Influence of different thermopolymerization methods on composite resin microhardness

Background: Additional heat polymerization in composite resins allows greater effective ness of microhardness, flexural strength, fracture tough ness, wear resistance, and increased color stability.Material and Methods: 150 composite resin specimens were made using a 4 mm diameter and 2 mm thick bipartite steel matrix. Five resins composed of different compositions were tested (Brilliant Everglow/Coltene, Filtek One BulkFill/3M, Filtek P60/3M, Filtek Z350XT/3M, Filtek Z250XT/3M), and for each of them three types of polyme-rization were tested: light curing only (n=50); photopolymerization + autoclave thermopolymerization (n=50) and photopolymerization + microwave thermopolymerization (n=50). Each specimen was submitted to three indenta-tions by means of the Vickers microhardness test, applying a load of 300gf, associated with the time of 15s. Data were analyzed descriptively by means of statistics, standard deviation and coefficient of variation and inferentially by the F test (ANOVA) in the comparison between groups. The margin of error used in statistical test decisions was 5%.Results: The highest vicker microhardness averages were from the Control group (light curing only) on P60 (82.16) and Z250 XT (79.61) resins. The lowest averages were all verified on Brilliant Everglow resin in all polymerization methods studied: Photopolymerization (37.32), with microwave (43.80) and autoclave (45.12), followed by Bulk Fill 3M resin, ranged from 52.23 to 59.15.Conclusions: Both autoclave and microwave thermopolymerization methods showed similar behavior on the mi-crohardness of the composites studied. Considering the resin type, there was a varied behavior compared to thermo-polymerization, which increased the microhardness values for Brilliant Everglow resins (Coltene) and Filtek One Bulkfill (3M) and decreased for Filtek P60, Filtek Z350XT and Filtek Z250XT resins

Evaluation of microhardness, sorption, solubility, and color stability of bulk fill resins : a comparative study

Due to the increasing popularity of bulk fill resins, there is a concern that their components can be leached; this is because these are inserted in a single 4-5 mm increment. This in vitro study evaluated the microhardness, sorption, solubility, and color stability of three restorative bulk fill resins, namely: Filtek Bulk Fill (FBF), Tetric N-Ceram Bulk Fill (TNC), and Opus Bulk Fill (OBF). Cylindrical samples were fabricated to be 15 mm in diameter and 1 mm thick (n = 10). For the microhardness test, three random indentations were formulated on the samples using a micro-durometer with a load of 300 gf for 15 s. Sorption and solubility were then evaluated (ISO 4049: 2009). Color stability was analyzed with a digital spectrophotometer three times (initially, after 24 h, and after 7 d) during immersion in coffee and distilled water (control). The Shapiro-Wilk test was applied to analyze normality. The Mann-Whitney and Kruskal-Wallis tests were used to compare the groups and the immersion solution, with a significance level of 5%. There were a significant difference in microhardness (p<0.001), with the FBF group showing a higher value compared to the other groups (56.38). The highest average of sorption scores was observed in the OBF group (16.9 µg / mm3), followed by FBF (16.8 µg / mm3) and TNC (11.3 µg / mm3). Solubility was lowest in the OBF group (-2.83 µg / mm3), with a significant difference (p = 0.031). There was also a significant difference after 24 h in the mean ?E score of all groups (p<0.005). After one week of immersion, the group that pigmented most was OBF (p = 0.008). The three bulk fill resins had acceptable hardness, sorption, and solubility values. However, all groups showed a high pigmentation rate after 7 d of immersion in coffee

NEOTROPICAL ALIEN MAMMALS: a data set of occurrence and abundance of alien mammals in the Neotropics

Biological invasion is one of the main threats to native biodiversity. For a species to become invasive, it must be voluntarily or involuntarily introduced by humans into a nonnative habitat. Mammals were among first taxa to be introduced worldwide for game, meat, and labor, yet the number of species introduced in the Neotropics remains unknown. In this data set, we make available occurrence and abundance data on mammal species that (1) transposed a geographical barrier and (2) were voluntarily or involuntarily introduced by humans into the Neotropics. Our data set is composed of 73,738 historical and current georeferenced records on alien mammal species of which around 96% correspond to occurrence data on 77 species belonging to eight orders and 26 families. Data cover 26 continental countries in the Neotropics, ranging from Mexico and its frontier regions (southern Florida and coastal-central Florida in the southeast United States) to Argentina, Paraguay, Chile, and Uruguay, and the 13 countries of Caribbean islands. Our data set also includes neotropical species (e.g., Callithrix sp., Myocastor coypus, Nasua nasua) considered alien in particular areas of Neotropics. The most numerous species in terms of records are from Bos sp. (n = 37,782), Sus scrofa (n = 6,730), and Canis familiaris (n = 10,084); 17 species were represented by only one record (e.g., Syncerus caffer, Cervus timorensis, Cervus unicolor, Canis latrans). Primates have the highest number of species in the data set (n = 20 species), partly because of uncertainties regarding taxonomic identification of the genera Callithrix, which includes the species Callithrix aurita, Callithrix flaviceps, Callithrix geoffroyi, Callithrix jacchus, Callithrix kuhlii, Callithrix penicillata, and their hybrids. This unique data set will be a valuable source of information on invasion risk assessments, biodiversity redistribution and conservation-related research. There are no copyright restrictions. Please cite this data paper when using the data in publications. We also request that researchers and teachers inform us on how they are using the data

NEOTROPICAL CARNIVORES: a data set on carnivore distribution in the Neotropics

Mammalian carnivores are considered a key group in maintaining ecological health and can indicate potential ecological integrity in landscapes where they occur. Carnivores also hold high conservation value and their habitat requirements can guide management and conservation plans. The order Carnivora has 84 species from 8 families in the Neotropical region: Canidae; Felidae; Mephitidae; Mustelidae; Otariidae; Phocidae; Procyonidae; and Ursidae. Herein, we include published and unpublished data on native terrestrial Neotropical carnivores (Canidae; Felidae; Mephitidae; Mustelidae; Procyonidae; and Ursidae). NEOTROPICAL CARNIVORES is a publicly available data set that includes 99,605 data entries from 35,511 unique georeferenced coordinates. Detection/non-detection and quantitative data were obtained from 1818 to 2018 by researchers, governmental agencies, non-governmental organizations, and private consultants. Data were collected using several methods including camera trapping, museum collections, roadkill, line transect, and opportunistic records. Literature (peer-reviewed and grey literature) from Portuguese, Spanish and English were incorporated in this compilation. Most of the data set consists of detection data entries (n = 79,343; 79.7%) but also includes non-detection data (n = 20,262; 20.3%). Of those, 43.3% also include count data (n = 43,151). The information available in NEOTROPICAL CARNIVORES will contribute to macroecological, ecological, and conservation questions in multiple spatio-temporal perspectives. As carnivores play key roles in trophic interactions, a better understanding of their distribution and habitat requirements are essential to establish conservation management plans and safeguard the future ecological health of Neotropical ecosystems. Our data paper, combined with other large-scale data sets, has great potential to clarify species distribution and related ecological processes within the Neotropics. There are no copyright restrictions and no restriction for using data from this data paper, as long as the data paper is cited as the source of the information used. We also request that users inform us of how they intend to use the data