RESUMO
This study investigated the influence of mechanical cycling on screwed-in and tappedin implants restored with screw-retained metallic crowns. Three implant-abutmentcrown systems were evaluated: T1 (multi abutment) and T2 (standard abutment) received tapped-in abutments and S received a screwed-in abutment. The specimens were subjected to two million cycles of 0-150 N load, at 2 Hz, 30° inclination in a dry medium, and torque evaluation. Survival and removal torque were analyzed using chisquare, ANOVA, followed by Tukey's test. Differences between installation and removal torque were determined using a T-test for dependent samples. Analyses were performed in SPSS, considering α = 0.05. All specimens survived mechanical cycling in S, 40% in T1, 80% in T2 (p=0.008). Failures occurred due to loosening of the crown screw. A significant decrease in torque (p=0.000) was found. Group T1 had the lowest removal torque (1.6 ± 0.84 N.Cm²), followed by T2 (3 ± 1.49 N.Cm²) and S (6.3 ± 1.16 N. Cm²), and a statistical difference was found between Groups T1 and S. Both types of implantabutment connections were stable and can be considered for rehabilitative treatment, but failure and removal torque were influenced by the design of prosthetic abutment. Crowns were more susceptible to becoming loose in tapped-in systems.
Assuntos
Projeto do Implante Dentário-Pivô , Implantes Dentários , Torque , Dente Suporte , Análise do Estresse Dentário , Coroas , Parafusos Ósseos , Teste de MateriaisRESUMO
Diptera (Insecta) are able to transmit approximately 200 pathogenic microorganisms to humans and animals, causing more than 65 diseases, including bovine mastitis, which constitutes a major cause of economic losses in the dairy industry. In this scenario, 217 adult specimens of Diptera were collected from nine farms and identified to the family and/or species level. Of the 11 families recorded, Muscidae was the most prevalent (152 out of 217; 70%). All Diptera specimens were subjected to microbiological culture using conventional and selective media, and isolates were then identified at the species level by mass spectrometry. In total, 275 microorganisms were identified, with a predominance of pathogens related to environmental bovine mastitis (166/275 = 60·4%), that is, Enterococcus species (70/275 = 25·4%) and Escherichia coli (49/275 = 17·8%). Nontraditional agents related to bovine mastitis (called miscellaneous) were detected in 28% (77/275), as well as microorganisms with well-known zoonotic behaviour (e.g. Bacillus cereus). This is study contributes with knowledge of diversity of microorganisms carried by Diptera in the dairy environment, including pathogens associated with environmental and contagious bovine mastitis, and agents with human relevance. To our knowledge, a three-part chromogenic selective medium used to microbial culture of milk on farms was used for the first time to identification of pathogens in Diptera.
Assuntos
Dípteros , Mastite Bovina , Bovinos , Animais , Feminino , Humanos , Mastite Bovina/epidemiologia , Mastite Bovina/microbiologia , Leite/microbiologia , Prevalência , Escherichia coli , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodosRESUMO
This study evaluated the early recovery process of the palatal wounds of dogs using bismuth subgallate. Five healthy adult male dogs underwent eight 5-mm partial-thickness punch biopsies in two paired columns on the palatal mastigatory mucosa. For the haemostasis, one side received moistened gauze pressure (test group 1), and the other received bismuth subgallate (test group 2). A description of the epithelium and connective tissue repair was made at 3, 7, 14 and 21 days. During the first days, a mass of disorganized tissue covered the connective tissue, in which there was intense chronic inflammation, and migration of epithelium cells from the edges towards the central region to close to the wound was seen. The final evaluation demonstrated well organized epithelial and connective tissues in all the samples. Epithelium thickness was measured at 0, 14 and 21 days, from images of the digitalized histological sections. In comparisons between the test groups, the bismuth subgallate group was slightly better than the saline group, but no statistically significant difference was found at 21 days. It was possible to conclude that bismuth subgallate did not interfere in the tissue repair of the palatal mastigatory mucosa in dogs.