External location of the buccinator muscle to facilitate electromyographic analysis

Electromyography is frequently used to measure the activity of masticatory muscles. It requires the precise setting of the electrodes, which demands the accurate location of the muscle to be evaluated. The purpose of this study was to investigate the accuracy of an external method to locate the buccinator muscle. Fifteen human cadavers were evaluated and planes were determined on the face using anatomic landmarks. An angle (a) was obtained at the intersection of these planes on the central point of buccinator muscle and measured with a protractor. The value of the angle allows locating the central point of buccinator muscle based on anatomic landmarks on the face. Statistical analysis of the collected data indicated an angle of 90º with 95% reliability, thus proving the efficacy of the proposed method.A eletromiografia é frequentemente utilizada para mensurar a atividade dos músculos mastigatórios. Esta análise exige a colocação precisa dos eletrodos, o que requer a localização exata do músculo a ser avaliado. O objetivo do presente estudo foi investigar a acurácia de um método externo para localização do músculo bucinador. Quinze cadáveres humanos foram avaliados e planos foram determinados na face utilizando-se pontos de referência anatômicos. Um ângulo (a) foi obtido na interseção desses planos no ponto central do músculo bucinador e foi medido com um transferidor. O valor do ângulo permite localizar o ponto central do músculo bucinador baseado nos pontos de referência anatômicos da face. A análise estatística dos dados obtidos indicou um ângulo de 90º com 95% de confiabilidade, confirmando dessa forma a eficácia do método proposto.São Paulo State University Dental School of Araraquara Department of Dental Materials and ProsthodonticsSão Paulo State University Dental School of Araraquara Department of MorphologyFederal University of São Paulo Medical School of São Paulo Speech TherapistUNIFESP, Medical School of São Paulo Speech TherapistSciEL

Influence of microwave sterilization on the cutting capacity of carbide burs

OBJECTIVE: This study compared the cutting capacity of carbide burs sterilized with microwaves and traditional sterilization methods. MATERIAL AND METHODS: Sixty burs were divided into 5 groups according to the sterilization methods: dry heat (G1), autoclave (G2), microwave irradiation (G3), glutaraldehyde (G4) or control - no sterilization (G5). The burs were used to cut glass plates in a cutting machine set for twelve 2.5-min periods and, after each period, they were sterilized (except G5) following the protocol established for each group. The cutting capacity of the burs was determined by a weight-loss method. Data were analyzed statistically by Kruskal-Wallis and Dunn's test. RESULTS: The means of the cutting amount performed by each group after the 12 periods were G1 = 0.2167 ± 0.0627 g; G2 = 0.2077 ± 0.0231 g; G3 = 0.1980 ± 0.0326 g; G4 = 0.1203 ± 0.0459 g; G5 = 0.2642 ± 0.0359 g. There were statistically significant differences among the groups (

Pervasive gaps in Amazonian ecological research

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

Health-related quality of life in patients with type 1 diabetes mellitus in the different geographical regions of Brazil : data from the Brazilian Type 1 Diabetes Study Group

Background: In type 1 diabetes mellitus (T1DM) management, enhancing health-related quality of life (HRQoL) is as important as good metabolic control and prevention of secondary complications. This study aims to evaluate possible regional differences in HRQoL, demographic features and clinical characteristics of patients with T1DM in Brazil, a country of continental proportions, as well as investigate which variables could influence the HRQoL of these individuals and contribute to these regional disparities. Methods: This was a retrospective, cross-sectional, multicenter study performed by the Brazilian Type 1 Diabetes Study Group (BrazDiab1SG), by analyzing EuroQol scores from 3005 participants with T1DM, in 28 public clinics, among all geographical regions of Brazil. Data on demography, economic status, chronic complications, glycemic control and lipid profile were also collected. Results: We have found that the North-Northeast region presents a higher index in the assessment of the overall health status (EQ-VAS) compared to the Southeast (74.6 ± 30 and 70.4 ± 19, respectively; p < 0.05). In addition, North- Northeast presented a lower frequency of self-reported anxiety-depression compared to all regions of the country (North-Northeast: 1.53 ± 0.6; Southeast: 1.65 ± 0.7; South: 1.72 ± 0.7; Midwest: 1.67 ± 0.7; p < 0.05). These findings could not be entirely explained by the HbA1c levels or the other variables examined. Conclusions: Our study points to the existence of additional factors not yet evaluated that could be determinant in the HRQoL of people with T1DM and contribute to these regional disparities

Pervasive gaps in Amazonian ecological research

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

Human teeth versus bovine teeth: cutting effectiveness of diamond burs

Aim : In this study, a mass-loss method was used to verify whether bovine enamel has the same wear pattern as human enamel in cutting efficiency tests of diamond burs. Methods: Seventy-two teeth were used: 36 human molars (HT) and 36 bovine mandibular central incisors (BT). The enamel of the teeth was cut using diamond bur #1092 attached to a high-speed handpiece under controlled pressure (50-80 g). Each bur (n=12) cut for a total of 72 min, divided into 6 periods of 12 min each (12-min, 24-min, 36-min, 48-min, 60-min, and 72-min). The amount of enamel removed was determined by the difference between pre- and post-cut tooth masses. Results: The mean amounts (g) of enamel removed were: HT- 12-min=0.11; 24-min=0.12; 36-min=0.11; 48-min=0.11; 60-min=0.10; 72-min=0.12; BT- 12-min=0.12; 24-min=0.15; 36-min=0.15; 48-min=0.13; 60-min=0.16; 72-min=0.14. Data were analyzed using ANOVA followed by Tukey′s test, and the results showed statistically significant differences between human and bovine teeth (p<0.001) and among the cutting periods (p<0.001). Conclusions : It was concluded that the cutting efficiency of the burs was different between the tested substrates, and that bovine enamel underwent greater mass loss than did human enamel

Human teeth versus bovine teeth: cutting effectiviness of diamond burs

Aim: In this study, a mass-loss method was used to verify whether bovine enamel has the same wear pattern as human enamel in cutting efficiency tests of diamond burs. Methods: Seventy-two teeth were used: 36 human molars (HT) and 36 bovine mandibular central incisors (BT). The enamel of the teeth was cut using diamond bur #1092 attached to a high-speed handpiece under controlled pressure (50-80 g). Each bur (n=12) cut for a total of 72 min, divided into 6 periods of 12 min each (12-min, 24-min, 36-min, 48-min, 60-min, and 72-min). The amount of enamel removed was determined by the difference between pre- and post-cut tooth masses. Results: The mean amounts (g) of enamel removed were: HT- 12-min=0.11; 24-min=0.12; 36-min=0.11; 48-min=0.11; 60-min=0.10; 72-min=0.12; BT- 12-min=0.12; 24-min=0.15; 36-min=0.15; 48- min=0.13; 60-min=0.16; 72-min=0.14. Data were analyzed using ANOVA followed by Tukey’s test, and the results showed statistically significant differences between human and bovine teeth (p<0.001) and among the cutting periods (p<0.001).Conclusions: It was concluded that the cutting efficiency of the burs was different between the tested substrates, and that bovine enamel underwent greater mass loss than did human enamel.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Human teeth versus bovine teeth: cutting effectiveness of diamond burs

this study, a mass-loss method was used to verify whether bovine enamel has the same wear pattern as human enamel in cutting efficiency tests of diamond burs. Methods: Seventy-two teeth were used: 36 human molars (HT) and 36 bovine mandibular central incisors (BT). The enamel of the teeth was cut using diamond bur #1092 attached to a high-speed handpiece under controlled pressure (50-80 g). Each bur (n=12) cut for a total of 72 min, divided into 6 periods of 12 min each (12-min, 24-min, 36-min, 48-min, 60-min, and 72-min). The amount of enamel removed was determined by the difference between pre- and post-cut tooth masses. Results: The mean amounts (g) of enamel removed were: HT- 12-min=0.11; 24-min=0.12; 36-min=0.11; 48-min=0.11; 60-min=0.10; 72-min=0.12; BT- 12-min=0.12; 24-min=0.15; 36-min=0.15; 48-min=0.13; 60-min=0.16; 72-min=0.14. Data were analyzed using ANOVA followed by Tukeys test, and the results showed statistically significant differences between human and bovine teeth (p<0.001) and among the cutting periods (p<0.001).Conclusions: It was concluded that the cutting efficiency of the burs was different between the tested substrates, and that bovine enamel underwent greater mass loss than did human enamel