WorldWideScience

Sample records for canals and waterways

  1. 33 CFR 162.40 - Inland waterway from Delaware River to Chesapeake Bay, Del. and Md. (Chesapeake and Delaware Canal).

    Science.gov (United States)

    2010-07-01

    ...., between Reedy Point, Delaware River, and Old Town Point Wharf, Elk River. (b) Speed. No vessel in the..., are required to travel at all times at a safe speed throughout the canal and its approaches so as to... Point and Welch Point. (f) Sailboats. Transiting the canal by vessels under sail is not permitted...

  2. Safety And Reduce In Pollution Issues For Inland Waterway Transportation

    Directory of Open Access Journals (Sweden)

    Van Huong Dong

    2017-04-01

    Full Text Available According to the Ministry of Transport inland water transport is one of the five modes of transport in our country play a very important role. Inland waterway transport not only plays a major role in transporting large volumes of goods and passengers but also creates millions of jobs contributing to ensuring social security and national defense and security. However there are still many inadequacies in waterway transportation such as unequal waterway traffic The phenomenon of exploitation of river resources as planned or Process technology is not as planned exploitation of sand gravel etc. are common in most rivers and canals in the country. The signaling system is not synchronized between the signal of the inland waterway management unit and the signal of the owner The handling of domestic goods transportation and inland port management is inadequate The force of the means of development is fast uneven but concentrated in some urban areas and industrial parks. Therefore the Ministry of Transport has proposed a scheme to facilitate the development of a synchronized inland waterway infrastructure linking with other modes of transport To improve the capacity of the crew and the inland waterway transport crews. To create favorable conditions for inland waterway transportation business with reasonable transportation costs Improve the quality of water transport services Ensure safety and environmental friendliness Make a distinct advantage over other modes of transport. Specifically will develop promulgate mechanisms The policy is to facilitate the development of inland waterway infrastructure Build and promulgate mechanism The policy of supporting the development of the fleet has a reasonable structure with a fleet of about 30 self-propelled ships accounting for about 70 of the total number of inland waterway vessels To prioritize the development of the container fleet Inland waterway transportation and training retraining of human resources for

  3. 75 FR 32275 - Regulated Navigation Area; Gulf Intracoastal Waterway, Inner Harbor Navigation Canal, Harvey...

    Science.gov (United States)

    2010-06-08

    ... required by paragraph (d)(2) of this section, to the COTP within five days of the oral request. (4) The... be evacuated from the Harvey Canal. The Coast Guard understands that the Harvey and Algiers Canals...

  4. 33 CFR 162.65 - All waterways tributary to the Atlantic Ocean south of Chesapeake Bay and all waterways tributary...

    Science.gov (United States)

    2010-07-01

    ... Atlantic Ocean south of Chesapeake Bay and all waterways tributary to the Gulf of Mexico east and south of... All waterways tributary to the Atlantic Ocean south of Chesapeake Bay and all waterways tributary to..., which are tributary to or connected by other waterways with the Atlantic Ocean south of Chesapeake Bay...

  5. A regional waterway management system for balancing recreational boating and resource protection.

    Science.gov (United States)

    Swett, Robert A; Listowski, Charles; Fry, Douglas; Boutelle, Stephen; Fann, David

    2009-06-01

    Florida's coasts have been transformed over the past three decades as population growth and unprecedented demand for individual shore access to bays and estuaries led to the creation of residential canal developments. Thousands of miles of channels and basins were dredged as a by-product of this urbanization process. The navigable waterways that resulted are now being stressed by increasing boat traffic and canal-side activities. Recognizing their common goal to preserve the recreational and ecological value of southwest Florida waterways, the Florida Department of Environmental Protection, the four-county West Coast Inland Navigation District, and the University of Florida Sea Grant College Program signed a Memorandum of Agreement. The signatories agreed to develop a science-based Regional Waterway Management System (RWMS), which is a new approach to waterway planning and permitting based on carefully mapped channel depths, a census of actual boat populations, and the spatial extent of natural resources. The RWMS provides a comprehensive, regional overview of channel conditions and the geographic distribution and severity of existing impediments to safe navigation and resource protection. RWMS information and analyses result in regional-scale permitting to accommodate water-dependent uses while minimizing environmental impacts and reducing public expenditures. Compared with traditional approaches to waterway management, the science-based RWMS is relatively unbiased, objective, transparent, ecologically sound, and fiscally prudent.

  6. 33 CFR 162.125 - Sturgeon Bay and the Sturgeon Bay Ship Canal, Wisc.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Sturgeon Bay and the Sturgeon Bay Ship Canal, Wisc. 162.125 Section 162.125 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY INLAND WATERWAYS NAVIGATION REGULATIONS § 162.125 Sturgeon Bay and the Sturgeon Bay Ship...

  7. Governance of large infrastructures. The cases of the canals of King Willem I, the Suez Canal and the Rhine-Main-Danube waterway : an application of new institutional economics

    NARCIS (Netherlands)

    Weijnen, Thomas Jozeph Gerardus

    2010-01-01

    The starting point for this thesis is that the institutional and governances structures in which a large infrastructure project is realised, is of importance for the final result. Efficient arrangements could save substantially on total investments in infrastructures. To study in this thesis the

  8. Model-Based Design and Formal Verification Processes for Automated Waterway System Operations

    Directory of Open Access Journals (Sweden)

    Leonard Petnga

    2016-06-01

    Full Text Available Waterway and canal systems are particularly cost effective in the transport of bulk and containerized goods to support global trade. Yet, despite these benefits, they are among the most under-appreciated forms of transportation engineering systems. Looking ahead, the long-term view is not rosy. Failures, delays, incidents and accidents in aging waterway systems are doing little to attract the technical and economic assistance required for modernization and sustainability. In a step toward overcoming these challenges, this paper argues that programs for waterway and canal modernization and sustainability can benefit significantly from system thinking, supported by systems engineering techniques. We propose a multi-level multi-stage methodology for the model-based design, simulation and formal verification of automated waterway system operations. At the front-end of development, semi-formal modeling techniques are employed for the representation of project goals and scenarios, requirements and high-level models of behavior and structure. To assure the accuracy of engineering predictions and the correctness of operations, formal modeling techniques are used for the performance assessment and the formal verification of the correctness of functionality. The essential features of this methodology are highlighted in a case study examination of ship and lock-system behaviors in a two-stage lock system.

  9. Waterway Shielding System and Method

    Science.gov (United States)

    2003-04-30

    In early October 12 2002, A French VLCC (Very Large Crude Carrier) chartered by 13 Malaysian state oil company Petronas was attacked by terrorist 14...Combiner 72 may provide a 11 processor with algorithms that are used to add candidates when 12 uncertain and delete candidates when analysis data is fairly...commercial interests that normally have a need to know where 18 shipments of interest on any particular ship are presently 19 located, where competitor

  10. Cyanobacteria of the 2016 Lake Okeechobee and Okeechobee Waterway harmful algal bloom

    Science.gov (United States)

    Rosen, Barry H.; Davis, Timothy W.; Gobler, Christopher J.; Kramer, Benjamin J.; Loftin, Keith A.

    2017-05-31

    The Lake Okeechobee and the Okeechobee Waterway (Lake Okeechobee, the St. Lucie Canal and River, and the Caloosahatchee River) experienced an extensive harmful algal bloom within Lake Okeechobee, the St. Lucie Canal and River and the Caloosahatchee River in 2016. In addition to the very visible bloom of the cyanobacterium Microcystis aeruginosa, several other cyanobacteria were present. These other species were less conspicuous; however, they have the potential to produce a variety of cyanotoxins, including anatoxins, cylindrospermopsins, and saxitoxins, in addition to the microcystins commonly associated with Microcystis. Some of these species were found before, during, and 2 weeks after the large Microcystis bloom and could provide a better understanding of bloom dynamics and succession. This report provides photographic documentation and taxonomic assessment of the cyanobacteria present from Lake Okeechobee and the Caloosahatchee River and St. Lucie Canal, with samples collected June 1st from the Caloosahatchee River and Lake Okeechobee and in July from the St. Lucie Canal. The majority of the images were of live organisms, allowing their natural complement of pigmentation to be captured. The report provides a digital image-based taxonomic record of the Lake Okeechobee and the Okeechobee Waterway microscopic flora. It is anticipated that these images will facilitate current and future studies on this system, such as understanding the timing of cyanobacteria blooms and their potential toxin production.

  11. Inland Waterway Mile Markers

    Data.gov (United States)

    Department of Homeland Security — Contains 11,201 sequential mile positions of navigable inland waterways and the Gulf Intracoastal Waterway. Records include eight fields; id, latitude, longitude,...

  12. Margins of the law pertaining to water supplies and waterways

    International Nuclear Information System (INIS)

    Bickel, C.

    1981-01-01

    The author examines legal questions coming from points of contact of the law pertaining to water supplies and waterways on the one hand with the Waste Management Law, the Atomic Energy Law and Criminal Law on the other hand. He tries to find ways for solving the practical problems which arise with the execution of the law pertaining to water supplies and waterways. (HSCH) [de

  13. Hydrology of and Current Monitoring Issues for the Chicago Area Waterway System, Northeastern Illinois

    Science.gov (United States)

    Duncker, James J.; Johnson, Kevin K.

    2015-10-28

    The Chicago Area Waterway System (CAWS) consists of a combination of natural and manmade channels that form an interconnected navigable waterway of approximately 90-plus miles in the metropolitan Chicago area of northeastern Illinois. The CAWS serves the area as the primary drainage feature, a waterway transportation corridor, and recreational waterbody. The CAWS was constructed by the Metropolitan Water Reclamation District of Greater Chicago (MWRDGC). Completion of the Chicago Sanitary and Ship Canal (initial portion of the CAWS) in 1900 breached a low drainage divide and resulted in a diversion of water from the Lake Michigan Basin. A U.S. Supreme Court decree (Consent Decree 388 U.S. 426 [1967] Modified 449 U.S. 48 [1980]) limits the annual diversion from Lake Michigan. While the State of Illinois is responsible for the diversion, the MWRDGC regulates and maintains water level and water quality within the CAWS by using several waterway control structures. The operation and control of water levels in the CAWS results in a very complex hydraulic setting characterized by highly unsteady flows. The complexity leads to unique gaging requirements and monitoring issues. This report provides a general discussion of the complex hydraulic setting within the CAWS and quantifies this information with examples of data collected at a range of flow conditions from U.S. Geological Survey streamflow gaging stations and other locations within the CAWS. Monitoring to address longstanding issues of waterway operation, as well as current (2014) emerging issues such as wastewater disinfection and the threat from aquatic invasive species, is included in the discussion.

  14. Andean waterways

    DEFF Research Database (Denmark)

    Rasmussen, Mattias Borg

    , social, and cultural concerns. Set in the highland town of Recuay in Ancash, the book traces the ways in which water affects political and ecological relations as glaciers recede. By looking at the shared waterways of four villages located in the foothills of Cordillera Blanca, it addresses pertinent......Andean Waterways explores the politics of natural resource use in the Peruvian Andes in the context of climate change and neoliberal expansion. It does so through careful ethnographic analysis of the constitution of waterways, illustrating how water becomes entangled in a variety of political...... questions concerning water governance and rural lives....

  15. Andean waterways

    DEFF Research Database (Denmark)

    Rasmussen, Mattias Borg

    Andean Waterways explores the politics of natural resource use in the Peruvian Andes in the context of climate change and neoliberal expansion. It does so through careful ethnographic analysis of the constitution of waterways, illustrating how water becomes entangled in a variety of political......, social, and cultural concerns. Set in the highland town of Recuay in Ancash, the book traces the ways in which water affects political and ecological relations as glaciers recede. By looking at the shared waterways of four villages located in the foothills of Cordillera Blanca, it addresses pertinent...

  16. Tritium sample analyses in the Savannah River and associated waterways following the K-reactor release of December 1991

    International Nuclear Information System (INIS)

    Beals, D.M.; Dunn, D.L.; Hall, G.; Kantelo, M.V.

    1992-01-01

    An unplanned release of tritiated water occurred at K reactor on SRS between 22-December and 25-December 1991. This water moved down through the effluent canal, Pen Branch, Steel Creek and finally to the Savannah River. Samples were collected in the Savannah River and associated waterways over a period of a month. The Environmental Technology Section (ETS) of the Savannah River Laboratory performed liquid scintillation analyses to monitor the passage of the tritiated water from SRS to the Atlantic Ocean

  17. Do We Need to Rethink Our Waterways? Values of Ageing Waterways in Current and Future Society

    NARCIS (Netherlands)

    Hijdra, Arjan; Arts, Jos; Woltjer, Johan

    In the past canals were developed, and some rivers were heavily altered, driven by the need for good transportation infrastructure. Major investments were made in navigation locks, weirs and artificial embankments, and many of these assets are now reaching the end of their technical lifetime. Since

  18. 78 FR 34293 - Regulated Navigation Area; Gulf Intracoastal Waterway, Inner Harbor Navigation Canal, New Orleans...

    Science.gov (United States)

    2013-06-07

    ... this SNPRM, the Coast Guard considered including forecast wind and minimum standing water levels within... gates closed and pump stations functioning. However, at the request of the Coast Guard, USACE supplied... that the mooring arrangements are able to withstand winds of up to 140 mph, a water level of eleven...

  19. Osmolarity and root canal antiseptics.

    Science.gov (United States)

    Rossi-Fedele, G; Guastalli, A R

    2014-04-01

    Antiseptics used in endodontics for disinfection purposes include root canal dressings and irrigants. Osmotic shock is known to cause the alteration of microbial cell viability and might have a role in the mechanism of action of root canal antiseptics. The aim of this review was to determine the role of osmolarity on the performance of antiseptics in root canal treatment. A literature search using the Medline electronic database was conducted up to 30 May 2013 using the following search terms and combinations: 'osmolarity AND root canal or endodontic or antiseptic or irrigation or irrigant or medication or dressing or biofilm; osmolality AND root canal or endodontic or antiseptic or irrigation or irrigant or medication or dressing or biofilm; osmotic AND root canal or endodontic or antiseptic or irrigation or irrigant or medication or dressing or biofilm; osmosis AND root canal or endodontic or antiseptic or irrigation or irrigant or medication or dressing or biofilm; sodium chloride AND root canal or endodontic or antiseptic or irrigation or irrigant or medication or dressing or biofilm'. Publications were included if the effects of osmolarity on the clinical performance of antiseptics in root canal treatment were stated, if preparations with different osmolarities values were compared and if they were published in English. A hand search of articles published online, 'in press' and 'early view', and in the reference list of the included papers was carried out following the same criteria. A total of 3274 publications were identified using the database, and three were included in the review. The evidence available in endodontics suggests a possible role for hyperosmotic root canal medicaments as disinfectants, and that there is no influence of osmolarity on the tissue dissolution capacity of sodium hypochlorite. There are insufficient data to obtain a sound conclusion regarding the role of hypo-osmosis in root canal disinfection, or osmosis in any further desirable

  20. 33 CFR 165.T09-1080 - Safety Zone and Regulated Navigation Area, Chicago Sanitary and Ship Canal, Romeoville, IL.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Safety Zone and Regulated Navigation Area, Chicago Sanitary and Ship Canal, Romeoville, IL. 165.T09-1080 Section 165.T09-1080 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY REGULATED NAVIGATION AREAS AND LIMITED...

  1. Forstering cooperation in inland waterway networks : a gaming and simulation approach (chapter 23)

    NARCIS (Netherlands)

    Veenstra, A.W.; Meijeren, van J.; Harmsen, J.M.A.; Verbraeck, A.; Negenborn, R.R.; Ocampa-Martinez, C.

    2015-01-01

    Inland waterway transport is an important economic activity in the Netherlands and in Europe. Especially in the hinterland transport of containers, inland shipping is expected to form the backbone of a multimodal transport system. To support and strengthen the inland waterway industry in the

  2. Recreation value of a waterway and changes in this value

    International Nuclear Information System (INIS)

    Aittoniemi, P.

    1991-01-01

    The uniquely rich hydrological and archipelagic nature of Finland creates versatile opportunities for spending of leisure time. As various uses of waterways compete with each other, it is difficult to compare advantages and disadvantages of operations in view of various interests. This is why efforts have been made to develop methods to make the effect commensurable. Usability of shores is one important factor in the assessment of recreation use of waterways. When influence of water level changes in usability of shores is estimated, shore and bottom slope and quality, and uses and user numbers of the shores must be known. In several assessment methods, usability of shore is depicted by distance of the shifted shoreline (due to the changed water level) from the 'good' status. The studies on changes in the recreation value or usability of shores should be started by making efforts to classify and estimate various effects separately. If the value is wished to be given as one figure, the calculation basis applied, the weights and the used value functions must be stated clearly with the results. It is equally important to make a sensitivity analysis, i.e. to study effects of changes in uncertain input data on the results

  3. State Lands by Administrator - Trails and Waterways

    Data.gov (United States)

    Minnesota Department of Natural Resources — DNR land ownership and administrative interest mapped to the PLS forty level. This layer merges the DNR Control Point Generated PLS layer with IBM mainframe-based...

  4. Feasability study for waterway infrastructure: International overview and methodological recommendations

    Energy Technology Data Exchange (ETDEWEB)

    Santos Fontes Pereira, L. dos; Brandão, R.; Yamashita, Y.; Guilherme de Aragão, J.J.

    2016-07-01

    The context in which the waterway transportation is in Brazil makes clear the development need of specific methodologies for the sector planning. This paper aims to compare the methods of analysis of technical, economic and environmental viability, adopted in Europe, United States and Brazil, listing the best practices and possible improvements of the method adopted in Brazil. The analysis of the documents was based on comparative method, seeking the common elements from its attributes. Each document was analysed in terms of: its structure; type of impacts; required indicators on each impact analysis; reference values for classification of indicators; and the form of integrated analysis of different impacts. The study suggests the inclusion of certain changes in the methodology of calculation and in its combination of tools and parameters used in the measurement of fiscal impacts on the comparative analysis of standard models usually adopted in the United States, Europe and the World Bank. (Author)

  5. PROPOSED GUIDELINES ON DEVELOPING THE OPTIMISATION MODEL FOR PASSAGE PLANNING IN INLAND WATERWAYS NAVIGATION

    OpenAIRE

    Ivančić, Paško; Kasum, Joško; Pavić, Ivica

    2013-01-01

    Road transport networks are overloaded by the increasing number of vehicles [1]. This has resulted in the redirection and the increasing intensity of navigation on rivers, canals and lakes. Transportation by inland waterways of the European Union (EU) represents a reliable, economical and environmentally friendly mode of transport. The latter has been recognized as a key form of transport in the European intermodal transport system. Inland waterways as part of the transport system play an imp...

  6. A Multi-Agent System for Tracking the Intent of Surface Contacts in Ports and Waterways

    National Research Council Canada - National Science Library

    Tan, Kok S

    2005-01-01

    ...) and employ them to identify asymmetric maritime threats in port and waterways. Each surface track is monitored by a compound multi-agent system that comprise of the several intent models, each containing a nested multi-agent system...

  7. Effect of climate change on crop production patterns with implications to transport flows and inland waterways.

    Science.gov (United States)

    2011-12-01

    This project analyzed the demand for transportation capacity and changes in transportation flows on : inland waterways due to shifts in crop production patterns induced by climate change. Shifts in the crop : production mix have been observed in rece...

  8. COMPARISON OF MULTI-SCALE DIGITAL ELEVATION MODELS FOR DEFINING WATERWAYS AND CATCHMENTS OVER LARGE AREAS

    Directory of Open Access Journals (Sweden)

    B. Harris

    2012-07-01

    Full Text Available Digital Elevation Models (DEMs allow for the efficient and consistent creation of waterways and catchment boundaries over large areas. Studies of waterway delineation from DEMs are usually undertaken over small or single catchment areas due to the nature of the problems being investigated. Improvements in Geographic Information Systems (GIS techniques, software, hardware and data allow for analysis of larger data sets and also facilitate a consistent tool for the creation and analysis of waterways over extensive areas. However, rarely are they developed over large regional areas because of the lack of available raw data sets and the amount of work required to create the underlying DEMs. This paper examines definition of waterways and catchments over an area of approximately 25,000 km2 to establish the optimal DEM scale required for waterway delineation over large regional projects. The comparative study analysed multi-scale DEMs over two test areas (Wivenhoe catchment, 543 km2 and a detailed 13 km2 within the Wivenhoe catchment including various data types, scales, quality, and variable catchment input parameters. Historic and available DEM data was compared to high resolution Lidar based DEMs to assess variations in the formation of stream networks. The results identified that, particularly in areas of high elevation change, DEMs at 20 m cell size created from broad scale 1:25,000 data (combined with more detailed data or manual delineation in flat areas are adequate for the creation of waterways and catchments at a regional scale.

  9. Comparison of Multi-Scale Digital Elevation Models for Defining Waterways and Catchments Over Large Areas

    Science.gov (United States)

    Harris, B.; McDougall, K.; Barry, M.

    2012-07-01

    Digital Elevation Models (DEMs) allow for the efficient and consistent creation of waterways and catchment boundaries over large areas. Studies of waterway delineation from DEMs are usually undertaken over small or single catchment areas due to the nature of the problems being investigated. Improvements in Geographic Information Systems (GIS) techniques, software, hardware and data allow for analysis of larger data sets and also facilitate a consistent tool for the creation and analysis of waterways over extensive areas. However, rarely are they developed over large regional areas because of the lack of available raw data sets and the amount of work required to create the underlying DEMs. This paper examines definition of waterways and catchments over an area of approximately 25,000 km2 to establish the optimal DEM scale required for waterway delineation over large regional projects. The comparative study analysed multi-scale DEMs over two test areas (Wivenhoe catchment, 543 km2 and a detailed 13 km2 within the Wivenhoe catchment) including various data types, scales, quality, and variable catchment input parameters. Historic and available DEM data was compared to high resolution Lidar based DEMs to assess variations in the formation of stream networks. The results identified that, particularly in areas of high elevation change, DEMs at 20 m cell size created from broad scale 1:25,000 data (combined with more detailed data or manual delineation in flat areas) are adequate for the creation of waterways and catchments at a regional scale.

  10. Evolution of canals system linking the Vistula, Dnieper and Neman basins

    Science.gov (United States)

    Brykala, Dariusz; Badziai, Vitali

    2014-05-01

    The aim of this study is to reconstruct landscape changes in the Polesie Region - one of the largest European swampy areas (Belarus), as a result of the creation and operation of a network of canals. From the 16th century efforts were undertaken to connect the Polish areas located in the drainage basins of the Black Sea and Baltic Sea with canals. Already in 1631 the Polish Sejm (parliament) approved the project to build a canal linking the River Berezina (Dnieper basin) with the River Neris (Neman basin). However, the complicated political and economic situation of the country did not allow doing this. Only in the second half of the 18th c. hetman Ogiński financed the construction of a canal linking the Dnieper and Neman basins. The canal connecting the River Szczara (Neman basin) with the River Jasiołda (Pripyat basin) was named after its creator - the Ogiński Canal. At the same time the construction of the Królewski (Royal) Canal linking the River Muchavets (Vistula basin) and the River Pina (Pripyat basin) was under way. The construction of the canal was completed in 1783. The winding channels of the Pina and Muchavets were straightened, and the numerous canals feeding the waterway system drained vast area of marshes and wetlands of the Polesia Region. The last element that connects the catchments of the Vistula and Neman is the Augustów Canal built in the years 1825-1839 (linking the catchments of the Biebrza and Neman). Numerous changes in political boundaries in the watershed area between the Black Sea and the Baltic Sea drainage basins caused the destruction of the hydraulic structures. All the analysed canals were completely destroyed during the two world wars. In the last 200 years the amount and type of locks and weirs has changed. For example, there were no weirs on the Royal Canal in the late 18th c., in the middle of the 19th c. there were 22 such structures, while now that number has gone down to 10. All canals were created for economic reasons

  11. Relationships Between Perceived Coastal Waterway Condition and Social Aspects of Quality of Life

    Directory of Open Access Journals (Sweden)

    Melanie E. Cox

    2006-06-01

    Full Text Available Previous research has shown that the presence of natural areas is beneficial to human well-being. However, to date there have been few published studies of the effects that the condition of natural areas have on well-being. We hypothesize that coastal waterways that are perceived to be in better condition are visited more often by local residents, and as a result, residents will develop a stronger sense of place and stronger social relations with other residents, which will in turn lead to a higher quality of life. A survey was conducted to test this hypothesis in two coastal regions in Queensland, Australia. A weak relationship was found between perceived coastal quality and the number of recreational visits. In both study areas, frequency of visits to coastal waterways was significantly related to quality of life through an increased sense of place and social contacts. In the Douglas region, sense of place and social capital were closely related, and social capital was also related to quality of life. In both study areas, residents were most likely to visit waterways that were located in close proximity to their residence, suggesting that management of all waterways is essential for human well-being, and that benefits to humans will result from rehabilitating degraded waterways.

  12. Position paper: Inland waterways classification for South America : Core concepts and initial proposals

    NARCIS (Netherlands)

    Jaimurzina, A.; Koedijk, O.C.; Wilmsmeier, G.; Dohms, A.; Montiel, D.; Pauli, G.; Rigo, P; Spengler, T.; Wens, F.

    2016-01-01

    South America, as of yet, has not been able to take full advantage of its extensive system of naturally navigable waterways and in making them an integrated part of the region’s transport network to cater for the ever increasing demand for cargo and human mobility. Infrastructure limitations are one

  13. 78 FR 75359 - Waterway Suitability Assessment for Construction and Operation of Liquefied Gas Terminals; Orange...

    Science.gov (United States)

    2013-12-11

    ... Assessment for Construction and Operation of Liquefied Gas Terminals; Orange, TX AGENCY: Coast Guard, DHS... waterfront facility handling and storing Liquefied Hazardous Gas (LHG) at its Orange, Texas facility. The... LHG marine traffic in the associated waterway. INVISTA, S.a.r.l. located in Orange, Texas submitted an...

  14. Socio-cultural impacts of construction and regulation of the waterway of Oulujoki river

    International Nuclear Information System (INIS)

    Ruotsala, H.

    1992-01-01

    The purpose of study was to clarify the socio-cultural impacts of the regulation and construction of Oulujoki river on the everyday life of people. Changes in work and livelihood, living and living satisfaction, and leisure time and recreation are considered as variables. Quantitative and qualitative methods were combined in the study. The principal study material is composed of answers to a questionnaire and of 109 thematic interviews on the topic. The hold of the study is phenomenological-hermeneutical, with the intention to interpret the matter from the viewpoint of the attitudes and requirements of the waterway users. The theoretical frame of reference was culture-ecological point of view and adaptive process. The emphasis of the study is on sociocultural adaptation. The attitude towards waterway construction and regulation was dependent on the background of the person interviewed. The attitude was considered e.g. by various interest groups and professional groups, such as farmers, inhabitants on the shore, recreation users, fishermen, municipal elected officials. Other important variables were age, family stage and sex. Big local differences in the attitudes could also be found. While prevailing values in society and peoples' modes of living are changing, also the attitude towards waterway and changes caused by waterway construction has changed in the region studied. The impacts on the sources of livelihood are minor for the moment, the impacts on living satisfaction and recreations are significant. While leisure time is increasing the recreation value of waterway increases, too. At the construction stage of the river, the economical and productional advantages took priority, and then no attention was paid to recreational use

  15. Assessment of periapical health, quality of root canal filling, and ...

    African Journals Online (AJOL)

    Sixty three teeth were found to have short root canal fillings, whereas 74 teeth had adequate root canal fillings, and the remaining 10 teeth had over extended root canal filling. A significant correlation was observed between the length of root filling and apical periodontitis (P = 0,023). Inadequately dense root canal filling was ...

  16. 33 CFR 207.100 - Inland waterway from Delaware River to Chesapeake Bay, Del. and Md. (Chesapeake and Delaware...

    Science.gov (United States)

    2010-07-01

    ... enter or pass through any part of the waterway will be contingent on the vessel's having adequate... facilities are of limited capacity, and permission to occupy them for periods exceeding 24 hours must be...

  17. Marine Radioactivity Studies in the Suez Canal, Part I: Hydrodynamics and Transit Times

    Science.gov (United States)

    Abril, J. M.; Abdel-Aal, M. M.

    2000-04-01

    This paper describes work carried out under the IAEA Project EGY/07/002 to study the dispersion of radioactive material in the Suez Canal. This effort is linked with the increased public concern about radiation safety through this important trade route. To follow the fate of radioactive wastes along this waterway, we had to solve the hydrodynamics of the water, governed mainly by tides, atmospheric forcing and the drift currents produced by horizontal salinity gradients and by differences in mean sea level (MSL) at the two entrances of the Canal. The hydrodynamics has been studied using both 1-D and 2-D modelling approaches, and a reasonable calibration has been possible from the data set prepared with the collaboration of the Suez Canal Authority. Dispersion of conservative pollutants has been preliminarily studied by using a 1-D-Gaussian approach. Thus, we are computing the path of the plumes and the time evolution of concentrations for different scenarios of discharges and under different seasonal conditions. The transit times can vary enormously during the year, ranging from a few days to several months, depending on the differences in MSL at the two entrances of the Canal.

  18. Root canal treatment and special needs patients.

    Science.gov (United States)

    Yap, E; Parashos, P; Borromeo, G L

    2015-04-01

    To identify current trends of root canal treatment for patients with special needs. A postal questionnaire was sent to General Dentists in Victoria, Australia and Endodontists and Special Needs Dentists across Australia to determine the extent of root canal treatment performed on special needs patients. Over a four-month period, 1120 questionnaires were distributed with an overall response rate of 63.9% (n = 716). Response rates were 63.2% (n = 655), 68.5% (n = 50) and 100.0% (n = 11) amongst General Dentists, Endodontists and Special Needs Dentists, respectively. Endodontists (95.7%) and Special Needs Dentists (100.0%) performed significantly more root canal treatment on adult patients with special needs compared with 51.2% of General Dentists, (P special needs patients compared with only 29.7% of General Dentists (P special needs patients was more likely to be carried out by specialist dental practitioners who were more likely to utilize a pharmacological approach for behaviour guidance and to perform single-visit root canal treatment compared with General Dentists. A multidisciplinary approach for special needs patients who require root canal treatment provides an opportunity for these patients to retain their dentition. © 2014 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  19. Otolith and canal reflexes in human standing

    Science.gov (United States)

    Cathers, Ian; Day, Brian L; Fitzpatrick, Richard C

    2005-01-01

    We used galvanic vestibular stimulation (GVS) to identify human balance reflexes of the semicircular canals and otolith organs. The experiment used a model of vestibular signals arising from GVS modulation of the net signal from vestibular afferents. With the head upright, the model predicts that the GVS-evoked canal signal indicates lateral head rotation while the otolith signal indicates lateral tilt or acceleration. Both signify body sway transverse to the head. With the head bent forward, the model predicts that the canal signal indicates body spin about a vertical axis but the otolith signal still signifies lateral body motion. Thus, we compared electromyograms (EMG) in the leg muscles and body sway evoked by GVS when subjects stood with the head upright or bent forward. With the head upright, GVS evoked a large sway in the direction of the anodal electrode. This response was abolished with the head bent forward leaving only small, oppositely directed, transient responses at the start and end of the stimulus. With the head upright, GVS evoked short-latency (60–70 ms), followed by medium-latency (120 ms) EMG responses, of opposite polarity. Bending the head forward abolished the medium-latency but preserved the short-latency response. This is compatible with GVS evoking separate otolithic and canal reflexes, indicating that balance is controlled by independent canal and otolith reflexes, probably through different pathways. We propose that the short-latency reflex and small transient sway are driven by the otolith organs and the medium-latency response and the large sway are driven by the semicircular canals. PMID:15618274

  20. Incidence and characteristics of mandibular accessory canals: A radiographic investigation.

    Science.gov (United States)

    Borgonovo, Andrea Enrico; Taschieri, Silvio; Vavassori, Virna; Re, Dino; Francetti, Luca; Corbella, Stefano

    2017-11-01

    The aim of the present study was to explore, through tridimensional reconstructions of cone-beam computed tomography (CBCT) scans, the presence and the characteristics of mandibular accessory canals. For each included participant, the presence of accessory canals was recorded. The diameter of the canal, as well as the distance between the canal walls and the walls of the mandibular bone (lingual, buccal, cranial and caudal), were measured and recorded. Mandibular accessory canals could be found in 8.8% of participants. Retromolar canals were the most frequently found accessory mandibular canals. Accessory mandibular canals were found in a relatively high number of participants through the examination of CBCT scans and tridimensional reconstruction. The presence of such structures should be considered cautiously when planning and performing surgical interventions in mandibular area. © 2017 John Wiley & Sons Australia, Ltd.

  1. Conditions Of Safe Ship Operations And Sea Waterway Parameters Based On The Reconstruction Of Świnoujście-Szczecin Fairway

    Directory of Open Access Journals (Sweden)

    Gucma Stanisław

    2015-09-01

    Full Text Available This paper describes the state vector of safe ship operation on sea waterways. The author determines relationships between the state vector of safe ship operation and parameters of sea waterway system elements. These include three subsystems: area, navigation and traffic control. These relationships have been exemplified with the 68-kilometre Świnoujście-Szczecin fairway, presently under reconstruction. A systematic approach to sea waterway design is globally unique.

  2. The Suez Canal and the petroleum harbors

    International Nuclear Information System (INIS)

    Anon.

    1997-01-01

    The Suez Canal is the second longest channel in the world and allows to save 60% of the travel time between the petroleum harbors of the Arabic peninsula and Europe. This short paper gives a summary of the main petroleum harbors activity along the channel from the Red sea to the Mediterranean sea. (J.S.)

  3. Middle mesial canals in mandibular molars: incidence and related factors.

    Science.gov (United States)

    Nosrat, Ali; Deschenes, Raney J; Tordik, Patricia A; Hicks, M Lamar; Fouad, Ashraf F

    2015-01-01

    Although the internal anatomy of mandibular molars has been extensively studied, information about middle mesial (MM) canals is limited. The primary aim of this retrospective study was to evaluate the incidence of MM canals in mandibular first and second molars. The secondary aim was to correlate the incidence of MM canals with variables of molar type, sex, age, ethnicity, and presence of a second distal canal. All mature permanent first and second mandibular molars treated from August 2012 to May 2014 were included in the analysis. After completion of root canal instrumentation in all main canals, the clinician inspected the isthmus area of the mesial root using the dental operating microscope. If there was a catch point in this area with a file or explorer, the operator spent more time attempting to negotiate an MM canal. Seventy-five mandibular first and second molars were treated during the specified period. Fifteen (20%) teeth had negotiable MM canals. The incidence of MM canals was 32.1% in patients ≤ 20 years old, 23.8% in patients 21-40 years old, and 3.8% in patients > 40 years. Analysis of data revealed a significant difference in the distribution of MM canals among different age groups (P molar type, and presence of a second distal canal were not significant. The incidence of negotiable MM canals overall and their frequency of identification in younger patients were higher than in previous reports. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  4. Using chloride and other ions to trace sewage and road salt in the Illinois Waterway

    Science.gov (United States)

    Kelly, W.R.; Panno, S.V.; Hackley, Keith C.; Hwang, H.-H.; Martinsek, A.T.; Markus, M.

    2010-01-01

    Chloride concentrations in waterways of northern USA are increasing at alarming rates and road salt is commonly assumed to be the cause. However, there are additional sources of Cl- in metropolitan areas, such as treated wastewater (TWW) and water conditioning salts, which may be contributing to Cl- loads entering surface waters. In this study, the potential sources of Cl- and Cl- loads in the Illinois River Basin from the Chicago area to the Illinois River's confluence with the Mississippi River were investigated using halide data in stream samples and published Cl- and river discharge data. The investigation showed that road salt runoff and TWW from the Chicago region dominate Cl- loads in the Illinois Waterway, defined as the navigable sections of the Illinois River and two major tributaries in the Chicago region. Treated wastewater discharges at a relatively constant rate throughout the year and is the primary source of Cl- and other elements such as F- and B. Chloride loads are highest in the winter and early spring as a result of road salt runoff which can increase Cl- concentrations by up to several hundred mg/L. Chloride concentrations decrease downstream in the Illinois Waterway due to dilution, but are always elevated relative to tributaries downriver from Chicago. The TWW component is especially noticeable downstream under low discharge conditions during summer and early autumn when surface drainage is at a minimum and agricultural drain tiles are not flowing. Increases in population, urban and residential areas, and roadways in the Chicago area have caused an increase in the flux of Cl- from both road salt and TWW. Chloride concentrations have been increasing in the Illinois Waterway since around 1960 at a rate of about 1 mg/L/a. The increase is largest in the winter months due to road salt runoff. Shallow groundwater Cl- concentrations are also increasing, potentially producing higher base flow concentrations. Projected increases in population and

  5. Inland Waterway Environmental Safety

    Science.gov (United States)

    Reshnyak, Valery; Sokolov, Sergey; Nyrkov, Anatoliy; Budnik, Vlad

    2018-05-01

    The article presents the results of development of the main components of the environmental safety when operating vessels on inland waterways, which include strategy selection ensuring the environmental safety of vessels, the selection and justification of a complex of environmental technical means, activities to ensure operation of vessels taking into account the environmental technical means. Measures to ensure environmental safety are developed on the basis of the principles aimed at ensuring environmental safety of vessels. They include the development of strategies for the use of environmental protection equipment, which are determined by the conditions for wastewater treatment of purified sewage and oily bilge water as well as technical characteristics of the vessels, the introduction of the process of the out-of-the-vessel processing of ship pollution as a technology for their movement. This must take into account the operating conditions of vessels on different sections of waterways. An algorithm of actions aimed at ensuring ecological safety of operated vessels is proposed.

  6. Anatomic study on mental canal and incisive nerve canal in interforaminal region in Chinese population.

    Science.gov (United States)

    Xu, Yun; Suo, Ning; Tian, Xiufen; Li, Fei; Zhong, Guangxin; Liu, Xiaoran; Bao, Yongxing; Song, Tao; Tian, Hua

    2015-08-01

    This study was aimed to detect the positions of mental canal and incisive nerve canal as well as the prolongation of mandibular canal in interforaminal region in Chinese population to supply the reference data of the surgical safe zone in chin for clinicians. A total of 80 formalin-fixed semi-mandibles of Chinese adult cadavers were dissected, the positions and courses of mental canal and incisive nerve canal as well as the prolongation of mandibular canal in interforaminal region were measured. The mental foramina were present in all cases (100 %), and most of them were located below 2nd premolar (58.75 %). Accessory mental foramina were observed in 5 %. The anterior end of mandibular canal, extending along the course of 7.37 ± 1.10 mm above the lower border of mandible to interforaminal region about 3.54 ± 0.70 mm medial to the mental foramen, most often ended below between the two premolars (73.75 %), where it continued as the incisive nerve canal (100 %) and the mental canal (96.25 %). Mental canal, with the wall formed by compact bone, being 2.60 ± 0.60 mm in diameter and 4.01 ± 1.20 mm in length, opened into mental foramen. Incisive nerve canal, with the wall formed by thin compact bone and/or partly or completely by spongy bone, being 1.76 ± 0.27 mm in diameter and 24.87 ± 2.23 mm in length, extended to the incisor region along the course of 9.53 ± 1.43 mm above the lower border of mandible, and most often ended below the lateral incisor (70.00 %). This research recommended for chin operations in Chinese population: the surgical safe zone could be set in the region about over 4 mm anterior to the mental foramen, and over 12 mm above inferior border of mandible for anterior alveolar surgery, or within 9 mm above inferior border of mandible for genioplasty.

  7. The influence of hydrology and waterway distance on population structure of Chinook salmon Oncorhynchus tshawytscha in a large river.

    Science.gov (United States)

    Olsen, J B; Beacham, T D; Wetklo, M; Seeb, L W; Smith, C T; Flannery, B G; Wenburg, J K

    2010-04-01

    Adult Chinook salmon Oncorhynchus tshawytscha navigate in river systems using olfactory cues that may be influenced by hydrologic factors such as flow and the number, size and spatial distribution of tributaries. Thus, river hydrology may influence both homing success and the level of straying (gene flow), which in turn influences population structure. In this study, two methods of multivariate analysis were used to examine the extent to which four indicators of hydrology and waterway distance explained population structure of O. tshawytscha in the Yukon River. A partial Mantel test showed that the indicators of hydrology were positively associated with broad-scale (Yukon basin) population structure, when controlling for the influence of waterway distance. Multivariate multiple regression showed that waterway distance, supplemented with the number and flow of major drainage basins, explained more variation in broad-scale population structure than any single indicator. At an intermediate spatial scale, indicators of hydrology did not appear to influence population structure after accounting for waterway distance. These results suggest that habitat changes in the Yukon River, which alter hydrology, may influence the basin-wide pattern of population structure in O. tshawytscha. Further research is warranted on the role of hydrology in concert with waterway distance in influencing population structure in Pacific salmon.

  8. DROUGHTS IN THE TIETÊ-PARANÁ WATERWAY: IMPACTS ON THE DIRECT, INDIRECT AND HIDDEN COSTS IN THE TRANSPORTATION OF SOYBEAN.

    Directory of Open Access Journals (Sweden)

    Rodrigo Carlo Toloi

    2016-05-01

    Full Text Available Brazil's agricultural economy is growing and increasing productivity. Therefore, it has required transportation systems with high load capacity and lower transportation costs. However, with the drought in the Southeast region of Brazil, the waterway Tietê-Paraná closed since May 2014 generating a loss of more than 30 million last year. Thus, this study investigates the impacts on direct, indirect and hidden costs resulting from this change of route for soy transport. The methodology consists of an exploratory, descriptive and bibliographic research that seeks to raise the main costs. The results show that failing to ensure the production of soybeans by the Tiete-Parana waterway and using the highway transportation costs for waterway users are increased by US$ 37,760,146.86.

  9. CLIMATE CHANGE AND THE RISK MANAGEMENT IN SERBIAN INLAND WATERWAY TRANSPORT

    Directory of Open Access Journals (Sweden)

    Todor Backalic

    2012-12-01

    Full Text Available Climate changes require special attention and global monitoring. Impacts on nature and industry are increasingly evident. Water transport could be the backbone of the future European combined transport system. Unfortunately, risks in water transport are perhaps an under researched area and consequently, this article outlines a rationale, why it is necessary to develop competence about risk in water transport. The development of the cargo transport in river traffic depends directly on technical-exploitative characteristics of the network of inland waterways. Research of navigational abilities of inland waterways always comes before building ships or making a transport schedule. Navigation characteristics of rivers have to be determined as precise as possible, especially from the aspect of determination the possible draught of vessels. River transport due to their operational business and environmental conditions faced with several risks having different degrees of consequences. Current risk assessment methods for water transport just consider some dramatic events. We present a new method for the assessment of risk and vulnerability of water transport where river depth represents a crucial part. The analysis of water level changes on Serbian rivers during the last sixty years was done.

  10. NMR imaging of the vertebral column and the spinal canal. 2. rev. and enl. ed.

    International Nuclear Information System (INIS)

    Forsting, Michael; Uhlenbrock, Detlev; Wanke, Isabel; Universitaetsklinikum Essen

    2009-01-01

    The book on the MRT (magnetic resonance tomography) of the vertebral cord and spinal canal covers the following topics: physics fundamentals and application; malformation of the spinal canal; degenerative vertebral column diseases; vertebral column and spinal canal carcinomas; inflammatory diseases of the vertebral column and the spinal canal; applicability of MRT in case of acute spinal cord traumata; vascular diseases of the spinal canal

  11. Diagnosis and root canal treatment in a mandibular premolar with three canals.

    Science.gov (United States)

    Soares, Lanuce Rosa; Arruda, Marcos; de Arruda, Marcos Pôrto; Rangel, Andréa Leão; Takano, Edson; de Carvalho Júnior, Jacy Ribeiro; Saquy, Paulo Cesar

    2009-01-01

    This paper presents a case report of a left mandibular second premolar with three canals and three different apical foramina. A 39-year-old male patient presented to our clinic with pain in the mandibular left second premolar. Initially, pain was caused by cold stimulus and later was spontaneously. The intraoral clinical examination revealed a fractured amalgam restoration with occlusal caries. Percussion and cold (Endo-Frost) tests were positive. The radiographic examination showed the presence of two roots. The probable diagnosis was an acute pulpitis. After access cavity, it was observed remaining roof of the pulp chamber and mild bleeding in the tooth lingual area, indicating the possible presence of a third canal. The endodontic treatment was completed in a single session using Root ZX apex locator and K3 NiTi rotary system with surgical diameter corresponding to a .02/45 file in the three canals and irrigation with 1% sodium hypochlorite. The canals were obtured with gutta-percha cones and Sealer 26 using the lateral condensation technique. After 1 year of follow-up, the tooth was asymptomatic and periapical repair was observed radiographically. Internal alterations should be considered during the endodontic treatment of mandibular second premolars. The correct diagnosis of these alterations by the analysis of preoperative radiographs can help the location of two or more canals, thereby avoiding root therapy failure.

  12. The behaviour of radium in waterways and aquifers

    International Nuclear Information System (INIS)

    1984-01-01

    The Coordinated Research Program was designed to develop systematic information on the form and movement of radium in water under a range of environmental conditions. The final report contains: a) Selection and standardization of methods for determination of radium in water; b) The distribution of soluble and insoluble radium in natural waters, affected by mining or milling operations; c) The factors affecting the leaching rate from ore heaps and tailings piles; d) The uptake of radium by biological systems, especially those which form part of man's food chain. This information being of great value to those authorities responsible for assessing the consequences of radium releases to water and to those responsible for setting discharge limits

  13. Environmental pollution and shipping feasibility of the Nicaragua Canal.

    Science.gov (United States)

    Chen, Jihong; Zeng, Xin; Deng, Yibing

    2016-12-15

    In recent years, the Nicaraguan government's renewed interest in constructing this interoceanic canal has once again aroused widespread concern, particularly in the global shipping industry. The project's immense ecological risks, coupled with the recent expansions of both the Panama Canal and the Suez Canal, have raised questions among scientists and experts about its viability. Whether the Nicaragua Canal is really feasible for international shipping, given its high marine pollution risks, requires the further study. This paper discusses and analyses the feasibility of the Nicaragua Canal in the context of its environmental impact and value as a shipping service. This paper aims to provide an important information reference to inform strategic decision-making among policymakers and stakeholders. Our research results indicate that the environmental complexity, economic costs and safety risks of building a new transoceanic canal are simply too high to justify the project. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Canal Centring Ability of ProTaper and Mtwo Rotary Systems in Curved Canals

    Directory of Open Access Journals (Sweden)

    Turkaydin Dilek Erbay

    2014-07-01

    Full Text Available The purpose of this investigation was to compare centring ratio of ProTaper and Mtwo rotary systems. 60 mandibular molar teeth which had 25, 30 and 35 degree curvature in mesio-buccal root canal were used. Group 1 had 25°, Group 2 had 30°, and Group 3 had 35° curvatures. The roots were sectioned horizontally at 2 mm away from the apex. The apical region was then observed under a stereo-microscope. In each group, teeth were instrumented using ProTaper and Mtwo systems. After canal preparation, digital images of apical part of canals were taken. These images were then superimposed by using Adobe Photoshop CS2 programme. The data were analyzed using ANOVA and Student’s t-test.

  15. ROOT CANAL IRRIGANTS AND IRRIGATION TECHNIQUES: A REVIEW

    OpenAIRE

    Aniketh; Mohamed; Geeta; Nandakishore; Gourav Kumar; Patrick Timothy; Jayson Mathew; Sahle Abdul

    2015-01-01

    Root canal irrigation is not much emphasised in endodontic therapy. Most articles discussed are on root canal shaping and obturation not much emphasis is given for irrigation. There are many irrigation solutions which are introduced into market. The primary objective of root canal therapy is the ret ention of the pulpless or pulpally involved tooth with its associated periapical tissues in a healthy state. Achievement of this objective requires that the pulpal spaces and con...

  16. Environmental pollution and shipping feasibility of the Nicaragua Canal

    International Nuclear Information System (INIS)

    Chen, Jihong; Zeng, Xin; Deng, Yibing

    2016-01-01

    In recent years, the Nicaraguan government's renewed interest in constructing this interoceanic canal has once again aroused widespread concern, particularly in the global shipping industry. The project's immense ecological risks, coupled with the recent expansions of both the Panama Canal and the Suez Canal, have raised questions among scientists and experts about its viability. Whether the Nicaragua Canal is really feasible for international shipping, given its high marine pollution risks, requires the further study. This paper discusses and analyses the feasibility of the Nicaragua Canal in the context of its environmental impact and value as a shipping service. This paper aims to provide an important information reference to inform strategic decision-making among policymakers and stakeholders. Our research results indicate that the environmental complexity, economic costs and safety risks of building a new transoceanic canal are simply too high to justify the project. - Highlights: • The Nicaragua Canal is a long-standing controversial maritime project. • We develop specific analysis of the high environmental pollution risks of the canal. • The shipping service feasibility of the canal is faced with great uncertainty. • The government and stakeholders are suggested to be discreet to the mega project.

  17. GEOPOLITICS AND TRANSPORTATION. UNITED STATES AND PANAMA CANAL

    Directory of Open Access Journals (Sweden)

    Benea Ciprian Beniamin

    2009-05-01

    Full Text Available This article presents the great connection which exists between the realization of Panama Canal and the rising power on United States; and how this state, after the construction of this canal, could promote efficiently at global level its interests.

  18. A Two-Ocean Bouillabaisse: Science, Politics, and the Central American Sea-Level Canal Controversy.

    Science.gov (United States)

    Keiner, Christine

    2017-11-01

    As the Panama Canal approached its fiftieth anniversary in the mid-1960s, U.S. officials concerned about the costs of modernization welcomed the technology of peaceful nuclear excavation to create a new waterway at sea level. Biologists seeking a share of the funds slated for radiological-safety studies called attention to another potential effect which they deemed of far greater ecological and evolutionary magnitude - marine species exchange, an obscure environmental issue that required the expertise of underresourced life scientists. An enterprising endeavor to support Smithsonian naturalists, especially marine biologists at the Smithsonian Tropical Research Institute in Panama, wound up sparking heated debates - between biologists and engineers about the oceans' biological integrity and among scientists about whether the megaproject represented a research opportunity or environmental threat. A National Academy of Sciences panel chaired by Ernst Mayr failed to attract congressional funding for its 10-year baseline research program, but did create a stir in the scientific and mainstream press about the ecological threats that the sea-level canal might unleash upon the Atlantic and Pacific. This paper examines how the proposed megaproject sparked a scientific and political conversation about the risks of mixing the oceans at a time when many members of the scientific and engineering communities still viewed the seas as impervious to human-facilitated change.

  19. 77 FR 22769 - Amendment to the Inland Waterways Users Board

    Science.gov (United States)

    2012-04-17

    ... DEPARTMENT OF DEFENSE Office of the Secretary Amendment to the Inland Waterways Users Board AGENCY... charter for the Inland Waterways Users Board (hereafter referred to as ``the Board''). The Board is... shall invite primary commercial users and shippers of the inland and intracoastal waterways to serve on...

  20. Transportation Lines on the Mississippi River System and the Gulf Intracoastal Waterway; Transportation Series 4; 1980.

    Science.gov (United States)

    1982-05-01

    EMERALD SEA0SE C_ 133 -.664 17&0 340 3F0 110 𔃺 22js !3 12 t Lo DO 1971 GULF S6*śSE T 66 1010 1100 250 250 90 50 15uC 7C 1530 , -AS,_ 0 DO 1970INDIAN...130 Do 933 1053 1950 3S0 3-0 90 290 - ISOS 1.S. COvkas 19,7 !91. 115-119 00 175 - 1950 - 3S5 99 L6 - 2Q.3, 33 1993 (29 1v0 IVE LOGIN CC, L.ILT J02...WR, C., 4 SONS 2 CHARTERS To OTHERS 4ISSISSIPPI RIVER BYSTEM 33 EMERALD MARINE SERVICE, INC. 2 TOWING AND DRY CARGT 06 INTRACOASTAL WATERWAY Of

  1. Three distal root canals in mandibular first molar with different canal configurations: Report of two cases and literature review

    Directory of Open Access Journals (Sweden)

    Parul Bansal

    2015-01-01

    Full Text Available With the increasing number of reports of aberrant root canal morphology, the clinician needs to be aware of the variable anatomy. Various case reports have been published with the finding of middle mesial canal in mandibular first molar, however finding of three distal canals in distal roots of mandibular first molar is rare. This article reports endodontic management of two mandibular first molars presented with three distal canals present in a single distal root (Sert and Bayirli type XVIII and distal and distolingual root.

  2. Maxillary second molar with four roots and five canals

    Directory of Open Access Journals (Sweden)

    Xinjia Sha

    2018-06-01

    Full Text Available In this case report, we present a maxillary second molar variant, which had two palatal roots with two canals and two buccal roots with three canals, including a second mesiobuccal canal. A 44-year-old female patient complained about a tooth crown fracture and severe pain in her right maxillary second molar. A clinical intraoral inspection and radiography were carried out on the tooth, and a diagnosis of chronic apical periodontitis was made. Four roots (two buccal and two palatal and five canals (three buccal and two palatal were found. The anatomical variation of the tooth was further confirmed by cone-beam computed tomography, a cone-fit procedure, and a radiograph with a shifted projection angle. Root-canal treatment was performed under an endodontic microscope.

  3. Improvement on the Performance of Canal Network and Method of ...

    African Journals Online (AJOL)

    This paper presents the required improvement on the performance of canal network and method of on-farm water application systems at Tunga-Kawo irrigation scheme, Wushishi, Niger state. The problems of poor delivery of water to the farmland were identified to include erosion of canal embarkment, lack of water ...

  4. Effects of irrigation solutions and Calcium hydroxide dressing on root canal treatments of periapical lesions

    OpenAIRE

    Nirmala, Vita

    2006-01-01

    The preparation of root canal in endodontic treatment plays an important role in treating non vital teeth with periapical lesion. Some factors influence the success of root canal treatment in short and long terms are the irrigation of root canal using antiseptic solution and the use of root canal medicament. The aim of this literature study is to determined the effect of irrigation solution and Calcium hydroxide dressing in root canal treatment of periapical lesions. The use of root canal med...

  5. Hydrology and environmental aspects of Erie Canal (1817-99)

    Science.gov (United States)

    Langbein, Walter Basil

    1976-01-01

    As the first major water project in the United States, the old Erie Canal provides an example of the hydrological and environmental consequences of water development. The available record shows that the project aroused environmental fears that the canal might be impaired by the adverse hydrologic effects of land development induced by the canal. Water requirements proved greater than anticipated, and problems of floods and hydraulic inefficiencies beset navigation throughout its history. The Erie Canal proved the practicality of major hydraulic works to the extent that operations and maintenance could cope with the burdens of deficiencies in design. The weight of prior experience that upland streams, such as the Potomac and Mohawk Rivers, had proved unsatisfactory for dependable navigation, led to a decision to build an independent canal which freed the location from the constraints of river channels and made possible a cross-country water route directly to Lake Erie. The decision on dimensioning the canal prism--chiefly width and depth-involved balance between a fear of building too small and thus not achieving the economic potentials, and a fear of building too expensively. The constraints proved effective, and for the first part of its history the revenues collected were sufficient to repay all costs. So great was the economic advantage of the canal that the rising trend in traffic soon induced an enlargement of the canal cross section, based upon a new but riskier objective-build as large as the projected trend in toll revenues would finance. The increased revenues did not materialize. Water supplies were a primary concern for both the planners and the operators of the canal. Water required for lockage, although the most obvious to the planners, proved to be a relatively minor item compared with the amounts of water that were required to compensate for leakage through the bed and banks of the canal. Leakage amounted to about 8 inches of depth per day. The total

  6. Bank erosion processes in waterways

    NARCIS (Netherlands)

    Duro, G.; Uijttewaal, W.S.J.; Kleinhans, M; Crosato, A.

    2017-01-01

    Waterways serve for several functions besides  transporting goods and people. The ecological  importance of navigable rivers has taken much  attention during recent decades bringing efforts  to improve these natural corridors for fauna and  flora (Boeters et al.,

  7. Kiel Canal: Past and future threats for shipping resulting from precipitation, wind surge and sea level rise

    Science.gov (United States)

    Ganske, Anette; Hüttl-Kabus, Sabine; Möller, Jens; Schade, Nils; Heinrich, Hartmut; Tinz, Birger

    2017-04-01

    The Kiel Canal is the most frequented artificial waterway in the world. It connects the North Sea and the Hamburg Harbor with the Baltic Sea and has a length of about 100 km. The Canal receives its water from the upper catchment of the river Eider. Discharge from the Canal towards the North Sea is via the sluices at Brunsbüttel (90%) into river Elbe and into the Baltic Sea via the sluices at Kiel-Holtenau. A risk of closure of the Canal occurs when high precipitation in the catchment meets high water levels in the river Elbe and/or the Baltic preventing the discharge of excess Canal water. Future sea level rise jointly with other effects such as possibly increasing wind surge and precipitation will close the gap between the inner and outer water levels, so that someday the outside levels will surmount the inner one. The German Federal Ministry of Transport and Digital Infrastructure (BMVI) tasked its internal Network of Experts to run a case study on the evolution of critical water levels in order to estimate risks and vulnerabilities for adaptation measures. First step of the investigation is a search for factors or combination of factors responsible for closures in the past. Candidates are factors such as higher water levels at low tides, high precipitation events on land, soil moisture and human factors like preventive water management measures. Second step will be the search for the natural criteria in climate projections. Here we report on the results of the first step of the case study with a focus on the exit towards the North Sea. There, discharge is possible only during low tide. Presently still sufficient difference in height exists between the levels in the Canal and the river Elbe allowing for a free flow of excess Canal water. Shipping is ceased when levels in the Canal surpass safety limits due to high precipitation events in the catchment jointly with high outer water levels. We used atmospheric data from ERA-Interim reanalysis instead of gauge data

  8. Geographic Information System (GIS) characterization of benthic and emergent areas in the Intracoastal Waterway, Sarasota County, Florida in 1987 (NODC Accession 0000607)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This GIS layer graphically represents algae, seagrass, tidal marshes, mangroves, and oyster bed coverages found throughout the Intracoastal Waterway in Sarasota...

  9. Influences of the separation distance, ship speed and channel dimension on ship maneuverability in a confined waterway

    Science.gov (United States)

    Du, Peng; Ouahsine, Abdellatif; Sergent, Philippe

    2018-05-01

    Ship maneuvering in the confined inland waterway is investigated using the system-based method, where a nonlinear transient hydrodynamic model is adopted and confinement models are implemented to account for the influence of the channel bank and bottom. The maneuvering model is validated using the turning circle test, and the confinement model is validated using the experimental data. The separation distance, ship speed, and channel width are then varied to investigate their influences on ship maneuverability. With smaller separation distances and higher speeds near the bank, the ship's trajectory deviates more from the original course and the bow is repelled with a larger yaw angle, which increase the difficulty of maneuvering. Smaller channel widths induce higher advancing resistances on the ship. The minimum distance to the bank are extracted and studied. It is suggested to navigate the ship in the middle of the channel and with a reasonable speed in the restricted waterway.

  10. Gender and laterality in semicircular canal dehiscence syndrome.

    Science.gov (United States)

    Karimnejad, K; Czerny, M S; Lookabaugh, S; Lee, D J; Mikulec, A A

    2016-08-01

    To determine if there is gender or laterality predilection in patients with semicircular canal dehiscence syndrome. A multi-institutional chart review was performed to identify patients diagnosed with semicircular canal dehiscence between 2000 and 2015. A systematic literature search was conducted using PubMed to further identify patients with semicircular canal dehiscence. Age, gender and laterality data were collected. Statistical analysis was performed to evaluate for gender or laterality preponderance. A total of 682 patients with semicircular canal dehiscence were identified by literature and chart review. Mean age of diagnosis was 49.75 years (standard deviation = 15.33). Semicircular canal dehiscence was associated with a statistically significant female predominance (chi-square = 7.185, p = 0.007); the female-to-male ratio was 1.2 to 1. Left-sided semicircular canal dehiscence was most common, followed by right-sided then bilateral (chi-square = 23.457, p < 0.001). Semicircular canal dehiscence syndrome is most commonly left-sided and exhibits a female predominance. This may be secondary to morphological cerebral hemisphere asymmetries in both sexes and a predilection of women to seek more medical care than men.

  11. Exploring the links between natural resource use and biophysical status in the waterways of the North Rupununi, Guyana.

    Science.gov (United States)

    Mistry, Jayalaxshmi; Simpson, Matthews; Berardi, Andrea; Sandy, Yung

    2004-09-01

    The North Rupununi District in south-west Guyana is comprised of a mosaic of ecosystems, including savannas, wetlands and forests, and is home to the Makushi Amerindians, who depend on the waterways for their subsistence needs. With logging and mining seen as increasing threats to the region, it is necessary to look at methods for engaging stakeholders in monitoring the status of their natural resources. This paper presents the results of a pilot study carried out to investigate water use by the Makushi Amerindians, and collect baseline data on the hydro-morphological aspects of the waterways. Methods included informal interviews, the use of the River Habitat Survey (RHS), and water quality measurements. The results indicate the heavy reliance of the Makushi on the waterways for their daily lives, particularly on fishing. Although ponds and creeks are important sources of fish, the rivers provide much larger catches of a greater diversity of fish species, both in the wet and dry seasons. The physical characteristics of the water sources used by the Makushi are mainly associated with the surrounding habitat types: the savanna areas containing the more nutrient rich white-water rivers, and the tropical forest areas containing the less nutrient rich black-water rivers. This study indicates that at present there is no direct evidence of adverse impacts on the waterways used by the Makushi in terms of fish catches, habitat conditions and water quality. A monitoring scheme was set up using this study's outputs as a baseline from which any future changes can be compared. Further work is to be carried out over the next three years to produce monitoring and sustainable management procedures for the North Rupununi ecosystems, by linking the physical attributes of the environment to biodiversity and subsequently local livelihoods, and by building capacity of local stakeholders through training.

  12. Controls on denitrification potential in nitrate-rich waterways and riparian zones of an irrigated agricultural setting.

    Science.gov (United States)

    Webster, Alex J; Groffman, Peter M; Cadenasso, Mary L

    2018-02-21

    Denitrification, the microbial conversion of NO 3 - to N gases, is an important process contributing to whether lotic and riparian ecosystems act as sinks for excess NO 3 - from agricultural activities. Though agricultural waterways and riparian zones have been a focus of denitrification research for decades, almost none of this research has occurred in the irrigated agricultural settings of arid and semi-arid climates. In this study, we conducted a broad survey of denitrification potential in riparian soils and channel sediment from 79 waterway reaches in the irrigated agricultural landscape of California's Central Valley. With this approach, we sought to capture the wide range of variation that arose from diverse waterway management and fluctuating flow conditions, and use this variation to identify promising management interventions. We explored associations of denitrification potentials with surface water NO 3 - -N, organic matter, flow conditions, vegetation cover, near-channel riparian bank slope, and channel geomorphic features using generalized linear mixed models. We found strong associations of sediment denitrification potentials with reach flow conditions, which we hypothesize was the result of variation in microbial communities' tolerance to dry-wet cycles. Denitrification potentials in riparian soils, in contrast, did not appear affected by flow conditions, but instead were associated with organic matter, vegetation cover, and bank slope in the riparian zone. These results suggest a strong need for further work on how denitrification responds to varying flow conditions and dry-wet cycles in non-perennial lotic ecosystems. Our findings also demonstrate that denitrifier communities respond to key features of waterway management, which can therefore be leveraged to control denitrification through a variety of management actions. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  13. Research note: Mapping spatial patterns in sewer age, material, and proximity to surface waterways to infer sewer leakage hotspots

    Science.gov (United States)

    Hopkins, Kristina G.; Bain, Daniel J.

    2018-01-01

    Identifying areas where deteriorating sewer infrastructure is in close proximity to surface waterways is needed to map likely connections between sewers and streams. We present a method to estimate sewer installation year and deterioration status using historical maps of the sewer network, parcel-scale property assessment data, and pipe material. Areas where streams were likely buried into the sewer system were mapped by intersecting the historical stream network derived from a 10-m resolution digital elevation model with sewer pipe locations. Potential sewer leakage hotspots were mapped by identifying where aging sewer pipes are in close proximity (50-m) to surface waterways. Results from Pittsburgh, Pennsylvania (USA), indicated 41% of the historical stream length was lost or buried and the potential interface between sewers and streams is great. The co-location of aging sewer infrastructure (>75 years old) near stream channels suggests that 42% of existing streams are located in areas with a high potential for sewer leakage if sewer infrastructure fails. Mapping the sewer-stream interface provides an approach to better understand areas were failing sewers may contribute a disproportional amount of nutrients and other pathogens to surface waterways.

  14. A history of trade routes and water-level regulation on waterways in Voyageurs National Park, Minnesota, USA

    Science.gov (United States)

    Christensen, Victoria G.; LaBounty, Andrew E.

    2018-01-01

    Unlike most national parks, main access to Voyageurs National Park is by boat. This remote system of interconnected waterways along the USA-Canada border was an important transportation route for thousands of years of American Indian occupation, leading up to and including the trade route of the voyageurs, or French-Canadian fur traders from around 1680 to 1870. The Ojibwe people collaborated with the voyageurs and the two cultures developed a trade network that continued to rely on these waterways. By the mid-1800s, European fashion changed, and the fur trade dwindled while the Ojibwe remained tied to the land and waters. The complexity of the waterways increased with the installation of dams on two of the natural lakes in the early 1900s. Modern water levels have affected—and in some cases destabilized—vulnerable landforms within the past century. The knowledge of these effects can be used by resource managers to weigh the consequences of hydrologic manipulation in Voyageurs National Park.

  15. Detection of Mesiobuccal Canal in Maxillary Molars and Distolingual Canal in Mandibular Molars by Dental CT: A Retrospective Study of 100 Cases

    Directory of Open Access Journals (Sweden)

    Sushma Rathi

    2010-01-01

    Full Text Available Objective. To detect presence of MB2 canal in maxillary molars and distolingual canal in mandibular molars by Dental CT. Material and Methods. A retrospective study of 100 Dental CTs was done. Axial and paraxial images obtained were used to assess the presence of MB2 canal in maxillary molars and distolingual canal in mandibular molars. Results. The youngest patient was of 11 years while the eldest patient was of 77 years. Males were 58 in number and females were 42 in number. MB2 canals were present in 57 patients and distolingual canal was present in 18 patients. Maximum MB2 canals were present in age group between 51 and 60 years, while distolingual canals were present in age group of 21–30 years. Conclusion. Dental CT allows adequate visualization of variation in root canal morphology and can be important diagnostic tool for successful endodontic therapy.

  16. Molecular mechanisms of canalization: Hsp90 and beyond

    Indian Academy of Sciences (India)

    2006-03-26

    Mar 26, 2006 ... ... and regulatory circuits, accounting for the important role Hsp90 plays in ... by environmental stress, genetic or pharmaceutical targeting of Hsp90. The ... Here, we discuss the role of Hsp90 in canalization and organismal ...

  17. 46 CFR 69.7 - Vessels transiting the Panama and Suez Canals.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Vessels transiting the Panama and Suez Canals. 69.7... MEASUREMENT OF VESSELS MEASUREMENT OF VESSELS General § 69.7 Vessels transiting the Panama and Suez Canals. (a... Canal must be measured and certificated under the Arab Republic of Egypt Suez Canal Authority Rules of...

  18. Nuclear magnetic imaging for MTRA. Spinal canal and spinal cord

    International Nuclear Information System (INIS)

    Fritzsch, Dominik; Hoffmann, Karl-Titus

    2011-01-01

    The booklet covers the following topics: (1) Clinical indications for NMR imaging of spinal cord and spinal canal; (2) Methodic requirements: magnets and coils, image processing, contrast media: (3) Examination technology: examination conditions, sequences, examination protocols; (4) Disease pattern and indications: diseases of the myelin, the spinal nerves and the spinal canal (infections, tumors, injuries, ischemia and bleedings, malformations); diseases of the spinal cord and the intervertebral disks (degenerative changes, infections, injuries, tumors, malformations).

  19. A numerical study on ship-ship interaction in shallow and restricted waterway

    Directory of Open Access Journals (Sweden)

    Sungwook Lee

    2015-09-01

    Full Text Available In the present study, a numerical prediction method on the hydrodynamic interaction force and moment between two ships in shallow and restricted waterway is presented. Especially, the present study proposes a methodology to overcome the limitation of the two dimensional perturbation method which is related to the moored-passing ship interaction. The validation study was performed and compared with the experiment, firstly. Afterward, in order to propose a methodology in terms with the moored-passing ship interaction, further studies were performed for the moored-passing ship case with a Reynolds Averaged Navier-Stokes (RANS calculation which is using OpenFOAM with Arbitrary Coupled Mesh Interface (ACMI technique and compared with the experiment result. Finally, the present study proposes a guide to apply the two dimensional perturbation method to the moored-passing ship interaction. In addition, it presents a possibility that the RANS calculation with ACMI can applied to the ship-ship interaction without using a overset moving grid technique.

  20. First Branchial Cleft Fistula Associated with External Auditory Canal Stenosis and Middle Ear Cholesteatoma

    Science.gov (United States)

    Abdollahi fakhim, Shahin; Naderpoor, Masoud; Mousaviagdas, Mehrnoosh

    2014-01-01

    Introduction: First branchial cleft anomalies manifest with duplication of the external auditory canal. Case Report: This report features a rare case of microtia and congenital middle ear and canal cholesteatoma with first branchial fistula. External auditory canal stenosis was complicated by middle ear and external canal cholesteatoma, but branchial fistula, opening in the zygomatic root and a sinus in the helical root, may explain this feature. A canal wall down mastoidectomy with canaloplasty and wide meatoplasty was performed. The branchial cleft was excised through parotidectomy and facial nerve dissection. Conclusion: It should be considered that canal stenosis in such cases can induce cholesteatoma formation in the auditory canal and middle ear. PMID:25320705

  1. First branchial cleft fistula associated with external auditory canal stenosis and middle ear cholesteatoma.

    Science.gov (United States)

    Abdollahi Fakhim, Shahin; Naderpoor, Masoud; Mousaviagdas, Mehrnoosh

    2014-10-01

    First branchial cleft anomalies manifest with duplication of the external auditory canal. This report features a rare case of microtia and congenital middle ear and canal cholesteatoma with first branchial fistula. External auditory canal stenosis was complicated by middle ear and external canal cholesteatoma, but branchial fistula, opening in the zygomatic root and a sinus in the helical root, may explain this feature. A canal wall down mastoidectomy with canaloplasty and wide meatoplasty was performed. The branchial cleft was excised through parotidectomy and facial nerve dissection. It should be considered that canal stenosis in such cases can induce cholesteatoma formation in the auditory canal and middle ear.

  2. Digital waterway construction based on inland electronic navigation chart

    Science.gov (United States)

    Wang, Xue; Pan, Junfeng; Zhu, Weiwei

    2015-12-01

    With advantages of large capacity, long distance, low energy consumption, low cost, less land occupation and light pollution, inland waterway transportation becomes one of the most important constituents of the comprehensive transportation system and comprehensive water resources utilization in China. As one of "three elements" of navigation, waterway is the important basis for the development of water transportation and plays a key supporting role in shipping economic. The paper discuss how to realize the informatization and digitization of waterway management based on constructing an integrated system of standard inland electronic navigation chart production, waterway maintenance, navigation mark remote sensing and control, ship dynamic management, and water level remote sensing and report, which can also be the foundation of the intelligent waterway construction. Digital waterway construction is an information project and also has a practical meaning for waterway. It can not only meet the growing high assurance and security requirements for waterway, but also play a significant advantage in improving transport efficiency, reducing costs, promoting energy conservation and so on. This study lays a solid foundation on realizing intelligent waterway and building a smooth, efficient, safe, green modern inland waterway system, and must be considered as an unavoidable problem for the coordinated development between "low carbon" transportation and social economic.

  3. Unusal canal configuration in maxillary and mandibular second molars

    Directory of Open Access Journals (Sweden)

    Ramachandran Ragunathan

    2016-01-01

    Full Text Available This clinical article describes three different case reports of maxillary and mandibular second molars with the unusual anatomy of single root with a single canal and their endodontic management. An unusual case of bilateralism is observed in the first two cases in the form of single-rooted second mandibular molars in both the quadrant of the same patient. The presence of maxillary second molar with single root and single canal in the third case is unusual.

  4. Article Review: Lessepsian migration of zooplankton through Suez Canal and its impact on ecological system

    Directory of Open Access Journals (Sweden)

    Howaida Y. Zakaria

    2015-01-01

    Full Text Available The marine environment of the East Mediterranean has been considerably impacted in modern times by two man-made changes: the creation of a waterway between the Indo-Pacific and the Mediterranean basins and the control of the Nile fresh-water outflow. The opening of the Suez Canal caused a migration generally from the Red Sea to the Mediterranean, and rarely in the opposite direction as the Red Sea is generally saltier and more nutrient-poor than the Atlantic, so the Red Sea species have advantages over Atlantic species in the salty and nutrient-poor eastern Mediterranean. Accordingly Red Sea species invaded the Mediterranean ecosystem and not vice versa; this phenomenon is known as the Lessepsian migration or erythrean invasion. The composition of zooplankton in the eastern Mediterranean has been shown to include a large proportion of Indo-Pacific and other circumtropical species which have successfully settled and proliferated in this environment. During the present study, an overview is provided on zooplankton migration through Suez Canal and its impact on the ecological system based on published literature. It is also meant with the hydrographic and zooplankton characteristics of the adjacent seas. It is clear that, except jellyfish Rhopilema nomadica, the negative impact of zooplankton Lessepsian migratory species in the Egyptian Mediterranean waters is not evident. Finally, it would be concluded that, a continuous monitoring programme will be needed to record the recent erythrean zooplankton species and follow up the distribution and abundance of those previously recorded as aliens to assess their impacts on the native biodiversity of the Mediterranean.

  5. Biomarker responses and PAH ratios in fish inhabiting an estuarine urban waterway.

    Science.gov (United States)

    Duarte, Rafael Mendonça; Sadauskas-Henrique, Helen; de Almeida-Val, Vera Maria Fonseca; Val, Adalberto Luis; Nice, Helen Elizabeth; Gagnon, Marthe Monique

    2017-10-01

    Many cities worldwide are established adjacent to estuaries and their catchments resulting in estuarine contamination due to intense anthropogenic activities. The aim of this study was to evaluate if fish living in an estuarine urban waterway were affected by contamination, via the measurement of a suite of biomarkers of fish health. Black bream (Acanthopagrus butcheri) were sampled in a small urban embayment and a suite of biomarkers of fish health measured. These were condition factor (CF), liver somatic index (LSI), gonadosomatic index (GSI), hepatic EROD activity, polycyclic aromatic hydrocarbon (PAH) biliary metabolites, serum sorbitol dehydrogenase (s-SDH) and branchial enzymes cytochrome C oxidase (CCO), and lactate dehydrogenase (LDH) activities. The biomarkers of exposure EROD activity, and pyrene- and B(a)P-type biliary metabolites confirmed current or recent exposure of the fish and that fish were metabolizing contaminants. Relative to a reference site, LSI was higher in fish collected in the urban inlet as was the metabolic enzyme LDH activity. CF, GSI, s-SDH, CCO, and naphthalene-type metabolites were at similar levels in the urban inlet relative to the reference site. PAH biliary metabolite ratios of high-molecular-weight to low-molecular-weight suggest that fish from the urban inlet were exposed to pyrogenic PAHs, likely from legacy contamination and road runoff entering the embayment. Similarly, the sediment PAH ratios and the freshness indices suggested legacy contamination of a pyrogenic source, likely originating from the adjacent historic gasworks site and a degree of contamination of petrogenic nature entering the inlet via storm water discharge. Biomarkers of exposure and effect confirmed that black bream collected in the Claisebrook Cove inlet, Western Australia, are currently exposed to contamination and are experiencing metabolic perturbations not observed in fish collected at a nearby reference site. © 2017 Wiley Periodicals, Inc.

  6. Cervical spinal canal narrowing and cervical neurologi-cal injuries

    Directory of Open Access Journals (Sweden)

    ZHANG Ling

    2012-04-01

    Full Text Available 【Abstract】Cervical spinal canal narrowing can lead to injury of the spinal cord and neurological symptoms in-cluding neck pain, headache, weakness and parasthesisas. According to previous and recent clinical researches, we investigated the geometric parameters of normal cervical spinal canal including the sagittal and transverse diameters as well as Torg ratio. The mean sagittal diameter of cervical spinal canal at C 1 to C 7 ranges from 15.33 mm to 20.46 mm, the mean transverse diameter at the same levels ranges from 24.45 mm to 27.00 mm and the mean value of Torg ratio is 0.96. With respect to narrow cervical spinal canal, the following charaterstics are found: firstly, extension of the cervical spine results in statistically significant stenosis as compared with the flexed or neutral positions; secondly, females sustain cervical spinal canal narrowing more easily than males; finally, the consistent narrowest cervical canal level is at C 4 for all ethnicity, but there is a slight variation in the sagittal diameter of cervical spinal stenosis (≤14 mm in Whites, ≤ 12 mm in Japanese, ≤13.7 mm in Chinese. Narrow sagittal cervical canal diameter brings about an increased risk of neurological injuries in traumatic, degenerative and inflam-matory conditions and is related with extension of cervical spine, gender, as well as ethnicity. It is hoped that this re-view will be helpful in diagnosing spinal cord and neuro-logical injuries with the geometric parameters of cervical spine in the future. Key words: Spinal cord injuries; Spinal stenosis; Trauma, nervous system

  7. On the Waterway Staff Training Management and Innovation%试论航道员工培训管理与创新

    Institute of Scientific and Technical Information of China (English)

    镇卫兵

    2014-01-01

    近年来我国航道事业随着社会经济的快速发展越来越被重视,航道作为水路运输的重要组成部分,其管理状况对水运发展起着直接影响作用。本文通过对航道现行体制与管理情况探讨,结合员工培训管理与创新分析,提出加强航道管理水平的策略,以实现水运交通事业快速持续健康发展的目标。%In recent years, with the rapid development of social economy, waterway business in China has been paid more and more attention. As an important part of water transportation, waterway's management conditions have a direct impact on water transportation development. Through the discussion of current system and management conditions of waterway, combined with analysis of employee training management and innovation, this article puts forward the strategies to strengthen the waterway management level, in order to achieve the goal of rapid, sustainable and healthy development of waterway transportation business.

  8. CT and MR Imagings of Semicircular Canal Aplasia

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Chung Hee; Hong, Hyun Sook; Yi, Beom Ha; Cha, Jang Gyu; Park, Seong Jin; Kim, Dae Ho; Lee, Hae Kyung; Kim, Shi Chan [Soonchunhyang University Bucheon Hospital, Bucheon (Korea, Republic of)

    2009-07-15

    To evaluate the clinical, CT and MR imaging findings of semicircular canal (SCC) aplasia and to evaluate if a correlation exists between these findings and the associated anomalies or syndromes. This study retrospectively reviewed the CT and MRI findings of five patients with SCC aplasia. The CT and MR findings were analyzed for SCC, direction of facial nerve canal, cochlea, vestibule, oval or round window, middle ear ossicles, and internal auditory canal (IAC). The subjects included three boys and two girls ranging in age from one to 120 months (mean age; 51 months). Four of the subjects had the CHARGE syndrome, and one had the Goldenhar syndrome. Moreover, four subjects had sensorineural hearing loss and one had combined hearing loss. The course of the facial nerve canal was abnormal in all five cases. Moreover, trapped cochlea and dysplastic modiolus were each observed in one case. Four subjects had atresia of the oval window; whereas ankylosis of the ossicles was present in three subjects. IAC stenosis was present in one patient with the CHARGE syndrome. The aberrant course of the facial nerve canal, atresia of the oval window, and abnormal ossicles were frequently associated in patients with SCC aplasia. In addition, the Goldenhar and CHARGE syndromes were also commonly associated syndromes.

  9. Effect of canal preparation with TRUShape and Vortex rotary instruments on three-dimensional geometry of oval root canals.

    Science.gov (United States)

    Arias, Ana; Paqué, Frank; Shyn, Stephanie; Murphy, Sarah; Peters, Ove A

    2018-04-01

    The purpose of this study was to assess the geometry of non-round root canals after preparation with TRUShape (a novel instrument with s-shaped longitudinal design) in comparison to conventional rotary instrumentation using micro-computed tomography. Twenty distal root canals of mandibular molars were randomly distributed in two groups to be shaped with either TRUShape or Vortex rotaries. Percentages of unprepared surface and volume of dentin removal for the entire canal and for the apical 4 mm were calculated. Canal transportation and the structure model index (SMI) were assessed. Data were compared with Student t-tests. Shaping with both techniques resulted in similar prepared surface and volume of dentin removed, as well as the extent of canal transportation. The SMI shape factor was significantly lower for TRUShape preparations (P = 0.04) suggesting less rounding during rotary preparation. Although both instruments were suitable for the preparation of oval canals, TRUShape appeared to better conform to the original ribbon-shaped anatomy. © 2017 Australian Society of Endodontology Inc.

  10. Widespread infilling of tidal channels and navigable waterways in human-modified tidal deltaplain of southwest Bangladesh

    Directory of Open Access Journals (Sweden)

    Carol Wilson

    2017-12-01

    Full Text Available Since the 1960s, ~5000 km2 of tidal deltaplain in southwest Bangladesh has been embanked and converted to densely inhabited, agricultural islands (i.e., polders. This landscape is juxtaposed to the adjacent Sundarbans, a pristine mangrove forest, both well connected by a dense network of tidal channels that effectively convey water and sediment throughout the region. The extensive embanking in poldered areas, however, has greatly reduced the tidal prism (i.e., volume of water transported through local channels. We reveal that >600 km of these major waterways have infilled in recent decades, converting to land through enhanced sedimentation and the direct blocking of waterways by embankments and sluice gates. Nearly all of the observed closures (~98% have occurred along the embanked polder systems, with no comparable changes occurring in channels of the Sundarbans (<2% change. We attribute most of the channel infilling to the local reduction of tidal prism in poldered areas and the associated decline in current velocities. The infilled channels account for ~90 km2 of new land in the last 40–50 years, the rate of which, ~2 km2/yr, offsets the 4 km2/yr that is eroded at the coast, and is equivalent to ~20% of the new land produced naturally at the Ganges-Brahmaputra tidal rivermouth. Most of this new land, called ‘khas’ in Bengali, has been reclaimed for agriculture or aquaculture, contributing to the local economy. However, benefits are tempered by the loss of navigable waterways for commerce, transportation, and fishing, as well as the forced rerouting of tidal waters and sediments necessary to sustain this low-lying landscape against rising sea level. A more sustainable delta will require detailed knowledge of the consequences of these hydrodynamic changes to support more scientifically-grounded management of water, sediment, and tidal energy distribution.

  11. The hypoglossal canal and the origin of human vocal behavior

    Science.gov (United States)

    Kay, Richard F.; Cartmill, Matt; Balow, Michelle

    1998-01-01

    The mammalian hypoglossal canal transmits the nerve that supplies the muscles of the tongue. This canal is absolutely and relatively larger in modern humans than it is in the African apes (Pan and Gorilla). We hypothesize that the human tongue is supplied more richly with motor nerves than are those of living apes and propose that canal size in fossil hominids may provide an indication about the motor coordination of the tongue and reflect the evolution of speech and language. Canals of gracile Australopithecus, and possibly Homo habilis, fall within the range of extant Pan and are significantly smaller than those of modern Homo. The canals of Neanderthals and an early “modern” Homo sapiens (Skhul 5), as well as of African and European middle Pleistocene Homo (Kabwe and Swanscombe), fall within the range of extant Homo and are significantly larger than those of Pan troglodytes. These anatomical findings suggest that the vocal capabilities of Neanderthals were the same as those of humans today. Furthermore, the vocal abilities of Australopithecus were not advanced significantly over those of chimpanzees whereas those of Homo may have been essentially modern by at least 400,000 years ago. Thus, human vocal abilities may have appeared much earlier in time than the first archaeological evidence for symbolic behavior. PMID:9560291

  12. Viperous fangs: development and evolution of the venom canal.

    Science.gov (United States)

    Zahradnicek, Oldrich; Horacek, Ivan; Tucker, Abigail S

    2008-01-01

    Fangs are specialised long teeth that contain either a superficial groove (Gila monster, Beaded lizard, some colubrid snakes), along which the venom runs, or an enclosed canal (viperid, elapid and atractaspid), down which the venom flows inside the tooth. The fangs of viperid snakes are the most effective venom-delivery structures among vertebrates and have been the focus of scientific interests for more than 200 years. Despite this interest the questions of how the canal at the centre of the fang forms remains unresolved. Two different hypotheses have been suggested. The mainstream hypothesis claims that the venom-conducting canal develops by the invagination of the epithelial wall of the developing tooth germ. The sides of this invagination make contact and finally fuse to form the enclosed canal. The second hypothesis, known as the "brick chimney", claims the venom-conducting canal develops directly by successive dentine deposition as the tooth develops. The fang is thus built up from the tip to the base, without any folding of the tooth surface. In an attempt to cast further light on this subject the early development of the fangs was followed in a pit viper, Trimeresurus albolabris, using the expression of Sonic hedgehog (Shh). We demonstrate that the canal is indeed formed by an early folding event, resulting from an invagination of epithelial cells into the dental mesenchyme. The epithelial cells proliferate to enlarge the canal and then the cells die by apoptosis, forming an empty tube through which the poison runs. The entrance and discharge orifices at either end of the canal develop by a similar invagination but the initial width of the invagination is very different from that in the middle of the tooth, and is associated with higher proliferation. The two sides of the invaginating epithelium never come into contact, leaving the orifice open. The mechanism by which the orifices form can be likened to that observed in reptiles with an open groove along

  13. Review of root canal irrigant delivery techniques and devices

    Directory of Open Access Journals (Sweden)

    Yeon-Jee Yoo

    2011-05-01

    Full Text Available Introduction Eliminating the residual debris and bacteria in the root canal system is one of the main purposes of the endodontic treatment. However, the complexity on the anatomy of the root canal system makes it difficult to eliminate the bacterial biofilm existing along the root canal surface and necrotic pulp tissue by mechanical instrumentation and chemical irrigation. Recently, more effective irrigant delivery systems for root canal irrigation have been developed. The purpose of this review was to present an overview of root canal irrigant delivery techniques and devices available in endodontics. Review The contents of this paper include as follows; - syringe-needle irrigation, manual dynamic irrigation, brushes - sonic and ultrasonic irrigation, passive ultrasonic irrigation, rotary brush, RinsEndo, EndoVac, Laser Conclusion Though technological advances during the last decade have brought to fruition new agitation devices that rely on various mechanisms, there are few evidence based study to correlate the clinical efficacy of these devices with improved outcomes except syringe irrigation with needle and ultrasonic irrigation. The clinicians should try their best efforts to deliver antimicrobial and tissue solvent solutions in predictable volumes safely to working length.

  14. Microstructure and wettability of root canal dentine and root canal filling materials after different chemical irrigation

    Energy Technology Data Exchange (ETDEWEB)

    Antonijevic, Djordje; Milovanovic, Petar [Laboratory for Anthropology, Institute for Anatomy, Faculty of Medicine, University of Belgrade, Belgrade (Serbia); Brajkovic, Denis [Department of Dentistry, Faculty of Medical Sciences, University of Kragujevac, Kragujevac (Serbia); Ilic, Dragan [Department of Restorative Medicine, School of Dental Medicine, University of Belgrade, Belgrade (Serbia); Hahn, Michael; Amling, Michael [Department of Osteology and Biomechanics (IOBM), University Medical Center Hamburg-Eppendorf, Lottestr. 55A, 22529 Hamburg (Germany); Rakocevic, Zlatko [Laboratory for Atomic Physics, Institute for Nuclear Science “Vinca”, University of Belgrade, Belgrade (Serbia); Djuric, Marija [Laboratory for Anthropology, Institute for Anatomy, Faculty of Medicine, University of Belgrade, Belgrade (Serbia); Busse, Björn, E-mail: b.busse@uke.uni-hamburg.de [Department of Osteology and Biomechanics (IOBM), University Medical Center Hamburg-Eppendorf, Lottestr. 55A, 22529 Hamburg (Germany)

    2015-11-15

    Graphical abstract: - Highlights: • Different irrigation solutions and disinfectants were used for treatment of root canal dentine and gutta-percha points. • Materials surface characteristics were assessed using quantitative backscattered electron imaging, reference point indentation, and contact angle analyzer. • The most significant differences in mineralization, indentation, and adhesive outcomes were observed after ethylenediaminetetraacetic acid treatment. • Irrigation solutions confer to superior sealing ability of endodontic filling materials. • Micromechanical characteristics of dentine after irrigation are considerable reduced. - Abstract: The objective of this study was to determine the effects of various irrigation solutions on root canal dentine and gutta-percha surface properties. In addition, the effects of disinfectant chemicals on the wettability and surface morphological properties of the filling materials were evaluated. Ethylenediaminetetraacetic acid (EDTA), citric acid, and ozone were employed as irrigation solutions for dentine and gutta-percha treatment. Thereafter, the samples’ microstructure, degree of mineralization, and mechanical properties were assessed by means of quantitative backscattered electron imaging (qBEI) and reference point indentation (RPI). A contact angle analyzer was used to measure adhesion on the tested materials. Here, EDTA had the most significant affect on both the mechanical properties and the adhesive behavior of dentine. Citric acid did not affect dentine wettability, whereas the indentation properties and the mineralization were reduced. Similar effects were observed when ozone was used. The dentinal tubules were significantly widened in citric acid compared to the ozone group. EDTA causes considerable micromechanical surface alteration of dentine and gutta-percha, but represents the best option in clinical cases where a high adhesiveness of the filling materials is desired.

  15. Microstructure and wettability of root canal dentine and root canal filling materials after different chemical irrigation

    International Nuclear Information System (INIS)

    Antonijevic, Djordje; Milovanovic, Petar; Brajkovic, Denis; Ilic, Dragan; Hahn, Michael; Amling, Michael; Rakocevic, Zlatko; Djuric, Marija; Busse, Björn

    2015-01-01

    Graphical abstract: - Highlights: • Different irrigation solutions and disinfectants were used for treatment of root canal dentine and gutta-percha points. • Materials surface characteristics were assessed using quantitative backscattered electron imaging, reference point indentation, and contact angle analyzer. • The most significant differences in mineralization, indentation, and adhesive outcomes were observed after ethylenediaminetetraacetic acid treatment. • Irrigation solutions confer to superior sealing ability of endodontic filling materials. • Micromechanical characteristics of dentine after irrigation are considerable reduced. - Abstract: The objective of this study was to determine the effects of various irrigation solutions on root canal dentine and gutta-percha surface properties. In addition, the effects of disinfectant chemicals on the wettability and surface morphological properties of the filling materials were evaluated. Ethylenediaminetetraacetic acid (EDTA), citric acid, and ozone were employed as irrigation solutions for dentine and gutta-percha treatment. Thereafter, the samples’ microstructure, degree of mineralization, and mechanical properties were assessed by means of quantitative backscattered electron imaging (qBEI) and reference point indentation (RPI). A contact angle analyzer was used to measure adhesion on the tested materials. Here, EDTA had the most significant affect on both the mechanical properties and the adhesive behavior of dentine. Citric acid did not affect dentine wettability, whereas the indentation properties and the mineralization were reduced. Similar effects were observed when ozone was used. The dentinal tubules were significantly widened in citric acid compared to the ozone group. EDTA causes considerable micromechanical surface alteration of dentine and gutta-percha, but represents the best option in clinical cases where a high adhesiveness of the filling materials is desired.

  16. National Status and Trends: Bioeffects Program - Sabine Lake, Texas Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The toxicity of sediments in Sabine Lake, Texas, and adjoining Intracoastal Waterway canals was determined as part of bioeffects assessment studies managed by NOAA's...

  17. A comparative evaluation of the increase in root canal surface area and canal transportation in curved root canals by three rotary systems: A cone-beam computed tomographic study

    Science.gov (United States)

    Prasanthi, Nalam NVD; Rambabu, Tanikonda; Sajjan, Girija S; Varma, K Madhu; Satish, R Kalyan; Padmaja, M

    2016-01-01

    Aim: The aim of this study was to measure the increase in root canal surface area and canal transportation after biomechanical preparation at 1, 3, and 5 mm short of the apex with three different rotary systems in both continuous rotary and reciprocating rotary motions. Materials and Methods: Sixty freshly extracted human mandibular molars with mesial root canal curvatures between 20° and 30° were included in the study. Teeth were randomly distributed into three groups (n = 20). Biomechanical preparations were done in all the mesial canals. In Group 1, instrumentation was done with ProTaper universal rotary files, Group 2, with K3XF rotary files, and Group 3, with LSX rotary files. Each group was further subdivided into subgroups A and B (n = 10) where instrumentation was done by continuous rotary and reciprocating rotary techniques, respectively. Increase in root canal surface area and canal transportation was measured using the preoperative and postoperative cone-beam computed tomography scans. Statistical Analysis: The data were analyzed by one-way ANOVA followed by Tukey pairwise multiple comparison tests. Results: Increase in root canal surface area was significantly more (P 0.05) in increase of root canal surface area and canal transportation between continuous rotary and reciprocating rotary techniques for ProTaper Universal, K3XF and LSX groups. Conclusion: LSX rotary system showed minimal increase of root canal surface area and minimal canal transportation when compared to ProTaper and K3XF rotary systems. PMID:27656062

  18. Source characterization using compound composition and stable carbon isotope ratio of PAHs in sediments from lakes, harbor, and shipping waterway

    International Nuclear Information System (INIS)

    Kim, Moonkoo; Kennicutt, Mahlon C.; Qian, Yaorong

    2008-01-01

    Molecular compositions and compound specific stable carbon isotope ratios of polycyclic aromatic hydrocarbons (PAH) isolated from sediments were used to characterize possible sources of contamination at an urban lake, a harbor, a shipping waterway, and a relatively undisturbed remote lake in the northwest United States. Total PAH concentrations in urban lake sediments ranged from 66.0 to 16,500 μg g -1 dry wt. with an average of 2600 μg g -1 , which is ∼ 50, 100, and 400 times higher on average than PAH in harbor (48 μg g -1 on average), shipping waterway (26 μg g -1 ), and remote lake (7 μg g -1 ) sediments, respectively. The PAH distribution patterns, methyl phenanthrene/phenanthrene ratios, and a pyrogenic index at the sites suggest a pyrogenic origin for PAHs. Source characterization using principal component analysis and various molecular indices including C2-dibenzothiophenes/C2-phenanthrenes, C3-dibenzothiophenes/C3-phenanthrenes, and C2-chrysenes/C2-phenanthrenes ratios, was able to differentiate PAH deposited in sediments from the four sites. The uniqueness of the source of the sediment PAHs from urban lake was also illustrated by compound specific stable carbon isotope analysis. It was concluded that urban lake sediments are accumulating PAH from sources that are unique from contamination detected at nearby sites in the same watershed

  19. Characteristics of the navigational conditions and hydrotechnical infrastructure of the Upper Notec River

    Directory of Open Access Journals (Sweden)

    Grzegorz Nadolny

    2016-12-01

    Full Text Available The Upper Notec River is an important part of the waterway which is connecting Warta River and Bydgoszcz Canal. Tourist attractions are main reason for tourists visiting of the "Wielkopolska Loops". The article characterized hydrotechnical infrastructure, hydrological and depth conditions of the waterway which have an impact on the development of tourism and inland load shipping.

  20. Irrigation and crop management in Gandak Canal command of India

    International Nuclear Information System (INIS)

    Singh, S.S.; Khan, A.R.

    2002-05-01

    The Gandak Project is one of the biggest irrigation projects in India, covering a culturable command area (CCA) of 4.44 lakh ha in U.P., 9.6 lakh ha CCA in Bihar and 0.44 lakh ha in Nepal (Singh and Khan, 2002). The total culturable command areas are 14.44 lakh hectares. The command area is located in between latitude 25 deg 40' to 27 deg 25' and longitude between 83 deg 15' to 85 deg 15'. It is a diversion project through construction of a barrage on the river Gandak. This project area covers up to five districts in the Command of Tirhut Main Canal (TMC) and 3 districts in the Saran Main Canal (SMC) command. The length of main canal is usually long (990 and 650 R.D.'s in eastern and western side, respectively) and the channels are unlined and seepage loss is quite high. (author)

  1. canal24

    Data.gov (United States)

    California Natural Resource Agency — Canal system center lines in the Central Valley of California and adjacent areas captured from 1:24,000-scale USGS topographic maps. Updates and modifications made...

  2. A Mandibular Second Premolar with Three Canals and Atypical Orifices

    Directory of Open Access Journals (Sweden)

    Neha Agarwal

    2013-01-01

    Full Text Available Background: Mandibular second premolars with three canals (Type V, Vertucci and separate foramina are very rare. The anatomy of the pulp chamber floor in these premolars usually reveals one lingual and two buccal orifices at the same level. This case report describes a second premolar with three canals and an unusual pulpal floor anatomy with one mesiobuccal and one distobuccal orifice at the same level and an orifice on the distolingual wall. Very careful examination of the pulpal space with an optical device and preoperative spiral computed tomography is recommended to locate any unusual orifices.

  3. Root canal irrigants

    OpenAIRE

    Kandaswamy, Deivanayagam; Venkateshbabu, Nagendrababu

    2010-01-01

    Successful root canal therapy relies on the combination of proper instrumentation, irrigation, and obturation of the root canal. Of these three essential steps of root canal therapy, irrigation of the root canal is the most important determinant in the healing of the periapical tissues. The primary endodontic treatment goal must thus be to optimize root canal disinfection and to prevent reinfection. In this review of the literature, various irrigants and the interactions between irrigants are...

  4. Root Canal Configuration of Mandibular First and Second Premolars in an Iranian Population

    Directory of Open Access Journals (Sweden)

    Nemat Eskandarzadeh

    2007-08-01

    Full Text Available

    Background and aims. It is critical to have a proper knowledge of the normal anatomy of the pulp and its variations for the success of endodontic treatment. The aim of this study was to determine the canal configuration and the prevalence of C-shaped canals in mandibular first and second premolars in a North-Western Iranian population.

    Materials and methods. A total of 163 extracted mandibular first and 103 mandibular second premolars were injected with India ink and demineralized . They were made clear and transparent with methyl salicylate and the anatomy of their canal(s was studied.

    Results. The results showed that 98% of mandibular first premolars had one root, 2% had two roots, 70.6% had one canal, 27.8% had two canals, 1.2% had three canals and the prevalence of C-shaped canals was 2.4%. All mandibular second premolars had one root, 80.5% had one canal, 17.5% had two canals and the prevalence of C-shaped canals was 2%.

    Conclusion. It is important that clinicians, before treatment of mandibular first and second premolars, pay complete attention to radiographs, have a true concept of the number of root(s and canal(s, and prepare a correct access cavitiy.

  5. Transport and handling of dangerous goods. Training of persons in charge of vehicles or vessels carrying dangerous goods by road or by inland waterways (Dangerous Goods 1979 No.1)

    International Nuclear Information System (INIS)

    1979-01-01

    This Order supplements the Regulations of 15 April 1945 on the transport of dangerous goods by rail, land and inland waterways. It deals with the training of persons in charge of vehicles or boats carrying dangerous goods by road or by inland waterways. It refers in particular to transport of radioactive materials. (NEA) [fr

  6. Some History and Hydrology of the Panama Canal

    National Research Council Canada - National Science Library

    Pabst, Arthur

    2000-01-01

    At the request of the Panama Canal Commission (now Panama Canal Authority), the Hydrologic Engineering Center participated in the development of a model to simulate the existing operation of the Panama Canal System...

  7. THE BUSINESS OF THE CANAL: THE ECONOMICS AND POLITICS OF THE CARTER ADMINISTRATION’S PANAMA CANAL ZONE INITIATIVE, 1978

    Directory of Open Access Journals (Sweden)

    Mary C. Swilling

    2004-01-01

    Full Text Available The Carter-Torrijos Treaty of 1978, the initiative to relinquish controi of the Panama Canal Zone to the Republic of Panama, allowed Panama for the first time in its short history to become an autonomous nation and to take control of its destiny as a global trading crossroads. Conservatives rallied against President Carter and accused him of jeopardizing U. S. security and hegemony. Fears were that Panama did not have the economic or technical resources to maintain Canal operations, lacked the administrative knowledge and resources to manage the business of the Canal, lacked the military presence to insure security of the Canal, and did not have the political and social will to maintain the environmental integrity of the region. In short, disastrous results were predicted. Carter prevailed. December 31, 1999 saw the surrender of the Canal Zone, and all its facilities, to Panama. This paper discusses events that precipitated Carter’s decision, economic and political arguments presented during the 1977-78 debate, implementation of the treaty, and an evaluation of the ‘business of the Canal’ today.

  8. Radiographic Localization of the Mental Foramen and Mandibular Canal

    Directory of Open Access Journals (Sweden)

    Farzaneh Afkhami

    2013-01-01

    Full Text Available Objective: Accurately localizing the mental foramen and mandibular canal is important when administering local anesthesia and performing surgery; therefore, knowing the normal range of the possible locations is essential. Our purpose was to assess the location of the mental foramen and mandibular canal in an Iranian population using panoramic radiography.Materials and Methods: Standard panoramic radiographies were performed. The positions of 100 mental foramens were evaluated. The distances from the center of the mental foramen to the superior and inferior borders of the mandible and to the apexes of the first and second premolar were measured. The distance of the mental foramens from the mandibular midline and the diameter of the mandibular canal in the mental foramen connection were also measured.Results: Among 100 mental foramens, 6% were positioned under the first premolar, 24% were between the first and second premolars, 67% were under the second premolar, and the remaining 3% were behind the second premolar. The mean distance from the mental foramen to the mandibular midline was 27.77±3.20 mm. The mean diameter of the mandibular canal in the mental foramen connection was 3.09±0.69mm.Conclusion: The mental foramen was near the second premolar and the inferior border of the mandible. This information can be used to perform safer mental nerve blocks in surgical interventions.

  9. 33 CFR 162.175 - Black Rock Canal and Lock at Buffalo, New York.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Black Rock Canal and Lock at Buffalo, New York. 162.175 Section 162.175 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF... Black Rock Canal and Lock at Buffalo, New York. In the Black Rock Canal and Lock, no vessel may exceed 6...

  10. Lightlike Hypersurfaces and Canal Hypersurfaces of Lorentzian Surfaces

    Directory of Open Access Journals (Sweden)

    Jianguo Sun

    2014-01-01

    Full Text Available The lightlike hypersurfaces in semi-Euclidean space are of special interest in Relativity Theory. In particular, the singularities of these lightlike hypersurfaces provide good models for the study of different horizon types. And we obtain some geometrical propositions of the canal hypersurfaces of Lorentzian surfaces. We introduce the notions of flatness for these hypersurfaces and study their singularities.

  11. Independent and Confluent Middle Mesial Root Canals in Mandibular First Molars: A Report of Four Cases

    Directory of Open Access Journals (Sweden)

    Mohanavelu Deepalakshmi

    2012-01-01

    Full Text Available Mandibular molars demonstrate considerable variations with respect to number of roots and root canals. The possibility of additional root canals should be considered even in teeth with a low frequency of abnormal root canal anatomy. This paper discusses the endodontic management of the rare anatomical complexity middle mesial canals in mandibular first molar and also serves to remind the clinicians that such anatomical variations should be taken into account during the endodontic treatment of the mandibular molars.

  12. The osseous external auditory canal : Surgery, shape, and sound

    NARCIS (Netherlands)

    van Spronsen, E.

    2018-01-01

    This thesis describes three aspects of the osseous external auditory canal (OEAC) which are related to each other: Surgery of the OEAC, the shape of the OEAC and the perceived sound quality due to the resonance function of the OEAC. Several aspects of the surgical intervention (Canalplasty) in

  13. Closure of the vertebral canal in human embryos and fetuses

    NARCIS (Netherlands)

    Mekonen, Hayelom K.; Hikspoors, Jill P. J. M.; Mommen, Greet; Kruepunga, Nutmethee; Köhler, S. Eleonore; Lamers, Wouter H.

    2017-01-01

    The vertebral column is the paradigm of the metameric architecture of the vertebrate body. Because the number of somites is a convenient parameter to stage early human embryos, we explored whether the closure of the vertebral canal could be used similarly for staging embryos between 7 and 10weeks of

  14. Measurement and visualization of file-to-wall contact during ultrasonically activated irrigation in simulated canals

    NARCIS (Netherlands)

    Boutsioukis, C.; Verhaagen, B.; Walmsley, A.D.; Versluis, Michel; van der Sluis, L.W.M.

    2013-01-01

    Aim (i) To quantify in a simulated root canal model the file-to-wall contact during ultrasonic activation of an irrigant and to evaluate the effect of root canal size, file insertion depth, ultrasonic power, root canal level and previous training, (ii) To investigate the effect of file-to-wall

  15. Towpaths to Oblivion. The Middlesex Canal and the Coming of the Railroad 1792-1853.

    Science.gov (United States)

    Holmes, Cary W.

    This narrative history of the Middlesex Canal from 1792-1853 is designed to be used with "Canal," a role-playing, decision-making game found in SO 011 886. Economic, social, and political factors related to planning, building, and implementing the canal are considered. The document is presented in three parts. Part I states reasons for…

  16. Endodontic Treatment of a Mandibular Second Premolar with Three Roots and Three Canals

    Directory of Open Access Journals (Sweden)

    Bonny Paul

    2014-01-01

    Full Text Available Complex root canal system with atypical variations is a common finding among mandibular premolars. Endodontic treatment in these teeth may not be successful due to the failure to recognise and treat multiple canals. This paper presents endodontic treatment of a mandibular second premolar with three roots and three canals.

  17. Measurement and visualization of file-to-wall contact during ultrasonically activated irrigation in simulated canals

    NARCIS (Netherlands)

    Boutsioukis, C.; Verhaagen, B.; Walmsley, A. D.; Versluis, M.; van der Sluis, L. W. M.

    2013-01-01

    Aim(i) To quantify in a simulated root canal model the file-to-wall contact during ultrasonic activation of an irrigant and to evaluate the effect of root canal size, file insertion depth, ultrasonic power, root canal level and previous training, (ii) To investigate the effect of file-to-wall

  18. Effect of Instrument Design and Access Outlines on the Removal of Root Canal Obturation Materials in Oval-shaped Canals.

    Science.gov (United States)

    Niemi, Tuomas K; Marchesan, Melissa A; Lloyd, Adam; Seltzer, Robert J

    2016-10-01

    The aim of this study was to compare the effectiveness of TRUShape (TS) instruments with ProFile Vortex Blue (VB) instruments for the removal of obturation materials during retreatment of single-canal mandibular premolars performed through 2 access outlines. Initial root canal treatment was completed through a contracted endodontic cavity (CEC) design. Canals were instrumented to an F2 ProTaper instrument, obturated with warm lateral condensation of gutta-percha with AH Plus sealer, and allowed to set for 30 days at 37°C and 100% humidity. For retreatment, specimens were divided into 2 groups (n = 24) on the basis of access outline, CEC or traditional endodontic cavity (TEC). Retreatment was initiated by using ProTaper Retreatment instruments (D1-D3). Specimens were then stratified, further divided (n = 12), and reinstrumented up to TS 40 .06v or 40 .06 VB. Irrigation was performed by using 8.25% NaOCl and QMix 2in1. Retreatment time was recorded. Teeth were sectioned and photographed, and the percentage of remaining obturation materials was measured. Data were analyzed with Kruskal-Wallis analysis of variance for two-factor tests (α canal surface when compared with TEC-VB, CEC-TS, and TEC-TS (P ≤ .05). None of these other combinations were different from each other (P > .05). Significantly more time was required for retreatment with CEC-TS (27.68 ± 1.4 minutes) than the other groups (P root canal surface of mandibular premolars. However, in the presence of a CEC access design, using TS instruments removed more obturating material in single-rooted, oval-shaped canals. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  19. Spatial and seasonal variations of the contamination within water body of the Grand Canal, China

    NARCIS (Netherlands)

    Wang, X.L.; Han, Jingyi; Xu, L.G.; Zhang, Q.

    2010-01-01

    To delineate the character of contaminations in the Grand Canal, China, a three-year study (2004-2006) was conducted to investigate variations the water quality in the canal. Results showed that the variation of water quality within the Grand Canal was of there is remarkable spatial and seasonal

  20. Waterborne Commerce of the United States, Calendar Year 1986. Part 1. Waterways and Harbors, Atlantic Coast

    Science.gov (United States)

    1988-05-31

    AHARfl THENCE IN DECEMBER 1996, 16.9 FEET ToI LOSDELL CANAL, I.? -ILES; THENCE IN MAY 1984, 11.3 FEET TO MARKET STREET BRIDGE AT WIL4149TON, ?.1 MILES...389,252 FREIGHT TRAFFIC, 1986 OCEANGnING (SHORT TONS) FOREIGN DOMESTIC COASToIsE COM4OO TY TOTAL IMPORTS ESPORTS RECEIPTS SHIPMENTS TOTAL

  1. Root anatomy and canal configuration of the permanent mandibular first molar: a systematic review.

    Science.gov (United States)

    de Pablo, Oliver Valencia; Estevez, Roberto; Péix Sánchez, Manuel; Heilborn, Carlos; Cohenca, Nestor

    2010-12-01

    The main goal of endodontic therapy is to prevent or heal apical periodontitis. However, root canal anatomy might present a clinical challenge directly related to the treatment outcome. The purpose of this study was to review published literature related to root anatomy and root canal configuration of the permanent mandibular first molar. An exhaustive search was undertaken to identify published literature related to the root anatomy and root canal morphology of the permanent mandibular first molar by using key words. The search of the MEDLINE database included all publications from 1966-May 2010. Selected articles were then obtained and reviewed. Data evaluated and summarized in the data sheet included methodology, population, number of teeth per study (power), number of root canals, type of root canal configuration, and identification of number of apical foramina. Forty-one studies were identified including a total of 18,781 teeth. The incidence of a third root was 13% and was strongly correlated with the ethnicity of the studied population. Three canals were present in 61.3%, 4 canals in 35.7%, and 5 canals in approximately 1%. Root canal configuration of the mesial root revealed 2 canals in 94.4% and 3 canals in 2.3%. The most common canal system configuration was Vertucci type IV (52.3%), followed by type II (35%). Root canal configuration of the distal root revealed type I configuration in 62.7%, followed by types II (14.5%) and IV (12.4%). The presence of isthmus communications averaged 54.8% on the mesial and 20.2% on the distal root. The number of roots on the mandibular first molar is directly related to ethnicity. Root canal morphology and configuration might present the clinician with a complex anatomy requiring more diagnostic approaches, access modifications, and clinical skills to successfully localize, negotiate, disinfect, and seal the root canal system. Crown Copyright © 2010. Published by Elsevier Inc. All rights reserved.

  2. Chemical concentrations in water and suspended sediment, Green River to Lower Duwamish Waterway near Seattle, Washington, 2016–17

    Science.gov (United States)

    Conn, Kathleen E.; Black, Robert W.; Peterson, Norman T.; Senter, Craig A.; Chapman, Elena A.

    2018-01-05

    From August 2016 to March 2017, the U.S. Geological Survey (USGS) collected representative samples of filtered and unfiltered water and suspended sediment (including the colloidal fraction) at USGS streamgage 12113390 (Duwamish River at Golf Course, at Tukwila, Washington) during 13 periods of differing flow conditions. Samples were analyzed by Washington-State-accredited laboratories for a large suite of compounds, including metals, dioxins/furans, semivolatile compounds including polycyclic aromatic hydrocarbons, butyltins, the 209 polychlorinated biphenyl (PCB) congeners, and total and dissolved organic carbon. Concurrent with the chemistry sampling, water-quality field parameters were measured, and representative water samples were collected and analyzed for river suspended-sediment concentration and particle-size distribution. The results provide new data that can be used to estimate sediment and chemical loads transported by the Green River to the Lower Duwamish Waterway.

  3. OPG waterways public safety program

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, T [Ontario Power Generation Inc., Niagara Falls, ON (Canada)

    2009-07-01

    Ontario Power Generation (OPG) has 64 hydroelectric generating stations, 241 dams, and 109 dams in Ontario's registry with the International Commission on Large Dams (ICOLD). In 1986, it launched a formal dam safety program. This presentation addressed the importance of public safety around dams. The safety measures are timely because of increasing public interaction around dams; the public's unawareness of hazards; public interest in extreme sports; easier access by recreational vehicles; the perceived right of public to access sites; and the remote operation of hydroelectric stations. The presentation outlined the OPG managed system approach, with particular reference to governance; principles; standards and procedures; and aspects of implementation. Specific guidelines and governing documents for public safety around dams were identified, including guidelines for public safety of waterways; booms and buoys; audible warning devices and lights; public safety signage; fencing and barricades; and risk assessment for public safety around waterways. The presentation concluded with a discussion of audits and management reviews to determine if safety objectives and targets have been met. figs.

  4. Adaptation and penetration of resin-based root canal sealers in root canals irradiated with high-intensity lasers

    Science.gov (United States)

    Moura-Netto, Cacio; Mello-Moura, Anna Carolina Volpi; Palo, Renato Miotto; Prokopowitsch, Igor; Pameijer, Cornelis H.; Marques, Marcia Martins

    2015-03-01

    This research analyzed the quality of resin-based sealer adaptation after intracanal laser irradiation. Extracted teeth (n=168) were root canal treated and divided into four groups, according to dentin surface treatment: no laser; Nd:YAG laser (1.5 W, 100 mJ, 15 Hz) diode laser (2.5 W in CW), and Er:YAG laser (1 W, 100 mJ, 10 Hz). The teeth were divided into four subgroups according to the sealer used: AH Plus, EndoREZ, Epiphany, and EpiphanySE. For testing the sealing after root canal obturation, the penetration of silver nitrate solution was measured, whereas to evaluate the adaptation and penetration of the sealer into the dentin, environmental scanning electron microscopy (ESEM) was used. The ESEM images were analyzed using a four-grade criteria score by three evaluators. The inter-examiner agreement was confirmed by Kappa test and the scores statistically compared by the Kruskal-Wallis' test (p<0.05). Both adaptation and sealer penetration in root canals were not affected by the laser irradiation. Nd:YAG and diode laser decreased the tracer penetration for AH Plus, whereas EndoREZ and EpiphanySE performances were affected by Nd:YAG irradiation (p<0.05). It can be concluded that intracanal laser irradiation can be used as an adjunct in endodontic treatment; however, the use of hydrophilic resin sealers should be avoided when root canals were irradiated with Nd:YAG laser.

  5. The width of the incisive canal and labial alveolar bone of the incisive canal: an assessment on CT images

    International Nuclear Information System (INIS)

    Roh, Yang Gyun; Jang, Hyun Seon; Kim, Byung Ock; Kim, Jin Soo

    2006-01-01

    To assess the width of the labial alveolar bone of the incisive canal and the width of the incisive canal on spiral computed tomographic images of the anterior portion of the maxilla. Study materials included 38 CT scans taken for preoperative planning of implant placement. Axial cross-sectioned image entirely showing the incisive canal at an orifice to the oral cavity, middle portion, and an orifice to the nasal cavity and the diameter of the incisive canal at the middle portion were determined by two specialist using Digora for Windows 2.1. The statistical analyses were carried out using SPSS 12.0.1. When the maxillary central incisors remained, the mean labial alveolar bone width were 6.81±1.41 mm, 6.46±1.33 mm, and 7.91±1.33 mm. When the maxillary central incisors were missed the mean width were 5.42±2.20 mm, 6.23±2.29 mm, and 7.89±2.13 mm. The labial alveolar bone width at middle portion and an orifice to the nasal cavity were of no statistical significant difference according to presence of the maxillary central incisors (P>0.05). The width between oral cavity and nasal cavity, middle portion and to masal cavity revealed statistically significant difference (P<0.05)

  6. First Branchial Cleft Fistula Associated with External Auditory Canal Stenosis and Middle Ear Cholesteatoma

    Directory of Open Access Journals (Sweden)

    shahin abdollahi fakhim

    2014-10-01

    Full Text Available Introduction: First branchial cleft anomalies manifest with duplication of the external auditory canal.   Case Report: This report features a rare case of microtia and congenital middle ear and canal cholesteatoma with first branchial fistula. External auditory canal stenosis was complicated by middle ear and external canal cholesteatoma, but branchial fistula, opening in the zygomatic root and a sinus in the helical root, may explain this feature. A canal wall down mastoidectomy with canaloplasty and wide meatoplasty was performed. The branchial cleft was excised through parotidectomy and facial nerve dissection.   Conclusion:  It should be considered that canal stenosis in such cases can induce cholesteatoma formation in the auditory canal and middle ear.

  7. Unusual root canal morphology of mandibular second premolars: A case series and review

    Directory of Open Access Journals (Sweden)

    Snehal Sonarkar

    2017-01-01

    Full Text Available Mandibular second premolars (MSPs have varied anatomy ranging from 1 to 3 roots and 1–5 canals. Successful endodontic treatment is achieved by proper access opening, cleaning, and shaping and three-dimensional obturation. This case series describes five cases in which MSPs have been diagnosed with aberrant canal system. The Case 1 and 5 has one root with Vertucci's Type V canal configuration. The Case 2 has two roots with two canals, the Case 3 has one root with Vertucci's Type IV canal configuration, whereas the Case 4 has three roots with three canals. This case series also describes a classification for describing the root configuration. The clinical implications of this paper are first to reach at appropriate diagnosis of canal system using diagnostic aids (angulated radiographs and dental operating microscope. Second, to use advanced endodontic instruments for achieving successful endodontic therapy (NiTi rotary instruments.

  8. Prevalence of the middle mesial canal in non surgical root canal treated mandibular first and second molars in a local military population

    Science.gov (United States)

    2016-06-13

    or second mandibular molar), sex, and age. Materials and Methods Approximately 7, 000 dental records in paper chart format were reviewed at a...Army Post Graduate Dental School Douglas D. Lancaster, COL, DC 3 August 2016 Prevalence of the middle mesial canal in non-surgical root canal...Methods: 7000 dental records were reviewed for non-surgical root canals performed from October 1970 to October 2015. The data collected included

  9. Assessment of bifid and trified mandicular canals using cone beam computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Rashsyren, Oyuntugs [Dept. of Oral and Maxillofacial Radiology, School of Dentistry, Mongolian National University Medical Science, Ulaanbaatar (United States); Choi, Jin Woo; Han, Won Jeong; Kim Eun Kyung [Dept. of Oral and Maxillofacial Radiology, Dankook University College of Dentistry, Cheonan (Korea, Republic of)

    2014-09-15

    To investigate the prevalence of bifid and trifid mandibular canals using cone-beam computed tomography (CBCT) images, and to measure their length, diameter, and angle. CBCT images of 500 patients, involving 755 hemi-mandibles, were used for this study. The presence and type of bifid mandibular canal was evaluated according to a modified classification of Naitoh et al. Prevalence rates were determined according to age group, gender, and type. Further, their diameter, length, and angles were measured using PACSPLUS Viewer and ImageJ 1.46r. Statistical analysis with chi-squared and analysis of variance (ANOVA) tests was performed. Bifid and trifid mandibular canals were found in 22.6% of the 500 patients and 16.2% of the 755 sides. There was no significant difference between genders and among age groups. The retromolar canal type accounted for 71.3% of the identified canals; the dental canal type, 18.8%; the forward canal type, 4.1%; and the trifid canal type, 5.8%. Interestingly, seven cases of the trifid canal type, which has been rarely reported, were observed. The mean diameter of the bifid and trifid mandibular canals was 2.2 mm and that of the main mandibular canal was 4.3 mm. Their mean length was 16.9 mm; the mean superior angle was 149.2 degrees, and the mean inferior angle was 37.7 degrees. Bifid and trifid mandibular canals in the Korean population were observed at a relatively high rate through a CBCT evaluation, and the most common type was the retromolar canal. CBCT is suggested for a detailed evaluation of bifid and trifid mandibular canals before mandibular surgery.

  10. Waterborne Commerce of the United States Calendar Year 1987. Part 4. Waterways and Harbors Pacific Coast, Alaska and Hawaii

    Science.gov (United States)

    1989-05-31

    AND UNAR OR DRY CARGO TANKER AN TASER DRY CARGO TUGBOAT DR CARGO RUGASO SK3G4 AY IARBOR, ALASKA..(CONTINJED) INJ8IJJND OJTBOJND 25...122 Colombia River Entrance, Oreg., and Lewis River, Wash. ---- 59, 119 Wash. ------------ 40, 115 Long Beach Harbor, Calif. ,----- 4 105...6, 105 Colombia Rsver, Portn other than Portland, Lynn Canal, blask--------5. 128 Astoria, St. Helens, Longvien, Vanvoover, and Kala -------- 4

  11. Magnetic resonance tomography of the vertebral column and spinal canal

    International Nuclear Information System (INIS)

    Uhlenbrock, D.; Brueckmann, H.; Bunke, J.; Giesecke, J.; Heinzerling, J.; Kunze, V.; Mirvis, S.E.; Weidner, A.; Wolf, A.L.

    1992-01-01

    In addition to all the aspects pertinent to diagnostic procedures in the vertebral column and spinal canal this pocket book provides complete coverage of congenital and acquired disorders in the fields of orthopedics, neurology and neurosurgery - including malformations of the spinal canal, degenerative vertebral diseases, tumours, inflammatory changes and vascular diseases, to mention only a few. The authors discuss the question of how image qualities can be influenced and the most information obtained from the different pulse sequences. They outline future development trends and give advice on the reduction of artefacts. The principles that must be adhered to in surgical intervention and nmr imaging for the post-operative assessment of vertebral disk syndromes and tumours are just as important an issue here as is the information the surgeon expects to obtain through diagnostic nmr imaging and the recommendations to be given by the radiologist. (orig.) With 265 figs [de

  12. The Nicaragua Canal:Security And Economic Boom Or Bust

    Science.gov (United States)

    2014-04-01

    supporting. Today, Nicaraguan President Daniel Ortega intends to finish what Louis- Napoleon Bonaparte ( Napoleon III) started in 1846 and build a canal...sought a maritime route across Central America, connecting the Atlantic and Pacific Oceans, for trade purposes. Louis- Napoleon Bonaparte and his...French government (along with the British government before Napoleon became President, then Emperor of France) tried three separate times in the early

  13. Environmental Characterization and Radioecological Assessment of Suez Canal Area, Egypt

    International Nuclear Information System (INIS)

    Ramadan, A.A.; Zaki, A.H.; Diab, M.; Al-Ashry, KH.A.M.

    2015-01-01

    The present study was conducted to investigate the environmental characteristic and radioecological assessment of the Suez Canal area, Egypt. The hydrochemical parameters including major elements (Ca, Mg, Na, Cl, SO 4 , HCO 3 ) and trace elements (Zn, Pb, Fe, Cu, Cd) of the soil, plant and water samples collected from the Suez Canal area were measured. The natural radioactivity and man-made radionuclides were measured in the same samples.The specific activities of 238 U series, 232 Th series, 40 K and 137 Cs (Bq/kg dry weight) were measured using gamma ray spectrometers based on hyper pure germanium detectors. The absorbed radiation dose rates in air (nGy/h) due to natural radionuclides in soil, and radium equivalent activity index (Bq/kg) were calculated. The average specific activity of 238 U series, 232 Th series and 40 K in soil samples were 12.9, 10.2 and 144.9 Bq/kg, respectively. The activity concentrations of 137 Cs in the different collected samples and 238 U and 232 Th series in plant and water samples were less than the lower detection limit. The average specific activity of 40 K in plant samples was 325.8 Bq/kg. The concentration and distribution pattern of 238 U series in soil can be used to trace the radiological impact of the non-nuclear industries on the Suez Canal area.

  14. Usefulness and limitations of neuroradiological examinations in lumbar canal stenosis

    International Nuclear Information System (INIS)

    Nishi, Shogo; Hanakita, Junya; Suwa, Hideyuki; Ohta, Fumito; Sakaida, Hiroshi

    1989-01-01

    Since 1983, we have performed 434 spinal surgery operations. Among them are included 51 cases of lumbar canal stenosis. For these 51 cases, we performed several neuroradiological examinations, such as lumbar plain X-ray, myelography, metrizamide-CT scan (Met-CT) and magnetic resonance imaging (MRI). On myelography, these 51 patients were divided into three types; a complete block type with 29 patients, soy-beans type with 7 patients and strangulation type with 15 patients. Met CT was performed in 37 cases. In both strangulation type and soy-beans type which had been showed through myelography, Met-CT could clearly demonstrate the subarachnoid space, and several structures around the lumbar spinal canal could be clearly identified. In cases which myelography revealed as complete-block type, we identified two subtypes. In the first type subarachnoid space was clearly demonstrated by Met-CT. The second type was comprised of those cases where Met-CT scan could not demonstrate subarachnoid space at all. MRI was performed on 21 patients. MRI clearly showed the anatomical relationship of disc, subarachnoid space, yellow ligament and hypertrophied bony structure. MRI was thus able to bring useful information about lumbar canal stenosis even in cases where Met-CT gave little information due to the lack of metrizamide penetration of the stenotic subarachnoid space. (J.P.N.)

  15. Shaping ability of NT Engine and McXim rotary nickel-titanium instruments in simulated root canals. Part 1.

    Science.gov (United States)

    Thompson, S A; Dummer, P M

    1997-07-01

    The aim of this study was to determine the shaping ability of NT Engine and McXim nickel-titanium rotary instruments in simulated root canals. In all, 40 canals consisting of four different shapes in terms of angle and position of curvature were prepared by a combination of NT Engine and McXim instruments using the technique recommended by the manufacturer. Part 1 of this two-part report describes the efficacy of the instruments in terms of preparation time, instrument failure, canal blockages, loss of canal length and three-dimensional canal form. Overall, the mean preparation time for all canals was 6.01 min, with canal shape having a significant effect (P Engine and McXim instruments prepared canals rapidly, with few deformations, no canal blockages and with minimal change in working length. The three-dimensional form of the canals demonstrated good flow and taper characteristics.

  16. Direct and CT measurements of canals and foramina of the skull base

    International Nuclear Information System (INIS)

    Berlis, A.; Schumacher, M.; Putz, R.

    1992-01-01

    This investigation is based on measurements of 60 macerated adult European skulls from the Alexander-Ecker Collection at the Anatomy Department of the University of Freiburg. Computer tomographical (CT) and anatomical measurements were compared to assess the accuracy of the CT representation of osseous structures. Nine structures were examined: the optic canal, superior orbital fissure, foramen rotundum, foramen ovale, foramen spinosum,foramen Vesalii (venosum), carotid canal, internal auditory canal and hypoglossal canal. Results show a good and even excellent correlation if the cranial opening is approximately at a right angle to the scanline. For this reason, the results of the coronal examination of the internal auditory canal are less satisfactory, and the coronal and axial measurements of the hypoglossal canal show only a moderately good correlation. (author)

  17. C-SHAPED CONFIGURATION OF THE ROOT CANAL SYSTEM – PROBLEMS AND SOLUTIONS.

    Directory of Open Access Journals (Sweden)

    Janet Kirilova

    2014-06-01

    Full Text Available Introduction: The patients with C-shaped configuration of the root canal system are definitely a problem in the everyday dental practice. The C-shaped configuration of the root canal can be seen in the mandibular and maxillary molars. The treatment of these teeth is very difficult. Purpose: To trace the treatment of clinical cases with C-shaped configuration of the root canal system. Material and methods: There are some different cases that are described with a C-shaped configuration of the root canal system with one, two, three and four separate root canals. Careful exploration of the floor of the pulp chamber, inspection with magnification, use of ultrasonic irrigation and a modified filling technique are of particular use. Results and Discussion: Clinical cases of a C-shaped pulp chamber and root canal system shows that this root canal aberration occurs in a wide variety and variability with a single root canal up to two, three and four separate root canals. The diameter of the root canal themselves also varies from very wide to such with a small diameter. Conclusions: Knowledge of the different anatomical variations will improve the endododntic practice of the general dental practitioners.

  18. Comparison among manual instruments and PathFile and Mtwo rotary instruments to create a glide path in the root canal preparation of curved canals.

    Science.gov (United States)

    Alves, Vanessa de Oliveira; Bueno, Carlos Eduardo da Silveira; Cunha, Rodrigo Sanches; Pinheiro, Sérgio Luiz; Fontana, Carlos Eduardo; de Martin, Alexandre Sigrist

    2012-01-01

    Nickel-titanium rotary instruments reduce procedural errors and the time required to finish root canal preparation. The goal of this study was to evaluate the occurrences of apical transportation and canal aberrations produced with different instruments used to create a glide path in the preparation of curved root canals, namely manual K-files (Dentsply Maillefer, Ballaigues, Switzerland) and PathFile (Dentsply Maillefer) and Mtwo (Sweden and Martina, Padua, Italy) nickel-titanium rotary files. The mesial canals of 45 mandibular first and second molars (with curvature angles between 25° and 35°) were selected for this study. The specimens were divided randomly into 3 groups with 15 canals each, and canal preparation was performed by an endodontist using #10-15-20 K-type stainless steel manual files (group M), #13-16-19 PathFile rotary instruments (group PF), and #10-15-20 Mtwo rotary instruments (group MT). The double digital radiograph technique was used, pre- and postinstrumentation, to assess whether apical transportation and/or aberration in root canal morphology occurred. The initial and final images of the central axis of the canals were compared by superimposition through computerized analysis and with the aid of magnification. The specimens were analyzed by 3 evaluators, whose calibration was checked using the Kendall agreement test. No apical transportation or aberration in root canal morphology occurred in any of the teeth; therefore, no statistical analysis was conducted. Neither the manual instruments nor the PathFile or Mtwo rotary instruments used to create a glide path had any influence on the occurrence of apical transportation or produced any canal aberration. Copyright © 2012 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  19. Cone-beam computed tomography study of root and canal morphology of mandibular premolars in a western Chinese population

    International Nuclear Information System (INIS)

    Yu, Xuan; Guo, Bin; Li, Ke-Zeng; Zhang, Ru; Tian, Yuan-Yuan; Wang, Hu; DDS, Tao Hu

    2012-01-01

    Traditional radiography is limited in its ability to give reliable information on the number and morphology of root canals. The application of cone-beam computed tomography (CBCT) provides a non-invasive three-dimensional confirmatory diagnosis as a complement to conventional radiography. The aim of this study was to evaluate the root and canal morphology of mandibular premolars in a western Chinese population using CBCT scanning. The sample included 149 CBCT images comprising 178 mandibular first premolars and 178 second premolars. The tooth position, number of roots and canals, and canal configuration according to Vertucci’s classification were recorded. The results showed that 98% of mandibular first premolars had one root and 2% had two roots; 87.1% had one canal, 11.2% had two canals and 0.6% had three canals. The prevalence of C-shaped canals was 1.1%. All mandibular second premolars had one root; 97.2% had one canal and 2.2% had two canals. The prevalence of C-shaped canals was 0.6%. The prevalence of multiple canals in mandibular first premolars was mainly of Type V, and mandibular second premolars had a low rate of canal variation in this western Chinese population. Root canal bifurcation occurred at the middle or apical third in most bicanal mandibular premolars. CBCT scanning can be used in the management of mandibular premolars with complex canal morphology

  20. OPG - Waterways public safety program

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, Tony [Ontario Power Generation (Canada)

    2011-07-01

    Ontario Power Generation (OPG) operates 65 hydroelectric generating stations in Ontario and has 241 dams. Security around dams is an important matter to minimize exposure of the public to hazards and to prevent an uncontrolled release of water and also to be prepared in case of failure. The purpose of this presentation is to describe the waterways public safety program developed by OPG in association with the Ontario Waterpower Associattion, the Canadian Dam Association and the Ontario Ministry of Natural Resoruces. This program takes a managed system approach with continuous review to address specific and changing conditions of sites. Policies, accountability mechanisms and assessments are first planned, and then implemented, every day functioning is monitored, corrective actions are developed on the basis of issues and reports are compiled for planning of new improvements. This research program provided OPG with new methods for preventing accidents more efficiently.

  1. 76 FR 8653 - Drawbridge Operation Regulation; Gulf Intracoastal Waterway, New Orleans Harbor, Inner Harbor...

    Science.gov (United States)

    2011-02-15

    ... Operation Regulation; Gulf Intracoastal Waterway, New Orleans Harbor, Inner Harbor Navigation Canal, New Orleans, Orleans Parish, LA AGENCY: Coast Guard, DHS. ACTION: Notice of temporary deviation from... Lock), at New Orleans, Orleans Parish, Louisiana. This deviation is necessary to replace all of the...

  2. 75 FR 78601 - Drawbridge Operation Regulation; Gulf Intracoastal Waterway, New Orleans Harbor, Inner Harbor...

    Science.gov (United States)

    2010-12-16

    ... Operation Regulation; Gulf Intracoastal Waterway, New Orleans Harbor, Inner Harbor Navigation Canal, New Orleans, Orleans Parish, LA AGENCY: Coast Guard, DHS. ACTION: Notice of temporary deviation from... Harvey Lock), at New Orleans, Orleans Parish, Louisiana. This deviation is necessary to adjust the...

  3. A new anatomically based nomenclature for the roots and root canals-part 1: maxillary molars.

    Science.gov (United States)

    Kottoor, Jojo; Albuquerque, Denzil Valerian; Velmurugan, Natanasabapathy

    2012-01-01

    Numerous terminologies have been employed in the dental literature to describe the roots and root canal systems of maxillary molars. This multiplicity in naming of roots and canals makes the reader susceptible to misinterpretation and confusion. No consensus thus far has been arrived at for defining the names of roots and root canals in maxillary molars, including their various morphological aberrations. The anatomical relation of roots and their root canals were identified and were subsequently named based on definite sets of criteria. A new method for identification and naming of roots and root canal anatomy in maxillary molars, based on their root and canal relationship, was formulated and is presented in this paper. The nomenclature makes certain essential modifications to the traditional approach to accommodate naming of the various aberrations presented in the maxillary molars. A simple, yet extensive, nomenclature system has been proposed that appropriately names the internal and external morphology of maxillary molars.

  4. NMR imaging of the vertebral column and the spinal canal. 2. rev. and enl. ed.; MRT der Wirbelsaeule und des Spinalkanals

    Energy Technology Data Exchange (ETDEWEB)

    Forsting, Michael [Universitaetsklinikum Essen (Germany). Inst. fuer Diagnostische und Interventionelle Radiologie und Neuroradiologie; Uhlenbrock, Detlev [St.-Josefs-Hospital, Dortmund (Germany). MVZ Radiologie, Nuklearmedizin und Strahlentherapie; Wanke, Isabel [Privatklinikengruppe Hirslanden, Zurich (Switzerland); Universitaetsklinikum Essen (Germany). Inst. fuer Diagnostische und Interventionelle Radiologie und Neuroradiologie

    2009-07-01

    The book on the MRT (magnetic resonance tomography) of the vertebral cord and spinal canal covers the following topics: physics fundamentals and application; malformation of the spinal canal; degenerative vertebral column diseases; vertebral column and spinal canal carcinomas; inflammatory diseases of the vertebral column and the spinal canal; applicability of MRT in case of acute spinal cord traumata; vascular diseases of the spinal canal.

  5. A quantitative analysis of rotary, ultrasonic and manual techniques to treat proximally flattened root canals

    Directory of Open Access Journals (Sweden)

    Fabiana Soares Grecca

    2007-04-01

    Full Text Available OBJECTIVE: The efficiency of rotary, manual and ultrasonic root canal instrumentation techniques was investigated in proximally flattened root canals. MATERIAL AND METHODS: Forty human mandibular left and right central incisors, lateral incisors and premolars were used. The pulp tissue was removed and the root canals were filled with red die. Teeth were instrumented using three techniques: (i K3 and ProTaper rotary systems; (ii ultrasonic crown-down technique; and (iii progressive manual technique. Roots were bisected longitudinally in a buccolingual direction. The instrumented canal walls were digitally captured and the images obtained were analyzed using the Sigma Scan software. Canal walls were evaluated for total canal wall area versus non-instrumented area on which dye remained. RESULTS: No statistically significant difference was found between the instrumentation techniques studied (p<0.05. CONCLUSION: The findings of this study showed that no instrumentation technique was 100% efficient to remove the dye.

  6. Genetic and life-history trait variation of the amphipod Melita plumulosa from polluted and unpolluted waterways in eastern Australia

    International Nuclear Information System (INIS)

    Chung, Pann Pann; Hyne, Ross V.; Mann, Reinier M.; Ballard, J. William O.

    2008-01-01

    To monitor genetic diversity and environmental contamination in eastern Australia, toxicity studies have employed the sensitive benthic amphipod Melita plumulosa. The goal of this study was to examine the genetic and life-history variability of natural populations of M. plumulosa from the Parramatta (polluted) and Hawkesbury (unpolluted) Rivers. The underlying genetics of the populations in these distinct waterways was examined at one mitochondrial (cytochrome c oxidase subunit I (COI)) and one nuclear (ribosomal internal transcribed spacer region 1 (ITS1)) locus. Seven unique haplotypes for COI were found amongst animals from the Parramatta River, while animals from the Hawkesbury River showed a complete absence of genetic variation at this locus. At ITS1 a total of two sequence variants were found amongst Parramatta River amphipods and three sequence variants among Hawkesbury River animals, with no common variants across the two river systems. To establish whether genetic differences were associated with organismal responses to toxicant exposure, two life-history trait variables (female head length as an estimator of amphipod size and female fecundity) were analyzed. Life-history trait analyses showed that females from the Hawkesbury River were significantly larger and more fecund. These data have critical implications for toxicity tests, the use of laboratory cultures for testing purposes, and environmental contamination in Sydney Harbor

  7. Genetic and life-history trait variation of the amphipod Melita plumulosa from polluted and unpolluted waterways in eastern Australia

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Pann Pann [Evolution and Ecology Research Centre, School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney 2052 (Australia); Hyne, Ross V. [Ecotoxicology and Environmental Contaminants Section, NSW Department of Environment and Climate Change, PO Box 29, Lidcombe, NSW 1825 (Australia); Mann, Reinier M. [Centre for Ecotoxicology, Department of Environmental Sciences, University of Technology-Sydney, C/-PO Box 29, Lidcombe, NSW 1825 (Australia); Ballard, J. William O. [Evolution and Ecology Research Centre, School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney 2052 (Australia)], E-mail: w.ballard@unsw.edu.au

    2008-09-15

    To monitor genetic diversity and environmental contamination in eastern Australia, toxicity studies have employed the sensitive benthic amphipod Melita plumulosa. The goal of this study was to examine the genetic and life-history variability of natural populations of M. plumulosa from the Parramatta (polluted) and Hawkesbury (unpolluted) Rivers. The underlying genetics of the populations in these distinct waterways was examined at one mitochondrial (cytochrome c oxidase subunit I (COI)) and one nuclear (ribosomal internal transcribed spacer region 1 (ITS1)) locus. Seven unique haplotypes for COI were found amongst animals from the Parramatta River, while animals from the Hawkesbury River showed a complete absence of genetic variation at this locus. At ITS1 a total of two sequence variants were found amongst Parramatta River amphipods and three sequence variants among Hawkesbury River animals, with no common variants across the two river systems. To establish whether genetic differences were associated with organismal responses to toxicant exposure, two life-history trait variables (female head length as an estimator of amphipod size and female fecundity) were analyzed. Life-history trait analyses showed that females from the Hawkesbury River were significantly larger and more fecund. These data have critical implications for toxicity tests, the use of laboratory cultures for testing purposes, and environmental contamination in Sydney Harbor.

  8. Examining the effects of hurricanes Matthew and Irma on water quality in the intracoastal waterway, St. Augustine, FL.

    Science.gov (United States)

    Ward, N. D.; Osborne, T.; Dye, T.; Julian, P.

    2017-12-01

    The last several years have been marked by a high incidence of Atlantic tropical cyclones making landfall as powerful hurricanes or tropical storms. For example, in 2016 Hurricane Matthew devastated parts of the Caribbean and the southeastern United States. In 2017, this region was further battered by hurricanes Irma and Maria. Here, we present water quality data collected in the intracoastal waterway near the Whitney Lab for Marine Bioscience during hurricanes Matthew and Irma, a region that experienced flooding during both storms. YSI Exo 2 sondes were deployed to measure pH, salinity, temperature, dissolved O2, fluorescent dissolved organic matter (fDOM), turbidity, and Chlorophyll-a (Chl-a) on a 15 minute interval. The Hurricane Matthew sonde deployment failed as soon as the storm hit, but revealed an interesting phenomenon leading up to the storm that was also observed during Irma. Salinity in the intracoastal waterway (off the Whitney Lab dock) typically varies from purely marine to 15-20 psu throughout the tidal cycle. However, several days before both storms approached the Florida coast (i.e. when they were near the Caribbean), the salinity signal became purely marine, overriding any tidal signal. Anecdotally, storm drains were already filled up to street level prior to the storm hitting, poising the region for immense flooding and storm surge. The opposite effect was observed after Irma moved past FL. Water became much fresher than normal for several days and it took almost a week to return to "normal" salinity tidal cycles. As both storms hit, turbidity increased by an order of magnitude for a several hour period. fDOM and O2 behaved similar to salinity during and after Irma, showing a mostly marine signal (e.g. higher O2, lower fDOM) in the lead up, and brief switch to more freshwater influence the week after the storm. Chl-a peaked several days after the storm, presumably due to mobilization of nutrient rich flood and waste waters and subsequent algae

  9. Adaptation and penetration of resin-based root canal sealers in root canals irradiated with high-intensity lasers.

    Science.gov (United States)

    Moura-Netto, Cacio; Mello-Moura, Anna Carolina Volpi; Palo, Renato Miotto; Prokopowitsch, Igor; Pameijer, Cornelis H; Marques, Marcia Martins

    2015-03-01

    This research analyzed the quality of resin-based sealer adaptation after intracanal laser irradiation. Extracted teeth (n = 168) were root canal treated and divided into four groups, according to dentin surface treatment: no laser; Nd:YAG laser (1.5 W, 100 mJ, 15 Hz); diode laser (2.5 W in CW), and Er:YAG laser (1 W, 100 mJ, 10 Hz). The teeth were divided into four subgroups according to the sealer used: AH Plus, EndoREZ, Epiphany, and EpiphanySE. For testing the sealing after root canal obturation, the penetration of silver nitrate solution was measured, whereas to evaluate the adaptation and penetration of the sealer into the dentin, environmental scanning electron microscopy (ESEM) was used. The ESEM images were analyzed using a four-grade criteria score by three evaluators. The inter-examiner agreement was confirmed by Kappa test and the scores statistically compared by the Kruskal-Wallis' test (p laser irradiation. Nd:YAG and diode laser decreased the tracer penetration for AH Plus, whereas EndoREZ and EpiphanySE performances were affected by Nd:YAG irradiation (p laser irradiation can be used as an adjunct in endodontic treatment; however, the use of hydrophilic resin sealers should be avoided when root canals were irradiated with Nd:YAG laser.

  10. Measurement and visualization of file-to-wall contact during ultrasonically activated irrigation in simulated canals.

    Science.gov (United States)

    Boutsioukis, C; Verhaagen, B; Walmsley, A D; Versluis, M; van der Sluis, L W M

    2013-11-01

    (i) To quantify in a simulated root canal model the file-to-wall contact during ultrasonic activation of an irrigant and to evaluate the effect of root canal size, file insertion depth, ultrasonic power, root canal level and previous training, (ii) To investigate the effect of file-to-wall contact on file oscillation. File-to-wall contact was measured during ultrasonic activation of the irrigant performed by 15 trained and 15 untrained participants in two metal root canal models. Results were analyzed by two 5-way mixed-design anovas. The level of significance was set at P root canal (P root canal (P irrigant activation. Therefore, the term 'Passive Ultrasonic Irrigation' should be amended to 'Ultrasonically Activated Irrigation'. © 2013 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  11. Micro-CT evaluation of root and canal morphology of mandibular first premolars with radicular grooves

    Energy Technology Data Exchange (ETDEWEB)

    Boschetti, Emanuele; Mazzi-Chaves, Jardel Francisco; Versiani, Marco Aurélio; Pécora, Jesus Djalma; Saquy, Paulo Cesar; Sousa Neto, Manoel Damião de, E-mail: sousanet@forp.usp.br [Universidade de São Paulo (USP), Ribeirao Preto, SP (Brazil). Departamento de Odontologia Restauradora; Silva-Sousa, Yara Terezinha Correa; Leoni, Graziela Bianchi [Universidade de Ribeirão Preto (UNAERP), Ribeirão Preto, SP (Brazil). Departmento de Endodontia

    2017-09-15

    The aim of this study was to evaluate morphological features of 70 single-rooted mandibular first premolars with radicular grooves (RG) using micro-CT technology. Teeth were scanned and evaluated regarding the morphology of the roots and root canals as well as length, depth and percentage frequency location of the RG. Volume, surface area and Structure Model Index (SMI) of the canals were measured for the full root length. Two-dimensional parameters and frequency of canal orifices were evaluated at 1, 2, and 3 mm levels from the apical foramen. The number of accessory canals, the dentin thickness, and cross-sectional appearance of the canal at different root levels were also recorded. Expression of deep grooves was observed in 21.42% of the sample. Mean lengths of root and RG were 13.43 mm and 8.5 mm, respectively, while depth of the RG ranged from 0.75 to 1.13 mm. Mean canal volume, surface area and SMI were 10.78 mm{sup 3}, 58.51 mm{sup 2}, and 2.84, respectively. Apical delta was present in 4.35% of the sample and accessory canals were observed mostly at the middle and apical thirds. Two-dimensional parameters indicated an oval-shaped cross-sectional appearance of the root canal with a high percentage frequency of canal divisions (87.15%). Canal configuration type V (58.57%) was the most prevalent. C-shaped configuration was observed in 13 premolars (18.57%), whereas dentin thickness ranged from 1.0 to 1.31 mm. Radicular grooves in mandibular first premolars was associated with the occurrence of several anatomical complexities, including C-shaped canals and divisions of the main root canal. (author)

  12. Micro-CT evaluation of root and canal morphology of mandibular first premolars with radicular grooves

    International Nuclear Information System (INIS)

    Boschetti, Emanuele; Mazzi-Chaves, Jardel Francisco; Versiani, Marco Aurélio; Pécora, Jesus Djalma; Saquy, Paulo Cesar; Sousa Neto, Manoel Damião de; Silva-Sousa, Yara Terezinha Correa; Leoni, Graziela Bianchi

    2017-01-01

    The aim of this study was to evaluate morphological features of 70 single-rooted mandibular first premolars with radicular grooves (RG) using micro-CT technology. Teeth were scanned and evaluated regarding the morphology of the roots and root canals as well as length, depth and percentage frequency location of the RG. Volume, surface area and Structure Model Index (SMI) of the canals were measured for the full root length. Two-dimensional parameters and frequency of canal orifices were evaluated at 1, 2, and 3 mm levels from the apical foramen. The number of accessory canals, the dentin thickness, and cross-sectional appearance of the canal at different root levels were also recorded. Expression of deep grooves was observed in 21.42% of the sample. Mean lengths of root and RG were 13.43 mm and 8.5 mm, respectively, while depth of the RG ranged from 0.75 to 1.13 mm. Mean canal volume, surface area and SMI were 10.78 mm 3 , 58.51 mm 2 , and 2.84, respectively. Apical delta was present in 4.35% of the sample and accessory canals were observed mostly at the middle and apical thirds. Two-dimensional parameters indicated an oval-shaped cross-sectional appearance of the root canal with a high percentage frequency of canal divisions (87.15%). Canal configuration type V (58.57%) was the most prevalent. C-shaped configuration was observed in 13 premolars (18.57%), whereas dentin thickness ranged from 1.0 to 1.31 mm. Radicular grooves in mandibular first premolars was associated with the occurrence of several anatomical complexities, including C-shaped canals and divisions of the main root canal. (author)

  13. Toxicity of harbour canal sediments before dredging and after off shore disposal

    NARCIS (Netherlands)

    Van den Hurk, P.; Eertman, R.H.M.; Stronkhorst, J.

    1997-01-01

    Dredge material from an entrance waterway to the port of Rotterdam and sediments from the North Sea off-shore disposal site were tested for toxicity using three different sediment bioassays, The goals of the study were to evaluate if bioassays generate useful additional information to chemical based

  14. Canal transportation and centering ability of protaper and self-adjusting file system in long oval canals: An ex-vivo cone-beam computed tomography analysis.

    Science.gov (United States)

    Shah, Dipali Yogesh; Wadekar, Swati Ishwara; Dadpe, Ashwini Manish; Jadhav, Ganesh Ranganath; Choudhary, Lalit Jayant; Kalra, Dheeraj Deepak

    2017-01-01

    The purpose of this study was to compare and evaluate the shaping ability of ProTaper (PT) and Self-Adjusting File (SAF) system using cone-beam computed tomography (CBCT) to assess their performance in oval-shaped root canals. Sixty-two mandibular premolars with single oval canals were divided into two experimental groups ( n = 31) according to the systems used: Group I - PT and Group II - SAF. Canals were evaluated before and after instrumentation using CBCT to assess centering ratio and canal transportation at three levels. Data were statistically analyzed using one-way analysis of variance, post hoc Tukey's test, and t -test. The SAF showed better centering ability and lesser canal transportation than the PT only in the buccolingual plane at 6 and 9 mm levels. The shaping ability of the PT was best in the apical third in both the planes. The SAF had statistically significant better centering and lesser canal transportation in the buccolingual as compared to the mesiodistal plane at the middle and coronal levels. The SAF produced significantly less transportation and remained centered than the PT at the middle and coronal levels in the buccolingual plane of oval canals. In the mesiodistal plane, the performance of both the systems was parallel.

  15. 75 FR 5769 - Inland Waterways Users Board; Request for Nominations

    Science.gov (United States)

    2010-02-04

    ... ``various'' regions. For the purpose of selecting Board members, the waterways subjected to fuel taxes and... Products; (2) Coal and Coke; (3) Petroleum, Crude and Products; (4) Minerals, Ores, and Primary Metals and...

  16. Radiographic evaluation of the course and visibility of the mandibular canal

    International Nuclear Information System (INIS)

    Jung, Yun Hoa; Cho, Bong Hae

    2014-01-01

    This study was performed to investigate the course of the mandibular canal on panoramic radiography and the visibility of this canal on both panoramic radiography and cone-beam computed tomography (CBCT). The study consisted of panoramic radiographs and CBCT images from 262 patients. The course of the mandibular canal, as seen in panoramic radiographs, was classified into four types: linear, elliptical, spoon-shaped, and turning curves. The visibility of this canal from the first to the third molar region was evaluated by visually determining whether the mandibular canal was clearly visible, probably visible, or invisible. The visibility of the canal on panoramic radiographs was compared with that on CBCT images. Elliptical curves were most frequently observed along the course of the mandibular canal. The percentage of clearly visible mandibular canals was the highest among the spoon-shaped curves and the lowest among the linear curves. On panoramic radiographs, invisible mandibular canals were found in 22.7% of the examined sites in the first molar region, 11.8% in the second molar region, and 1.3% in the third molar region. On CBCT cross-sectional images, the mandibular canal was invisible in 8.2% of the examined sites in the first molar region, 5.7% in the second molar region, and 0.2% in the third molar region. The visibility of this canal was lower in the first molar region than in the third molar region. The mandibular canal presented better visibility on CBCT images than on panoramic radiographs.

  17. Carcinoma of the external auditory canal and middle ear

    International Nuclear Information System (INIS)

    Pfreundner, Leo; Schwager, Konrad; Willner, Jochen; Baier, Kurt; Bratengeier, Klaus; Brunner, Franz Xaver; Flentje, Michael

    1999-01-01

    Purpose: To evaluate therapeutic modalities used at our institutions regarding local control, disease-free survival and actuarial survival in carcinoma of the external auditory canal and middle ear, in an attempt to provide guidelines for therapy. Methods and Materials: A series of 27 patients with carcinoma of the external auditory canal and middle ear treated between 1978 and 1997 in our institutions were analyzed with particular reference to tumor size and its relation to surrounding tissues, patterns of neck node involvement, surgical procedures, and radiation techniques employed. Clinical endpoints were freedom from local failure, overall survival, and disease-free survival. The median follow-up was 2.7 years (range 0.1-17.9 years). Results: Treatment by surgery and radiotherapy resulted in an overall 5-year survival rate of 61%. According to the Pittsburgh classification, the actuarial 5-year survival rate for early disease (T1 and T2 tumors) was 86%, for T3 tumors 50%, and T4 stages 41%. Patients with tumors limited to the external auditory canal had a 5-year survival rate of 100%, patients with tumor invasion of the temporal bone 63%, and patients with tumor infiltration beyond the temporal bone 38%. The rate of freedom from local recurrence was 50% at 5 years. Unresectability by dural and cerebral infiltration, and treatment factors such as complete resection or resection with tumor beyond surgical margins are of prognostic relevance. All patients with dural invasion died within 2.2 years. The actuarial 5-year survival rate of patients with complete tumor resection was 100%, but 66% in patients with tumor beyond surgical margins. 192 Iridium high-dose-rate (HDR) afterloading brachytherapy based on three-dimensional computed tomography (3D CT)-treatment planning was an effective tool in management of local recurrences following surgery and a full course of external beam radiotherapy. Conclusion: Surgical resection followed by radiotherapy adapted to stage

  18. Conflict analysis and management alternative for the Manayunk Canal

    International Nuclear Information System (INIS)

    Chadderton, R.A.

    1989-01-01

    The solution of a water resource allocation problem by an alternative social arrangement is presented. Classical Austrian economic theory and the new resources economics provide both theoretical and practical evidence to support the development of well-defined, private property rights to the water resource in question. A conflict analysis demonstrates that management of the Manayunk Canal by a firm would reconcile existing confrontations through compromise use of the water resource. Benefit and cost calculations show that a compromise among industrial and recreational interests, currently competing in the political arena, would increase social benefits

  19. Effects of irrigation solutions and Calcium hydroxide dressing on root canal treatments of periapical lesions

    Directory of Open Access Journals (Sweden)

    Vita Nirmala

    2006-03-01

    Full Text Available The preparation of root canal in endodontic treatment plays an important role in treating non vital teeth with periapical lesion. Some factors influence the success of root canal treatment in short and long terms are the irrigation of root canal using antiseptic solution and the use of root canal medicament. The aim of this literature study is to determined the effect of irrigation solution and Calcium hydroxide dressing in root canal treatment of periapical lesions. The use of root canal medicament during the endodontic treatment could sterilized and decreased the number of pathogenic microorganism of root canal. An effective root canal irrigation solution must be able to dissolve organic and anorganic debris, lubricate endodontic instruments, disinfect microorganisms, non toxic and economical. The best irrigation solution has maximum antimicrobial effect with minimum toxicity. Division of calcium hydroxide into Calcium and hydroxyl ions is responsible for alkalinization of cavity, subsequently it makes the condition of cavity to be inappropriate for bacterial endotoxin in vitro as well as in vivo, and considered as the only clinically effective medicament in inactivating bacterial endotoxin. Calcium hydroxide is the only medication which has the ability to clinically inactive bacterial endotoxin in vitro in vivo and accepted as the best of root canal medication.

  20. Nutrient Canals of the Alveolar Process as an Anatomical Feature for Age and Gender Determination

    Directory of Open Access Journals (Sweden)

    Prashant Gupta

    2017-01-01

    Full Text Available Introduction: Nutrient canals are anatomic structures of the alveolar bone through which neurovascular elements transit to supply teeth and supporting structures. Dental identification using nutrient canal of the mandibular alveolar process as the most compelling anatomic feature for antemortem–postmortem radiographic comparison can be potentially used in forensic identification. Aim: The aim of the present study was to investigate the correlation between the appearance of nutrient canals as a potential clue to age and gender determination. Materials and Methods: One hundred and twenty patients, 60 males and 60 females, were selected in the 11–60-year age group. Systemic disease, especially hypertension, was ruled out in the patients. Periapical radiographs were taken from mandibular anterior cuspid central incisor region because nutrient canals are commonly observed in this area. Data obtained was analyzed by SPSS software and various statistical analysis were carried out. Results: Study revealed nutrient canals to be commonly seen in females compared to males. Males had maximum canals in the age group of 21–30-year whereas females in the age group of 31–40 years had the maximum canals. Conclusion: Significant correlation was seen between the gender and nutrient canals whereas no significant correlation existed between the age and presence of nutrient canals.

  1. [Benign paroxysmal positional vertigo of the anterior semicircular canal: clinical aspects and treatment].

    Science.gov (United States)

    Lorin, P

    2005-01-01

    To describe the videonystagmographic characteristics and the treatment of the patients reached with a canalolithiasis or a cupulolithiasis of the anterior semicircular canal. Retrospective study concerning patients treated for a Benign Paroxysmal Positional Vertigo (BPPV) of the anterior semicircular canal. Each patient after analysis under videonystagmoscopy (VNS) and under videonystagmography (VNG) was treated by maneuvers. On 462 observations of typical BPPV 6 cases of VPPB of the anterior semicircular canal were treated concerning 5 patients (1.3%). The BPPV of the anterior semicircular canal are rare. We modified our method of diagnosis, and our therapeutic techniques could be validated with the help of the two-dimensional videonystagmography.

  2. 77 FR 47826 - Inland Waterways Users Board; Request for Nominations

    Science.gov (United States)

    2012-08-10

    ... the Board, the waterways subjected to fuel taxes and described in Public Law 95-502, as amended, have... United States. These categories are (1) Farm and Food Products; (2) Coal and Coke; (3) Petroleum, Crude...

  3. Endodontic treatment of a mandibular first molar with three mesial canals and broken instrument removal.

    Science.gov (United States)

    Faramarzi, Farhad; Fakhri, Hamidreza; Fakri, Hamidreza; Javaheri, Homan H

    2010-04-01

    To succeed in any dental procedure, the clinician's awareness of the patient's dental anatomy and its variations is crucial. In endodontic therapy, obtaining full information about the root canals' variations can affect the outcome substantially. This case report presents the endodontic treatment of a mandibular first molar exhibiting three mesial root canals with 4 mm of a separated K-file in the coronal third of the mesiolingual canal on an 18-year-old female patient. This case demonstrates the importance of locating additional canals in any roots undergoing endodontic treatment and how the clinician's awareness of aberrant internal anatomy may change the treatment results.

  4. Tumors of the spinal cord and canal

    International Nuclear Information System (INIS)

    Karlsson, U.L.; Brady, L.W.

    1987-01-01

    Most spine (primary and secondary) neoplasms should receive curative or palliative radiation therapy. Data from the literature support its use as a beneficial treatment modality. Meningiomas and neurofibromas should be resected and irradiated postoperatively if removed subtotally or if the histopathology is malignant. The prognosis for patients with these tumors is generally good. Intramedullary tumors should be biopsied and irradiated when neoplastic histology has been established. The prognosis for these patients is unsatisfactory for high-grade astrocytomas but is more reasonable for ependymomas and vascular malformations. A favorable exception may be the myxopapillary ependymoma in the lumbosacral region. It should be maximally resected with sparing of cauda equina function but then irradiated postoperatively. The primary intent should be to eradicate the tumor. Radiation therapy is the main treatment modality, with steroid medication, in cases of cord compression

  5. The KRA Canal and Thai Security

    Science.gov (United States)

    2002-06-01

    created pockets of minorities; many carry diseases such as elephantiasis and malaria. For example, Ranong Province is presently facing the recurrence...of elephantiasis . This disease, which had long disappeared from Thailand, is now spreading rapidly.42 Furthermore, some of the illegal workers are

  6. Heavy metal contents and other physical quality indices of sewerage, canal and drinking water

    International Nuclear Information System (INIS)

    Mahmood, S.; Sattar, A.; Ihsanullash; Atta, S.; Arif, S. University of Engineering and Technology, Peshawar

    2001-01-01

    Analysis of Cd, Pb and Cu in canal, sewerage and drinking water by potentiometric stripping analysis (PSA) is described. Other quality indices of water such as temperature, pH, EC and total solid were also determined. The levels of heavy metal contents of sewerage, canal and drinking water revealed marked differences and wide coefficient of variability (CV). Generally Cd and Pb contents were higher in sewerage than canal and drinking water. However, Cu content of drinking waters was higher than other water tested. The total solids were found to be generally higher in sewerage and canal water than drinking water tested. The total solids were found to be generally higher in sewerage and canal water than drinking water The variations in temperature, pH and EC were marginal to marked depending upon the source and the location. (author)

  7. Charlemagne's summit canal: an early medieval hydro-engineering project for passing the Central European Watershed.

    Science.gov (United States)

    Zielhofer, Christoph; Leitholdt, Eva; Werther, Lukas; Stele, Andreas; Bussmann, Jens; Linzen, Sven; Schneider, Michael; Meyer, Cornelius; Berg-Hobohm, Stefanie; Ettel, Peter

    2014-01-01

    The Central European Watershed divides the Rhine-Main catchment and the Danube catchment. In the Early Medieval period, when ships were important means of transportation, Charlemagne decided to link both catchments by the construction of a canal connecting the Schwabian Rezat and the Altmühl rivers. The artificial waterway would provide a continuous inland navigation route from the North Sea to the Black Sea. The shortcut is known as Fossa Carolina and represents one of the most important Early Medieval engineering achievements in Europe. Despite the important geostrategic relevance of the construction it is not clarified whether the canal was actually used as a navigation waterway. We present new geophysical data and in situ findings from the trench fills that prove for the first time a total length of the constructed Carolingian canal of at least 2300 metres. We have evidence for a conceptual width of the artificial water course between 5 and 6 metres and a water depth of at least 60 to 80 cm. This allows a crossing way passage of Carolingian cargo scows with a payload of several tons. There is strong evidence for clayey to silty layers in the trench fills which reveal suspension load limited stillwater deposition and, therefore, the evidence of former Carolingian and post-Carolingian ponds. These findings are strongly supported by numerous sapropel layers within the trench fills. Our results presented in this study indicate an extraordinarily advanced construction level of the known course of the canal. Here, the excavated levels of Carolingian trench bottoms were generally sufficient for the efficient construction of stepped ponds and prove a final concept for a summit canal. We have evidence for the artificial Carolingian dislocation of the watershed and assume a sophisticated Early Medieval hydrological engineering concept for supplying the summit of the canal with adequate water.

  8. LNG as a marine and inland waterway fuel. Contribution of AFG (French gas association) to the national policy framework for the deployment of alternative fuel infrastructures (AFNPF)

    International Nuclear Information System (INIS)

    2016-06-01

    Here in the early 21. Century, the environmental footprint of marine and inland waterway transport is a major concern on a global scale. Under the authority of the International Maritime Organisation (IMO), regulations on atmospheric emissions are becoming increasingly tighter. The European Union (EU) is deeply committed to this endeavour and in particular has adopted Directive 2014/94/EU which aims to facilitate the deployment of an alternative fuels infrastructure. The Directive calls upon Member States to develop by 18 November 2016, national policy frameworks for the deployment of alternative fuel infrastructures (AFNPF) that must designate an appropriate number of LNG refuelling points in maritime and inland ports for maritime and inland waterway transport purposes. In light of this, the French Gas Association (AFG), in cooperation with all affected stakeholders and interested parties, has discussed the role of LNG as a marine and inland waterway fuel in the energy transition toward green growth, in order to contribute to the development of France's 'national policy framework' (AFNPF) under the Directive mentioned above. To assess the prospects of the LNG bunkering market in France, as well as the implementation of the corresponding infrastructures, the AFG adopted a scenario-based approach from the user's perspective. Considering that we are in an early stage, the study focuses on the types of ships that are most likely to use LNG, and it examines their traffic in France's major metropolitan ports, along with forecasted activity based on the strategic plans for those ports. Two scenarios - one being rather conservative (baseline) and the other being more optimistic - were examined over three timelines: 2020, 2025 and 2030. The scenarios lead to a gradual implementation of LNG fuel in French ports, on the three coastlines and along the five inland waterway corridors. They show LNG fuel needs in all the ports of the central TEN

  9. Comparative study of 6 rotary nickel-titanium systems and hand instrumentation for root canal preparation in severely curved root canals of extracted teeth.

    Science.gov (United States)

    Celik, Davut; Taşdemir, Tamer; Er, Kürşat

    2013-02-01

    Some improvements have been developed with new generations of nickel-titanium (NiTi) rotary instruments that led to their successful and extensive application in clinical practice. The purpose of this in vitro study was to compare the root canal preparations performed by using GT Series X and Twisted File systems produced by innovative manufacturing process with Revo-S, RaCe, Mtwo, and ProTaper Universal systems manufactured directly from conventional nitinol and with stainless steel K-Flexofile instruments. The mesiobuccal root canals of 140 maxillary first permanent molars that had between 30°-40° curvature angle and 4- to 9-mm curvature radius of the root canal were used. After root canal preparations made by using GT Series X, Twisted File, Revo-S, RaCe, Mtwo, and ProTaper Universal NiTi rotary systems and stainless steel K-Flexofile instruments, transportation occurred in the root canal, and alteration of working length (WL) was assessed by using a modified double-digital radiographic technique. The data were compared by the post hoc Tukey honestly significant difference test. NiTi rotary systems caused less canal transportation and alteration of WL than K-Flexofile instruments (P .05) except 2.5 mm from the WL. At this level ProTaper Universal system caused significant canal transportation (P ProTaper Universal rotary systems manufactured by traditional methods. Copyright © 2013 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  10. Utricular paresis and semicircular canal hyperactivity: a distinct otolith syndrome.

    Science.gov (United States)

    Angeli, Simon I; Snapp, Hillary; Velandia, Sandra; Morgenstein, Kari

    2015-04-01

    Although combined utricular and canal paresis has been described previously, this is the first report of canal hyperactivity associated with utricular hypofunction. Unsteadiness and swaying were the most common symptoms, and patients with shorter duration of symptoms also had positional vertigo. We propose that this syndrome is a variant of utricular dysfunction and should be considered in the differential diagnosis of peripheral vestibular disorders. To describe a syndrome of instability associated with utricular dysfunction and hyperactive caloric responses. The study comprised 11 consecutive patients exhibiting abnormalities of the eccentric subjective visual vertical test (e-SVV) and high responses during the caloric test of the videonystagmography (VNG). We carried out a review of symptoms, physical examination, and vestibular tests. There was no gender predilection or obvious etiology. The patients' main complaint included instability with linear symptoms (i.e., tilting, rocking, and swaying), with positional vertigo as a secondary symptom. Oculomotor testing, visual fixation index, and brain MRI were normal, excluding a central nervous system disorder. VNG was essentially normal except for hyperactive responses during the caloric testing in all patients. Abnormal e-SVV was found in 10 patients unilaterally and bilaterally in 1 patient. Abnormal oVEMP was found in seven of seven patients, further supporting a utricular site of lesion.

  11. Overt and occult vidian canal involvement in juvenile angiofibroma and its possible impact on recurrence.

    Science.gov (United States)

    Thakar, Alok; Hota, Ashutosh; Bhalla, Ashu Seth; Gupta, Siddharth Datta; Sarkar, Chitra; Kumar, Rakesh

    2016-04-01

    Postexcision residual disease in the vidian canal is speculated to contribute to recurrence in juvenile angiofibroma. We composed a prospective cohort of 16 consecutive patients with juvenile angiofibroma (stages IIA-IIIB). The presurgical vidian canal assessment was done by contrast-enhanced CT (1.2 mm collimation). At surgery after complete tumor excision, the vidian canal tissue was sampled for histology. Postexcision drilling of the vidian canal was done in 8 of 15 patients to remove microscopic residual disease, with a 24 to 48 month follow-up period. Presurgical radiology indicated ipsilateral vidian canal enlargement (≥3 mm)/destruction in 13 of 16 patients. Radiologically occult involvement was documented only by histology in another 1 of 16 patients. Postexcision sampling of the vidian canal noted microscopic residual tumor in 3 of 15 patients. No recurrences were noted in 8 cases (0 of 8) with postexcision drilling of the vidian canal and 2 recurrences in 7 cases (2 of 7) with no drilling (p = .20). Vidian canal involvement in juvenile angiofibroma is almost universal (14 of 16) and may be occult to CT evaluation. The site may harbor microscopic residual tumor after seemingly complete excision. Surgical attention toward it may reduce recurrences. © 2015 Wiley Periodicals, Inc. Head Neck 38: E421-425, 2016. © 2015 Wiley Periodicals, Inc.

  12. CANAL code

    International Nuclear Information System (INIS)

    Gara, P.; Martin, E.

    1983-01-01

    The CANAL code presented here optimizes a realistic iron free extraction channel which has to provide a given transversal magnetic field law in the median plane: the current bars may be curved, have finite lengths and cooling ducts and move in a restricted transversal area; terminal connectors may be added, images of the bars in pole pieces may be included. A special option optimizes a real set of circular coils [fr

  13. Understanding the economic, environmental and energy consequences of the Panama Canal expansion on Midwest grain and agricultural exports.

    Science.gov (United States)

    2011-05-01

    The Panama Canal Authority (ACP) is currently building a third lock scheduled to open in 2014, significantly changing the capacity of the : canal for inter-ocean movements. Midwest specialty grain and agricultural product exporters will be directly a...

  14. 77 FR 69562 - Drawbridge Operation Regulation; Thea Foss Waterway Previously Known as City Waterway, Tacoma, WA

    Science.gov (United States)

    2012-11-20

    ... shape in the ``Actions'' column. If you submit your comments by mail or hand delivery, submit them in an... unique features of the Murray Morgan Bridge is its height above the waterway providing 60 feet of... bridge openings are for locally moored and operated recreational sailboats with mast heights over 60 feet...

  15. Current diagnosis of tumors developed in the internal auditory canal and cerebellopontine angle

    International Nuclear Information System (INIS)

    Vignaud, J.; Doyon, D.

    1988-01-01

    The introduction of CT scan and, more recently, magnetic resonance imaging, has radically changed the diagnostic approach to tumors developed in the internal auditory canal and cerebellopontine angle. CT scan with intravenous injection visualizes tumors lying in the cerebellopontine angle. Magnetic resonance imaging, especially using gadolinium, is a very accurate means for diagnosing tumors of both the auditory canal and cerebellopontine angle [fr

  16. The impact of the New Panama Canal Locks on Texas ports and the Texas economy.

    Science.gov (United States)

    2017-10-01

    This report examines the first year transits through the new Panama Canal locks and its impact on Texas deep water ports. It finds that the canal is operating efficiently and can accommodate 14,000 TEU containerships and bulk vessels up to 125,000 to...

  17. Endodontic Management of a Maxillary Lateral Incisor with 4 Root Canals and a Dens Invaginatus Tract.

    Science.gov (United States)

    Nosrat, Ali; Schneider, S Craig

    2015-07-01

    Dens invaginatus (DI) is associated with complex internal anatomy. This article represents a maxillary lateral incisor with 5 root canals including DI. The treatment was planned and performed using cone-beam computed tomographic (CBCT) imaging. After clinical and radiographic evaluations, tooth #7 was diagnosed with DI and pulp necrosis with symptomatic apical periodontitis. Periapical radiographs of the tooth showed 2 roots and complex internal anatomy. CBCT evaluation revealed tooth #7 had 5 separate canals (4 root canals and 1 DI canal extending through the root to the periodontal ligament), communication between DI and the root canal system, and severe and multiple curvatures of the palatal canals. Root canal treatment was completed in 2 visits. Modified access openings were required to safely treat the dilacerated palatal canals. At the 6-month re-evaluation, the patient reported he had remained asymptomatic and his tooth had remained functional since the treatment was completed. Clinical examination showed tooth #7 had no sensitivity to percussion or palpation, probe depths within normal limits (≤3 mm), and no mobility. Radiographic assessment of the tooth showed significant osseous healing of the preoperative lesion. Three-dimensional imaging is a valuable tool for endodontic management of teeth with complex internal anatomy. Three-dimensional imaging is recommended for evaluating and treatment planning cases with DI. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  18. Root and Canal Morphology of Mandibular Third Molars in an Iranian Population

    Directory of Open Access Journals (Sweden)

    Maryam Kuzekanani

    2012-06-01

    Full Text Available Background and aims. A through knowledge of the root canal morphology is required for successful endodontic therapy. The aim of this study was to investigate the root and canal morphology of mandibular third molars in Kerman, a province in southeast of Iran. Materials and methods. One-hundred-fifty extracted mandibular third molars were collected randomly from different dental clinics in Kerman. The root canal anatomy and morphology of each tooth was carefully studied using a clearing technique. Root number and morphology, number of canals per root, root canal configuration according to Vertucci classification, and incidence of dilacerated roots and C-shaped canals in mandibular third molars were evaluated under stereomicroscope with ×2 to ×3 magnifications. Results. From the total of 150 mandibular third molars studied, 21% had one root. The majority of teeth (73% had two roots. 5.5% of the teeth had three roots. The incidence of C-shaped canal was 3.5% in this study and 8% of the teeth had at least one dilacerated root. Conclusion. Although root canal anatomy and morphology of mandibular third molars is very variable having two roots seems to be the normal anatomy for these teeth.

  19. Interaction of Aquifer and River-Canal Network near Well Field.

    Science.gov (United States)

    Ghosh, Narayan C; Mishra, Govinda C; Sandhu, Cornelius S S; Grischek, Thomas; Singh, Vikrant V

    2015-01-01

    The article presents semi-analytical mathematical models to asses (1) enhancements of seepage from a canal and (2) induced flow from a partially penetrating river in an unconfined aquifer consequent to groundwater withdrawal in a well field in the vicinity of the river and canal. The nonlinear exponential relation between seepage from a canal reach and hydraulic head in the aquifer beneath the canal reach is used for quantifying seepage from the canal reach. Hantush's (1967) basic solution for water table rise due to recharge from a rectangular spreading basin in absence of pumping well is used for generating unit pulse response function coefficients for water table rise in the aquifer. Duhamel's convolution theory and method of superposition are applied to obtain water table position due to pumping and recharge from different canal reaches. Hunt's (1999) basic solution for river depletion due to constant pumping from a well in the vicinity of a partially penetrating river is used to generate unit pulse response function coefficients. Applying convolution technique and superposition, treating the recharge from canal reaches as recharge through conceptual injection wells, river depletion consequent to variable pumping and recharge is quantified. The integrated model is applied to a case study in Haridwar (India). The well field consists of 22 pumping wells located in the vicinity of a perennial river and a canal network. The river bank filtrate portion consequent to pumping is quantified. © 2014, National GroundWater Association.

  20. Building and Testing a Statistical Shape Model of the Human Ear Canal

    DEFF Research Database (Denmark)

    Paulsen, Rasmus Reinhold; Larsen, Rasmus; Laugesen, Søren

    2002-01-01

    Today the design of custom in-the-ear hearing aids is based on personal experience and skills and not on a systematic description of the variation of the shape of the ear canal. In this paper it is described how a dense surface point distribution model of the human ear canal is built based on a t...

  1. Comparison of root canal lathing measurement by conventional and digital radiology

    International Nuclear Information System (INIS)

    Mitrova, N.; Slavik, J.; Cecetkova, A.; Jenca, A.; Hanusinova, V.; Ondrasovicova, J.

    2006-01-01

    A correct working length is a critical factor within the endodontic treatment. The length of the root canal can be measured by different methods. The aim of this study was to compare methods used for measuring the length of root canals using conventional and digital radiology. The measurement was provided in both - in vitro and in vivo conditions. (authors)

  2. Simulation of hypothetical Asian carp egg and larvae development and transport in the Lockport, Brandon Road, Dresden Island, and Marseilles Pools of the Illinois Waterway by use of the Fluvial Egg Drift Simulator (FluEgg) model

    Science.gov (United States)

    Murphy, Elizabeth A.; Garcia, Tatiana; Jackson, P. Ryan; Duncker, James J.

    2016-04-05

    As part of the Great Lakes and Mississippi River Interbasin Study, the U.S. Army Corps of Engineers (USACE) is conducting an assessment of the vulnerability of the Chicago Area Waterway System and Des Plaines River to Asian carp (specifically, Hypophthalmichthys nobilis (bighead carp) and Hypophthalmichthys molitrix (silver carp)) spawning and recruitment. As part of this assessment, the USACE requested the help of the U.S. Geological Survey in predicting the fate and transport of Asian carp eggs hypothetically spawned at the electric dispersal barrier on the Chicago Sanitary and Ship Canal and downstream of the Brandon Road Lock and Dam on the Des Plaines River under dry weather flow and high water temperature conditions. The Fluvial Egg Drift Simulator (FluEgg) model predicted that approximately 80 percent of silver carp eggs spawned near the electric dispersal barrier would hatch within the Lockport and Brandon Road pools (as close as 3.6 miles downstream of the barrier) and approximately 82 percent of the silver carp eggs spawned near the Brandon Road Dam would hatch in the Des Plaines River (as close as 1.6 miles downstream from the gates of Brandon Road Lock). Extension of the FluEgg model to include the fate and transport of larvae until gas bladder inflation—the point at which the larvae begin to leave the drift—suggests that eggs spawned at the electric dispersal barrier would reach the gas bladder inflation stage primarily within the Dresden Island Pool, and those spawned at the Brandon Road Dam would reach this stage primarily within the Marseilles and Starved Rock Pools.

  3. Effects of Self-Adjusting File, Mtwo, and ProTaper on the root canal wall

    NARCIS (Netherlands)

    Hin, E.S.; Wu, M.K.; Wesselink, P.R.; Shemesh, H.

    2013-01-01

    Introduction The purpose of this ex vivo study was to observe the incidence of cracks in root dentin after root canal preparation with hand files, self-adjusting file (SAF), ProTaper, and Mtwo. Methods One hundred extracted mandibular premolars with single canals were randomly selected. Two

  4. Cone Beam Computed Tomographic Evaluation and Diagnosis of Mandibular First Molar with 6 Canals

    Directory of Open Access Journals (Sweden)

    Shiraz Pasha

    2016-01-01

    Full Text Available Root canal treatment of tooth with aberrant root canal morphology is very challenging. So thorough knowledge of both the external and internal anatomy of teeth is an important aspect of root canal treatment. With the advancement in technology it is imperative to use modern diagnostic tools such as magnification devices, CBCT, microscopes, and RVG to confirm the presence of these aberrant configurations. However, in everyday endodontic practice, clinicians have to treat teeth with atypical configurations for root canal treatment to be successful. This case report presents the management of a mandibular first molar with six root canals, four in mesial and two in distal root, and also emphasizes the use and importance of Cone Beam Computed Tomography (CBCT as a diagnostic tool in endodontics.

  5. Semicircular canal dehiscence: comparison of T2-weighted turbo spin-echo MRI and CT

    International Nuclear Information System (INIS)

    Krombach, G.A.; Schmitz-Rode, T.; Haage, P.; Guenther, R.W.; DiMartino, E.; Prescher, A.; Kinzel, S.

    2004-01-01

    We assessed the value of MRI for delineation of dehiscence of the superior or posterior semicircular canal, as compared with CT, the current standard study for this entity. We reviewed heavily T2-weighted fast spin-echo images and high-resolution CT of the temporal bones of 185 patients independently semicircular canal dehiscence and its extent. In 30 patients (19 men, 11 women) we identified dehiscence of the bone over the superior and/or posterior semicircular canal on MRI. In 27 of these cases CT also showed circumscribed bone defects. In one patient dehiscence of the superior semicircular canal was initially overlooked on MRI, but seen on CT. MRI imaging thus had a sensitivity of 96% and specificity of 98%. Knowledge of the appearances of this entity on MRI may contribute to early diagnosis in patients with vertigo due to semicircular canal dehiscence. (orig.)

  6. Semicircular canal dehiscence: comparison of T2-weighted turbo spin-echo MRI and CT

    Energy Technology Data Exchange (ETDEWEB)

    Krombach, G.A.; Schmitz-Rode, T.; Haage, P.; Guenther, R.W. [Department of Diagnostic Radiology, University of Technology, Pauwelstrasse 30, 52057, Aachen (Germany); DiMartino, E. [Department of Otorhinolaryngology, University of Technology, Pauwelstrasse 30, 52057, Aachen (Germany); Prescher, A. [Department of Anatomy, University of Technology, Pauwelstrasse 30, 52057, Aachen (Germany); Kinzel, S. [Department of Experimental Veterinary Medicine, University of Technology, Pauwelstrasse 30, 52057, Aachen (Germany)

    2004-04-01

    We assessed the value of MRI for delineation of dehiscence of the superior or posterior semicircular canal, as compared with CT, the current standard study for this entity. We reviewed heavily T2-weighted fast spin-echo images and high-resolution CT of the temporal bones of 185 patients independently semicircular canal dehiscence and its extent. In 30 patients (19 men, 11 women) we identified dehiscence of the bone over the superior and/or posterior semicircular canal on MRI. In 27 of these cases CT also showed circumscribed bone defects. In one patient dehiscence of the superior semicircular canal was initially overlooked on MRI, but seen on CT. MRI imaging thus had a sensitivity of 96% and specificity of 98%. Knowledge of the appearances of this entity on MRI may contribute to early diagnosis in patients with vertigo due to semicircular canal dehiscence. (orig.)

  7. Computed tomography of the spinal canal for the cervical spine and spinal cord injury

    International Nuclear Information System (INIS)

    Kimura, Isao; Niimiya, Hikosuke; Nasu, Kichiro; Shioya, Akihide; Ohhama, Mitsuru

    1983-01-01

    The cervical spinal canal and cervical spinal cord were measured in normal cases and 34 cases of spinal or spinal cord injury. The anteroposterior diameter and area of the normal cervical spinal canal showed a high correlation. The area ratio of the normal cervical spinal canal to the cervical spinal cord showed that the proportion of the cervical spinal cord in the spinal canal was 1/3 - 1/5, Csub(4,5) showing a particularly large proportion. In acute and subacute spinal or spinal cord injury, CT visualized in more details of the spinal canal in cases that x-ray showed definite bone injuries. Computer assisted myelography visualized more clearly the condition of the spinal cord in cases without definite findings bone injuries on x-ray. Demonstrating the morphology of spinal injury in more details, CT is useful for selection of therapy for injured spines. (Chiba, N.)

  8. Cone beam CT findings of retromolar canals: Report of cases and literature review

    Energy Technology Data Exchange (ETDEWEB)

    Han, Sang Sun [Dept. of Dental Hygiene, Eulji University, Seongnam (Korea, Republic of); Park, Chang Seo [Dept. of Oral and Maxillofacial Radiology, College of Dentistry, Yonsei University, Seoul (Korea, Republic of)

    2013-12-15

    A retromolar canal is an anatomical variation in the mandible. As it includes the neurovascular bundle, local anesthetic insufficiency can occur, and an injury of the retromolar canal during dental surgery in the mandible may result in excessive bleeding, paresthesia, and traumatic neuroma. Using imaging analysis software, we evaluated the cone-beam computed tomography (CT) images of two Korean patients who presented with retromolar canals. Retromolar canals were detectable on the sagittal and cross-sectional images of cone-beam CT, but not on the panoramic radiographs of the patients. Therefore, the clinician should pay particular attention to the identification of retromolar canals by preoperative radiographic examination, and additional cone beam CT scanning would be recommended.

  9. Cone beam CT findings of retromolar canals: Report of cases and literature review

    International Nuclear Information System (INIS)

    Han, Sang Sun; Park, Chang Seo

    2013-01-01

    A retromolar canal is an anatomical variation in the mandible. As it includes the neurovascular bundle, local anesthetic insufficiency can occur, and an injury of the retromolar canal during dental surgery in the mandible may result in excessive bleeding, paresthesia, and traumatic neuroma. Using imaging analysis software, we evaluated the cone-beam computed tomography (CT) images of two Korean patients who presented with retromolar canals. Retromolar canals were detectable on the sagittal and cross-sectional images of cone-beam CT, but not on the panoramic radiographs of the patients. Therefore, the clinician should pay particular attention to the identification of retromolar canals by preoperative radiographic examination, and additional cone beam CT scanning would be recommended.

  10. Transcanal endoscopic resection for leiomyoma of the external auditory canal and a review of the literature.

    Science.gov (United States)

    Ikeda, Ryoukichi; Tateda, Masaru; Okoshi, Akira; Morita, Shinkichi; Suzuki, Hiroyoshi; Hashimoto, Sho

    2016-02-01

    Leiomyoma usually originates from the uterus and alimentary tract, but in extremely rare cases leiomyoma can appear in the external auditory canal. Here we present a 37-year-old man with right auricular fullness. Preoperative findings suggested benign tumor or cholesteatoma in the right external auditory canal. We performed total resection using an endoauricular approach with transcanal endoscopic ear surgery. Histopathological and immunohistochemistry examination confirmed the diagnosis of leiomyoma of external auditory canal. Leiomyoma arising from soft tissue, including that in the external auditory canal, is classified into two types: that from the arrectores pilorum muscles and that from the muscle coats of blood vessels. Only four cases of leiomyoma of external auditor canal have been published in the English literature. The other four cases demonstrated vascular leiomyomas. This is the first report of leiomyoma of the EAC arising from arrectores pilorum muscles. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  11. Surveillance of microbial indicators and physicochemical parameters to investigate pollution status of Lahore canal

    International Nuclear Information System (INIS)

    Tahir, A.; Kanwal, F.; Mateen, B.

    2011-01-01

    The Lahore canal is an important watershed in Lahore. The present study was conducted to monitor pollution load of Lahore canal. Surface water was collected from the middle of the canal at four different sites, and analysed for physicochemical parameters (temperature, pH, EC, DO, BOD/sub 5/, turbidity, nitrates, phosphates) and microbial load (bacteria (TVC), total coliform and fungi). Water quality parameters were monitored from May to August at four sites along 17Km long patch. Surface water was collected in the middle of the canal. The results were compared with IWQ guidelines proposed by WWF, Pakistan. Pollution load of Lahore Canal revealed an alarming situation. Water can be used for the irrigation purpose, but only with advanced treatment. (author)

  12. Systems and methods for biometric identification using the acoustic properties of the ear canal

    International Nuclear Information System (INIS)

    Bouchard, A.M.; Osbourn, G.C.

    1998-01-01

    The present invention teaches systems and methods for verifying or recognizing a person's identity based on measurements of the acoustic response of the individual's ear canal. The system comprises an acoustic emission device, which emits an acoustic source signal s(t), designated by a computer, into the ear canal of an individual, and an acoustic response detection device, which detects the acoustic response signal f(t). A computer digitizes the response (detected) signal f(t) and stores the data. Computer-implemented algorithms analyze the response signal f(t) to produce ear-canal feature data. The ear-canal feature data obtained during enrollment is stored on the computer, or some other recording medium, to compare the enrollment data with ear-canal feature data produced in a subsequent access attempt, to determine if the individual has previously been enrolled. The system can also be adapted for remote access applications. 5 figs

  13. Systems and methods for biometric identification using the acoustic properties of the ear canal

    Science.gov (United States)

    Bouchard, Ann Marie; Osbourn, Gordon Cecil

    1998-01-01

    The present invention teaches systems and methods for verifying or recognizing a person's identity based on measurements of the acoustic response of the individual's ear canal. The system comprises an acoustic emission device, which emits an acoustic source signal s(t), designated by a computer, into the ear canal of an individual, and an acoustic response detection device, which detects the acoustic response signal f(t). A computer digitizes the response (detected) signal f(t) and stores the data. Computer-implemented algorithms analyze the response signal f(t) to produce ear-canal feature data. The ear-canal feature data obtained during enrollment is stored on the computer, or some other recording medium, to compare the enrollment data with ear-canal feature data produced in a subsequent access attempt, to determine if the individual has previously been enrolled. The system can also be adapted for remote access applications.

  14. Root anatomy and canal configuration of the permanent mandibular first molar: clinical implications and recommendations.

    Science.gov (United States)

    de Pablo, Oliver Valencia; Estevez, Roberto; Heilborn, Carlos; Cohenca, Nestor

    2012-01-01

    Root canal anatomy may present clinicians with a complex clinical challenge that requires diagnostic approaches, access modification, and clinical skills to successfully localize, negotiate, disinfect, and seal the root canal system. This article discusses the clinical implications of endodontic therapy on permanent mandibular first molars. The number of roots on the mandibular first molar is directly related to ethnicity. Canal morphology has a significant effect on treatment protocol: Mesial roots present two canals on a regular basis, adopting 2-2 and 2-1 as the most common configurations. A third canal is present in 2.6% of the population. The most common configuration in the distal root is type I (62.7%), followed by type II (14.5%) and type IV (12.4%). Diagnosis and treatment of complex root canal systems often require specialized training that may be beyond the scope of the average general practitioner. Access modifications are required to find extra roots and/or canals. The instrumentation of the third root requires a different access and small, flexible instruments, given the curvature that is usually present buccally in the apical third. The incidence of isthmuses is 55% in the mesial root and 20% in the distal root. This anatomical configuration should be taken into consideration during endodontic treatment as well as during periapical surgery.

  15. The Suez Canal as a habitat and pathway for marine algae and seagrasses

    Science.gov (United States)

    Aleem, A. A.

    The Suez Canal supports a diversified benthic algal flora; 133 species of benthic algae are now known from the Canal, as compared with only 24 in 1924. The vertical and horizontal distribution of algae is considered in relation to hydrographic factors. The algae display zonation and 3-4 algal belts are distinguished on the Canal banks on buoys and pier supports. Associated fauna include Balanus amphitrite and Brachidontes variabilis, together with various hydroids, sponges, ascidians, asteroids, ophiuroids and crustaceans. Merceriella enigmatica thrives well in brackish water habitats. The algal flora in the Bitter Lakes resembles that in the Red Sea. The number of Red Sea species decreases from Suez to Port Said in the littoral zone. On the other hand, bottom algae predominantly belong to Red Sea flora. Thirty of the species of algae found belong to the Indo-Pacific flora; half of these are new records to the Canal. Several of these Indo-Pacific algae have recently become established in the Eastern Mediterranean, whereas only two of the Mediterranean macro-algal flora (viz. Caulerpa prolifera and Halopteris scoparia) have been found in the Gulf of Suez. Two seagrasses, Halopia ovalis and Thalassia hemprichii, are recorded for the first time in the Canal. Only Halophila stipulacea has found its way into the Mediterranean via the Suez Canal, but none of the Mediterranean seagrasses is found either in the Canal or in the Red Sea.

  16. Comparative evaluation of fracture and defect in reciproc and rotary files in severe curved root canals

    Directory of Open Access Journals (Sweden)

    Mahdis Bagherian

    2015-03-01

    Full Text Available Introduction: Root canal instrumentation is an important phase in root canal therapy. Since success in endodontic treatment depends on file defect and fracture, the aim of this study was to compare the evaluation of defect and fracture in rotary and reciproc files in severe curved root canals. Materials & Methods: In this experimental study, 60 mesial canals of human closed apex molars with more than 30° canal curvature were randomly divided into two groups. In first group M-two rotary files number# 15, 20, and 25 and in second group R25 reciproc file were used for filing, respectively. A ×8 magnifier was applied to evaluate the defect or fracture presence in each side and if it were observed, a new file would be replaced. Therefore, the number of prepared canals with each file and fractured or defective files and the place of fracture in root canal were recorded. Kaplan Meier curve and log rank test were done by using SPSS v.22. Results: In rotary group, seven and two files were fractured and defected, respectively and four files were fractured and no defect was observed in reciproc group. Although the mean of the number of prepared canals until fracture or defect in rotary and reciproc groups was 3.3 and 7.06, respectively, there were no significant differences between two systems. All file’s fractures occurred in apical regions . Conclusion: The results showed that there was no significant difference in defects or fractures of rotary and reciproc systems. Reciproc instruments can be more effective than rotary ones because the root canal preparation in rotary instruments is longer than in reciproc system.

  17. Effects of canal enlargement and irrigation needle depth on the cleaning of the root canal system at 3 mm from the apex

    Directory of Open Access Journals (Sweden)

    Ho-Jin Moon

    2012-02-01

    Full Text Available Objectives The aim of this study was to test the hypothesis, that the effectiveness of irrigation in removing smear layer in the apical third of root canal system is dependent on the depth of placement of the irrigation needle into the root canal and the enlargement size of the canal. Materials and Methods Eighty sound human lower incisors were divided into eight groups according to the enlargement size (#25, #30, #35 and #40 and the needle penetration depth (3 mm from working length, WL-3 mm and 9 mm from working length, WL-9 mm. Each canal was enlarged to working length with Profile.06 Rotary Ni-Ti files and irrigated with 5.25% NaOCl. Then, each canal received a final irrigation with 3 mL of 3% EDTA for 4 min, followed by 5 mL of 5.25% NaOCl at different level (WL-3 mm and WL-9 mm from working length. Each specimen was prepared for the scanning electron microscope (SEM. Photographs of the 3mm area from the apical constriction of each canal with a magnification of ×250, ×500, ×1,000, ×2,500 were taken for the final evaluation. Results Removal of smear layer in WL-3 mm group showed a significantly different effect when the canal was enlarged to larger than #30. There was a significant difference in removing apical smear layer between the needle penetration depth of WL-3 mm and WL-9 mm. Conclusions Removal of smear layer from the apical portion of root canals was effectively accomplished with apical instrumentation to #35/40 06 taper file and 3 mm needle penetration from the working length.

  18. The cochlear nerve canal and internal auditory canal in children with normal cochlea but cochlear nerve deficiency

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Fei; Li, Jianhong; Xian, Junfang; Wang, Zhenchang [Dept. of Radiology, Beijing Tongren Hospital, Capital Medical Univ., Beijing (China)], e-mail: cjr.wzhch@vip.163.com; Mo, Lingyan [Dept. of Otorhinolaryngology, Beijing Tongren Hospital, Capital Medical Univ., Beijing (China)

    2013-04-15

    Background: There is an increasing frequency of requests for cochlear implantation (CI) in deaf children and more detailed image information is necessary for selecting appropriate candidates. Cochlear nerve deficiency (CND) is a contraindication to CI. Magnetic resonance imaging (MRI) has been used to evaluate the integrity of the cochlear nerve. The abnormalities of the cochlear nerve canal (CNC) and internal auditory canal (IAC) have been reported to be associated with CND. Purpose: To correlate CNC manifestation, size, and IAC diameter on high-resolution CT (HRCT) with CND diagnosed by MRI in children. Material and Methods: HRCT images from 35 sensorineurally deaf children who had normal cochlea but bilateral or unilateral CND diagnosed by MRI were studied retrospectively. The CNC and IAC manifestation and size were assessed and correlated with CND. Results: CND was diagnosed by MRI in 54/70 ears (77.1%). Thirty-two ears had an absent cochlear nerve (59.3%), while 22 ears had a small cochlear nerve (40.7%). The CNC diameter was <1.5 mm in 36 ears (66.7%). The CNC diameter ranged between 1.5 and 2.0 mm in seven ears (13.0%) and was >2.0 mm in 11 ears (20.4%). The IAC diameter was <3.0 mm in 25 ears (46.3%) and >3.0 mm in 29 ears (53.7%). Conclusion: The hypoplastic CNC might be more highly indicative of CND than that of a narrow IAC.

  19. Clinical characteristics of keratosis obturans and external auditory canal cholesteatoma.

    Science.gov (United States)

    Park, So Young; Jung, Young Hoon; Oh, Jeong-Hoon

    2015-02-01

    Keratosis obturans (KO) and external auditory canal cholesteatoma (EACC) have been considered separate entities. While the disorders are distinct, they share many overlapping characteristics, making a correct diagnosis difficult. In the present study, we compared their clinical characteristics and radiological features to clarify the diagnostic criteria. Retrospective case series. Academic medical center. The clinical data of 23 cases of EACC and KO were retrospectively reviewed. The following clinical characteristics were compared between the 2 groups: sex, age, onset of symptoms, follow-up period, audiometric results, and imaging findings on temporal bone computed tomography including bilaterality, location, and the presence of extension to adjacent tissue. The mean age of the EACC group was significantly older than that of the KO group. All of the cases of EACC occurred unilaterally, and bilateral occurrences of KO were observed in 4 of 9 cases. All of the lesions in the KO group were circumferential, and no lesion in the EACC group invaded the superior canal wall. No significant differences in symptoms, such as acute otalgia, otorrhea, and hearing loss, were noted between the 2 groups. The incidence of conductive hearing impairment more than 10 dB was higher in the KO group than in the EACC group. Thus, KO and EACC are 2 distinct disease entities that share common features in clinical characteristics except for predominant age and bilaterality. Conservative treatment with meticulous cleaning of the lesion was successful in most cases with a long-term follow-up. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2014.

  20. Effect of canal length and curvature on working length alteration with WaveOne reciprocating files.

    Science.gov (United States)

    Berutti, Elio; Chiandussi, Giorgio; Paolino, Davide Salvatore; Scotti, Nicola; Cantatore, Giuseppe; Castellucci, Arnaldo; Pasqualini, Damiano

    2011-12-01

    This study evaluated the working length (WL) modification after instrumentation with WaveOne Primary (Dentsply Maillefer, Ballaigues, Switzerland) reciprocating files and the incidence of overinstrumentation in relation to the initial WL. Thirty-two root canals of permanent teeth were used. The angles of curvature of the canals were calculated on digital radiographs. The initial WL with K-files was transferred to the matched WaveOne Primary reciprocating files. After glide paths were established with PathFile (Dentsply Maillefer, Ballaigues, Switzerland), canals were shaped with WaveOne Primary referring to the initial WL. The difference between the postinstrumentation canal length and the initial canal length was analyzed by using a fiberoptic inspection microscope. Data were analyzed with a balanced 2-way factorial analysis of variance (P < .05). Referring to the initial WL, 24 of 32 WaveOne Primary files projected beyond the experimental apical foramen (minimum-maximum, 0.14-0.76 mm). A significant decrease in the canal length after instrumentation (95% confidence interval ranging from -0.34 mm to -0.26 mm) was detected. The canal curvature significantly influenced the WL variation (F(1) = 30.65, P < .001). The interaction between the initial canal length and the canal curvature was statistically significant (F(2) = 4.38, P = .014). Checking the WL before preparation of the apical third of the root canal is recommended when using the new WaveOne NiTi single-file system. Copyright © 2011 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  1. The cochlear nerve canal and internal auditory canal in children with normal cochlea but cochlear nerve deficiency

    International Nuclear Information System (INIS)

    Yan, Fei; Li, Jianhong; Xian, Junfang; Wang, Zhenchang; Mo, Lingyan

    2013-01-01

    Background: There is an increasing frequency of requests for cochlear implantation (CI) in deaf children and more detailed image information is necessary for selecting appropriate candidates. Cochlear nerve deficiency (CND) is a contraindication to CI. Magnetic resonance imaging (MRI) has been used to evaluate the integrity of the cochlear nerve. The abnormalities of the cochlear nerve canal (CNC) and internal auditory canal (IAC) have been reported to be associated with CND. Purpose: To correlate CNC manifestation, size, and IAC diameter on high-resolution CT (HRCT) with CND diagnosed by MRI in children. Material and Methods: HRCT images from 35 sensorineurally deaf children who had normal cochlea but bilateral or unilateral CND diagnosed by MRI were studied retrospectively. The CNC and IAC manifestation and size were assessed and correlated with CND. Results: CND was diagnosed by MRI in 54/70 ears (77.1%). Thirty-two ears had an absent cochlear nerve (59.3%), while 22 ears had a small cochlear nerve (40.7%). The CNC diameter was 2.0 mm in 11 ears (20.4%). The IAC diameter was 3.0 mm in 29 ears (53.7%). Conclusion: The hypoplastic CNC might be more highly indicative of CND than that of a narrow IAC

  2. Comparison of canal transportation and centering ability of hand Protaper files and rotary Protaper files by using micro computed tomography

    OpenAIRE

    Amit Gandhi; Taru Gandhi

    2011-01-01

    Introduction and objective: The aim of the present study was to compare root canal preparation with rotary ProTaper files and hand ProTaper files to find a better instrumentation technique for maintaining root canal geometry with the aid of computed tomography. Material and methods: Twenty curved root canals with at least 10 degree of curvature were divided into 2 groups of 10 teeth each. In group I the canals were prepared with hand ProTaper files and in group II the canals were prepared wit...

  3. Endoscopic root canal treatment.

    Science.gov (United States)

    Moshonov, Joshua; Michaeli, Eli; Nahlieli, Oded

    2009-10-01

    To describe an innovative endoscopic technique for root canal treatment. Root canal treatment was performed on 12 patients (15 teeth), using a newly developed endoscope (Sialotechnology), which combines an endoscope, irrigation, and a surgical microinstrument channel. Endoscopic root canal treatment of all 15 teeth was successful with complete resolution of all symptoms (6-month follow-up). The novel endoscope used in this study accurately identified all microstructures and simplified root canal treatment. The endoscope may be considered for use not only for preoperative observation and diagnosis but also for active endodontic treatment.

  4. Effects of liquid- and paste-type EDTA on smear-layer removal during rotary root-canal instrumentation

    Directory of Open Access Journals (Sweden)

    Gin Chen

    2011-03-01

    Conclusions: The use of paste/gel-type chelators during rotary nickel–titanium instrumentation resulted in improved cleanliness in the coronal and middle parts of the root canal. We recommend using liquid EDTA as a final flushing solution during root-canal preparation because it provides a better smear layer-free condition before 3-dimensional root-canal obturation.

  5. Bank erosion of navigation canals in the western and central Gulf of Mexico

    Science.gov (United States)

    Thatcher, Cindy A.; Hartley, Stephen B.; Wilson, Scott A.

    2011-01-01

    Erosion of navigation canal banks is a direct cause of land loss, but there has been little quantitative analysis to determine why certain major canals exhibit faster widening rates (indicative of erosion) than others in the coastal zones of Texas, Louisiana, Mississippi, and Alabama. We hypothesize that navigation canals exhibit varying rates of erosion based on soil properties of the embankment substrate, vegetation type, geologic region (derived from digital versions of state geologic maps), and the presence or absence of canal bank armaments (that is, rock rip-rap, concrete bulkheads, or other shoreline protection structures). The first objective of this project was to map the shoreline position and substrate along both banks of the navigation canals, which were digitized from 3 different time periods of aerial photography spanning the years of 1978/79 to 2005/06. The second objective was to quantify the erosion rates of the navigation canals in the study area and to determine whether differences in erosion rates are related to embankment substrate, vegetation type, geologic region, or soil type. To measure changes in shoreline position over time, transects spaced at 50-m (164-ft) intervals were intersected with shorelines from all three time periods, and an annual rate of change was calculated for each transect. Mean annual rates of shoreline change ranged from 1.75 m/year (5.74 ft/year) on the west side of the Atchafalaya River, La., where there was shoreline advancement or canal narrowing, to -3.29 m/year (-10.79 ft/year) on the south side of the Theodore Ship Channel, Ala., where there was shoreline retreat or erosion. Statistical analysis indicated that there were significant differences in shoreline retreat rates according to geologic region and marsh vegetation type, and a weak relationship with soil organic content. This information can be used to better estimate future land loss rates associated with navigation canals and to prioritize the location of

  6. Mines and Underwater IEDs in U.S. Ports and Waterways: Context, Threats, Challenges, and Solutions

    National Research Council Canada - National Science Library

    Truver, Scott C

    2008-01-01

    .... The threats of the Cold War are gone, and the United States finds itself operating in an environment where piracy, illegal migration, drug smuggling, terrorism, arms proliferation, and environmental...

  7. Mines and Underwater IEDs in U.S. Ports and Waterways: Context, Threats, Challenges, and Solutions

    National Research Council Canada - National Science Library

    Truver, Scott C

    2008-01-01

    .... Under the cloak of legal activity, groups that would do the United States harm can enter the U.S. homeland anywhere along more than 95,000 miles of coastlines and through some 360 ports from Maine to Guam...

  8. Evaluation of Root and Canal Morphology of Mandibular First Molars: A Clearing Method in an Iranian Population

    Directory of Open Access Journals (Sweden)

    Shirkavand

    2016-07-01

    Full Text Available Background Successful endodontic treatment is dependent on the knowledge of root canal anatomy. Objectives This study aims to investigate the root canal anatomy of mandibular first molars in an Iranian population. Materials and Methods One hundred human mandibular first molars were collected and stored in 5.25% NaOCl. Radiographic images of the teeth were taken in mesial, distal, and buccal aspects using digital radiography. The root numbers were recorded, and the teeth were covered with lacquer. Access cavities were prepared, pulp tissue was dissolved, the apex was covered with liquid glue, and the root canals were injected with methylene blue. Decalcification of the teeth meant they were kept in 10% nitric acid, and final dehydration meant they were kept in 100% Isopropyl alcohol for 72 hours and rendered clear by immersion in methyl salicylate. The number of root canals per tooth, the number of canals per root, and canal configuration in each tooth were recorded. Results Ninety-nine of the 100 teeth had two roots and the other had three roots. The teeth were classified based on the number of canals; there were 2% with two canals, 59% with three canals, and 39% with four canals. Based on the Vertucci classification, the most prevalent canal configurations in the mesial root were types II and IV, and type I in the distal root. Conclusions The most common root morphology is the two rooted morphology with three canals. Both the mesial and distal roots show wide variations in canal anatomy with type IV and type I canal configuration predominating in the mesial and distal roots, respectively. Iranian mandibular first molar teeth exhibit features close to the average Caucasian, Jordanian, and Kuwaiti’s root and canal morphology.

  9. 3001 canal radiological characterization and waste removal report, Oak Ridge National Laboratory, Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    Ritchie, M.G.

    1996-12-01

    An underground steel reinforced concrete transfer and storage canal was built in 1943 and operated as an integral part of the Oak Ridge Graphite Reactor Building (3001) until 1963 when the reactor was shutdown. During operation, the canal was used for under water transfer of irradiated materials and other metals from the reactor in Building 3001 to the Building 3019 hot cell for further processing. After shutdown of the reactor, the canal was used for storage of irradiated materials and fission products until 1990 when the larger materials were removed and stored in the Department of Energy (DOE) approved solid waste management storage facilities. At that time it was discovered that a considerable amount of sludge had accumulated over the intervening years and subsequent analysis showed that the sludge contained Resource Conservation and Recovery Act (RCRA) materials that violated quantities allowed by the RCRA regulations. It was also recognized in 1990 that the canal was losing water to evaporation and the ground at the rate of approximately 400 gallons per day. To maintain water quality; i.e., radionuclide content at or near DOE derived concentration guidelines (DCG), the water in the canal is constantly demineralized using a demineralizer in the Building 3001 and demineralized make up water is supplied from the Building 3004 demineralizer. This report summarizes the 301 Canal Cleanup Task and the solid waste removed from the 3001 Canal in 1996

  10. A study of angle of mandibular canal and mental foramen on the panoramic radiograph

    International Nuclear Information System (INIS)

    Choi, Hang Moon

    2009-01-01

    To assessment the angle between mandibular canal and occlusal plane at each posterior tooth region and location of mental foramen on the panoramic radiographs. This study analysed 46 half-mandibles of panoramic radiographs. Inferior border of mandibular canal was traced. Occlusal plane was drawn from lingual cusp tip of the first premolar to distolingual cusp tip of the second molar. Perpendicular line from occlusal plane was drawn at each tooth region and then tangential lines were drawn from the crossing points at canal. The angle between occlusal plane and tangential line was measured. The location of mental foramen was also studied. According to the location of mental foramen, radiographs were divided into M (mesial) group and D (distal) group on the basis of the second premolar. and then inter-group analysis about mandibular canal angle was done. The angles of mandibular canals were -17.7 .deg. C, -9.5 .deg. C, 8.2 .deg. C, 22.3 .deg. C, and 39.2 .deg. C at first premolar, second premolar, first molar, second molar, and third molar, respectively. The commonest position of the mental foramen was distal to the second premolar. Inter-group comparison showed statistically significant difference at the second premolar and the first molar (p<0.001). The acknowledgement of mandibular canal angulation and location of mental foramen can help understanding the course of mandibular canal.

  11. The Use of Lasers in Disinfection and Cleaning of Root Canals: a Review

    Directory of Open Access Journals (Sweden)

    Ivica Anić

    2014-01-01

    Full Text Available The outcome of root canal treatment is based on efficient disinfection of the root canal system and prevention of reinfection. Current chemomechanical cleaning methods do not always achieve these goals, and insufficient root canal disinfection is the main reason for endodontic failure. Due to high energy content and specific characteristics of laser light, laser treatment has been proposed for cleaning and disinfecting the root canal system. This paper reviews the literature covering the effect of Er:YAG, Er,Cr:YSGG, Nd:YAG and diode laser on the root canal wall in the removal of smear layer and against intracanal bacteria. Recently, the use of laser energy to induce cavitation and acoustic streaming of intracanal irrigants has been investigated. Based on recent literature, it can be concluded that lasers have bactericidal effects. However, they still cannot replace sodium hypochlorite and should be considered as an adjunct to the current chemical root canal disinfection protocols. Certain lasers can help in removing the smear layer and debris and can modify the morphology of the root canal wall. Unfortunately, there have not been enough randomized clinical studies evaluating endodontic treatment outcome following the use of laser.

  12. An in vitro comparison of root canal transportation by reciproc file with and without glide path.

    Science.gov (United States)

    Nazarimoghadam, Kiumars; Daryaeian, Mohammad; Ramazani, Nahid

    2014-09-01

    The aim of ideal canal preparation is to prevent iatrogenic aberrations such as transportation. The aim of this study was to evaluate the root canal transportation by Reciproc file with and without glide path. Thirty acrylic-resin blocks with a curvature of 60° and size#10 (2% taper) were assigned into two groups (n= 15). In group 1, the glide path was performed using stainless steel k-files size#10 and 15 at working length In group 2, canals were prepared with Reciproc file system at working length. By using digital imaging software (AutoCAD 2008), the pre-instrumentation and post-instrumentation digital images were superimposed over, taking the landmarks as reference points. Then the radius of the internal and external curve of the specimens was calculated at three α, β and γ points (1mm to apex as α, 3mm to apex as β, and 5mm to apex as γ). The data were statically analyzed using the independent T-test and Mann-Whitney U test by SPSS version 16. Glide path was found significant for only external curve in the apical third of the canal; that is, 5mm to apex (P=0.005). But in the other third, canal modification was not significant (P> 0.008). Canal transportation in the apical third of the canal seems to be significantly reduced when glide path is performed using reciprocating files.

  13. Study of mastoid canals and grooves in north karnataka human skulls.

    Science.gov (United States)

    Hadimani, Gavishiddappa Andanappa; Bagoji, Ishwar Basavantappa

    2013-08-01

    This study was undertaken to observe the frequency of mastoid canals and grooves in north Karnataka dry human skulls. 100 dry human skulls of unknown age and sex from the department of Anatomy were selected and observed for the present study. The mastoid regions of dry skulls were observed for the presence of mastoid canals and grooves, if any. A metallic wire was passed through the canal for its confirmation and then the length was measured. The Mastoid canals were present in 53% of the total 100 skulls observed either bilaterally or unilaterally. Mastoid grooves were present in 18% of the total skulls (100) observed. Double mastoid canal was found in 01% of total skull studied and both Mastoid canals & Mastoid grooves together were present in 02% of the total skulls (100) observed. The knowledge of mastoid canals and grooves is very important for otolaryngologists and neurosurgeons. Because they contain an arterial branch of occipital artery with its accompanying vein which is liable to injury resulting into severe bleeding.

  14. Lingual Foramina and Canals of the Mandible: Anatomic Variations in a Lebanese Population

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    Georges Aoun

    2017-01-01

    Full Text Available Objective: The aim of this study was to evaluate the mandibular lingual foramina (LF and canals and their anatomic variations using cone-beam computed tomography (CBCT technology in a Lebanese population. Materials and Methods: In this study, we analyzed CBCT images of 90 adult Lebanese patients (41 males and 49 females. We assessed the number and location of the LF. In additional, we measured: (a The distance from both the alveolar crest and the inferior border of the mandible to the LF and (b the length of the lingual canals (LCs. The data obtained was analyzed statistically using Shapiro–Wilk normality test, t-test, Chi-square, and Fisher's exact tests. Statistical significance was set at 0.05. Results: In our sample, the LF and canals were present in 93.33% of the CBCT analyzed, and the majority (76.64% was located above the genial tubercles. The distance from the foramen of the superior and the inferior LCs to the alveolar crest was 16.24 ± 2.82 mm and 25.49 ± 2.43 mm, respectively. The distance from the foramen of the superior canal to the inferior border of the mandible was 14 ± 2.32 mm. The mean length of the superior canal was 5.81 ± 1.6 mm and 4.25 ± 1.2 mm for the inferior one. There were no gender-related differences in the anatomic characteristics of the LF and canals except for the distance measured from the superior canal foramina to the alveolar crest where the measurement was significantly greater in males compared to females. Neither the number of canals nor the positions of the foramina were different between males and females. Conclusion: Within the limits of this study, we concluded that in our sample of Lebanese adults, there was substantial variability in the LF and canals anatomy and location.

  15. Trifid nasopalatine canal: case report of a rare anatomical variation and its surgical implications

    International Nuclear Information System (INIS)

    Guanaes Gomes Torres, Marianna; Crusoé-Rebello, Margarida Iêda; Faro Valverde, Ludmila de; Torres Andion Vidal, Manuela

    2016-01-01

    The nasopalatine canal is a long slender structure present in the midline of the anterior maxilla that connects the palate to the floor of the nasal cavity. The nasopalatine canal contains the nasopalatine nerve, the terminal branch of the nasopalatine artery, fibrous connective tissue, adipose tissue, and minor salivary glands. The purpose of this article was to report a case of a trifid nasopalatine canal detected by cone beam computed tomography prior to dental implant placement. A 47-year-old female patient was submitted to cone beam computed tomography. Axial and sagittal sections revealed a trifurcation of the nasopalatine canal. Each canal was separated from the other by bony septa and extended independently from the floor of the nasal cavity to the incisive foramen in the remnant of the alveolar process in the anterior region of the maxilla. Cone beam computed tomography has permitted better visualization of the details and anatomical variations of the nasopalatine canal. Detailed knowledge of variations in the shape, number and size of the nasopalatine canal is fundamental for surgical procedures, such as local anesthesia in the anterior maxillary region and placement of dental implants, in order to prevent damage to important arteries and nerves. (author)

  16. Anatomy and morphology of the nasopalatine canal using cone-beam computed tomography

    International Nuclear Information System (INIS)

    Thakur, Arpita Rai; Burde, Krishna; Guttai, Kruthika; Naikmasu, Venkatesh

    2013-01-01

    This study was performed to evaluate the general anatomy and morphology of the nasopalatine canal using cone-beam computed tomography (CBCT) and to determine the human anatomic variability of the nasopalatine canal in relation to age and gender. The study included 100 subjects aged between 20 and 86 years who were divided into the following 3 groups: 1) 20-34 years old; 2) 35-49 years old; 3) ≥50 years old. The subjects were equally distributed between the genders. CBCT was performed using a standard exposure and patient positioning protocol. The data of the CBCT images were sliced in three dimensions. Image planes on the three axes (X, Y, and Z) were sequentially analyzed for the location, morphology and dimensions of the nasopalatine canal by two independent observers. The correlation of age and gender with all the variables was evaluated. The present study did not reveal statistically significant differences in the number of openings at the nasal fossa; diameter of the nasal fossa openings; diameter of the incisive fossa; shape, curvature, and angulation of the canal as viewed in the sagittal sections; antero-posterior dimensions and length of the canal in the sagittal sections; or the level of division of the canal in the coronal plane by age. However, males and females showed significant differences in the length of the canal in the sagittal sections and level of the division of the canal in the coronal plane. The present study highlighted important variability observed in the anatomy and morphology of the nasopalatine canal.

  17. Anatomy and morphology of the nasopalatine canal using cone-beam computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Thakur, Arpita Rai [Dept. of Oral Medicine and Radiology, Faculty of Dentistry, Jamia Millia Islamia University, New Delhi (India); Burde, Krishna; Guttai, Kruthika; Naikmasu, Venkatesh [Dept. of Oral Medicine and Radiology, S.D.M. College of Dental Sciences and Hospital, Dharwad (India)

    2013-12-15

    This study was performed to evaluate the general anatomy and morphology of the nasopalatine canal using cone-beam computed tomography (CBCT) and to determine the human anatomic variability of the nasopalatine canal in relation to age and gender. The study included 100 subjects aged between 20 and 86 years who were divided into the following 3 groups: 1) 20-34 years old; 2) 35-49 years old; 3) ≥50 years old. The subjects were equally distributed between the genders. CBCT was performed using a standard exposure and patient positioning protocol. The data of the CBCT images were sliced in three dimensions. Image planes on the three axes (X, Y, and Z) were sequentially analyzed for the location, morphology and dimensions of the nasopalatine canal by two independent observers. The correlation of age and gender with all the variables was evaluated. The present study did not reveal statistically significant differences in the number of openings at the nasal fossa; diameter of the nasal fossa openings; diameter of the incisive fossa; shape, curvature, and angulation of the canal as viewed in the sagittal sections; antero-posterior dimensions and length of the canal in the sagittal sections; or the level of division of the canal in the coronal plane by age. However, males and females showed significant differences in the length of the canal in the sagittal sections and level of the division of the canal in the coronal plane. The present study highlighted important variability observed in the anatomy and morphology of the nasopalatine canal.

  18. First branchial cleft sinus presenting with cholesteatoma and external auditory canal atresia.

    Science.gov (United States)

    Yalçin, Sinasi; Karlidağ, Turgut; Kaygusuz, Irfan; Demirbağ, Erhan

    2003-07-01

    First branchial cleft abnormalities are rare. They may involve the external auditory canal and middle ear. We describe a 6-year-old girl with congenital external auditory canal atresia, microtia, and cholesteatoma of mastoid and middle ear in addition to the first branchial cleft abnormalities. Clinical features of the patient are briefly described and the embryological relationship between first branchial cleft anomaly and external auditory canal atresia is discussed. The surgical management of these lesions may be performed, both the complete excision of the sinus and reconstructive otologic surgery.

  19. Physicochemical Properties, Contamination and Suitability of Canal Water for Irrigation, Lahore Branch Pakistan

    Directory of Open Access Journals (Sweden)

    Tayyaba Aftab

    2011-12-01

    Full Text Available The pollution status of Lahore branch canal was determined by physical, chemical and metal constituents because the water is used for irrigation of lands in and around the city. The average result of each physical, chemical and metal parameter at 12 different sites (Location-1 to Location-12 of Lahore branch canal was compared with Food and Agricultural organization (FAO. All physical and chemical parameters were within standards limit while metals concentrations were found in variable quantities in canal water samples. cadmium, copper and chromium concentration was found much higher than the permissible FAO standards.

  20. Semicircular canals in Anolis lizards: ecomorphological convergence and ecomorph affinities of fossil species.

    Science.gov (United States)

    Dickson, Blake V; Sherratt, Emma; Losos, Jonathan B; Pierce, Stephanie E

    2017-10-01

    Anoli s lizards are a model system for the study of adaptive radiation and convergent evolution. Greater Antillean anoles have repeatedly evolved six similar forms or ecomorphs: crown-giant, grass-bush, twig, trunk, trunk-crown and trunk-ground. Members of each ecomorph category possess a specific set of morphological, ecological and behavioural characteristics which have been acquired convergently. Here we test whether the semicircular canal system-the organ of balance during movement-is also convergent among ecomorphs, reflecting the shared sensory requirements of their ecological niches. As semicircular canal shape has been shown to reflect different locomotor strategies, we hypothesized that each Anolis ecomorph would have a unique canal morphology. Using three-dimensional semilandmarks and geometric morphometrics, semicircular canal shape was characterized in 41 Anolis species from the Greater Antilles and the relationship between canal shape and ecomorph grouping, phylogenetic history, size, head dimensions, and perch characteristics was assessed. Further, canal morphology of modern species was used to predict the ecomorph affinity of five fossil anoles from the Miocene of the Dominican Republic. Of the covariates tested, our study recovered ecomorph as the single-most important covariate of canal morphology in modern taxa; although phylogenetic history, size, and head dimensions also showed a small, yet significant correlation with shape. Surprisingly, perch characteristics were not found to be significant covariates of canal shape, even though they are important habitat variables. Using posterior probabilities, we found that the fossil anoles have different semicircular canals shapes to modern ecomorph groupings implying extinct anoles may have been interacting with their Miocene environment in different ways to modern Anolis species.

  1. Semicircular canals in Anolis lizards: ecomorphological convergence and ecomorph affinities of fossil species

    Science.gov (United States)

    Dickson, Blake V.; Sherratt, Emma; Losos, Jonathan B.; Pierce, Stephanie E.

    2017-10-01

    Anolis lizards are a model system for the study of adaptive radiation and convergent evolution. Greater Antillean anoles have repeatedly evolved six similar forms or ecomorphs: crown-giant, grass-bush, twig, trunk, trunk-crown and trunk-ground. Members of each ecomorph category possess a specific set of morphological, ecological and behavioural characteristics which have been acquired convergently. Here we test whether the semicircular canal system-the organ of balance during movement-is also convergent among ecomorphs, reflecting the shared sensory requirements of their ecological niches. As semicircular canal shape has been shown to reflect different locomotor strategies, we hypothesized that each Anolis ecomorph would have a unique canal morphology. Using three-dimensional semilandmarks and geometric morphometrics, semicircular canal shape was characterized in 41 Anolis species from the Greater Antilles and the relationship between canal shape and ecomorph grouping, phylogenetic history, size, head dimensions, and perch characteristics was assessed. Further, canal morphology of modern species was used to predict the ecomorph affinity of five fossil anoles from the Miocene of the Dominican Republic. Of the covariates tested, our study recovered ecomorph as the single-most important covariate of canal morphology in modern taxa; although phylogenetic history, size, and head dimensions also showed a small, yet significant correlation with shape. Surprisingly, perch characteristics were not found to be significant covariates of canal shape, even though they are important habitat variables. Using posterior probabilities, we found that the fossil anoles have different semicircular canals shapes to modern ecomorph groupings implying extinct anoles may have been interacting with their Miocene environment in different ways to modern Anolis species.

  2. Guided Endodontics: a novel treatment approach for teeth with pulp canal calcification and apical pathology.

    Science.gov (United States)

    Krastl, Gabriel; Zehnder, Marc S; Connert, Thomas; Weiger, Roland; Kühl, Sebastian

    2016-06-01

    To present a new treatment approach for teeth with pulp canal calcification (PCC) which require root canal treatment. A 15-year-old male patient presented with pain of his upper right central incisor. The tooth showed signs of apical periodontitis. Due to PCC, location of the root canal was judged to be difficult and associated with a high risk of perforation. A cone beam computed tomography (CBCT) and an intra-oral surface scan were performed and matched using software for virtual implant planning. After planning the position of the drill for root canal location, a virtual template was designed, and the data were exported as an STL file and sent to a 3D printer for template fabrication. The template was positioned on the anterior maxillary teeth. A specific drill was used to penetrate through the obliterated part of the root canal and obtain minimally invasive access to the apical part. The root canal was accessible at 9 mm distance from the apex. Further root canal preparation was carried out using an endodontic rotary instrumentation system. After an interappointment dressing for 4 weeks, the root canal was filled with vertically condensed gutta-percha using an epoxy sealer. The access cavity was restored with a composite material. After 15 months, the patient was clinically asymptomatic with no pain on percussion. The radiograph showed no apical pathology. The presented guided endodontic approach seems to be a safe, clinically feasible method to locate root canals and prevent root perforation in teeth with PCC. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  3. The distributions of chemical elements and Caesium-137 in the Northern-Crimean canal ecosystem

    International Nuclear Information System (INIS)

    Lazorenko, G.

    1998-01-01

    The distributions in 1992-1995 of some chemical elements and 137 Cs concentrations in components of the Northern-Crimean Canal (NCC) ecosystem and agricultural fields of the Kherson District and the Northern Crimea irrigated by the Dnieper River water are presented in the work. Five main sampling were selected between the Kakhovka Reservior (at the beginning of the NCC) and the Karkinitsky Bay along the 150 km of the main Canal. Two additional stations were selected in discharge canals to study of the role of irrigated agricultural fields in the accumulation of 137 Cs and chemical elements from water. (author)

  4. Canal rays

    International Nuclear Information System (INIS)

    Goldstein, Eugen

    2010-01-01

    For more than fifty years the German physicist Eugen Goldstein was engaged in an obscure fringe field of physics, on which he has impressed like no other: Electrical gas discharges. Goldstein describes in this book his discovery of canal rays, which has given important impulses for modern atomic physics. For his research Goldstein received the Prix Hebert of the Parisienne Academie des sciences, the Hughes medal, and was repeatedly proposed for the Nobel prize. In Germany for the Jewish scientist the acknowledgement remained far-reachingly refused until after the war.

  5. Root and Canal Morphology of Mandibular Third Molars in an Iranian Population

    OpenAIRE

    Maryam Kuzekanani; Jahangir Haghani; Hossein Nosrati

    2012-01-01

    Background and aims A through knowledge of the root canal morphology is required for successful endodontic ther-apy. The aim of this study was to investigate the root and canal morphology of mandibular third molars in Kerman, a prov-ince in southeast of Iran. Materials and methods One-hundred-fifty extracted mandibular third molars were collected randomly from different dental clinics in Kerman. The root canal anatomy and morphology of each tooth was carefully studied using a clearing tech-ni...

  6. Maxillary lateral incisors with two canals and two separate curved roots

    Directory of Open Access Journals (Sweden)

    Ajit George Mohan

    2012-01-01

    Full Text Available Variation in the roots and root canal anatomy seems to be the norm rather than an exception. For a successful endodontic treatment, a clinician should have a thorough knowledge of the internal and external dental anatomy and its variations. Maxillary lateral incisors usually exhibit single canal with a single root. In this case, clinical examination and radiographs clearly demonstrates the presence of two root canals with two separate curved roots. This case report emphasizes the need for attention during endodontic management of maxillary lateral incisors.

  7. Novel navigation technique for the endodontic treatment of a molar with pulp canal calcification and apical pathology.

    Science.gov (United States)

    Shi, Xilin; Zhao, Shiyong; Wang, Weidong; Jiang, Qianzhou; Yang, Xuechao

    2018-04-01

    Apical periodontitis, the inflammation of periapical tissue, commonly requires root canal treatment to achieve apical healing. However, if it is accompanied by pulp canal calcification, the treatment becomes complicated, and locating the root canal can be challenging. This case report describes a novel approach for treating a molar with pulp canal calcification and apical pathology. Due to the risk of perforation during treatment, a digitally printed template was used to assist in accurately locating the root canal. After six months, the patient was asymptomatic and the periradicular radiolucency was gradually reducing in size. © 2017 Australian Society of Endodontology Inc.

  8. Anal canal duplication and triplication: a rare entity with different presentations.

    Science.gov (United States)

    Palazon, P; Julia, V; Saura, L; de Haro, I; Bejarano, M; Rovira, C; Tarrado, X

    2017-05-01

    Anal canal duplication (ACD) is the rarest of gastrointestinal duplications. Few cases have been reported. Most cases present as an opening in the midline, posterior to the normal anus. The aim of our revision is to contribute with eight new cases, some of them with unusual presentations: five presented as the typical form, one with a perianal nodule, and two presented as two separate orifices (anal canal triplication). Complete excision was performed in all patients with no complications. ACD is the most distal and the least frequent digestive duplication. Its treatment should be surgical excision, to avoid complications such as abscess, fistulization, or malignization. Anal canal triplication has never been described before.

  9. Risk-Based Disposal Plan for PCB Paint in the TRA Fluorinel Dissolution Process Mockup and Gamma Facilities Canal

    Energy Technology Data Exchange (ETDEWEB)

    R. A. Montgomery

    2008-05-01

    This Toxic Substances Control Act Risk-Based Polychlorinated Biphenyl Disposal plan was developed for the Test Reactor Area Fluorinel Dissolution Process Mockup and Gamma Facilities Waste System, located in Building TRA-641 at the Reactor Technology Complex, Idaho National Laboratory Site, to address painted surfaces in the empty canal under 40 CFR 761.62(c) for paint, and under 40 CFR 761.61(c) for PCBs that may have penetrated into the concrete. The canal walls and floor will be painted with two coats of contrasting non-PCB paint and labeled as PCB. The canal is covered with open decking; the access grate is locked shut and signed to indicate PCB contamination in the canal. Access to the canal will require facility manager permission. Protective equipment for personnel and equipment entering the canal will be required. Waste from the canal, generated during ultimate Decontamination and Decommissioning, shall be managed and disposed as PCB Bulk Product Waste.

  10. ProTaper rotary instrument fracture during root canal preparation: a comparison between rotary and hybrid techniques.

    Science.gov (United States)

    Farid, Huma; Khan, Farhan Raza; Rahman, Munawar

    2013-03-01

    This study aimed to compare the frequency of ProTaper rotary instrument fracture with rotary (conventional) and hybrid (rotary and hand files) canal preparation techniques. Secondary objectives were to determine whether there was an association of ProTaper file fracture with the canal curvature and to compare the mean time required for canal preparation in the two techniques. An in vitro experiment was conducted on 216 buccal canals of extracted maxillary and mandibular first molars. After creating an access cavity and a glide path for each canal, a periapical radiograph was taken and the canal curvature was measured with Schneider's technique. The canals were then randomly divided into Group A (rotary technique) and Group B (hybrid technique). The length of ProTaper files were measured before and after each canal preparation. Time taken for each canal preparation was recorded. A total of seven ProTaper files fractured in Group A (P=0.014) in canals with a curvature >25 degrees (PProTaper rotary files, although time consuming, was safer in canals having a curvature greater than 25 degrees.

  11. Evaluation of Root Canal Preparation Using Rotary System and Hand Instruments Assessed by Micro-Computed Tomography.

    Science.gov (United States)

    Stavileci, Miranda; Hoxha, Veton; Görduysus, Ömer; Tatar, Ilkan; Laperre, Kjell; Hostens, Jeroen; Küçükkaya, Selen; Muhaxheri, Edmond

    2015-06-20

    Complete mechanical preparation of the root canal system is rarely achieved. Therefore, the purpose of this study was to evaluate and compare the root canal shaping efficacy of ProTaper rotary files and standard stainless steel K-files using micro-computed tomography. Sixty extracted upper second premolars were selected and divided into 2 groups of 30 teeth each. Before preparation, all samples were scanned by micro-computed tomography. Thirty teeth were prepared with the ProTaper system and the other 30 with stainless steel files. After preparation, the untouched surface and root canal straightening were evaluated with micro-computed tomography. The percentage of untouched root canal surface was calculated in the coronal, middle, and apical parts of the canal. We also calculated straightening of the canal after root canal preparation. Results from the 2 groups were statistically compared using the Minitab statistical package. ProTaper rotary files left less untouched root canal surface compared with manual preparation in coronal, middle, and apical sector (p<0.001). Similarly, there was a statistically significant difference in root canal straightening after preparation between the techniques (p<0.001). Neither manual nor rotary techniques completely prepared the root canal, and both techniques caused slight straightening of the root canal.

  12. Cleaning and shaping curved root canals: Mtwo® vs ProTaper® instruments, a lab comparison

    Directory of Open Access Journals (Sweden)

    Kuzekanani Maryam

    2009-01-01

    Full Text Available Objectives: The purpose of this study was to compare root canal preparation in curved canals in molar teeth with the rotary NiTi Mtwo and ProTaper systems in terms of canal shape and smear layer. Materials and Methods: Mesiobuccal canals of 60 molar teeth with angles of curvature between 25 and 35 degrees were prepared with a torque controlled low speed engine; 30 canals for each system. Each individual instrument was used to prepare four root canals and the time required for preparation was recorded. Standardized radiographs were taken before and following instrumentation and used to determine changes in canal curvature. Results: There was no significant difference in preparation time between the two systems. No instruments separated during use. The Mtwo system gave a statistically smaller change in canal curvature and thus was better for maintaining the original shape of the root canal, with less transportation (P less than 0.05. The greatest difference was seen for maxillary molar teeth. When prepared root canals were examined by SEM there was no difference between the two systems at the coronal, middle or apical thirds. Conclusion: Overall, the results of this study suggest that Mtwo instruments are preferable for situations where canals are curved, particularly for maxillary molars.

  13. Closure of the vertebral canal in human embryos and fetuses.

    Science.gov (United States)

    Mekonen, Hayelom K; Hikspoors, Jill P J M; Mommen, Greet; Kruepunga, Nutmethee; Köhler, S Eleonore; Lamers, Wouter H

    2017-08-01

    The vertebral column is the paradigm of the metameric architecture of the vertebrate body. Because the number of somites is a convenient parameter to stage early human embryos, we explored whether the closure of the vertebral canal could be used similarly for staging embryos between 7 and 10 weeks of development. Human embryos (5-10 weeks of development) were visualized using Amira 3D ® reconstruction and Cinema 4D ® remodelling software. Vertebral bodies were identifiable as loose mesenchymal structures between the dense mesenchymal intervertebral discs up to 6 weeks and then differentiated into cartilaginous structures in the 7th week. In this week, the dense mesenchymal neural processes also differentiated into cartilaginous structures. Transverse processes became identifiable at 6 weeks. The growth rate of all vertebral bodies was exponential and similar between 6 and 10 weeks, whereas the intervertebral discs hardly increased in size between 6 and 8 weeks and then followed vertebral growth between 8 and 10 weeks. The neural processes extended dorsolaterally (6th week), dorsally (7th week) and finally dorsomedially (8th and 9th weeks) to fuse at the midthoracic level at 9 weeks. From there, fusion extended cranially and caudally in the 10th week. Closure of the foramen magnum required the development of the supraoccipital bone as a craniomedial extension of the exoccipitals (neural processes of occipital vertebra 4), whereas a growth burst of sacral vertebra 1 delayed closure until 15 weeks. Both the cranial- and caudal-most vertebral bodies fused to form the basioccipital (occipital vertebrae 1-4) and sacrum (sacral vertebrae 1-5). In the sacrum, fusion of its so-called alar processes preceded that of the bodies by at least 6 weeks. In conclusion, the highly ordered and substantial changes in shape of the vertebral bodies leading to the formation of the vertebral canal make the development of the spine an excellent, continuous staging system for

  14. Variations in the Root Form and Root Canal Morphology of Permanent Mandibular First Molars in a Sri Lankan Population

    Directory of Open Access Journals (Sweden)

    Roshan Peiris

    2015-01-01

    Full Text Available The present study was conducted to determine the number of roots and morphology of the root canal system of permanent mandibular first molars (M1 in a Sri Lankan population. Sample of 529 M1 teeth was used. The number of roots was examined and the lengths of the mesial and distal roots were measured to the nearest 0.01 mm. Vacuum injection protocol was used to inject China ink into the root canal system, making it transparent. Root canal morphology was recorded using Vertucci’s classification. Presence of furcation canals, position of lateral canals, intercanal communications, level of bifurcation, and convergence of the root canal system were recorded. M1 showed three roots in 4.1% of the sample. Commonest root canal morphology of the mesial root was type IV and the distal root was type I. The level of bifurcation of the root canals was commonly observed in the cervical one-third of the root while convergence was observed in the apical one-third in both roots. Prevalence of three rooted mandibular first molars is less than 5%. Mesial root showed the most variable canal morphology. Prevalence of furcation canals was 1.5% while that of middle mesial canals was 0.2%.

  15. C-shaped root canal configuration in mandibular second premolar: Report of an unusual case and its endodontic management

    Directory of Open Access Journals (Sweden)

    Dipali Y Shah

    2012-01-01

    Full Text Available The C-shaped root canal system is an aberration of the root canal system in which a characteristic fin or web connects individual canals, resulting in a C-shaped cross section. This configuration has been rarely reported in the mandibular second premolar. The only other known reported case of a C-shaped canal, with its configuration, in relation to mandibular second premolar is of an extracted tooth. The purpose of this report is to describe the diagnosis, configuration and endodontic management of C-shaped root canal in mandibular second premolar. Clinical techniques to addresses the challenges in endodontic disinfection as well as cleaning and shaping of the C-shaped canal, which is prone to endodontic mishaps, are also discussed in this case report. Reporting of this case emphasizes the need and added advantage of using the dental operating microscope hand in hand with conventional radiography in management of the C-shaped root canal configuration.

  16. Evaluation of the anterior and posterior ethmoidal canal by computed tomography

    International Nuclear Information System (INIS)

    Cankal, F.; Apaydin, N.; Acar, H.I.; Elhan, A.; Tekdemir, I.; Yurdakul, M.; Kaya, M.; Esmer, A.F.

    2004-01-01

    AIM: To examine the anatomy, length and angulation of the anterior and posterior ethmoidal canals (AECs and PECs) using computed tomography (CT), and to determine the anatomical landmarks in which the canals are expected to be seen in transverse and coronal planes. MATERIALS AND METHODS: CT images of 150 patients were analysed. One, 2, and 3 mm thick sections were obtained separately in axial and coronal images. The frequency of visualization of the AECs and PECs, and if present, a third canal, was noted. The course and the angulation of the AEC and the PEC in transverse and coronal planes were recorded. On axial sections the distance between the AEC and PEC and the previously defined landmarks were measured. On coronal images, the distances were calculated from the thickness of the cross-section and the number of sections between the various structures. RESULTS: The AEC was identified as a separate canal in 84% of patients, and was embedded in the ethmoid roof in 16%. The PEC was seen as a separate canal in 8% and was present in the ethmoid roof in 92%. On the 1 mm thick coronal and transverse sections, a third canal was identified at the junction of the middle and posterior third of the AEC-PEC distance in both of the images. The average lengths of these canals were 4-12 mm (mean 8.2 mm) for the AEC, and 2-13 mm (mean 7.6 mm) for the PEC. CONCLUSIONS: To avoid the complications that can develop during endoscopic sinus surgery; the course, length and the angulations of the anterior and posterior ethmoidal arteries and their canals can be identified by CT in standard positions if a sufficiently thin section thickness is used. The present study has shown the exact CT localization of the AECs and PECS, which are frequently overlooked when evaluating para-nasal sinuses

  17. Fibrous Dysplasia of the Temporal Bone with External Auditory Canal Stenosis and Secondary Cholesteatoma.

    Science.gov (United States)

    Liu, Yu-Hsi; Chang, Kuo-Ping

    2016-04-01

    Fibrous dysplasia is a slowly progressive benign fibro-osseous disease, rarely occurring in temporal bones. In these cases, most bony lesions developed from the bony part of the external auditory canals, causing otalgia, hearing impairment, otorrhea, and ear hygiene blockade and probably leading to secondary cholesteatoma. We presented the medical history of a 24-year-old woman with temporal monostotic fibrous dysplasia with secondary cholesteatoma. The initial presentation was unilateral conductive hearing loss. A hard external canal tumor contributing to canal stenosis and a near-absent tympanic membrane were found. Canaloplasty and type I tympanoplasty were performed, but the symptoms recurred after 5 years. She received canal wall down tympanomastoidectomy with ossciculoplasty at the second time, and secondary cholesteatoma in the middle ear was diagnosed. Fifteen years later, left otorrhea recurred again and transcanal endoscopic surgery was performed for middle ear clearance. Currently, revision surgeries provide a stable auditory condition, but her monostotic temporal fibrous dysplasia is still in place.

  18. Red River Waterway, Lock and Dam 3: Report 3 - Sedimentation Conditions Hydraulic Model Investigation

    National Research Council Canada - National Science Library

    McCollum, Randy

    1997-01-01

    ...) To study tendency for scour and fill in the approaches to the lock and dam and determine training structures that would improve navigation conditions and minimize dredging requirements and scour problems.

  19. Carcinoma of the middle ear and external auditory canal

    International Nuclear Information System (INIS)

    Hahn, S.S.; Kim, J.A.; Goodchild, N.; Constable, W.C.

    1983-01-01

    Thirty-one patients with malignant tumors of the middle ear and external auditory canal (EAC) were observed at the University of Virginia Hospital from 1956 through 1980. Of 27 patients with carcinoma, 21 had squamous cell carcinoma, 4 had basal cell carcinoma and 2 had adenoid cystic carcinoma. The 27 patients with carcinoma are reviewed with regard to clinical presentation, treatment modality, results and complications. The majority (67%) of patients had a history of chronic ear drainage, 22% had a previous mastoidectomy or polypectomy and 7% had an associated cholesteatoma. Eighty percent of patients with carcinoma limited to EAC were alive and well at 5 years, compared to 43% of patients with involvement of the middle ear. Fifty-six percent of patients without invasion of the petrous bone were alive at 5 years compared to only 20% of patients with petrous bone involvement. The data strongly suggest that survival depends on the extent of disease. The corrected disease free 5 year survival rates were 14% for patients who had surgery alone and 50% for those who had surgery and radiotherapy. Of the three patients with advanced disease who received radiotherapy alone, none survived five years

  20. Otolith and Vertical Canal Contributions to Dynamic Postural Control

    Science.gov (United States)

    Black, F. Owen

    1999-01-01

    The objective of this project is to determine: 1) how do normal subjects adjust postural movements in response to changing or altered otolith input, for example, due to aging? and 2) how do patients adapt postural control after altered unilateral or bilateral vestibular sensory inputs such as ablative inner ear surgery or ototoxicity, respectively? The following hypotheses are under investigation: 1) selective alteration of otolith input or abnormalities of otolith receptor function will result in distinctive spatial, frequency, and temporal patterns of head movements and body postural sway dynamics. 2) subjects with reduced, altered, or absent vertical semicircular canal receptor sensitivity but normal otolith receptor function or vice versa, should show predictable alterations of body and head movement strategies essential for the control of postural sway and movement. The effect of altered postural movement control upon compensation and/or adaptation will be determined. These experiments provide data for the development of computational models of postural control in normals, vestibular deficient subjects and normal humans exposed to unusual force environments, including orbital space flight.

  1. Endodontic management of mandibular second premolar with three roots and three root canals: A case report

    Directory of Open Access Journals (Sweden)

    Nidhi Shrivastava

    2014-01-01

    Full Text Available High level of success in endodontic treatment requires an understanding of root canal anatomy and morphology. The clinician must be prepared to identify those teeth that tend to vary generally from norm. Thorough debridement and obturation of such teeth can be challenging and failing to do so can lead to treatment failure. Mandibular premolars have earned the reputation for having aberrant anatomy. However, the occurrence of three separate canals with three separate foramina in mandibular premolars is very rare. The incidence of three canals is as high as 23% in mandibular first premolars, whereas in second premolars incidence is as low as 0.4%. Three rooted mandibular second premolar is reported to be 0.2%. This case report describes endodontic management of one such tooth with unusual morphological variations in canal anatomy of mandibular second premolar.

  2. Computed tomography evaluation of rotary systems on the root canal transportation and centering ability

    Energy Technology Data Exchange (ETDEWEB)

    Pagliosa, Andre; Raucci-Neto, Walter; Silva-Souza, Yara Teresinha Correa; Alfredo, Edson, E-mail: ysousa@unaerp.br [Universidade de Ribeirao Preto (UNAERP), SP (Brazil). Fac. de Odontologia; Sousa-Neto, Manoel Damiao; Versiani, Marco Aurelio [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Fac. de Odoentologia

    2015-03-01

    The endodontic preparation of curved and narrow root canals is challenging, with a tendency for the prepared canal to deviate away from its natural axis. The aim of this study was to evaluate, by cone-beam computed tomography, the transportation and centering ability of curved mesiobuccal canals in maxillary molars after biomechanical preparation with different nickel-titanium (NiTi) rotary systems. Forty teeth with angles of curvature ranging from 20° to 40° and radii between 5.0 mm and 10.0 mm were selected and assigned into four groups (n = 10), according to the biomechanical preparative system used: Hero 642 (HR), Liberator (LB), ProTaper (PT), and Twisted File (TF). The specimens were inserted into an acrylic device and scanned with computed tomography prior to, and following, instrumentation at 3, 6 and 9 mm from the root apex. The canal degree of transportation and centering ability were calculated and analyzed using one-way ANOVA and Tukey’s tests (α = 0.05). The results demonstrated no significant difference (p > 0.05) in shaping ability among the rotary systems. The mean canal transportation was: -0.049 ± 0.083 mm (HR); -0.004 ± 0.044 mm (LB); -0.003 ± 0.064 mm (PT); -0.021 ± 0.064 mm (TF). The mean canal centering ability was: -0.093 ± 0.147 mm (HR); -0.001 ± 0.100 mm (LB); -0.002 ± 0.134 mm (PT); -0.033 ± 0.133 mm (TF). Also, there was no significant difference among the root segments (p > 0.05). It was concluded that the Hero 642, Liberator, ProTaper, and Twisted File rotary systems could be safely used in curved canal instrumentation, resulting in satisfactory preservation of the original canal shape. (author)

  3. Computed tomography evaluation of rotary systems on the root canal transportation and centering ability

    Directory of Open Access Journals (Sweden)

    André PAGLIOSA

    2015-01-01

    Full Text Available Abstract : The endodontic preparation of curved and narrow root canals is challenging, with a tendency for the prepared canal to deviate away from its natural axis. The aim of this study was to evaluate, by cone-beam computed tomography, the transportation and centering ability of curved mesiobuccal canals in maxillary molars after biomechanical preparation with different nickel-titanium (NiTi rotary systems. Forty teeth with angles of curvature ranging from 20° to 40° and radii between 5.0 mm and 10.0 mm were selected and assigned into four groups (n = 10, according to the biomechanical preparative system used: Hero 642 (HR, Liberator (LB, ProTaper (PT, and Twisted File (TF. The specimens were inserted into an acrylic device and scanned with computed tomography prior to, and following, instrumentation at 3, 6 and 9 mm from the root apex. The canal degree of transportation and centering ability were calculated and analyzed using one-way ANOVA and Tukey’s tests (α = 0.05. The results demonstrated no significant difference (p > 0.05 in shaping ability among the rotary systems. The mean canal transportation was: -0.049 ± 0.083 mm (HR; -0.004 ± 0.044 mm (LB; -0.003 ± 0.064 mm (PT; -0.021 ± 0.064 mm (TF. The mean canal centering ability was: -0.093 ± 0.147 mm (HR; -0.001 ± 0.100 mm (LB; -0.002 ± 0.134 mm (PT; -0.033 ± 0.133 mm (TF. Also, there was no significant difference among the root segments (p > 0.05. It was concluded that the Hero 642, Liberator, ProTaper, and Twisted File rotary systems could be safely used in curved canal instrumentation, resulting in satisfactory preservation of the original canal shape.

  4. Computed tomography evaluation of rotary systems on the root canal transportation and centering ability

    International Nuclear Information System (INIS)

    Pagliosa, Andre; Raucci-Neto, Walter; Silva-Souza, Yara Teresinha Correa; Alfredo, Edson; Sousa-Neto, Manoel Damiao; Versiani, Marco Aurelio

    2015-01-01

    The endodontic preparation of curved and narrow root canals is challenging, with a tendency for the prepared canal to deviate away from its natural axis. The aim of this study was to evaluate, by cone-beam computed tomography, the transportation and centering ability of curved mesiobuccal canals in maxillary molars after biomechanical preparation with different nickel-titanium (NiTi) rotary systems. Forty teeth with angles of curvature ranging from 20° to 40° and radii between 5.0 mm and 10.0 mm were selected and assigned into four groups (n = 10), according to the biomechanical preparative system used: Hero 642 (HR), Liberator (LB), ProTaper (PT), and Twisted File (TF). The specimens were inserted into an acrylic device and scanned with computed tomography prior to, and following, instrumentation at 3, 6 and 9 mm from the root apex. The canal degree of transportation and centering ability were calculated and analyzed using one-way ANOVA and Tukey’s tests (α = 0.05). The results demonstrated no significant difference (p > 0.05) in shaping ability among the rotary systems. The mean canal transportation was: -0.049 ± 0.083 mm (HR); -0.004 ± 0.044 mm (LB); -0.003 ± 0.064 mm (PT); -0.021 ± 0.064 mm (TF). The mean canal centering ability was: -0.093 ± 0.147 mm (HR); -0.001 ± 0.100 mm (LB); -0.002 ± 0.134 mm (PT); -0.033 ± 0.133 mm (TF). Also, there was no significant difference among the root segments (p > 0.05). It was concluded that the Hero 642, Liberator, ProTaper, and Twisted File rotary systems could be safely used in curved canal instrumentation, resulting in satisfactory preservation of the original canal shape. (author)

  5. U.S. Navigated Waterway Mile Marker Locations from USCOE source data, Geographic NAD83, LOSCO (2000) [river_mile_markers_USACE_1994

    Data.gov (United States)

    Louisiana Geographic Information Center — This is a point dataset representing 10,044 sequential mile positions of navigable inland waterways and the Gulf Intracoastal Waterway. These data were developed as...

  6. The Effects of NiTi Hand and Rotary Canal Master U and K-Flex Instrumentation of Root Canal Morphology

    Science.gov (United States)

    1992-09-01

    Rotary Canal Master "U" and K-Flex Instrumentation of Root Canal Morphology 6. AUTHOR(S) Robert H. Haller 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES... endodontic failure. B. STATET OF THE PREL]2U Conventional endodontic instruments have re.nained basically unchanged since the introduction of the K-type...F;hcw"e that this nO𔃾 instruneent destim tended ti- produce rounder pr rMticns with • t!-rnnVortaticn than c rnvrnticnal 4 endodontic instruments

  7. Living Shorelines: Assessing Geomorphic Change and Water Quality in an Urban Waterway

    Science.gov (United States)

    Huggins, A.; Schwartz, M. C.; Schmutz, P. P.

    2017-12-01

    In recent years, alternative strategies for shoreline armoring have become increasingly popular with coastal property owners. In Northwest Florida, local agencies implemented plans to attenuate wave action and reduce landward shore recession in an urban bayou by installing living shorelines. Living shorelines are constructed in the inter-tidal zones and incorporate both hard and soft structured stabilization. Generally, the hard component is fossilized oyster shells and the soft component is planted intertidal vegetation, such as Spartina alterniflora (Smooth cordgrass) and Juncus roemererianus (Black needlerush). Living shorelines were intended to comprise both ecological and societal implications by significantly slowing erosion processes for property owners, by utilizing oyster beds to improve water quality, and by fostering new ecological habitats in the marsh grasses. The issue presented with living shoreline management is long-term studies have not been carried out on these engineered systems. For this study, geospatial technology was utilized to create 3D images of terrain by interpolation of data points using a TotalStation to compute geomorphic change. Additionally, water samples were analyzed using traditional wet chemistry laboratory methods to determine total oxidized nitrogen (TON), ammonium, and orthophosphate content in water. Over a short three-month preliminary study, sediment accretion was observed primarily within the vegetation with the bulk of the erosion occurring around the oyster beds. TON was detected at levels between 10 µM and 30 µM, ammonium up to 5 µM, and orthophosphate was only detected in very low levels, consistently quality data will be used to establish baseline data for future research to determine volumetric geomorphic change,and to set a standard for water quality trends, surrounding oyster beds and vegetation in response to climatic events.

  8. Red River Waterway, Louisiana, Texas, Arkansas, and Oklahoma, Mississippi River to Shreveport, Louisiana. General Reevaluation Report.

    Science.gov (United States)

    1982-12-01

    occur, includes salt cedar, false nettle , cocklebur, goldenrod, dog fennel, and Bermuda grass. The more mature riverine habitat usually consists of a mix...broomsedge, various legumes, and many other species might occur in this habitat type. Pastureland is a food source for many insect species and, if not grazed...too heavily, provides abundant habitat to insects as well as succulent growth for herbivorous mammals. Songbirds most common to the pasture are

  9. Biodegradability of dissolved organic carbon in permafrost soils and waterways: a meta-analysis

    Science.gov (United States)

    Vonk, J. E.; Tank, S. E.; Mann, P. J.; Spencer, R. G. M.; Treat, C. C.; Striegl, R. G.; Abbott, B. W.; Wickland, K. P.

    2015-06-01

    As Arctic regions warm, the large organic carbon pool stored in permafrost becomes increasingly vulnerable to thaw and decomposition. The transfer of newly mobilized carbon to the atmosphere and its potential influence upon climate change will largely depend on the reactivity and subsequent fate of carbon delivered to aquatic ecosystems. Dissolved organic carbon (DOC) is a key regulator of aquatic metabolism and its biodegradability will determine the extent and rate of carbon release from aquatic ecosystems to the atmosphere. Knowledge of the mechanistic controls on DOC biodegradability is however currently poor due to a scarcity of long-term data sets, limited spatial coverage of available data, and methodological diversity. Here, we performed parallel biodegradable DOC (BDOC) experiments at six Arctic sites (16 experiments) using a standardized incubation protocol to examine the effect of methodological differences used as common practice in the literature. We further synthesized results from 14 aquatic and soil leachate BDOC studies from across the circum-arctic permafrost region to examine pan-Arctic trends in BDOC. An increasing extent of permafrost across the landscape resulted in higher BDOC losses in both soil and aquatic systems. We hypothesize that the unique composition of permafrost-derived DOC combined with limited prior microbial processing due to low soil temperature and relatively shorter flow path lengths and transport times, resulted in higher overall terrestrial and freshwater BDOC loss. Additionally, we found that the fraction of BDOC decreased moving down the fluvial network in continuous permafrost regions, i.e. from streams to large rivers, suggesting that highly biodegradable DOC is lost in headwater streams. We also observed a seasonal (January-December) decrease in BDOC losses in large streams and rivers, but no apparent change in smaller streams and soil leachates. We attribute this seasonal change to a combination of factors including

  10. A Fisheries Evaluation of the Richland and Wapato Canal Fish Screening Facilities, Spring 1987 : Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Neitzel, Duane A.; Abernethy, C.Scott; Lusty, E.William; Wampler, Sally J.

    1988-02-01

    We evaluated the effectiveness of new fish screening facilities at the Richland and Wapato canals in south-central Washington State. The screen integrity tests at the Richland Screens indicated that 100% of fall chinook salmon fry (Oncorhynchus tshawytscha) released in front of the screens were prevented from entering the canal behind the screens. Our estimate is based on a 61% catch efficiency for control fish planted behind the screens. At the Wapato Canal, we estimated that between 3% and 4% of the test fish were either impinged on the screen surface and passed over the screens or passed through faulty screen seals. Our estimate is based over the screens or passed through faulty screen seals. Our estimate is based on a greater than 90% capture of control fish released in front of the screens. At the Wapato Screens, we estimated that 0.8% of steelhead smolts (Salmo gairdneri) and 1.4% of spring chinook salmon smolts released during low canal flow tests wee descaled. During full canal flow tests, 1.6% of the steelhead and 3.1% of the spring chinook salmon released were descaled. The fish return pipe at the Wapato Canal was tested: the estimate of descaled test fish wa not different from the estimate of descaled control fish. The time required for fish to exit from the Wapato Screen forebay varied with species and with canal flow. During low canal flows, 43.2% of steelhead and 61.6% of spring chinook salmon smolts released at the trash racks were captured in the fish return within 96 hr. 11 refs., 11 figs., 10 tabs.

  11. The road less taken: modularization and waterways as a domestic disaster response mechanism.

    Science.gov (United States)

    Donahue, Donald A; Cunnion, Stephen O; Godwin, Evelyn A

    2013-01-01

    Preparedness scenarios project the need for significant healthcare surge capacity. Current planning draws heavily from the military model, leveraging deployable infrastructure to augment or replace extant capabilities. This approach would likely prove inadequate in a catastrophic disaster, as the military model relies on forewarning and an extended deployment cycle. Local equipping for surge capacity is prohibitively costly while movement of equipment can be subject to a single point of failure. Translational application of maritime logistical techniques and an ancient mode of transportation can provide a robust and customizable approach to disaster relief for greater than 90 percent of the American population.

  12. Environmental security of the coastal seafloor in the sea ports and waterways of the Mediterranean region

    Energy Technology Data Exchange (ETDEWEB)

    Obhodas, Jasmina, E-mail: jobhodas@irb.h [Institute Ruder Boskovic, Bijenicka c.54, 10000 Zagreb (Croatia); Valkovic, Vladivoj [A.C.T.d.o.o., Prilesje 4, 10000 Zagreb (Croatia); Sudac, Davorin [Institute Ruder Boskovic, Bijenicka c.54, 10000 Zagreb (Croatia); Matika, Dario [Institute for Researches and Development of Defense Systems, Ilica 256b, 10000 Zagreb (Croatia); Pavic, Ivica [Ministry of Defense, Croatian Navy, Dubrovacka 49, 21000 Split (Croatia); Kollar, Robert [A.C.T.d.o.o., Prilesje 4, 10000 Zagreb (Croatia)

    2010-07-21

    The Mediterranean coastal seafloor is littered with man-made objects and materials, including a variety of ammunition in many areas. In addition, sediments in ports, harbors and marinas are contaminated with elevated concentrations of chemicals used as biocides in antifouling paints. In order to reach a satisfactory level of environmental security of the coastal sea areas, fast neutron activation analysis with detection of associated alpha particles and energy dispersive X-ray fluorescence, both in laboratory and inside an autonomous underwater vehicle for in-situ measurements, has been used for the characterization of the objects on the seafloor. Measurements have shown that gamma ray spectra are able to distinguish threat material from the surrounding material. Analysis of more than 700 coastal sea sediment samples has resulted in concentration distribution maps indicating the locations of 'hot spots', which might interfere with threat material identification.

  13. Modelling cholera epidemics: the role of waterways, human mobility and sanitation

    OpenAIRE

    Mari, L.; Bertuzzo, E.; Righetto, L.; Casagrandi, R.; Gatto, M.; Rodriguez-Iturbe, I.; Rinaldo, A.

    2011-01-01

    We investigate the role of human mobility as a driver for long-range spreading of cholera infections, which primarily propagate through hydrologically controlled ecological corridors. Our aim is to build a spatially explicit model of a disease epidemic, which is relevant to both social and scientific issues. We present a two-layer network model that accounts for the interplay between epidemiological dynamics, hydrological transport and long-distance dissemination of the pathogen Vibrio choler...

  14. Modelling cholera epidemics: the role of waterways, human mobility and sanitation.

    Science.gov (United States)

    Mari, L; Bertuzzo, E; Righetto, L; Casagrandi, R; Gatto, M; Rodriguez-Iturbe, I; Rinaldo, A

    2012-02-07

    We investigate the role of human mobility as a driver for long-range spreading of cholera infections, which primarily propagate through hydrologically controlled ecological corridors. Our aim is to build a spatially explicit model of a disease epidemic, which is relevant to both social and scientific issues. We present a two-layer network model that accounts for the interplay between epidemiological dynamics, hydrological transport and long-distance dissemination of the pathogen Vibrio cholerae owing to host movement, described here by means of a gravity-model approach. We test our model against epidemiological data recorded during the extensive cholera outbreak occurred in the KwaZulu-Natal province of South Africa during 2000-2001. We show that long-range human movement is fundamental in quantifying otherwise unexplained inter-catchment transport of V. cholerae, thus playing a key role in the formation of regional patterns of cholera epidemics. We also show quantitatively how heterogeneously distributed drinking water supplies and sanitation conditions may affect large-scale cholera transmission, and analyse the effects of different sanitation policies.

  15. Remote Sensing Monitoring Methods for Detecting Invasive Weed Coverage in Delta Waterways and Bay Marshlands

    Science.gov (United States)

    Potter, Christopher

    2018-01-01

    This presentation is part of the Independent Science Board of the State of California Delta Stewardship Council brown bag seminar series on the "How the Delta is Monitored", followed with a panel discussion. Various remote sensing approaches for aquatic vegetation will be reviewed. Key research and application issues with remote sensing monitoring in the Delta will be addressed.

  16. Modelling cholera epidemics: the role of waterways, human mobility and sanitation

    Science.gov (United States)

    Mari, L.; Bertuzzo, E.; Righetto, L.; Casagrandi, R.; Gatto, M.; Rodriguez-Iturbe, I.; Rinaldo, A.

    2012-01-01

    We investigate the role of human mobility as a driver for long-range spreading of cholera infections, which primarily propagate through hydrologically controlled ecological corridors. Our aim is to build a spatially explicit model of a disease epidemic, which is relevant to both social and scientific issues. We present a two-layer network model that accounts for the interplay between epidemiological dynamics, hydrological transport and long-distance dissemination of the pathogen Vibrio cholerae owing to host movement, described here by means of a gravity-model approach. We test our model against epidemiological data recorded during the extensive cholera outbreak occurred in the KwaZulu-Natal province of South Africa during 2000–2001. We show that long-range human movement is fundamental in quantifying otherwise unexplained inter-catchment transport of V. cholerae, thus playing a key role in the formation of regional patterns of cholera epidemics. We also show quantitatively how heterogeneously distributed drinking water supplies and sanitation conditions may affect large-scale cholera transmission, and analyse the effects of different sanitation policies. PMID:21752809

  17. Waterborne Commerce of the United States, Calendar Year 1982. Part 1. Waterways and Harbors, Atlantic Coast.

    Science.gov (United States)

    1984-07-01

    191, FIESl FISH, EXCEPT SHELLFIS ...... 2a2I PLATIC .aTE.’ILS . . . I . . . 24 DISILT FU L 1-... I,131:.......... 341l 1 &8QICATED HEY lL...4,2..... 2639 BASIC CHEMICALS AND PROD. NEC ............... 3,2,26 230,027 47,344 111R.............25,097.0 2a2 PLATIC NATBILS

  18. Effects of self-adjusting file, Mtwo, and ProTaper on the root canal wall.

    Science.gov (United States)

    Hin, Ellemieke S; Wu, Min-Kai; Wesselink, Paul R; Shemesh, Hagay

    2013-02-01

    The purpose of this ex vivo study was to observe the incidence of cracks in root dentin after root canal preparation with hand files, self-adjusting file (SAF), ProTaper, and Mtwo. One hundred extracted mandibular premolars with single canals were randomly selected. Two angulated radiographs were taken for each tooth, and the width of the canal was measured at 9 mm from the apex. Five groups of 20 teeth each were comparable in canal width. The control group was left unprepared. Four experimental groups were instrumented with hand files, ProTaper, Mtwo, and SAF. Roots were then sectioned horizontally and observed under a microscope. The presence of dentinal cracks and their location were noted. The difference between the experimental groups was analyzed with a χ(2) test. No cracks were observed in the control group. In the experimental groups, ProTaper, Mtwo, and SAF caused cracks in 35%, 25%, and 10% of teeth, respectively. The hand-file group did not show any dentinal cracks (P ProTaper and Mtwo caused more cracks than hand files (P .05). Instrumentation of root canals with SAF, Mtwo, and ProTaper could cause damage to root canal dentin. SAF has a tendency to cause less dentinal cracks as compared with ProTaper or Mtwo. Copyright © 2013 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  19. LPS levels in root canals after the use of ozone gas and high frequency electrical pulses

    Directory of Open Access Journals (Sweden)

    Tiago André Fontoura de MELO

    2016-01-01

    Full Text Available Abstract The present study aims to verify the effect of ozone gas (OZY® System and high frequency electric pulse (Endox® System systems on human root canals previously contaminated with Escherichia colilipopolysaccharide (LPS. Fifty single-rooted teeth had their dental crowns removed and root lengths standardized to 16 mm. The root canals were prepared up to #60 hand K-files and sterilized using gamma radiation with cobalt 60. The specimens were divided into the following five groups (n = 10 based on the disinfection protocol used: OZY® System, one 120-second-pulse (OZY 1p; OZY® System, four 24-second-pulses (OZY 4p; and Endox® System (ENDOX. Contaminated and non-contaminated canals were exposed only to apyrogenic water and used as positive (C+ and negative (C- controls, respectively. LPS (O55:B55 was administered in all root canals except those belonging to group C-. After performing disinfection, LPS samples were collected from the canals using apyrogenic paper tips. Limulus Amoebocyte Lysate (LAL was used to quantify the LPS levels, and the data obtained was analyzed using one-way ANOVA. The disinfection protocols used were unable to reduce the LPS levels significantly (p = 0.019. The use of ozone gas and high frequency electric pulses was not effective in eliminating LPS from the root canals.

  20. In vitro comparative study of manual and mechanical rotary instrumentation of root canals using computed tomography.

    Science.gov (United States)

    Limongi, Orlando; de Albuquerque, Diana Santana; Baratto Filho, Flares; Vanni, José Roberto; de Oliveira, Elias P Motcy; Barletta, Fernando Branco

    2007-01-01

    This in vitro study compared, using computed tomography (CT), the amount of dentin removed from root canal walls by manual and mechanical rotary instrumentation techniques. Forty mandibular incisors with dental crown and a single canal were selected. The teeth were randomly assigned to two groups, according to the technique used for root canal preparation: Group I - manual instrumentation with stainless steel files; Group II - mechanical instrumentation with RaCe rotary nickel-titanium instruments. In each tooth, root dentin thickness of the buccal, lingual, mesial and distal surfaces in the apical, middle and cervical thirds of the canal was measured (in mm) using a multislice CT scanner (Siemens Emotion, Duo). Data were stored in the SPSS v. 11.5 and SigmaPlot 2001 v. 7.101 softwares. After crown opening, working length was determined, root canals were instrumented and new CT scans were taken for assessment of root dentin thickness. Pre- and post-instrumentation data were compared and analyzed statistically by ANOVA and Tukey's post-hoc test for significant differences (p=0.05). Based on the findings of this study, it may be concluded that regarding dentin removal from root canal walls during instrumentation, neither of the techniques can be considered more effective than the other.

  1. Medium and long term perspectives of Inland Waterway Transport in the European Union. Executive Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-01-15

    If inland shipping is to remain the greenest mode of transport, it will need to improve its environmental act in the coming years. If it fails to do so, it will be overtaken by road transport. That is one of the conclusions of the title study. In this study CE Delft performed the analyses of emissions and offers recommendations for reducing them. The key issue in this regard is to create financial incentives for ship owners to invest in modern, clean engines and retrofit technologies, complementing standards for new engines. The study will be used as a basis for drawing up policy on inland shipping towards 2020, in line with the EU White Paper on transport policy.

  2. 78 FR 26799 - Waterway Suitability Assessment for Expansion of Liquefied Gas Terminals; Beaumont, TX

    Science.gov (United States)

    2013-05-08

    ... Partnership LP has submitted a Letter of Intent and a Waterway Suitability Assessment to the Coast Guard.... Martin Operating Partnership's Stanolind Cut Terminal in Beaumont, Texas submitted an LOI on January 25... the physical nature of the affected waterway and issues of safety and security associated with LNG or...

  3. Blue Ear Cyst: A Rare Eccrine Hidrocystoma of the Ear Canal and Successful Endoscopic Excision

    Directory of Open Access Journals (Sweden)

    Taha A. Mur

    2016-01-01

    Full Text Available Aims. Hidrocystomas are benign cystic growths of the apocrine and eccrine sweat glands. These cystic lesions have been well documented on the face, head, and neck, but rarely in the external auditory canal. Presentation of Case. A 67-year-old woman presented with a bluish cystic mass partially occluding the external auditory canal and interfering with hearing aid use. Lesion was excised completely via a transcanal endoscopic approach with excellent cosmetic results, no canal stenosis, and no recurrence at 1-year follow-up. Discussion. We present a rare eccrine hidrocystoma of the external auditory canal and successful excision of this benign lesion. We describe the surgical management using a transcanal endoscopic approach and follow-up results. An eccrine gland cyst that presents as a mass occluding the external auditory canal is quite rare. There are only a few such cases reported in the literature. These masses can be mistaken for basal cell carcinomas or cholesterol granulomas but can be easily differentiated using histopathology. Conclusion. Eccrine hidrocystoma is a cystic lesion of sweat glands, rarely found in the external auditory canal. A characteristic bluish hue aids in diagnosis and surgical excision using ear endoscopy provides excellent control.

  4. The Coast Guard Proceedings of the Marine Safety and Security Council. Waterways. Summer 2016

    Science.gov (United States)

    2016-01-01

    Number of Establishments Employment 2012 Revenues ($1,000) Aquaculture 3,093 5,798 1,371,707 Finsh farming and sh hatcheries #N/A #N/A #N/A Shell sh...farming #N/A #N/A #N/A Other aquaculture #N/A #N/A #N/A Fishing 2,259 5,990 5,118,939 Finsh shing 1,288 3,669 #N/A Shell sh shing 925 2,200 #N/A...described above, whereas renewable diesel is produced via hydrotreating or biomass -to-liquid conversion pro- cesses, the results being a fuel that is

  5. National Waterway Network (line), Geographic WGS84, BTS (2006) [usace_nav_waterway_lin_BTS_2006

    Data.gov (United States)

    Louisiana Geographic Information Center — The National Waterway Network is a comprehensive network database of the nation's navigable waterways. The data set covers the 48 contiguous states plus the District...

  6. National Waterway Network (node), Geographic WGS84, BTS (2006) [usace_nav_waterway_nod_BTS_2006

    Data.gov (United States)

    Louisiana Geographic Information Center — The National Waterway Network is a comprehensive network database of the nation's navigable waterways. The data set covers the 48 contiguous states plus the District...

  7. [Association between Bacteroides forsythus in the infected root canals and clinical symptoms of chronic apical periodontitis].

    Science.gov (United States)

    Huang, Ding-ming; Fu, Chun-hua; Zhou, Xue-dong

    2005-01-01

    To investigate the distribution of Bacteroides forsythus in root canals with chronic apical periodontitis and to determine its associations with clinical symptoms. Thirty-eight tooth root canals from 31 subjects were studied with a 16S rDNA-directed polymerase chain reaction (PCR). These teeth were classified into symptomatic and asymptomatic groups according to the clinical symptoms and signs, including spontaneous pain, percussion pain, sinus tract and swelling, respectively. Ten of the 38 root canal samples were positive for B. forsythus. The prevalence of B. forsythus was 26.3% for 38 root canals, 45.5% for spontaneous pain group, 39.1% for percussion pain group, 29.4% for sinus tract group, 42.9% for swelling group, respectively. Significant positive associations were observed between B. forsythus in infected root canals and the spontaneous pain, percussion pain, and swelling of apical periodontitis, respectively (OR=infinity, 9, 12; Papical periodontitis (OR=1.33). B. forsythus colonized in the infected root canals. It is the putative pathogen of apical periodontitis.

  8. The Inauguration of Suez Canal and Its Impacts on Navigation in seas

    Directory of Open Access Journals (Sweden)

    maryam sheypari

    2016-03-01

    Full Text Available The inauguration of Suez Canal, which connects the Mediterranean Sea to Red Sea, had a great impact on marine communications. In other words, this canal not only offered the easier access of European countries to their colonies in Asia because of the new marine route between Asia and Europe but also developed the use of steamboats instead of sailboats due to its specific geographical position. In fact, the trade between Asia and Europe spanned via the seas located between Asia and Europe after four centuries as the result of inauguration of Suez Canal in 1869A.D. Furthermore, the importance of Seas i.e. Mediterranean Sea, Red Sea and black Sea had the great economic _ political role in the world and the expansion of rivalry between countries in Persian Gulf due to this canal.  This study investigates to the process of diving Suez and the influence of Suez Canal on marine changes among the countries, especially in Persian Gulf by the beginning of the First World War. The outcome of this study demonstrates that the inauguration of Suez Canal led to the rivalry situation for England in the period of its supremacy.

  9. Nonsurgical root canal therapy of large cyst-like inflammatory periapical lesions and inflammatory apical cysts.

    Science.gov (United States)

    Lin, Louis M; Ricucci, Domenico; Lin, Jarshen; Rosenberg, Paul A

    2009-05-01

    It is a general belief that large cyst-like periapical lesions and apical true cysts caused by root canal infection are less likely to heal after nonsurgical root canal therapy. Nevertheless, there is no direct evidence to support this assumption. A large cyst-like periapical lesion or an apical true cyst is formed within an area of apical periodontitis and cannot form by itself. Therefore, both large cyst-like periapical lesions and apical true cysts are of inflammatory and not of neoplastic origin. Apical periodontitis lesions, regardless of whether they are granulomas, abscesses, or cysts, fail to heal after nonsurgical root canal therapy for the same reason, intraradicular and/or extraradicular infection. If the microbial etiology of large cyst-like periapical lesions and inflammatory apical true cysts in the root canal is removed by nonsurgical root canal therapy, the lesions might regress by the mechanism of apoptosis in a manner similar to the resolution of inflammatory apical pocket cysts. To achieve satisfactory periapical wound healing, surgical removal of an apical true cyst must include elimination of root canal infection.

  10. Quantifying canal leakage rates using a mass-balance approach and heat-based hydraulic conductivity estimates in selected irrigation canals, western Nebraska, 2007 through 2009

    Science.gov (United States)

    Hobza, Christopher M.; Andersen, Michael J.

    2010-01-01

    The water supply in areas of the North Platte River Basin in the Nebraska Panhandle has been designated as fully appropriated or overappropriated by the Nebraska Department of Natural Resources (NDNR). Enacted legislation (Legislative Bill 962) requires the North Platte Natural Resources District (NPNRD) and the NDNR to develop an Integrated Management Plan (IMP) to balance groundwater and surface-water supply and demand in the NPNRD. A clear understanding of the groundwater and surface-water systems is critical for the development of a successful IMP. The primary source of groundwater recharge in parts of the NPNRD is from irrigation canal leakage. Because canal leakage constitutes a large part of the hydrologic budget, spatially distributing canal leakage to the groundwater system is important to any management strategy. Surface geophysical data collected along selected reaches of irrigation canals has allowed for the spatial distribution of leakage on a relative basis; however, the actual magnitude of leakage remains poorly defined. To address this need, the U.S. Geological Survey, in cooperation with the NPNRD, established streamflow-gaging stations at upstream and downstream ends from two selected canal reaches to allow a mass-balance approach to be used to calculate daily leakage rates. Water-level and sediment temperature data were collected and simulated at three temperature monitoring sites to allow the use of heat as a tracer to estimate the hydraulic conductivity of canal bed sediment. Canal-leakage rates were estimated by applying Darcy's Law to modeled vertical hydraulic conductivity and either the estimated or measured hydraulic gradient. This approach will improve the understanding of the spatial and temporal variability of canal leakage in varying geologic settings identified in capacitively coupled resistivity surveys. The high-leakage potential study reach of the Tri-State Canal had two streamflow-gaging stations and two temperature monitoring

  11. Adductor Canal Block versus Femoral Nerve Block and Quadriceps Strength

    DEFF Research Database (Denmark)

    Jæger, Pia Therese; Nielsen, Zbigniew Jerzy Koscielniak; Henningsen, Lene Marianne

    2013-01-01

    : The authors hypothesized that the adductor canal block (ACB), a predominant sensory blockade, reduces quadriceps strength compared with placebo (primary endpoint, area under the curve, 0.5-6 h), but less than the femoral nerve block (FNB; secondary endpoint). Other secondary endpoints were...

  12. Conditions of using floating cranes for lifting sunken objects on inland waterways

    OpenAIRE

    Slobodan M. Radojević

    2012-01-01

    This paper presents the conditions for using floating cranes for lifting sunken vessels and other objects on inland waterways. Basic technical data are given together with technical details for the usage of floa ting cranes for lifting sunken objects. The paper points to the importance of lifting sunken objects and their removal from inland waterways in the Republic of Serbia.

  13. Conditions of using floating cranes for lifting sunken objects on inland waterways

    Directory of Open Access Journals (Sweden)

    Slobodan M. Radojević

    2012-04-01

    Full Text Available This paper presents the conditions for using floating cranes for lifting sunken vessels and other objects on inland waterways. Basic technical data are given together with technical details for the usage of floa ting cranes for lifting sunken objects. The paper points to the importance of lifting sunken objects and their removal from inland waterways in the Republic of Serbia.

  14. 78 FR 59339 - Intracoastal Waterway Route “Magenta Line” on NOAA Nautical Charts

    Science.gov (United States)

    2013-09-26

    ... waterways have been based principally on surveys made from 60 to 80 years ago and, necessarily, are obsolete... found where the charted Intracoastal Waterway Route (``magenta line'') passes on the wrong side of aids... specifically seeks comments regarding: 1. How do you currently access the magenta line? On paper nautical...

  15. Evaluation of Root Canal Preparation Using Rotary System and Hand Instruments Assessed by Micro-Computed Tomography

    Science.gov (United States)

    Stavileci, Miranda; Hoxha, Veton; Görduysus, Ömer; Tatar, Ilkan; Laperre, Kjell; Hostens, Jeroen; Küçükkaya, Selen; Muhaxheri, Edmond

    2015-01-01

    Background Complete mechanical preparation of the root canal system is rarely achieved. Therefore, the purpose of this study was to evaluate and compare the root canal shaping efficacy of ProTaper rotary files and standard stainless steel K-files using micro-computed tomography. Material/Methods Sixty extracted upper second premolars were selected and divided into 2 groups of 30 teeth each. Before preparation, all samples were scanned by micro-computed tomography. Thirty teeth were prepared with the ProTaper system and the other 30 with stainless steel files. After preparation, the untouched surface and root canal straightening were evaluated with micro-computed tomography. The percentage of untouched root canal surface was calculated in the coronal, middle, and apical parts of the canal. We also calculated straightening of the canal after root canal preparation. Results from the 2 groups were statistically compared using the Minitab statistical package. Results ProTaper rotary files left less untouched root canal surface compared with manual preparation in coronal, middle, and apical sector (protary techniques completely prepared the root canal, and both techniques caused slight straightening of the root canal. PMID:26092929

  16. MULTIPLE SPINAL CANAL MENINGIOMAS

    Directory of Open Access Journals (Sweden)

    Nandigama Pratap Kumar

    2016-10-01

    Full Text Available BACKGROUND Meningiomas of the spinal canal are common tumours with the incidence of 25 percent of all spinal cord tumours. But multiple spinal canal meningiomas are rare in compare to solitary lesions and account for 2 to 3.5% of all spinal meningiomas. Most of the reported cases are both intra cranial and spinal. Exclusive involvement of the spinal canal by multiple meningiomas are very rare. We could find only sixteen cases in the literature to the best of our knowledge. Exclusive multiple spinal canal meningiomas occurring in the first two decades of life are seldom reported in the literature. We are presenting a case of multiple spinal canal meningiomas in a young patient of 17 years, who was earlier operated for single lesion. We analysed the literature, with illustration of our case. MATERIALS AND METHODS In September 2016, we performed a literature search for multiple spinal canal meningiomas involving exclusively the spinal canal with no limitation for language and publication date. The search was conducted through http://pubmed.com, a wellknown worldwide internet medical address. To the best of our knowledge, we could find only sixteen cases of multiple meningiomas exclusively confined to the spinal canal. Exclusive multiple spinal canal meningiomas occurring in the first two decades of life are seldom reported in the literature. We are presenting a case of multiple spinal canal meningiomas in a young patient of 17 years, who was earlier operated for solitary intradural extra medullary spinal canal meningioma at D4-D6 level, again presented with spastic quadriparesis of two years duration and MRI whole spine demonstrated multiple intradural extra medullary lesions, which were excised completely and the histopathological diagnosis was transitional meningioma. RESULTS Patient recovered from his weakness and sensory symptoms gradually and bladder and bowel symptoms improved gradually over a period of two to three weeks. CONCLUSION Multiple

  17. In Vitro Comparative Study of the Working Length Determination with Radiovisiography and Conventional Radiography in Dilacerated Canals

    Directory of Open Access Journals (Sweden)

    Ali Bagherpour

    2015-06-01

    Full Text Available Introduction: The aim of this study was to compare digital and conventional radiography in determining the working length of dilacerated canals.Methods: Thirty nine human extracted single-rooted teeth with root curvature more than 35 degrees were included in this study. After access preparation, a file was inserted into the canal and advanced until the file tip was visualized at the foramen. With measurement of the file length using a millimeter ruler, true canal length was determined for each canal. Then, teeth were mounted in acrylic blocks and canal length was estimated by using on-screen digital radiography with both 3- and 6-clicks measurement and from conventional radiography by conforming a preserved file on the image of the root canal.Results: There were no significant differences in measurement accuracy between the true canal length and conventional radiographic length, but there were significant difference between both digital radiographic techniques with true canal length. There was no significant correlation between root curvature and canal length estimation error of studied methods.Conclusion: In dilacerated canals, the accuracy of determination of working length by using conventional radiography is higher than digital radiography

  18. The 'Amstel Canal' in Amsterdam Canal construction as part of the medieval reclamation and drainage system of the Western Netherlands wilderness

    Science.gov (United States)

    Abrahamse, Jaap-Evert; Kosian, Menne; Weerts, Henk

    2013-04-01

    Usually, Amsterdam is presented as a river city, with the river Amstel as the trade route towards its hinterland, the IJ sea-branch as the portal to the world and its Dam as a focal point of transshipment and trade. Geomorphological, sedimentological, historical and historical-geographical evidence however, points towards the straight part of the Amstel, now located in Amsterdam, as a drainage canal that was dug in the aftermath of the 'Great Reclamation' of the 11th and 12th centuries. During this period, large parts of the wilderness in Utrecht and Holland were cultivated and put to agricultural use. Prior to the 'Great Reclamations', large oligotrophic (Sphagnum) peat bogs drained by small rivers were characteristic of the entire region. All along the straight Amstel canal, Sphagnum peat is found, which is indicative of the area's former peat bog conditions. The 'Amstel Canal' connected two natural meandering watercourses, one at the north and one at the south of the canal. The soil along both watercourses exists of eutrophic peat, which is indicative of repeated natural flooding. This is a strong indication of the anthropogenous origin of the straight part of the Amstel. The reason for digging the Amstel canal was not to create better trade links; it was a local component of a solution for major regional drainage problems in the provinces of Utrecht and Holland. These problems arose from the silting up of the Rhine rivermouth around 1100AD. Because of this, the precipitation surplus of the entire region could not be drained to the North Sea by this route anymore. This led to increased flooding and subsequently to conflicts between the rulers of Holland and Utrecht. In 1165AD, these conflicts reached a point where the Holy Roman Emperor intervened. The ruling of Barbarossa eventually led to a compromise: Utrecht and Holland redirected the entire drainage system of the region from the North Sea to the Zuiderzee in a concerted effort. This operation consisted of

  19. The anatomical perspective of human occipital condyle in relation to the hypoglossal canal, condylar canal, and jugular foramen and its surgical significance

    Directory of Open Access Journals (Sweden)

    Ranjana Verma

    2016-01-01

    Conclusion: The OC and related structures such as HC, CC, and JF are likely to have variations in respect to morphometry and morphology. This study may prove helpful to neurosurgeons operating in this field, especially during TCA where neurovascular structures emerging from these canals and foramen are more vulnerable to injury.

  20. Hearing loss and enlarged internal auditory canal in children.

    Science.gov (United States)

    Santos, Saturnino; Domínguez, M Jesús; Cervera, Javier; Suárez, Alicia; Bueno, Antonio; Bartolomé, Margarita; López, Rafael

    2014-01-01

    Among the temporal bone abnormalities that can be found in the etiological study of paediatric sensorineural hearing loss (SNHL) by imaging techniques, those related to the internal auditory canal (IAC) are the least frequent. The most prevalent of these abnormalities that is associated with SNHL is stenotic IAC due to its association with cochlear nerve deficiencies. Less frequent and less concomitant with SNHL is the finding of an enlarged IAC (>8mm). Retrospective and descriptive review of clinical associations, imaging, audiological patterns and treatment of 9 children with hearing loss and enlarged IAC in the period 1999 to 2012. Two groups of patients are described. The first, without association with vestibulocochlear dysplasias, consisted of: 2 patients with SNHL without other temporal bone or systemic abnormalities, one with bilateral mixed HL from chromosome 18q deletion, one with a genetic X-linked DFN3 hearing loss, one with unilateral hearing loss in neurofibromatosis type 2 with bilateral acoustic neuroma, and one with unilateral hearing loss with cochlear nerve deficiency. The second group, with association with vestibulocochlear dysplasias, was comprised of: one patient with moderate bilateral mixed hearing loss in branchio-oto-renal syndrome, one with profound unilateral SNHL with recurrent meningitis, and another with profound bilateral SNHL with congenital hypothyroidism. The presence of an enlarged IAC in children can be found in different clinical and audiological settings with relevancies that can range from life-threatening situations, such as recurrent meningitis, to isolated hearing loss with no other associations. Copyright © 2013 Elsevier España, S.L. All rights reserved.

  1. Modal-split effects of climate change: The effects of low water levels on the competitive position of inland waterway transport in the River Rhine area

    NARCIS (Netherlands)

    Jonkeren, O.E.; Jourquin, B.; Rietveld, P.

    2011-01-01

    Future climate change is expected to affect inland waterway transport in most main natural waterways in Europe. For the river Rhine it is expected that, in summer, more and longer periods with low water levels will occur. In periods of low water levels inland waterway vessels have to reduce their

  2. Pre-operative assessment of impacted mandibular third molar and inferior alveolar canal using orthopantomograhpy and cone beam computed tomography

    Directory of Open Access Journals (Sweden)

    Mahmuda Akter

    2016-12-01

    Full Text Available The aim of this study was to assess the proximity and relation of impacted mandibular third molar and inferior alveolar canal on orthopantomogram and cone beam computed tomography (CBCT. Sixty impacted mandibular third molars having close proximity with the  inferior alveolar canal were included. CBCT images were done to determine the exact location and relationship of impacted third molar tooth and inferior alveolar canal. We assessed the radiographic signs from orthopantomogram, the course of  inferior alveolar canal and proximity to the third molar tooth in CBCT. The buccal course of  inferior alveolar canal was most frequently detected (n=36 in CBCT findings. The impacted lower third molar roots were 55% contact with the  inferior alveolar canal and 45% separate from the canal. On orthopantomogram, the following signs were strongly correlated with actual contact: Superimposed relationship between the third molar and the inferior alveolar canal. CBCT is useful as a presurgical planning in patients with impacted mandibular third molar showing close proximity to the  inferior alveolar canal.

  3. Study of the inferior alveolar canal and mental foramen on digital panoramic images.

    Science.gov (United States)

    Pria, Carlos M; Masood, Farah; Beckerley, Joy M; Carson, Robert E

    2011-07-01

    To study the radiographic location of the mental foramen and appearance of the inferior alveolar canal and the relationship between image gray values and the clarity of inferior alveolar canal on the digital panoramic images and to evaluate if the histogram equalization of the digital image would improve the visualization of the inferior alveolar canal outline on the digital panoramic images in the mandible. Five hundred digital panoramic images were evaluated by two examiners using a specific inclusion criteria. Only the right side of the mandible was studied. Chi-square analyses were used for comparisons of distributions. Mean and median pixel values were analyzed separately with a one-way analysis of variance. Also, percentages were calculated to report the usefulness of the histogram equalization for visualization of canal. RESULTS show variation in location of mental foramen. Most frequent location of the mental foramen was reported as first and second premolar region. Chi-square analysis showed that the frequency of occurrence of the mental foramen was equally probable for any of the three locations. The study did not find significant usefulness of the gray values obtained from the histogram equalization in predicting the clarity of inferior alveolar canal outlines. Knowing the normal relationship and the anatomical variation of the maxillofacial structures for each patient is important for surgical implant treatment planning to avoid future complications. It is also important to be familiar with the advantages and limitations of diagnostic aids available before making treatment planning decisions based on such findings. Digital imaging, Panoramic, Inferior alveolar canal, Mental foramen. How to cite this article: Pria CM, Masood F, Beckerley JM, Carson RE. Study of the Inferior Alveolar Canal and Mental Foramen on Digital Panoramic Images. J Contemp Dent Pract 2011;12(4):265-271. Source of support: Nil Conflict of interest: None declared.

  4. Entrainment, retention, and transport of freely swimming fish in junction gaps between commercial barges operating on the Illinois Waterway

    Science.gov (United States)

    Davis, Jeremiah J.; Jackson, P. Ryan; Engel, Frank; LeRoy, Jessica Z.; Neeley, Rebecca N.; Finney, Samuel T.; Murphy, Elizabeth A.

    2016-01-01

    Large Electric Dispersal Barriers were constructed in the Chicago Sanitary and Ship Canal (CSSC) to prevent the transfer of invasive fish species between the Mississippi River Basin and the Great Lakes Basin while simultaneously allowing the passage of commercial barge traffic. We investigated the potential for entrainment, retention, and transport of freely swimming fish within large gaps (> 50 m3) created at junction points between barges. Modified mark and capture trials were employed to assess fish entrainment, retention, and transport by barge tows. A multi-beam sonar system enabled estimation of fish abundance within barge junction gaps. Barges were also instrumented with acoustic Doppler velocity meters to map the velocity distribution in the water surrounding the barge and in the gap formed at the junction of two barges. Results indicate that the water inside the gap can move upstream with a barge tow at speeds near the barge tow travel speed. Water within 1 m to the side of the barge junction gaps was observed to move upstream with the barge tow. Observed transverse and vertical water velocities suggest pathways by which fish may potentially be entrained into barge junction gaps. Results of mark and capture trials provide direct evidence that small fish can become entrained by barges, retained within junction gaps, and transported over distances of at least 15.5 km. Fish entrained within the barge junction gap were retained in that space as the barge tow transited through locks and the Electric Dispersal Barriers, which would be expected to impede fish movement upstream.

  5. Design of canals

    CERN Document Server

    Swamee, P K

    2015-01-01

    The book presents firsthand material from the authors on design of hydraulic canals. The book discusses elements of design based on principles of hydraulic flow through canals. It covers optimization of design based on usage requirements and economic constraints. The book includes explicit design equations and design procedures along with design examples for varied cases. With its comprehensive coverage of the principles of hydraulic canal design, this book will prove useful to students, researchers, and practicing engineers. End-of-chapter pedagogical elements make it ideal for use in graduate courses on hydraulic structures offered by most civil engineering departments across the world.

  6. Radiography of the mandible prior to endosseous implant treatment. Localization of the mandibular canal and assessment of trabecular bone

    International Nuclear Information System (INIS)

    Lindh, C.

    1996-03-01

    Mandibular autopsy specimens were examined with different radiographic techniques in order to evaluate the visibility of the mandibular canal and the measurement accuracy of distances related to the mandibular canal. Hypocycloidal, spiral and computed tomography (CT) were superior to periapical and panoramic radiography in visualizing the mandibular canal. The tomographic techniques were more accurate when measurements of distances related to the mandibular canal were performed. No difference in measurement accuracy was found between the tomographic techniques. Concerning visibility of the mandibular canal, interobserver agreement was lowest for periapical radiography and highest for CT. Intraobserver agreement was moderate or good for all techniques. A high interobserver variation was found for measurability of distances related to the mandibular canal. The trabecular bone tissue in mandibular autopsy specimens was studied concerning different characteristics. A classification system to be used prior to implant treatment, based on the trabecular pattern in periapical radiographs, was proposed. 74 refs

  7. Radiography of the mandible prior to endosseous implant treatment. Localization of the mandibular canal and assessment of trabecular bone

    Energy Technology Data Exchange (ETDEWEB)

    Lindh, C.

    1996-03-01

    Mandibular autopsy specimens were examined with different radiographic techniques in order to evaluate the visibility of the mandibular canal and the measurement accuracy of distances related to the mandibular canal. Hypocycloidal, spiral and computed tomography (CT) were superior to periapical and panoramic radiography in visualizing the mandibular canal. The tomographic techniques were more accurate when measurements of distances related to the mandibular canal were performed. No difference in measurement accuracy was found between the tomographic techniques. Concerning visibility of the mandibular canal, interobserver agreement was lowest for periapical radiography and highest for CT. Intraobserver agreement was moderate or good for all techniques. A high interobserver variation was found for measurability of distances related to the mandibular canal. The trabecular bone tissue in mandibular autopsy specimens was studied concerning different characteristics. A classification system to be used prior to implant treatment, based on the trabecular pattern in periapical radiographs, was proposed. 74 refs.

  8. Cytotoxicity of 5% Tamarindus indica extract and 3% hydrogen peroxide as root canal irrigation

    Directory of Open Access Journals (Sweden)

    Erawati Wulandari

    2008-09-01

    Full Text Available Background: Preparation of root canal is an important stage in endodontic treatment. During conducting preparation, it is always be followed with root canal irrigation that has aim to clean root canal from necrotic tissue remains, grind down dentin powder, micro organism, wet the root canal to make preparation process of root canal easier, and solute root canal content at area that can not be reached by equipment. Flesh of Tamarindus indica (pulpa tamarindorum is used as traditional medicine and it contains vitamin C (antioxidant, protein, fat, glucose, etc. Previous research shows that 5% tamarindus indica extract can clean smear layer but it is more cytotoxicity to cell line BHK–21 than sterilized aquabides. Purpose: This research is to compare cytotoxicity between 5% Tamarindus indica extract with 3% H2O2 as root canal irrigation material. Method: Four teen culture cell line BHK 21 divides into 2 groups. Group 1 is treated with 3% H2O2 and Group 2 is treated with 5% Tamarindus indica extract, for about 2.5 minutes in every group. Then, living and death cell percentage is measured. Data is analyzed with independent t test with significant level of 0.05%. Result: The research showed that death cell in group 1 was 29.3% and in group 2 was 21.1%. There was a significant different (p < 0.05 between group 1 and group 2. Conclusion: Cytotoxicity of 5% Tamarindus indica extract to the cell line BHK–21 is lower than 3% H2O2.

  9. Curved canals: Ancestral files revisited

    Directory of Open Access Journals (Sweden)

    Jain Nidhi

    2008-01-01

    Full Text Available The aim of this article is to provide an insight into different techniques of cleaning and shaping of curved root canals with hand instruments. Although a plethora of root canal instruments like ProFile, ProTaper, LightSpeed ® etc dominate the current scenario, the inexpensive conventional root canal hand files such as K-files and flexible files can be used to get optimum results when handled meticulously. Special emphasis has been put on the modifications in biomechanical canal preparation in a variety of curved canal cases. This article compiles a series of clinical cases of root canals with curvatures in the middle and apical third and with S-shaped curvatures that were successfully completed by employing only conventional root canal hand instruments.

  10. Marine habitat mapping of the Milford Haven Waterway, Wales, UK: Comparison of facies mapping and EUNIS classification for monitoring sediment habitats in an industrialized estuary

    Science.gov (United States)

    Carey, Drew A.; Hayn, Melanie; Germano, Joseph D.; Little, David I.; Bullimore, Blaise

    2015-06-01

    A detailed map and dataset of sedimentary habitats of the Milford Haven Waterway (MHW) was compiled for the Milford Haven Waterway Environmental Surveillance Group (MHWESG) from seafloor images collected in May, 2012 using sediment-profile and plan-view imaging (SPI/PV) survey techniques. This is the most comprehensive synoptic assessment of sediment distribution and benthic habitat composition available for the MHW, with 559 stations covering over 40 km2 of subtidal habitats. In the context of the MHW, an interpretative framework was developed that classified each station within a 'facies' that included information on the location within the waterway and inferred sedimentary and biological processes. The facies approach provides critical information on landscape-scale habitats including relative location and inferred sediment transport processes and can be used to direct future monitoring activities within the MHW and to predict areas of greatest potential risk from contaminant transport. Intertidal sediment 'facies' maps have been compiled in the past for MHW; this approach was expanded to map the subtidal portions of the waterway. Because sediment facies can be projected over larger areas than individual samples (due to assumptions based on physiography, or landforms) they represent an observational model of the distribution of sediments in an estuary. This model can be tested over time and space through comparison with additional past or future sample results. This approach provides a means to evaluate stability or change in the physical and biological conditions of the estuarine system. Initial comparison with past results for intertidal facies mapping and grain size analysis from grab samples showed remarkable stability over time for the MHW. The results of the SPI/PV mapping effort were cross-walked to the European Nature Information System (EUNIS) classification to provide a comparison of locally derived habitat mapping with European-standard habitat

  11. In situ biomonitoring of juvenile Chinook salmon (Onchorhynchus tshawytscha) using biomarkers of chemical exposures and effects in a partially remediated urbanized waterway of the Puget Sound, WA

    Energy Technology Data Exchange (ETDEWEB)

    Browne, Eva [Department of Environmental and Occupational Health Sciences, University of Washington, 4225 Roosevelt Way Northeast, Suite 100, Seattle, WA 98105-6099 (United States); Kelley, Matthew; Zhou, Guo-Dong; He, Ling Yu; McDonald, Thomas; Wang, Shirley [Department of Environmental and Occupational Health, Texas A and M Health Science Center, College Station, TX 77843-1266 (United States); Duncan, Bruce [US Environmental Protection Agency, Region 10, 1200 Sixth Avenue, Seattle, WA 98101 (United States); Meador, James [Ecotoxicology Division, National Marine Fisheries Service, Seattle, WA 98105 (United States); Donnelly, Kirby [Department of Environmental and Occupational Health, Texas A and M Health Science Center, College Station, TX 77843-1266 (United States); Gallagher, Evan, E-mail: evang3@u.washington.edu [Department of Environmental and Occupational Health Sciences, University of Washington, 4225 Roosevelt Way Northeast, Suite 100, Seattle, WA 98105-6099 (United States)

    2010-10-15

    In situ biomonitoring has been used to assess the effects of pollution on aquatic species in heavily polluted waterways. In the current study, we used in situ biomonitoring in conjunction with molecular biomarker analysis to determine the effects of pollutant exposure in salmon caged in the Duwamish waterway, a Pacific Northwest Superfund site that has been subject to remediation. The Duwamish waterway is an important migratory route for Pacific salmon and has received historic inputs of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs). Juvenile pre-smolt Chinook salmon (Oncorhynchus tshawytscha) caged for 8 days in the three contaminated sites in close proximity within the Duwamish were analyzed for steady state hepatic mRNA expression of 7 exposure biomarker genes encompassing several gene families and known to be responsive to pollutants, including cytochrome P4501A (CYP1A) and CYP2K1, glutathione S-transferase {pi} class (GST-{pi}), microsomal GST (mGST), glutamylcysteine ligase catalytic subunit (GCLC), UDP-glucuronyltransferase family 1 (UDPGT), and type 2 deiodinase (type 2 DI, or D2). Quantitation of gene expression was accomplished by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) in assays developed specifically for Chinook salmon genes. Gill PAH-DNA adducts were assessed as a chemical effects biomarker using {sup 32}P-postlabeling. The biomarkers in the field-caged fish were analyzed with respect to caged animals maintained at the hatchery receiving flow-through water. Chemical analysis of sediment samples from three field sampling sites revealed relatively high concentrations of total PAHs in one site (site B2, 6711 ng/g dry weight) and somewhat lower concentrations of PAHs in two adjacent sites (sites B3 and B4, 1482 and 1987 ng/g, respectively). In contrast, waterborne PAHs at all of the sampling sites were relatively low (<1 ng/L). Sediment PCBs at the sites ranged from a low of 421 ng/g at site B3

  12. Panoramic radiographs underestimate extensions of the anterior loop and mandibular incisive canal

    Energy Technology Data Exchange (ETDEWEB)

    De Brito, Ana Caroline Ramos; Nejaim, Yuri; De Freitas, Deborah Queiroz [Dept. of Oral Diagnosis, Division of Oral Radiology, Piracicaba Dental School, University of Campinas, Sao Paulo (Brazil); De Oliveira Santos, Christiano [Dept. of Stomatology, Public Oral Health and Forensic Dentistry, School of Dentistry of Ribeirao Preto, University of Sao Paulo, Sao Paulo (Brazil)

    2016-09-15

    The purpose of this study was to detect the anterior loop of the mental nerve and the mandibular incisive canal in panoramic radiographs (PAN) and cone-beam computed tomography (CBCT) images, as well as to determine the anterior/mesial extension of these structures in panoramic and cross-sectional reconstructions using PAN and CBCT images. Images (both PAN and CBCT) from 90 patients were evaluated by 2 independent observers. Detection of the anterior loop and the incisive canal were compared between PAN and CBCT. The anterior/mesial extension of these structures was compared between PAN and both cross-sectional and panoramic CBCT reconstructions. In CBCT, the anterior loop and the incisive canal were observed in 7.7% and 24.4% of the hemimandibles, respectively. In PAN, the anterior loop and the incisive canal were detected in 15% and 5.5% of cases, respectively. PAN presented more difficulties in the visualization of structures. The anterior/mesial extensions ranged from 0.0 mm to 19.0 mm on CBCT. PAN underestimated the measurements by approximately 2.0 mm. CBCT appears to be a more reliable imaging modality than PAN for preoperative workups of the anterior mandible. Individual variations in the anterior/mesial extensions of the anterior loop of the mental nerve and the mandibular incisive canal mean that is not prudent to rely on a general safe zone for implant placement or bone surgery in the interforaminal region.

  13. Panoramic radiographs underestimate extensions of the anterior loop and mandibular incisive canal

    International Nuclear Information System (INIS)

    De Brito, Ana Caroline Ramos; Nejaim, Yuri; De Freitas, Deborah Queiroz; De Oliveira Santos, Christiano

    2016-01-01

    The purpose of this study was to detect the anterior loop of the mental nerve and the mandibular incisive canal in panoramic radiographs (PAN) and cone-beam computed tomography (CBCT) images, as well as to determine the anterior/mesial extension of these structures in panoramic and cross-sectional reconstructions using PAN and CBCT images. Images (both PAN and CBCT) from 90 patients were evaluated by 2 independent observers. Detection of the anterior loop and the incisive canal were compared between PAN and CBCT. The anterior/mesial extension of these structures was compared between PAN and both cross-sectional and panoramic CBCT reconstructions. In CBCT, the anterior loop and the incisive canal were observed in 7.7% and 24.4% of the hemimandibles, respectively. In PAN, the anterior loop and the incisive canal were detected in 15% and 5.5% of cases, respectively. PAN presented more difficulties in the visualization of structures. The anterior/mesial extensions ranged from 0.0 mm to 19.0 mm on CBCT. PAN underestimated the measurements by approximately 2.0 mm. CBCT appears to be a more reliable imaging modality than PAN for preoperative workups of the anterior mandible. Individual variations in the anterior/mesial extensions of the anterior loop of the mental nerve and the mandibular incisive canal mean that is not prudent to rely on a general safe zone for implant placement or bone surgery in the interforaminal region

  14. 75 FR 11870 - Inland Waterways Users Board

    Science.gov (United States)

    2010-03-12

    ... DEPARTMENT OF DEFENSE Department of the Army; Corps of Engineers Inland Waterways Users Board AGENCY: Department of the Army, U.S. Army Corps of Engineers, DoD. ACTION: Notice of open meeting... is made of the forthcoming meeting. Name of Committee: Inland Waterways Users Board (Board). Date...

  15. 78 FR 44934 - Inland Waterways Users Board

    Science.gov (United States)

    2013-07-25

    ... DEPARTMENT OF DEFENSE Department of the Army; Corps of Engineers Inland Waterways Users Board AGENCY: Department of the Army, U.S. Army Corps of Engineers, DoD. ACTION: Notice of open meeting... is made of the forthcoming meeting. Name of Committee: Inland Waterways Users Board (Board). Date...

  16. 75 FR 57264 - Inland Waterways Users Board

    Science.gov (United States)

    2010-09-20

    ... DEPARTMENT OF DEFENSE Department of the Army; Corps of Engineers Inland Waterways Users Board AGENCY: Department of the Army, U.S. Army Corps of Engineers, DoD. ACTION: Notice of open meeting... is made of the forthcoming meeting. Name of Committee: Inland Waterways Users Board (Board). Date...

  17. 76 FR 11216 - Inland Waterways Users Board

    Science.gov (United States)

    2011-03-01

    ... DEPARTMENT OF DEFENSE Department of the Army; Corps of Engineers Inland Waterways Users Board AGENCY: Department of the Army, U.S. Army Corps of Engineers, DoD. ACTION: Notice of open meeting... is made of the forthcoming meeting. Name of Committee: Inland Waterways Users Board (Board). Date...

  18. 78 FR 72070 - Inland Waterways Users Board

    Science.gov (United States)

    2013-12-02

    ... DEPARTMENT OF DEFENSE Department of the Army; Corps of Engineers Inland Waterways Users Board AGENCY: Department of the Army, U.S. Army Corps of Engineers, DoD. ACTION: Notice of open meeting... is made of the forthcoming meeting. Name of Committee: Inland Waterways Users Board (Board). Date...

  19. 77 FR 69447 - Inland Waterways Users Board

    Science.gov (United States)

    2012-11-19

    ... DEPARTMENT OF DEFENSE Department of the Army; Corps of Engineers Inland Waterways Users Board AGENCY: Department of the Army, U.S. Army Corps of Engineers, DoD. ACTION: Notice of open meeting... is made of the forthcoming meeting. Name of Committee: Inland Waterways Users Board (Board). Date...

  20. ANALYSIS OF REMOTE SENSING ARCHAEOLOGY ON TRAFFIC FUNCTION TRANSFORMATION OF TONGJI GRAND CANAL IN SUI AND TANG DYNASTIES

    Institute of Scientific and Technical Information of China (English)

    WANG Xin-yuan; HE Hui; ZHOU Ying-qiu; GAO Chao; HAN Shuang-wang

    2006-01-01

    In China, most directions of river flowing are from west to east. During historic period, since the water traffic played an important role, it was very important to form a cross-horizontal net of water carriage route. Canals should be dug so as to make up the lack of north-south river. Tongji Grand Canal, dug in the first year of Daye (605 A.D.) in the Sui Dynasty, was the important component of north-south system of Grand Canals in China. It promoted economic and social development of the Sui, Tang and Song dynasties (605 A.D.-1279 A.D.). As Tongji Canal (i.e.Tongji Grand Canal) flowed across the Huaibei Plain, which is aggraded by abundant mud and sand deposit resulted from the Huanghe (Yellow) River flooding, many traces (such as old channel) and human culture heritages were buried under mud-sand. Tongji Canal was silted up, and disappeared in the Jin Dynasty (1115 A.D.-1234 A.D.). From then on, there were many different stories about the flowing route of the canal in historical literature. Based on space-bone and air-bone remote sensing imagery, we attempt to search the old channel of Tongji Canal, and supplement historical record. The paper discusses transformation process of Tongji Canal's traffic function, and resumptively summarizes the reasons of the transformation, which results from synthetic function of physical geographical, political, economic, and social conditions.

  1. Association of manual or engine-driven glide path preparation with canal centring and apical transportation: a systematic review.

    Science.gov (United States)

    Hartmann, R C; Peters, O A; de Figueiredo, J A P; Rossi-Fedele, G

    2018-04-28

    The role and effect of glide path preparation in root canal treatment remain controversial. This systematic review aims to compare apical transportation and canal centring of different glide path preparation techniques, with or without subsequent engine-driven root canal preparation. A database search in PubMed, PubMed Central, Embase, Scopus, EBSCO Dentistry & Oral Sciences Source and Virtual Health Library was conducted, using appropriate key words to identify the effect of glide path preparation (or its absence) on apical transportation and canal centring. An assessment for the risk of bias in included studies was carried out. Amongst 2146 studies, 18 satisfied the inclusion criteria. Nine studies assessed glide path preparation per se, comparing apical transportation and canal centring of rotary systems and/or manual files; eleven further investigations examined the efficacy of the glide path prior to final canal preparation with different engine-driven systems. Risk of bias and other study design features with potential influence on study outcomes and clinical implications were assessed. Based on the available evidence, and within the limitation of the studies included, preparation of a glide path using rotary sequences performs similarly (in most of the component studies) or significantly better than manual preparation when assessing apical transportation or canal centring. When compared to the absence of a glide path, canal shaping following glide path preparation was of similar, or significantly better quality, in regard to apical transportation or canal centring. © 2018 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  2. Nd:YAG Lasers Treating of Carious Lesion and Root Canal In Vitro

    Directory of Open Access Journals (Sweden)

    Danqing Xia

    2012-01-01

    Full Text Available Dental caries is a transmissible bacterial disease process, with cavities at the end, and caused by acids from bacterial metabolism. The essence of dental treatment is to clean and disinfect bacterial contamination from the tooth. In this work, we tried to demonstrate the cleaning and disinfecting effects of Nd:YAG laser irradiation on dental carious lesion and root canal in vitro. Acousto-optic Q-switched quasicontinuous and Cr3+:YAG crystal Q-switched pulse Nd:YAG lasers were employed to treat caries lesion and the root canal, respectively. Results showed that acousto-optic Q-switched quasicontinuous Nd:YAG laser irradiation and Cr3+:YAG crystal Q-switched pulse Nd:YAG laser irradiation could rapidly clean decayed material and bacterial contamination from dental carious lesion and the narrow tail end of root canal with minimally invasive in vitro, respectively. It was concluded that acousto-optic Q-switched quasicontinuous laser irradiation may be a rapid and effective alternative caries treatment, and Cr3+:YAG crystal Q-switched pulse Nd:YAG laser irradiation may be an effective method for canal cleaning and disinfecting during root canal therapy.

  3. Threats to rainfed and canal irrigated agro-ecosystems of the Punjab, Pakistan by weed infestation

    International Nuclear Information System (INIS)

    Hussain, M.; Ahmed, M.S.A.; Hameed, M.; Aqeel, M.

    2012-01-01

    To record the weed flora infesting the rainfed and canal irrigated arable fields in the Punjab province, three districts viz. Chakwal, Jhelum and Rawalpindi in rainfed agro-ecosystem, while three districts in canal irrigated wheat fields i.e., Sahiwal, Qasoor and Gujrat were surveyed comprehensively to examine weed spectra. Weeds occurring in various localities largely varied with the variation in the mode of irrigation i.e., Barani areas and Canal irrigated area. In Rainfed (Barani) areas Fumeria parviflora and Asphodelus tenuifolius were noted frequently while their representation was very rare or even absent in canal irrigated areas. Carthamus oxayacantha was also observed at some sites there. The only weeds growing infrequently were hardy grasses like Cynodon dactylon and Cyperus rotundus. None of the weed could cross the limits of occasional frequency level. Nevertheless, in canal irrigated areas Convolvulus arvensis, Anagalus arvensis, Chenopodium sp., Melilotus alba, Lepidium sativum, Lathyrus aphaca, Medicago denticulata, Rumex dentatus and Cynodon dactylon were frequently observed. Phalaris minor and Avena fatua formed very dense stands in many areas. Carthamus oxayacantha, Poa annua, Sonchus asper and Vicia sativa were recorded infrequently. The farmers of Sahiwal and Qasoor districts seem well informed about the importance and use of weedicides as a result the spectrum of weeds growing there was quite low and none of them could establish dense stands. (author)

  4. Root Canal Irrigation: Chemical Agents and Plant Extracts Against Enterococcus faecalis

    Science.gov (United States)

    Borzini, Letizia; Condò, Roberta; De Dominicis, Paolo; Casaglia, Adriano; Cerroni, Loredana

    2016-01-01

    Background: There are various microorganisms related to intra and extra-radicular infections and many of these are involved in persistent infections. Bacterial elimination from the root canal is achieved by means of the mechanical action of instruments and irrigation as well as the antibacterial effects of the irrigating solutions. Enterococcus faecalis can frequently be isolated from root canals in cases of failed root canal treatments. Antimicrobial agents have often been developed and optimized for their activity against endodontic bacteria. An ideal root canal irrigant should be biocompatible, because of its close contact with the periodontal tissues during endodontic treatment. Sodium hypoclorite (NaOCl) is one of the most widely recommended and used endodontic irrigants but it is highly toxic to periapical tissues. Objectives: To analyze the literature on the chemotherapeutic agent and plant extracts studied as root canal irrigants. In particularly, the study is focused on their effect on Enterococcus faecalis. Method: Literature search was performed electronically in PubMed (PubMed Central, MEDLINE) for articles published in English from 1982 to April 2015. The searched keywords were “endodontic irrigants” and “Enterococcus faecalis” and “essential oil” and “plant extracts”. Results: Many of the studied chemotherapeutic agents and plant extracts have shown promising results in vitro. Conclusion: Some of the considered phytotherapic substances, could be a potential alternative to NaOCl for the biomechanical treatment of the endodontic space. PMID:28217184

  5. ALIMENTARY CANAL ANATOMY AND HISTOLOGY OF THE WORKER TERMITE NEOTERMES BOSEI

    Directory of Open Access Journals (Sweden)

    LEKSONO EKOPURANTO HARIPRABOWO

    2006-01-01

    Full Text Available As social insects, termites live in a colony that consist of reproductive (drone and queen, and non-reproductive (soldiers and workers castes. Workers obtain their food directly from wood, humus, and other substances that contain cellulose. The objective of this study was to examine the alimentary canal of the Neotermes bosei workers. Observations of gut transverse section were carried out through the length, perimeter, and area of each alimentary canal region. The results showed that total length of N. bosei alimentary canal was 13.71+1.28 mm. The canal was divided into fore-, mid-, and hindgut which were 24, 28, and 48%, respectively of the gut total length. Two types of alimentary canal epithelial cells were found, i.e. the squamous and transitional cells. Areas covered with thick muscular tissues were crop, proventriculus, and rectum. Proventriculus was characterized with six large dentitions. There was no gastric caeca in N. bosei midgut, which commonly occurred in chewing insect. Secretory cells .wer e observed at proventriculus and ventriculus regions. Cardiac valve was found at the anterior end of ventriculus. Area with the largest outer perimeter was the rectum pouch. Enteric valve had three internal folds.

  6. Frequency of enterococcus faecalis in saliva and root canals with treatment failure

    International Nuclear Information System (INIS)

    Khan, I.; Shan, T.; Manzoor, M.A.

    2015-01-01

    To compare the frequency of E. faecalis in the saliva and root canals of teeth associated with apical periodontitis due to endodontic treatment failure in the same patient. Study Design: Cross-sectional comparative study. Place and Duration of Study: Samples were collected from Operative Dentistry Department, AFID, while laboratory processing was done at AFIP, Rawalpindi. Study duration was one year. Patients and Methods: Fifty patients, both males and females with failed endodontic treatment were selected. Saliva and root canal samples were collected from each patient, inoculated on MacKonkey agar plate and incubated at 35-37 degree C for 48 hrs. E. faecalis colonies were identified by colony morphology, gramstain, catalase, bile asculin test, arabinose fermentation and growth in 6% NaCl nutrient broth. Results: The frequency of E. faecalis in saliva was 34% and in root canal it was 58%. Frequency between the presence of E. faecalis in root canals and saliva was found to be statistically different (p = 0.001). Conclusion: The presence of E. faecalis in root canal was not associated with their presence in saliva. (author)

  7. Frequency of enterococcus faecalis in saliva and root canals with treatment failure

    International Nuclear Information System (INIS)

    Shan, T.; Manzoor, M.A.; Hussain, W.

    2014-01-01

    To compare the frequency of E.faecalis in the saliva and root canals of teeth associated with apical periodontitis due to endodontic treatment failure Study. Design: Cross-sectional comparative. Place and Duration of Study: Samples were collected from Operative Dentistry department, AFID, while laboratory processing was done at AFIP, Rawalpindi. Duration of this study was one year. Patients and Method: Fifty patients, both males and females with failed endodontic treatment were selected. Saliva and root canal samples were collected from each patient, inoculated on MacKonkey agar plate and incubated at 35-370 C for 48 hours. E.faecalis colonies were identified by colony morphology, Gram stain, catalase, bile asculin test, arabinose fermentation and growth in 6% NaCl nutrient broth. Results: The frequency of E.faecalis in saliva was 34% and 58% in root canal samples. Frequency of the presence of E.faecalis in root canals and saliva was found to be statistically different (p=0.000). Conclusion: The presence of E.faecalis in root canal was not associated with their presence in saliva. (author)

  8. Inhibition effect of calcium hydroxide point and chlorhexidine point on root canal bacteria of necrosis teeth

    Directory of Open Access Journals (Sweden)

    Andry Leonard Je

    2006-03-01

    Full Text Available Calcium Hydroxide point and Chlorhexidine point are new drugs for eliminating bacteria in the root canal. The points slowly and controly realease Calcium Hydroxide and Chlorhexidine into root canal. The purpose of the study was to determined the effectivity of Calcium hydroxide point (Calcium hydroxide plus point and Chlorhexidine point in eleminating the root canal bacteria of nescrosis teeth. In this study 14 subjects were divided into 2 groups. The first group was treated with Calcium hydroxide point and the second was treated with Chlorhexidine poin. The bacteriological sampling were measured with spectrofotometry. The Paired T Test analysis (before and after showed significant difference between the first and second group. The Independent T Test which analysed the effectivity of both groups had not showed significant difference. Although there was no significant difference in statistical test, the result of second group eliminate more bacteria than the first group. The present finding indicated that the use of Chlorhexidine point was better than Calcium hydroxide point in seven days period. The conclusion is Chlorhexidine point and Calcium hydroxide point as root canal medicament effectively eliminate root canal bacteria of necrosis teeth.

  9. Effectiveness of castor oil extract on Escherichia coli and its endotoxins in root canals.

    Science.gov (United States)

    Valera, Marcia Carneiro; Maekawa, Lilian Eiko; Chung, Adriana; de Oliveira, Luciane Dias; Carvalho, Claudio Antonio Talge; Koga-Ito, Cristiane Yumi; Jorge, Antonio Olavo Cardoso

    2012-01-01

    This in vitro study sought to evaluate the effectiveness of castor oil extract used as an irrigating solution on Escherichia coli and its endotoxins in root canals. Sixty single-rooted teeth were prepared (using castor oil extract as irrigating solution) and divided into five groups (n = 12): Group 1 samples were treated with calcium hydroxide (Ca(OH)2), Group 2 samples were treated with polymyxin B, Group 3 samples were treated with Ca(OH)2 and 2% chlorhexidine gel (CHX), and Group 4 samples were treated with castor oil extract. A control group used physiological saline solution as an irrigant. Canal content samples were collected at four different times: immediately after instrumentation, seven days after instrumentation, after 14 days of intracanal medication, and seven days after removal of intracanal medication. A plating method was used to assess antimicrobial activity and the quantification of endotoxins was evaluated by the chromogenic Limulus lysate assay. Data were submitted to ANOVA and a Dunn test (a = 5%). Irrigation with castor oil extract decreased E. coli counts but had no effect on the level of endotoxins. Samples taken seven days after removal of medication revealed a significant reduction in endotoxin levels in Groups 3 and 4. Compared to the saline solution irrigation, castor oil extract decreased microorganism counts in root canals immediately after canal preparation. None of the medications used completely eliminated endotoxins in the root canal.

  10. Dimensions of the lumbar spinal canal: variations and correlations with somatometric parameters using CT

    Energy Technology Data Exchange (ETDEWEB)

    Karantanas, A.H. [Department of CT-MRI, Larissa General Hospital (Greece); Zibis, A.H.; Papaliaga, M.; Georgiou, E.; Rousogiannis, S. [Larissa Medical School, University of Thessaly, Larissa (Greece)

    1998-12-01

    The aim of this study was to investigate the correlation of vertebral dimensions with somatometric parameters in patients without clinical symptoms and radiological signs of central lumbar spinal stenosis. One hundred patients presenting with low back pain or sciatica were studied with CT. In each of the L3, L4 and L5 vertebra three slices were taken with the following measurements: 1. Slice through the intervertebral disc: (a) spinal canal area; (b) interarticular diameter; (c) interligamentous diameter. 2. Slice below the vertebral arcus: (a) dural sac area; (b) vertebral body area. 3. Pediculolaminar level: (a) anteroposterior diameter and interpedicular diameter of the spinal canal; (b) spinal canal area; (c) width of the lateral recesses. The Jones-Thomson index was also estimated. The results of the present study showed that there is a statistically significant correlation of height, weight and age with various vertebral indices. The conventional, widely accepted, anteroposterior diameter of 11.5 mm of the lumbar spinal canal is independent of somatometric parameters, and it is the only constant measurement for the estimation of lumbar spinal stenosis with a single value. The present study suggests that there are variations of the dimensions of the lumbar spinal canal and correlations with height, weight and age of the patient. (orig.) With 1 fig., 6 tabs., 24 refs.

  11. Dimensions of the lumbar spinal canal: variations and correlations with somatometric parameters using CT

    International Nuclear Information System (INIS)

    Karantanas, A.H.; Zibis, A.H.; Papaliaga, M.; Georgiou, E.; Rousogiannis, S.

    1998-01-01

    The aim of this study was to investigate the correlation of vertebral dimensions with somatometric parameters in patients without clinical symptoms and radiological signs of central lumbar spinal stenosis. One hundred patients presenting with low back pain or sciatica were studied with CT. In each of the L3, L4 and L5 vertebra three slices were taken with the following measurements: 1. Slice through the intervertebral disc: (a) spinal canal area; (b) interarticular diameter; (c) interligamentous diameter. 2. Slice below the vertebral arcus: (a) dural sac area; (b) vertebral body area. 3. Pediculolaminar level: (a) anteroposterior diameter and interpedicular diameter of the spinal canal; (b) spinal canal area; (c) width of the lateral recesses. The Jones-Thomson index was also estimated. The results of the present study showed that there is a statistically significant correlation of height, weight and age with various vertebral indices. The conventional, widely accepted, anteroposterior diameter of 11.5 mm of the lumbar spinal canal is independent of somatometric parameters, and it is the only constant measurement for the estimation of lumbar spinal stenosis with a single value. The present study suggests that there are variations of the dimensions of the lumbar spinal canal and correlations with height, weight and age of the patient. (orig.)

  12. Visibility of the mandibular canal and the mental foramen in panoramic radiography

    International Nuclear Information System (INIS)

    Jeong, Seon Jin; Choi, Eui Hwan; Kim, Jae Duk

    2001-01-01

    To determine the head position that the superior border of the mandibular canal as well as mental foramen can be more clearly visualized in panoramic radiography. Ten dry mandibles were radiography bilaterally using PM 2002 CC panoramic machine. A 20 mm thick aluminium filter was added to the slit collimator to obtain radiographs with acceptable density. The specimens were tilted by 2, 4, 6, 8 and 10 degrees downward with and without radiopaque markers. Radiopaque markers were inserted into the mandibular canals and the mental canals of each side of the specimens to serve as reference image when assessing the radiographs. The obtained results were analyzed statistically. Mandibular canals were significantly more clearly visible in the radiographs with 4 and 6 degree downward position on both sides (P<0.05). Mental foramen were significantly more clearly visible in the was not significant difference between right and left sides. Panoramic radiographs with 4 to 6 degree downward tilting could be valuable in locating the mandibular canal as well as the mental foramen

  13. 33 CFR 207.590 - Black Rock Canal and Lock at Buffalo, N.Y.; use, administration, and navigation.

    Science.gov (United States)

    2010-07-01

    ... Buffalo, N.Y.; use, administration, and navigation. 207.590 Section 207.590 Navigation and Navigable... Black Rock Canal and Lock at Buffalo, N.Y.; use, administration, and navigation. (a) The term “canal... immediately to the Black Rock Lock, foot of Bridge Street, Buffalo, N.Y., telephone 876-5454. (k) Ferry Street...

  14. Meatoplasty in Canal wall down Surgery: Our Experience and Literature Review

    Directory of Open Access Journals (Sweden)

    Faramarz Memari

    2017-01-01

    Full Text Available Introduction: Meatoplasty is the final and essential step in performing effective canal wall down surgery for chronic otitis media. In this article we review some previous techniques and discuss our preferred method. Materials and Methods: In this observational case series study, we used this technique in 53 patients (28 male and 25 female between January 2005 and January 2008. Our survey was completed in 31 patients. Results: Twenty-six patients (83.9% said their ear appeared normal after the procedure, but five patients (16.1% complained of some minor change in the shape of their ear. Twenty-nine patients (93.5% had a completely wide ear canal. The ear canal had some degree of stenosis in two patients (6.5% post-operatively. Conclusion: This technique offers good functional and cosmetic results with minimal manipulation and minimal anatomic disruption.

  15. Mandibular second molar with 3 mesial canals and a radix paramolaris

    Directory of Open Access Journals (Sweden)

    N Ragavendran

    2014-01-01

    Full Text Available Mandibular first molar commonly has two roots, the mesial and the distal root. Surprisingly in some mandibular first molar has an unusual extra third root in between mesial and distal root. This extra root is the most commonly seen in lingual side and is called as radix entomolaris. If this extra root is seen on the buccal side, it is termed as radix paramolaris (RP, which is a very rare phenomenon. Recently, various case report studies has shown the presence of third canal in the mesial and distal roots of mandibular molars. They are named as middle mesial and middle distal canal, respectively. Here, we present a case report of mandibular second molar showing three canals in the mesial root and a RP.

  16. A comparison of the effectiveness of chloroform and eucalyptus oil in dissolving root canal sealers.

    Science.gov (United States)

    Schäfer, Edgar; Zandbiglari, Tannaz

    2002-05-01

    The solubility of 8 different root canal sealers in chloroform and in eucalyptus oil was compared. For standardized samples (n=12), ring molds were filled with mixed sealers based on epoxy resin, silicone, calcium hydroxide, zinc oxide-eugenol, glass ionomer, and polyketone. These samples were immersed in chloroform or eucalyptus oil for 30 seconds, 1 minute, 2 minutes, 5 minutes, 10 minutes, and 20 minutes. Then, the mean weight loss was determined and statistically analyzed. With the exception of the silicone, all the sealers showed significantly higher solubilities (P <.05) in chloroform than in eucalyptus oil. Epoxy resin was the most soluble sealer in chloroform. In eucalyptus oil, calcium hydroxide, and zinc oxide-eugenol showed the highest solubility. Under the conditions of this study, chloroform was a far more effective solvent of root canal sealers than eucalyptus oil. Because of the potential hazards of chloroform, further studies on the dissolution of root canal sealers in different solvents seem to be necessary.

  17. Diagnostic value of saccoradiculography and of cat scan to detect stenosis of the lumbar canal

    International Nuclear Information System (INIS)

    Arrault, I.; Benoist, M.; Rocolle, J.; Busson, J.; Lassale, B.; Deburge, A.

    1987-01-01

    Radiculographic X-rays and CAT scans of 60 patients operated on for stenosis of the lumbar canal were analysed separately and retrospectively by rheumatologists, a radiologist and surgeons working jointly, without knowledge of findings revealed by surgery. Comparison of findings with a detailed surgical report reveals that in the case of central lumbar canal stenosis, CAT scan provides a higher degree of reliability (72%) in diagnosis than does radiculography (56%). With lateral stenosis of the lateral cleft, reliability of both tests is identical (62%). The diagnostic deficiencies of these two examinations are discussed as well as diagnostic criteria employed and possible avenues of research. Currently, in the case of stenosis of the lumbar canal, it is still necessary to perform both of these examinations in combination and to accept the fact that, in certain cases, only one of the two tests reveals the stenosis, to be able to attain a preoperative rate of correct diagnosis greater than 80% [fr

  18. Environmental Assessment and Finding of No Significant Impact - Mckay Bypass Canal Extension

    Energy Technology Data Exchange (ETDEWEB)

    N/A

    1998-09-01

    The Department of Energy (DOE) has prepared an environmental assessment (EA) (DOE/EA-1262) to extend the McKay Bypass Canal on the east side of the Rocky Flats Environmental Technology Site (Site), located north of Golden, Colorado. The McKay Bypass Canal Extension (Extension) is needed to route water from the existing canal around the Walnut Creek drainage, thus preventing potential co-mingling of Broomfield city water (collected from the Coal Creek drainage) with Site runoff water. The EA describes and analyzes the environmental effects of the Proposed Action (using a buried pipeline for the extension), and the alternatives of taking no action, using an open ditch for the extension, and using an aboveground pipeline for the extension. The EA was the subject of a public comment period from July 22 to August 6, 1998. Written comments regarding the EA were received from the City of Broomfield and the Colorado Department of Public Health and Environment.

  19. Comparative study of single and multislice computed tomography for assessment of the mandibular canal

    Directory of Open Access Journals (Sweden)

    Adriana da Silva Ferreira Paes

    2007-06-01

    Full Text Available OBJECTIVE: The purpose of this study was to evaluate the accuracy of relative measurements from the roof of the mandibular canal to the alveolar crest in multislice (multidetector computed tomography (MDCT and single-slice computed tomography (SSCT. MATERIAL AND METHODS: The sample consisted of 26 printed CT films (7 SSCT and 19 MDCT from the files of the LABI-3D (3D Imaging Laboratory of the School of Dentistry of the University of São Paulo (FOUSP, which had been acquired using different protocols. Two observers analyzed in a randomized and independent order a series of 22 oblique CT reconstructions of each patient. Each observer analyzed the CT scans twice. The length of the mandibular canal and the distance between the mandibular canal roof and the crest of the alveolar ridge were obtained. Dahlberg test was used for statistical analysis. RESULTS: The mean error found for the mandibular canal length measurements obtained from SSCT was 0.53 mm in the interobserver analysis, and 0.38 mm for both observers. On MDCT images, the mean error was 0.0 mm in the interobserver analysis, and 0.0 and 0.23 mm in the intraobserver analysis. Regarding the distance between the mandibular canal roof and the alveolar bone crest, the SSCT images showed a mean error of 1.16 mm in the interobserver analysis and 0.66 and 0.59 mm in the intraobserver analysis. In the MDCT images, the mean error was 0.72 mm in the interobserver analysis and 0.50 and 0.54 mm in the intraobserver analysis. CONCLUSION: Multislice CT was demonstrated a more accurate method and demonstrated high reproducibility in the analysis of important anatomical landmarks for planning of mandibular dental implants, namely the mandibular canal pathway and alveolar crest height.

  20. Computed tomography in lumbar canal stenosis. Relationship between its findings and clinical symptoms

    Energy Technology Data Exchange (ETDEWEB)

    Ohta, Shu; Baba, Itsushi; Ishida, Akihisa; Sumida, Tadayuki; Sasaki, Seishu (Hiroshima Shiritsu Asa Shimin Hospital (Japan))

    1984-09-01

    Preoperative CT was done in 39 patients with lumbar canal stenosis. Marked symmetrical narrowing of the whole vertebral canal was seen in the group with nervous symptoms in the cauda equina. Deformed bilateral intervertebral joints were seen in the group with both nervous symptoms in the cauda equina and radicular sciatica. The lateral recess on the affected side was markedly narrowed by the projection of the upper and lower joints and herniation. In the group with radicular sciatica, the vertebral canal itself was not so narrowed, but the unilateral intervertebral joint was extremely deformed, causing a narrowing of the lateral recess. There were large differences in the angle of the left and right intervertebral joints.

  1. Observation of positional relation between mandibular third molars and the mandibular canal on limited cone beam computed tomography

    International Nuclear Information System (INIS)

    Hashizume, Atsuko; Nakagawa, Yoichi; Ishii, Hisako; Kobayashi, Kaoru

    2004-01-01

    We describe the preoperative use of limited cone beam computed tomography (CT) with a dental CT scanner for the assessment of mandibular third molars before extraction. Cone beam CT provides 42.7-mm-high and 30-mm-wide rectangular solid images, with a resolution of less than 0.2 mm. The positional relationship between the mandibular third molars and the mandibular canal was examined by dental CT. Sixty-eight lower third molars of 62 patients whose teeth were superimposed on the mandibular canal on periapical or panoramic radiographs were studied. Dental CT scans clearly demonstrated the positional relationship between the mandibular canal and the teeth. The mandibular canal was located buccally to the roots of 16 teeth, lingually to the roots of 27 teeth, inferiorly to the roots of 23 teeth, and between the roots of 2 teeth. The presence of bone between the mandibular canal and the teeth was not noted in 7 of 16 buccal cases, 24 of 27 lingual cases, and 10 of 23 inferior cases on dental CT scans, suggesting that the canal was in contact with the teeth. Fifty-nine of the 68 mandibular third molars were surgically removed, and postoperative transient hypoesthesia occurred in 4 patients. Dental CT scans showed no bone between the mandibular canal and the teeth in all 4 patients. Hypoesthesia was not related to the bucco-lingual location of the mandibular canal or to the extent of bone loss between the canal and the teeth. However, hypoesthesia did not occur in patients with bone between the mandibular canal and the teeth. Thus, information on the distance between the canal and teeth on dental CT scans was useful for predicting the risk of inferior alveolar nerve damage. Because of its high resolution and low radiation dose, cone beam CT was useful for examination before mandibular third molar surgery. (author)

  2. Predictors, prevention, and management of postoperative pain associated with nonsurgical root canal treatment: A systematic review

    Directory of Open Access Journals (Sweden)

    Mothanna K. AlRahabi, PhD

    2017-10-01

    Full Text Available Postoperative pain after root canal treatment can be reduced by applying recent advances in endodontic techniques and equipment. This systematic review includes current knowledge about pain after nonsurgical root canal treatment, including predictors, related factors, effects of recent advances, and management. A literature search was performed using the PubMed, ScienceDirect, and Cochrane Library databases for articles published between 1990 and 2016. Search keywords included postoperative pain, nonsurgical treatment, single visit, recent advances in endodontics, and management of postoperative pain with endodontic treatment. Only original research studies were included; editorials, reviews, brief notes, conference proceedings, and letters to the editor were excluded. The initial search yielded 4941 articles, which were assessed and filtered using the selection criteria. Sixty-five studies met the inclusion criteria and were included in the review. The findings showed that pain after nonsurgical root canal treatment occurred in 3–69.3% of patients. Microorganisms were identified as the primary contributors to postoperative pain, and there was no significant difference in postoperative pain between single- and multiple-visit treatments. Postoperative pain after root canal treatment ranges from mild to moderate and occurs even after optimally performed procedures. Furthermore, adequate management of postoperative pain is often considered an indicator of clinical excellence. Application of recently developed endodontic techniques and devices will reduce postoperative pain. Furthermore, a flexible, severity-based drug administration plan can be used to control and manage pain after root canal treatment. Application of the current research findings will reduce pain following root canal treatment and improve patient outcomes.

  3. Comparison of antimicrobial activity of traditional and new developed root sealers against pathogens related root canal

    Directory of Open Access Journals (Sweden)

    Joo-Hee Shin

    2018-03-01

    Full Text Available Background/purpose: Bacterial infection is closely associated with the failure of endodontic treatment, and use of endodontic sealer with antimicrobial activity and biological compatibility is necessary for the success of root canal treatment. The purpose of this study was to investigate and to compare the antibacterial effect of two calcium silicate-based root canal sealers (Endoseal and EndoSequence BC sealer as recent development sealers and with three conventional root canal sealers (AH Plus, Sealapex, and Tubli-Seal, before or after setting, on Porphyromonas endodontalis, Porphyromonas gingivalis, and Enterococcus faecalis. Materials and methods: The sealers were soaked in phosphate buffered saline to elute its compositions after and before setting, and the elutes were performed the antimicrobial assay. Also, X-ray fluorescence analysis was carried out to compare compositions of two calcium silicate-based sealers. Results: The conventional root canal sealers have strong antibacterial activity against the Gram-negative bacteria, P. endodontalis and P. gingivalis. Endoseal sealer showed antibacterial activity against not only the Gram-negative bacteria, but also against the Gram-positive bacteria, E. faecalis. However, Endosequence BC sealer exhibited a weak antibacterial effect on all bacteria in this study. X-ray fluorescence analysis exhibited that Endoseal contained more types and more amount of the oxide compound known to have strong antimicrobial activity such as Al2O3, Fe2O3, MgO, Na2O, NiO, and SO2 than Endoseqeunce BC. Conclusion: Endoseal, which contains various types of oxide compounds, seems to be a suitable sealer for preventing bacterial infection in both treated and untreated root canals. Keywords: Root canal sealer, Antimicrobial activity, Oxide compound, E. faecalis

  4. Simulation of the effects of proposed tide gates on circulation, flushing, and water quality in residential canals, Cape Coral Florida

    Science.gov (United States)

    Goodwin, Carl R.

    1991-01-01

    Decades of dredging and filling of Florida's low-lying coastal wetlands have produced thousands of miles of residential tidal canals and adjacent waterfront property. Typically, these canals are poorly flushed, and over time, accumulated organic-rich bottom materials, contribute to an increasingly severe degraded water quality. One-dimensional hydrodynamic and constituent-transport models were applied to two dead-end canal systems to determine the effects of canal system interconnection using tide gates on water circulation and constituent flushing. The model simulates existing and possible future circulation and flushing conditions in about 29 miles of the approximately 130 miles of tidally influenced canals in Cape Coral, located on the central west coast of peninsular Florida. Model results indicate that tidal water-level differences between the two canal systems can be converted to kinetic energy, in the form of increased water circulation, but the use of one-way tide gate interconnections. Computations show that construction of from one to four tide gates will cause replacement of a volume of water equivalent to the total volume of canals in both systems in 15 to 9 days, respectively. Because some canals flush faster than others, 47 and 21 percent of the original canal water will remain in both systems 50 days after start of operation of one and four tide gates, respectively. Some of the effects that such increased flushing are expected to have include reduced density stratification and associated dissolved-oxygen depletion in canal bottom waters, increased localized reaeration, and more efficient discharge of stormwater runoff entering the canals.

  5. Effects of adductor-canal-blockade on pain and ambulation after total knee arthroplasty

    DEFF Research Database (Denmark)

    Jenstrup, M T; Jæger, P; Lund, J

    2012-01-01

    Total knee arthroplasty (TKA) is associated with intense post-operative pain. Besides providing optimal analgesia, reduction in side effects and enhanced mobilization are important in this elderly population. The adductor-canal-blockade is theoretically an almost pure sensory blockade. We hypothe...... hypothesized that the adductor-canal-blockade may reduce morphine consumption (primary endpoint), improve pain relief, enhance early ambulation ability, and reduce side effects (secondary endpoints) after TKA compared with placebo.......Total knee arthroplasty (TKA) is associated with intense post-operative pain. Besides providing optimal analgesia, reduction in side effects and enhanced mobilization are important in this elderly population. The adductor-canal-blockade is theoretically an almost pure sensory blockade. We...

  6. Triple –E Vessels: Tonnage Measurement and Suez Canal Dues Assessment

    Directory of Open Access Journals (Sweden)

    Elsayed Hussein Galall

    2015-08-01

    Full Text Available Container is growing faster than GDP, Shipping lines always attempt to augment efficiencyby reducing cost and by attracting larger volumes of containers. As a result rising containerfreight rates the lines have been driven to increase economic of scale, by building mega shipsand fewer mere efficient port calls. In 2011 Maersk line ordered up to 20 new “Triple- E “Class of container vessels deliversbetween 2013- 2015. These class of mega container vessels have its way through Suez Canal,other companies CMA, CGM also ordered this type of mega container vessels, in order toreach higher profits due to the achieved economics of scale It is believed that 20000 TEUcould be the next target size. Present mega container fleet and any future feasible potential vessel capacity expansionmore than 18000 TEU put Suez Canal route in strong competitive position. MeanwhilePanama Canal will not be able to handle vessels larger than 12600 TEU even after itsexpansion in 2015.

  7. Narrow duplicated internal auditory canal: radiological findings and review of the literature

    International Nuclear Information System (INIS)

    Demir, Oezguen Ilhan; Cakmakci, Handan; Men, Sueleyman; Erdag, Taner Kemal

    2005-01-01

    Narrow duplicated internal auditory canal (IAC) is a rare malformation of the temporal bone that is associated with ipsilateral congenital sensorineural hearing loss. This may be an isolated finding or a part of a syndrome. Radiological examination should demonstrate aplasia or hypoplasia of the neural components of the narrow IAC, to guide the surgical approach. We report a 7-year-old boy with Klippel-Feil syndrome with a narrow double IAC with no sensorineural hearing loss but with conductive hearing loss. In this patient, the IAC consisted of two separate narrow bony canals clearly seen on 3D temporal bone CT and one nerve that was delineated on MRI. The contralateral external auditory canal was stenotic and the ossicles were dysplastic. (orig.)

  8. Pulp revascularization after root canal decontamination with calcium hydroxide and 2% chlorhexidine gel.

    Science.gov (United States)

    Soares, Adriana de Jesus; Lins, Fernanda Freitas; Nagata, Juliana Yuri; Gomes, Brenda Paula Figueiredo de Almeida; Zaia, Alexandre Augusto; Ferraz, Caio Cezar Randi; de Almeida, José Flávio Affonso; de Souza-Filho, Francisco José

    2013-03-01

    Pulp revascularization may be considered a promising alternative for necrotic immature teeth. Many studies have accomplished passive decontamination associated with an antibiotic paste. To date, there is no report evaluating calcium hydroxide associated with 2% chlorhexidine gel for revascularization therapy. The aim of this case report was to describe a new proposal for pulp revascularization with mechanical decontamination and intracanal medication composed of calcium hydroxide and 2% chlorhexidine gel. The patient, a 9-year-old girl, suffered an intrusion associated with pulp exposure caused by an enamel-dentin fracture in her maxillary left central incisor. After diagnosis, treatment consisted of revascularization therapy with gentle manual instrumentation of the cervical and medium thirds of the root in addition to intracanal medication with calcium hydroxide and 2% chlorhexidine gel for 21 days. In the second session, a blood clot was stimulated up to the cervical third of the root canal. Mineral trioxide aggregate (MTA; Angelus, Londrina, Paraná, Brazil) was used for cervical sealing of the canal. Coronal sealing was performed with temporary filling material and composite resin. During the follow-up period, the root canal space showed a progressive decrease in width, mineralized tissue deposition on root canal walls, and apical closure. A cone-beam computed tomography scan taken at the 2-year follow-up confirmed these findings and did not show complete root canal calcification. This new proposal for revascularization therapy with 2% chlorhexidine gel may be used for the treatment of necrotic immature root canals. Copyright © 2013 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  9. Capturing Flow-weighted Water and Suspended Particulates from Agricultural Canals During Drainage Events.

    Science.gov (United States)

    Bhadha, Jehangir H; Sexton, Anne; Lang, Timothy A; Daroub, Samira H

    2017-11-07

    The purpose of this study is to describe the methods used to capture flow-weighted water and suspended particulates from farm canals during drainage discharge events. Farm canals can be enriched by nutrients such as phosphorus (P) that are susceptible to transport. Phosphorus in the form of suspended particulates can significantly contribute to the overall P loads in drainage water. A settling tank experiment was conducted to capture suspended particulates during discrete drainage events. Farm canal discharge water was collected in a series of two 200 L settling tanks over the entire duration of the drainage event, so as to represent a composite subsample of the water being discharged. Imhoff settling cones are ultimately used to settle out the suspended particulates. This is achieved by siphoning water from the settling tanks via the cones. The particulates are then collected for physico-chemical analyses.

  10. Cleaning lateral morphological features of the root canal: the role of streaming and cavitation.

    Science.gov (United States)

    Robinson, J P; Macedo, R G; Verhaagen, B; Versluis, M; Cooper, P R; van der Sluis, L W M; Walmsley, A D

    2018-01-01

    To investigate the effects of ultrasonic activation file type, lateral canal location and irrigant on the removal of a biofilm-mimicking hydrogel from a fabricated lateral canal. Additionally, the amount of cavitation and streaming was quantified for these parameters. An intracanal sonochemical dosimetry method was used to quantify the cavitation generated by an IrriSafe 25 mm length, size 25 file inside a root canal model filled with filtered degassed/saturated water or three different concentrations of NaOCl. Removal of a hydrogel, demonstrated previously to be an appropriate biofilm mimic, was recorded to measure the lateral canal cleaning rate from two different instruments (IrriSafe 25 mm length, size 25 and K 21 mm length, size 15) activated with a P5 Suprasson (Satelec) at power P8.5 in degassed/saturated water or NaOCl. Removal rates were compared for significant differences using nonparametric Kruskal-Wallis and/or Mann-Whitney U-tests. Streaming was measured using high-speed particle imaging velocimetry at 250 kfps, analysing both the oscillatory and steady flow inside the lateral canals. There was no significant difference in amount of cavitation between tap water and oversaturated water (P = 0.538), although more cavitation was observed than in degassed water. The highest cavitation signal was generated with NaOCl solutions (1.0%, 4.5%, 9.0%) (P streaming. The oscillatory velocities were higher inside the lateral canal 3 mm compared to 6 mm from WL and were higher for NaOCl than for saturated water, which in turn was higher than for degassed water. Measurements of cavitation and acoustic streaming have provided insight into their contribution to cleaning. Significant differences in cleaning, cavitation and streaming were found depending on the file type and size, lateral canal location and irrigant used. In general, the IrriSafe file outperformed the K-file, and NaOCl performed better than the other irrigants tested. The cavitation and

  11. The dimensions of the tarsal sinus and canal in different foot positions and its clinical implications

    NARCIS (Netherlands)

    Kleipool, R. P.; Blankevoort, L.; Ruijter, J. M.; Kerkhoffs, G. M. M. J.; Oostra, R. J.

    2017-01-01

    This study presents a reference for the dimensions of the tarsal sinus and canal in healthy adults in different foot positions to facilitate understanding of the kinematics of the subtalar joint, the effect of an implant, and other clinical issues. In a 3D CT stress test on 20 subjects, the right

  12. 33 CFR 207.440 - St. Marys Falls Canal and Locks, Mich.; use, administration, and navigation.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false St. Marys Falls Canal and Locks... CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE NAVIGATION REGULATIONS § 207.440 St... include all of the natural waters of the St. Marys River on the U.S. side of the International Boundary...

  13. Ectopic external auditory canal and ossicular formation in the oculo-auriculo-vertebral spectrum

    Energy Technology Data Exchange (ETDEWEB)

    Supakul, Nucharin [Indiana University School of Medicine, Department of Radiology, Indianapolis, IN (United States); Ramathibodi Hospital, Mahidol University, Department of Diagnostic and Therapeutic Radiology, Bangkok (Thailand); Kralik, Stephen F. [Indiana University School of Medicine, Department of Radiology, Indianapolis, IN (United States); Ho, Chang Y. [Indiana University School of Medicine, Department of Radiology, Indianapolis, IN (United States); Riley Children' s Hospital, MRI Department, Indianapolis, IN (United States)

    2015-07-15

    Ear abnormalities in oculo-auricular-vertebral spectrum commonly present with varying degrees of external and middle ear atresias, usually in the expected locations of the temporal bone and associated soft tissues, without ectopia of the external auditory canal. We present the unique imaging of a 4-year-old girl with right hemifacial microsomia and ectopic location of an atretic external auditory canal, terminating in a hypoplastic temporomandibular joint containing bony structures with the appearance of auditory ossicles. This finding suggests an early embryological dysfunction involving Meckel's cartilage of the first branchial arch. (orig.)

  14. Comparative study of six rotary nickel-titanium systems and hand instrumentation for root canal preparation.

    Science.gov (United States)

    Guelzow, A; Stamm, O; Martus, P; Kielbassa, A M

    2005-10-01

    To compare ex vivo various parameters of root canal preparation using a manual technique and six different rotary nickel-titanium (Ni-Ti) instruments (FlexMaster, System GT, HERO 642, K3, ProTaper, and RaCe). A total of 147 extracted mandibular molars were divided into seven groups (n = 21) with equal mean mesio-buccal root canal curvatures (up to 70 degrees), and embedded in a muffle system. All root canals were prepared to size 30 using a crown-down preparation technique for the rotary nickel-titanium instruments and a standardized preparation (using reamers and Hedströem files) for the manual technique. Length modifications and straightening were determined by standardized radiography and a computer-aided difference measurement for every instrument system. Post-operative cross-sections were evaluated by light-microscopic investigation and photographic documentation. Procedural errors, working time and time for instrumentation were recorded. The data were analysed statistically using the Kruskal-Wallis test and the Mann-Whitney U-test. No significant differences were detected between the rotary Ni-Ti instruments for alteration of working length. All Ni-Ti systems maintained the original curvature well, with minor mean degrees of straightening ranging from 0.45 degrees (System GT) to 1.17 degrees (ProTaper). ProTaper had the lowest numbers of irregular post-operative root canal diameters; the results were comparable between the other systems. Instrument fractures occurred with ProTaper in three root canals, whilst preparation with System GT, HERO 642, K3 and the manual technique resulted in one fracture each. Ni-Ti instruments prepared canals more rapidly than the manual technique. The shortest time for instrumentation was achieved with System GT (11.7 s). Under the conditions of this ex vivo study all Ni-Ti systems maintained the canal curvature, were associated with few instrument fractures and were more rapid than a standardized manual technique. Pro

  15. Occurrence and distribution of bacterial indicators and pathogens in canal communities along the Texas coast.

    Science.gov (United States)

    Goyal, S M; Gerba, C P; Melnick, J L

    1977-08-01

    Increased construction of residential canal communities along the southern coastline of the United States has led to a concern about their impact on water quality. Pollution of such dead-end canals is potentially hazardous because of their heavy usage for recreational activities. Coliforms, fecal coliforms, and salmonellae in the surface water and bottom sediments of six selected residential coastal canals were monitored over a period of 17 months. No statistically significant relationship was observed between the organism concentrations and temperature, pH, turbidity, and suspended solids content of water. An inverse relationship between the concentration of indicator organism and salinity of water was found, however, to occur at a 99.9% level of significance. All of the microorganisms studied were found to be present in greater numbers in sediments than in the overlying water, often by a factor of several logs. Heavy rainfall resulted in large increases in the number of organisms in both water and sediment samples. Our results indicate that bottom sediments in the shallow canal systems can act as reservoirs of enteric bacteria, which may be resuspended in response to various environmental factors and recreational activities.

  16. Internal carotid arterial canal size and scaling in Euarchonta: Re-assessing implications for arterial patency and phylogenetic relationships in early fossil primates.

    Science.gov (United States)

    Boyer, Doug M; Kirk, E Christopher; Silcox, Mary T; Gunnell, Gregg F; Gilbert, Christopher C; Yapuncich, Gabriel S; Allen, Kari L; Welch, Emma; Bloch, Jonathan I; Gonzales, Lauren A; Kay, Richard F; Seiffert, Erik R

    2016-08-01

    Primate species typically differ from other mammals in having bony canals that enclose the branches of the internal carotid artery (ICA) as they pass through the middle ear. The presence and relative size of these canals varies among major primate clades. As a result, differences in the anatomy of the canals for the promontorial and stapedial branches of the ICA have been cited as evidence of either haplorhine or strepsirrhine affinities among otherwise enigmatic early fossil euprimates. Here we use micro X-ray computed tomography to compile the largest quantitative dataset on ICA canal sizes. The data suggest greater variation of the ICA canals within some groups than has been previously appreciated. For example, Lepilemur and Avahi differ from most other lemuriforms in having a larger promontorial canal than stapedial canal. Furthermore, various lemurids are intraspecifically variable in relative canal size, with the promontorial canal being larger than the stapedial canal in some individuals but not others. In species where the promontorial artery supplies the brain with blood, the size of the promontorial canal is significantly correlated with endocranial volume (ECV). Among species with alternate routes of encephalic blood supply, the promontorial canal is highly reduced relative to ECV, and correlated with both ECV and cranium size. Ancestral state reconstructions incorporating data from fossils suggest that the last common ancestor of living primates had promontorial and stapedial canals that were similar to each other in size and large relative to ECV. We conclude that the plesiomorphic condition for crown primates is to have a patent promontorial artery supplying the brain and a patent stapedial artery for various non-encephalic structures. This inferred ancestral condition is exhibited by treeshrews and most early fossil euprimates, while extant primates exhibit reduction in one canal or another. The only early fossils deviating from this plesiomorphic

  17. Shaping ability of NT Engine and McXim rotary nickel-titanium instruments in simulated root canals. Part 2.

    Science.gov (United States)

    Thompson, S A; Dummer, P M

    1997-07-01

    The aim of this laboratory-based study was to determine the shaping ability of NT Engine and McXim nickel-titanium rotary instruments in simulated root canals. A total of 40 canals with four different shapes in terms of angle and position of curve were prepared with NT Engine and McXim instruments, using the technique recommended by the manufacturer. Part 2 of this report describes the efficacy of the instruments in terms of prevalence of canal aberrations, the amount and direction of canal transportation and overall postoperative shape. Pre- and postoperative images of the canals were taken using a video camera attached to a computer with image analysis software. The pre- and postoperative views were superimposed to highlight the amount and position of material removed during preparation. No zips, elbows, perforations or danger zones were created during preparation. Forty-two per cent of canals had ledges on the outer aspect of the curve, the majority of which (16 out of 17) occurred in canals with short acute curves. There were significant differences (P Engine and McXim rotary nickel-titanium instruments created no aberrations other than ledges and produced only minimal transportation. The overall shape of canals was good.

  18. Definition and endodontic treatment of dilacerated canals: a survey of Diplomates of the American Board of Endodontics.

    Science.gov (United States)

    Dastmalchi, Nafiseh; Kazemi, Zeinab; Hashemi, Siroos; Peters, Ove A; Jafarzadeh, Hamid

    2011-01-01

    To gather data from Diplomates of the American Board of Endodontics regarding treatment of dilacerated canals. A questionnaire addressing definition, endodontic treatment procedures and prognosis was constructed and distributed via e-mail to 708 Diplomates of the American Board of Endodontics. Data from 150 respondents, a 21% response rate, were collected by using a Web-based interface. For statistical analysis, Chi-square tests were used. More than 25% of respondents believed that a dilacerated root should have a curvature > 40°. One-visit treatment is the best therapeutic approach and transportation is the most likely complication in preparation of these canals. A crown-down technique, watch-winding motion and a master apical file # 25 are the best choices for preparation of these canals. Any warm obturation technique is preferred over lateral compaction by most respondents. A crown-down technique for root canal preparation and a thermoplastic obturation technique are recommended for canals whose curvature is more than 40°. The prognosis of the treatment of these canals is judged not lower than normal canals. Crown-down technique and thermoplastic obturation are recommended for dilacerated canals.

  19. [Endodontics in motion: new concepts, materials and techniques 3. The role of irrigants during root canal treatment].

    Science.gov (United States)

    van der Sluis, L W M

    2015-10-01

    The aims of root canal irrigation are the chemical dissolution or disruption and the mechanical detachment of pulp tissue, dentin debris and smear layer (instrumentation products), microorganisms (planktonic or biofilm) and their products from the root canal wall, their removal out of the root canal system and their chemical dissolution or disruption. Each of the endodontic irrigation systems has its own irrigant flow characteristics, which should fulfill these aims. Without flow (convection), the irrigant would have to be distributed through diffusion. This process is slow and depends on temperature and concentration gradients. On the other hand, convection is a faster and more efficient transport mechanism. During irrigant flow, frictional forces will occur, for example between the irrigant and the root canal wall (wall shear stress). These frictional forces have a mechanical cleaning effect on the root canal wall. These frictional forces are the result of the flow characteristics related to the different irrigation systems.

  20. Serous otitis media (S.O.M.). A bacteriological study of the ear canal and the middle ear

    NARCIS (Netherlands)

    Cabenda, S. I.; Peerbooms, P. G.; van Asselt, G. J.; Feenstra, L.; van der Baan, S.

    1988-01-01

    A bacteriological study of the middle-ear effusions and the ear canals in children with chronic serous otitis media (S.O.M.) was performed. Sixty-eight children (127 ears) were investigated. From this study it appeared that cleansing of the ear canal with 0.5% chlorhexidine in 70% ethanol for 30 s

  1. Sonochemical and high-speed optical characterization of cavitation generated by an ultrasonically oscillating dental file in root canal models

    NARCIS (Netherlands)

    Macedo, R.G.; Verhaagen, B.; Fernandez Rivas, D.; Gardeniers, J.G.E.; van der Sluis, L.W.M.; Wesselink, P.R.; Versluis, M.

    2014-01-01

    Ultrasonically Activated Irrigation makes use of an ultrasonically oscillating file in order to improve the cleaning of the root canal during a root canal treatment. Cavitation has been associated with these oscillating files, but the nature and characteristics of the cavitating bubbles were not yet

  2. RETRATAMENTO ENDODÔNTICO: ESTUDO COMPARATIVO ENTRE TÉCNICA MANUAL, ULTRA-SOM E CANAL FINDER ENDODONTIC RETREATMENT: COMPARATIVE STUDY BETWEEN MANUAL TECHNIQUE, ULTRASONIC SCALER, AND CANAL FINDER

    Directory of Open Access Journals (Sweden)

    Clovis Monteiro BRAMANTE

    1998-01-01

    Full Text Available Instrumentações manual, ultra-sônica e com Canal Finder foram utilizadas para retratamento de 30 dentes com canais obturados com guta-percha e óxido de zinco e eugenol. Avaliaram-se: 1. tempo gasto para a penetração inicial até o ápice; 2. tempo para completar a limpeza; 3. extrusão de material e 4. limpeza dos canais. O Canal Finder foi a técnica que propiciou melhor limpeza, seguida da manual e da ultra-sônica. A parede palatina do canal foi constantemente mais limpa do que a vestibular. Quanto à extrusão, a técnica de ultra-som foi a que propiciou mais extravasamento de material obturador.Endodontic retreatment of 30 teeth filled with guta percha and zinc oxide-eugenol was carried out using manual instrumentation, ultrasonic scaler, and the Canal Finder System. The following variables were evaluated: time spent to reach the apex; time spent to complete cleaning of the canal; apical extrusion of material; and cleanliness of the canals. Results showed the Canal Finder System as providing the highest level of cleanliness of the canal system; lingual walls were constantly cleaner than buccal walls; ultrasonic technique presented a greater degree of apical extrusion of filling material.

  3. A comparison of three rotary systems and hand instrumentation technique for the elimination of Enterococcus faecalis from the root canal.

    Science.gov (United States)

    Gorduysus, Melahat; Nagas, Emre; Torun, Ozgur Yildirim; Gorduysus, Omer

    2011-12-01

    The aim of this study was to compare the in vitro reduction of a bacterial population in a root canal by mechanical instrumentation using three rotary systems and hand instrumentation technique. The root canals contaminated with a suspension of Enterococcus faecalis were instrumented using ProTaper, K3, HeroShaper and K-file hand instrumentation technique. Later the root canals were sampled. After serial dilutions, samples were incubated in culture media for 24 h. Bacterial colonies were counted and the results were given as number of colony-forming units per millilitre. The results showed that all the canal instrumentation systems reduced the number of bacterial cells in the root canals. Statistically, ProTaper instruments were more effective in reducing the number of bacteria than the other rotary files or hand instruments. © 2010 The Authors. Australian Endodontic Journal © 2010 Australian Society of Endodontology.

  4. 76 FR 34145 - Safety Zone, Barrier Testing Operations, Chicago Sanitary and Ship Canal, Romeoville, IL

    Science.gov (United States)

    2011-06-13

    ...-AA00 Safety Zone, Barrier Testing Operations, Chicago Sanitary and Ship Canal, Romeoville, IL AGENCY.... Construction on Barrier IIB has been completed. Operational and safety testing was conducted in February 2011... dispersal barrier IIA and IIB. This safety zone will be enforced daily from 7 a.m. to 11 a.m. and from 1 p.m...

  5. Relations between well-field pumping and induced canal leakage in east-central Miami-Dade County, Florida, 2010-2011

    Science.gov (United States)

    Nemec, Katherine; Antolino, Dominick J.; Turtora, Michael; Adam Foster,

    2015-08-26

    An extensive canal and water management system exists in south Florida to prevent flooding, replenish groundwater, and impede saltwater intrusion. The unconfined Biscayne aquifer, which underlies southeast Florida and provides water for millions of residents, interacts with the canal system. The Biscayne aquifer is composed of a highly transmissive karst limestone; therefore, canal stage and flow may be affected by production well pumping, especially in locations where production wells and canals are in proximity.

  6. Mental foramen and lingual vascular canals of mandible on MDCT images: anatomical study and review of the literature.

    Science.gov (United States)

    Direk, Filiz; Uysal, Ismihan Ilknur; Kivrak, Ali Sami; Fazliogullari, Zeliha; Unver Dogan, Nadire; Karabulut, Ahmet Kagan

    2018-03-01

    The mental foramen and lingual vascular canals are related to vessels and nerves in the mandibular body. The aim of the present study was to determine the number and location of these structures and to make measurements of them. The archived Multidetector Computed Tomography images of 100 adult (15- to 70-year-old) patients were evaluated retrospectively. The diameters of the mental foramens and their distances from the front, back, upper and lower reference points were measured. The distribution of mental foramens with respect to the teeth was also researched. The presence of lingual vascular canals, and the number of median and lateral canals was determined, and the length of the median lingual vascular canals measured. All measurement parameters were analyzed by gender, side and age group. Eleven patients demonstrated a total of 15 accessory mental foramen. Median lingual vascular canals were observed in 100% of cases, with lateral lingual vascular canals determined in 32%. Significant differences were observed in the results of different gender groups (P mental foramen was determined mostly in males, and unilaterally on the right side; also, the distances of mental foramen, except the distance from the back border of the mandible (P mental foramen, as well as the presence, position and size of lingual vascular canals can be clearly investigated by multidetector computed tomography. A preoperative knowledge of the positions of neurovascular and bone structures is very important for preventing complications that may occur during or after operations.

  7. How a clogged canal effects ecological and human health in a tropical urban wetland ecosystem

    Science.gov (United States)

    The coastal city of San Juan, Puerto Rico is a tropical urban ecosystem interwoven among a series of interconnected bays, lagoons, canals, and mangrove wetlands. As the city has expanded, infilling and urban encroachment on what was previously mangrove wetland and open estuarine ...

  8. Evaluation of Optic Canal and Surrounding Structures Using Cone Beam Computed Tomography: Considerations for Maxillofacial Surgery.

    Science.gov (United States)

    Sinanoglu, Alper; Orhan, Kaan; Kursun, Sebnem; Inceoglu, Beste; Oztas, Bengi

    2016-07-01

    The optic canal connects the anterior cranial fossa and the orbit and maintains the optic nerve and the ophthalmic artery. Within the extent of the surgical approach of the region, risk of iatrogenic injury of the neural and vascular structures increases. The aim of this retrospective morphometric study is to investigate the radiological anatomy of orbita, optic canal, and its surrounding using cone beam computed tomography (CBCT) scans in a group of Turkish population.Cone beam computed tomography images of a total of 182 patients were evaluated by 2 observers. Anatomical parameters regarding optic canal and orbita were measured for all patients from axial, sagittal, and three-dimensional reconstructed images. To assess intraobserver reliability, the Wilcoxon matched-pairs test was used. Pearson χ test and Student t test were performed for statistical analysis of differences, sex, localization, and measurements (P  0.05). The orbita width and height were larger for the males than females (P  0.05). Examination CBCT scans revealed that the shape of the optic canal was 70% funnel and 28% Hourglass shape, 2% amorph type round.These results provide detailed knowledge of the anatomical characteristics in the orbital area which may be of assistance for surgeons preoperatively. Cone beam computed tomography scans can be an alternative modality for multislice computed tomography with submillimeter resolution and lower dose in preoperative imaging of the orbit.

  9. Root Canal Cleaning Efficacy of Rotary and Hand Files Instrumentation in Primary Molars

    Science.gov (United States)

    Nazari Moghaddam, Kiumars; Mehran, Majid; Farajian Zadeh, Hamideh

    2009-01-01

    INTRODUCTION: Pulpectomy of primary teeth is commonly carried out with hand files and broaches; a tricky and time consuming procedure. The purpose of this in vitro study was to compare the cleaning efficacy and time taken for instrumentation of deciduous molars using hand K-files and Flex Master rotary system. MATERIALS AND METHODS: In this study, 68 canals of 23 extracted primary molars with at least two third intact roots and 7-12 mm length were selected. After preparing an access cavity, K-file size #15 was introduced into the root canal and India ink was injected with an insulin syringe. Sixty samples were randomly divided in to experimental groups in group I (n=30), root canals were prepared with hand K-files; in group II (n=30), rotary Flex Master files were used for instrumentation, and in group III 8 remained samples were considered as negative controls. After clearing and root sectioning, the removal of India ink from cervical, middle, and apical thirds was scored. Data was analyzed using student's T-test and Mann-Whitney U test. RESULTS: There was no significant difference between experimental groups cleaning efficacy at the cervical, middle and apical root canal thirds. Only the coronal third scored higher in the hand instrumented group (PInstrumentation with Flex Master rotary files was significantly less time consuming (Protary technique. PMID:23940486

  10. "The Panama Canal Episode: An Encounter with a Question and Answers." Occasional Paper 3.

    Science.gov (United States)

    Seifman, Eli

    This is an account of the experience of a college instructor and a group of prospective social studies teachers as they answer a simple question concerned with direction of travel through the Panama Canal and explore the reactions of students. The situation originates in a class discussion focusing on ways of asking and responding to classroom…

  11. Micro-CT analyses of apical enlargement and molar root canal complexity

    DEFF Research Database (Denmark)

    Markvart, Merete; Darvann, Tron Andre; Larsen, Per

    2012-01-01

    AIM: To compare the effectiveness of two rotary hybrid instrumentation techniques with focus on apical enlargement in molar teeth and to quantify and visualize spatial details of instrumentation efficacy in root canals of different complexity. METHODOLOGY: Maxillary and mandibular molar teeth wer...

  12. OPERATIONAL COSTS OF CANAL COMPANIES AND IRRIGATION DISTRICTS IN THE INTERMOUNTAIN REGION

    OpenAIRE

    Wilkins-Wells, John; Lagae, Hubert J.; Anderson, Raymond L.; Anwer, Muhammad Sarfraz

    1999-01-01

    This study reports on the trends of operational costs of farmer owned and operated irrigation enterprises (irrigation districts and canal companies) in five intermountain states. Administrative costs have risen faster then operation and maintenance costs. While salaries of employees have not risen significantly over time, legal costs have greatly escalated.

  13. Study of Mastoid Canals and Grooves in North Karnataka Human Skulls

    OpenAIRE

    Hadimani, Gavishiddappa Andanappa; Bagoji, Ishwar Basavantappa

    2013-01-01

    Introduction: This study was undertaken to observe the frequency of mastoid canals and grooves in north Karnataka dry human skulls. 100 dry human skulls of unknown age and sex from the department of Anatomy were selected and observed for the present study.

  14. Effect of Lengthy Root Canal Therapy Sessions on Temporomandibular Joint and Masticatory Muscles

    Directory of Open Access Journals (Sweden)

    Safoora Sahebi

    2010-09-01

    Full Text Available Background and aims. Trauma is one of the major factors associated with temporomandibular joint disorders (TMD. These disorders result from macro-trauma or micro-trauma. Macro-trauma might be iatrogenic; for example, from intubation procedures, third molar extraction procedures, and lengthy dental appointments. The aim of this study was to evaluate the effect of lengthy root canal therapy (more than 2 hours on TMJ and its supporting structures. Materials and methods. Eighty patients whose root canal therapy session lasted more than 2 hours were examined for the status of TMJ and masticatory muscles. After one week the second part of the examination was carried out for TMJ problems and pain and tenderness levels of masticatory muscles. Data was analyzed using Wilcoxon statistical test. Results. Women showed more pain compared to men. There was a significant increase in pain in the external acoustic meatus examination one week after root canal therapy. Patients who were treated for their posterior teeth suffered more pain than those who were treated for the anteriors and premolars. Other aspects of the examination were not affected significantly by lengthy root canal therapy. Conclusion. Lengthy dental treatments can harm TMJ and masticatory muscles and wide opening of the mouth during such appointments can worsen the situation. Therefore, it is wise to break the appointment into shorter intervals and let the patients rest during treatment to close their mouth to prevent iatrogenic damage to TMJ.

  15. Effect of Lengthy Root Canal Therapy Sessions on Temporomandibular Joint and Masticatory Muscles

    Science.gov (United States)

    Sahebi, Safoora; Moazami, Fariborz; Afsa, Masoomeh; Nabavi Zade, Mohammad Reza

    2010-01-01

    Background and aims Trauma is one of the major factors associated with temporomandibular joint disorders (TMD). These disorders result from macro-trauma or micro-trauma. Macro-trauma might be iatrogenic; for example, from intuba-tion procedures, third molar extraction procedures, and lengthy dental appointments. The aim of this study was to evaluate the effect of lengthy root canal therapy (more than 2 hours) on TMJ and its supporting structures. Materials and methods Eighty patients whose root canal therapy session lasted more than 2 hours were examined for the status of TMJ and masticatory muscles. After one week the second part of the examination was carried out for TMJ problems and pain and tenderness levels of masticatory muscles. Data was analyzed using Wilcoxon statistical test. Results Women showed more pain compared to men. There was a significant increase in pain in the external acoustic meatus examination one week after root canal therapy. Patients who were treated for their posterior teeth suffered more pain than those who were treated for the anteriors and premolars. Other aspects of the examination were not affected significantly by lengthy root canal therapy. Conclusion Lengthy dental treatments can harm TMJ and masticatory muscles and wide opening of the mouth during such appointments can worsen the situation. Therefore, it is wise to break the appointment into shorter intervals and let the patients rest during treatment to close their mouth to prevent iatrogenic damage to TMJ. PMID:22991607

  16. Reference values for radiological evaluation of cervical vertebral body shape and spinal canal

    Energy Technology Data Exchange (ETDEWEB)

    Remes, V.M. [Hospital for Children and Adolescents, Helsinki University Central Hospital (Finland); Heinaenen, M.T.; Marttinen, E.J. [Department of Radiology, Helsinki University Central Hospital, Helsinki (Finland); Kinnunen, J.S. [Department of Radiology, Helsinki University Central Hospital, HYKS (Finland)

    2000-03-01

    Background. Defining normal values is essential for reliable evaluation of growth disturbances. Previous studies of the cervical spine have mainly focused on the sagittal canal diameter and interpedicular distances. Values for vertebral body height and depth have been published only in adult men and cadavers.Objectives. To define normal values for vertebral body height (H)/vertebral body depth (D) ratio (H/D ratio) and sagittal canal diameter (S)/vertebral body depth ratio (S/D ratio) in C2-7.Materials and methods. Lateral cervical spine radiographs were available from 441 children and 192 adults. Subjects' ages varied from newborn to 39 years. Vertebral body height and depth and sagittal canal diameter were measured and ratios were calculated. This was a cross-sectional and retrospective study.Results. Vertebral bodies grow relatively more in height than in depth, most actively at puberty. At all levels, the H/D ratio remains below 1, indicating that vertebral body depth is greater than height. The SD ratio is quite stable until 7-8 years of age and then it starts to decline slowly.Conclusions. When estimating platyspondyly, the age of the patient must be taken into consideration because vertebral body height is lower in children. Growth of the spinal canal declines after 7-8 years of age. (orig.)

  17. Reference values for radiological evaluation of cervical vertebral body shape and spinal canal

    International Nuclear Information System (INIS)

    Remes, V.M.; Heinaenen, M.T.; Marttinen, E.J.; Kinnunen, J.S.

    2000-01-01

    Background. Defining normal values is essential for reliable evaluation of growth disturbances. Previous studies of the cervical spine have mainly focused on the sagittal canal diameter and interpedicular distances. Values for vertebral body height and depth have been published only in adult men and cadavers.Objectives. To define normal values for vertebral body height (H)/vertebral body depth (D) ratio (H/D ratio) and sagittal canal diameter (S)/vertebral body depth ratio (S/D ratio) in C2-7.Materials and methods. Lateral cervical spine radiographs were available from 441 children and 192 adults. Subjects' ages varied from newborn to 39 years. Vertebral body height and depth and sagittal canal diameter were measured and ratios were calculated. This was a cross-sectional and retrospective study.Results. Vertebral bodies grow relatively more in height than in depth, most actively at puberty. At all levels, the H/D ratio remains below 1, indicating that vertebral body depth is greater than height. The SD ratio is quite stable until 7-8 years of age and then it starts to decline slowly.Conclusions. When estimating platyspondyly, the age of the patient must be taken into consideration because vertebral body height is lower in children. Growth of the spinal canal declines after 7-8 years of age. (orig.)

  18. Cleaning efficacy of reciprocal and rotary systems in the removal of root canal filling material

    Science.gov (United States)

    Koçak, Mustafa Murat; Koçak, Sibel; Türker, Sevinç Aktemur; Sağlam, Baran Can

    2016-01-01

    Aim: The aim of this study was to compare the efficacy of hand file, nickel titanium rotary instrument, and two reciprocating instruments for removing gutta-percha and sealer from the root canals. Materials and Methods: Eighty-eight mandibular premolar teeth were used. The root canals were shaped and filled with gutta-percha and a resin-based sealer. The specimens were divided into four groups according to the technique by which the root filling material was removed: Group 1 — Wave One; Group 2 — Reciproc; Group 3 — ProTaper; and Group 4 — Gates-Glidden burs and stainless steel hand file. Then teeth were split longitudinally and photographed. The images were transferred to a computer. The ratio of remaining filling material to the root canal periphery was calculated with the aid of ImageJ software. Statistical analysis was performed using Kruskal–Wallis and Mann–Whitney tests. Results: A significant difference was found among all groups (P hand file. Conclusion: The reciprocating files were found to be significantly more effective in removing the filling material from the canal walls compared to the rotational file and hand file. PMID:27099429

  19. Impact of lining material on chemical and microbial irrigation water quality of Nubaria canal, Egypt

    Directory of Open Access Journals (Sweden)

    Ahmed Mohamed Azzam

    2016-02-01

    Full Text Available Objective: To assess the effect of lining material (cement of Nubaria canal (Beheira Governorate, Egypt on its water quality. Methods: Trace metal ions (Fe, Zn, Cu, Pb, and Cd and bacterial indictors for water samples collected from two types of stations (lined and unlined during successive four seasons were analyzed. The effect of lining on bacterial indicators; total viable bacterial count at 22 and 37 °C, total coliform, fecal coliform and fecal streptococci and presence of some bacterial species were studied. Results: Bacterial indicators and trace metals showed seasonal variations, where the highest values were recorded during summer. A significant reduction for Cu (P < 0.05, Zn (P < 0.01 and Cd (P < 0.001 was recorded in lined stations compared to those of unlined ones. Bacterial indicators recorded the lowest counts in lined stations during all seasons, while there was a significant reduction (P < 0.05 between total coliform values (1.70 ± 0.50 in lined stations and unlined ones (3.57 ± 1.01 during summer. Escherichia coli bacteria were predominant in water samples of Nubaria canal, where it recorded 34.4% of bacterial isolates. Conclusions: Lined material plays a role for reducing the bacterial growth and metals concentration, therefore the lining of canal helps in preventing the discharge of sewage pollution into canal.

  20. Root Anatomy and Root Canal Configuration of Human Permanent Mandibular Premolars: A Systematic Review

    Directory of Open Access Journals (Sweden)

    Jojo Kottoor

    2013-01-01

    Full Text Available Introduction. Mandibular premolars have been reported with complex anatomical aberrations, making them one of the most difficult teeth to manage endodontically. Methodology. An exhaustive search was undertaken to identify associated anatomic studies of mandibular premolars through MEDLINE/PubMed database using keywords, and a systematic review of the relevant articles was performed. Chi-square test with Yates correction was performed to assess the statistical significance of any anatomic variations between ethnicities and within populations of the same ethnicity. Documented case reports of variations in mandibular premolar anatomy were also identified and reviewed. Results. Thirty-six anatomic studies were analyzed which included 12,752 first premolars and nineteen studies assessing 6646 second premolars. A significant variation in the number of roots, root canals, and apical foramen was observed between Caucasian, Indian, Mongoloid, and Middle Eastern ethnicities.The most common anatomic variation was C-shaped canals in mandibular first premolars with highest incidence in Mongoloid populations (upto 24% while dens invaginatus was the most common developmental anomaly. Conclusions. A systematic review of mandibular premolars based on ethnicity and geographic clusters offered enhanced analysis of the prevalence of number of roots and canals, their canal configuration, and other related anatomy.

  1. CT study of the performance of reciprocating and oscillatory motions in flattened root canal areas

    Directory of Open Access Journals (Sweden)

    Cacio MOURA-NETTO

    2015-01-01

    Full Text Available Root canal preparation is an important step in endodontic treatment. The anatomical complexity of the middle third of the root compromises the effective cleaning of this area. Thus, advances have been made in instrumentation techniques and instruments for this purpose. The aim of this study was to evaluate the effects of three different instrumentation systems on the enlargement of the middle thirds of root canals in mandibular incisors. The preparation methods used were the reciprocating systems Reciproc (Group I and WaveOne (Group II and the oscillatory system Tilos (Group III. Comparisons were made by three-dimensional image reconstruction with cone-beam computed tomography before and after instrumentation. Changes in area, perimeter, centering ability, and pattern of preparation were analyzed. The results were subjected to ANOVA complemented by the Tukey’s test. Changes in area, perimeter, and tendency of transportation showed similar results among groups. The transportation index of the Tilos system was significantly lower than that of the other groups. Qualitative analysis of the preparation pattern showed that the Tilos system had a more uniform preparation, although Reciproc and WaveOne preparations appeared more rounded, incompatible with the original canal anatomy. There was similarity in the systems’ performance on flattened areas, although the Tilos system presented a better pattern of root canal preparation and a lower index of transportation.

  2. Child Development in the Context of Adversity: Experiential Canalization of Brain and Behavior

    Science.gov (United States)

    Blair, Clancy; Raver, C. Cybele

    2012-01-01

    The authors examine the effects of poverty-related adversity on child development, drawing upon psychobiological principles of experiential canalization and the biological embedding of experience. They integrate findings from research on stress physiology, neurocognitive function, and self-regulation to consider adaptive processes in response to…

  3. CT study of the performance of reciprocating and oscillatory motions in flattened root canal areas

    International Nuclear Information System (INIS)

    Moura-Netto, Cacio; Palo, Renato Miotto; Pinto, Larissa Fernanda; Daltoe, Gisele; Mello-Moura, Anna Carolina Volpi

    2015-01-01

    Abstract: Root canal preparation is an important step in endodontic treatment. The anatomical complexity of the middle third of the root compromises the effective cleaning of this area. Thus, advances have been made in instrumentation techniques and instruments for this purpose. The aim of this study was to evaluate the effects of three different instrumentation systems on the enlargement of the middle thirds of root canals in mandibular incisors. The preparation methods used were the reciprocating systems Reciproc (Group I) and WaveOne (Group II) and the oscillatory system Tilos (Group III). Comparisons were made by three-dimensional image reconstruction with cone-beam computed tomography before and after instrumentation. Changes in area, perimeter, centering ability, and pattern of preparation were analyzed. The results were subjected to ANOVA complemented by the Tukey’s test. Changes in area, perimeter, and tendency of transportation showed similar results among groups. The transportation index of the Tilos system was significantly lower than that of the other groups. Qualitative analysis of the preparation pattern showed that the Tilos system had a more uniform preparation, although Reciproc and WaveOne preparations appeared more rounded, incompatible with the original canal anatomy. There was similarity in the systems’ performance on flattened areas, although the Tilos system presented a better pattern of root canal preparation and a lower index of transportation. (author)

  4. Wnt signaling regulates atrioventricular canal formation upstream of BMP and Tbx2

    NARCIS (Netherlands)

    Verhoeven, Manon C.; Haase, Christa; Christoffels, Vincent M.; Weidinger, Gilbert; Bakkers, Jeroen

    2011-01-01

    In the developing heart, the atrioventricular canal (AVC) is essential for separation and alignment of the cardiac chambers, for valve formation, and serves to delay the electrical impulse from the atria to the ventricles. Defects in various aspects of its formation are the most common form of

  5. CT study of the performance of reciprocating and oscillatory motions in flattened root canal areas

    Energy Technology Data Exchange (ETDEWEB)

    Moura-Netto, Cacio, E-mail: caciomn@usp.br [Universidade Cruzeiro do Sul (UNICSUL), Sao Paulo, SP (Brazil). Fac. de Odontologia; Palo, Renato Miotto [Universidade Estadual Paulista Julio de Mesquita Filho (ICT/UNESP), Sao Jose dos Campos, SP (Brazil). Instituto de Ciencia e Tecnologia; Pinto, Larissa Fernanda; Daltoe, Gisele; Mello-Moura, Anna Carolina Volpi [Universidade Ibirapuera (UNIB), Sao Paulo, SP (Brazil). Fac. de Odontologia

    2015-03-01

    Abstract: Root canal preparation is an important step in endodontic treatment. The anatomical complexity of the middle third of the root compromises the effective cleaning of this area. Thus, advances have been made in instrumentation techniques and instruments for this purpose. The aim of this study was to evaluate the effects of three different instrumentation systems on the enlargement of the middle thirds of root canals in mandibular incisors. The preparation methods used were the reciprocating systems Reciproc (Group I) and WaveOne (Group II) and the oscillatory system Tilos (Group III). Comparisons were made by three-dimensional image reconstruction with cone-beam computed tomography before and after instrumentation. Changes in area, perimeter, centering ability, and pattern of preparation were analyzed. The results were subjected to ANOVA complemented by the Tukey’s test. Changes in area, perimeter, and tendency of transportation showed similar results among groups. The transportation index of the Tilos system was significantly lower than that of the other groups. Qualitative analysis of the preparation pattern showed that the Tilos system had a more uniform preparation, although Reciproc and WaveOne preparations appeared more rounded, incompatible with the original canal anatomy. There was similarity in the systems’ performance on flattened areas, although the Tilos system presented a better pattern of root canal preparation and a lower index of transportation. (author)

  6. Aspects of the anatomy and histology of the alimentary canal of the ...

    African Journals Online (AJOL)

    Aspects of the anatomy and histology of the alimentary canal of Thryonomys swinderianus were studied to gain a better understanding of this animal's ability to digest large quantities of fibre. Morphometric measurements of the gut regions were taken with the aid of light, transmission and scanning electron microscopy.

  7. Association between type 1 diabetes mellitus and deposits in the semicircular canals.

    Science.gov (United States)

    Yoda, Shigetoshi; Cureoglu, Sebahattin; Yildirim-Baylan, Muzeyyen; Morita, Norimasa; Fukushima, Hisaki; Harada, Tamotsu; Paparella, Michael M

    2011-09-01

    To compare the prevalence of cupular and free-floating deposits in the semicircular canals between temporal bones of type 1 diabetes mellitus patients and normal controls. Case-control histopathologic human temporal bone study. Otopathology laboratory in a tertiary academic medical center. Twenty-eight temporal bones from 14 patients with type 1 diabetes mellitus and 56 normal temporal bones from 28 age-matched individuals were histopathologically examined. The cupula and lumina of the semicircular canals were examined for evidence of deposits. The prevalence of cupular and free-floating deposits in the lateral and posterior semicircular canals was significantly higher in type 1 diabetes mellitus patients compared with normal temporal bones (lateral, cupular deposits, odds ratio [OR], 5.47; 95% confidence interval [CI], 1.43 to 21.02; free-floating deposits, OR, 8.25; 95% CI, 2.42 to 27.85; posterior, cupular deposits, OR, 41.73; 95% CI, 5.96 to 275.50; free-floating deposits, OR, 7.44; 95% CI, 1.91 to 28.53). The prevalence of these deposits was associated with the duration of disease rather than with aging. The findings suggest that type 1 diabetes mellitus is associated with cupular and free-floating deposits in the semicircular canals. The patients with type 1 diabetes mellitus with a longer duration of disease have an increased probability of suffering from benign paroxysmal positional vertigo.

  8. The visibility of mandibular canal on orthoradial and oblique CBCT slices at molar implant sites

    International Nuclear Information System (INIS)

    Alkhader, Mustafa; Jarab, Fadi; Shaweesh, Ashraf; Hudieb, Malik

    2016-01-01

    The aim of the present study was to compare visibility of the mandibular canal on cone beam computed tomography (CBCT)-based orthoradial and oblique slices at molar implant sites. CBCT images for 132 mandibular molar implant sites were selected for the study. After generating orthoradial and oblique slices, two observers evaluated the visibility of the mandibular canal using three-point scoring scale (1-3, good to excellent). Wilcoxon signed-rank test compared the visibility scores of the two slices. Both orthoradial and oblique slices obtained from CBCT had only very good to excellent mandibular canal visibility scores. At 114 mandibular molar implant sites, the visibility score was equal on both orthoradial and oblique slices. Although the visibility score was higher on orthoradial slices for 12 implant sites, the visibility score was higher for six implant sites on oblique slices and the difference was not significant. Therefore, the visibility of the mandibular canal was excellent and comparable on most of orthoradial and oblique slices obtained from CBCT images

  9. Turning semicircular canal function on its head: dinosaurs and a novel vestibular analysis.

    Science.gov (United States)

    Georgi, Justin A; Sipla, Justin S; Forster, Catherine A

    2013-01-01

    Previous investigations have correlated vestibular function to locomotion in vertebrates by scaling semicircular duct radius of curvature to body mass. However, this method fails to discriminate bipedal from quadrupedal non-avian dinosaurs. Because they exhibit a broad range of relative head sizes, we use dinosaurs to test the hypothesis that semicircular ducts scale more closely with head size. Comparing the area enclosed by each semicircular canal to estimated body mass and to two different measures of head size, skull length and estimated head mass, reveals significant patterns that corroborate a connection between physical parameters of the head and semicircular canal morphology. Head mass more strongly correlates with anterior semicircular canal size than does body mass and statistically separates bipedal from quadrupedal taxa, with bipeds exhibiting relatively larger canals. This morphologic dichotomy likely reflects adaptations of the vestibular system to stability demands associated with terrestrial locomotion on two, versus four, feet. This new method has implications for reinterpreting previous studies and informing future studies on the connection between locomotion type and vestibular function.

  10. Preparation of severely curved simulated root canals using engine-driven rotary and conventional hand instruments.

    Science.gov (United States)

    Szep, S; Gerhardt, T; Leitzbach, C; Lüder, W; Heidemann, D

    2001-03-01

    This in vitro study evaluated the efficacy and safety of six different nickel-titanium engine-driven instruments used with a torque-controlled engine device and nickel-titanium hand and stainless steel hand instruments in preparation of curved canals. A total of 80 curved (36 degrees) simulated root canals were prepared. Images before and after were superimposed, and instrumentation areas were observed. Time of instrumentation, instrument failure, change in working length and weight loss were also recorded. Results show that stainless steel hand instruments cause significantly less transportation towards the inner wall of the canal than do nickel-titanium hand instruments. No instrument fracture occurred with hand instruments, but 30-60% breakage of instruments was recorded during instrumentation with the engine-driven devices. The working length was maintained by all types of instruments. Newly developed nickel-titanium rotary files were not able to prevent straightening of the severely curved canals when a torque-controlled engine-driven device was used.

  11. Numerical modeling of the 1964 Alaska tsunami in western Passage Canal and Whittier, Alaska

    Directory of Open Access Journals (Sweden)

    D. J. Nicolsky

    2010-12-01

    Full Text Available A numerical model of the wave dynamics in Passage Canal, Alaska during the Mw 9.2 megathrust earthquake is presented. During the earthquake, several types of waves were identified at the city of Whittier, located at the head of Passage Canal. The first wave is thought to have been a seiche, while the other two waves were probably triggered by submarine landslides. We model the seiche wave, landslide-generated tsunami, and tectonic tsunami in Passage Canal and compute inundation by each type of wave during the 1964 event. Modeled results are compared with eyewitness reports and an observed inundation line. Results of the numerical experiments let us identify where the submarine landslides might have occurred during the 1964 event. We identify regions at the head and along the northern shore of Passage Canal, where landslides triggered a wave that caused most of the damage in Whittier. An explanation of the fact that the 1964 tectonic tsunami in Whittier was unnoticed is presented as well. The simulated inundation by the seiche, landslide-generated tsunami, and tectonic tsunami can help to mitigate tsunami hazards and prepare Whittier for a potential tsunami.

  12. Turning semicircular canal function on its head: dinosaurs and a novel vestibular analysis.

    Directory of Open Access Journals (Sweden)

    Justin A Georgi

    Full Text Available Previous investigations have correlated vestibular function to locomotion in vertebrates by scaling semicircular duct radius of curvature to body mass. However, this method fails to discriminate bipedal from quadrupedal non-avian dinosaurs. Because they exhibit a broad range of relative head sizes, we use dinosaurs to test the hypothesis that semicircular ducts scale more closely with head size. Comparing the area enclosed by each semicircular canal to estimated body mass and to two different measures of head size, skull length and estimated head mass, reveals significant patterns that corroborate a connection between physical parameters of the head and semicircular canal morphology. Head mass more strongly correlates with anterior semicircular canal size than does body mass and statistically separates bipedal from quadrupedal taxa, with bipeds exhibiting relatively larger canals. This morphologic dichotomy likely reflects adaptations of the vestibular system to stability demands associated with terrestrial locomotion on two, versus four, feet. This new method has implications for reinterpreting previous studies and informing future studies on the connection between locomotion type and vestibular function.

  13. Influence of the Houma Navigation Canal on Salinity Patterns and Landscape Configuration in Coastal Louisiana

    Science.gov (United States)

    Steyer, Gregory D.; Sasser, Charles; Evers, Elaine; Swenson, Erick; Suir, Glenn; Sapkota, Sijan

    2008-01-01

    Coastal Louisiana is a dynamic and ever changing landscape. From 1956 to 2004, over 297,000 ha of Louisiana's coastal wetlands were lost because of the effects of natural and human-induced activities. Studies show that, in 2005, Hurricanes Katrina and Rita transformed over 56,200 ha of wetlands to open water in various parts of coastal Louisiana. Besides the catastrophic hurricanes, factors such as subsidence, sea-level rise, freshwater and sediment deprivation, saltwater intrusion, the dredging of oil and gas canals, navigation canals, shoreline erosion, and herbivory are all contributors to wetland loss in Louisiana. Various scientific literatures have well described the direct impacts associated with an immediate physical conversion of habitat in coastal Louisiana; however, the indirect impacts that are subtle and operate over longer time horizons (such as salinity intrusion) have been difficult to discern. In this report, long-term influences on salinity patterns and landscape configuration are evaluated for pre- and postconstruction periods of the Houma Navigation Canal (HNC), which is located in the coastal region of southeastern Louisiana. Analysis of daily and hourly salinity data from long-term data collection stations within the areas surrounding the HNC indicated that there were no obvious patterns in increasing salinity levels following the completion of the canal, except for the immediate increase in salinity spikes that occurred toward the completion of its construction in 1961. Increases in salinity spikes were also observed during a severe drought in 1999-2000. Data from Bayou Grand Caillou at Dulac, however, show a longer term trend of increasing salinity levels, which is similar to the pattern observed at the Houma Water Treatment Plant. A potential explanation for these patterns is based on the dredging history of the HNC, where dates of maintenance dredging correspond fairly closely to the salinity peaks in Bayou Grand Caillou and the canal. It

  14. Comparison of Endoflas and Zinc oxide Eugenol as root canal filling materials in primary dentition

    Directory of Open Access Journals (Sweden)

    Nivedita Rewal

    2014-01-01

    Full Text Available Background: Zinc oxide eugenol has long been the material of choice of pediatric dentists worldwide, although it fails to meet the ideal requirements of root canal filling material for primary teeth. Endoflas, a mixture of zinc oxide eugenol, calcium hydroxide, and iodoform, can be considered to be an effective root canal filling material in primary teeth as compared with zinc oxide eugenol. This study was carried out to compare zinc oxide eugenol with endoflas for pulpectomy in primary dentition. Aim: The objective of the study was to compare clinically and radiographically success rates of zinc oxide eugenol with endoflas for the root canal filling of primary teeth at 3, 6, and 9 months. Design: Fifty primary molars were included in the study with 26 teeth in Group I (Endoflas and 24 in Group II (zinc oxide eugenol. A single visit pulpectomy was carried out. Results: The overall success rate of zinc oxide eugenol was 83% whereas 100% success was found in the case of endoflas. The obtained results were compiled and subjected to statistical analysis using the chi-square test. The difference in the success rate between the two was statistically significant (P < 0.05. Conclusion: Endoflas has shown to have better results than zinc oxide eugenol. It should therefore be the material of choice for root canal treatment in deciduous dentition.

  15. [The features of high and low-frequency function of horizontal, semicircular canal in Meniere's disease].

    Science.gov (United States)

    Chen, Ying; Zhao, Zhongxin; Zhuang, Jianhua; Xie, Xuewei; Jin, Zhe; Li, Fei

    2015-05-01

    To analyze the feature of horizontal semicircular canal function at high and low-frequencies in Meniere's disease. Thirty patients suffering from unilateral Meniere's disease were included in the research from 2013 June to 2014 June. Caloric test and video head impulse test were performed to evaluate the high low-frequency function of horizontal semicircular canal. these patients were devided by the severity of unilateral weakness in caloric test. The gain value in video head impulse test, which reflects the high-frequency function of semicircular canal, were not different between the normal and mild abnormal group (P > 0.05), but were obviously different between the normal and mild-severe abnormal group, slight abnormal and mild-severe abnormal group (P frequency function of both side, has no difference between three groups (P > 0.05). A part of Meniere's disease may have normal high, low-frequency function of horizontal semicircular canal. As patient suffering slight injury of low-frequency function, the high-frequency function keeps normal. As the injury of low-frequency function become mildly to severely, the damage of high-frequency function appears, but the symmetry still keeps balance.

  16. A comparison of patterns of disease extension in keratosis obturans and external auditory canal cholesteatoma.

    Science.gov (United States)

    Shinnabe, Akihiro; Hara, Mariko; Hasegawa, Masayo; Matsuzawa, Shingo; Kanazawa, Hiromi; Yoshida, Naohiro; Iino, Yukiko

    2013-01-01

    To investigate the different pathways of progression to the middle ear in keratosis obturans (KO) and external auditory canal cholesteatoma (EACC). Retrospective case review. Referral hospital otolaryngology department. Patients with KO or EACC and middle ear disease who underwent surgical management were included. Four ears of 4 patients (mean age, 41.25 yr) were the KO group, and 5 ears of 4 patients (mean age, 49.5 yr) were the EACC group. Intraoperative findings of the middle ear cavity were investigated in KO and EACC groups. In the KO group, 3 patients had a perforated tympanic membrane and cholesteatoma in the tympanic cavity. The other patient had preoperative right facial palsy. Removal of the keratin plug revealed an adherent tympanic membrane. In intraoperative findings, the tympanic segment of the fallopian canal was found to be eroded because of inflammation. No case initially progressed to the mastoid cavity. Four patients had external auditory canal cholesteatoma with middle ear disease. In EACC group, all patients had initial progression to the mastoid cavity. KO tends to progress initially to the tympanic cavity via a diseased tympanic membrane. EACC tends to progress to the mastoid cavity via destruction of the posterior bony canal. This is the first report to investigate differences in pathway of progression to the middle ear cavity in these 2 diseases.

  17. Neurovascular Content of the Mandibular Canal and Its Clinical Relevance: A Literature Review of the Related Anatomical and Radiological Studies

    Directory of Open Access Journals (Sweden)

    Eliades Apostolos N.

    2014-11-01

    Full Text Available In literature, anatomical variations of the inferior alveolar nerve branches (infratemporal, extraosseous and intraosseous are reported and their importance in clinical practice is discussed too. The spatial vessels’ position in relationship with the nerve in the mandibular canal was explored, which is of clinical significance in impacted third molar and implant surgery. It is believed that the neurovascular content of the main mandibular canal follows any variations of the mandibular canal i.e. bifid mandibular, retromolar and accessory mental canals. Retrospective studies and case reports reported the presence of multiple foramina on the medial surface of the ramus, near the main mandibular foramen. In some cases, one supplementary mandibular foramen was found to be connected with the lower third molar, which is called “temporal crest canal”. Others found an accessory mandibular foramen that led into a second mandibular canal which joined the main mandibular canal (double anteriorly. The bony canals contained a terminal branch of the anterior trunk of the mandibular nerve or a branch of inferior alveolar nerve before it entered the mandibular foramen.

  18. Risks and consequences of a hypothetical radiological accident on nuclear powered submarine traversing Suez canal

    International Nuclear Information System (INIS)

    Salama, Mohamed

    2008-01-01

    Full text: Egypt has unique problem in Suez Canal, although there are, a number of radioactive Cargos traveling through the Canal which includes new and spent reactor fuel and about 100 metric tons of uranium hexafluoride each year, under the regulatory control of the Egyptian Atomic Energy Authority, there is, still a major problem concerning the passage of a number of nuclear powered vessels and submarines passing through the canal several times each year. The passage of these vessels and submarines has a political situation and not under the regulatory control of the Egyptian regulatory body. In spite of all precautions that are taken, in the nuclear powered vessels and submarines from the point of view of the rugged design of the reactor plant, multiple safety systems and operation with exceptional consideration for safety. Although of all of these a potential for a serious accident may does arise, even though, its probability is minimal. The Government of Egypt has established a national radiological emergency plan in order to cope with any radiological accidents, which may arise inside the country. Suez Canal lies in the north east of Egypt, and passes through a zone of considerable business, agriculture and industrial activities. The zone consists of three populated provinces, Port Said, Ismailia and Suez. According to Suez Canal authority regulations it is not allowed for these vessels and submarines to be landed in port. The motivation of the present paper was undertaken to discuss a hypothetical nuclear reactor accident aboard a nuclear powered submarine occurred during its passage in the Suez Canal. Such an accident will produce a radioactive cloud containing a number of radioactive materials. In such type of accidents contamination and causality zones, could extend to several kilometers. The different phases of the accident are going to be discussed and analyzed. The emergency actions taken during the accident phases are going to be presented. The

  19. 75 FR 80526 - Chesapeake and Ohio Canal National Historical Park Advisory Commission; Notice of Public Meeting

    Science.gov (United States)

    2010-12-22

    .... Charles D. McElrath Ms. Patricia Schooley Mr. Jack Reeder Ms. Merrily Pierce Topics that will be presented... of the Chesapeake and Ohio Canal National Historical Park Advisory Commission will be held at 9:30 a... personal identifying information from public review, we cannot guarantee that we will be able to do so. The...

  20. Comparison of different retreatment techniques and root canal sealers: a scanning electron microscopic study

    Directory of Open Access Journals (Sweden)

    Neslihan Simsek

    2014-05-01

    Full Text Available The aim of this study was to evaluate the effectiveness of two retreatment techniques, in terms of the operating time and scanning electron microscopy (SEM results, in removing three different root canal sealers from root canals that were previously filled with gutta-percha. Sixty extracted single-rooted human premolars were divided into three groups and filled with iRoot SP, MM Seal, and AH Plus sealers, along with gutta-percha, through a lateral compaction technique. Root canal fillings of the samples were removed by ESI ultrasonic tips or R-Endo files. The time to reach the working length was recorded. Longitudinally sectioned samples were examined under SEM magnification. Each picture was evaluated in terms of the residual debris. Data were statistically analyzed with the Kruskall-Wallis test. No statistically significant differences were found in terms of operating time (p>0.05. Significant differences in the number of debris-free dentinal tubules were found among the root canal thirds, but this finding was not influenced by the experimental group (p < 0.05. Resin sealer tags were observed inside the dentinal tubules in the MM Seal group. Under the conditions of this study, it may be established that there was no difference among the sealers and retreatment techniques.

  1. Opinion Polls and the Panama Canal Treaties of 1977: A Critical Analysis.

    Science.gov (United States)

    Smith, Ted J., III; Hogan, J. Michael

    Noting that 1977 public opinion polls concerning the new Panama Canal treaties were interpreted as showing increased support for the treaties, this paper contends that this interpretation was erroneous and that the major outcome of the extensive polling was misleading data. The paper is divided into three major analytical sections. The first…

  2. Micro‐CT analyses of apical enlargement and molar root canal complexity

    DEFF Research Database (Denmark)

    Markvart, M.; Darvann, Tron Andre; Larsen, P.

    2012-01-01

    Markvart M, Darvann TA, Larsen P, Dalstra M, Kreiborg S, Bjørndal L. Micro‐CT analyses of apical enlargement and molar root canal complexity. International Endodontic Journal, 45, 273–281, 2012. Aim To compare the effectiveness of two rotary hybrid instrumentation techniques with focus on apical...

  3. Predictive control of irrigation canals – robust design and real-time implementation

    NARCIS (Netherlands)

    Aguilar, José V.; Langarita, Pedro; Rodellar, José; Linares, Lorenzo; Horváth, K.

    2016-01-01

    Predictive control is one of the most commonly used control methods in a variety of application areas, including hydraulic processes such as water distribution canals for irrigation. This article presents the design and application of predictive control for the water discharge entering into an

  4. On the waterfront : water distribution, technology and agrarian change in a South Indian canal irrigation system

    NARCIS (Netherlands)

    Mollinga, P.P.

    1998-01-01

    This book discusses water distribution in the Tungabhadra Left Bank Canal irrigation system in Raichur district, Karnataka, India. The system is located in interior South India, where rainfall is limited (approximately 600 mm annually) and extremely variable. The region suffered from failed

  5. 33 CFR 207.20 - Cape Cod Canal, Mass.; use, administration, and navigation.

    Science.gov (United States)

    2010-07-01

    ... basis. A patrol vessel is manned and operational 24-hours a day. (c) Communications. There is a marine... section. Low powered vessels will be required to await slack water or favorable current for canal transit... Fair Tide—30 Minutes Slack Tide—45 Minutes The minimun running time between the Administration Office...

  6. Aetiology, incidence and morphology of the C-shaped root canal system and its impact on clinical endodontics

    Science.gov (United States)

    Kato, A; Ziegler, A; Higuchi, N; Nakata, K; Nakamura, H; Ohno, N

    2014-01-01

    The C-shaped root canal constitutes an unusual root morphology that can be found primarily in mandibular second permanent molars. Due to the complexity of their structure, C-shaped root canal systems may complicate endodontic interventions. A thorough understanding of root canal morphology is therefore imperative for proper diagnosis and successful treatment. This review aims to summarize current knowledge regarding C-shaped roots and root canals, from basic morphology to advanced endodontic procedures. To this end, a systematic search was conducted using the MEDLINE, BIOSIS, Cochrane Library, EMBASE, Google Scholar, Web of Science, PLoS and BioMed Central databases, and many rarely cited articles were included. Furthermore, four interactive 3D models of extracted teeth are introduced that will allow for a better understanding of the complex C-shaped root canal morphology. In addition, the present publication includes an embedded best-practice video showing an exemplary root canal procedure on a tooth with a pronounced C-shaped root canal. The survey of this unusual structure concludes with a number of suggestions concerning future research efforts. PMID:24483229

  7. Premolar root and canal variation in extant non-human hominoidea.

    Science.gov (United States)

    Moore, N Collin; Hublin, Jean-Jacques; Skinner, Matthew M

    2015-08-11

    The premolar sub-cervical region in four non-human extant ape genera are examined to: 1) define a classification scheme for the premolar root system in order to rigorously characterize, quantify and document variation in root and canal, form, number and configuration; 2) compare this variation within and between genera; and 3) test the hypotheses that sex and size (i.e., the "size/number continuum," Shields, ) of the premolar are determinants of root/canal form and/or number. Microtomography and 3D visualization software are utilized to examine a large sample of Hylobates, Pan, Gorilla, and Pongo (n = 951 teeth). Each premolar root system is examined to ascertain the expected level of variability for each taxon. Cervical surface area (mm 2 ) serves as a metric proxy for tooth size. A Chi-square test of independence is used to assess for variability differences between and within each taxon, and Mann-Whitney U tests are employed to assess the predicted relationship between tooth size and variation within each taxon. Our findings indicate that root and canal configurations, non-metric root traits and tooth size can distinguish between extant ape genera. Within the four ape taxa, premolar size variation is generally, but not always, correlated with canal/root number. Our results indicate that males and females within genera differ in tooth size but not in canal/root form and number. We report previously undocumented variation in the study taxa. Our results are discussed within the context of Miocene Apes as well as the developmental and systematic implications. Am J Phys Anthropol, 2015. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

  8. Visual and quantitative assessment of lateral lumbar spinal canal stenosis with magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Sipola, Petri; Vanninen, Ritva; Manninen, Hannu (Univ. of Eastern Finland, Faculty of Health Sciences, School of Medicine, Inst. of Clinical Medicine, Dept. of Clinical Radiology, Kuopio (Finland); Kuopio Univ. Hospital, Clinical Imaging Centre, Dept. of Clinical Radiology, Kuopio (Finland)), email: petri.sipola@kuh.fi; Leinonen, Ville (Kuopio Univ. Hospital, Dept. of Neurosurgery, Kuopio (Finland)); Niemelaeinen, Riikka (Kuopio Univ. Hospital, Clinical Imaging Centre, Dept. of Clinical Radiology, Kuopio (Finland); Faculty of Rehabilitation Medicine, Univ. of Alberta, Edmonton, Alberta (Canada)); Aalto, Timo (Kyyhkylae Rehabilitation Center and Hospital, Mikkeli (Finland)); Airaksinen, Olavi (Kuopio Univ. Hospital, Dept. of Physical and Rehabilitation Medicine and Univ. of Eastern Finland, Faculty of Health Sciences, School of Medicine, Inst. of Clinical Medicine, Kuopio (Finland)); Battie, Michele C. (Faculty of Rehabilitation Medicine, Univ. of Alberta, Edmonton, Alberta (Canada))

    2011-11-15

    Background. Lateral lumbar spinal canal stenosis is a common etiology of lumbar radicular symptoms. Quantitative measurements have commonly demonstrated better repeatability than visual assessments. We are not aware of any studies examining the repeatability of quantitative assessment of the lateral canal. Purpose. To evaluate the repeatability of visual assessments and newly developed quantitative measurements of lateral lumbar spinal canal stenosis using magnetic resonance imaging (MRI). Material and Methods. Twenty-eight patients with lateral lumbar spinal canal stenosis or prior spinal surgery with recurrent symptoms were imaged with MRI. A radiologist, a neurosurgeon and a spine research trainee graded visually and quantitatively subarticular (n = 188) and foraminal zones (n = 260) of the lateral spinal canal. Quantitative measurements included the minimal subarticular width and the cross-sectional area of the foramen. Results. The repeatability of visual assessment at the subarticular zone and foraminal zones between raters varied from 0.45-0.59 and 0.42-0.53, respectively. Similarly, the intraclass correlation coefficients for the quantitative measurements varied from 0.67-0.71 and 0.66-0.76, respectively. The intra-rater repeatability for the visual assessments of the subarticular and foraminal zones was 0.70 and 0.62, respectively, while the corresponding intraclass correlation coefficients for quantitative measurements were 0.83 and 0.81, respectively. Conclusion. Inter-rater repeatability of visual assessments of lateral stenosis is moderate, whereas quantitative measurements of both subarticular width and the cross-sectional area of the foramen have substantial reproducibility and may be particularly useful for longitudinal studies and research purposes. The clinical value of these parameters requires further study

  9. Visual and quantitative assessment of lateral lumbar spinal canal stenosis with magnetic resonance imaging

    International Nuclear Information System (INIS)

    Sipola, Petri; Vanninen, Ritva; Manninen, Hannu; Leinonen, Ville; Niemelaeinen, Riikka; Aalto, Timo; Airaksinen, Olavi; Battie, Michele C.

    2011-01-01

    Background. Lateral lumbar spinal canal stenosis is a common etiology of lumbar radicular symptoms. Quantitative measurements have commonly demonstrated better repeatability than visual assessments. We are not aware of any studies examining the repeatability of quantitative assessment of the lateral canal. Purpose. To evaluate the repeatability of visual assessments and newly developed quantitative measurements of lateral lumbar spinal canal stenosis using magnetic resonance imaging (MRI). Material and Methods. Twenty-eight patients with lateral lumbar spinal canal stenosis or prior spinal surgery with recurrent symptoms were imaged with MRI. A radiologist, a neurosurgeon and a spine research trainee graded visually and quantitatively subarticular (n = 188) and foraminal zones (n = 260) of the lateral spinal canal. Quantitative measurements included the minimal subarticular width and the cross-sectional area of the foramen. Results. The repeatability of visual assessment at the subarticular zone and foraminal zones between raters varied from 0.45-0.59 and 0.42-0.53, respectively. Similarly, the intraclass correlation coefficients for the quantitative measurements varied from 0.67-0.71 and 0.66-0.76, respectively. The intra-rater repeatability for the visual assessments of the subarticular and foraminal zones was 0.70 and 0.62, respectively, while the corresponding intraclass correlation coefficients for quantitative measurements were 0.83 and 0.81, respectively. Conclusion. Inter-rater repeatability of visual assessments of lateral stenosis is moderate, whereas quantitative measurements of both subarticular width and the cross-sectional area of the foramen have substantial reproducibility and may be particularly useful for longitudinal studies and research purposes. The clinical value of these parameters requires further study

  10. Cleaning and decompression of inferior alveolar canal to treat dysesthesia and paresthesia following endodontic treatment of a third molar

    Directory of Open Access Journals (Sweden)

    Rudy Scala

    2014-01-01

    Full Text Available Endodontic overfilling involving the mandibular canal may cause an injury of the inferior alveolar nerve (IAN. We report a case of disabling dysesthesia and paresthesia of a 70-year-old man after endodontic treatment of his mandibular left third molar that caused leakage of root canal filling material into the mandibular canal. After radiographic evaluation, extraction of the third molar and distal osteotomy, a surgical exploration was performed and followed by removal of the material and decompression of the IAN. The patient reported an improvement in sensation and immediate disappearance of dysesthesia already from the first postoperative day.

  11. Cleaning and decompression of inferior alveolar canal to treat dysesthesia and paresthesia following endodontic treatment of a third molar.

    Science.gov (United States)

    Scala, Rudy; Cucchi, Alessandro; Cappellina, Luca; Ghensi, Paolo

    2014-01-01

    Endodontic overfilling involving the mandibular canal may cause an injury of the inferior alveolar nerve (IAN). We report a case of disabling dysesthesia and paresthesia of a 70-year-old man after endodontic treatment of his mandibular left third molar that caused leakage of root canal filling material into the mandibular canal. After radiographic evaluation, extraction of the third molar and distal osteotomy, a surgical exploration was performed and followed by removal of the material and decompression of the IAN. The patient reported an improvement in sensation and immediate disappearance of dysesthesia already from the first postoperative day.

  12. Assessing apical transportation in curved canals: comparison between cross-sections and micro-computed tomography

    Directory of Open Access Journals (Sweden)

    Laila Gonzales Freire

    2012-06-01

    Full Text Available The aim of this study was to compare two methods of assessing apical transportation in curved canals after rotary instrumentation, namely, cross-sections and micro-computed tomography (µCT. Thirty mandibular molars were divided into two groups and prepared according to the requirements of each method. In G1 (cross-sections, teeth were embedded in resin blocks and sectioned at 2.0, 3.5, and 5.0 mm from the anatomic apex. Pre- and postoperative sections were photographed and analyzed. In G2 (µCT, teeth were embedded in a rubber-base impression material and scanned before and after instrumentation. Mesiobuccal canals were instrumented with the Twisted File (TF system (SybronEndo, Orange, USA, and mesiolingual canals, with the EndoSequence (ES system (Brasseler, Savannah, USA. Images were reconstructed, and sections corresponding to distances 2.0, 3.5, and 5.0 mm from the anatomic apex were selected for comparison. Data were analyzed using Mann-Whitney's test at a 5% significance level. The TF and ES instruments produced little deviation from the root canal center, with no statistical difference between them (P > 0.05. The canal transportation results were significantly lower (0.056 mm in G2 than in G1 (0.089 mm (p = 0.0012. The µCT method was superior to the cross-section method, especially in view of its ability to preserve specimens and provide results that are more closely related to clinical situations.

  13. Assessment of Marginal Adaptation and Sealing Ability of Root Canal Sealers: An in vitro Study.

    Science.gov (United States)

    Remy, Vimal; Krishnan, Vineesh; Job, Tisson V; Ravisankar, Madhavankutty S; Raj, C V Renjith; John, Seena

    2017-12-01

    This study aims to compare the marginal adaptation and sealing ability [mineral trioxide aggregate (MTA)-Fillapex, AH Plus, Endofill sealers] of root canal sealers. In the present study, the inclusion criteria include 45 single-rooted extracted mandibular premolar teeth, with single canal and complete root formation. The sectioning of the samples was done at the cementoenamel junction using a low-speed diamond disc. Step-back technique was used to prepare root canals manually. The MTA-Fillapex, AH Plus, and Endofill sealers were the three experimental sealer groups to which 45 teeth were distributed. Under scanning electron microscope (SEM), marginal gap at sealer and root dentin interface were examined at coronal and apical halves of root canal. Among the three maximum marginal adaptations were seen with AH Plus sealer (4.10 ± 0.10) which is followed by Endofill sealer (1.44 ± 0.18) and MTA-Fillapex sealer (0.80 ± 0.22). Between the coronal and apical marginal adaptation, significant statistical difference (p = 0.001) was seen in AH Plus sealer. When a Mann-Whitney U-test was done on MTA-Fillapex sealer vs AH Plus sealer and AH Plus sealer vs Endofill sealer, there was a statistically significant difference (p marginal adaptation when compared with other sealers used. For sealing space of crown wall and main cone in root canal treatment, sealers play an important role. The other advantages of sealers are that they are used to fill voids and irregularities in root channel, secondary, lateral channels, and space between applied gutta-percha cones and also act as tripper during filling.

  14. Hand and ultrasonic instrumentation for orthograde root canal treatment of permanent teeth

    Directory of Open Access Journals (Sweden)

    Vinícius Pedrazzi

    2010-06-01

    Full Text Available Root canal treatment is a frequently performed dental procedure and is carried out on teeth in which irreversible pulpitis has led to necrosis of the dental pulp. Removal of the necrotic tissue remnants and cleaning and shaping of the root canal are important phases of root canal treatment. Treatment options include the use of hand and rotary instruments and methods using ultrasonic or sonic equipment. OBJECTIVES: The objectives of this systematic review of randomized controlled trials were to determine the relative clinical effectiveness of hand instrumentation versus ultrasonic instrumentation alone or in conjunction with hand instrumentation for orthograde root canal treatment of permanent teeth. MATERIAL AND METHODS: The search strategy retrieved 226 references from the Cochrane Oral Health Group Trials Register (7, the Cochrane Central Register of Controlled Trials (CENTRAL (12, MEDLINE (192, EMBASE (8 and LILACS (7. No language restriction was applied. The last electronic search was conducted on December 13th, 2007. Screening of eligible studies was conducted in duplicate and independently. RESULTS: Results were to be expressed as fixed-effect or random-effects models using mean differences for continuous outcomes and risk ratios for dichotomous outcomes with 95% confdence intervals. Heterogeneity was to be investigated including both clinical and methodological factors. No eligible randomized controlled trials were identifed. CONCLUSIONS: This review illustrates the current lack of published or ongoing randomized controlled trials and the unavailability of high-level evidence based on clinically relevant outcomes referring to the effectiveness of ultrasonic instrumentation used alone or as an adjunct to hand instrumentation for orthograde root canal treatment. In the absence of reliable research-based evidence, clinicians should base their decisions on clinical experience, individual circumstances and in conjunction with patients

  15. In vitro antimicrobial activity of root canal sealers and calcium hydroxide paste

    Directory of Open Access Journals (Sweden)

    Alessandro L Cavalcanti

    2010-01-01

    Full Text Available Aim: To evaluate the in vitro antimicrobial activity of different root canal sealers and calcium hydroxide (CH paste. Materials and Methods: The sample was composed of two sealers (Fill Canal® and Sealer 26® , one CH cement (Hydro C® , and a CH paste. The agar diffusion test was performed in Petri dishes inoculated with the following microorganisms: Streptococcus salivarius, Streptococcus oralis, Streptococcus mitis, Lactobacillus casei, Streptococcus mutans, Candida albicans, Candida krusei, and Candida tropicalis. The diameters of the zones of microbial growth inhibition were measured after 24 h. The tests were performed in triplicate. Data were analyzed statistically by ANOVA and Tukey′s test at 5% significance level. Results: Fill Canal® exhibited the largest mean zone of microbial growth inhibition against the Candida species and differed significantly from the other groups (P < 0.001. When inhibition was observed against S. mitis and S. oralis, the CH paste presented a larger mean zone of microbial growth inhibition than those of the other materials (P < 0.05. Regarding the inhibition of S. mutans, a statistically significant difference was observed only between the CH paste and Hydro C® (P < 0.05; the paste produced the largest mean zone of microbial growth inhibition against this microorganism. Regarding the inhibition of S. salivarius, Fill Canal® presented smaller mean zone of microbial growth inhibition than Sealer 26® and CH paste (P < 0.05. Conclusion: All the materials presented zones of microbial growth inhibition against all the test bacteria. Fill Canal® presented the largest mean zone of inhibition against the Candida species. For the Streptococcus cultures, none of the sealers presented inhibition superior to that of the CH paste.

  16. Supporting inland waterway transport on German waterways by operational forecasting services - water-levels, discharges, river ice

    Science.gov (United States)

    Meißner, Dennis; Klein, Bastian; Ionita, Monica; Hemri, Stephan; Rademacher, Silke

    2017-04-01

    Inland waterway transport (IWT) is an important commercial sector significantly vulnerable to hydrological impacts. River ice and floods limit the availability of the waterway network and may cause considerable damages to waterway infrastructure. Low flows significantly affect IWT's operation efficiency usually several months a year due to the close correlation of (low) water levels / water depths and (high) transport costs. Therefore "navigation-related" hydrological forecasts focussing on the specific requirements of water-bound transport (relevant forecast locations, target parameters, skill characteristics etc.) play a major role in order to mitigate IWT's vulnerability to hydro-meteorological impacts. In light of continuing transport growth within the European Union, hydrological forecasts for the waterways are essential to stimulate the use of the free capacity IWT still offers more consequently. An overview of the current operational and pre-operational forecasting systems for the German waterways predicting water levels, discharges and river ice thickness on various time-scales will be presented. While short-term (deterministic) forecasts have a long tradition in navigation-related forecasting, (probabilistic) forecasting services offering extended lead-times are not yet well-established and are still subject to current research and development activities (e.g. within the EU-projects EUPORIAS and IMPREX). The focus is on improving technical aspects as well as on exploring adequate ways of disseminating and communicating probabilistic forecast information. For the German stretch of the River Rhine, one of the most frequented inland waterways worldwide, the existing deterministic forecast scheme has been extended by ensemble forecasts combined with statistical post-processing modules applying EMOS (Ensemble Model Output Statistics) and ECC (Ensemble Copula Coupling) in order to generate water level predictions up to 10 days and to estimate its predictive

  17. 76 FR 60076 - Lower Mississippi River Waterway Safety Advisory Committee; Vacancies

    Science.gov (United States)

    2011-09-28

    ... navigable waterways, including the Gulf of Mexico. 1. Five members representing River Port Authorities... consecutive terms. All members serve at their own expense and receive no salary reimbursement of travel...

  18. 76 FR 13422 - Lower Mississippi River Waterway Safety Advisory Committee; Vacancies

    Science.gov (United States)

    2011-03-11

    ... the Lower Mississippi River and its connecting navigable waterways, including the Gulf of Mexico. The... receive no salary, reimbursement of travel expenses, or other compensation from the Federal Government...

  19. Rotary nickel-titanium GT and ProTaper files for root canal shaping by novice operators: a radiographic and micro-computed tomography evaluation.

    Science.gov (United States)

    Gekelman, Diana; Ramamurthy, Ramya; Mirfarsi, Sahar; Paqué, Frank; Peters, Ove A

    2009-11-01

    The purpose of this study was to assess canal preparation outcomes in vitro by novice clinicians after standardized teaching sessions. All students received a training session. In experiment 1, twenty canals of mandibular molars were prepared with GT and ProTaper rotaries by 10 students. Standardized radiographs were exposed before and after canal preparation, and canal curvature was measured; canals were assessed for patency and preparation time. In experiment 2, mandibular molars (20 canals) were submitted to microcomputed tomography before and after canal preparation with ProTaper and GT rotaries by 2 dental students. Canals were metrically assessed for changes (volume, surface, cross-sectional shape, transportation) during canal preparation by using software. In experiment 1, canal curvature decreased by 7.6 degrees and 7.8 degrees for GT and ProTaper preparations; there were no broken instruments, and 2 canals lost patency. The time for GT preparation was longer than for ProTaper (29.7 +/- 6.8 vs 19.4 +/- 8.1 minutes, P session.

  20. An In Vitro Study of the Number of Distal Roots and Canals in mandibular First Molars in Iranian Population.

    Science.gov (United States)

    Razmi, Hasan; Shokouhinejad, Noushin; Hooshyar, Mohsen

    2008-01-01

    The purpose of this study was to evaluate the number of distal roots and canals in mandibular first molars and their internal anatomy radiographically within Iranian population. A total of 310 distal roots of mandibular first molars were incorporated in this study and evaluated in terms of number of roots and number and types of canals. Root canal systems were studied in vitro by means of radiography and based on Vertucci's classifications. It was shown that 4.5% of the teeth in this study had two distal roots, of which, 100% indicated type I for both distobuccal and distolingual roots. Among all the teeth, 43.2% had two canals, 24.2% two apical foramina, and 38.7% two orifices in their distal roots. According to Vertucci's classification 54.9% of the teeth were type I, 19% type II, 1.9% type III, 14.2% type IV, 4.2% type V, 1% type VI, 0.3% type VII and 0% type VIII. In as many as 43.2% of all teeth assessed in this study, bicanaled distal roots were observed, dentists are always recommended to search for the second canal in distal roots of mandibular first molars. In case the second canal in the distal root is missed, failure of endodontic treatment will be anticipated. A rectangular type access cavity design allows better visualization and negotiation of the probable second canals within the distal roots of mandibular first molars.

  1. Innovative 'Artificial Mussels' technology for assessing spatial and temporal distribution of metals in Goulburn-Murray catchments waterways, Victoria, Australia: effects of climate variability (dry vs. wet years).

    Science.gov (United States)

    Kibria, Golam; Lau, T C; Wu, Rudolf

    2012-12-01

    The "Artificial mussel" (AM), a novel passive sampling technology, was used for the first time in Australia in freshwater to monitor and assess the risk of trace metals (Cd, Cu, Hg, Pb, and Zn). AMs were deployed at 10 sites within the Goulburn-Murray Water catchments, Victoria, Australia during a dry year (2009-2010) and a wet year (2010-2011). Our results showed that the AMs accumulated all the five metals. Cd, Pb, Hg were detected during the wet year but below detection limits during the dry year. At some sites close to orchards, vine yards and farming areas, elevated levels of Cu were clearly evident during the dry year, while elevated levels of Zn were found during the wet year; the Cu indicates localized inputs from the agricultural application of copper fungicide. The impacts from old mines were significantly less compared 'hot spots'. Our study demonstrated that climate variability (dry, wet years) can influence the metal inputs to waterways via different transport pathways. Using the AMs, we were able to identify various 'hot spots' of heavy metals, which may pose a potential risk to aquatic ecosystems (sub-lethal effects to fish) and public (via food chain metal bioaccumulation and biomagnification) in the Goulburn-Murray Water catchments. The State Protection Policy exempted artificial channels and drains from protection of beneficial use (including protection of aquatic ecosystems) and majority of sites ('hot spots') were located within artificial irrigation channels. Copyright © 2012 Elsevier Ltd. All rights reserved.

  2. Assessment of the relationship between the mandibular third molar and the mandibular canal using panoramic radiograph and cone beam computed tomography

    International Nuclear Information System (INIS)

    Jung, Yun Hoa; Nah, Kyung Soo; Cho, Bong Hae

    2008-01-01

    The purpose of this study is to evaluate the position of the mandibular canal in relation to the mandibular third molar by cone beam CT in cases showing a close relationship between the third molar and the mandibular canal on the panoramic radiograph. The panoramic images and cone beam CT scans of 87 impacted mandibular third molars in 60 patients were evaluated to assess the tooth relationship to the mandibular canal. The clearness of the canal wall and the vertical depth of the lower third molar were evaluated on panoramic radiographs. The lower third molars were assessed using cone beam CT to determine the proximity and position of the canal relative to the roots. In the 66 cases where the canal wall was unclear on the panoramic radiographs, 58 (87.9%) of the third molars had contact between the canal and root; 34 (51.5%) canals were showed an inferior position and 22 (33.3%) showed a linguoinferior position on cone beam CT. Interruption of the canal wall on panoramic radiographs was highly predictive of contact between the mandibular canal and the third molar. Cross sectional CT may be indicated for localization of the mandibular canal in such cases.

  3. Hand and nickel-titanium root canal instrumentation performed by dental students: a micro-computed tomographic study.

    Science.gov (United States)

    Peru, M; Peru, C; Mannocci, F; Sherriff, M; Buchanan, L S; Pitt Ford, T R

    2006-02-01

    The aim of this study was to evaluate root canals instrumented by dental students using the modified double-flared technique, nickel-titanium (NiTi) rotary System GT files and NiTi rotary ProTaper files by micro-computed tomography (MCT). A total of 36 root canals from 18 mesial roots of mandibular molar teeth were prepared; 12 canals were prepared with the modified double-flared technique, using K-flexofiles and Gates-Glidden burs; 12 canals were prepared using System GT and 12 using ProTaper rotary files. Each root was scanned using MCT preoperatively and postoperatively. At the coronal and mid-root sections, System GT and ProTaper files produced significantly less enlarged canal cross-sectional area, volume and perimeter than the modified double-flared technique (P ProTaper (P ProTaper and System GT were able to prepare root canals with little or no procedural error compared with the modified double-flared technique. Under the conditions of this study, inexperienced dental students were able to prepare curved root canals with rotary files with greater preservation of tooth structure, low risk of procedural errors and much quicker than with hand instruments.

  4. Comparative study of the macroscopic finding, conventional tomographic imaging, and computed tomographic imaging in locating the mandibular canal

    International Nuclear Information System (INIS)

    Choi, Hang Moon; You, Dong Soo

    1995-01-01

    The purpose of this study was comparison of conventional tomography with reformatted computed tomography for dental implant in locating the mandibular canal. Five dogs were used and after conventional tomographs and fitted computed tomographs were taken, four dentist traced all films. Mandibles were sectioned with 2 mm slice thickness and the sections were then radiographed (contact radiography). Each radiograpic image was traced and linear measurements were made from mandibular canal to alveolar crest, buccal cortex, lingual cortex, and inferior border. The following results were obtained; 1. Reformatted computed tomographs were exacter than conventional tomography by alveolar crest to canal length of -0.6 mm difference between real values and radiographs 2. The average measurements of buccal cortex to mandibular canal width and lingual cortex to mandibular canal width of conventional tomographs were exacter than reformatted computed tomographs, but standard deviations were higher than reformatted computed tomographs. 3. Standard deviations of reformatted computed tomographs were lower than conventional tomographs at all comparing sites 4. At reformatted computed tomography 62.5% of the measurements performed were within ±1 mm of the true value, and at conventional tomography 24.1% were. 5. Mandibular canal invisibility was 0.8% at reformatted computed tomography and 9.2% at conventional tomography. Reformatted computed tomography has been shown to be more useful radiographic technique for assessment of the mandibular canal than conventional tomography.

  5. Endodontic Treatment of Maxillary Premolar with Three Root Canals Using Optical Microscope and NiTi Rotatory Files System.

    Science.gov (United States)

    Relvas, João Bosco Formiga; de Carvalho, Fredsom Marcio Acris; Marques, André Augusto Franco; Sponchiado, Emílio Carlos; Garcia, Lucas da Fonseca Roberti

    2013-01-01

    The aim of the study was to report a clinical case of endodontic treatment of a maxillary first premolar with three root canals using an optical microscope and rotary instrumentation technique. The main complaint of the patient, a 16-year-old girl, was pain in tooth 14. After clinical and radiographic examination, irreversible pulpitis was diagnosed. An alteration in the middle third of the pulp chamber radiographically observed suggested the presence of three root canals. Pulp chamber access and initial catheterization using size number 10 K-files were performed. The optical microscope and radiographic examination were used to confirm the presence of three root canals. PathFiles #13, #16, and #19 were used to perform catheterization and ProTaper files S1 and S2 for cervical preparation. Apical preparation was performed using F1 file in the buccal canals and F2 in the palatal canal up to the working length. The root canals were filled with Endofill sealer by thermal compaction technique using McSpadden #50. The case has been receiving follow-up for 12 months and no painful symptomatology or periapical lesions have been found. The use of technological tools was able to assist the endodontic treatment of teeth with complex internal anatomy, such as three-canal premolars.

  6. Pedicle distraction increases intervertebral and spinal canal area in a cadaver and bone model

    OpenAIRE

    Hughes Matthew; Papadakos Nikolaos; Bishop Tim; Bernard Jason

    2018-01-01

    Introduction: Lumbar spinal stenosis is degenerative narrowing of the spinal canal and/or intervertebral foramen causing compression of the spinal cord and nerve roots. Traditional decompression techniques can often cause significant trauma and vertebral instability. This paper evaluates a method of increasing pedicle length to decompress the spinal and intervertebral foramen, which could be done minimally invasive. Methods: Three Sawbone (Sawbones Europe, Sweden) and 1 cadaveric lumbar sp...

  7. China Pakistan Economic Corridor (CPEC): Benefits For Pakistan And Comparison With Suez And Panama Canals

    Science.gov (United States)

    2017-12-01

    ECONOMIC CORRIDOR (CPEC): BENEFITS FOR PAKISTAN AND COMPARISON WITH SUEZ AND PANAMA CANALS by Hanif Ullah Khan December 2017 Thesis...DATE December 2017 3. REPORT TYPE AND DATES COVERED Master’s thesis 4. TITLE AND SUBTITLE CHINA PAKISTAN ECONOMIC CORRIDOR (CPEC): BENEFITS FOR...The China Pakistan Economic Corridor (CPEC) is part of China’s “One Belt, One Road” initiative and joins two major economic corridors: The Silk Road

  8. Morphological analysis of the cervical spinal canal, dural tube and spinal cord in normal individuals using CT myelography

    International Nuclear Information System (INIS)

    Inoue, H.; Ohmori, K.; Takatsu, T.; Teramoto, T.; Ishida, Y.; Suzuki, K.

    1996-01-01

    To verify the conventional concept of ''developmental stenosis of the cervical spinal canal'', we performed a morphological analysis of the relations of the cervical spinal canal, dural tube and spinal cord in normal individuals. The sagittal diameter, area and circularity of the three structures, and the dispersion of each parameter, were examined on axial sections of CT myelograms of 36 normal subjects. The spinal canal was narrowest at C4, followed by C5, while the spinal cord was largest at C4/5. The area and circularity of the cervical spinal cord were not significantly correlated with any parameter of the spinal canal nor with the sagittal diameter and area of the dural tube at any level examined, and the spinal cord showed less individual variation than the bony canal. Compression of the spinal cord might be expected whenever the sagittal diameter of the spinal canal is below the lower limit of normal, that is about 12 mm on plain radiographs. Thus, we concluded that the concept of ''developmental stenosis of the cervical spinal canal'' was reasonable and acceptable. (orig.). With 2 figs., 3 tabs

  9. CT evaluation of canal preparation using rotary and hand NI-TI instruments: An in vitro study

    Science.gov (United States)

    Nagaraja, Shruthi; Sreenivasa Murthy, B V

    2010-01-01

    Background: Controlled, uniformly tapered radicular preparation is a great challenge in endodontics. Improper preparation can lead to procedural errors like transportation of foramen, uneven dentine thickness, stripping of root canal, formation of ledge, zip, and elbow in curved canals. These procedural errors and their sequel can adversely affect the prognosis of treatment. Aim/Objectives: The present in vitro study aims to evaluate canal preparation based on the following factors: canal transportation, remaining dentine thickness and comparing centering ability between hand Ni-Ti K files and ProTaper rotary Ni-Ti instruments using computed tomography (CT). Materials and Methods: For evaluation, 30 mesiobuccal roots of maxillary molars were selected. Of these, 15 roots were distributed into two groups where Group 1 included hand instrumentation with Ni-Ti K-files; and Group 2 comprised ProTaper NiTi rotary system. Pre instrumentation and post instrumentation three-dimensional CT images were obtained from root cross-sections that were 1 mm thick from apex to the canal orifice; scanned images were then superimposed and compared. Result: It was observed that the manual technique using hand Ni-Ti K-file produced lesser canal transportation and maintained greater dentine thickness than the rotary ProTaper technique at middle and coronal third and this difference was statistically significant. No significant difference was seen with regard to canal transportation and remaining root dentine at apical levels. With regard to centering ratio, no significant difference was seen between both the groups at all levels. Conclusion: ProTaper should be used judiciously, especially in curved canals, as it causes higher canal transportation and thinning of root dentine at middle and coronal levels. None of the groups showed optimal centering ability. PMID:20582214

  10. Masses and disease entities of the external auditory canal: Radiological and clinical correlation

    Energy Technology Data Exchange (ETDEWEB)

    White, R.D., E-mail: richard.white3@nhs.net [Department of Clinical Radiology, Ninewells Hospital and Medical School, Dundee (United Kingdom); Ananthakrishnan, G. [Department of Clinical Radiology, Ninewells Hospital and Medical School, Dundee (United Kingdom); McKean, S.A. [Department of Otolaryngology, Ninewells Hospital and Medical School, Dundee (United Kingdom); Brunton, J.N. [Department of Clinical Radiology, Ninewells Hospital and Medical School, Dundee (United Kingdom); Hussain, S.S.M. [Department of Otolaryngology, Ninewells Hospital and Medical School, Dundee (United Kingdom); Sudarshan, T.A. [Department of Clinical Radiology, Ninewells Hospital and Medical School, Dundee (United Kingdom)

    2012-02-15

    A wide spectrum of disease entities can affect the external auditory canal (EAC). This review describes the normal anatomy of the EAC. Congenital abnormalities, infections, neoplasms, and miscellaneous conditions, such as cholesteatoma and acquired stenosis, are shown with reference to clinical relevance and management. Cases have been histologically confirmed, where relevant. The EAC is frequently imaged - for example, on cross-sectional imaging of the brain - and this review should stimulate radiologists to include it as an important area for review.

  11. CT evaluation of canal preparation using rotary and hand NI-TI instruments: An in vitro study.

    Science.gov (United States)

    Nagaraja, Shruthi; Sreenivasa Murthy, B V

    2010-01-01

    Controlled, uniformly tapered radicular preparation is a great challenge in endodontics. Improper preparation can lead to procedural errors like transportation of foramen, uneven dentine thickness, stripping of root canal, formation of ledge, zip, and elbow in curved canals. These procedural errors and their sequel can adversely affect the prognosis of treatment. The present in vitro study aims to evaluate canal preparation based on the following factors: canal transportation, remaining dentine thickness and comparing centering ability between hand Ni-Ti K files and ProTaper rotary Ni-Ti instruments using computed tomography (CT). For evaluation, 30 mesiobuccal roots of maxillary molars were selected. Of these, 15 roots were distributed into two groups where Group 1 included hand instrumentation with Ni-Ti K-files; and Group 2 comprised ProTaper NiTi rotary system. Pre instrumentation and post instrumentation three-dimensional CT images were obtained from root cross-sections that were 1 mm thick from apex to the canal orifice; scanned images were then superimposed and compared. It was observed that the manual technique using hand Ni-Ti K-file produced lesser canal transportation and maintained greater dentine thickness than the rotary ProTaper technique at middle and coronal third and this difference was statistically significant. No significant difference was seen with regard to canal transportation and remaining root dentine at apical levels. With regard to centering ratio, no significant difference was seen between both the groups at all levels. ProTaper should be used judiciously, especially in curved canals, as it causes higher canal transportation and thinning of root dentine at middle and coronal levels. None of the groups showed optimal centering ability.

  12. Geometric Modeling of the Machine for Cutting Cane and Other Aquatic Plants in Navigable Waterways by Agustín de Betancourt y Molina

    Directory of Open Access Journals (Sweden)

    José Ignacio Rojas-Sola

    2018-02-01

    Full Text Available This article presents the steps followed to obtain a three-dimensional model of one of the most recognized historical inventions of Agustín de Betancourt y Molina from the scant documentation found about it. Specifically, this was a machine for cutting cane and other aquatic plants in navigable waterways, presented in London in 1795. The study is based on computer-aided design (CAD techniques using Autodesk Inventor Professional, from the information provided by the only two sheets that exist from the machine, one with specifications in English and the other in French, both very similar. In order to obtain a functional result on which to carry out further studies, it has been necessary to make some geometrical hypotheses on the models, aimed to find the correct dimension of each element. In addition, it has also been necessary to define the relationship of each element with those that set up its environment, defining movement restrictions, so that the final model, behaves as real as possible.

  13. An observational study on the temperature rising effects in water warming canal and water warming pond

    Energy Technology Data Exchange (ETDEWEB)

    Hong, J. B.; Hong, S. B. [Rural Development Cooperation, Seoul (Korea, Republic of)

    1990-09-15

    The power water flowed out from the multipurpose darn influences the ecosystem approximately because of the low water temperature. An appropriate counter measure to the rising water temperature is needed for growing crops especially when the temperature is below 18°C in the source of the irrigation water This observational study is practiced in Yong-Doo water warming canal and pond in the down stream of Choong-Ju multipurpose dam and is practiced for analyse and compare the rising effects in actural water temperature by actual measurement with the rising effects of planned water temperatuer by the basic theoritical method and for the help to present the direction in plan establishment through investigate the results afterwards. The results are as follows. 1. The degree of the rise of the water temperature can be decided by θ{sub x} = θ{sub 0} + K (L/(v * h)) * (T - θ{sub 0}) Then, K values of a factor representing the characteristics of the water warming canal were 0.00002043 for the type I. and 0.0000173 for the type II. respectively. 2. A variation of water temperature which produced by the difference effective temperature and water temperature in the water warming canal was θ{sub x1} = 16.5 + 15.9 (1-e{sup -0.00018x}), θ{sub x2} = 18.8 + 8.4(1-e{sup -0.000298x}) for the type I. and θ{sub x} = 19.6 + 12.8 (1-e{sup -0.00041x}) for the type II. 3. It was shown that the effects of the rise of water temperature for the type I. water warming canal were greater than that of type II. as a resultes of broadening the surface of the canal compared with the depth of water, coloring the surface of water canal and installing the resistance block. 4. In case of the type I. water warming canal, the equation between the air temperature and the degree of the rise of water temprature could be made; Y = 0.4134X + 7.728 In addition, in case of the type II. water warming canal, the correlation was very low. 5. A monthly variation of the water temperature in the water warming

  14. Occurrence and distribution of Malassezia species on skin and external ear canal of horses.

    Science.gov (United States)

    Shokri, Hojjatollah

    2016-01-01

    The aim of this study was to investigate the prevalence of Malassezia species from the body skin and external ear canal of healthy horses. The samples were obtained by scraping the skin surface from the nose, groin and dorsum and swabbing from the external ear canal of 163 animals, and then incubated on sabouraud dextrose agar and modified Dixon agar. Malassezia species were isolated from 34.9% of horses. The percentages of Malassezia species were 64.3% for Arab, 35.7% for Persian, 35.4% for Thoroughbred and 27.1% for Turkmen breeds. The greatest abundance of Malassezia species was found in the external ear canal (47.7%, representing significant difference with other sites), followed by nose (26.3%), groin (15.8%) and dorsum (10.5%) (P horses varies by body site and age but not by breed and gender, representing M. pachydermatis as the most prevalent species on horse skin. © 2015 Blackwell Verlag GmbH.

  15. Analysis of kinematic, kinetic and electromyographic patterns during root canal preparation with rotary and manual instruments

    Directory of Open Access Journals (Sweden)

    Braulio Pasternak-Júnior

    2012-02-01

    Full Text Available OBJECTIVE: This study assessed the muscular activity during root canal preparation through kinematics, kinetics, and electromyography (EMG. MATERIAL AND METHODS: The operators prepared one canal with RaCe rotary instruments and another with Flexo-files. The kinematics of the major joints was reconstructed using an optoelectronic system and electromyographic responses of the flexor carpi radialis, extensor carpi radialis, brachioradialis, biceps brachii, triceps brachii, middle deltoid, and upper trapezius were recorded. The joint torques of the shoulder, elbow and wrist were calculated using inverse dynamics. In the kinematic analysis, angular movements of the wrist and elbow were classified as low risk factors for work-related musculoskeletal disorders. With respect to the shoulder, the classification was medium-risk. RESULTS: There was no significant difference revealed by the kinetic reports. The EMG results showed that for the middle deltoid and upper trapezius the rotary instrumentation elicited higher values. The flexor carpi radialis and extensor carpi radialis, as well as the brachioradialis showed a higher value with the manual method. CONCLUSION: The muscular recruitment for accomplishment of articular movements for root canal preparation with either the rotary or manual techniques is distinct. Nevertheless, the rotary instrument presented less difficulty in the generation of the joint torque in each articulation, thus, presenting a greater uniformity of joint torques.

  16. Analysis of kinematic, kinetic and electromyographic patterns during root canal preparation with rotary and manual instruments

    Science.gov (United States)

    PASTERNAK-JÚNIOR, Braulio; de SOUSA NETO, Manoel Damião; DIONÍSIO, Valdeci Carlos; PÉCORA, Jesus Djalma; SILVA, Ricardo Gariba

    2012-01-01

    Objective This study assessed the muscular activity during root canal preparation through kinematics, kinetics, and electromyography (EMG). Material and Methods The operators prepared one canal with RaCe rotary instruments and another with Flexo-files. The kinematics of the major joints was reconstructed using an optoelectronic system and electromyographic responses of the flexor carpi radialis, extensor carpi radialis, brachioradialis, biceps brachii, triceps brachii, middle deltoid, and upper trapezius were recorded. The joint torques of the shoulder, elbow and wrist were calculated using inverse dynamics. In the kinematic analysis, angular movements of the wrist and elbow were classified as low risk factors for work-related musculoskeletal disorders. With respect to the shoulder, the classification was medium-risk. Results There was no significant difference revealed by the kinetic reports. The EMG results showed that for the middle deltoid and upper trapezius the rotary instrumentation elicited higher values. The flexor carpi radialis and extensor carpi radialis, as well as the brachioradialis showed a higher value with the manual method. Conclusion The muscular recruitment for accomplishment of articular movements for root canal preparation with either the rotary or manual techniques is distinct. Nevertheless, the rotary instrument presented less difficulty in the generation of the joint torque in each articulation, thus, presenting a greater uniformity of joint torques. PMID:22437679

  17. Critical Uncertainties and Gaps in the Environmental- and Social-Impact Assessment of the Proposed Interoceanic Canal through Nicaragua.

    Science.gov (United States)

    Huete-Pérez, Jorge A; Ortega-Hegg, Manuel; Urquhart, Gerald R; Covich, Alan P; Vammen, Katherine; Rittmann, Bruce E; Miranda, Julio C; Espinoza-Corriols, Sergio; Acevedo, Adolfo; Acosta, María L; Gómez, Juan P; Brett, Michael T; Hanemann, Michael; Härer, Andreas; Incer-Barquero, Jaime; Joyce, Frank J; Lauer, J Wesley; Maes, Jean Michel; Tomson, Mason B; Meyer, Axel; Montenegro-Guillén, Salvador; Whitlow, W Lindsay; Schnoor, Jerald L; Alvarez, Pedro J J

    2016-08-01

    The proposed interoceanic canal will connect the Caribbean Sea with the Pacific Ocean, traversing Lake Nicaragua, the major freshwater reservoir in Central America. If completed, the canal would be the largest infrastructure-related excavation project on Earth. In November 2015, the Nicaraguan government approved an environmental and social impact assessment (ESIA) for the canal. A group of international experts participated in a workshop organized by the Academy of Sciences of Nicaragua to review this ESIA. The group concluded that the ESIA does not meet international standards; essential information is lacking regarding the potential impacts on the lake, freshwater and marine environments, and biodiversity. The ESIA presents an inadequate assessment of natural hazards and socioeconomic disruptions. The panel recommends that work on the canal project be suspended until an appropriate ESIA is completed. The project should be resumed only if it is demonstrated to be economically feasible, environmentally acceptable, and socially beneficial.

  18. 78 FR 62439 - Drawbridge Operation Regulation; Inner Harbor Navigational Canal, New Orleans, LA

    Science.gov (United States)

    2013-10-22

    ... Operation Regulation; Inner Harbor Navigational Canal, New Orleans, LA AGENCY: Coast Guard, DHS. ACTION..../Seabrook) bridge across the IHNC, mile 4.6, both at New Orleans, LA. This deviation will test changes to... Intra-Costal Waterway (GIWW). The US 90 (Danzinger) Bridge across the IHNC, mile 3.1, at New Orleans...

  19. Magmatic evolution of Panama Canal volcanic rocks: A record of arc processes and tectonic change.

    Directory of Open Access Journals (Sweden)

    David W Farris

    Full Text Available Volcanic rocks along the Panama Canal present a world-class opportunity to examine the relationship between arc magmatism, tectonic forcing, wet and dry magmas, and volcanic structures. Major and trace element geochemistry of Canal volcanic rocks indicate a significant petrologic transition at 21-25 Ma. Oligocene Bas Obispo Fm. rocks have large negative Nb-Ta anomalies, low HREE, fluid mobile element enrichments, a THI of 0.88, and a H2Ocalc of >3 wt. %. In contrast, the Miocene Pedro Miguel and Late Basalt Fm. exhibit reduced Nb-Ta anomalies, flattened REE curves, depleted fluid mobile elements, a THI of 1.45, a H2Ocalc of <1 wt. %, and plot in mid-ocean ridge/back-arc basin fields. Geochemical modeling of Miocene rocks indicates 0.5-0.1 kbar crystallization depths of hot (1100-1190°C magmas in which most compositional diversity can be explained by fractional crystallization (F = 0.5. However, the most silicic lavas (Las Cascadas Fm. require an additional mechanism, and assimilation-fractional-crystallization can reproduce observed compositions at reasonable melt fractions. The Canal volcanic rocks, therefore, change from hydrous basaltic pyroclastic deposits typical of mantle-wedge-derived magmas, to hot, dry bi-modal magmatism at the Oligocene-Miocene boundary. We suggest the primary reason for the change is onset of arc perpendicular extension localized to central Panama. High-resolution mapping along the Panama Canal has revealed a sequence of inward dipping maar-diatreme pyroclastic pipes, large basaltic sills, and bedded silicic ignimbrites and tuff deposits. These volcanic bodies intrude into the sedimentary Canal Basin and are cut by normal and subsequently strike-slip faults. Such pyroclastic pipes and basaltic sills are most common in extensional arc and large igneous province environments. Overall, the change in volcanic edifice form and geochemistry are related to onset of arc perpendicular extension, and are consistent with the

  20. Magmatic evolution of Panama Canal volcanic rocks: A record of arc processes and tectonic change

    Science.gov (United States)

    Cardona, Agustin; Montes, Camilo; Foster, David; Jaramillo, Carlos

    2017-01-01

    Volcanic rocks along the Panama Canal present a world-class opportunity to examine the relationship between arc magmatism, tectonic forcing, wet and dry magmas, and volcanic structures. Major and trace element geochemistry of Canal volcanic rocks indicate a significant petrologic transition at 21–25 Ma. Oligocene Bas Obispo Fm. rocks have large negative Nb-Ta anomalies, low HREE, fluid mobile element enrichments, a THI of 0.88, and a H2Ocalc of >3 wt. %. In contrast, the Miocene Pedro Miguel and Late Basalt Fm. exhibit reduced Nb-Ta anomalies, flattened REE curves, depleted fluid mobile elements, a THI of 1.45, a H2Ocalc of arc basin fields. Geochemical modeling of Miocene rocks indicates 0.5–0.1 kbar crystallization depths of hot (1100–1190°C) magmas in which most compositional diversity can be explained by fractional crystallization (F = 0.5). However, the most silicic lavas (Las Cascadas Fm.) require an additional mechanism, and assimilation-fractional-crystallization can reproduce observed compositions at reasonable melt fractions. The Canal volcanic rocks, therefore, change from hydrous basaltic pyroclastic deposits typical of mantle-wedge-derived magmas, to hot, dry bi-modal magmatism at the Oligocene-Miocene boundary. We suggest the primary reason for the change is onset of arc perpendicular extension localized to central Panama. High-resolution mapping along the Panama Canal has revealed a sequence of inward dipping maar-diatreme pyroclastic pipes, large basaltic sills, and bedded silicic ignimbrites and tuff deposits. These volcanic bodies intrude into the sedimentary Canal Basin and are cut by normal and subsequently strike-slip faults. Such pyroclastic pipes and basaltic sills are most common in extensional arc and large igneous province environments. Overall, the change in volcanic edifice form and geochemistry are related to onset of arc perpendicular extension, and are consistent with the idea that Panama arc crust fractured during collision

  1. 33 CFR 165.923 - Regulated Navigation Area between mile markers 296.1 and 296.7 of the Chicago Sanitary and Ship...

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Regulated Navigation Area between mile markers 296.1 and 296.7 of the Chicago Sanitary and Ship Canal located near Romeoville, IL. 165.923 Section 165.923 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY REGULATED...

  2. Freshwater and Saline Loads of Dissolved Inorganic Nitrogen to Hood Canal and Lynch Cove, Western Washington

    Science.gov (United States)

    Paulson, Anthony J.; Konrad, Christopher P.; Frans, Lonna M.; Noble, Marlene; Kendall, Carol; Josberger, Edward G.; Huffman, Raegan L.; Olsen, Theresa D.

    2006-01-01

    Hood Canal is a long (110 kilometers), deep (175 meters) and narrow (2 to 4 kilometers wide) fjord of Puget Sound in western Washington. The stratification of a less dense, fresh upper layer of the water column causes the cold, saltier lower layer of the water column to be isolated from the atmosphere in the late summer and autumn, which limits reaeration of the lower layer. In the upper layer of Hood Canal, the production of organic matter that settles and consumes dissolved oxygen in the lower layer appears to be limited by the load of dissolved inorganic nitrogen (DIN): nitrate, nitrite, and ammonia. Freshwater and saline loads of DIN to Hood Canal were estimated from available historical data. The freshwater load of DIN to the upper layer of Hood Canal, which could be taken up by phytoplankton, came mostly from surface and ground water from subbasins, which accounts for 92 percent of total load of DIN to the upper layer of Hood Canal. Although DIN in rain falling on land surfaces amounts to about one-half of the DIN entering Hood Canal from subbasins, rain falling directly on the surface of marine waters contributed only 4 percent of the load to the upper layer. Point-source discharges and subsurface flow from shallow shoreline septic systems contributed less than 4 percent of the DIN load to the upper layer. DIN in saline water flowing over the sill into Hood Canal from Admiralty Inlet was at least 17 times the total load to the upper layer of Hood Canal. In September and October 2004, field data were collected to estimate DIN loads to Lynch Cove - the most inland marine waters of Hood Canal that routinely contain low dissolved-oxygen waters. Based on measured streamflow and DIN concentrations, surface discharge was estimated to have contributed about one-fourth of DIN loads to the upper layer of Lynch Cove. Ground-water flow from subbasins was estimated to have contributed about one-half of total DIN loads to the upper layer. In autumn 2004, the relative

  3. Traumatic facial nerve palsy: CT patterns of facial nerve canal fracture and correlation with clinical severity

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Jae Cheol; Kim, Sang Joon; Park, Hyun Min; Lee, Young Suk; Lee, Jee Young [College of Medicine, Dankook Univ., Chonan (Korea, Republic of)

    2002-07-01

    To analyse the patterns of facial nerve canal injury seen at temporal bone computed tomography (CT) in patients with traumatic facial nerve palsy and to correlate these with clinical manifestations and outcome. Thirty cases of temporal bone CT in 29 patients with traumatic facial nerve palsy were analyzed with regard to the patterns of facial nerve canal involvement. The patterns were correlated with clinical grade, the electroneurographic (ENoG) findings, and clinical outcome. For clinical grading, the House-Brackmann scale was used, as follows:grade I-IV, partial palsy group; grade V-VI, complete palsy group. The electroneuronographic findings were categorized as mild to moderate (below 90%) or severe (90% and over) degeneration. In 25 cases, the bony wall of the facial nerve canals was involved directly (direct finding): discontinuity of the bony wall was onted in 22 cases, bony spicules in ten, and bony wall displacement in five. Indirect findings were canal widening in nine cases and adjacent bone fracture in two. In one case, there were no direct or indirect findings. All cases in which there was complete palsy (n=8) showed one or more direct findings including spicules in six, while in the incomplete palsy group (n=22), 17 cases showed direct findings. In the severe degeneration group (n=13), on ENog, 12 cases demonstrated direct findings, including spicules in nine cases. In 24 patients, symptoms of facial palsy showed improvement at follow up evaluation. Four of the five patients in whom symptoms did not improve had spicules. Among ten patients with spicules, five underwent surgery and symptoms improved in four of these; among the five patients not operated on , symptoms did not improve in three. In most patients with facial palsy after temporal bone injury, temporal bone CT revealed direct or indirect facial nerve canal involvement, and in complete palsy or severe degeneration groups, there were direct findings in most cases. We believe that meticulous

  4. Carbon footprint of construction, operation and maintenance of waterways and traffic; Merenkulun ja liikenteen hiilijalanjaelki. Osa 1: Merenkulun hiilijalanjaelki, Osa 2: Tie-, rata- ja meriliikenteen hiilijalanjaeljet

    Energy Technology Data Exchange (ETDEWEB)

    Illman, J.; Kumpulainen, A.; Pesola, A.; Vanhanen, J.

    2012-07-01

    through them. In the second part of this project, emissions caused by traffic operating on the road and rail networks and waterways were calculated. The sources of emissions were first identified and categorised into primary and secondary emissions. Primary emissions include the greenhouse gas emissions from fuels used by vehicles. Secondary emissions result from operations that enable traffic to flow such as the energy used by gas stations and railway stations or the construction and maintenance of parking areas. It was concluded that the emissions caused by traffic are significantly larger than those of constructing, using and maintaining the transport infrastructure. The infrastructure of the road network has a carbon footprint of 511 000 tCO{sub 2}/a, while the emissions of traffic on the network are around 8,3 MtCO{sub 2}/a. The emissions of the main railway infrastructure are approximately 142 000 tCO{sub 2}/a and railway traffic has a carbon footprint of 315 000 tCO{sub 2}/a. For waterways the infrastructure emissions are 150 000 tCO{sub 2}/a and the emissions caused by traffic 2,4 MtCO{sub 2}/a. The share of secondary emissions of total emissions remains small. (orig.)

  5. Evaluation of Control and Adjustment Structures of the Shibab Main Canal Using HEC-RAS

    Directory of Open Access Journals (Sweden)

    maryam mohammadi

    2017-02-01

    Full Text Available Introduction: Poor performance of irrigation and drainage networks causes to reduce the transfer and distribution throughputs and in result comes useless water and makes too much consumption in forming. A significant portion of water losses in irrigation and drainage networksis related to transmission and distribution. Therefor more consideration in thrirrigation network management, improve irrigation efficiency and also the exploitation of water resources, especially in the agricultural sector is necessary. Controlling and adjusting structures of water level in the direction of drainage and irrigation canals can influence on increasing of throughput and decrease the use of water. So, right choosing and recognition of the deficiencies of these structures helps carry up the throughput of the networks and prevents to waste water. It is hard to solve equations of water flow in canals and related institutions by using analytic methods. For this reason, this research was done with HEC-RAS hydraulical model in the main channelof irrigation and drainage network of Sistan plain. Materials and Methods: Sistan plain is located in southeastern of Iran with good potential for agricultural production because of the alluvial sediments from Hirmand River. 23820 ha of the Sistan plain is covered by 5 blocksof the Shibab irrigation and drainage network. While Sistan’sShibab irrigation network efficiency is low, HEC-RAS Hydraulics model in unsteady condition was performed to control and adjust this network’s main canal in approximately 19 Km length. In this research, the evaluation model in the canal was performed for more suitable intakingwater in the quadruple order 2 canals . So, the existing structure’s operation was analyzed on controlling structures in management and lack of management situations.This research was assessed during a 15-day impounding period using hydraulic model of HEC-RAS with the aim of performance and operation evaluation of

  6. Unpredictable Root Canal Morphology: Expect the Unexpected

    Directory of Open Access Journals (Sweden)

    Sohez J Makani

    2015-01-01

    Full Text Available Background: A maxillary first molar with more than four canals is an interesting example of anatomic variations, especially when two of these canals are detected, with separate apical foramen in the distal root. The inability to locate the unexpected canals of various anatomical configuration and subsequently treat them , may lead to therapeutic failures. Endodontic retreatment is usually the modality of choice in such cases. This report describes a case of a maxillary first molar with five canals (two mesial canals in mesial root, two distal canals in two distal roots and a palatal canal in palatal root. Additionally it shows a rare anatomic configuration and emphasizes the importance of identifying additional canals.

  7. Duwamish Waterways Navigation Improvement Study: Review of Existing Information on Land-Use Plans and Aquatic Resources in and Adjacent to the Duwamish River and Elliott Bay, Washington

    Science.gov (United States)

    1980-06-01

    Species of Narine Aimals . U.S. Army Corps of Nngineers., Dredged Material Research Program, Waterways Experiment Station. Tech. Report D-77-24, 22 pages...shoreline substrates to hard substrates have been suggested. Juvenile salmon may be delayed by physical barriers, may suffer increased predation if...contents of each species at each station, food habit2 can be estimated. Stomach analysis of any potential predator species captured during the study may

  8. Endodontic treatment of a C-shaped mandibular second premolar with four root canals and three apical foramina: a case report

    Directory of Open Access Journals (Sweden)

    Thikamphaa Bertrand

    2016-02-01

    Full Text Available This case report describes a unique C-shaped mandibular second premolar with four canals and three apical foramina and its endodontic management with the aid of cone-beam computer tomography (CBCT. C-shaped root canal morphology with four canals was identified under a dental operating microscope. A CBCT scan was taken to evaluate the aberrant root canal anatomy and devise a better instrumentation strategy based on the anatomy. All canals were instrumented to have a 0.05 taper using 1.0 mm step-back filing with appropriate apical sizes determined from the CBCT scan images and filled using a warm vertical compaction technique. A C-shaped mandibular second premolar with multiple canals is an anatomically rare case for clinicians, yet its endodontic treatment may require a careful instrumentation strategy due to the difficulty in disinfecting the canals in the thin root area without compromising the root structure.

  9. Application of GIS tools in determining the navigability of waterways

    Science.gov (United States)

    Nadolny, Grzegorz; Rabant, Hubert; Szatten, Dawid

    2017-11-01

    This article presents the results of a research conducted on Lower Noteć river for the application of geographic information system (GIS) tools. The study consisted of longitudinal profile soundings of navigable route combined with statistical analysis of water levels. GIS software - ArcMap v. 10.0 was used to perform analysis of changes in waterway depth depending on hydrological conditions. A mileage of waterway sections was specified depending on whether they met or did not meet classification requirements in accordance with Polish law. The application of spatial data of Lower Noteć river developed for the purpose of the article is presented. Conducted analyses and obtained results demonstrate the importance of GIS tools in inland navigation studies.

  10. Positive and negative associations between bacterial species in dental root canals.

    Science.gov (United States)

    Gomes, B P; Drucker, D B; Lilley, J D

    1994-01-01

    Significant associations have been previously reported between certain pairs of bacterial species isolated from human dental root canals. The aim of this study was to examine microbiologically a more extensive series of cases, with particular reference to obligate anaerobes which accounted for 64% of total isolations. A total of 65 different species was isolated and individual root canals yielded a maximum of eleven bacterial species. Highly significant positive associations (p spp. and Prevotella spp., between Peptostreptococcus spp. and P. melaninogenica, between P. micros and Prevotella spp., P. micros and P. melaninogenica and between Prevotella spp. and Eubacterium spp., all with an ODDS ratio of > 9.0. In contrast, negative and highly significant associations (p spp., B. gracilis/F. nucleatum and between B. gracilis/Fusobacterium spp.; all with an ODDS ratio of < 0.5. Some previously published associations were confirmed and some new associations were found, while some negative associations became apparent.

  11. Investigating driver willingness to drive through flooded waterways.

    Science.gov (United States)

    Pearson, Marti; Hamilton, Kyra

    2014-11-01

    Approximately 40% of all drowning deaths involve a motor vehicle. Regardless of its significance as a cause of flood-related mortality, there is continued prevalence of driving through flooded waterways in Australia and worldwide. We aimed to understand the motivational determinates of driving through flooded waterways in low and high-risk scenarios by utilizing an augmented theory of planned behaviour (TPB) with behavioural willingness as the outcome variable as well as the influence of additional predictors; namely perceived risk and past behaviour. Participants (n=174; Mage=27.43, SD=10.76) answered standard TPB-based questions in regards to attitudes, subjective norm, and perceived behavioural control (PBC), as well as additional variables of perceived risk (i.e., perceived susceptibility and perceived severity) and past behaviour. Support was found for the augmented TPB as attitude, subjective norm, and PBC predicted behavioural willingness. Support was also found for perceived severity in the high-risk but not the low-risk scenario. No support was found for perceived susceptibility. Past behaviour emerged as a significant predictor of willingness in the low and high-risk scenario. The findings provide support for an augmented TPB in understanding individuals' willingness to drive through flooded waterways, suggesting that a multi-strategy approach may be critical in attempts to reduce the incidence of such risky driving behaviour. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Surgical Procedures for External Auditory Canal Carcinoma and the Preservation of Postoperative Hearing

    Directory of Open Access Journals (Sweden)

    Hiroshi Hoshikawa

    2012-01-01

    Full Text Available Carcinoma of the external auditory canal (EAC is an unusual head and neck malignancy. The pathophysiology of these tumors is different from other skin lesions because of their anatomical and functional characteristics. Early-stage carcinoma of the EAC can be generally cured by surgical treatment, and reconstruction of the EAC with a tympanoplasty can help to retain hearing, thus improving the patients’ quality of life. In this study, we present two cases of early-stage carcinoma of the EAC treated by canal reconstruction using skin grafts after lateral temporal bone resection. A rolled-up skin graft with a temporal muscle flap was useful for keeping the form and maintaining the postoperative hearing. An adequate size of the skin graft and blood supply to the graft bed are important for achieving a successful operation.

  13. Recent Positioning Techniques for Efficient Port Operations and Development of Suez Canal Corridor

    Directory of Open Access Journals (Sweden)

    Ahmed Elhattab

    2016-12-01

    Full Text Available The current developments in positioning techniques and communication technology have great impact on both construction and operations of ports. The majority of positioning systems for marine traffic are satellite based such as GPS. Virtual Reference Station is one of the recent high precision techniques for GNSS positioning which can be used for smart and efficient port.The advantages of using virtual reference station technique in different port operation and construction have been discussed in this paper. To apply this technique in Suez Canal corridor zone, a design of Continuously Operating Reference Station network has been proposed. This network can be utilized during different construction and operations phases of Suez Canal Corridor project.  

  14. Distribution and abundance of the West Indian manatee (Trichechus manatus) in the Panama Canal

    OpenAIRE

    Vianna, Juliana; Muschett, Giselle

    2015-01-01

    The present study was carried out to assess the distribution and current status of the West-Indian manatee Trichechus manatus, in Lake Gatun, the main body of water in the Panama Canal. We used four different methodologies: interviews, revision review of documents, aquatic and aerial surveys. Forty-four interviews carried out between March and July 2007 revealed 59 manatee sightings. Official documents revealed 19 manatee deaths between 1995 and 2008, while three aerial surveys yielded a tota...

  15. Esophageal carcinoma extending into the spinal canal - case report and review of the literature

    International Nuclear Information System (INIS)

    Urban, Linei A.B.D.; Rogacheski, Enio; Ledesma, Jorge A.; Zaparolli, Mauricio; Duarte, Maria Cecilia B.; Sakamoto, Danielle G.

    2002-01-01

    The authors report the case of a 62-year-old male with a 4 month history of weight loss and a 2 day complaint of weakness and paraesthesia on the lower limbs. A computed tomography myelogram revealed a mass in the posterior mediastinum associated with destruction of the vertebral body, spinal canal extension and irregular esophageal wall thickening. The patient was later submitted to a barium esophagogram that showed an irregular filling defect. A biopsy confirmed the presence of a squamous cell carcinoma. This is the first report in the Latin-American literature (Lilacs) of a patient with an esophageal carcinoma with spinal canal extension and spinal cord compression syndrome at initial presentation. (author)

  16. On the waterfront : water distribution, technology and agrarian change in a South Indian canal irrigation system

    OpenAIRE

    Mollinga, P.P.

    1998-01-01

    This book discusses water distribution in the Tungabhadra Left Bank Canal irrigation system in Raichur district, Karnataka, India. The system is located in interior South India, where rainfall is limited (approximately 600 mm annually) and extremely variable. The region suffered from failed harvests and famines in the past. A large scale irrigation system was constructed to solve these problems. The system is operational since 1953 and was completed in 1968. The area to be irrigated ...

  17. The prevalence of mandibular retromolar canals on cone beam computed tomography and its clinical repercussions

    OpenAIRE

    FREITAS, George Borja de; FREITAS E SILVA, Alessandra de; MANHÃES JÚNIOR, Luiz Roberto Coutinho

    2017-01-01

    Abstract Introduction Knowledge on the normal morphology of the human mandible and its possible anatomical variations are of fundamental importance in dental practice, especially in the areas of surgery and implantodontics. The retromolar region is delimited by the anterior margin of the ramus of the mandible, the temporal crest and the distal surface of the last lower molar. In this area, a retromolar canal may be observed emerging through the retromolar foramen. Objective This study aims ...

  18. Scaling of Haversian canal surface area to secondary osteon bone volume in ribs and limb bones.

    Science.gov (United States)

    Skedros, John G; Knight, Alex N; Clark, Gunnar C; Crowder, Christian M; Dominguez, Victoria M; Qiu, Shijing; Mulhern, Dawn M; Donahue, Seth W; Busse, Björn; Hulsey, Brannon I; Zedda, Marco; Sorenson, Scott M

    2013-06-01

    Studies of secondary osteons in ribs have provided a great deal of what is known about remodeling dynamics. Compared with limb bones, ribs are metabolically more active and sensitive to hormonal changes, and receive frequent low-strain loading. Optimization for calcium exchange in rib osteons might be achieved without incurring a significant reduction in safety factor by disproportionally increasing central canal size with increased osteon size (positive allometry). By contrast, greater mechanical loads on limb bones might favor reducing deleterious consequences of intracortical porosity by decreasing osteon canal size with increased osteon size (negative allometry). Evidence of this metabolic/mechanical dichotomy between ribs and limb bones was sought by examining relationships between Haversian canal surface area (BS, osteon Haversian canal perimeter, HC.Pm) and bone volume (BV, osteonal wall area, B.Ar) in a broad size range of mature (quiescent) osteons from adult human limb bones and ribs (modern and medieval) and various adult and subadult non-human limb bones and ribs. Reduced major axis (RMA) and least-squares (LS) regressions of HC.Pm/B.Ar data show that rib and limb osteons cannot be distinguished by dimensional allometry of these parameters. Although four of the five rib groups showed positive allometry in terms of the RMA slopes, nearly 50% of the adult limb bone groups also showed positive allometry when negative allometry was expected. Consequently, our results fail to provide clear evidence that BS/BV scaling reflects a rib versus limb bone dichotomy whereby calcium exchange might be preferentially enhanced in rib osteons. Copyright © 2013 Wiley Periodicals, Inc.

  19. Anterior semicircular canal benign paroxysmal positional vertigo and positional downbeating nystagmus.

    Science.gov (United States)

    Lopez-Escamez, Jose A; Molina, Maria I; Gamiz, Maria J

    2006-01-01

    The aim of this study was to describe the clinical features and video-oculographic findings in patients with anterior semicircular canal benign paroxysmal positional vertigo (BPPV). This is a prospective case series. The study was set at an outpatient clinic in a general hospital. Fourteen individuals with symptoms of BPPV and positional downbeating nystagmus (pDBN) were included in the study. The diagnosis was based on a history of brief episodes of vertigo and the presence of pDBN confirmed in the video-oculographic examination during Dix-Hallpike test (DH) or head-hanging maneuver. Patients were treated by particle repositioning maneuver and the effectiveness was evaluated at 7, 30, and 180 days posttreatment. The treatment was repeated up to 4 times if pDBN was persistent. The main outcome measure is the number of patients without pDBN at 30 and 180 days. Video-oculography showed a predominant pDBN in response to DH. Of the 14 patients, 7 had arterial hypertension, and 5 of 14 cases presented abnormalities on the caloric test. Horizontal spontaneous nystagmus was found in 3 of 14 individuals. Positional nystagmus at different positional test was observed in 5 of 14 individuals, suggesting the involvement of several canals. Of the 14 patients, 10 (71%) did not present vertigo, and the positional tests were negative at 30 days. However, 3 cases presented a positive DH with persistence of BPPV episodes and pDBN at 30 days, and another developed a contralateral posterior canal affectation. One of the patients maintained a persistent pDBN at 180 days despite the repeated maneuvers. Video-oculography demonstrates that anterior canal BPPV is characterized by a predominant downbeating nystagmus in response to DH. These individuals may show alterations in the vestibular caloric, and they can have multicanal affectation.

  20. Evaluation of radiotherapy and chemoradiotherapy for anal canal epidermoid cancer in our center

    International Nuclear Information System (INIS)

    Obara, Kunihiko; Sahara, Rikisaburo; Yamana, Tetsuro; Okamoto, Kinya; Takahashi, Tomoko; Furukawa, Satomi; Okada, Daisuke; Kaneko, Yasushi; Matsumoto, Atsuo

    2008-01-01

    The efficacy and safety of radiotherapy (RT) and chemoradiotherapy (CRT) for anal canal epidermoid cancer were evaluated. Twenty-four patients with anal canal epidermoid cancer were treated in our center between 1988 and 2006, consisting of 13 patients treated by RT and 11 by CRT. In these patients, the efficacy and safety of RT and CRT were evaluated in terms of adverse events, 5-year local control rates, 5-year disease-free survival rates, and 5-year survival rates. No grade 3 or higher adverse events were noted in patients receiving RT. In contrast, anorexia, diarrhea, neutropenia, and anemia were observed in 33.3%, 10%, 33.3%, and 10%, respectively, of the patients receiving CRT. The anal preserving rate, 5-year local control rate, 5-year disease-free survival rate, and 5-year survival rate were 66.7%, 73%, 77.5%, and 88.4%, respectively. RT and CRT for anal canal epidermoid cancer should be first-line treatments because of their safety and efficacy. (author)

  1. Spontaneous CSF-leaks and meningoencephaloceles in sphenoid sinus by persisting Sternberg's canal.

    Science.gov (United States)

    Tomazic, Peter Valentin; Stammberger, Heinz

    2009-12-01

    Cerebrospinal fluid (CSF) leaks and meningoencephaloceles of the lateral recess of sphenoid sinuses are rare findings. A congenital bony defect in the lateral wall of sphenoid sinus called Sternberg's canal could be the origin of these lesions. Their endoscopic transnasal management is challenging though less traumatic than transcranial approaches. The aim of this study was to define Sternberg's canal as a potential source for these rare lesions and to describe their endoscopic endonasal management. In a retrospective analysis clinical charts of 27 patients with CSF-leaks and / or meningoencephaloceles operated between March 2002 and October 2008 at the University ENT-hospital Graz have been reviewed. All patients were treated by an endoscopic endonasal approach. Five patients (4 female / 1 male) were identified with spontaneous CSF-leaks from sphenoid sinus and meningoencephaloceles. In all five cases, Sternberg's canal was the site of leakage, with the bony and dural defects always located laterally between the maxillary and Vidian nerves. Mean age was 51.2 years and mean body mass index (BMI) was 31.9 kg/m2. All patients were operated using a multilayer closure technique. Two patients had recurrences after 12 days and 7 months, respectively, managed by endoscopic revision surgery resulting in a 100% closure rate after one revision (mean follow-up: 6.5 months). Persisting Sternberg's canal can be the source of spontaneous CSF-leaks and meningoencephaloceles in the lateral recess of sphenoid sinus especially when associated with extensive pneumatisation. Endoscopic management is technically challenging, nevertheless its advantages are a good view of the surgical field while being less traumatic than transcranial approaches.

  2. Effect of final irrigation protocols on microhardness reduction and erosion of root canal dentin

    Directory of Open Access Journals (Sweden)

    Flávia Emi Razera BALDASSO

    2017-05-01

    Full Text Available Abstract This study aimed to evaluate the effect of final irrigation protocols on microhardness reduction and erosion of root canal dentin. Sixty root canals from mandibular incisors were instrumented and randomly divided into six groups (n = 10 according to the irrigant used: QMiX, 17% EDTA, 10% citric acid (CA, 1% peracetic acid (PA, 2.5% NaOCl (solution control, and distilled water (negative control. The chelating solutions were used to irrigate the canal followed by 2.5% NaOCl as a final flush. After the irrigation protocols, all specimens were rinsed with 10 mL of distilled water to remove any residue of the chemical solutions. Before and after the final irrigation protocols, dentin microhardness was measured with a Knoop indenter. Three indentations were made at 100 µm and 500 µm from the root canal lumen. Afterwards, the specimens were prepared for scanning electron microscopic analysis and the amount of dentin erosion was examined. Wilcoxon and Kruskal-Wallis tests were used to analyze the results with a significance level set at 5%. At 100 µm, all protocols significantly reduced dentin microhardness (p < .05, while at 500 µm, this effect was detected only in the EDTA and QMiX groups (p < .05. CA was the irrigant that caused more extensive erosion in dentinal tubules, followed by PA and EDTA. QMiX opened dentinal tubules, but did not cause dentin erosion. Results suggest that QMiX and 17% EDTA reduced dentin microhardness at a greater depth. Additionally, QMiX did not cause dentin erosion.

  3. Canalization and control in automata networks: body segmentation in Drosophila melanogaster.

    Directory of Open Access Journals (Sweden)

    Manuel Marques-Pita

    Full Text Available We present schema redescription as a methodology to characterize canalization in automata networks used to model biochemical regulation and signalling. In our formulation, canalization becomes synonymous with redundancy present in the logic of automata. This results in straightforward measures to quantify canalization in an automaton (micro-level, which is in turn integrated into a highly scalable framework to characterize the collective dynamics of large-scale automata networks (macro-level. This way, our approach provides a method to link micro- to macro-level dynamics--a crux of complexity. Several new results ensue from this methodology: uncovering of dynamical modularity (modules in the dynamics rather than in the structure of networks, identification of minimal conditions and critical nodes to control the convergence to attractors, simulation of dynamical behaviour from incomplete information about initial conditions, and measures of macro-level canalization and robustness to perturbations. We exemplify our methodology with a well-known model of the intra- and inter cellular genetic regulation of body segmentation in Drosophila melanogaster. We use this model to show that our analysis does not contradict any previous findings. But we also obtain new knowledge about its behaviour: a better understanding of the size of its wild-type attractor basin (larger than previously thought, the identification of novel minimal conditions and critical nodes that control wild-type behaviour, and the resilience of these to stochastic interventions. Our methodology is applicable to any complex network that can be modelled using automata, but we focus on biochemical regulation and signalling, towards a better understanding of the (decentralized control that orchestrates cellular activity--with the ultimate goal of explaining how do cells and tissues 'compute'.

  4. Canalization and control in automata networks: body segmentation in Drosophila melanogaster.

    Science.gov (United States)

    Marques-Pita, Manuel; Rocha, Luis M

    2013-01-01

    We present schema redescription as a methodology to characterize canalization in automata networks used to model biochemical regulation and signalling. In our formulation, canalization becomes synonymous with redundancy present in the logic of automata. This results in straightforward measures to quantify canalization in an automaton (micro-level), which is in turn integrated into a highly scalable framework to characterize the collective dynamics of large-scale automata networks (macro-level). This way, our approach provides a method to link micro- to macro-level dynamics--a crux of complexity. Several new results ensue from this methodology: uncovering of dynamical modularity (modules in the dynamics rather than in the structure of networks), identification of minimal conditions and critical nodes to control the convergence to attractors, simulation of dynamical behaviour from incomplete information about initial conditions, and measures of macro-level canalization and robustness to perturbations. We exemplify our methodology with a well-known model of the intra- and inter cellular genetic regulation of body segmentation in Drosophila melanogaster. We use this model to show that our analysis does not contradict any previous findings. But we also obtain new knowledge about its behaviour: a better understanding of the size of its wild-type attractor basin (larger than previously thought), the identification of novel minimal conditions and critical nodes that control wild-type behaviour, and the resilience of these to stochastic interventions. Our methodology is applicable to any complex network that can be modelled using automata, but we focus on biochemical regulation and signalling, towards a better understanding of the (decentralized) control that orchestrates cellular activity--with the ultimate goal of explaining how do cells and tissues 'compute'.

  5. Diode Laser and Calcium Hydroxide for Elimination of Enterococcus Faecalis in Root Canal

    Directory of Open Access Journals (Sweden)

    Neda Naghavi

    2014-06-01

    Full Text Available Introduction: The ultimate goal of endodontic treatment is to eliminate the bacterial infection in the root canal system. While mechanical debridement combined with chemical irrigation removes the bulk of microorganisms, residual bacteria are readily detectable in approximately one-half of teeth just prior to obturation. Laser light can be used to destroy bacteria. This in vitro study was performed to evaluate the effect of diode laser and calcium hydroxide on mono-infected dental canals.Methods: Fifty five single-rooted human premolars were prepared and contaminated with Enterococcus faecalis. After three weeks of incubation, the samples were divided into three experimental groups (n = 15 and two control groups (n = 5. In the first and second groups, the teeth were rinsed for 5 min with either sterile saline or 5.25% NaOCl and irradiated with a 810-nm diode laser at 1.5 W output for 5 × 4s. In the third group, the teeth were rinsed with 5.25% NaOCl and then Ca(OH2 paste was inserted in the canals for 1 week. Intracanal bacterial sampling was done and the samples were plated to determine the CFU count. Results: 5.25% NaOCl plus laser was as effective as calcium hydroxide and significantly more effective than sterile saline (P>0.05 in elimination of E. faecalis. Complete elimination of E. faecalis was seen only for the one week calcium hydroxide treatment. Conclusion: Combination therapy with NaOCl irrigation and diode laser irradiation can be recommended as an effective treatment option for elimination of E. faecalis from the root canal system.

  6. Prospective cohort comparison of bioactive glass implants and conchal cartilage in reconstruction of the posterior canal wall during tympanomastoidectomy

    NARCIS (Netherlands)

    Abramovich, S.; Hannan, S. A.; Huins, C. T.; Georgalas, C.; McGuinness, J.; Vats, A.; Thompson, I.

    2008-01-01

    OBJECTIVE: To compare the effectiveness of bioactive glass implants and conchal cartilage in reconstructing the posterior canal wall during tympanomastoidectomy. STUDY DESIGN: Prospective cohort clinical study. SETTING: Teaching hospital. PATIENTS: Patients with clinically diagnosed chronic

  7. Pre-operative assessment of relationship between inferior dental nerve canal and mandibular impacted third molar in Saudi population

    Directory of Open Access Journals (Sweden)

    S. Shujaat

    2014-07-01

    Conclusions: Our sample population most commonly exhibited horizontally angulated class I position B impactions of the mandible. The position of the ID canal significantly influenced the type of impaction and bone contact.

  8. Multivariate analysis of the cleaning efficacy of different final irrigation techniques in the canal and isthmus of mandibular posterior teeth

    Directory of Open Access Journals (Sweden)

    Yeon-Jee Yoo

    2013-08-01

    Full Text Available Objectives The aim of this study was to compare the cleaning efficacy of different final irrigation regimens in canal and isthmus of mandibular molars, and to evaluate the influence of related variables on cleaning efficacy of the irrigation systems. Materials and Methods Mesial root canals from 60 mandibular molars were prepared and divided into 4 experimental groups according to the final irrigation technique: Group C, syringe irrigation; Group U, ultrasonics activation; Group SC, VPro StreamClean irrigation; Group EV, EndoVac irrigation. Cross-sections at 1, 3 and 5 mm levels from the apex were examined to calculate remaining debris area in the canal and isthmus spaces. Statistical analysis was completed by using Kruskal-Wallis test and Mann-Whitney U test for comparison among groups, and multivariate linear analysis to identify the significant variables (regular replenishment of irrigant, vapor lock management, and ultrasonic activation of irrigant affecting the cleaning efficacy of the experimental groups. Results Group SC and EV showed significantly higher canal cleanliness values than group C and U at 1 mm level (p < 0.05, and higher isthmus cleanliness values than group U at 3 mm and all levels of group C (p < 0.05. Multivariate linear regression analysis demonstrated that all variables had independent positive correlation at 1 mm level of canal and at all levels of isthmus with statistical significances. Conclusions Both VPro StreamClean and EndoVac system showed favorable result as final irrigation regimens for cleaning debris in the complicated root canal system having curved canal and/or isthmus. The debridement of the isthmi significantly depends on the variables rather than the canals.

  9. Characteristics, diagnosis and treatment of hypoglossal canal dural arteriovenous fistula: report of nine cases

    Energy Technology Data Exchange (ETDEWEB)

    Manabe, Shinji; Satoh, Koichi; Matsubara, Shunji; Satomi, Junichiro; Hanaoka, Mami; Nagahiro, Shinji [University of Tokushima, Department of Neurosurgery, Tokushima (Japan)

    2008-08-15

    We report the characteristics, diagnosis and treatment of dural arteriovenous fistula (DAVF) of the hypoglossal canal in nine patients with this relatively rare vascular disorder. Of 248 patients with intracranial DAVFs managed at our institution, nine patients (3.6%; four men, five women; mean age 62 years) were diagnosed with hypoglossal canal DAVF. We investigated patient characteristics with respect to clinical symptoms, neuroradiological findings, efficacy and complications related to endovascular treatment. Seven patients had experienced head injury. All patients presented with pulsatile tinnitus. One patient displayed ipsilateral hypoglossal nerve palsy before treatment. MR angiography showed a 'magic wand' appearance between the affected hypoglossal canal and the internal jugular vein in four patients. Angiography demonstrated an AV fistula on the medial aspect of the superior jugular bulb, mostly arising from the bilateral occipital, ascending pharyngeal and vertebral arteries with drainage to the internal jugular vein via the anterior condylar vein. Contralateral carotid injection accurately clarified the shunting point. Five patients underwent endovascular treatment: transarterial embolization (TAE; n=2), transvenous embolization (TVE; n=2), and TAE/TVE (n=1). Complete shunt obliteration was achieved in four patients and shunt reduction in one. The remaining four patients were treated conservatively and the shunt had disappeared at follow-up. Postoperative hypoglossal nerve palsy occurred in one patient after TVE, possibly due to coil overpacking. The incidence of hypoglossal canal DAVF was not very low in our series. Contralateral carotid injection is an essential examination to provide an accurate diagnosis. TVE should be considered when access is available, although TAE is also appropriate for shunt reduction. (orig.)

  10. Extrusion of Debris from Primary Molar Root Canals following Instrumentation with Traditional and New File Systems.

    Science.gov (United States)

    Thakur, Bhagyashree; Pawar, Ajinkya M; Kfir, Anda; Neelakantan, Prasanna

    2017-11-01

    To assess the amount of debris extruded apically during instrumentation of distal canals of extracted primary molars by three instrument systems [ProTaper Universal (PTU), ProTaper NEXT (PTN), and self-adjusting file (SAF)] compared with conventional stainless steel hand K-files (HF, control). Primary mandibular molars (n = 120) with a single distal canal were selected and randomly divided into four groups (n = 30) for root canal instrumentation using group I, HF (to size 0.30/0.02 taper), group II, PTU (to size F3), group III, PTN (to size X3), and group IV, SAF. Debris extruded during instrumentation was collected in preweighed Eppendorf tubes, stored in an incubator at 70°C for 5 days and then weighed. Statistical analysis was performed by one-way analysis of variance (ANOVA), followed by Turkey's post hoc test (p = 0.05). All the groups resulted in extrusion of debris. There was statistically significant difference (p < 0.001) in the debris extrusion between the three groups: HF (0.00133 ± 0.00012), PTU (0.00109 ± 0.00005), PTN (0.00052 ± 0.00008), and SAF (0.00026 ± 0.00004). Instrumentation with SAF resulted in the least debris extrusion when used for shaping root canals of primary molar teeth. Debris extrusion in primary teeth poses an adverse effect on the stem cells and may also alter the permanent dental germ. Debris extrusion is rarely reported for primary teeth and it is important for the clinician to know which endodontic instrumentation leads to less extrusion of debris.

  11. Characteristics, diagnosis and treatment of hypoglossal canal dural arteriovenous fistula: report of nine cases

    Energy Technology Data Exchange (ETDEWEB)

    Manabe, Shinji; Satoh, Koichi; Matsubara, Shunji; Satomi, Junichiro; Hanaoka, Mami; Nagahiro, Shinji [University of Tokushima, Department of Neurosurgery, Tokushima (Japan)

    2008-08-15

    We report the characteristics, diagnosis and treatment of dural arteriovenous fistula (DAVF) of the hypoglossal canal in nine patients with this relatively rare vascular disorder. Of 248 patients with intracranial DAVFs managed at our institution, nine patients (3.6%; four men, five women; mean age 62 years) were diagnosed with hypoglossal canal DAVF. We investigated patient characteristics with respect to clinical symptoms, neuroradiological findings, efficacy and complications related to endovascular treatment. Seven patients had experienced head injury. All patients presented with pulsatile tinnitus. One patient displayed ipsilateral hypoglossal nerve palsy before treatment. MR angiography showed a 'magic wand' appearance between the affected hypoglossal canal and the internal jugular vein in four patients. Angiography demonstrated an AV fistula on the medial aspect of the superior jugular bulb, mostly arising from the bilateral occipital, ascending pharyngeal and vertebral arteries with drainage to the internal jugular vein via the anterior condylar vein. Contralateral carotid injection accurately clarified the shunting point. Five patients underwent endovascular treatment: transarterial embolization (TAE; n=2), transvenous embolization (TVE; n=2), and TAE/TVE (n=1). Complete shunt obliteration was achieved in four patients and shunt reduction in one. The remaining four patients were treated conservatively and the shunt had disappeared at follow-up. Postoperative hypoglossal nerve palsy occurred in one patient after TVE, possibly due to coil overpacking. The incidence of hypoglossal canal DAVF was not very low in our series. Contralateral carotid injection is an essential examination to provide an accurate diagnosis. TVE should be considered when access is available, although TAE is also appropriate for shunt reduction. (orig.)

  12. Characteristics, diagnosis and treatment of hypoglossal canal dural arteriovenous fistula: report of nine cases

    International Nuclear Information System (INIS)

    Manabe, Shinji; Satoh, Koichi; Matsubara, Shunji; Satomi, Junichiro; Hanaoka, Mami; Nagahiro, Shinji

    2008-01-01

    We report the characteristics, diagnosis and treatment of dural arteriovenous fistula (DAVF) of the hypoglossal canal in nine patients with this relatively rare vascular disorder. Of 248 patients with intracranial DAVFs managed at our institution, nine patients (3.6%; four men, five women; mean age 62 years) were diagnosed with hypoglossal canal DAVF. We investigated patient characteristics with respect to clinical symptoms, neuroradiological findings, efficacy and complications related to endovascular treatment. Seven patients had experienced head injury. All patients presented with pulsatile tinnitus. One patient displayed ipsilateral hypoglossal nerve palsy before treatment. MR angiography showed a ''magic wand'' appearance between the affected hypoglossal canal and the internal jugular vein in four patients. Angiography demonstrated an AV fistula on the medial aspect of the superior jugular bulb, mostly arising from the bilateral occipital, ascending pharyngeal and vertebral arteries with drainage to the internal jugular vein via the anterior condylar vein. Contralateral carotid injection accurately clarified the shunting point. Five patients underwent endovascular treatment: transarterial embolization (TAE; n=2), transvenous embolization (TVE; n=2), and TAE/TVE (n=1). Complete shunt obliteration was achieved in four patients and shunt reduction in one. The remaining four patients were treated conservatively and the shunt had disappeared at follow-up. Postoperative hypoglossal nerve palsy occurred in one patient after TVE, possibly due to coil overpacking. The incidence of hypoglossal canal DAVF was not very low in our series. Contralateral carotid injection is an essential examination to provide an accurate diagnosis. TVE should be considered when access is available, although TAE is also appropriate for shunt reduction. (orig.)

  13. Isolation and identification of Enterococcus faecalis from necrotic root canals using multiplex PCR.

    Science.gov (United States)

    Mahmoudpour, Ali; Rahimi, Saeed; Sina, Mahmood; Soroush, Mohammad H; Shahi, Shahriar; Shahisa, Shahriar; Asl-Aminabadi, Naser

    2007-09-01

    This study was designed to survey the incidence of Enterococcus faecalis infection in symptomatic and asymptomatic root canals of necrotic teeth using PCR and to isolate the bacterium for further screening. Sixty patients categorized according to their clinical symptoms were used for sampling by insertion of paper points into the root canals and absorbing all the fluids present within them. The samples were incubated in 1.0 ml 2xYT (containing 16 g bacto tryptone, 10 g yeast extract and 5.0 g NaCl per liter) for 24 h at 37 degrees C without aeration prior to multiplex PCR analysis. To assist the isolation of E. faecalis, sub-samples were further grown in the same medium supplemented with 6.5% NaCl and back-inoculated into bile esculin. Using multiple cultivation-dependent and PCR analyses, 6 cases (10%) of E. faecalis were identified. Four isolates were obtained from asymptomatic cases of chronic apical periodontitis, and the other two were associated with phoenix abscess and acute apical abscess, respectively. No E. faecalis infection was found in 5 patients with acute apical periodontitis or in 9 with chronic suppurative periodontitis. Our results indicate that there is no significant difference in the incidence of E. faecalis between symptomatic and asymptomatic necrotic dental root canals (P > 0.05).

  14. Dynamics of fecal indicator bacteria, bacterial pathogen genes, and organic wastewater contaminants in the Little Calumet River: Portage Burns Waterway, Indiana

    Science.gov (United States)

    Haack, Sheridan K.; Duris, Joseph W.

    2013-01-01

    Little information exists on the co-occurrence of fecal indicator bacteria (FIB), bacterial pathogens, and organic wastewater-associated chemicals (OWCs) within Great Lakes tributaries. Fifteen watershed sites and one beach site adjacent to the Little Calumet River–Portage Burns Waterway (LCRPBW) on Lake Michigan were tested on four dates for pH, dissolved oxygen, specific conductance, chloride, color, ammonia- and nitrate-nitrogen, soluble phosphorus, sulfate, turbidity, and atrazine; for concentrations of FIB; and for genes indicating the presence of human-pathogenic enterococci (ENT) and of Shiga-toxin producing Escherichia coli (EC) from various animal sources. Nineteen samples were also tested for 60 OWCs. Half of the watershed samples met EC recreational water quality standards; none met ENT standards. Human-wastewater-associated OWC detections were correlated with human-influence indicators such as population/km2, chloride concentrations, and the presence of WWTP effluents, but EC and ENT concentrations were not. Bacterial pathogen genes indicated rural human and several potential animal sources. OWCs of human or ecosystem health concern (musk fragrances AHTN and HHCB, alkylphenols, carbamazepine) and 3 bacterial pathogen genes were detected at the mouth of the LCRPBW, but no such OWCs and only 1 pathogen gene were detected at the beach. The LCRPBW has significant potential to deliver FIB, potential bacterial pathogens, and OWCs of human or ecosystem health concern to the nearshore of Lake Michigan, under conditions enhancing nearshore transport of the river plume. Nearshore mixing of lake and river water, and the lack of relationship between OWCs and FIB or pathogen genes, pose numerous challenges for watershed and nearshore assessment and remediation.

  15. Comparing heavy metals accumulation potential in natural vegetation and soil adjoining wastewater canal

    International Nuclear Information System (INIS)

    Aurangzeb, N.; Irshad, M.; Hussain, F.; Mahmood, Q.

    2011-01-01

    Heavy metal (HM) pollution of waters, soils and vegetation is a major ecological problem that needs to be investigated. The present study involved the collection of soil samples and natural vegetations (Tribilas terristris, Lepia nodiflora, Amaranthus viridis, Heliotropium euoropeum, Coronopis didymus, Cynodon ductylon, Chenopodium murale and Eclipta alba) from the vicinity of wastewater canal and subsequent analysis for their HM concentrations. Results showed that HM concentrations varied within the species of vegetation and type of metal analyzed. The order of vegetation for metal concentrations was A. viridis > E. alba > H. euoropeum > L. nodiflora > C. murale > C. didymus > C. ductylon > T. terristris. Metals prevailed in plants in the decreasing order of Fe > Mn > Zn > Pb > Cr > Cu > Cd, irrespective of the vegetation. Metal prevalence in soils was in the order of Fe > Mn > Cd > Cr > Pb > Zn > Cu. Samples near canal were found with higher level of Mn, Pb and Zn as compared to soil away from canal water. Distant sampling gave higher accumulation of Cd, Cr, Cu and Fe as compared to the soil nearby wastewater. The analyzed species of HM in the soils and plants may indicate the variability of their composition in wastewater. (author)

  16. Determination and partitioning of metals in sediments along the Suez Canal by sequential extraction

    Science.gov (United States)

    Abd El-Azim, H.; El-Moselhy, Kh. M.

    2005-06-01

    The application of sequential extraction technique was used to determine the chemical association of heavy metals in five different chemical phases (exchangeable F1, bound to carbonate F2, bound to Fe-Mn oxides F3, bound to organic matter F4 and residual F5) for sediment samples collected from the Suez Canal. From the obtained data, it can be seen that the surplus of metal contaminants introduced into the sediment from sources usually exists in relatively unstable chemical forms. A high proportion of the studied metals remained in the residual fraction. Most of remaining portion of metals was bound to ferromanganese oxides fraction. The low concentrations of metals in the exchangeable fraction indicated that the sediments of Suez Canal were relatively unpolluted.

  17. MR imaging of spine and spinal canal neoplasms: value of Gd-DTPA contrast enhancement

    International Nuclear Information System (INIS)

    Paprzycki, W.; Gradzki, J.; Sosnowski, P.; Stajgis, M.

    1994-01-01

    Value of Gadolinium-DTPA contrast enhancement in diagnosis of neoplastic diseases of spinal canal was estimated on the basis of retrospective analysis of MR examinations performed in 75 patients. The analyzed material consisted of 15 cases of intramedullary tumors (group 1.), 38 of subdural extramedullary (group 2.) and 22 extradural ones (group 3.). Contrast enhanced MR contributed significant information to the final diagnosis in all groups. The utmost significance of Gd-DTPA contrast enhancement was ascertained in group 1. Authors conclude that contrast enhancement with Gd-DTPA is indispensable in all these cases of spinal canal neoplasms, where non-contrast MR did not reveal pathologic changes in optimal manner. (author)

  18. The use of plastic models for teaching root canal cleansing and shaping

    Directory of Open Access Journals (Sweden)

    Eftekhar B

    2004-02-01

    Full Text Available The use of root canal models in endodontics education is of high importance. So, in this article"na new method is presented that the students can produce these models with simple and low cost"ninstruments."nThese plastic models are made of polyester which is low cost, available and has the approximate cutting"nproperties of dentin. The best molds were disposable syringes due to their low cost, availability and"nproducing smooth surfaces on polyester models. A spreader with desired curve and tapering is used for"nproducing canals. Rockwell A hardness coefficient of polyester is "33", which is near dentin "31" and"nforeign made models "35.5". Since these polyester models can tolerate up to 280°C and have acceptable"nresistance to chloroform, all root canal therapy techniques such as vertical condensation and retreatments"nare practicable. Their transparency encourage the students to work on them. As a result, the use of these"nmodels is recommended for endodontics training.

  19. Ex vivo evaluation of coronal and apical microbial leakage of root canal - Filled with gutta-percha or Resilon/Epiphany root canal filling material

    Directory of Open Access Journals (Sweden)

    de Almeida-Gomes Fabio

    2010-01-01

    Full Text Available Objective: This ex vivo study compared coronal and apical microleakage of root canals filled with Resilon/Epiphany (RE or gutta-percha/Grossman sealer (GP, using either lateral condensation (LC or System B (SB technique. Materials and Methods: Specimens in eight experimental groups were obturated using the following materials and techniques: Groups 1 and 3 - GP and LC; groups 2 and 4 - GP and SB; groups 5 and 7 - RE and LC; groups 6 and 8 - RE and SB. Apical and coronal leakages were tested using bacterial methods. For coronal analysis, the number of days required for complete contamination of the root canals was recorded according to observation of the brain heart infusion broth turbidity for 15 weeks. For apical analysis, the teeth were cleaved and the leakage was measured at 30 days. Data were collected for each sample and analyzed statistically with the Chi-square and ANOVA tests. Results: Leakage was found in all groups. The difference between filling materials, obturation techniques, and median time of leakage was not statistically significant for coronal ( P=0.847 and apical ( P=0.5789 leakages. Conclusion: There were no differences between the different filling materials (gutta-percha/Grossman sealer and Resilon/Epiphany and obturation techniques (lateral condensation and system B technique in coronal or apical leakages.

  20. A floating bridge disrupts seaward migration and increases mortality of steelhead smolts in Hood Canal, Washington state.

    Directory of Open Access Journals (Sweden)

    Megan Moore

    Full Text Available Habitat modifications resulting from human transportation and power-generation infrastructure (e.g., roads, dams, bridges can impede movement and alter natural migration patterns of aquatic animal populations, which may negatively affect survival and population viability. Full or partial barriers are especially problematic for migratory species whose life histories hinge on habitat connectivity.The Hood Canal Bridge, a floating structure spanning the northern outlet of Hood Canal in Puget Sound, Washington, extends 3.6 meters underwater and forms a partial barrier for steelhead migrating from Hood Canal to the Pacific Ocean. We used acoustic telemetry to monitor migration behavior and mortality of steelhead smolts passing four receiver arrays and several single receivers within the Hood Canal, Puget Sound, and Strait of Juan de Fuca. Twenty-seven mortality events were detected within the vicinity of the Hood Canal Bridge, while only one mortality was recorded on the other 325 receivers deployed throughout the study area. Migrating steelhead smolts were detected at the Hood Canal Bridge array with greater frequency, on more receivers, and for longer durations than smolts migrating past three comparably configured arrays. Longer migration times and paths are likely to result in a higher density of smolts near the bridge in relation to other sites along the migration route, possibly inducing an aggregative predator response to steelhead smolts.This study provides strong evidence of substantial migration interference and increased mortality risk associated with the Hood Canal Bridge, and may partially explain low early marine survival rates observed in Hood Canal steelhead populations. Understanding where habitat modifications indirectly increase predation pressures on threatened populations helps inform potential approaches to mitigation.

  1. A floating bridge disrupts seaward migration and increases mortality of steelhead smolts in Hood Canal, Washington state.

    Science.gov (United States)

    Moore, Megan; Berejikian, Barry A; Tezak, Eugene P

    2013-01-01

    Habitat modifications resulting from human transportation and power-generation infrastructure (e.g., roads, dams, bridges) can impede movement and alter natural migration patterns of aquatic animal populations, which may negatively affect survival and population viability. Full or partial barriers are especially problematic for migratory species whose life histories hinge on habitat connectivity. The Hood Canal Bridge, a floating structure spanning the northern outlet of Hood Canal in Puget Sound, Washington, extends 3.6 meters underwater and forms a partial barrier for steelhead migrating from Hood Canal to the Pacific Ocean. We used acoustic telemetry to monitor migration behavior and mortality of steelhead smolts passing four receiver arrays and several single receivers within the Hood Canal, Puget Sound, and Strait of Juan de Fuca. Twenty-seven mortality events were detected within the vicinity of the Hood Canal Bridge, while only one mortality was recorded on the other 325 receivers deployed throughout the study area. Migrating steelhead smolts were detected at the Hood Canal Bridge array with greater frequency, on more receivers, and for longer durations than smolts migrating past three comparably configured arrays. Longer migration times and paths are likely to result in a higher density of smolts near the bridge in relation to other sites along the migration route, possibly inducing an aggregative predator response to steelhead smolts. This study provides strong evidence of substantial migration interference and increased mortality risk associated with the Hood Canal Bridge, and may partially explain low early marine survival rates observed in Hood Canal steelhead populations. Understanding where habitat modifications indirectly increase predation pressures on threatened populations helps inform potential approaches to mitigation.

  2. Guided endodontics: accuracy of a novel method for guided access cavity preparation and root canal location.

    Science.gov (United States)

    Zehnder, M S; Connert, T; Weiger, R; Krastl, G; Kühl, S

    2016-10-01

    To present a novel method utilizing 3D printed templates to gain guided access to root canals and to evaluate its accuracy in vitro. Sixty extracted human teeth were placed into six maxillary jaw models. Preoperative CBCT scans were matched with intra-oral scans using the coDiagnostix(™) software. Access cavities, sleeves and templates for guidance were virtually planned. Templates were produced by a 3D printer. After access cavity preparation by two operators, a postoperative CBCT scan was superimposed on the virtual planning. Accuracy was measured by calculating the deviation of planned and prepared cavities in three dimensions and angle. Ninety-five per cent confidence intervals were calculated for both operators. All root canals were accessible after cavity preparation with 'Guided Endodontics'. Deviations of planned and prepared access cavities were low with means ranging from 0.16 to 0.21 mm for different aspects at the base of the bur and 0.17-0.47 mm at the tip of the bur. Mean of angle deviation was 1.81°. Overlapping 95% confidence intervals revealed no significant difference between operators. 'Guided Endodontics' allowed an accurate access cavity preparation up to the apical third of the root utilizing printed templates for guidance. All root canals were accessible after preparation. © 2015 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  3. In vitro evaluation of the root canal cleaning ability of plant extracts and their antimicrobial action

    Directory of Open Access Journals (Sweden)

    Edja Maria Melo de Brito Costa

    2012-06-01

    Full Text Available This in vitro study evaluated both the antimicrobial activity and the root canal cleaning ability of plant extracts used in irrigation solutions. The antimicrobial activities of the aroeira-da-praia (Schinus terebintifolius Raddi and the quixabeira (Syderoxylum obtusifolium Roem & Schult hydroalcoholic extracts, of 2.5% sodium hypochlorite (NaOCl and of 0.12% chlorhexidine (positive control against Enterococcus faecalis were tested with the agar well diffusion method. The level of root canal cleanliness was examined by scanning electron microscopy (SEM. Twenty one single-rooted human teeth were divided into three groups according to the irrigation solution applied: 1 50% aroeira-da-praia; 2 50% quixabeira and 3 a combination of 2.5% sodium hypochlorite + 17% EDTA. All solutions tested demonstrated antimicrobial activity against Enterococcus faecalis. The SEM analysis revealed that higher and lower degrees of surface cleaning were observed, in the three groups, respectively for the coronal and apical thirds, in that quixabeira showed the greatest efficiency in removing the smear layer in the apical third. All the agents tested presented antimicrobial activity against E. faecalis. None, however, was able to completely remove the smear layer of the dentinal surface in the different thirds of the root canal. The results suggest that the analyzed plant extracts may represent a new therapeutic option in the list of alternative agents available for endodontic treatment.

  4. Contamination level in vegetables grown around Peshawar using sewerage and canal water

    International Nuclear Information System (INIS)

    Mahmood, S.

    2001-01-01

    The level of contamination in vegetables grown around Peshawar using sewerage/canal water is reported. The vegetable samples were collected from three representative locations. The results indicated that vegetables grown with sewerage water contained higher levels of Cd, Cu and Pb than those with irrigation water. Maximum amount of Cd was in Qulfa (3.68 mu g/ g) followed by sponge gourd leaves (3.38 mu g/ g) the tomato leaves (93.32 mu g/ g). while Pb in tomato leaves (4.88 mu g / g), Cu content ranged between 2.08 and 7.5 mu g/g in these vegetables. In the vegetables grown with canal water the Cd ranged 0.82 - 2.88 mu g/g, Cu 2.38 mu g /g and Pb 0.84 - 1.88 mu g/ g. The concentration of Fe and P in the vegetables of sewerage water ranged 9.0-25.0 and 5.6-14.8 mg/100g respectively while those grown with canal water 9.0-11.0 mg/ 100 g and 8.4-12.8 mg/ 100 g respectively. (author)

  5. APICAL SEAL BETWEEN ADHESIVE ROOT CANAL OBTURATION SYSTEM AND GUTTA-PERCHA/AH-PLUS SEALER: AN IN VITRO COMPARISON STUDY

    Directory of Open Access Journals (Sweden)

    Girish

    2016-03-01

    Full Text Available BACKGROUND Three dimensional obturation of the root canal is important for success of root canal treatment. Microleakage is one of the reason for root canal failure. Numerous materials have been used for obturation of which Gutta-percha is the most successful with variety of sealers. One of the recent material to further improve root canal treatment success rate is use of Resilon with Epiphany root canal sealer to apply adhesive concepts in to endodontics. An adhesive bond forms between Epiphany sealer, Resilon and dentin, making it monolithic hence less microleakage if any significantly. METHODS 60 single rooted mandibular premolars were dissected at cement enamel junction with diamond disc. Root canals were explored and working length measured using K file. Root canals of all 60 samples were prepared with ProTaper and irrigated with 5% sodium hypochlorite and 17% EDTA solution. Teeth were divided in to group A and B, each having 30 samples. Group A teeth obturated with Resilon Epiphany obturation system and group B with Gutta-percha and AH-plus sealer. All specimens were stored in incubator for 30 days. Clearing process of samples done with Robertson’s technique to make them transparent. All the specimens were immersed in 2% methylene blue dye solution for 7 days. Specimens were then examined under stereomicroscope with 10x magnification to measure dye penetration in mm with image analysis software. The data collected were analysed statistically. RESULTS This study showed that Resilon Epiphany group has a mean leakage of 1.2307, while the Gutta-percha/AH-plus had a mean leakage of 3.6133. There was statistically significant differences between Resilon and Gutta-percha groups. CONCLUSIONS 1. Resilon Epiphany group showed less apical microleakage than Gutta-percha/AH-plus obturation. 2. Based on result obtained it is suggested that Resilon Epiphany can be recommended for root canal obturation.

  6. Identification of dental root canals and their medial line from micro-CT and cone-beam CT records

    Directory of Open Access Journals (Sweden)

    Benyó Balázs

    2012-10-01

    Full Text Available Abstract Background Shape of the dental root canal is highly patient specific. Automated identification methods of the medial line of dental root canals and the reproduction of their 3D shape can be beneficial for planning endodontic interventions as severely curved root canals or multi-rooted teeth may pose treatment challenges. Accurate shape information of the root canals may also be used by manufacturers of endodontic instruments in order to make more efficient clinical tools. Method Novel image processing procedures dedicated to the automated detection of the medial axis of the root canal from dental micro-CT and cone-beam CT records are developed. For micro-CT, the 3D model of the root canal is built up from several hundred parallel cross sections, using image enhancement, histogram based fuzzy c-means clustering, center point detection in the segmented slice, three dimensional inner surface reconstruction, and potential field driven curve skeleton extraction in three dimensions. Cone-beam CT records are processed with image enhancement filters and fuzzy chain based regional segmentation, followed by the reconstruction of the root canal surface and detecting its skeleton via a mesh contraction algorithm. Results The proposed medial line identification and root canal detection algorithms are validated on clinical data sets. 25 micro-CT and 36 cone-beam-CT records are used in the validation procedure. The overall success rate of the automatic dental root canal identification was about 92% in both procedures. The algorithms proved to be accurate enough for endodontic therapy planning. Conclusions Accurate medial line identification and shape detection algorithms of dental root canal have been developed. Different procedures are defined for micro-CT and cone-beam CT records. The automated execution of the subsequent processing steps allows easy application of the algorithms in the dental care. The output data of the image processing procedures

  7. CANAL user's manual

    International Nuclear Information System (INIS)

    Faya, A.; Wolf, L.; Todreas, N.

    1979-11-01

    CANAL is a subchannel computer program for the steady-state and transient thermal hydraulic analysis of BWR fuel rod bundles. The purpose of this manual is to introduce the user into the mechanism of running the code by providing information about the input data and options

  8. Working length changes in curved canals after coronal flaring by using rotary files and hand file: An in vitro study.

    Science.gov (United States)

    Kumar, Rahul; Khambete, Neha; Patil, Suvarna; Hoshing, Upendra; Medha, Ashish; Shetty, Roshan

    2013-09-01

    This in vitro investigation examined the effect of early coronal flaring (CF) and late CF on the working length (WL) in curved root canals. The objective of this study was to determine if canal length is altered as a result of CF in curved canals of molar roots. The conditions compared were combinations of (a) stainless steel hand files using Gates Glidden (G. G.) drills (SS) versus nickel-titanium rotary files (Ni-Ti); and (b) early CF (flaring completed before WL determination) versus late CF (flaring completed after WL determination). Selected were 90 canals of extracted maxillary or mandibular first molars (mesial root of mandibular molars and the mesiobuccal root of the maxillary molars) from three groups. CF was accomplished for the SS group using G. G. drills and for the Ni-Ti group using rotary ProTaper and Hero Shaper files. WL was determined by a digital vernier caliper before CF, immediately after CF, and again after canal preparation. A repeated measures analysis of variance (ANOVA) test and a Tukey's multiple prosthoc test were used for this study. Results indicated that WL decreased for all canals as a result of canal preparation. The mean decrease in WL was significantly greater for the SS group (-0.77 ± 0.42 mm) than for the Ni-Ti groups (-0.33 mm ± 0.44). Less change in WL occurred in all groups when initial WL was determined after CF. WL in curved canals consistently decreases during the course of instrumentation. Clinician should keep this in mind for better treatment outcome.

  9. Horizontal canal benign paroxysmal positional vertigo: diagnosis and treatment of 37 patients

    Directory of Open Access Journals (Sweden)

    Eliana Teixeira Maranhão

    2015-06-01

    Full Text Available Benign paroxysmal positional vertigo (BPPV, the most frequent cause of vertigo is associated with high morbidity in the elderly population. The most common form is linked to debris in the posterior semicircular canal. However, there has been an increasing number of reported BPPV cases involving the horizontal canals. The purpose of this article is to highlight the clinical features, diagnosis, and treatment in 37 patients with horizontal canal BPPV; twenty-six with geotropic nystagmus, and eleven with the apogeotropic form. Treatment consisted of the Gufoni manoeuver in eighteen patients (48.6%, the barbecue 360° maneuver in twelve patients (32.4%, both manoeuvers in four patients (10.8%, both manoeuvers plus head shaking in one patient (2.7%, and the Gufoni maneuver plus head shaking in two patients. Cupulolithiasis patients were asked to sleep in a forced prolonged position. We obtained a complete resolution of vertigo and nystagmus in 30 patients (81.0% on the initial visit.

  10. External auditory canal cholesteatoma and keratosis obturans: the role of imaging in preventing facial nerve injury.

    Science.gov (United States)

    McCoul, Edward D; Hanson, Matthew B

    2011-12-01

    We conducted a retrospective study to compare the clinical characteristics of external auditory canal cholesteatoma (EACC) with those of a similar entity, keratosis obturans (KO). We also sought to identify those aspects of each disease that may lead to complications. We identified 6 patients in each group. Imaging studies were reviewed for evidence of bony erosion and the proximity of disease to vital structures. All 6 patients in the EACC group had their diagnosis confirmed by computed tomography (CT), which demonstrated widening of the bony external auditory canal; 4 of these patients had critical erosion of bone adjacent to the facial nerve. Of the 6 patients with KO, only 2 had undergone CT, and neither exhibited any significant bony erosion or expansion; 1 of them developed osteomyelitis of the temporal bone and adjacent temporomandibular joint. Another patient manifested KO as part of a dermatophytid reaction. The essential component of treatment in all cases of EACC was microscopic debridement of the ear canal. We conclude that EACC may produce significant erosion of bone with exposure of vital structures, including the facial nerve. Because of the clinical similarity of EACC to KO, misdiagnosis is possible. Temporal bone imaging should be obtained prior to attempts at debridement of suspected EACC. Increased awareness of these uncommon conditions is warranted to prompt appropriate investigation and prevent iatrogenic complications such as facial nerve injury.

  11. Politics and soccer in the film through the lens of newsreel Canal 100
    Política e futebol no cinema através das lentes do cinejornal Canal 100

    OpenAIRE

    Paulo Roberto de Azevedo Maia

    2009-01-01

    This document discusses the historical route and the establishment of language of Canal 100, a movie news periodical. The format of the news movie series was studied for a better understanding of its narrative structure and especially the images related to soccer, responsible for the permanence of Canal 100 in the memory of several generations. To this end, we analyzed 42 editions, 55 cin script and collected 26 articles of the printing press, studying the period of 1959 up 1986. O artigo di...

  12. The Citizen Observatory of Radioactivity - Assessment for 2010 of radioactivity survey in the environment at the scale of Normandy (coast and waterways) - Results of measurement of gamma emitters and of Tritium in water

    International Nuclear Information System (INIS)

    2012-01-01

    This document proposes a set of tables containing different information and data regarding measurements of gamma radioactivity and of the presence of tritium made during 2010 in different marine and water environments (algae, sands, sea water, molluscs, sediments, water mosses, vegetal) in different locations: a bay close to the AREVA plant in La Hague, different locations on the Normandy coast, around the AREVA plant in La Hague, and in waterways in Normandy. These tables contain information about the sampling (date, location, quantity, analysed fraction, and so on) and results of measurements of artificial (isotopes of cobalt, ruthenium-rhodium, silver, iodine, caesium, americium, europium) and natural (potassium, beryllium, lead, bismuth, etc.) radionuclides

  13. Duplication of the External Auditory Canal: Two Cases and a Review of the Literature

    Science.gov (United States)

    Goudakos, John K.; Blioskas, Sarantis; Psillas, George; Vital, Victor; Markou, Konstantinos

    2012-01-01

    The objective of the present paper is to describe the clinical presentation, diagnostic process, surgical treatment, and outcome of 2 patients with first branchial cleft anomaly. The first case was an 8-year-old girl presented with an elastic lesion located in the left infra-auricular area, in close relation with the lobule, duplicating the external auditory canal. The magnetic resonance imaging revealed a lesion, appearing as a rather well-circumscribed mass within the left parotid gland and duplicating the ear canal. A superficial parotidectomy was subsequently performed, with total excision of the cyst. The second patient was a 15-year-old girl presented with a congenital fistula of the right lateral neck. At superficial parotidectomy, a total excision of the fistula was performed. During the operation the tract was recorded to lay between the branches of the facial nerve, extending with a blind ending canal parallel to the external acoustic meatus. Conclusively, first branchial cleft anomalies are rare malformations with cervical, parotid, or auricular clinical manifestations. Diagnosis of first branchial cleft lesions is achieved mainly through careful physical examination. Complete surgical excision with wide exposure of the lesion is essential in order to achieve permanent cure and avoid recurrence. PMID:23213587

  14. Duplication of the External Auditory Canal: Two Cases and a Review of the Literature

    Directory of Open Access Journals (Sweden)

    John K. Goudakos

    2012-01-01

    Full Text Available The objective of the present paper is to describe the clinical presentation, diagnostic process, surgical treatment, and outcome of 2 patients with first branchial cleft anomaly. The first case was an 8-year-old girl presented with an elastic lesion located in the left infra-auricular area, in close relation with the lobule, duplicating the external auditory canal. The magnetic resonance imaging revealed a lesion, appearing as a rather well-circumscribed mass within the left parotid gland and duplicating the ear canal. A superficial parotidectomy was subsequently performed, with total excision of the cyst. The second patient was a 15-year-old girl presented with a congenital fistula of the right lateral neck. At superficial parotidectomy, a total excision of the fistula was performed. During the operation the tract was recorded to lay between the branches of the facial nerve, extending with a blind ending canal parallel to the external acoustic meatus. Conclusively, first branchial cleft anomalies are rare malformations with cervical, parotid, or auricular clinical manifestations. Diagnosis of first branchial cleft lesions is achieved mainly through careful physical examination. Complete surgical excision with wide exposure of the lesion is essential in order to achieve permanent cure and avoid recurrence.

  15. Primary mandibular first molar with single root and single canal: a case report of a rare morphology.

    Directory of Open Access Journals (Sweden)

    Zahra Bahrololoomi

    2014-06-01

    Full Text Available Single rooted primary mandibular first molar is a rare developmental anomaly. Literatures reveal that failure of invagination of Hertwig's epithelial root sheath leads to this unusual root form. Thorough knowledge of root canal morphology and anatomical variations of primary teeth can help a pediatric dentist in successful root canal treatment. Hereby, we describe two cases of primary mandibular first molars with an unusual morphology as a single root called pyramidal molar.

  16. Three-dimensional observations of the incisive canal and the surrounding bone using cone-beam computed tomography

    International Nuclear Information System (INIS)

    Asaumi, Rieko; Kawai, Taisuke; Sato, Iwao; Yoshida, Shunji; Yosue, Takashi

    2010-01-01

    The shape of the anterior region of the maxilla is critical when planning implant treatment. The purpose of the present study was to assess the typical morphology of the incisive canal and surrounding bone. In total, 70 maxillae of Japanese dry skulls were used after being divided into dentate and edentulous groups. Cone-beam computed tomography (CBCT) images of the maxilla were acquired by using standardized methods. Using the anterior nasal spine as a reference point, the change in position was measured and analyzed statistically. Also, three-dimensional (3-D) images of the incisive canal were classified into five subsets: cylinder, groove, penetration, bifurcation at the superior portion, and bifurcation at the inferior portion. The quantity of alveolar bone in the incisor region was greatly reduced from the alveolar ridge and labial surface. Moreover, the vertical position of the incisive foramen was significantly (P<0.05) superior in the edentulous groups. Regarding the classification of maxillae by the 3-D shape of the incisive canal, many canals were cylindrical. Horizontal bone reduction from the labial side and vertical bone reduction from the alveolar crest were conspicuous; thus, the angle of the anterior alveolar bone changed after the loss of teeth. The incisive canal diameter in the edentulous group was larger than in the dentate group. The nondestructive assessment of the incisive canals and surrounding bone with CBCT showed two typical shapes for the presence or absence of the incisors. These findings indicate the importance of image diagnosis before esthetic restoration. (author)

  17. Order of 21 May 1979 on Transport of Radioactive Materials by Road or by Inland Waterway (Dangerous Goods 1979, No.5)

    International Nuclear Information System (INIS)

    1979-01-01

    This Order lays down in connection with radioactive materials (class IVb) to be carried by road or inland waterway that Section 32 of the Order of 15 April 1945 approving the transport of dangerous goods by rail, land or inland waterway will come into force on 1 October 1980. The Order prescribes that drivers of land vehicles and on inland waterways, persons responsible on board must carry a certificate concerning their cargo in accordance with the above Section. (NEA) [fr

  18. A study of root canal morphology of human primary incisors and molars using cone beam computerized tomography: an in vitro study.

    Science.gov (United States)

    Gaurav, Vivek; Srivastava, Nikhil; Rana, Vivek; Adlakha, Vivek Kumar

    2013-01-01

    Variations in morphology of root canals in primary teeth usually leads to complications during and after endodontic therapy. To improve the success in endodontics, a thorough knowledge of the root canal morphology is essential. The aim of this study was to assess the variation in number and morphology of the root canals of primary incisors and molars and to study the applicability of cone beam computerized tomography (CBCT) in assessing the same. A total of 60 primary molars and incisors with full root length were collected and various parameters such as the number of roots, number of canals, diameter of root canal at cementoenamel junction and middle-third, length and angulations of roots of primary molars and incisors were studied using CBCT. The observations were put to descriptive statistics to find out the frequency, mean, standard deviation and range for all four subgroups. Further, unpaired t-test was used to compare these parameters between subgroups and analysis of variance test was implemented to evaluate the parameters within the subgroups. The CBCT showed the presence of bifurcation of root canal at middle third in 13% of mandibular incisors while 20% of mandibular molars had two canals in distal root. The diameter of distobuccal root canal of maxillary molars and mesiolingual canal of mandibular molars was found to be minimum. CBCT is a relatively new and effective technology, which provides an auxiliary imaging modality to supplement conventional radiography for assessing the variation in root canal morphology of primary teeth.

  19. Measurement of the percentage of root filling in oval-shaped canals obturated with Thermafil Obturators and Beefill 2in1: In vitro study.

    Science.gov (United States)

    Faus-Llácer, Vicente; Collado-Castellanos, Nicolás; Alegre-Domingo, Teresa; Dolz-Solsona, María; Faus-Matoses, Vicente

    2015-04-01

    The aim of the study was to measure the percentage of root canal fillings in long oval canals obturated with thermoplasticized gutta-percha techniques, Beefill 2in1® and Thermafil Obturators®. Fifty four mandibular incisors were selected after bucco-lingual and mesio-distal radiographs showed at 5 mm from apex an internal long:short diameter ≥2. Teeth were instrumented with Protaper Universal and divided in two groups of 27. Group 1 was obturated with Thermafil Obturators® and group 2 with Beefill 2in1®. Two horizontal sections were cut at 5 and 7 mm from the apex and photographed in a stereo-microscope. The total area of the canal and filled canal in cross-sections were measured with AutoCad and the percentages of gutta-percha-sealer and voids in the canal were obtained. Both systems achieved high percentage of filled canal, Thermafil 96.8% and Beefill 2in1 98.9%. The percentages of voids in both groups were very low. No significant differences were found between the two groups . The percentage obtained at 5 and 7 mm from the apex in both groups showed no significant difference. The percentages of filled canal (gutta-percha-sealer) were high and these two thermoplasticized techniques are suitable for long oval canals obturation. Key words:Long oval canal, oval canal, thermoplasticized obturation.

  20. Ex Vivo Comparison of Mtwo and RaCe Rotary File Systems in Root Canal Deviation: One File Only versus the Conventional Method.

    Science.gov (United States)

    Aminsobhani, Mohsen; Razmi, Hasan; Nozari, Solmaz

    2015-07-01

    Cleaning and shaping of the root canal system is an important step in endodontic therapy. New instruments incorporate new preparation techniques that can improve the efficacy of cleaning and shaping. The aim of this study was to compare the efficacy of Mtwo and RaCe rotary file systems in straightening the canal curvature using only one file or the conventional method. Sixty mesial roots of extracted human mandibular molars were prepared by RaCe and Mtwo nickel-titanium (NiTi) rotary files using the conventional and only one rotary file methods. The working length was 18 mm and the curvatures of the root canals were between 15-45°. By superimposing x-ray images before and after the instrumentation, deviation of the canals was assessed using Adobe Photoshop CS3 software. Preparation time was recorded. Data were analyzed using three-way ANOVA and Tukey's post hoc test. There were no significant differences between RaCe and Mtwo or between the two root canal preparation methods in root canal deviation in buccolingual and mesiodistal radiographs (P>0.05). Changes of root canal curvature in >35° subgroups were significantly more than in other subgroups with smaller canal curvatures. Preparation time was shorter in one file only technique. According to the results, the two rotary systems and the two root canal preparation methods had equal efficacy in straightening the canals; but the preparation time was shorter in one file only group.