21 research outputs found

    Torque Analysis of a Triple Acid-Etched Titanium Implant Surface

    Get PDF
    The present study aimed to evaluate the removal torque of titanium implants treated with triple acid etching. Twenty-one rats were used in this study. For all animals, the tibia was prepared with a 2 mm drill, and a titanium implant (2 × 4 mm) was inserted after treatment using the subtraction method of triple acid etching. The flaps were sutured. Seven animals were killed 14, 28, and 63 days after implant installation, and the load necessary for removing the implant from the bone was evaluated by using a torque meter. The torque values were as follows: 3.3 ± 1.7 Ncm (14 days), 2.2 ± 1.3 Ncm (28 days), and 6.7 ± 1.4 Ncm (63 days). The torque value at the final healing period (63 days) was statistically significantly different from that at other time points tested (ANOVA, p=0.0002). This preliminary study revealed that treatment with triple acid etching can create a promising and efficient surface for the process of osseointegration

    Bone-Implant Contact around Crestal and Subcrestal Dental Implants Submitted to Immediate and Conventional Loading

    Get PDF
    The present study aims to evaluate the influence of apicocoronal position and immediate and conventional loading in the percentage of bone-implant contact (BIC). Thus, 36 implants were inserted in the edentulous mandible from six dogs. Three implants were installed in each hemimandible, in different positions in relation to the ridge: Bone Level (at crestal bone level), Minus 1 (one millimeter apical to crestal bone), and Minus 2 (two millimeters apical to crestal bone). In addition, each hemimandible was submitted to a loading protocol: immediate (prosthesis installed 24 hours after implantation) or conventional (prosthesis installed 120 days after implantation). Ninety days after, animals were killed, and implant and adjacent tissues were prepared for histometric analysis. BIC values from immediate loaded implants were 58.7%, 57.7%, and 51.1%, respectively, while conventional loaded implants were 61.8%, 53.8%, and 68.4%. Differences statistically significant were not observed among groups (P=0.10, ANOVA test). These findings suggest that different apicocoronal positioning and loading protocols evaluated did not interfere in the percentage of bone-implant contact, suggesting that these procedures did not jeopardize osseointegration

    Pervasive gaps in Amazonian ecological research

    Get PDF

    Pervasive gaps in Amazonian ecological research

    Get PDF
    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

    Pervasive gaps in Amazonian ecological research

    Get PDF
    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

    Pervasive gaps in Amazonian ecological research

    Get PDF
    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

    Oral conditions and body weight in children from a public school in Manaus, AM, Brazil

    No full text
    Abstract Introduction Some studies have pointed to links between the prevalence of caries and periodontal disease, and the occurrence of overweight or obesity; but, few studies have been conducted in children. Objective To assess the relationship between periodontal disease, tooth decay and body weight in children from a public school in Manaus, AM, Brazil. Material and method The study included one hundred and sixty-nine children. Records were obtained of decayed, missing and filled (DMFT) permanent teeth, and of decayed, extracted, or filled (DEF) deciduous teeth, as well as the record of the community periodontal index (CPI). The classification of body weight category was obtained in percentile using the z-Score table. Result Higher averages of weight and body mass index (BMI) were seen in the overweight and obesity groups (p<0.05). All groups were similar regarding the DMFT /DEF and CPI codes from 0 to 4 (p>0.05). All groups showed higher averages of CPI 0 in comparison with other CPI codes from 1 to 4 (p<0.05), and most of the children showed sites with probing depth <3.5 mm and without bleeding on probing. Conclusion There was no relationship between body weight and the occurrence of dental caries and periodontal disease in the studied population. Obesity and overweight showed no negative influence on the increase in the prevalence of these diseases

    Oral conditions and body weight in children from a public school in Manaus, AM, Brazil

    No full text
    Abstract Introduction Some studies have pointed to links between the prevalence of caries and periodontal disease, and the occurrence of overweight or obesity; but, few studies have been conducted in children. Objective To assess the relationship between periodontal disease, tooth decay and body weight in children from a public school in Manaus, AM, Brazil. Material and method The study included one hundred and sixty-nine children. Records were obtained of decayed, missing and filled (DMFT) permanent teeth, and of decayed, extracted, or filled (DEF) deciduous teeth, as well as the record of the community periodontal index (CPI). The classification of body weight category was obtained in percentile using the z-Score table. Result Higher averages of weight and body mass index (BMI) were seen in the overweight and obesity groups (p0.05). All groups showed higher averages of CPI 0 in comparison with other CPI codes from 1 to 4 (p<0.05), and most of the children showed sites with probing depth <3.5 mm and without bleeding on probing. Conclusion There was no relationship between body weight and the occurrence of dental caries and periodontal disease in the studied population. Obesity and overweight showed no negative influence on the increase in the prevalence of these diseases
    corecore