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Yes / This paper reviews the recent studies on the identification and cleaning methods, as well as the consequences of oil spill. The future progression on oil spill prevention studies are also projected here.

Stetig steigende Ansprüche an ästhetisch ansprechenden festsitzenden Zahnersatz, haben zu einer enormen Entwicklung im Bereich der enossalen Implantologie geführt. Ebenso führte die Weiterentwicklung im Bereich dentaler Keramiken zu einer immer häufigeren Anwendung vollkeramischer Systeme. In der vorliegenden in-vitro-Studie wurde der Einfluss verschiedener Reinigungsmethoden auf die Haftkraft rezementierter implantatgetragener Zirkoniumdioxid-Kronengerüste untersucht. Die untersuchten Parameter waren: manuelle Entfernung der Zementreste mit Hilfe eines Heidemann Spatels, Säuberung durch Ausstrahlung der Suprakonstruktion mit Aluminiumdioxid (Korngröße: 110 μm, 2 bar, 15s Dauer), kombinierte manuelle Säuberung und Ultraschallreinigung (Isopropanolbad 99%ig). Für den Versuch wurden insgesamt 52 Probekörper mit den drei genannten Parametern, sowie eine Kontrollgruppe mit unbehandelten Zirkoniumdioxid-Käppchen je 13 Mal einem Abzugsversuch unterzogen. Zur Herstellung der Kronengerüste wurden die Titan-Abutments mit dem Cercon® eye Scanner (DeguDent, Hanau) eingescannt und die Zirkoniumdioxid-Käppchen daraufhin digital mit der CAD-Software Cercon® art modelliert und im Labor der Firma DeguDent, Hanau, gefräst. Anschließend wurden die Kronengerüste auf den Abutments mit TempBond® NE der Firma Kerr (Ratstatt, Deutschland) zementiert und in der Universalprüfmaschine Zwick Z007 (Zwick, Ulm) den Abzugsversuchen bis zur Dezementierung unterzogen. Die Auswertung der Abzüge erfolgte mit der Software „testXpert“. Die Ergebnisse zeigten, dass die Kombination aus manueller Reinigung und Ultraschallbad verglichen mit den anderen Methoden zu statistisch signifikant höheren Retentionswerten führte. Zwischen der reinen manuellen Säuberung und der Reinigung durch Ausstrahlen des Kronengerüstes zeigte sich kein klinisch relevanter und signifikanter Unterschied.

Indiana University-Purdue University Indianapolis (IUPUI) / Background and Rationale: As compared with glass-based ceramics, zirconia has gained considerable popularity in restorative dentistry due to its superior mechanical properties. Clinically, however, zirconia ceramics pose a significant challenge regarding the achievement of a reliable and durable bond to resin-based cements. Thus far, it has been established that zirconia bond to resin-based cements can be enhanced after different surface conditioning methods, such as airborne particle abrasion with aluminum oxide particles. Meanwhile, another major issue pertaining to bonding of ceramic restorations is related to its potential contamination before cementation. Briefly, after sandblasting and clinical try-in procedures, zirconia can be contaminated with saliva and/or blood. As with many metals, zirconium shows a strong affinity towards the phosphate group found in saliva and other fluids, which reacts with the zirconia surface and makes bonding very difficult. Recently, a new cleaning agent called Ivoclean® (Ivoclar-Vivadent), which is an alkaline suspension of zirconium oxide particles, has been introduced in the market to remove contamination from zirconia in an effort to improve bonding to resin cements. Objective: The purpose of this study was to evaluate the influence of saliva contamination and the effect of several cleaning methods, including Ivoclean on resin bond strength to zirconia. Materials and Methods: Eighty square-shaped specimens (ϕ = 12 mm x 12 mm x 3 mm) of yttria-stabilized full-contour zirconia (Diazir®, Ivoclar-Vivadent, Amherst, NY) were sectioned from zirconia blocks using a water-cooled diamond blade. Then, these specimens were embedded in acrylic resin, and their surfaces gradually finished with silicon carbide papers (600 grit to 1200 grit). The prepared zirconia surfaces were sandblasted with 50-μm aluminum oxide particles for 15 s, under 2.5 bars and from distance of 10 mm. After sandblasting the specimens were cleaned in an ultrasonic bath containing distilled water for 5 min and air-dried for 10s. All samples were equally divided into 4 groups (n = 20) according to the cleaning method. Airborne particle abraded specimens without contamination was served as the control group. Remaining groups were contaminated with saliva, and subjected to different cleaning protocols, namely: Ivoclean®, 70% isopropanol, and no treatment. Two resin cement buttons (Multilink – Ivoclar-Vivadent, Amherst, NY) were built over each zirconia surface and light-cured following the manufacturer recommendations. The influence of contamination and surface cleaning methods on ceramic bond durability were examined after 24 h on half of the samples in each group (n = 10, n = 20), and the other half (n = 10, n = 20) specimens will undergo 6000 thermocycles (TC) before shear bond testing in the universal testing machine. Conclusion of Expected Outcomes: The shear bond strength of resin cement to zirconia led to a significant improvement after cleaning with Ivoclean both immediately and after thermal aging.

The global transportation sector is currently shifting towards autonomous vehicles. This shift comes with challenges, such as; identifying obstacles, recognising its surroundings and acting safely based on these perceptions. To accomplish mentioned tasks, the vehicle is equipped with sensors, such as lidars and cameras. A lesser known, yet significant challenge lies in keeping these sensors clean from dirt and debris which tends to accumulate on the lens of the sensors when the vehicle is moving. This report investigates how lidar- and camera sensors can be cleaned more resource-efficient in comparison to the existing sensor cleaning systems on the market. The goal was to recommend a sensor cleaning system for the range of sensors of an autonomous heavy vehicle.The authors of the study developed and tested several cleaning methods which were evaluated among each other and existing systems, while considering a system perspective. The developed cleaning systems showed that enabling a low washer fluid consumption had a negative impact on the system’s scalability, durability, compactness and complexity, in comparison to the existing cleaning systems. When utilising a high-pressured fluid, the study found that a sweeping flat spray is more resource-efficient than a static cone spray, where the latter is being commonly used in conventional sensor cleaning systems. The concepts with a sweeping flat spray resulted in a fluid consumption 4-7 times lower than the best reference cleaning system. In the case of a lidar, when considering a system perspective, it is recommended to use two telescopic flat spray nozzles facing each other and placed in either corner of the lens. It is also recommended that the nozzles are activated one at a time and that fluid I sprayed immediately on activation and kept flowing during the entire stroke to achieve a shaving or ploughing effect on the dirt. This method of cleaning has been observed to be more resource efficient compared to the reference systems. The resource-efficiency of a sweeping flat spray exists for other lens sizes as well, such as cameras and headlamps, however the scaling effects need further investigating. Therefore, additional tests are suggested, such as stress tests to determine the long-term durability of the cleaning system. Additionally, more research is needed to understand the impact of dirt in different environments and how often the sensors need cleaning. This also includes investigating how dirty the sensors can become before losing functionality. / Den globala transportsektorn är på väg att skifta till autonoma fordon. Detta skifte medför flear utmaningar; som att göra fordonet medveten om dess omgivning, identifiera objekt och agera säkert baserat på dessa intryck. För att kunna utföra dessa uppgifter är fordonen utrustade med sensorer, såsom lidar och kameror. En mindre känd utmaning ligger i att hålla dessa sensorer rena från smuts som ansamlas på sensorernas lins när fordonet framförs. Denna rapport undersöker hur lidar- och kamerasensorer kan rengöras mer resurseffektivt i förhållande till befintliga sensorrengöringssystem på marknaden. Målet var att rekommendera ett rengöringssystem för sensorerna som krävs för autonom färd, nämligen lidar och kameror. Studien utvecklade och testade ett flertal rengöringsmetoder som utvärderades bland varandra och befintliga rengöringssystem, medan samtidigt ta hänsyn till ett systemperspektiv. De utvecklade rengöringssystemen visade att en låg vätskeförbrukning påverkade systemet negativt i aspekter som skalbarhet, hållbarhet, kompakthet och komplexitet, i jämförelse med the befintliga rengöringssystemen. Vid användning av högtrycksvatten fastställde studien att en rörlig platt stråle kan vara mer resurseffektiv än en statisk konisk stråle, där den senare är vanlig bland befintliga rengöringssystem. Koncepten med en rörlig platt stråle hade en vätskeförbrukning som var fyra till sju gånger lägre än närmaste referenssystem. Vid hänsyn till ett systemperspektiv resulterade det rekommendera rengöringssystemet i två teleskopiska munstycken placerade i motstående hörnor av linsen. En i taget utvidgar sig munstyckena samtidigt som de sprutar högtrycksvatten på linsen, därav möjliggörs en rörlig platt stråle och en resurseffektiv rengöringscykel. Att rengöra med en rörlig platt stråle anses även resurseffektiv när det gäller andra storlekar på linsen, såsom en kamera- eller strålkastarlins, däremot måste eventuella följder från skalningen undersökas i vidare arbete. Det föreslås även kompletterande tester, såsom stresstester för att kunna avgöra livslängden på systemet. Vidare, efterfrågas ytterligare undersökningar på inflytande av smuts i olika miljöer, samt hur ofta sensorerna behöver rengöras. Detta inkluderar även undersökningar kring hur smutsiga sensorerna kan bli innan de tappar funktionaliteten.

Made available in DSpace on 2014-08-20T14:30:08Z (GMT). No. of bitstreams: 1 Dissertacao_rita_regina_souza_lamas.pdf: 2792167 bytes, checksum: 98b838b5683d2fd51f71535422c7380b (MD5) Previous issue date: 2012-12-14 / Poor hygiene associated with the use of orthodontic appliances in children and adolescents may increase the occurrence of oral diseases associated to, such as caries and gingivitis, turning important the knowledge of the most effective, used and designated cleaning methods for these devices. The objectives of this study were to determine the frequency of use of removable orthodontic appliances, hygiene methods used by school children and prescribed by dentists of the city of Pelotas/RS, and evaluating variables associated with it. This study was conducted in the city of Pelotas in a sample of schoolchildren aged 13-19 years from 20 schools, 16 public and 4 private. Two questionnaires were conducted to determine some socio-demographic and behavioral characteristics associated with the use of braces and another to determine the cleaning methods indicated by dentists of the city. The questionnaire of children was performed in the schools and the dentists questionnaire was performed through telephone calls. Statistical analysis was descriptive and bivariate, through the Chi-square test, or Fisher Linear Trend, depending on the type of variable exhibitor, with a p-value <0.05 as statistically significant. The frequency of use in schools was 5.4%. Students (89.76%) and dentists (47.21%) reported brushing with toothpaste as the main method of cleaning. In conclusion, the method most widely used and recommended for acrylics hygiene appliances, prescribed by dentists and used by adolescents, was brushing with toothpaste / A higiene precária associada ao uso de aparelhos ortodônticos em crianças e adolescentes pode aumentar a ocorrência de enfermidades bucais como a cárie e doenças periodontais, tornando-se importante o conhecimento dos métodos mais efetivos, mais utilizados e indicados para higienização destes dispositivos. Os objetivos deste estudo foram: determinar a frequência de uso de aparelhos ortodônticos removíveis, os métodos de higiene utilizados por escolares e indicados por dentistas da cidade de Pelotas/RS, além de avaliar variáveis associadas com isso. Foi utilizada uma amostra de escolares de 13-19 anos, provenientes de 20 escolas, quatro privadas e 16 públicas. Foram realizados dois questionários para determinar algumas características sócio-demográficas e comportamentais associadas ao uso de aparelhos ortodônticos e outro para determinar os métodos de higiene indicados pelos cirurgiões-dentistas da cidade. O questionário dos estudantes foi realizado nas escolas e o dos dentistas através de ligações telefônicas. A análise estatística foi através de análise descritiva e através de associações com os testes: Qui-Quadrado (X2) de Pearson ou Tendência linear, conforme o tipo de variável expositora, com um valor p<0,05 como estatisticamente significativo. A frequência de uso nas escolas foi de 5,4%. Os estudantes (89,76%) e dentistas (47,21%) relataram, como método de limpeza, escovação com creme dental. Em conclusão, o método mais usado e mais recomendado para higiene de aparelhos acrílicos prescrito por dentistas e usado por adolescentes foi escovação com creme dental