruit was increased, the amount of methane produced was reduced, also Poró showed a greater reduction capacity compared to Cratylia. Silage of Square bananas and legumes can provide quality nutrients and have the ability to reduce methane production, resulting in increased productivity and lower environmental impact.

The energy content of ingredients or rations cannot be determined by using standard analytical techniques, so most laboratories provide the user with estimated energy values and the user is generally unaware of how the energy concentration of ingredients or rations is estimated. Thus, the objective of this document is to present an extract of the methodology used by the NRC (2001) model to determine the energy content in feed or rations for dairy cattle. Within the steps, it is required to calculate total digestible nutrients (TDN) in the ingredients or ration at a maintenance level (TDN1x) using the energy contribution provided by the chemical fractions of the feed (fibrous carbohydrates, non-fibrous carbohydrates, lipids and crude protein) measured or calculated from laboratory analysis and from its true digestibility, and then with the help of a series of mathematical equations calculate its energy content. Despite the fact that many years have passed since the publication of the nutritional requirements of dairy cattle, there is still a lot of unawareness on the part of technicians and students in the field of how to obtain this value, so it is intended to make this information more accessible to potential users in Costa Rica and Latin America.

Objectives: Odontogenic keratocyst (OKC) and ameloblastoma are slowly growing and locally invasive tumors with high recurrence rate. The aim of this study was to investigate the clinicopathologic features of recurrent ameloblastoma and OKC cases, and evaluate outcomes of our treatments in terms of recurrence. Material and Methods: A total of 23 patients with confirmed recurrent ameloblastoma or OKC and treated in our clinic within eleven years period were reviewed retrospectively. Results: Eleven recurrent OKC cases and twelve recurrent ameloblastoma cases were included. Most recurrences occurred within five years after the initial treatment (69.6%). Enucleation had the highest recurrence rate among the first treatments (18/23). All recurrences were located in the mandible, with one exception (22/23). All recurrent OKCs were multilocular. Different histopathologic subtypes of ameloblastoma were seen in our study, follicular ameloblastoma was the most common (8/12). The mean diameter of the lesions was 4.3 cm (ranging from 2 cm to 7 cm). Statically significant relation was found between location and diameter of lesion and year of recurrence onset (p=0.004; p=0.026). We performed radical treatments in these cases (ten patients underwent marginal resections, and thirteen patients underwent segmental resection), and no recurrence was observed during the follow-up period. Conclusion: Previous inadequate surgical procedures were the most important cause of recurrence. Marginal or segmental resection with safety margins is the best method to treat recurrences of OKC or ameloblastoma cases.

In December 2019, a novel coronavirus disease (COVID-19) presenting with pneumonia emerged in Wuhan, China. The ongoing spread of COVID-19 worldwide is creating enormous uncertainty. In particular, the dental profession is facing a major challenge. Due to the characteristics of dental settings, the risk of cross-infection is elevated between patients and dental staff. The present review aimed to briefly discuss the overview of the disease, including the basic science, epidemiology, symptoms, routes of transmission and several topics that the authors believe are binding and relevant to the dental practice. The guidelines adopted by governments and international organizations also address all dental associations to protect the health of the community and to contain the spread of COVID-19 infection until a vaccine or an effective/validated treatment becomes available.

Dental plaque-induced gingival enlargements associated with local factors such as the use of orthodontic appliances are frequently observed in young patients, with inadequate dental biofilm control. Among the recommended therapeutics to treat this condition is the Nonsurgical phase and the surgical approach. A clinical case of a 16-year-old patient with a gingival enlargement and its respective treatment is presented.

While countries are facing different stages in their COVID-19 infection rates, worldwide there are millions of students affected by universities’ facilities closures due to the pandemic. Some institutions have enforced strategies to transfer some courses to a virtual modality, but many Dental Schools have been challenged to deal with a situation which requires emergency measures to continue the academic course in the middle of lock-downs and social distancing measures. Despite the fact that the number of online academic programs available, especially graduate programs, has increased in diverse modalities, this pandemic forced e-learning processes to develop abruptly. The likelihood of using e-learning strategies in dentistry was substantiated in the scientific literature and an overview of these opportunities is presented. Additionally, the experience of the University of Costa Rica Faculty of Dentistry is presented, as it was evident that some of the key elements in a e-learning environment needed a quick enhancement and initiation of some processes was required. First, it was necessary to categorize the academic courses depending on their virtualization's possibility (curricula analysis and classification), to better understand the extent of the impact and the work needed to contain, as far as the possibilities allowed, negative consequences on students learning process. Second, teachers needed further training in the application of virtual strategies which they hadn’t used before. do Third, an evaluation of the students’ conditions and needs was conducted in a form of a survey. Finally, teachers and students activated the available virtual platforms. For many Dental Schools, this virtualization process is an ongoing progress although it was abruptly imposed, but this moment indeed represents an enormous opportunity to move forward and get immerse in the virtualization environment as a teaching/learning experience.

The change in the demographic distribution of Costa Rica establishes the elderly as a public health priority. Oral health is a multidimensional indicator, which includes biological, social, and psychological dimensions. Besides using measures of morbidity and mortality, different indicators seek to approximate other subjective dimensions. There is an increasing interest in analyzing the role of quality of life on health. This study aims to identify the main determinants of Oral Health-Related Quality of Life (OHRQL) in the elderly attending a day center in the city of Desamparados (San José, Costa Rica). This is a descriptive cross-sectional study ran between 2018 and 2019. OHRQL was measured via the General / Geriatric Oral Health Assessment Index (GOHAI). As independent variables, sociodemographic, socioeconomic, morbidity, health behaviors, and drug consumption were included. Bivariate analyzes were performed using the Wilcoxon, Kruskall-Wallis, and Spearman non-parametric tests, using STATA 14. This study revealed differences in GOHAI scores according to demographic, socioeconomic, morbidity, medication, and health behaviors. Those over 80 years old, women, with higher levels of education, high income, without edentulism, with low levels of xerostomia, people without diseases, who do not take medication, who do not smoke, play sports, do not snack and who consume moderately sugars, are those that report a better OHRQL compared to their counterparts.

ECA2 receptors have an important gene expression in the squamous cells of the tongue and salivary glands, a mechanism that is convenient for the inoculation of SARS CoV2 since it seeks to make the assembly complex through its glycoprotein or spike protein towards the ECA2 receptor of the oral mucosa. Once inoculated and favored by proteases, it is the key that allows the entry of the virion into the host cell for its subsequent replication, increase of viral load and potential deamination and infection; dental professionals must be alert to the mechanisms of infection in the oral cavity for their own protection and that of the patients who are treated by this health personnel.

Avoiding biofilm formation on dentures is associated with maintaining the surface properties of acrylic-based dentures. The aim of the study is to investigate the effects of two different cleaning agents (Corega and Klorhex 0.2% chlorhexidine gluconate) on surface roughness of the denture regarding efficacy of curing procedures. A total of sixty disc-shaped specimens were prepared with two different methods as long and short curing processes. The specimens were divided into subgroups according to the immersion solutions (distilled water, Corega tablet group and Klorhex 0.2% chlorhexidine gluconate group) (n=10). The samples were kept in a solution for 8 hours per day during a month. The average Ra1 (before exposure to the cleanser agent) and Ra2 (after exposure to the cleanser agent) of each sample was measured. A two-way ANOVA and post hoc Tukey test was used for statistical analysis. The solutions significantly increased the Ra values in both acrylic groups (p<0.001). While the effect of the distilled water group was significantly lower than Corega and Klorhex in the long-term curing group (p<0.05), no significant difference was found in the short-term curing group (p>0.05). The long-term curing time is highly effective in decreasing the surface roughness of the acrylic base material.

This prospective study aimed to assess the positional features of palatally displaced maxillary canines (PDCs), their relationship with both cephalometric and dental cast measurements and treatment duration. Pretreatment panoramic and lateral cephalometric radiographs and dental casts of 46 patients (23 patients with uni/bilateral PDC and 23 patients with Class I malocclusion) were collected. The mesial inclination of the permanent canine to the midline (α angle), the distance from the cusp tip of the permanent canine to the occlusal line (d distance), and the mesial position of the crown of the displaced canine (sector) were measured on the panoramic radiographs. SNA°, SNB°, ANB°, SN-GoGn°, SN-PP°, and PP-MP° angles and sagittal inclinations of the PDCs’ (C-PP°) were measured on cephalometric radiographs. Arch length discrepancies and transversal arch measurements were also performed. The Student’s t-test, Mann-Whitney U test and Kruskal-Wallis test were used to compare variables that were not normally distributed while ANOVA was used for the normally distributed data.  The arch widths were similar between the groups while crowding was significantly greater in the PDC group. A negative correlation was found between the α angle and vertical plane angle (SN-GoGn°). Treatment duration was positively correlated with α angle and d distance but there was no relationship with the sagittal angulation of the PDC to the palatal plane (C-PP°) and the treatment duration. Treatment duration can be expected to be longer with every increase in the angle of the PDC to the midline and distance from the occlusal plane.