Teat apex colonization with coagulase-negative Staphylococcus species before parturition: Distribution and species-specific risk factors.

PubMed

De Visscher, A; Piepers, S; Haesebrouck, F; De Vliegher, S

2016-02-01

Coagulase-negative staphylococci (CNS) are the main cause of bovine intramammary infections and are also abundantly present in extramammary habitats such as teat apices. Teat apex colonization (TAC) with CNS has already been explored in lactating dairy cows at the species level, whereas this is not true for dry cows and end-term heifers. Therefore, the aim of this observational study was to describe CNS TAC in nonlactating dairy cows and end-term heifers in Flemish dairy herds and to identify associated risk factors at the herd, cow, and quarter level. All CNS were molecularly identified to the species level using transfer RNA intergenic spacer PCR (tDNA-PCR) and sequencing of the 16S rRNA gene, allowing for species-specific statistical analyses using multivariable, multilevel logistic regression. Staphylococcus devriesei, Staphylococcus chromogenes, Staphylococcus haemolyticus, and Staphylococcus equorum were the most frequently isolated species. Staphylococcus chromogenes was the sole species colonizing teat apices of cows and heifers in all herds, whereas large between-herd differences were observed for the other species. Teat apices of red and white Holstein Friesians, of quarters dried off without an internal teat sealer, and swabbed in months with lower precipitation and higher ambient temperature were significantly more likely to be colonized by S. devriesei. Slightly dirty teat apices and teat apices swabbed in months with lower precipitation had higher odds of being colonized by S. chromogenes, whereas teat apices sampled in months with lower precipitation and higher ambient temperature were more likely to be colonized by S. haemolyticus. Dirty teat apices and teat apices swabbed in months with lower ambient temperature in combination with low precipitation had higher odds of being colonized by S. equorum. Diverse factors explaining CNS TAC, yet mostly related to humidity, ambient temperature, and hygiene, substantiate differences in epidemiological

The effect of internal teat sealant products (Teatseal and Orbeseal) on intramammary infection, clinical mastitis, and somatic cell counts in lactating dairy cows: a meta-analysis.

PubMed

Rabiee, A R; Lean, I J

2013-01-01

The objective of this study was to assess the efficacy of internal teat sealant products containing bismuth subnitrate (Teatseal and Orbeseal; Pfizer Animal Health, West Ryde, Australia) when used alone, or in the presence of antibiotic dry cow therapy (ADCT), before or at drying off on the incidence of new intramammary infections (IMI), clinical mastitis, and milk somatic cell count (SCC) during lactation. The literature search identified 18 English-language publications on the use of Teatseal in dairy cattle. A total of 12 studies with 17 subtrials or comparisons including 13 positive control subtrials (internal teat sealant and ADCT vs. ADCT) and 4 negative control subtrials (internal teat sealant vs. untreated) examining IMI were included in the analysis. Internal teat sealants, alone or in the presence of ADCT, reduced the risk of acquiring new IMI after calving by 25% [risk ratio (RR)=0.75; 95% confidence interval (CI): 0.67 to 0.83]. Internal teat sealants reduced the risk of IMI by 73% compared with untreated cows (RR=0.27; 95% CI: 0.13 to 0.55). The results of both meta-analyses of IMI, with positive and negative controls, were heterogeneous [I(2) (a statistic that describes the proportion of total variation in study effect estimates that is due to heterogeneity)=65.4 and 92.1%]. No farm or cow factors studied significantly contributed to the heterogeneity of the results. A total of 16 studies (21 subtrials), including 14 positive control subtrials and 7 negative control subtrials, examining clinical mastitis were included in the analysis. Internal teat sealants alone and in the presence of ADCT reduced the risk of clinical mastitis after calving in lactating cows by 29% (RR=0.71; 95% CI: 0.62 to 0.82), and 48% (RR=0.52; 95% CI: 0.37 to 0.75), respectively. The results of the meta-analysis on clinical mastitis with positive controls were homogeneous (I(2)=33.6%), whereas the results of studies with negative controls were heterogeneous (I(2)=60.4%). No farm

Defining standardized protocols for determining the efficacy of a postmilking teat disinfectant following experimental exposure of teats to mastitis pathogens.

PubMed

Schukken, Y H; Rauch, B J; Morelli, J

2013-04-01

The objective of this paper was to define standardized protocols for determining the efficacy of a postmilking teat disinfectant following experimental exposure of teats to both Staphylococcus aureus and Streptococcus agalactiae. The standardized protocols describe the selection of cows and herds and define the critical points in performing experimental exposure, performing bacterial culture, evaluating the culture results, and finally performing statistical analyses and reporting of the results. The protocols define both negative control and positive control trials. For negative control trials, the protocol states that an efficacy of reducing new intramammary infections (IMI) of at least 40% is required for a teat disinfectant to be considered effective. For positive control trials, noninferiority to a control disinfectant with a published efficacy of reducing new IMI of at least 70% is required. Sample sizes for both negative and positive control trials are calculated. Positive control trials are expected to require a large trial size. Statistical analysis methods are defined and, in the proposed methods, the rate of IMI may be analyzed using generalized linear mixed models. The efficacy of the test product can be evaluated while controlling for important covariates and confounders in the trial. Finally, standards for reporting are defined and reporting considerations are discussed. The use of the defined protocol is shown through presentation of the results of a recent trial of a test product against a negative control. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Unraveling the microbiota of teat apices of clinically healthy lactating dairy cows, with special emphasis on coagulase-negative staphylococci.

PubMed

Braem, G; De Vliegher, S; Verbist, B; Piessens, V; Van Coillie, E; De Vuyst, L; Leroy, F

2013-03-01

Swab samples (n=72) obtained from the teat apex of lactating dairy cows without visual signs of inflammation (n=18) were gathered on 2 well-managed Flemish dairy herds (herds 1 and 2) during the same month to assess the bacterial diversity of teat apices before milking. A combination of both culture-dependent [plating and (GTG)(5)-PCR fingerprinting of the colonies] and culture-independent [denaturing gradient gel electrophoresis (PCR-DGGE)] techniques indicated that the teat apices contain a wide diversity of bacterial genera. Despite a low bacterial load, 20 bacterial genera of 3 phyla (Actinobacteria, Firmicutes, and Proteobacteria) were present. The most prevalent bacteria were the coagulase-negative staphylococci (CNS), encompassing a total of 15 species, which were identified to the species level using a combination of (GTG)(5)-PCR fingerprinting, gene sequencing (16S ribosomal RNA and rpoB genes), and a novel PCR-DGGE technique based on the tuf-PCR amplicon. Overall bacterial diversity did not differ significantly between the herds or between noninfected and subclinically infected quarters in herd 1. In herd 1, borderline significant lower CNS species diversity was found on teat apices of noninfected quarters compared with subclinically infected quarters. The most prevalent CNS species were Staphylococcus haemolyticus and Staphylococcus equorum in both herds and Staphylococcus carnosus in herd 2. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Bovine Teat Microbiome Analysis Revealed Reduced Alpha Diversity and Significant Changes in Taxonomic Profiles in Quarters with a History of Mastitis

PubMed Central

Falentin, Hélène; Rault, Lucie; Nicolas, Aurélie; Bouchard, Damien S.; Lassalas, Jacques; Lamberton, Philippe; Aubry, Jean-Marc; Marnet, Pierre-Guy; Le Loir, Yves; Even, Sergine

2016-01-01

Mastitis is a mammary gland inflammatory disease often due to bacterial infections. Like many other infections, it used to be considered as a host-pathogen interaction driven by host and bacterial determinants. Until now, the involvement of the bovine mammary gland microbiota in the host-pathogen interaction has been poorly investigated, and mainly during the infectious episode. In this study, the bovine teat microbiome was investigated in 31 quarters corresponding to 27 animals, which were all free of inflammation at sampling time but which had different histories regarding mastitis: from no episode of mastitis on all the previous lactations (Healthy quarter, Hq) to one or several clinical mastitis events (Mastitic quarter, Mq). Several quarters whose status was unclear (possible history of subclinical mastitis) were classified as NDq. Total bacterial DNA was extracted from foremilk samples and swab samples of the teat canal. Taxonomic profiles were determined by pyrosequencing on 16s amplicons of the V3-4 region. Hq quarters showed a higher diversity compared to Mq ones (Shannon index: ~8 and 6, respectively). Clustering of the quarters based on their bacterial composition made it possible to separate Mq and Hq quarters into two separate clusters (C1 and C2, respectively). Discriminant analysis of taxonomic profiles between these clusters revealed several differences and allowed the identification of taxonomic markers in relation to mastitis history. C2 quarters were associated with a higher proportion of the Clostridia class (including genera such as Ruminococcus, Oscillospira, Roseburia, Dorea, etc.), the Bacteroidetes phylum (Prevotella, Bacteroides, Paludibacter, etc.), and the Bifidobacteriales order (Bifidobacterium), whereas C1 quarters showed a higher proportion of the Bacilli class (Staphylococcus) and Chlamydiia class. These results indicate that microbiota is altered in udders which have already developed mastitis, even far from the infectious episode

Iodide Residues in Milk Vary between Iodine-Based Teat Disinfectants.

PubMed

French, Elizabeth A; Mukai, Motoko; Zurakowski, Michael; Rauch, Bradley; Gioia, Gloria; Hillebrandt, Joseph R; Henderson, Mark; Schukken, Ynte H; Hemling, Thomas C

2016-07-01

Majority of iodine found in dairy milk comes from the diet and teat disinfection products used during milking process. The objective of this study was to evaluate the effects of 4 iodine-based teat dips on milk iodide concentrations varying in iodine level (0.25% vs. 0.5%, w/w), normal low viscosity dip versus barrier dip, and application method (dip vs. spray) to ensure safe iodine levels in dairy milk when these products are used. The iodine exposure study was performed during a 2-wk period. The trial farm was purged of all iodine-based disinfection products for 21 d during a prestudy "washout period," which resulted in baseline milk iodide range of 145 to 182 ppb. During the experiment, iodine-based teat dips were used as post-milking teat disinfectants and compared to a non-iodine control disinfectant. Milk iodide residue levels for each treatment was evaluated from composited group samples. Introduction of different iodine-based teat disinfectants increased iodide residue content in milk relative to the control by between 8 and 29 μg/L when averaged across the full trial period. However, residues levels for any treatment remained well below the consumable limit of 500 μg/L. The 0.5% iodine disinfectant increased milk iodide levels by 20 μg/L more compared to the 0.25% iodine. Compared to dip-cup application, spray application significantly increased milk iodide residue by 21 μg/L and utilized approximately 23% more teat dip. This carefully controlled study demonstrated an increase in milk iodide concentrations from iodine disinfectants, but increases were small and within acceptable limits. © 2016 Institute of Food Technologists®

Pseudomonas aeruginosa mastitis in two goats associated with an essential oil-based teat dip.

PubMed

Kelly, E Jane; Wilson, David J

2016-11-01

Pseudomonas aeruginosa is an opportunistic pathogen that has been associated with mastitis in dairy animals, including goats. Often, the environmental sources of the bacteria are water-related (such as hoses and muddy pastures). Mastitis attributable to P. aeruginosa was identified in 2 goats in a small herd. Efforts were made to identify environmental sources of the pathogen. Multiple samples from the goats' environment were cultured, including water from the trough, bedding, the hose used to wash udders, and the teat dip and teat dip containers. The bacterium was isolated from the teat dip and the teat dip container. The teat dip consisted of water, liquid soap, and several drops of essential oils (including tea tree, lavender, and peppermint). This case illustrates a potential problem that may arise as a result of the use of unconventional ingredients in teat dips. The use of alternative products by goat producers is likely to increase in the future. © 2016 The Author(s).

The Usability of a Pressure-Indicating Film to Measure the Teat Load Caused by a Collapsing Liner

PubMed Central

Demba, Susanne; Elsholz, Sabrina; Ammon, Christian; Rose-Meierhöfer, Sandra

2016-01-01

Prevention of damage to the teat and mastitis requires determination of the teat load caused by a collapsing liner. The aim of this study was to test a pressure-indicating film designed to measure the pressure between a collapsing liner and artificial teats. The Ultra Super Low and the Extreme Low pressure-indicating films were tested on two types of artificial teat. The experiments were performed with a conventional milking cluster equipped with round silicone liners. For each teat and film type, 30 repetitions were performed. Each repetition was performed with a new piece of film. Kruskal-Wallis tests were performed to detect differences between the pressure values for the different teats. The area of regions where pressure-indication color developed was calculated to determine the most suitable film type. Both film types measured the pressure applied to both artificial teats by the teat cup liner. Thus, the pressure-indicating films can be used to measure the pressure between a collapsing liner and an artificial teat. Based on the results of the present investigation, a pressure-indicating film with the measurement ranges of both film types combined would be an optimal tool to measure the overall pressure between an artificial teat and a collapsing liner. PMID:27690033

Short communication: Pre- and postmilking anatomical characteristics of teats and their associations with risk of clinical mastitis in dairy cows.

PubMed

Guarín, J F; Ruegg, P L

2016-10-01

The primary objective of this study was to describe and compare anatomical characteristics of teats before and after machine milking adjusted for parity and teat location (front versus rear). The second objective was to determine if selected milking and anatomical characteristics of teats were associated with occurrence of clinical mastitis. To address objective 1, a cross-sectional study was done to describe and compare teat dimensions before and after milking (n=1,751 teats from 445 cows). To fulfill objective 2, a case-control study was performed. Quarters having their first case of clinical mastitis in the current lactation from 2 mo before to 2 mo after the day the teats were measured were selected as cases (n=47), provided no other quarters from that cow were affected by clinical mastitis at that time. Three controls (n=141) were matched with each case; these were selected from quarters that did not experience any case of clinical mastitis during their current lactation. A conditional logistic regression model was used to determine associations between teat dimensions and occurrence of clinical mastitis. Primiparous and multiparous Holstein cows were enrolled in both studies. As compared with premilking dimensions, postmilking teats were longer and narrower at the barrel and the apex. Significant interactions between teat position and parity were identified for premilking teat length and diameter of the teat barrel. Premilking, teats were longer and wider with increasing parity. Front teats were longer and wider than rear teats premilking. Also during premilking, differences between the front and rear teat were less at increasing parity. Teat apex diameter was greater for premilking teats of cows in parity ≥3 and the apexes of front teats were wider than those of rear teats. Teats enrolled in the case-control study had twice as many clinical mastitis cases in front quarters compared with rear quarters. Premilking diameter of the teat apex was positively

Presence of archaea and selected bacteria in infected root canal systems.

PubMed

Brzezińska-Błaszczyk, Ewa; Pawłowska, Elżbieta; Płoszaj, Tomasz; Witas, Henryk; Godzik, Urszula; Agier, Justyna

2018-05-01

Infections of the root canal have polymicrobial etiology. The main group of microflora in the infected pulp is bacteria. There is limited data that archaea may be present in infected pulp tissue. The aim of this study was to check the prevalence of archaea in necrotic root canal samples obtained from patients with primary or post-treatment infection. The prevalence of selected bacteria species (Prevotella intermedia, Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Synergistes sp.) in necrotic samples was evaluated as well. Sixty-four samples from root canal were collected for DNA and RNA extraction. A PCR assay based on the 16S rRNA gene was used to determine the presence of archaea and selected bacteria. Of the 64 samples, 6 were analyzed by semiquantitative reverse transcription PCR to estimate expression profiles of 16S rRNA, and another 9 were selected for direct sequencing. Archaea were detected in 48.4% samples. Statistical analysis indicated a negative association in coexistence between archaea and Treponema denticola (P < 0.05; Pearson's χ 2 test). The main representative of the Archaea domain found in infected pulp tissue was Methanobrevibacter oralis. Archaea 16S rRNA gene expression was significantly lower than Synergistes sp., Porphyromonas gingivalis, and Tannerella forsythia (P < 0.05; Student's t test). Thus, it can be hypothesized that archaea may participate in the endodontic microbial community.

Live Helicobacter pylori in the root canal of endodontic-infected deciduous teeth.

PubMed

Hirsch, Christian; Tegtmeyer, Nicole; Rohde, Manfred; Rowland, Marion; Oyarzabal, Omar A; Backert, Steffen

2012-08-01

Many polymerase chain reaction (PCR)-based studies have shown that Helicobacter pylori DNA is prevalent in the oral cavity, but reports on the isolation of live bacteria are extremely rare. Thus, it is still unclear whether H. pylori can indeed survive in the oral environment. Here we used electron microscopy, selective growth techniques, urease assays, 16S rRNA PCR, and western blotting to investigate the possible presence of live H. pylori in 10 root canal and corresponding plaque samples of endodontic-infected deciduous teeth in three children. Although H. pylori DNA was verifiable by PCR in several plaque and root canal samples, bacterial colonies could only be grown from two root canals, but not from plaque. These colonies were unequivocally identified as H. pylori by microscopic, genetic, and biochemical approaches. Our findings show that root canals of endodontic-infected teeth may be a reservoir for live H. pylori that could serve as a potential source for transmission.

In vivo studies on lysosubtilin. 3. Efficacy for treatment of mastitis and superficial lesions of the udder and teats in cows.

PubMed

Biziulevichius, G A; Lukauskas, K

1998-01-01

Lysosubtilin is a broad-spectrum preparation of lytic enzymes from Bacillus subtilis designed for veterinary medicine. This study demonstrates its efficacy for the treatment of reproductive system diseases (mastitis, superficial lesions of the udder and teats) in cows. Prior to determination of optimal therapeutic doses, samples taken from the milk and udder skin of sick animals were examined microbiologically. The examinations revealed a high incidence of polymicrobial infections (26.9 and 84.9% for mastitis and superficial udder lesions, respectively) caused by various mixtures of bacteria (both Gram-positive and Gram-negative) and fungi/yeasts. Dose determination studies involved 115 cows with clinical signs of mastitis. The optimal dose for mastitis treatment was found to be 3.5 x 10(6) U lysosubtilin dissolved in 100 mL of distilled water, which was then administered into the mammary gland via the teat canal once daily until recovery. Such a dose yielded statistically significant decreases (P < 0.05) both in the length of time before clinical recovery (2 d versus 4 and 4.5 d with either of the two antibiotic-based traditional drugs) and in the percentage of animals who suffered relapses within a 2-month period following treatment (5% versus 60%, with one of the two drugs). A field experiment involving 106 cows was designed to compare the efficacy of 1% lysosubtilin water-glycerin solution (1:9 v/v) and other traditional medications for the topical treatment of superficial lesions of the udder and teats as well as its potential for mastitis prevention. All drugs used yielded a 100% cure rate, but lysosubtilin application made it possible to achieve a statistically significant decrease (P < 0.05) in the duration of the recovery period (2.5 d versus 4.5 to 5.5 d) when compared with any of the four other drugs tested. Its efficacy for mastitis prevention was at least 3.4 times higher than the efficacy of the other medications used (statistically significant, P < 0

A genome-wide association study reveals a QTL influencing caudal supernumerary teats in Holstein cattle.

PubMed

Joerg, H; Meili, C; Ruprecht, O; Bangerter, E; Burren, A; Bigler, A

2014-12-01

Supernumerary teats represent a common abnormality of the bovine udder. A genome-wide association study was performed based on the proportion of the occurrence of supernumerary teats in the daughters of 1097 Holstein bulls. The heritability of caudal supernumerary teats without mammary gland in this study was 0.604. The largest proportion of the heritability was attributable to BTA 20. The strongest evidence for association was with five SNPs on chromosome 20, referred to as a QTL. The mode of inheritance at this QTL was dominant. These findings reveal that the occurrence of caudal supernumerary teats without mammary gland in Holstein cattle is influenced by a QTL on chromosome 20 and a polygenic part. The data support the high potential of the SNPs in the QTL region as markers for breeding against caudal supernumerary teats. © 2014 Stichting International Foundation for Animal Genetics.

Experimental root canal infections in conventional and germ-free mice.

PubMed

Sobrinho, A P; Barros, M H; Nicoli, J R; Carvalho, M A; Farias, L M; Bambirra, E A; Bahia, M G; Vieira, E C

1998-06-01

A small animal model was evaluated to study the interrelationships between microorganisms after their implantation in root canals (inferior central incisors) using germ-free (GF) and conventional (CV) mice. The selected microorganisms were: Porphyromonas endodontalis (ATCC 35406), Eubacterium lentum (ATCC 25559), Peptostreptococcus anaerobius (ATCC 27337), Fusobacterium nucleatum (ATCC 10953), Escherichia coli (ATCC 25922), and Enterococcus faecalis (ATCC 4083). Only P. anaerobius, E. coli, and E. faecalis, respectively, were able to colonize when inoculated alone into the root canal of both CV and GF mice. E. lentum, when inoculated alone colonized only in CV animals. P. endodontalis and F. nucleatum were unable to colonize in CV and GF animals after single inoculation. It is concluded that the experimental animal model presented herein is valuable for ecological studies of root canal infections and that only some strict anaerobic bacteria are able to colonize mice root canals when inoculated by themselves alone in pure culture.

Large Reactional Osteogenesis in Maxillary Sinus Associated with Secondary Root Canal Infection Detected Using Cone-beam Computed Tomography.

PubMed

Estrela, Carlos; Porto, Olavo César Lyra; Costa, Nádia Lago; Garrote, Marcel da Silva; Decurcio, Daniel Almeida; Bueno, Mike R; Silva, Brunno Santos de Freitas

2015-12-01

Inflammatory injuries in the maxillary sinus may originate from root canal infections and lead to bone resorption or regeneration. This report describes the radiographic findings of 4 asymptomatic clinical cases of large reactional osteogenesis in the maxillary sinus (MS) associated with secondary root canal infection detected using cone-beam computed tomographic (CBCT) imaging. Apical periodontitis, a consequence of root canal infection, may lead to a periosteal reaction in the MS and osteogenesis seen as a radiopaque structure on imaging scans. The use of a map-reading strategy for the longitudinal and sequential slices of CBCT images may contribute to the definition of diagnoses and treatment plans. Root canal infections may lead to reactional osteogenesis in the MS. High-resolution CBCT images may reveal changes that go unnoticed when using conventional imaging. Findings may help define initial diagnoses and therapeutic plans, but only histopathology provides a definitive diagnosis. Surgical enucleation of the periapical lesion is recommended if nonsurgical root canal treatment fails to control apical periodontitis. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

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

PubMed

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; P<0.05). There was no significant association between B. forsythus and sinus tract of apical periodontitis (OR=1.33). B. forsythus colonized in the infected root canals. It is the putative pathogen of apical periodontitis.

The pore of the leaf cavity of Azolla species: teat cell differentiation and cell wall projections.

PubMed

Veys, P; Lejeune, A; Van Hove, C

2002-02-01

The differentiation of the specialized secretory teat cells of the leaf cavity pore of Azolla species was investigated at the ultrastructural level with emphasis on their peculiar cell wall projections. The results indicated that the projections are formed as soon as the teat cells complete their differentiation and that their production is principally associated with changes in endoplasmic reticulum profiles. The number of projections increases with the teat cell age and is stimulated under salt and P deficiency stresses. Salt stress also promotes their emergence on Azolla species that under normal conditions do not produce projections. Cytochemical tests on different Azolla species showed that the projection composition is almost identical: proteins, acidic polysaccharides, and pectin are always detected. This study revealed that Azolla teat cell projections differ fundamentally from other types of hitherto described cell wall projections that are considered as remnant structures from cell separation. In contrast, in Azolla teat cells projections are actively produced and compounds are excreted by an exocytotic mechanism. The possible role of the projections in the symbiosis of Azolla spp. with Anabaena azollae is discussed.

Development of a Control System for the Teat-End Vacuum in Individual Quarter Milking Systems

PubMed Central

Ströbel, Ulrich; Rose-Meierhöfer, Sandra; Öz, Hülya; Brunsch, Reiner

2013-01-01

Progress in sensor technique and electronics has led to a decrease in the costs of electronic and sensor components. In modern dairy farms, having udders in good condition, a lower frequency of udder disease and an extended service life of dairy cows will help ensure competitiveness. The objective of this study was to develop a teat-end vacuum control system with individual quarter actor reaction. Based on a review of the literature, this system is assumed to protect the teat tissue. It reduces the mean teat-end vacuum in the maximum vacuum phase (b) to a level of 20 kPa at a flow rate of 0.25 L/min per quarter. At flow rates higher than 1.50 L/min per quarter, the teat-end vacuum can be controlled to a level of 30 kPa, because in this case it is desirable to have a higher vacuum for the transportation of the milk to the receiver. With this system it is possible for the first time to supply the teat end with low vacuum at low flow rates and with higher vacuum at increasing flow rates in a continuous process with a three second reaction-rate on individual quarter level. This system is completely automated. PMID:23765272

Enterococcus faecalis and Candida albicans in the dental root canal and periapical infections.

PubMed

Kovac, J; Kovac, D; Slobodnikova, L; Kotulova, D

2013-01-01

The aim of the present study was to examine the prevalence of Enterococcus faecalis and Candida albicans in endodontic infections. Samples for microbiological examination were collected from 32 patients with deep dental caries, infected dental root canal, or periapical infection. Cultivation of the dental samples yielded four strains of Enterococcus faecalis (12.5 %), and three strains of Candida albicans (9.4 %). All Enterococcus faecalis isolates were susceptible to ampicillin, one isolate was resistant to tetracycline, two to erythromycin and azithromycin (additional 2 had intermediate susceptibility), and one strain had intermediate susceptibility to ciprofloxacin and moxifloxacin. We conclude that Enterococcus faecalis and Candida albicans can participate in the dental root canal and periapical infections, and the use of effective irrigant solutions and intracanal medicaments active against these microbes is important in order to prevent endodontic therapy failures. Unexpected was the isolation of C. albicans from a nine-year-old child with periodontitis apicalis. This finding must draw attention to the possibility that even at such a young age, this microorganism could be a potential etiological agent in endodontic infections (Tab. 2, Ref. 34). Text in PDF www.elis.sk.

Effect of pre-milking teat disinfection on clinical mastitis incidence in a dairy herd in Northern Queensland, Australia.

PubMed

Rowe, S M; Tranter, W P; Laven, R A

2018-03-01

To determine if a pre-milking teat disinfection protocol would reduce the incidence of clinical mastitis by greater than 50%. Two pre-milking routines were compared in a natural exposure trial. Cows from a single dairy herd were randomly assigned to control (n = 246) and experimental (pre-milking teat disinfection [PMTD]; n = 244) groups. For cows in the control group, the pre-milking routine involved minimal teat-washing, except for cows with wet teat contamination. For cows in the PMTD group, the pre-milking routine involved washing of all teats, dipping with a commercial 0.1% available iodine solution, allowing a minimum of 30 s contact time and then drying of the teats using disposable paper towel. Clinical cases encountered during the trial were recorded and pathogens were isolated from milk samples using standard laboratory methods. The effect of PMTD was determined using multivariable binary logistic regression. Multiparous animals in the PMTD group had higher odds of experiencing clinical mastitis overall and of experiencing clinical mastitis caused by environmental pathogens (odds ratio (OR) 1.97 and 4.11, 95% confidence interval (CI) 1.15-3.38 and 1.49-11.3, respectively). In primiparous animals, pre-milking teat disinfection did not reduce the odds of clinical mastitis by greater than 50% (OR 1.31, 95%CI 0.52-3.29). In this herd, PMTD increased the odds of clinical mastitis. The effectiveness of PMTD to prevent clinical mastitis in pasture-based systems is likely to vary greatly between herds. We therefore recommend against the wholesale use of this practice on Australian farms. © 2018 Australian Veterinary Association.

Characterisation of Roseomonas mucosa isolated from the root canal of an infected tooth.

PubMed

Diesendorf, Nina; Köhler, Stefanie; Geißdörfer, Walter; Grobecker-Karl, Tanja; Karl, Matthias; Burkovski, Andreas

2017-06-14

The genus Roseomonas comprises a group of pink-pigmented, slow-growing, aerobic, non-fermentative Gram-negative bacteria, which have been isolated from environmental sources such as water and soil, but are also associated with human infections. In the study presented here, Roseomonas mucosa was identified for the first time as part of the endodontic microbiota of an infected root canal and characterised in respect to growth, antibiotic susceptibility and biofilm formation. The isolated R. mucosa strain showed strong slime formation and was resistant to most β-lactam antibiotics, while it was susceptible to aminoglycosides, carbapenemes, fluorochinolones, polymyxines, sulfonamides and tetracyclines. Biofilm formation on artificial surfaces (glass, polystyrene, gutta-percha) and on teeth was tested using colorimetric and fluorescence microscopic assays. While solid biofilms were formed on glass surfaces, on the hydrophobic surface of gutta-percha points, no confluent but localised, spotty biofilms were observed. Furthermore, R. mucosa was able form biofilms on dentin. The data obtained indicate that R. mucosa can support establishment of endodontic biofilms and furthermore, infected root canals might serve as an entrance pathway for blood stream infections by this emerging pathogen.

Cross-sectional study to identify staphylococcal species isolated from teat and inguinal skin of different-aged dairy heifers.

PubMed

Adkins, P R F; Dufour, S; Spain, J N; Calcutt, M J; Reilly, T J; Stewart, G C; Middleton, J R

2018-04-01

The purpose of this study was to describe the prevalence and distribution of staphylococcal species on the teat and inguinal skin of dairy heifers across the various stages of the heifer life cycle. The cross-sectional study included 106 Holstein heifers with an age range of 0 d to 27 mo that were selected from 11 different groups, based on housing type and age, on a single dairy operation. A composite swabbing sample including all 4 teats and a second composite sample including both inguinal regions of each heifer were collected using gas-sterilized electrostatic dusters (Swiffers; Procter and Gamble, Cincinnati, OH). Swabbing samples were mixed with 10 mL of sterile saline, agitated, and cultured on mannitol salt agar plates. At 24 h, plates were read and up to 10 staphylococcal colonies were saved for further analysis. Staphylococcal isolates were speciated using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry or PCR amplification and partial sequencing of rpoB or tuf. The prevalence of staphylococci was compared between the inguinal and teat regions using the chi-squared or Fisher's exact test, as applicable. Logistic regression models were used to investigate the relationship between a heifer's age (treated as a quantitative continuous variable) and the probability of isolating a given staphylococcal species from a given body site (inguinal region or teats). Overall, the most common species identified were Staphylococcus haemolyticus followed by Staphylococcus chromogenes, Staphylococcus xylosus, Staphylococcus devriesei, and Staphylococcus sciuri. Staphylococcus aureus was more prevalent on the teat than in the inguinal region, whereas Staphylococcus arlettae was more prevalent in the inguinal region than on the teat. All other staphylococcal species were as likely to be found on the teat skin as the inguinal region skin. Isolation from the inguinal and teat skin was associated with age for Staphylococcus agnetis, S. chromogenes

Pattern of Blood Stream Infections within Neonatal Intensive Care Unit, Suez Canal University Hospital, Ismailia, Egypt.

PubMed

Kishk, Rania Mohammed; Mandour, Mohamed Fouad; Farghaly, Rasha Mohamed; Ibrahim, Ahmed; Nemr, Nader Attia

2014-01-01

Introduction. Blood stream infection (BSI) is a common problem of newborn in neonatal intensive care units (NICUs). Monitoring neonatal infections is increasingly regarded as an important contributor to safe and high-quality healthcare. It results in high mortality rate and serious complications. So, our aim was to determine the incidence and the pattern of BSIs in the NICU of Suez Canal University Hospital, Egypt, and to determine its impact on hospitalization, mortality, and morbidity. Methods. This study was a prospective one in which all neonates admitted to the NICUs in Suez Canal University hospital between January, 2013 and June 2013 were enrolled. Blood stream infections were monitored prospectively. The health care associated infection rate, mortality rate, causative organism, and risk factors were studied. Results. A total of 317 neonates were admitted to the NICU with a mortality rate of 36.0%. During this study period, 115/317 (36.3%) developed clinical signs of sepsis and were confirmed as BSIs by blood culture in only 90 neonates with 97 isolates. The total mean length of stay was significantly longer among infected than noninfected neonates (34.5 ± 18.3 and 10.8 ± 9.9 days, resp., P value < 0.001). The overall mortality rates among infected and noninfected neonates were 38.9% and 34.8%, respectively, with a significant difference. Klebsiella spp. were the most common pathogen (27.8%) followed by Pseudomonas (21.6%) and Staphylococcus aureus (15.4%). Conclusion. The rate of BSIs in NICU at Suez Canal University Hospital was relatively high with high mortality rate (36.0%).

Pattern of Blood Stream Infections within Neonatal Intensive Care Unit, Suez Canal University Hospital, Ismailia, Egypt

PubMed Central

Kishk, Rania Mohammed; Mandour, Mohamed Fouad; Farghaly, Rasha Mohamed; Ibrahim, Ahmed; Nemr, Nader Attia

2014-01-01

Introduction. Blood stream infection (BSI) is a common problem of newborn in neonatal intensive care units (NICUs). Monitoring neonatal infections is increasingly regarded as an important contributor to safe and high-quality healthcare. It results in high mortality rate and serious complications. So, our aim was to determine the incidence and the pattern of BSIs in the NICU of Suez Canal University Hospital, Egypt, and to determine its impact on hospitalization, mortality, and morbidity. Methods. This study was a prospective one in which all neonates admitted to the NICUs in Suez Canal University hospital between January, 2013 and June 2013 were enrolled. Blood stream infections were monitored prospectively. The health care associated infection rate, mortality rate, causative organism, and risk factors were studied. Results. A total of 317 neonates were admitted to the NICU with a mortality rate of 36.0%. During this study period, 115/317 (36.3%) developed clinical signs of sepsis and were confirmed as BSIs by blood culture in only 90 neonates with 97 isolates. The total mean length of stay was significantly longer among infected than noninfected neonates (34.5 ± 18.3 and 10.8 ± 9.9 days, resp., P value < 0.001). The overall mortality rates among infected and noninfected neonates were 38.9% and 34.8%, respectively, with a significant difference. Klebsiella spp. were the most common pathogen (27.8%) followed by Pseudomonas (21.6%) and Staphylococcus aureus (15.4%). Conclusion. The rate of BSIs in NICU at Suez Canal University Hospital was relatively high with high mortality rate (36.0%). PMID:25389439

Molecular characterization of the microbial flora residing at the apical portion of infected root canals of human teeth.

PubMed

Chugal, Nadia; Wang, Jen-Kuei; Wang, Renke; He, Xuesong; Kang, Mo; Li, Jiyao; Zhou, Xuedong; Shi, Wenyuan; Lux, Renate

2011-10-01

This study investigated the bacterial communities residing in the apical portion of human teeth with apical periodontitis in primary and secondary infections by using a culture-independent molecular biology approach. Root canal samples from the apical root segments of extracted teeth were collected from 18 teeth with necrotic pulp and 8 teeth with previous endodontic treatment. Samples were processed for amplification via polymerase chain reaction and separated with denaturing gradient gel electrophoresis. Selected bands were excised from the gel and sequenced for identification. Comparable to previous studies of entire root canals, the apical bacterial communities in primary infections were significantly more diverse than in secondary infections (P = .0003). Interpatient and intrapatient comparisons exhibited similar variations in profiles. Different roots of the same teeth with secondary infections displayed low similarity in bacterial composition, whereas an equivalent sample collected from primary infection contained almost identical populations. Sequencing revealed a high prevalence of Fusobacteria, Actinomyces species, and oral Anaeroglobus geminatus in both types of infection. Many secondary infections contained Burkholderiales or Pseudomonas species, both of which represent opportunistic environmental pathogens. Certain microorganisms exhibit similar prevalence in primary and secondary infection, indicating that they are likely not eradicated during endodontic treatment. The presence of Burkholderiales and Pseudomonas species underscores the problem of environmental contamination. Treatment appears to affect the various root canals of multirooted teeth differently, resulting in local changes of the microbiota. Copyright © 2011 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

High Prevalence of Anal Canal High-Risk Human Papillomavirus Infection in Patients With Crohn's Disease.

PubMed

Vuitton, Lucine; Jacquin, Elise; Parmentier, Anne-Laure; Crochet, Elise; Fein, Francine; Dupont-Gossart, Anne-Claire; Plastaras, Laurianne; Bretagne, Charles-Henri; Mauny, Frédéric; Koch, Stéphane; Prétet, Jean-Luc; Mougin, Christiane; Valmary-Degano, Séverine

2018-03-15

The increasing incidence of anal canal carcinomas requires better knowledge on anal human papillomavirus (HPV) infection. We aimed to assess anal canal HPV infection prevalence and risk factors among patients seen at a gastroenterology department in France. We analyzed anal tissue samples collected from 469 consecutive patients (median age 54 years, 52% women), including 112 who received immunosuppressant therapies and 101 with inflammatory bowel disease (70 with Crohn's disease), who underwent colonoscopy examinations from April 1, 2012 to April 30, 2015. HPV was detected and genotyped using the INNO-LiPA assay, and we collected medical and demographic data from all subjects. Risk factors for any HPV, high-risk HPV (HR-HPV) and HPV16 infection were assessed by bivariate and multivariate analysis. The primary outcomes association of HR-HPV or HPV16 with medical and demographic features. We detected HPV DNA in anal tissues from 34% of the subjects and HR-HPV in 18%. HPV16 was the most prevalent genotype (detected in 7%), followed by HPV51, HPV52, and HPV39. HR-HPV was detected in a significantly higher proportion of samples from women (23.1%) than men (12.8%) (P = .0035); HR-HPV and HPV16 were detected in a significantly higher proportion of patients with Crohn's disease (30.0%) than without (18.1%) (P = .005). Female sex, history of sexually transmitted disease, lifetime and past year-number of sexual partners, active smoking, and immunosuppressive therapies were independent risk factors for anal HR-HPV infection in multivariate analysis. One third of patients who underwent colonoscopy at a gastroenterology department were found to have anal canal HPV infection. We detected HR-HPV infection in almost 20% of patients and in a significantly higher proportion of patients with Crohn's disease than without. Increasing our knowledge of HPV infection of anal tissues could help physicians identify populations at risk and promote prophylaxis with vaccination and adequate

Genetic relationships among milk production and teat and udder scores in cows sired by seven prominent beef cattle breeds

USDA-ARS?s Scientific Manuscript database

Milk production and teat and udder quality are key components to lifetime cow productivity in commercial beef cattle. Our objective was to determine genetic relationships and breed differences for milk production and teat and udder quality in young and mature cows. Cows (n = 602) were crosses of F...

[Frequency of Candida in root canals of teeth with primary and persistent endodontic infections].

PubMed

Bernal-Treviño, Angel; González-Amaro, Ana María; Méndez González, Verónica; Pozos-Guillen, Amaury

Microbiological identification in endodontic infections has focused mainly on bacteria without giving much attention to yeasts, which, due to their virulence factors, can affect the outcomes of root canal treatment. To determine the frequency of Candida in anaerobic conditions in root canals with primary and persistent endodontic infection, as well as to evaluate a microbiological sampling method using aspiration compared to the traditional absorption method with paper points. Fifty microbiological samples were obtained from teeth of 47 patients requiring endodontic treatments, due to either primary or persistent infections. Two microbiological sampling methods were used: an aspiration method, and the traditional paper point absorption method. In each of these methods, two types of medium were used (M 1 -M 4 ). Samples were cultured under anaerobic conditions until reaching 0.5 McFarland turbidity, and then inoculated on Sabouraud dextrose, as well as on anaerobic enriched blood agar plates. Macroscopic and microscopic observations of the colonies were performed. The germ-tube test, growth on CHROMagar, and biochemical identification were performed on the isolated yeasts. Fungal infection was found in 18 (36%) samples out of the 50 teeth evaluated. In the 18 samples positive for fungal infection, 15 out of 36 (41.6%) teeth were taken from a primary infection, and 3 out of 14 (21.4%) from a persistent infection. The aspiration method using Sabouraud dextrose medium recovered a greater diversity of species. Yeasts frequency was higher in teeth with primary infections compared to teeth with persistent infections. The predominant yeast species was Candida albicans. The aspirating sampling method was more efficient in the recovery of Candida isolates than the traditional absorption method. Copyright © 2018 Asociación Española de Micología. Publicado por Elsevier España, S.L.U. All rights reserved.

Bacterial killing by several root filling materials and methods in an ex vivo infected root canal model.

PubMed

Özcan, E; Eldeniz, A U; Arı, H

2011-12-01

To evaluate the ability of two root canal sealers (Epoxy resin-based AH Plus or polydimethylsiloxane-based GuttaFlow) and five root filling techniques (continuous wave of condensation, Thermafil, lateral condensation, matched taper single gutta-percha point, laterally condensed-matched taper gutta-percha point) to kill bacteria in experimentally infected dentinal tubules. An infected dentine block model was used. One hundred and twenty extracted, single-rooted human teeth were randomly divided into 10 test (n = 10) and 2 control (n = 10) groups. The roots, except negative controls, were infected with Enterococcus faecalis for 21 days. The root canals were then filled using the test materials and methods. Positive controls were not filled. Sterile roots were used as negative controls. Dentine powder was obtained from all root canals using gates glidden drills using a standard method. The dentine powder was diluted and inoculated into bacterial growth media. Total colony-forming units (CFU) were calculated for each sample. Statistical analysis was performed using the Kruskal-Wallis and Mann-Whitney U test. The epoxy resin-based sealer was effective in killing E. faecalis except when using Thermafil (P < 0.05), but the polydimethylsiloxane-based sealer was not effective in killing this microorganism except in the continuous wave group (P < 0.05). In the test model, AH Plus killed bacteria in infected dentine more effectively than GuttaFlow. The filling method was less important than the sealer material. © 2011 International Endodontic Journal.

[Effect of compound Chinese traditional medicine on infected root canal bacteria biofilm].

PubMed

Ma, Rui; Huang, Li-li; Xia, Wen-wei; Zhu, Cai-lian; Ye, Dong-xia

2010-08-01

To assess the efficacy of compound Chinese traditional medicine(CTM), which composed of gallic acid, magnolol and polysaccharide of Blettila striata, against the infected root canal bacterial biofilm. Actinomyces viscosus (Av), Enterococcus faecalis (Ef), Fusobacterium nucleatum (Fn) were composed to form biofilm, then confocal laser scan microscope (CLSM) was used to observe and study the bacterial activity. SAS6.12 software package was used for statistical analysis. The biofilm thickness reduced after treatment by both CTM and ZnO (P>0.05),while there was a significant decrease of the percentage of vital bacterias after treatment by CTM (P<0.01). The compound Chinese traditional medicine is effective on biofilm control, so that it would be an effective disinfecting drug for root canal sealers. Supported by Research Fund of Bureau of Traditional Chinese Medicine of Shanghai Municipality (Grant No.2008L008A).

Effect of application of an external teat sealant and/or oral treatment with a monensin capsule pre-calving on the prevalence and incidence of subclinical and clinical mastitis in dairy heifers.

PubMed

McDougall, S; Parker, K I; Weir, A M; Compton, C W R

2008-06-01

To assess the effect of applying an external teat sealant or a slow-release intraruminal monensin capsule pre-calving on the prevalence and incidence of subclinical or clinical mastitis in dairy heifers post-calving. The studies were undertaken in 13 herds. In two herds application of an external teat sealant was compared with a negative control; in nine herds treatment with monensin was compared with controls, and in two herds treatments were applied in a 2 x 2 factorial design. Heifers were randomly assigned within herd to be treated with a slow-release intraruminal device containing 32 g monensin (n=383), or left as untreated controls (n=389), approximately 30 days before the start of the spring calving period; or to be treated with a latex external teat sealant (n=206) when calving was impending, or be left as untreated controls (n=205). Milk samples were collected from each gland between 0 and 5 days after calving and from any gland diagnosed with clinical mastitis. The effect of the treatments on the prevalence of intramammary infection (IMI), i.e. subclinical mastitis, and clinical mastitis were initially analysed at the univariate level, with associated variables (p<0.2) being used in construction of multivariable models. The prevalence of IMI was 18.4% at the gland level, and coagulase-negative staphylococci followed by Streptococcus uberis were the most common isolates. Treatment with an external teat sealant reduced the prevalence, compared with controls, of any IMI (12.1 (SE 1.7)% vs 16.5 (SE 2.1)%, respectively; p=0.05) or IMI caused by a major pathogen (3.8 (SE 0.8)% vs 6.0 (SE 1.1)%, respectively; p=0.05). Monensin treatment did not affect the prevalence of any IMI (p=0.68) or IMI due to a major pathogen (p=0.11). The cumulative incidence of clinical mastitis was 14.2%. Neither monensin treatment (p=0.47) nor application of an external teat sealant (p=0.71) altered the risk of clinical mastitis. There was no interaction between the monensin and

The susceptibility of bovine udder quarters colonized with Corynebacterium bovis to experimental infection with Staphylococcus aureus or Streptococcus agalactiae.

PubMed Central

Brooks, B W; Barnum, D A

1984-01-01

Twenty bovine udder quarters colonized with Corynebacterium bovis SR6 and 20 uncolonized quarters were challenged by inoculation of Staphylococcus aureus Newbould 305 (ATCC 29740) into the teat cistern. The percentage of infection in quarters colonized with C. bovis (50%) was significantly lower than that in controls (100%). By similar challenge no significant difference was observed between the percentage of infection with Streptococcus agalactiae ATCC 27956 in 33 quarters colonized with C. bovis (70%) compared to 33 controls (87.9%). A total of 37 quarters colonized with C. bovis and 37 control quarters were challenged with Staph. aureus Newbould 305 (ATCC 29740) and Maxi (ATCC 27543) and Strep. agalactiae (ATCC 27956) by exposure of the teat orifice. The percentage of teat ducts colonized with C. bovis which became infected with either pathogen was not different from that for controls. PMID:6372969

Antimicrobial photodynamic therapy combined with conventional endodontic treatment to eliminate root canal biofilm infection.

PubMed

Garcez, Aguinaldo S; Ribeiro, Martha S; Tegos, George P; Núñez, Silvia C; Jorge, Antonio O C; Hamblin, Michael R

2007-01-01

To compare the effectiveness of antimicrobial photodynamic therapy (PDT), standard endodontic treatment and the combined treatment to eliminate bacterial biofilms present in infected root canals. Ten single-rooted freshly extracted human teeth were inoculated with stable bioluminescent Gram-negative bacteria, Proteus mirabilis and Pseudomonas aeruginosa to form 3-day biofilms in prepared root canals. Bioluminescence imaging was used to serially quantify bacterial burdens. PDT employed a conjugate between polyethylenimine and chlorin(e6) as the photosensitizer (PS) and 660-nm diode laser light delivered into the root canal via a 200-micro fiber, and this was compared and combined with standard endodontic treatment using mechanical debridement and antiseptic irrigation. Endodontic therapy alone reduced bacterial bioluminescence by 90% while PDT alone reduced bioluminescence by 95%. The combination reduced bioluminescence by >98%, and importantly the bacterial regrowth observed 24 hours after treatment was much less for the combination (P<0.0005) than for either single treatment. Bioluminescence imaging is an efficient way to monitor endodontic therapy. Antimicrobial PDT may have a role to play in optimized endodontic therapy. (c) 2006 Wiley-Liss, Inc.

Bacterial counts on teat skin and in new sand, recycled sand, and recycled manure solids used as bedding in freestalls.

PubMed

Rowbotham, R F; Ruegg, P L

2016-08-01

On modern dairy farms, environmental mastitis pathogens are usually the predominant cause of mastitis, and bedding often serves as a point of exposure to these organisms. The objective of this longitudinal study was to determine bacterial populations of 4 different bedding types [deep-bedded new sand (NES), deep-bedded recycled sand (RS), deep-bedded manure solids (DBMS), and shallow-bedded manure solids over foam core mattresses (SBMS)] and of teat skin swabs of primarily primiparous cows housed in a single facility over all 4 seasons. Samples of bedding were collected weekly (n=49wk) from pens that each contained 32 lactating dairy cows. Throughout the length of the same period, composite swabs of teat skin were collected weekly from all cows before and after premilking teat sanitation. Median numbers of streptococci and streptococci-like organisms (SSLO) were >8.6×10(6) cfu/g and >6.9×10(3) cfu/teat swab for all bedding types and teat swabs, respectively. Numbers of SSLO were greatest in samples of SBMS (2.1×10(8) cfu/g) and least in samples of NES (8.6×10(6) cfu/g), RS (1.3×10(7) cfu/g), and DBMS (1.7×10(7) cfu/g). Numbers of gram-negative bacteria in bedding (5.5×10(4) to 1.2×10(7) cfu/g) were fewer than numbers of SSLO (8.6×10(6) to 2.1×10(8) cfu/g). Numbers of coliform bacteria were greatest in samples of DBMS (2.2×10(6) cfu/g) and least in samples of NES (3.6×10(3) cfu/g). In general, the relative number of bacteria on teat skin corresponded to exposure in bedding. Numbers of gram-negative bacteria recovered from prepreparation teat swabs were greatest for cows bedded with DBMS (1.0×10(4) cfu/swab) and RS (2.5×10(3) cfu/swab) and least for cows bedded with NES (5.8×10(2) cfu/swab). Median numbers of coliform and Klebsiella spp. recovered from prepreparation teat swabs were below the limit of detection for all cows except those bedded with DBMS. Numbers of SSLO recovered from prepreparation teat swabs were least for cows bedded with DBMS (6.9�

Complex Apical Intraradicular Infection and Extraradicular Mineralized Biofilms as the Cause of Wet Canals and Treatment Failure: Report of 2 Cases.

PubMed

Ricucci, Domenico; Candeiro, George T M; Bugea, Calogero; Siqueira, José F

2016-03-01

This article describes 2 cases that showed persistent intracanal exudation (wet canal) even after several visits of antimicrobial endodontic treatment. Histologic and histobacteriologic investigation was conducted for determination of the cause. The 2 cases involved teeth with apical periodontitis lesions, which presented persistent exudation refractory to treatment after several visits. In case 1, it was not possible to achieve a dry canal, and surgery had to be performed. In case 2, attempts to dry the canal succeeded and the canal was filled, but follow-up examination showed an enlarged apical periodontitis lesion and extraction was performed. Biopsy specimens consisting of the root apex and apical periodontitis lesion for case 1 and the whole root for case 2 were subjected to histologic and histobacteriologic analyses. Both cases showed complex bacterial infection in the apical root, affecting both the intraradicular space and the outer root surface. Case 1 showed bacterial biofilms in ramifications, on untouched walls, and extending to the external root surface to form a thick and partially mineralized structure with high bacterial density. Different bacterial morphotypes were evidenced. Case 2 had a ledge on the apical canal wall created during instrumentation, which was filled with necrotic debris, filling material, and bacteria. The walls of the apical portion of the canal were covered by a bacterial biofilm, which was continuous with a thick extraradicular biofilm covering the cementum and dentin in resorptive defects. The extraradicular biofilm showed areas of mineralization and was dominated by filamentous bacteria. The 2 cases with wet canals and treatment failure were associated with complex persistent infection in the apical part of the root canal system extending to form thick and partially mineralized biofilm structures (calculus) on the outer apical root surface. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All

Impacts of Seasonal Housing and Teat Preparation on Raw Milk Microbiota: a High-Throughput Sequencing Study.

PubMed

Doyle, Conor J; Gleeson, David; O'Toole, Paul W; Cotter, Paul D

2017-01-15

In pasture-based systems, changes in dairy herd habitat due to seasonality results in the exposure of animals to different environmental niches. These niches contain distinct microbial communities that may be transferred to raw milk, with potentially important food quality and safety implications for milk producers. It is postulated that the extent to which these microorganisms are transferred could be limited by the inclusion of a teat preparation step prior to milking. High-throughput sequencing on a variety of microbial niches on farms was used to study the patterns of microbial movement through the dairy production chain and, in the process, to investigate the impact of seasonal housing and the inclusion/exclusion of a teat preparation regime on the raw milk microbiota from the same herd over two sampling periods, i.e., indoor and outdoor. Beta diversity and network analyses showed that environmental and milk microbiotas separated depending on whether they were sourced from an indoor or outdoor environment. Within these respective habitats, similarities between the milk microbiota and that of teat swab samples and, to a lesser extent, fecal samples were apparent. Indeed, SourceTracker identified the teat surface as the most significant source of contamination, with herd feces being the next most prevalent source of contamination. In milk from cows grazing outdoors, teat prep significantly increased the numbers of total bacteria present. In summary, sequence-based microbiota analysis identified possible sources of raw milk contamination and highlighted the influence of environment and farm management practices on the raw milk microbiota. The composition of the raw milk microbiota is an important consideration from both a spoilage perspective and a food safety perspective and has implications for milk targeted for direct consumption and for downstream processing. Factors that influence contamination have been examined previously, primarily through the use of

Impacts of Seasonal Housing and Teat Preparation on Raw Milk Microbiota: a High-Throughput Sequencing Study

PubMed Central

Doyle, Conor J.; Gleeson, David; O'Toole, Paul W.

2016-01-01

ABSTRACT In pasture-based systems, changes in dairy herd habitat due to seasonality results in the exposure of animals to different environmental niches. These niches contain distinct microbial communities that may be transferred to raw milk, with potentially important food quality and safety implications for milk producers. It is postulated that the extent to which these microorganisms are transferred could be limited by the inclusion of a teat preparation step prior to milking. High-throughput sequencing on a variety of microbial niches on farms was used to study the patterns of microbial movement through the dairy production chain and, in the process, to investigate the impact of seasonal housing and the inclusion/exclusion of a teat preparation regime on the raw milk microbiota from the same herd over two sampling periods, i.e., indoor and outdoor. Beta diversity and network analyses showed that environmental and milk microbiotas separated depending on whether they were sourced from an indoor or outdoor environment. Within these respective habitats, similarities between the milk microbiota and that of teat swab samples and, to a lesser extent, fecal samples were apparent. Indeed, SourceTracker identified the teat surface as the most significant source of contamination, with herd feces being the next most prevalent source of contamination. In milk from cows grazing outdoors, teat prep significantly increased the numbers of total bacteria present. In summary, sequence-based microbiota analysis identified possible sources of raw milk contamination and highlighted the influence of environment and farm management practices on the raw milk microbiota. IMPORTANCE The composition of the raw milk microbiota is an important consideration from both a spoilage perspective and a food safety perspective and has implications for milk targeted for direct consumption and for downstream processing. Factors that influence contamination have been examined previously, primarily

Clinical, parasitological and immunological features of canal cleaners hyper-exposed to Schistosoma mansoni in the Sudan

PubMed Central

SATTI, M Z; SULAIMAN, S M; HOMEIDA, M M A; YOUNIS, S A; GHALIB, H W

1996-01-01

The present work was a longitudinal study on Schistosoma mansoni infection in occupationally hyperexposed canal cleaners in the Sudan and the influence of therapy on the parasitological and humoral immune parameters. Chronically infected canal cleaners (n = 28) were more resistant to reinfection (Fisher's exact test, P < 0.05) than newly recruited canal cleaners (n = 17). Chronically infected canal cleaners had a significantly higher degree of Symmers' fibrosis (χ2 = 19.1, P < 0.0001), significantly larger portal vein diameter (P < 0.05) and enlarged spleen (χ2 = 4.2, P < 0.05) than recently infected, newly recruited canal cleaners. ELISA was used to detect IgG, IgA and IgM in response to whole worm homogenate (WWH) and cercarial homogenate (CH). Chronically infected canal cleaners had significantly higher IgG to WWH antigen than newly recruited canal cleaners and normally exposed individuals (P < 0.05), while both chronically infected and newly recruited canal cleaners had higher IgG levels to CH antigen than normally exposed individuals (P < 0.05). The newly recruited canal cleaners had a significantly higher IgM level to CH antigen than chronically infected canal cleaners (P < 0.05). The IgG level to WWH antigen increased significantly after treatment in newly recruited canal cleaners and normally exposed individuals (P < 0.05). The IgA level to CH antigen increased significantly after treatment in the chronically infected group (P < 0.05). Comparison of the serological parameters between the different study groups with regards to infection and treatment is discussed. PMID:9099926

[Study of association between Parvimonas micra and pulp dominant pathogens in the infected root canals with chronic periradicular periodontitis].

PubMed

Ji, Hai; Li, Hong; He, Yanyan; Hou, Benxiang

2014-08-01

To study the prevalence of Parvimonas micra (Pm) and the associations between Pm and pulp dominant pathogens in order to reflect the colonization of Pm in the infected root canals with chronic periradicular periodontitis. A total of 120 teeth diagnosed as chronic periradicular periodontitis from 104 patients were included into the study. The teeth were allocated into untreated (primary infectious) and root-canal- treated (secondary infectious) groups with 60 in either group. Samples were collected from the root canals using sterile files and paper points, and subsequent extraction of bacterial DNA was undertaken. The Pm 16S rDNA level was evaluated using 16S rDNA PCR. The prevalence of Pm in chronic periradicular periodontitis was determined accordingly. Then, the associations of Pm and Enterococcus faecalis (Ef), Porphyromonas endodontalis (Pe) as well as Porphyromonas gingivalis (Pg) were analysed. Pm was detected in 40% (24/60) of the samples from the primary infectious group, 5% (3/60) from the secondary infectious group. The prevalences of Pm from the two groups were different significantly (χ² = 21.06, P < 0.05). Significant correlations (untreated group OR = 5.98, root-canal-treated group OR = 33.50) between Pm and Pe were identified in both groups, while the correlations between Pm and Pg as well as Ef were not of significance, respectively. A significantly higher relevance ratio of Pm was estimated in the primary infectious group than the secondary infectious one. Pm and Pe were correlated significantly in the infected root canals, suggesting a symbiotic relation between these two bacteria.

Antimicrobial Photodynamic Therapy Combined With Conventional Endodontic Treatment to Eliminate Root Canal Biofilm Infection

PubMed Central

Garcez, Aguinaldo S.; Ribeiro, Martha S.; Tegos, George P.; Núñez, Silvia C.; Jorge, Antonio O.C.; Hamblin, Michael R.

2011-01-01

Background and Objective To compare the effectiveness of antimicrobial photodynamic therapy (PDT), standard endodontic treatment and the combined treatment to eliminate bacterial biofilms present in infected root canals. Study Design/Materials and Methods Ten single-rooted freshly extracted human teeth were inoculated with stable bioluminescent Gram-negative bacteria, Proteus mirabilis and Pseudomonas aeruginosa to form 3-day biofilms in prepared root canals. Bioluminescence imaging was used to serially quantify bacterial burdens. PDT employed a conjugate between polyethylenimine and chlorin(e6) as the photosensitizer (PS) and 660-nm diode laser light delivered into the root canal via a 200-µ fiber, and this was compared and combined with standard endodontic treatment using mechanical debridement and antiseptic irrigation. Results Endodontic therapy alone reduced bacterial bioluminescence by 90% while PDT alone reduced bioluminescence by 95%. The combination reduced bioluminescence by >98%, and importantly the bacterial regrowth observed 24 hours after treatment was much less for the combination (P<0.0005) than for either single treatment. Conclusions Bioluminescence imaging is an efficient way to monitor endodontic therapy. Antimicrobial PDT may have a role to play in optimized endodontic therapy. PMID:17066481

Genetic analysis of teat number in pigs reveals some developmental pathways independent of vertebra number and several loci which only affect a specific side

USDA-ARS?s Scientific Manuscript database

Background: Number of functional teats is an important trait in commercial swine production. As litter size increases, the number of teats must also increase to supply nutrition to all piglets. Therefore, a genome-wide association analysis was conducted to identify genomic regions that affect this ...

Short communication: Quantification of the transmission of microorganisms to milk via dirt attached to the exterior of teats.

PubMed

Vissers, M M M; Driehuis, F; Te Giffel, M C; De Jong, P; Lankveld, J M G

2007-08-01

Pathogens and spoilage microorganisms can be transmitted to milk via dirt (e.g., feces, bedding material, soil, or a combination of these) attached to the exterior of the cows' teats. To determine the relevance of this pathway and to perform quantitative microbial risk analysis of the microbial contamination of farm tank milk (FTM), it is important to know the amount of dirt transmitted to milk via the exterior of teats. In this study at 11 randomly selected Dutch farms the amount of dirt transmitted to milk via the exterior of teats is determined using spores of mesophilic aerobic bacteria as a marker for transmitted dirt. The amount of transmitted dirt to milk varied among farms from approximately 3 to 300 mg/L, with an average of 59 mg/L. The usefulness of the data for microbial risk analyses is briefly illustrated using the contamination of FTM with spores of butyric acid bacteria as a case study. In a similar way the data can be used to identify measures to control the contamination of FTM with other microorganisms or chemical residues.

Effect of dry period length on the effect of an intramammary teat sealant on the risk of mastitis in cattle treated with antibiotics at drying off.

PubMed

Laven, R A; Balcomb, C C; Tulley, W T; Lawrence, K E

2014-07-01

The aim of this study was to evaluate, under farm conditions, the use of a teat sealant in addition to whole herd dry cow antibiotic therapy on the risk of clinical mastitis in dairy cattle at pasture, and to evaluate the impact of dry period length on that risk and the impact of the teat sealant on that risk. Dairy cows in three herds which used routine whole herd antibiotic therapy were randomly assigned to receive either treatment with an internal teat sealant (n=322) or no additional treatment (n=313) at drying-off between March and May 2010. All clinical mastitis cases during the dry period and to the end of the subsequent lactation were recorded by farm staff; factors affecting risk of clinical mastitis were then analysed using a Cox proportional hazards model. Median duration of the dry period was 112 days with >25% of cows having a dry period >130 days. The incidence risk of mastitis during lactation for cows treated with teat sealant was 9.9 (95% CI=6.9-13.7) cases per 100 cows compared with 17.9 (95% CI=13.8-22.6) cases per 100 cows for cows treated with antibiotic alone. The addition of a teat sealant to dry cow antibiotic therapy decreased the risk of clinical mastitis only in the first 33 days after calving (Hazard risk 0.24 (95% CI=0.12-0.48)). Length of dry period did not significantly affect the risk of clinical mastitis, or the effect of adding teat sealant to dry cow antibiotic therapy on the risk of clinical mastitis. In these herds where, based on the mastitis history, whole herd antibiotic therapy had been recommended, the use of a teat sealant significantly reduced the risk of clinical mastitis. This effect was limited to the first 33 days after calving; subsequently there was no significant effect of treatment. There was no effect of dry period length on risk of clinical mastitis, nor any significant interaction with treatment. Combination therapy with teat sealant and antibiotic was effective under New Zealand conditions in herds using whole

Risk factors for intramammary infections and subclinical mastitis in post-partum dairy heifers.

PubMed

Krömker, Volker; Pfannenschmidt, Florian; Helmke, Katherina; Andersson, Robby; Grabowski, Nils T

2012-08-01

The prevalence of intramammary infections (IMI) and subclinical mastitis (SCM) in 436 German Holstein heifers was put in relation with clinical findings of the udder and data regarding individual rearing and housing conditions of the animals. The clinical examination took place on the day of the livestock auction (at approximately 41 d in milk, DIM). On that day, 31% of the heifers had IMI in at least one quarter, and 18% of all quarters were infected. Coagulase-negative staphylococci were the most prevalent bacteria isolated, accounting for 68% of the positive samples. Data were analysed by logistic regression. Criteria such as 'juvenile intersucking', 'teats shorter than 35 mm', 'teats with a diameter <18 mm' and 'udder oedema at the day of the auction' were associated with IMI in heifers during the first 41 DIM. Loose-housing systems during pregnancy (as opposed to tie-stalls), juvenile intersucking, clinical mastitis during the first week after calving, teat diameters <18 mm, and employing organic bedding material in the stables before calving were associated with subclinical mastitis.

Proinflammatory Activity of Primarily Infected Endodontic Content against Macrophages after Different Phases of the Root Canal Therapy.

PubMed

Marinho, Ariane C S; Martinho, Frederico C; Leite, Fábio R M; Nascimento, Gustavo G; Gomes, Brenda P F A

2015-06-01

This study investigated the presence of target bacterial species and the levels of endotoxins in teeth with apical periodontitis. Levels of inflammatory mediators (interleukin [IL]-1β and tumor necrosis factor [TNF]-α) were determined after macrophage stimulation with endodontic content after different phases of endodontic therapy using different irrigants. Thirty primarily infected root canals were randomly assigned into 3 groups according to the irrigant used for root canal preparation (n = 10 per group): GI: 2.5% sodium hypochlorite, GII: 2% chlorhexidine gel, and GIII (control group): saline solution. Root canal samples were taken by using paper points before (s1) and after root canal instrumentation (s2), subsequently to 17% EDTA (s3), after 30 days of intracanal medication (Ca[OH]2 + saline solution) (s4), and before root canal obturation (s5). Polymerase chain reaction (16S recombinant DNA) and limulus amebocyte lysate assay were used for bacterial and endotoxin detection, respectively. Macrophages were stimulated with the root canal contents for IL-1β/TNF-α measurement using enzyme-linked immunosorbent assay. Porphyromonas gingivalis (17/30), Porphyromonas endodontalis (15/30), and Prevotella nigrescens (11/30) were the most prevalent bacterial species. At s1, endotoxins were detected in 100% of the root canals (median = 32.43 EU/mL). In parallel, substantial amounts of IL-1β and TNF-α were produced by endodontic content-stimulated macrophages. At s2, a significant reduction in endotoxin levels was observed in all groups, with GI presenting the greatest reduction (P < .05). After a root canal rinse with EDTA (s3), intracanal medication (s4), and before root canal obturation (s5), endotoxin levels reduced without differences between groups (P < .05). IL-1β and TNF-α release decreased proportionally to the levels of residual endotoxin (P < .05). Regardless of the use of sodium hypochlorite or CHX, the greatest endotoxin reduction occurs after

Design and characterisation of a polyethylene oxide matrix with the potential use as a teat insert for prevention/treatment of bovine mastitis.

PubMed

Bhattarai, Sushila; Alany, Raid G; Bunt, Craig R; Abdelkader, Hamdy; Rathbone, Michael J

2015-01-01

This manuscript reports (for the first time) on antibiotic-free polymeric inserts for the prevention and/or treatment of bovine mastitis. Polyethylene oxide (PEO)-based inserts were prepared using different concentrations of various hydrophilic polymers and water-soluble and water-insoluble drug-release-modifying excipients. A simple and scalable melt-extrusion method was employed to prepare the inserts. The prepared inserts were characterised for their dimension, rheological and mechanical properties. The in vitro release of a model bacteriostatic drug (salicylic acid) from the prepared inserts was studied to demonstrate the effectiveness and reproducibility of the melt-extrusion manufacturing method. Further, the in vitro stability of the inserts was evaluated using gel permeation chromatography (GPC) to monitor any change in molecular weight under real-time and accelerated storage conditions. The investigated inserts were stable at accelerated storage conditions over a period of 6 months. PEO inserts have the potential to serve a dual purpose, act as a physical barrier against pathogens invading the teat canal of cows and possibly control the release of a drug.

Acute and latent infection by bovine herpesvirus type 2 in a guinea pig model.

PubMed

Torres, Fabrício Dias; Cargnelutti, Juliana Felipetto; Masuda, Eduardo Kenji; Weiblen, Rudi; Flores, Eduardo Furtado

2010-02-01

Bovine herpetic mammillits is a self-limiting cutaneous disease of the udder and teats of cows associated with bovine herpesvirus 2 (BoHV-2) whose pathogenesis is poorly understood. This article describes the use of guinea pigs (Cavia porcellus) to study the pathogenesis of BoHV-2 infection. Twelve weanling female guinea pigs inoculated subcutaneously with BoHV-2 in the genitalia and teats developed local hyperemia, edema, vesicles, ulcers and scabs. Infectious virus was recovered between days 3 and 7 post-infection (pi) from the genital area (9/12) and teats (1/12); and all inoculated animals seroconverted (virus-neutralizing titers of 16-128). Histological examination of lesions revealed lymphoplasmacytic perivascular infiltrates and intranuclear inclusion bodies in keratinocytes. PCR examination of tissues collected at day 35 pi detected latent viral DNA predominantly in lumbosacral spinal segments. In another experiment, eight females inoculated with BoHV-2 in the genitalia and treated with dexamethasone (Dx) at day 35 pi developed mild to moderate local signs, yet no virus could be recovered from lesions. PCR examination of spinal segments from these animals confirmed the presence of latent viral DNA. These results demonstrate that guinea pigs are susceptible to BoHV-2 infection and therefore may be used to study selected aspects of BoHV-2 biology.

Genome-wide association study and accuracy of genomic prediction for teat number in Duroc pigs using genotyping-by-sequencing.

PubMed

Tan, Cheng; Wu, Zhenfang; Ren, Jiangli; Huang, Zhuolin; Liu, Dewu; He, Xiaoyan; Prakapenka, Dzianis; Zhang, Ran; Li, Ning; Da, Yang; Hu, Xiaoxiang

2017-03-29

The number of teats in pigs is related to a sow's ability to rear piglets to weaning age. Several studies have identified genes and genomic regions that affect teat number in swine but few common results were reported. The objective of this study was to identify genetic factors that affect teat number in pigs, evaluate the accuracy of genomic prediction, and evaluate the contribution of significant genes and genomic regions to genomic broad-sense heritability and prediction accuracy using 41,108 autosomal single nucleotide polymorphisms (SNPs) from genotyping-by-sequencing on 2936 Duroc boars. Narrow-sense heritability and dominance heritability of teat number estimated by genomic restricted maximum likelihood were 0.365 ± 0.030 and 0.035 ± 0.019, respectively. The accuracy of genomic predictions, calculated as the average correlation between the genomic best linear unbiased prediction and phenotype in a tenfold validation study, was 0.437 ± 0.064 for the model with additive and dominance effects and 0.435 ± 0.064 for the model with additive effects only. Genome-wide association studies (GWAS) using three methods of analysis identified 85 significant SNP effects for teat number on chromosomes 1, 6, 7, 10, 11, 12 and 14. The region between 102.9 and 106.0 Mb on chromosome 7, which was reported in several studies, had the most significant SNP effects in or near the PTGR2, FAM161B, LIN52, VRTN, FCF1, AREL1 and LRRC74A genes. This region accounted for 10.0% of the genomic additive heritability and 8.0% of the accuracy of prediction. The second most significant chromosome region not reported by previous GWAS was the region between 77.7 and 79.7 Mb on chromosome 11, where SNPs in the FGF14 gene had the most significant effect and accounted for 5.1% of the genomic additive heritability and 5.2% of the accuracy of prediction. The 85 significant SNPs accounted for 28.5 to 28.8% of the genomic additive heritability and 35.8 to 36.8% of the accuracy of

The effect of age and teat order on alpha1-acid glycoprotein, neutrophil-to-lymphocyte ratio, cortisol, and average daily gain in commercial growing pigs.

PubMed

Stull, C L; Kachulis, C J; Farley, J L; Koenig, G J

1999-01-01

The objectives of the study were to evaluate age and teat order on a performance trait, average daily gain, and on physiological stress indicators, alpha1-acid glycoprotein (AGP), neutrophil-to-lymphocyte ratio (N:L), and cortisol in commercial growing pigs from weaning to market age. Pigs (n = 129) from five commercial California farms were weighed and blood-sampled at 28-d intervals from 28 to 168 d of age. Laboratory assays were performed from blood samples to quantify cortisol, AGP, and N:L. Age and facility effects (P<.001), but not teat order effects (P>.05), were found for all three physiological traits and ADG. Pigs that routinely suckled from teats 1, 4, or 6 (numbered from anterior to posterior on the upper teat bank) had similar (P>.05) ADG and BW throughout the production cycle. No correlation (P> .05) was found between cortisol, AGP, and N:L. The use of these physiological and production traits as stress and health indices of growing pigs in commercial facilities has limitations in comparing data between facilities or different ages of pigs.

The effect of a cannula milk sampling technique on the microbiological diagnosis of bovine mastitis.

PubMed

Friman, M; Hiitiö, H; Niemi, M; Holopainen, J; Pyörälä, S; Simojoki, H

2017-08-01

Two methods of collecting milk samples from mastitic bovine mammary quarters were compared. Samples were taken in a consistent order in which standard aseptic technique sampling was done first, followed by insertion of a sterile cannula through the teat canal and collection of a second sample. Microbiological results of those two sampling techniques were compared. Milk samples were analysed using multiplex real-time polymerase chain reaction (PCR). The cannula technique produced a reduced number of microbial species or groups of species per sample compared with conventional sampling. Staphylococcus spp. were the most common species identified and were detected more often during conventional sampling than with cannula sampling. Staphylococcus spp. identified in milk samples could also have originated from the teat canal without being present in the milk. The number of samples positive for Trueperella pyogenes or yeasts in the conventional samples was twice as high as in the cannula samples, indicating that the presence of Trueperella pyogenes and yeast species should not necessarily be interpreted as being the causative agents of bovine intra-mammary infections (IMI). Copyright © 2017 Elsevier Ltd. All rights reserved.

Location-specific expression of chemokines, TNF-α and S100 proteins in a teat explant model.

PubMed

Lind, Monique; Sipka, Anja S; Schuberth, Hans-Joachim; Blutke, Andreas; Wanke, Rüdiger; Sauter-Louis, Carola; Duda, Katarzyna A; Holst, Otto; Rainard, Pascal; Germon, Pierre; Zerbe, Holm; Petzl, Wolfram

2015-04-01

The distal compartments of the udder are the first to interact with invading pathogens. The regulatory and effector functions of two major teat regions [Fürstenberg's rosette (FR); teat cistern (TC)] are largely unknown. The objective of this study was to establish an in vitro model with explants of the FR and the TC to analyse their response towards Escherichia coli LPS and Staphylococcus aureus lipoteichoic acid (LTA). Quantitative stereological analysis confirmed differences in the cellular composition of FR and TC explants. Chemokine (CXCL8, CCL5, CCL20) and TNF-α mRNA were expressed at low levels in both locations. Explant stimulation with LPS increased the mRNA abundance of all tested chemokines and TNF-α. Stimulation with LTA only induced CCL20 and CXCL8. LPS- and LTA-stimulated explant supernatants contained CXCL8 and CXCL3. Supernatants significantly attracted neutrophils in vitro. Compared with TC, the FR showed high constitutive mRNA expression of S100 proteins (A8, A9, A12). In the TC, both LPS and LTA significantly induced S100A8, whereas S100A9 and S100A12 expression was only induced by LPS. The novel model system underpins the role of the teat for recognising pathogens and shaping a pathogen- and location-specific immune response. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Prevalence of human papillomavirus infection of the anal canal in women: A prospective analysis of high-risk populations.

PubMed

Kost, Bernd P; Hofmann, Jörg; Stoellnberger, Susanne; Bergauer, Florian; Blankenstein, Thomas; Alba-Alejandre, Irene; Stein, Angela; Stuckart, Claudia; Weizsäcker, Katharina; Mylonas, Ioannis; Mahner, Sven; Gingelmaier, Andrea

2017-04-01

Infection with certain types of human papillomavirus (HPV) has been associated with the development of cervical and anal cancer. Worldwide, the incidence of anal cancer has increased markedly. The present study aimed to evaluate the prevalence of HPV infection of the uterine cervix and anal canal in human immunodeficiency virus (HIV)- and non-HIV-infected risk populations. Cervical and anal HPV swabs and cytology samples were collected from 287 patients at the University Hospital of Munich, Germany between 2011 and 2013. Patients were divided into HIV-negative controls (G1) and two risk groups, including HIV-negative patients with cytological abnormalities of the cervix (G2) and HIV-infected patients (G3). Data, including clinical parameters, were analysed. The risk groups had significantly more positive results for HPV in the anus (71.03 and 83.15% for G2 and G3, respectively), as compared with G1. The predominant HPV genotypes found in the anus were high-risk HPV genotypes, which were significantly correlated with concomittant cervical HPV findings. In the risk groups, a significant association between the cytological findings and HPV detection in the cervix was found, while the results of the anus revealed no significance. The results of the present study suggested that the prevalence of HPV infection in the anal canal of risk populations is high. Furthermore, patients with abnormal cervical cytology results and HIV-infected women, irrespective of their individual cervical findings, may have a risk of concomittant anal high-risk HPV infection. Based on the predominant HPV genotypes found in the study, HPV vaccination could reduce the incidence of anal cancer. Nevertheless, high-risk patients should be intensively screened for anal squamous intraepithelial abnormalities to avoid invasive cancer stages.

Prevalence of human papillomavirus infection of the anal canal in women: A prospective analysis of high-risk populations

PubMed Central

Kost, Bernd P.; Hofmann, Jörg; Stoellnberger, Susanne; Bergauer, Florian; Blankenstein, Thomas; Alba-Alejandre, Irene; Stein, Angela; Stuckart, Claudia; Weizsäcker, Katharina; Mylonas, Ioannis; Mahner, Sven; Gingelmaier, Andrea

2017-01-01

Infection with certain types of human papillomavirus (HPV) has been associated with the development of cervical and anal cancer. Worldwide, the incidence of anal cancer has increased markedly. The present study aimed to evaluate the prevalence of HPV infection of the uterine cervix and anal canal in human immunodeficiency virus (HIV)- and non-HIV-infected risk populations. Cervical and anal HPV swabs and cytology samples were collected from 287 patients at the University Hospital of Munich, Germany between 2011 and 2013. Patients were divided into HIV-negative controls (G1) and two risk groups, including HIV-negative patients with cytological abnormalities of the cervix (G2) and HIV-infected patients (G3). Data, including clinical parameters, were analysed. The risk groups had significantly more positive results for HPV in the anus (71.03 and 83.15% for G2 and G3, respectively), as compared with G1. The predominant HPV genotypes found in the anus were high-risk HPV genotypes, which were significantly correlated with concomittant cervical HPV findings. In the risk groups, a significant association between the cytological findings and HPV detection in the cervix was found, while the results of the anus revealed no significance. The results of the present study suggested that the prevalence of HPV infection in the anal canal of risk populations is high. Furthermore, patients with abnormal cervical cytology results and HIV-infected women, irrespective of their individual cervical findings, may have a risk of concomittant anal high-risk HPV infection. Based on the predominant HPV genotypes found in the study, HPV vaccination could reduce the incidence of anal cancer. Nevertheless, high-risk patients should be intensively screened for anal squamous intraepithelial abnormalities to avoid invasive cancer stages. PMID:28454426

Recent Advances in Root Canal Disinfection: A Review

PubMed Central

Mohammadi, Zahed; Jafarzadeh, Hamid; Shalavi, Sousan; Palazzi, Flavio

2017-01-01

The microbial biofilm is an important factor for human infection. Finding effective antimicrobial strategies should be considered for decreasing antimicrobial resistance and controlling the infectious diseases. Treatment of infected canal systems may not be able to remove all bacteria and so bacterial persistence after treatment may occur. Application of antibacterial nanoparticles may be a potential strategy to improve the elimination of bacteria from the canal. Furthermore, mechanism of action and applications of photodynamic therapy and Photon-induced photoacoustic streaming (PIPS) and GentleWave system was reviewed. PMID:29225632

Correlation between Volume of Apical Periodontitis Determined by Cone-beam Computed Tomography Analysis and Endotoxin Levels Found in Primary Root Canal Infection.

PubMed

Cardoso, Flávia G R; Ferreira, Nádia S; Martinho, Frederico C; Nascimento, Gustavo G; Manhães, Luiz R C; Rocco, Marco A; Carvalho, Cláudio A T; Valera, Marcia C

2015-07-01

This clinical study was conducted to correlate the levels of endotoxins and bacterial counts found in primary endodontic infection with the volume of periapical bone destruction determined by cone-beam computed tomography (CBCT) analysis. Moreover, the levels of bacteria and endotoxins were correlated with the development of clinical features. Twenty-four root canals with primary endodontic disease and apical periodontitis were selected. Clinical features such as pain on palpation, pain on percussion, and previous episode of pain were recorded. The volume (cubic millimeters) of periapical bone destruction was determined by CBCT analysis. Endotoxins and bacterial samplings were collected by using sterile/apyrogenic paper points. Endotoxins were quantified by using limulus amebocyte lysate assay (KQCL test), and bacterial count (colony-forming units [CFU]/mL) was determined by using anaerobic culture techniques. Data were analyzed by Pearson correlation and multiple logistic regression (P < .05). Endotoxins and bacteria were detected in 100% of the root canal samples (24 of 24), with median values of 10.92 endotoxin units (EU)/mL (1.75-128 EU/mL) and 7.5 × 10(5) CFU/mL (3.20 × 10(5)-8.16 × 10(6) CFU/mL), respectively. The median volume of bone destruction determined by CBCT analysis was 100 mm(3) (10-450 mm(3)). The multiple regression analysis revealed a positive correlation between higher levels of endotoxins present in root canal infection and larger volume of bone destruction (P < .05). Moreover, higher levels of endotoxins were also correlated with the presence of previous pain (P < .05). Our findings revealed that the levels of endotoxins found in root canal infection are related to the volume of periapical bone destruction determined by CBCT analysis. Moreover, the levels of endotoxin are related to the presence of previous pain. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Microbiological analysis of infected root canals from symptomatic and asymptomatic teeth with periapical periodontitis and the antimicrobial susceptibility of some isolated anaerobic bacteria.

PubMed

Jacinto, R C; Gomes, B P F A; Ferraz, C C R; Zaia, A A; Filho, F J Souza

2003-10-01

The purpose of the present study was to investigate the correlation between the composition of the bacterial flora isolated from infected root canals of teeth with apical periodontitis with the presence of clinical signs and symptoms, and to test the antibiotic susceptibility of five anaerobic bacteria mostly commonly found in the root canals of symptomatic teeth against various substances using the E-test. Microbial samples were taken from 48 root canals, 29 symptomatic and 19 asymptomatic, using adequate techniques. A total of 218 cultivable isolates were recovered from 48 different microbial species and 19 different genera. Root canals from symptomatic teeth harbored more obligate anaerobes and a bigger number of bacterial species than the asymptomatic teeth. More than 70% of the bacterial isolates were strict anaerobes. Statistical analysis used a Pearson Chi-squared test or a one-sided Fisher's Exact test as appropriate. Suggested relationships were found between specific microorganisms, especially gram-negative anaerobes, and the presence of spontaneous or previous pain, tenderness to percussion, pain on palpation and swelling amoxicillin, amoxicillin + clavulanate and cephaclor were effective against all the strains tested. The lowest susceptibility rate was presented by Prevotella intermedia/nigrescens against Penicillin G. Our results suggested that specific bacteria are associated with endodontic symptoms of infected teeth with periapical periodontitis and the majority of the anaerobic bacterial species tested were susceptible to all antibiotics studied.

Detection of bacteraemias during non-surgicalroot canal treatment.

PubMed

Savarrio, L; Mackenzie, D; Riggio, M; Saunders, W P; Bagg, J

2005-04-01

Some dental procedures initiate a bacteraemia. In certain compromised patients, this bacteraemia may lead to distant site infections, most notably infective endocarditis. To investigate whether a detectable bacteraemia was produced during non-surgical root canal therapy. Thirty patients receiving non-surgical root canal therapy were studied. Three blood samples were taken per patient: pre-operatively, peri-operatively and post-operatively. In addition, a paper point sample was collected from the root canal. The blood samples were cultured by pour plate and blood bottle methods. The isolated organisms were identified by standard techniques. Blood samples were analysed for the presence of bacterial DNA by the polymerase chain reaction (PCR). In two cases where the same species of organism was identified in the root canal and the bloodstream, the isolates were typed by pulsed field gel electrophoresis (PFGE). By conventional culturing, a detectable bacteraemia was present in 9 (30%) of the 30 patients who had no positive pre-operative control blood sample. In 7 (23.3%) patients, the same species of organism was identified in both the bloodstream and in the paper point sample from the root canal system. Overall, PCR gave lower detection rates compared with conventional culture, with 10 of 90 (11%) of the blood samples displaying bacterial DNA. PFGE typing was undertaken for two pairs of culture isolates from blood and paper points; these were found to be genetically identical. Non-surgical root canal treatment may invoke a detectable bacteraemia.

Clinical comparison of the effectiveness of single-file reciprocating systems and rotary systems for removal of endotoxins and cultivable bacteria from primarily infected root canals.

PubMed

Martinho, Frederico C; Gomes, Ana P M; Fernandes, Aletéia M M; Ferreira, Nádia S; Endo, Marcos S; Freitas, Lilian F; Camões, Izabel C G

2014-05-01

This clinical study was conducted to compare the effectiveness of single-file reciprocating systems and rotary systems in removing endotoxins and cultivable bacteria from primarily infected root canals. Forty-eight primarily infected root canals were selected and randomly divided into 4 groups: WaveOne (Dentsply Maillefer, Ballaigues, Switzerland) (n = 12); Reciproc (VDW, Munich, Germany) (n = 12), ProTaper (Dentsply Maillefer) (n = 12), and Mtwo (VDW) (n = 12). Samples were collected before and after chemomechanical preparation. The irrigation was performed by using 2.5% sodium hypochlorite. A chromogenic limulus amebocyte lysate assay test was used to quantify endotoxins. Culture techniques were used to determine bacterial colony-forming unit counts. In the baseline samples (ie, samples collected before chemomechanical preparation), endotoxins and cultivable bacteria were recovered from 100% of the root canal samples. No differences were found in the median percentage values of endotoxin reduction achieved with reciprocating systems (ie, WaveOne [95.15%] and Reciproc [96.21%]) and with rotary systems (ie, ProTaper [97.98%] and Mtwo [96.34%]) (P < .05). Both single-file reciprocating systems (ie, WaveOne [99.45%] and Reciproc [99.93%]) and rotary systems (ProTaper [99.85%] and Mtwo [99.41%]) were effective in reducing the cultivable bacteria (all P < .05). Moreover, the culture analysis revealed no differences in bacterial load reduction (P > .05). Both single-file reciprocating systems (ie, WaveOne and Reciproc instruments) and rotary systems (ie, ProTaper and Mtwo instruments) showed similar effectiveness in reducing endotoxins and cultivable bacteria from primarily infected root canals, but they were not able to eliminate them from all root canals analyzed. Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Ecology of the microbiome of the infected root canal system: a comparison between apical and coronal root segments

PubMed Central

Özok, A.R.; Persoon, I.F.; Huse, S.M.; Keijser, B.J.F.; Wesselink, P.R.; Crielaard, W.; Zaura, E.

2016-01-01

Aim To evaluate the microbial ecology of the coronal and apical segments of infected root canal systems using a complete sampling technique and next-generation sequencing. Methodology The roots of 23 extracted teeth with apical periodontitis were sectioned in half, horizontally, and cryo-pulverized. Bacterial communities were profiled using tagged 454 pyrosequencing of the 16S rDNA hypervariable V5–V6 region. Results The sequences were classified into 606 taxa (species or higher taxon), representing 24 bacterial phyla or candidate divisions and one archaeal phylum. Proteobacteria were more abundant in the apical samples (p<0.05), while Actinobacteria were in significantly higher proportions in the coronal samples. The apical samples harbored statistically significantly more taxa than the coronal samples (p=0.01), and showed a higher microbial diversity. Several taxa belonging to fastidious obligate anaerobes were significantly more abundant in the apical segments of the roots compared to their coronal counterparts. Conclusions Endodontic infections are more complex than reported previously. The apical part of the root canal system drives the selection of a more diverse and more anaerobe community than the coronal part. The presence of a distinct ecological niche in the apical region explains the difficulty of eradication of the infection, and emphasizes the need that new treatment approaches should be developed. PMID:22251411

Microbial contamination of the environment after the irradiation of Er:YAG laser in infected root canals

NASA Astrophysics Data System (ADS)

Brugnera, Aldo, Jr.; Zanin, Fatima A. A.; Sampaio Moura, Marcelo; Heredia Seixas, Fabio; Rodrigues de Araujo Estrela, Cyntia; Estrela, Carlos; Djalma Pecora, Jesus

2003-06-01

The purpose of this study was to analyze the environment microbial contamination produced by Er:YAG laser irradiation in infected root canals. A total of 20 human anterior teeth were prepared, sterilized and, then, inoculated with a mixture of the following microorganisms: S. Aureus, E. Faecalis, P. Aeruginosa, B. Subtilis and C. Albicans. After the contamination period (28 days), the teeth were irrigated with sterile distilled water or 1% sodium hypochlorite and, then, irradiated with an Er:YAG laser with two different laser parameters: 52 mJ or 110 mJ output at the fiber tip. Eighteen Petri dishes with 20 ml of BHI Agar were used in the study. For each group, 3 plates with BHIA were used for the analysis of the microbial contamination of the environment during the activation of the laser in infected root canals. The plates were positioned in differing distances away from the irradiated tooth (plate 1 - distance of 15 cm, plate 2 - distance of 50 cm and plate 3 - distance of 3 meters). After the analysis of the results, it was observed that the larger microbial contamination occurred in Group 1 (teeth irrigated with sterile distilled water and irradiated with Er:YAG laser with 52 mJ output at the fiber tip), plate 1 (positioned 15 cm away from the irradiated tooth), with values greater than 30 Colony-Forming Units (CFU).

Evaluation of the bactericidal effect of Nd:YAG, Er:YAG, Er,Cr:YSGG laser radiation, and antimicrobial photodynamic therapy (aPDT) in experimentally infected root canals.

PubMed

Cheng, Xiaogang; Guan, Sumin; Lu, Hong; Zhao, Chunmiao; Chen, Xingxing; Li, Na; Bai, Qian; Tian, Yu; Yu, Qing

2012-12-01

In recent years, various laser systems have been introduced into the field of laser-assisted endodontic therapy. The aim of this study was to evaluate the bactericidal effect of Nd:YAG, Er:YAG, Er,Cr:YSGG laser radiation, and antimicrobial photodynamic therapy (aPDT) in experimentally infected root canals compared with standard endodontic treatment of 5.25% sodium hypochlorite (NaClO) irrigation. Two hundred and twenty infected root canals from extracted human teeth (contaminated with Enterococcus faecalis ATCC 4083 for 4 weeks) were randomly divided into five experimental groups (Nd:YAG, Er:YAG + 5.25% NaClO + 0.9% normal saline + distilled water (Er:YAG/NaClO/NS/DW), Er:YAG + 0.9% normal saline + distilled water (Er:YAG/NS/DW), Er,Cr:YSGG, and aPDT) and two control groups (5.25% NaClO as positive control and 0.9% normal saline (NS) as negative control). The numbers of bacteria on the surface of root canal walls and at different depths inside dentinal tubules before and after treatment were analyzed by means of one-way analysis of variance (one-way ANOVA). The morphology of bacterial cells before and after treatment was examined by scanning electron microscopy (SEM). After treatment, the bacterial reductions in the experimental groups and the positive control group were significantly greater than that of the negative control group (P < 0.001). However, only Er:YAG/NaClO/NS/DW group showed no bacterial growth (the bacterial reduction reached up to 100%) on the surface of root canal walls or at 100/200 µm inside the dentinal tubules. All the laser radiation protocols tested, especially Er:YAG/NaClO/NS/DW, have effective bactericidal effect in experimentally infected root canals. Er:YAG/NaClO/NS/DW seems to be an ideal protocol for root canal disinfection during endodontic therapy. Copyright © 2012 Wiley Periodicals, Inc.

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

PubMed

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.

Structural equation models to estimate risk of infection and tolerance to bovine mastitis.

PubMed

Detilleux, Johann; Theron, Léonard; Duprez, Jean-Noël; Reding, Edouard; Humblet, Marie-France; Planchon, Viviane; Delfosse, Camille; Bertozzi, Carlo; Mainil, Jacques; Hanzen, Christian

2013-03-06

One method to improve durably animal welfare is to select, as reproducers, animals with the highest ability to resist or tolerate infection. To do so, it is necessary to distinguish direct and indirect mechanisms of resistance and tolerance because selection on these traits is believed to have different epidemiological and evolutionary consequences. We propose structural equation models with latent variables (1) to quantify the latent risk of infection and to identify, among the many potential mediators of infection, the few ones that influence it significantly and (2) to estimate direct and indirect levels of tolerance of animals infected naturally with pathogens. We applied the method to two surveys of bovine mastitis in the Walloon region of Belgium, in which we recorded herd management practices, mastitis frequency, and results of bacteriological analyses of milk samples. Structural equation models suggested that, among more than 35 surveyed herd characteristics, only nine (age, addition of urea in the rations, treatment of subclinical mastitis, presence of dirty liner, cows with hyperkeratotic teats, machine stripping, pre- and post-milking teat disinfection, and housing of milking cows in cubicles) were directly and significantly related to a latent measure of bovine mastitis, and that treatment of subclinical mastitis was involved in the pathway between post-milking teat disinfection and latent mastitis. These models also allowed the separation of direct and indirect effects of bacterial infection on milk productivity. Results suggested that infected cows were tolerant but not resistant to mastitis pathogens. We revealed the advantages of structural equation models, compared to classical models, for dissecting measurements of resistance and tolerance to infectious diseases, here bovine mastitis. Using our method, we identified nine major risk factors that were directly associated with an increased risk of mastitis and suggested that cows were tolerant but

A teat papillomatosis case in a Damascus goat (Shami goat) in Hatay province, Turkey: a new putative papillomavirus?

PubMed

Dogan, Fırat; Dorttas, Selvi Deniz; Bilge Dagalp, Seval; Ataseven, Veysel Soydal; Alkan, Feray

2018-06-01

Papillomaviruses (PVs) are epitheliotropic viruses that cause benign proliferative lesions in the skin (warts or papillomas) and mucous membranes of their natural hosts. Recently, new PVs have been found in many animal species. The most common current approach for identifying novel PV types is based on PCR, using various consensus or degenerated primer (broad-range primers), designed on the basis of the multiple alignment of nucleotide or amino acid sequences of a large number of different human papillomaviruses (HPV). PVs have been classified according to the sequence similarity of one of their capsid proteins, L1, without taking into account other regions of the genome and without considering the phenotypic characteristics of the viral infection. In this study, we performed molecular detection and typing of a PV in a goat with teat papillomatosis. Firstly, PCR was performed using the FAP59/FAP64 and MY09/MY11 primer pairs for the L1 gene region. The PV DNA was found to be positive only with the FAP59/FAP64 primer pair. PV DNA was then tested with three primer sets in four different combinations (L2Bf/FAP64, L2Bf/L1Br, FAP59/FAP64, L1Bf/LCRBr) for the gene region encoding the L1, L2 and LCR proteins. The goat teat papilloma sample was amplified using FAP59/FAP64 primers and two primer pairs (L2Bf/FAP64 and L2Bf/L1Br). We obtained products matching approximately 604 bp of the L1 region of the virus. PV DNA was used for typing using sequence analysis/PCR with some type-specific primers for bovids, caprids and cervids. The results of the sequence analysis suggested one new putative PV type with sequence identity ranging from 46.45 to 80.09% to other known papillomaviruses, including Capra hircus papillomavirus (ChPV-2), bovine papillomavirus (BPV) 6, 7, 10, 11 and 12, Rangifer tarandus papillomavirus 3 (RtPV-3) and BPV-7Z (Alpine wild ruminant papillomavirus; Cervus elaphus papillomavirus). We therefore propose that this is the first identification of a new putative

Reduction in bacterial counts in infected root canals after rotary or hand nickel-titanium instrumentation--a clinical study.

PubMed

Rôças, I N; Lima, K C; Siqueira, J F

2013-07-01

To compare the antibacterial efficacy of two instrumentation techniques, one using hand nickel-titanium (NiTi) instruments and the other using rotary NiTi instruments, in root canals of teeth with apical periodontitis. Root canals from single-rooted teeth were instrumented using either hand NiTi instruments in the alternated rotation motion technique or rotary BioRaCe instruments. The irrigant used in both groups was 2.5% NaOCl. DNA extracts from samples taken before and after instrumentation were subjected to quantitative analysis by real-time polymerase chain reaction (qPCR). Qualitative analysis was also performed using presence/absence data from culture and qPCR assays. Bacteria were detected in all S1 samples by both methods. In culture analysis, 45% and 35% of the canals were still positive for bacterial presence after hand and rotary NiTi instrumentation, respectively (P > 0.05). Rotary NiTi instrumentation resulted in significantly fewer qPCR-positive cases (60%) than hand NiTi instrumentation (95%) (P = 0.01). Intergroup comparison of quantitative data showed no significant difference between the two techniques. There was no significant difference in bacterial reduction in infected canals after instrumentation using hand or rotary NiTi instruments. In terms of incidence of positive results for bacteria, culture also showed no significant differences between the groups, but the rotary NiTi instrumentation resulted in more negative results in the more sensitive qPCR analysis. © 2013 International Endodontic Journal. Published by John Wiley & Sons Ltd.

Cytokine expression in response to root canal infection in gnotobiotic mice.

PubMed

Maciel, K F; Neves de Brito, L C; Tavares, W L F; Moreira, G; Nicoli, J R; Vieira, L Q; Ribeiro Sobrinho, A P

2012-04-01

To examine cytokine expression profiles during periapical lesion development in response to synergetic human pathogens in a gnotobiotic mouse model. Human strains of Fusobacterium nucleatum and Peptostreptococcus prevotii were inoculated into the root canals of germ-free mice in either mono- or bi-association. Animals were killed 7 and 14 days after infection, and periapical tissues were collected. mRNA expression of the cytokines IFN-γ, TNF-α, Receptor activator of nuclear factor kappa-B ligand (RANKL), IL-10, IL-4 and transforming growth factor β (TGF-β) was assessed using real-time PCR. Levene's test was used to assess the equality of variance of the data, whereas a t-test for independent samples was used to evaluate the significance of the differences between groups (P < 0.05). The mRNA expression of IFN-γ and TNF-α was up-regulated by F. nucleatum during the acute (day 7) and chronic phase (day 14) of periapical lesion development. However, in bi-infection the expression of IFN-γ and TNF-α were effectively absent at both time-points. RANKL mRNA expression was down-regulated during dual infection at the chronic phase. As IL-4 expression was similar at both time-points, IL-4 does not appear to be involved in the periapical response to these bacterial strains. IL-10 was up-regulated during the chronic phase by mono-infection with either F. nucleatum or P. prevotii. Dual infection increased TGF-β mRNA expression on day 7, which paralleled the decrease in IFN-γ and TNF-α mRNA levels at the same time-point. F. nucleatum increased TGF-β mRNA expression during the chronic phase. Cytokine profiles depend on the nature of the bacterial challenge. Both TGF-β and IL-10 appeared to be regulating the proinflammatory cytokine responses at both time-points of the periapical immune response. © 2012 International Endodontic Journal.

3. ELEVATION. FROM SOUTH WITH CANAL PRISM. Canal Road ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

3. ELEVATION. FROM SOUTH WITH CANAL PRISM. - Canal Road Bridge, Canal Road spanning Delaware Canal Diversion, Locks 22 & 23 in Delaware Canal State Park in Williams Township, Raubsville, Northampton County, PA

[Endodontic microbiology: antimicrobial canal medications].

PubMed

Seltzer, S; Farber, P A

1989-06-01

Medicaments used for reducing or eliminating microorganisms from infected root canals include: irrigating solutions, such as sodium hypochlorite, urea peroxide and hydrogen peroxide, chloramine, iodine-potassium-iodide solution, and chlorhexidine solution. In addition, various intracanal drugs, such as calcium hydroxide and antibiotics, are in use. The characteristics of these drugs are discussed.

[Colonization of Porphyromonas endodontalis in primary and secondary endodontic infections].

PubMed

Hong, Li; Hai, Ji; Yan-Yan, He; Shenghui, Yang; Benxiang, Hou

2015-02-01

This study aims to assess and compare the prevalence of Porphyromonas endodontalis (P. endodontalis) in root canals associated with primary and secondary endodontic infections by using 16s rDNA PCR and real-time fluorescence quantitative polymerase chain reaction (RTFQ-PCR). A total of 120 adult patients with one radiographically documented periapical lesion were included. Sixty teeth presented with primary endodontic infections and 60 with secondary endodontic infections requiring retreatment. P. endodontalis was identified by using 16s rDNA PCR techniques. The positive DNA expression of P. endodontalis in two types of infected root canals were quantitatively compared by using SYBR GREEN I RTFQ-PCR. The prevalence of P. endodontalis in the root canals with primary endodontic infections was significantly higher than that in root canals with secondary endodontic infections (P = 0.001). However, RTFQ-PCR results showed no significant difference in DNA expression quantities between the primary and secondary endodontic infections root canals (P = 0.303). P. endodontalis is more highly associated with root canals having primary endodontic infections, although P. endodontalis colonize in both root canals with primary and secondary chronic apical periodontitis.

Microorganisms isolated from root canals presenting necrotic pulp and their drug susceptibility in vitro.

PubMed

Lana, M A; Ribeiro-Sobrinho, A P; Stehling, R; Garcia, G D; Silva, B K; Hamdan, J S; Nicoli, J R; Carvalho, M A; Farias, L de M

2001-04-01

The knowledge about causative agents involved in endodontic infections is increasing, especially due to the improvement of culture techniques for anaerobic bacteria, showing that these microorganisms are predominant in this pathology. In this study, 31 canals with pulp necrosis were microbiologically analyzed before and after manipulation. Obligate and facultative anaerobes, microaerophilic bacteria and yeasts were recovered from 24, 14, 5 and 2 clinical specimens, respectively. The most frequent genera were Prevotella, Fusobacterium, Lactobacillus, Streptococcus, Clostridium and Peptostreptococcus for bacteria and Candida and Saccharomyces for yeasts. Strong positive associations, using an odds ratio system, were found between Clostridium and Prevotella and between Peptostreptococcus and Fusobacterium. Even after the instrumentation and the use of Ca(OH)2, facultative anaerobes were detected in two root canals and yeasts in three. Microorganisms were isolated from seven canals at the end of the endodontic treatment: facultative anaerobes from five and yeasts from one. The microbiological evaluation of root canals with pulp necrosis suggests the presence of polymicrobial infections, mainly involving obligate anaerobes, and shows that the infection may persist after treatment.

The fluid mechanics of root canal irrigation.

PubMed

Gulabivala, K; Ng, Y-L; Gilbertson, M; Eames, I

2010-12-01

Root canal treatment is a common dental operation aimed at removing the contents of the geometrically complex canal chambers within teeth; its purpose is to remove diseased or infected tissue. The complex chamber is first enlarged and shaped by instruments to a size sufficient to deliver antibacterial fluids. These irrigants help to dissolve dying tissue, disinfect the canal walls and space and flush out debris. The effectiveness of the procedure is limited by access to the canal terminus. Endodontic research is focused on finding the instruments and clinical procedures that might improve success rates by more effectively reaching the apical anatomy. The individual factors affecting treatment outcome have not been unequivocally deciphered, partly because of the difficulty in isolating them and in making the link between simplified, general experimental models and the complex biological objects that are teeth. Explicitly considering the physical processes within the root canal can contribute to the resolution of these problems. The central problem is one of fluid motion in a confined geometry, which makes the dispersion and mixing of irrigant more difficult because of the absence of turbulence over much of the canal volume. The effects of treatments can be understood through the use of scale models, mathematical modelling and numerical computations. A particular concern in treatment is that caustic irrigant may penetrate beyond the root canal, causing chemical damage to the jawbone. In fact, a stagnation plane exists beyond the needle tip, which the irrigant cannot penetrate. The goal is therefore to shift the stagnation plane apically to be coincident with the canal terminus without extending beyond it. Needle design may solve some of the problems but the best design for irrigant penetration conflicts with that for optimal removal of the bacterial biofilm from the canal wall. Both irrigant penetration and biofilm removal may be improved through canal fluid

Comparison of cephalonium alone and in combination with an internal teat sealant for dry cow therapy in seasonally calving dairy cows.

PubMed

Bates, A J; Chambers, G; Laven, R A

2016-03-01

To assess the effect of combining an internal teat sealant (ITS) and a long-acting cephalonium-based dry cow therapy (DCT) on the prevalence of cows with a somatic cell count (SCC) >150,000 cells/mL 60-80 days after calving, and the incidence of clinical mastitis diagnosed by farm staff in the first 100 days after calving. Cows from a spring-calving, pasture-based, dairy farm in the South Canterbury region of New Zealand were randomly allocated to receive cephalonium DCT (n=289) or cephalonium and internal teat sealant (n=304) at the end of lactation. Cows were inspected twice daily by farm staff during the dry period and following calving for signs of mastitis. Individual SCC were determined from herd tests conducted in the previous lactation and following calving. Logistic regression models were used to determine relationships with the prevalence of cows with a SCC >150,000 cells/mL after calving, and survival analysis was used to model time to the first case of clinical mastitis following calving at the cow and quarter level. The OR for a cow with a SCC >150,000 cells/mL after calving, including age and individual SCC in the preceding lactation in the model, was 0.53 (95% CI=0.32-0.89) for cows treated with combination therapy compared to cows receiving cephalonium (p=0.017). At the cow level, including age and preceding SCC in the model, the hazard ratio for diagnosis of clinical mastitis by farm staff in the first 100 days of lactation was 0.60 (95% CI=0.39-0.98) for cows treated with combination therapy compared to cows receiving cephalonium (p=0.04). At the quarter level, the hazard ratio for diagnosis of clinical mastitis, with age included in the model, was 0.41 (95% CI=0.23-0.74) for the combination therapy compared to cephalonium alone (p<0.001). The combination of internal teat sealant and cephalonium DCT was more effective than cephalonium alone at reducing clinical mastitis diagnosed by farm staff in the 100 days after calving, and the prevalence of

Detection of Porphyromonas endodontalis in infected root canals by 16S rRNA gene-directed polymerase chain reaction.

PubMed

Machado de Oliveira, J C; Siqueira, J F; Alves, G B; Hirata, R; Andrade, A F

2000-12-01

Porphyromonas endodontalis has been isolated from the endodontic infections mainly in symptomatic teeth. This study evaluated the occurrence of P. endodontalis in both symptomatic and asymptomatic endodontic infections using 16S rRNA gene-directed polymerase chain reaction. P. endodontalis was detected in 39.5% of the cases (17 of 43 teeth). It was present in 4 of the 6 cases with acute periradicular abscess (66.7%) and in 13 of the 37 other cases (35.1%). The presence of P. endodontalis was associated with an asymptomatic periradicular lesion in 6 cases (25%) and in 10 teeth with tenderness to percussion (52.6%). P. endodontalis was also found in one asymptomatic case without evidence of periradicular pathosis. Our results indicated that, although P. endodontalis is commonly detected in symptomatic cases, it can be present in asymptomatic root canal infections. Further studies should determine if this bacterial species is really an important endodontopathogen.

Root canal treatment and general health: a review of the literature.

PubMed

Murray, C A; Saunders, W P

2000-01-01

The focal infection theory was prominent in the medical literature during the early 1900s and curtailed the progress of endodontics. This theory proposed that microorganisms, or their toxins, arising from a focus of circumscribed infection within a tissue could disseminate systemically, resulting in the initiation or exacerbation of systemic illness or the damage of a distant tissue site. For example, during the focal infection era rheumatoid arthritis (RA) was identified as having a close relationship with dental health. The theory was eventually discredited because there was only anecdotal evidence to support its claims and few scientifically controlled studies. There has been a renewed interest in the influence that foci of infection within the oral tissues may have on general health. Some current research suggests a possible relationship between dental health and cardiovascular disease and published case reports have cited dental sources as causes for several systemic illnesses. Improved laboratory procedures employing sophisticated molecular biological techniques and enhanced culturing techniques have allowed researchers to confirm that bacteria recovered from the peripheral blood during root canal treatment originated in the root canal. It has been suggested that the bacteraemia, or the associated bacterial endotoxins, subsequent to root canal treatment, may cause potential systemic complications. Further research is required, however, using current sampling and laboratory methods from scientifically controlled population groups to determine if a significant relationship between general health and periradicular infection exists.

Panama Canal : a new course for the canal

DOT National Transportation Integrated Search

1999-01-01

While the Panama Canal provides significant time savings, passage through this narrow waterway presents a host of challenges. Soon all canal pilots will have a new tool in their efforts to safely guide vessels through this difficult canal: a Communic...

2. CANAL BOAT ENTERING THE DELAWARE CANAL FROM OF THE ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

2. CANAL BOAT ENTERING THE DELAWARE CANAL FROM OF THE LEHIGH RIVER. BOATS COULD BE FERRIED ACROSS THE DELAWARE RIVER TO THE MORRIS CANAL BY A CABLE SUPPORTED TROLLEY. - Morris Canal, Phillipsburg, Warren County, NJ

Antimicrobial effect of Er:YAG laser irradiation in infected root canals: an in vitro study

NASA Astrophysics Data System (ADS)

Sampaio Moura, Marcelo; Zanin, Fatima A. A.; Brugnera, Aldo, Jr.; Rodrigues de Araujo Estrela, Cyntia; Estrela, Carlos; Djalma Pecora, Jesus

2003-06-01

This study evaluated in vitro the antimicrobial action of Er:YAG laser in infected root canals. A total of 36 human anterior teeth were prepared, sterilized and inoculated with suspensions of S. aureus, E. faecalis, P aeruginosa, B. subtilis and C. albicans. After the contamination period (28 days), the teeth were irrigated with sterile distilled water or 1% sodium hypochlorite and, then, irradiated with an Er:YAG laser (wavelength 2094 nm) with two different evaluation parameters: 52 mJ and 110 mJ laser output at the fiber tip. After the irradiation, the teeth were irrigated with sterile distilled water and the solutions were collected with sterile paper points and incubated in Letheen Broth for 48 hours. After this period 0,1 ml of this solution was transferred to 10 ml of Brain Heart Infusion and incubated for 48 hours. After 72 hours a new collect ion was done and incubated again. Based on the data, it was concluded that the distilled water or 1% sodium hypochlorite irradiated or not with an Er:YAG laser with two different parameters: 10 Hz, 110 mJ input and 52 mJ output, and 10 Hz, 250 mJ input and 110 mJ output had no antimicrobial activity in the root canals contaminated with the following microorganisms: Enterococcus faecalis, Staphylococcus aureus, Pseudomonas aeruginosa, Bacillus subtilis and Candida albicans.

27. VIEW OF TWIN FALLS MAIN CANAL HEADGATE WITH CANAL ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

27. VIEW OF TWIN FALLS MAIN CANAL HEADGATE WITH CANAL BRIDGE IN DISTANCE; LOOKING SOUTHWEST. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

14. MAIN CANAL CANAL CHECKGATES, JUST BELOW DARK CANYON ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

14. MAIN CANAL - CANAL CHECKGATES, JUST BELOW DARK CANYON SIPHON, VIEW TO NORTHEAST - Carlsbad Irrigation District, Main Canal, 4 miles North to 12 miles Southeast of Carlsbad, Carlsbad, Eddy County, NM

Analysis of symptomatic and asymptomatic primary root canal infections in adult Norwegian patients.

PubMed

Rôças, Isabela N; Siqueira, José F; Debelian, Gilberto J

2011-09-01

This molecular study analyzed the microbiota of primary root canal infections from adult Norwegian patients. Samples were taken from the necrotic root canals of teeth with symptomatic (n = 13) or asymptomatic (n = 21) apical periodontitis and chronic apical abscesses (n = 9). DNA was extracted from samples, and bacterial identifications were performed by a closed-ended reverse-capture checkerboard approach targeting 50 candidate endodontic pathogens. Bacterial DNA was detected in all cases. In teeth with asymptomatic apical periodontitis, the most frequent taxa were Dialister invisus (71%), Fusobacterium nucleatum (62%), and Porphyromonas endodontalis (62%). In chronic apical abscesses, the most prevalent taxa were P. endodontalis (100%), D. invisus (89%), Parvimonas micra (78%), and Solobacterium moorei (78%). In teeth with symptomatic apical periodontitis, the most prevalent taxa were D. invisus, P. endodontalis, S. moorei, Propionibacterium acnes, and Streptococcus species (all in 69%). None of the targeted taxa were significantly associated with either sinus tract or pain (P > .05), except for Selenomonas sputigena, which was more frequently found in painful cases (P = .04). No taxa were found in significantly higher levels in any conditions (P > .05). Cluster analyses revealed bacterial groupings that differed between cases with and without pain. Although basically the same species were highly prevalent in the different conditions examined and none of the most prevalent taxa were positively associated with symptoms, results revealed that species formed different partnerships and associations in samples from teeth with or without pain. Therefore, it is possible that more virulent multispecies communities can form as a result of overall bacterial combinations and give rise to acute inflammation. Copyright © 2011 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

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

PubMed Central

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

Characterization of Actinomyces Isolates from Infected Root Canals of Teeth: Description of Actinomyces radicidentis sp. nov.

PubMed Central

Collins, Matthew D.; Hoyles, Lesley; Kalfas, Sotos; Sundquist, Goran; Monsen, Tor; Nikolaitchouk, Natalia; Falsen, Enevold

2000-01-01

Two strains of a previously undescribed Actinomyces-like bacterium were recovered in pure culture from infected root canals of teeth. Analysis by biochemical testing and polyacrylamide gel electrophoresis of whole-cell proteins indicated that the strains closely resembled each other phenotypically but were distinct from previously described Actinomyces and Arcanobacterium species. Comparative 16S rRNA gene-sequencing studies showed the bacterium to be a hitherto unknown subline within a group of Actinomyces species which includes Actinomyces bovis, the type species of the genus. Based on phylogenetic and phenotypic evidence, we propose that the unknown bacterium isolated from human clinical specimens be classified as Actinomyces radicidentis sp. nov. The type strain of Actinomyces radicidentis is CCUG 36733. PMID:10970390

8. BLACK RIVER CANAL LOOKING DOWN CANAL WITH LATERAL ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

8. BLACK RIVER CANAL - LOOKING DOWN CANAL WITH LATERAL TURNOUT NO. 1 ON THE RIGHT. VIEW TO THE SOUTHEAST - Carlsbad Irrigation District, Black River Canal, 15 miles Southeast of Carlsbad near Malaga, Carlsbad, Eddy County, NM

9. BLACK RIVER CANAL CANAL (RIGHT), DISCHARGE GATE (BACKGROUND), ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

9. BLACK RIVER CANAL - CANAL (RIGHT), DISCHARGE GATE (BACKGROUND), FARMER'S TURNOUT (LEFT), AND LATERAL NO. 14 (FOREGROUND). VIEW TO SOUTHEAST - Carlsbad Irrigation District, Black River Canal, 15 miles Southeast of Carlsbad near Malaga, Carlsbad, Eddy County, NM

Pathogen group specific risk factors for clinical mastitis, intramammary infection and blind quarters at the herd, cow and quarter level in smallholder dairy farms in Jimma, Ethiopia.

PubMed

Tolosa, T; Verbeke, J; Ayana, Z; Piepers, S; Supré, K; De Vliegher, S

2015-07-01

A cross-sectional study on clinical mastitis, intramammary infection (IMI) and blind quarters was conducted on 50 smallholder dairy farms in Jimma, Ethiopia. A questionnaire was performed, and quarters of 211 cows were sampled and bacteriologically cultured. Risk factors at the herd, cow, and quarter level for clinical mastitis and (pathogen-specific) intramammary infection were studied using multilevel modeling. As well, factors associated with quarters being blind were studied. Eleven percent of the cows and 4% of the quarters had clinical mastitis whereas 85% of the cows and 51% of the quarters were infected. Eighteen percent of the cows had one or more blind quarter(s), whereas 6% of the quarters was blind. Non-aureus staphylococci were the most frequently isolated pathogens in both clinical mastitis cases and IMI. The odds of clinical mastitis was lower in herds where heifers were purchased in the last year [odds ratio (OR) with 95% confidence interval: 0.11 (0.01-0.90)], old cows (>4 years) [OR: 0.45 (0.18-1.14)], and quarters not showing teat injury [OR: 0.23 (0.07-0.77)]. The odds of IMI caused by any pathogen was higher in herds not practicing teat drying before milking (opposed to drying teats with 1 towel per cow) [OR: 1.68 (1.05-2.69)], cows in later lactation (>180 DIM opposed to ≤90 DIM) [OR: 1.81 (1.14-2.88)], cows with a high (>3) body condition score (BCS) [OR: 1.57 (1.06-2.31)], right quarters (opposed to a left quarter position) [OR: 1.47 (1.10-1.98)], and quarters showing teat injury [OR: 2.30 (0.97-5.43)]. Quarters of cows in herds practicing bucket-fed calf feeding (opposed to suckling) had higher odds of IMI caused by Staphylococcus aureus [OR: 6.05 (1.31-27.90)]. Except for BCS, IMI caused by non-aureus staphylococci was associated with the same risk factors as IMI caused by any pathogen. No access to feed and water immediately after milking [OR: 2.41 (1.26-4.60)], higher parity [OR: 3.60 (1.20-10.82)] and tick infestation [OR: 2.42 (1

Microbial profile of root canals of primary teeth with pulp necrosis and periradicular lesion.

PubMed

Triches, Thaisa Cezária; de Figueiredo, Luciene Cristina; Feres, Magda; de Freitas, Sérgio Fernando Torres; Zimmermann, Gláucia Santos; Cordeiro, Mabel Mariela Rodríguez

2014-01-01

The purpose of this study was to assess the microbial content of root canals of human primary teeth with pulp necrosis and periradicular lesion. Microbial samples were collected from 24 canals of children treated at a pediatric dentistry clinic. Microbiological identification was performed using checker-board DNA-DNA hybridization for 40 different bacteria. Data were analyzed per canal based on the mean count and frequency of each bacterial species. Detectable levels of bacterial species were observed for 35 probes (88%). The most frequent bacteria were Fusobacterium nucleatum sp. nucleatum, Fusobacterium periodonticum, Prevotella melaninogenica, Prevotella nigrescens, and Prevotella intermedia. Facultative species were identified in 20 root canals (83%), anaerobic species were identified in 24 root canals (100%), and aerobic species in 18 root canals (75%). Black-pigmented bacilli were found in 23 samples (96%). The number of different bacterial species detected per canal ranged from five to 33. Endodontic infection in primary teeth with pulp necrosis and periradicular lesion is multimicrobial, including aerobic, facultative, and anaerobic micro-organisms.

Canal transportation after root canal instrumentation: a comparative study with computed tomography.

PubMed

Hartmann, Mateus Silveira Martins; Barletta, Fernando Branco; Camargo Fontanella, Vânia Regina; Vanni, José Roberto

2007-08-01

This in vitro study used computed tomography (CT) to compare the occurrence of canal transportation in the apical third of mesiobuccal canals in maxillary molars instrumented with 3 techniques. Sixty teeth were assigned to 3 groups (n = 20), and the root canals were instrumented as follows: Group 1, hand instrumentation with K-files; Group 2, K-files coupled to an oscillatory system powered by an electric engine; Group 3, ProTaper NiTi rotary system powered by an electric engine. To compare the canal transportation produced by the different techniques, preinstrumentation and postinstrumentation 3-dimensional CT images were obtained from root cross-sections of the region located 3 mm short of the apical foramen of each root canal. The CT scans were exported to Adobe Photoshop software, and the initial and final images were superimposed to detect the root canal wall differences between them. Canal transportation was measured by the distance between the prepared canal center and the anatomic canal center. The manual technique produced lesser canal transportation (0.10 mm) than the oscillatory and rotary techniques (0.37 and 0.22 mm, respectively); this difference was statistically significant (P=.021). All studied techniques produced canal transportation.

Root canal irrigants

PubMed Central

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 discussed. We performed a Medline search for English-language papers published untill July 2010. The keywords used were ‘root canal irrigants’ and ‘endodontic irrigants.’ The reference lists of each article were manually checked for additional articles of relevance. PMID:21217955

Quantification of endotoxins in infected root canals and acute apical abscess exudates: monitoring the effectiveness of root canal procedures in the reduction of endotoxins.

PubMed

Sousa, Ezilmara L R; Martinho, Frederico C; Nascimento, Gustavo G; Leite, Fabio R M; Gomes, Brenda P F A

2014-02-01

This clinical study was conducted to measure the endotoxin levels in infected root canals (RCs) and exudates related to acute apical abscesses (AAAs). In addition, the effectiveness of RC procedures in reducing the endotoxin levels in RCs was monitored. Paired samples of infected RCs and exudates from AAAs were collected from 10 subjects by using paper points. RCs samples were collected before (RCS1) and after chemomechanical preparation (CMP) (RCS2), after 17% EDTA (RCS3), and after 30 days of intracanal medication (Ca[OH]2 + chlorhexidine) (RCS4). A turbidimetric kinetic limulus amebocyte lysate assay was used for the measurement of endotoxins. Endotoxins were detected in 100% of the baseline samples of AAAs and RCs (RCS1) with median values of 175 EU/mL and 41.5 EU/mL, respectively (P < .05). After CMP (RCS2), endotoxins were reduced to a median value of 0.54 EU/mL (P < .05). Subsequent irrigation with EDTA (RCS3) failed to present a significant effectiveness in reducing the endotoxin levels (median= 0.37 EU/mL) (P = .07). However, intracanal medication for 30 days (RCS4) reduced endotoxins to median values of 0.03 EU/mL (P < .01). The present study revealed a strong association between the high levels of endotoxins found in AAAs and RCs collected from the same tooth. Moreover, the effectiveness of CMP in reducing the endotoxin levels from RCs in acute endodontic infection was improved by the use of RC medication. Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Prevalence of Enterococcus faecalis and Porphyromonas gingivalis in infected root canals and their susceptibility to endodontic treatment procedures: a molecular study.

PubMed

Stojanović, Nikola; Krunić, Jelena; Popović, Branka; Stojičić, Sonja; Zivković, Slavoljub

2014-01-01

Because apical periodontitis is recognizably an infectious disease, elimination or reduction of intracanal bacteria is of utmost importance for optimum treatment outcome. The prevalence of Enterococcus faecalis and Porphyromonas gingivalis in infected root canals was studied Also, the effect of endodontic therapy by using intracanal medicaments, calcium hydroxide paste (CH) or gutta-percha points containing calcium hydroxide (CH-GP) or chlorhexidine (CHX-GP) on these microorganisms was assessed by polymerase chain reaction (PCR) assay. Fifty-one patients with chronic apical periodontitis were randomly allocated in one of the fol- lowing groups according to the intracanal medicament used: CH, CH-GP and CHX-GP group. Bacterial samples were taken upon access (S1), after chemomechanical instrumentation (S2) and after 15-day medication (S3). PCR assay was used to detect the presence of selected bacteria. E. faecalis was detected in 49% (25/51) and P. gingivalis in 17.6% (9/51) of the samples. Samples which showed no bacterial presence at S1 were excluded from further analysis. Overall analysis of all 29 samples revealed significant differences between S1 and S2 (p < 0.001), S2 and S3 (p < 0.05), and S1 and S3 (p < 0.001). When distinction was made between the intracanal medications, there was a significant difference in the number of PCR positive samples between S1 and 52, S1 and S3, but not between S2 and S3 samples. E. faecalis is more prevalent than P. gingivalis in primary endodontic infection. Intracanal medication in conduction with instrumentation and irrigation efficiently eliminates E. faecalis and P. gingivalis from infected root canals.

Canals

ERIC Educational Resources Information Center

Winkleman, Michael

1974-01-01

In the mid-1800's, the canal system in the U.S. was thriving. But, by the end of that century, roads and railways had replaced these commercial thoroughfares. Renewed interest in the abandoned canals is now resulting in renovation and ecological site development in Pennsylvania and New Jersey. (MA)

Evaluation of the association between fecal excretion of Mycobacterium avium subsp paratuberculosis and detection in colostrum and on teat skin surfaces of dairy cows

USDA-ARS?s Scientific Manuscript database

Objective—To evaluate the association between fecal excretion of Mycobacterium avium subsp paratuberculosis (MAP) by dairy cows in the periparturient period and detection of MAP DNA in colostrum specimens and on teat skin surfaces. Design—Cross-sectional study. Animals—112 Holstein cows. Procedures—...

A comparison of the effect of short-acting and long-acting cloxacillin-based dry-cow therapy on somatic cell counts after calving in cows also given internal teat sealants.

PubMed

Whitfield, L K; Laven, R A

2018-01-01

To compare, in cows treated with an internal teat sealant, the effect of short-acting and long-acting cloxacillin-based dry-cow therapy on somatic cell counts (SCC) after calving. Cows from a spring-calving, pasture-based dairy farm in the Manawatu-Whanganui region of New Zealand were randomly allocated to receive either a short-acting cloxacillin and ampicillin dry-cow therapy and internal teat sealant (n=291) or a long-acting cloxacillin and ampicillin dry-cow therapy and internal teat sealant (n=288) at the end of lactation. Cows were managed on-farm with routine husbandry procedures through the dry period and following calving. A multivariable logistic regression model was used to determine the association between length of action of dry-cow therapy and the proportion of cows with a SCC >150,000 cells/mL at the first herd test after calving. Age of cow, mean SCC for the preceding season and interval from calving to the first post-calving herd test were all associated with the proportion of cows with an individual SCC >150,000 cells/mL at the first herd test (p<0.001) Treatment with the short-acting dry-cow therapy was not associated with decreased odds of cows having a SCC >150,000 cells/mL at the first herd test compared with treatment with long-acting dry-cow therapy (OR=0.724; 95% CI=0.40-1.30). In this herd, which routinely used internal teat sealants, the use of short-acting cloxacillin-based dry-cow therapy did not result in an increased proportion of cows with elevated SSC post-calving. This was a single farm, single year study but indicates that in this herd, changing from a long-acting to a short-acting antimicrobial may have no impact on the prevalence of subclinical mastitis.

7. 'FLOW IN CANAL NO. 1, A JOINTLY USED CANAL, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

7. 'FLOW IN CANAL NO. 1, A JOINTLY USED CANAL, ON MAY 22 WHEN 210 SECOND FEET OF WATER WAS FLOWING. THIS WAS LATER INCREASED TO 240 SECOND FEET FOR A NUMBER OF DAYS TO SATISFY THE DEMANDS OF THE DRY GULCH COMPANY.' 1925 - Irrigation Canals in the Uinta Basin, Duchesne, Duchesne County, UT

Disinfection of Contaminated Canals by Different Laser Wavelengths, while Performing Root Canal Therapy

PubMed Central

Asnaashari, Mohammad; Safavi, Nassimeh

2013-01-01

Removal of smear layer and disinfection of canals are important objectives of teeth root canal cleaning. In order to achieve this purpose, rinsing substances, intra canal drugs as well as ultrasound are used. Today, use of laser to remove smear layer and to disinfect root canals has increasingly attracted the attentions. Till now different lasers such as CO2, Nd:YAG, Er:YAG, Er,Cr:YSGG have been used for debris and smear removal from the canals. Numerous studies have shown that Er:YAG is the most appropriate laser for intra canal debris and smear removal. In addition different laser wavelengths have been used directly or as an adjunctive to disinfect canals. Laser light can penetrate areas of canals where irrigating and disinfecting solutions cannot reach, like secondary canals and deep dentinal tubules and also can eliminate microorganisms. Different studies have confirmed the penetration of Nd:YAG laser in deep dentin and reduction of microorganisms penetration. But studies on comparison of antibacterial effects of Nd:YAG laser with sodium hypochlorite showed effectiveness of both, with a better effect for sodium hypochlorite. Studies performed in relation with anti-microbial effects of Diode laser with various parameters show that this laser can be effective in reducing intra canal bacterial count and penetration in the depth of 500 microns in dentin. In studies performed on Diode laser in combination with canal irrigating solutions such as sodium hypochlorite and oxygenated water better results were obtained. Although studies on disinfection by the Erbium laser family show that use of this laser alone can be effective in disinfecting canals, studies evaluating the disinfecting effects of this laser and different concentrations of sodium hypochlorite show that the latter alone is more effective in disinfecting canals. And better results were obtained when Erbium laser was used in combination with sodium hypochlorite irrigating solution in canals. Results of the

Associations of soft flooring materials in free stalls with milk yield, clinical mastitis, teat lesions, and removal of dairy cows.

PubMed

Ruud, L E; Bøe, K E; Osterås, O

2010-04-01

The objective was to test if there was an association between free-stall base softness and milk yield, incidence of clinical mastitis (CM), teat lesions, and removal of cows. In a questionnaire sent to 1,923 dairy farms presumed to be using free-stall housing, farmers were asked for information regarding housing and stall base; for example, the year of installation and the product name or brand of their mats or mattresses. This information was merged with data for milk yield, CM, teat lesions, and removal of cows extracted from the Norwegian Dairy Herd Recording System for the years after installation of mats or mattresses. After exclusion of invalid contributions, the data set consisted of 29,326 lactations for milk yield distributed over 363 free-stalled herds in Norway. The farms were stratified into 5 categories according to the softness of the stall surface measured as millimeter impact of a sphere with a diameter of 120 mm at 2-kN load: 1=concrete, softness of 0mm; 2=rubber, softness of 1 to 8mm; 3=soft mats, softness of 9 to 16 mm; 4=multilayer mats, softness of 17 to 24 mm; and 5=mattresses, softness over 24 mm. Lactation curves were estimated as modified Wood's lactation curves using test-day data and mixed models with repeated measurements, adjusting for days in milk, parity, and softness of free-stall flooring. Herds on concrete free-stall bases yielded 6,727+/-146 kg of milk from 5 to 305 days in milk. In comparison, herds showed a decrease of 0.3% on rubber, an increase of 2.4% on soft mats, an increase of 4.5% on multilayer mats, and an increase of 3.9% on mattresses. Compared with concrete, the hazard ratio (HR) of CM was less on rubber, multilayer mats, and mattresses [HR=0.89 (0.79-0.99), 0.85 (0.73-0.996), and 0.80 (0.73-0.88), respectively]. Compared with concrete, the HR of teat lesions was less on rubber, soft mats, multilayer mats, and mattresses [HR=0.41 (0.26-0.65), 0.33 (0.24-0.44), 0.12 (0.04-0.38), and 0.47 (0.33-0.67), respectively]. The

The Effect of Gaseous Ozone in Infected Root Canal

PubMed Central

Ajeti, Nova Nexhmije; Pustina-Krasniqi, Teuta; Apostolska, Sonja

2018-01-01

OBJECTIVES: During the treatment of chronic apical periodontitis and pulp necrosis the main role is to irrigate the root canal. AIM: The aim of this in vivo study was to irrigate with 0.9% NaCl (Natrium Chloride), 2.5 % NaOCl (Sodium Hypochlorite Solution, Sigma Aldrich - Germany) and 2% CHX (Chlorhexidine Digluconate Solution, Sigma Aldrich - Spain) combined with Gaseous Ozone (Prozone WH, Austria). MATERIAL AND METHODS: This study was realised in the University Dentistry Clinical Centre of Kosovo (UDCCK), respectively in the Department of Endodontic and Dental Pathology, Dental Branch, Faculty of Medicine, Prishtina, Kosovo. The 40 subjects involved in this study belonged to both genders, in age between 15 -65 years. The sample selection was randomised. The retroalveolar radiography for each patient was taken in the suspected tooth. As a therapeutic plan the authors decided to disinfect the root canal with the irrigants, as follows: 2.5 % NaOCl, 2 % CHX and gaseous ozone. RESULTS: The statistical analyses were based on Kruskal - Vallis test, X - test, DF = 3, r < 0.01. In the isolated average number of the aerobe and anaerobe bacteria colonies, when gaseous ozone was used, there was the significant statistical difference. CONCLUSIONS: When gaseous ozone was combined with irrigants 0.9%, 2.5 % NaOCl and 2% CHX, it was concluded that the number of colonies of aerobic and anaerobic bacteria was reduced. PMID:29531611

Antibacterial properties of silver nanoparticles as a root canal irrigant against Enterococcus faecalis biofilm and infected dentinal tubules.

PubMed

Rodrigues, C T; de Andrade, F B; de Vasconcelos, L R S M; Midena, R Z; Pereira, T C; Kuga, M C; Duarte, M A H; Bernardineli, N

2018-02-03

To evaluate the antimicrobial action of an irrigant containing silver nanoparticles in an aqueous vehicle (AgNp), sodium hypochlorite and chlorhexidine against Enterococcus faecalis biofilm and infected dentinal tubules. Bovine dentine blocks were used for E. faecalis biofilm development for 21 days and irrigated with 94 ppm AgNp solution, 2.5% NaOCl and 2% chlorhexidine for 5, 15 and 30 min. For infection of dentinal tubules with E. faecalis, dentine specimens from bovine incisors were submitted to a contamination protocol over 5 days, with eight centrifugation cycles on every alternate day, and irrigated with the same solutions and time intervals used for the biofilm. The specimens were stained with the Live/Dead technique and evaluated using a confocal laser scanning microscope (CLSM). The bioImage_L software was used for measurement of the total biovolume of biofilm in μm 3 and percentage of viable bacteria (green cells) in biofilm and in dentinal tubules found after the irrigation. Statistical analyses were performed using Kruskal-Wallis and Dunn's tests for quantification of viable cells in biofilm, the Friedman test for comparisons of viable bacteria in dentinal tubules in different areas of the root canal and the Mann-Whitney U-test to compare the action of the irrigants between the two methods (P < 0.05). The AgNp solution eliminated fewer bacteria, but was able to dissolve more biofilm compared with chlorhexidine (P < 0.05). NaOCl had the greatest antimicrobial activity and biofilm dissolution capacity. AgNp solution had less antimicrobial action in infected dentinal tubules compared with NaOCl (P < 0.05). The AgNp solution after 5 min was more effective in eliminating planktonic bacteria in dentinal tubules than in biofilm, but at 30 min fewer viable bacteria were observed in the biofilm compared with intratubular dentine (P < 0.05). AgNp irrigant was not as effective against E. faecalis compared to solutions commonly used in root canal

Preparation Prerequisites for Effective Irrigation of Apical Root Canal: A Critical Review.

PubMed

Tziafas, Dimitrios; Alraeesi, Dana; Al Hormoodi, Reem; Ataya, Maamoun; Fezai, Hessa; Aga, Nausheen

2017-10-01

It is well recognized that disinfection of the complex root canal system at the apical root canal remains the most critical therapeutic measure to treat apical periodontitis. Observational and experimental data in relation to the anatomy of the apical root canal in different tooth types and the cross sectional diameters of the apical part of the most commonly used hand and rotary files are critically reviewed. The present data analysis confirm that the challenging issue of antibacterial efficacy of modern preparation protocols in non-surgical endodontics requires more attention to apical root canal irrigation as a balance between safety and effectiveness. Ex vivo investigations clearly indicate that a specific design of the chemo-mechanical preparation is needed at the onset of RCT, more particularly in infected teeth. Design should be based on specific anatomical parameters, and must determine the appropriate size and taper of preparation as pre-requirements for effective and safe apical irrigation. The optimal irrigation protocols might be designed on the basis of technical specifications of the preparations procedures, such as the penetration depth, the type of the needle, the required time for continuous irrigant flow, the concentration of NaOCl, and the activation parameters. Key words: Endodontics, root canal treatment, instrumentation, irrigation, apical root canal.

Bilateral external ear canal osteomas - discussion on a clinical case.

PubMed

Gheorghe, D C; Stanciu, A E; Ulici, A; Zamfir-Chiru-Anton, A

2016-01-01

Osteomas of the external ear are uncommon benign tumors that need to be differentiated from the external ear canal exostoses, bony proliferations that are linked mainly to cold-water exposure. Clinical manifestations vary from no symptoms to recurrent local infections and external ear cholesteatoma. Objective: presenting a rare case that we did not find described in the published literature. A patient with multiple long-term asymptomatic osteomas of both external ear canals presented to our department. Material: Data recorded from the patient's medical record was reviewed and analyzed. Surgery was performed and histology confirmed the presumptive diagnosis. Results: There was a discrepancy between the local severity of the disease, with a complete obstruction of his ear canals, and the long-term disease-free status of the patient. Conclusion: We hypothesized about the etiology of these multiple bilateral osteomas of the EAC, in light of the clinical and surgical findings.

Efficacy of 3D conforming nickel titanium rotary instruments in eliminating canal wall bacteria from oval-shaped root canals.

PubMed

Bortoluzzi, Eduardo A; Carlon, Daniel; Meghil, Mohamed M; El-Awady, Ahmed R; Niu, Lina; Bergeron, Brian E; Susin, Lisiane; Cutler, Christopher W; Pashley, David H; Tay, Franklin R

2015-05-01

To evaluate the effectiveness of TRUShape® 3D Conforming Files, compared with Twisted Files, in reducing bacteria load from root canal walls, in the presence or absence of irrigant agitation. Extracted human premolars with single oval-shaped canals were infected with Enterococcus faecalis. Teeth in Group I (N=10; NaOCl and QMix® 2in1 as respective initial and final irrigants) were subdivided into 4 subgroups: (A) TRUShape® instrumentation without irrigant activation; (B) TRUShape® instrumentation with sonic irrigant agitation; (C) Twisted Files without irrigant agitation; (D) Twisted Files with sonic irrigant agitation. To remove confounding factor (antimicrobial irrigants), teeth in Group II (N=10) were irrigated with sterile saline, using the same subgroup designations. Specimens before and after chemomechanical débridement were cultured for quantification of colony-forming units (CFUs). Data from each group were analyzed separately using two-factor ANOVA and Holm-Sidak multiple comparison (α=0.05). Canal wall bacteria were qualitatively examined using scanning electron microscopy (SEM) and light microscopy of Taylor-modified Brown and Brenn-stained demineralised sections. CFUs from subgroups in Group I were not significantly different (P=0.935). For Group II, both file type (P<0.001) and irrigant agitation (P<0.001) significantly affected log-reduction in CFU concentrations. The interaction of these two factors was not significant (P=0.601). Although SEM showed reduced canal wall bacteria, bacteria were present within dentinal tubules after rotary instrumentation, as revealed by light microscopy of longitudinal root sections. TRUShape® files removed significantly more canal wall bacteria than Twisted Files when used without an antibacterial irrigant; the latter is required to decontaminate dentinal tubules. Root canal disinfection should not be focused only on a mechanistic approach. Rather, the rational choice of a rotary instrumentation system should be

7. O'BRIAN CANAL After its bifurcation with the DenverHudson Canal, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

7. O'BRIAN CANAL After its bifurcation with the Denver-Hudson Canal, flowing into Barr Lake through a protected eagle nesting area - O'Brian Canal, South Platte River Drainage Area Northest of Denver, Brighton, Adams County, CO

[Root canal treatment of mandibular first premolar with 4 root canals: a case report].

PubMed

Liu, Xin-yang; Zhan, Fu-Liang

2015-10-01

The mandibular first premolar can be considered one of the most challenging teeth to treat, due to the complexity of its root canal morphology and increased incidence of multiple canals. A case of endodontic treatment of a mandibular first premolar exhibiting a total of 4 distinct root canals and 4 apical foramina was described. Anatomic variation of root canal morphology should be considered in endodontic treatment to ensure a favorable healing outcome, and its identification could be enhanced by careful examination using a dental operating microscope. Obturation of root canals using a warm vertical compaction technique with a highly-radiopaque root canal sealer, such as AH Plus, after careful ultrasonic activated irrigation might allow the flow of sealer into the narrowed but unprepared part of the canal, thereby facilitating optimum chemo-mechanical debridement of the root canal system.

Bacteria in the apical root canals of teeth with apical periodontitis.

PubMed

Lee, Li-Wan; Lee, Ya-Ling; Hsiao, Sheng-Huang; Lin, Hung-Pin

2017-06-01

Bacteria in the tooth root canal may cause apical periodontitis. This study examined the bacterial species present in the apical root canal of teeth with apical periodontitis. Antibiotic sensitivity tests were performed to evaluate whether these identified bacterial species were susceptible to specific kinds of antibiotics. Selective media plating and biochemical tests were used first to detect the bacterial species in samples taken from the apical portion of root canals of 62 teeth with apical periodontitis. The isolated bacterial species were further confirmed by matrix-assisted laser desorption ionization-time of flight mass spectrometry. We found concomitant presence of two (32 teeth) or three species (18 teeth) of bacteria in 50 (80.6%) out of 62 tested teeth. However, only 34 bacterial species were identified. Of a total of 118 bacterial isolates (83 anaerobes and 35 aerobes), Prophyromonas endodontalis was detected in 10; Bacteroides, Dialister invisus or Fusobacterium nucleatum in 9; Treponema denticola or Enterococcus faecalis in 8; Peptostreptococcus or Olsenella uli in 6; and Veillonella in 5 teeth. The other 25 bacterial species were detected in fewer than five teeth. Approximately 80-95% of bacterial isolates of anaerobes were sensitive to ampicillin/sulbactam (Unasyn), amoxicillin/clavulanate (Augmentin), cefoxitin, and clindamycin. For E. faecalis, 85-90% of bacterial isolates were sensitive to gentamicin and linezolid. Root canal infections are usually caused by a mixture of two or three species of bacteria. Specific kinds of antibiotic can be selected to control these bacterial infections after antibiotic sensitivity testing. Copyright © 2016. Published by Elsevier B.V.

Comparison of Different Irrigants in the Removal of Endotoxins and Cultivable Microorganisms from Infected Root Canals

PubMed Central

Valera, Marcia Carneiro; Cardoso, Flávia Goulart da Rosa; Chung, Adriana; Xavier, Ana Cláudia Carvalho; Figueiredo, Mariana Diehl; Martinho, Frederico Canato; Palo, Renato Miotto

2015-01-01

This study was conducted to compare the effectiveness of different irrigants used to remove endotoxins and cultivable microorganisms during endodontic therapy. Forty root canals were contaminated and divided into groups according to the irrigant: 2% NaOCl + surfactant, 2% CHX, 2.5% NaOCl, and pyrogen-free saline solution (control). Samples were collected after root canal contamination (S1), after instrumentation (S2), and 7 days after instrumentation (S3). Microorganisms and endotoxins were recovered from 100% of the contaminated root canals (S1). At S2, 2% NaOCl + surfactant, 2% CHX, and 2.5% NaOCl were able to completely eliminate cultivable microorganisms. At S3, both 2% CHX and 2.5% NaOCl were effective in preventing C. albicans and E. coli regrowth, but E. faecalis was still detected. No microorganism species was recovered from root canals instrumented with 2% NaOCl + surfactant. At S2, a higher percentage value of endotoxin reduction was found for 2% NaOCl + surfactant (99.3%) compared to 2% CHX (98.9%) and 2.5% NaOCl (97.18%) (p < 0.05). Moreover, at S3, 2% NaOCl + surfactant (100%) was the most effective irrigant against endotoxins. All irrigants tested were effective in reducing microorganisms and endotoxins from root canals. Moreover, 2% NaOCl + surfactant was the most effective irrigant against endotoxins and regrowth of microorganisms. PMID:26346574

Evaluation of instrumentation systems in reducing E. faecalis from root canals: TF adaptive and ProTaper next versus single file systems.

PubMed

Karataş, Ertuğrul; Gültekin, Esra; Arslan, Hakan; Kirici, Damla Özsu; Alsancak, Meltem; Topçu, Meltem Çolak

2015-03-01

To compare the effect of the TF Adaptive, ProTaper Next, OneShape, WaveOne, Reciproc, (SAF) on the reduction of E. faecalis in experimentally infected root canals. 70 human mandibular incisor teeth with straight roots and single root canals were selected for this experiment and the root canals of the selected teeth were infected with E. faecalis. After contamination, all the root canals were randomly divided into 7 groups: control, ProTaper Next, TF Adaptive, SAF, WaveOne, Reciproc, and OneShape. After the irrigation procedures, samples were taken from root canals with paper points and incubated in blood agar plates. The colonies grown on the blood agar were counted and interpreted as colony forming units per milliliter. Analysis of results showed that all instrumentation systems were more effective in reducing the number of bacteria than the control (P<.001). The ProTaper Next, TF Adaptive, WaveOne, Reciproc, and OneShape systems were significantly more effective than the SAF system in reducing E. faecalis within the root canals (P<.001). All instrumentation systems used in this study provided a significant reduction in bacterial populations.

ASTER Suez Canal

NASA Image and Video Library

2000-10-06

One of the most important waterways in the world, the Suez Canal runs north to south across the Isthmus of Suez in northeastern Egypt. This image of the canal covers an area 36 kilometers (22 miles) wide and 60 kilometers (47 miles) long in three bands of the reflected visible and infrared wavelength region. It shows the northern part of the canal, with the Mediterranean Sea just visible in the upper right corner. The Suez Canal connects the Mediterranean Sea with the Gulf of Suez, an arm of the Red Sea. The artificial canal provides an important shortcut for ships operating between both European and American ports and ports located in southern Asia, eastern Africa, and Oceania. With a length of about 195 kilometers (121 miles) and a minimum channel width of 60 meters (197 feet), the Suez Canal is able to accommodate ships as large as 150,000 tons fully loaded. Because no locks interrupt traffic on this sea level waterway, the transit time only averages about 15 hours. ASTER acquired this scene on May 19, 2000. http://photojournal.jpl.nasa.gov/catalog/PIA02661

Prevalence and clonal analysis of Porphyromonas gingivalis in primary endodontic infections.

PubMed

Siqueira, José F; Rôças, Isabela N; Silva, Marlei G

2008-11-01

This study investigated the prevalence of Porphyromonas gingivalis in 62 teeth with primary endodontic infections by using a species-specific 16S rRNA gene-based nested polymerase chain reaction assay. P. gingivalis isolates recovered from 2 infected root canals were also analyzed for clonal diversity by using arbitrarily primed PCR. Overall, P. gingivalis was found in 48% of the samples. This species was specifically detected in 36% of canals of teeth with chronic apical periodontitis, in 46% of the cases of acute apical periodontitis, and in 67% of acute apical abscesses. P. gingivalis was significantly more frequent in abscess aspirates than in canals of teeth with chronic apical periodontitis (P < .05). Typing of colonies retrieved from 2 infected canals revealed 2 clones per individual. These findings confirmed that P. gingivalis can be an important endodontic pathogen, mostly associated with acute abscesses, and demonstrated that different clonal types of this species can colonize the root canal in the same individual.

[Scanning electron microscopy investigation of canal cleaning after canal preparation with nickel titanium files].

PubMed

Brkanić, Tatjana; Ivana, Stojsin; Vukoje, Karolina; Zivković, Slavoljub

2010-01-01

Root canal preparation is the most important phase of endodontic procedure and it consists of adequate canal space cleaning and shaping. In recent years, rotary instruments and techniques have gained importance because of the great efficacy, speed and safety of the preparation procedure. The aim of this research was to investigate the influence of different NiTi files on the canal wall cleaning quality, residual dentine debris and smear layer. The research was conducted on extracted human teeth in vitro conditions. Teeth were divided in 7 main groups depending on the kind of instruments used for root canal preparation: ProTaper, GT, ProFile, K-3, FlexMaster, hand ProTaper and hand GT. Root canal preparation was accomplished by crown-down technique. Prepared samples were assessed on scanning electron microscopy JEOL, JSM-6460 LV. The evaluation of dentine debris was done with 500x magnification, and the evaluation of smear layer with 1,000 times magnification. Quantitive assessment of dentine debris and smear layer was done according to the criteria of Hulsmann. The least amount of debris and smear layer has been found in canals shaped with ProFile instruments, and the largest amount in canals shaped with FlexMaster instruments. Canal cleaning efficacy of hand GTand ProTaperfiles has been similar to cleaning efficacy of rotary NiTi files. Statistic analysis has shown a significant difference in amount of dentine debris and smear layer on the canal walls between sample groups. shaped with different instruments. Completely clean canals have not been found in any tested group of instruments. The largest amount of debris and smear layer has been found in the apical third of all canals. The design and the type of endodontic instruments influence the efficacy of the canal cleaning.

Diversity of human papillomavirus in the anal canal of men: the HIM Study.

PubMed

Sichero, L; Nyitray, A G; Nunes, E M; Nepal, B; Ferreira, S; Sobrinho, J S; Baggio, M L; Galan, L; Silva, R C; Lazcano-Ponce, E; Giuliano, A R; Villa, L L

2015-05-01

Human papillomavirus (HPV) infections are associated with the development of anogenital lesions in men. There are no reports describing the distribution of non-α HPV types in the anal canal of a sexually diverse group of men. The HPV Infection in Men (HIM) Study is a multicentre study on the natural history of HPV infection in Brazil, Mexico, and the USA. At baseline, 12% of anal canal PCR HPV-positive specimens were not typed by the Roche Linear Array, and were considered to be unclassified. Our goals were to characterize HPVs among these unclassified specimens at baseline, and to assess associations with participant socio-demographic and behavioural characteristics. Unclassified HPVs were typed by sequencing of amplified PGMY09/11 products or cloning of PGMY/GP + nested amplicons followed by sequencing. Further analysis was conducted with FAP primers. Of men with unclassified HPV in the anal canal, most (89.1%) were men who have sex with women. Readable sequences were produced for 62.8% of unclassified specimens, of which 75.2% were characterized HPV types. Eighteen, 26 and three different α-HPV, β-HPV and γ-HPV types were detected, respectively. α-HPVs were more commonly detected among young men (18-30 years) than among older men (45-70 years), whereas β-HPVs were more frequent among mid-adult men (31-44 years). β-HPVs were more common among heterosexual men (85.0%) than among non-heterosexual men. All β-HPVs detected among non-heterosexual men were β2-HPV types. The high prevalence of β-HPV in the anal canal of men who do not report receptive anal sex is suggestive of other forms of transmission that do not involve penile-anal intercourse. Copyright © 2015 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Molecular identification and quantification of bacteria from endodontic infections using real-time polymerase chain reaction.

PubMed

Blome, B; Braun, A; Sobarzo, V; Jepsen, S

2008-10-01

It was the aim of the present study to evaluate root canal samples for the presence and numbers of specific species as well as for total bacterial load in teeth with chronic apical periodontitis using quantitative real-time polymerase chain reaction (PCR). Forty adult patients with one radiographically documented periapical lesion were included. Twenty teeth presented with primary infections and 20 with secondary infections, requiring retreatment. After removal of necrotic pulp tissue or root canal filling, a first bacterial sample was obtained. Following chemo-mechanical root canal preparation a second sample was taken and a third sample was obtained after 14 days of intracanal dressing with calcium hydroxide. Analysis by real-time PCR enabled the quantification of total bacterial counts and of nine selected species. Root canals with primary infections harbored significantly more bacteria (by total bacterial count) than teeth with secondary infections (P < 0.05). Mean total bacterial count in the retreatment group was 2.1 x 10(6) and was significantly reduced following root canal preparation (3.6 x 10(4)) and intracanal dressing (1.4 x 10(5)). Corresponding values for primary infections were: 4.6 x 10(7), 3.6 x 10(4), and 6.9 x 10(4). The numbers of the selected bacteria and their detection frequency were also significantly reduced. Root canals with primary infections contained a higher bacterial load. Chemo-mechanical root canal preparation reduced bacterial counts by at least 95%.

Clonality of bacterial consortia in root canals and subjacent gingival crevices.

PubMed

Parahitiyawa, Nipuna B; Chu, Frederick C S; Leung, Wai K; Yam, Wing C; Jin, Li Jian; Samaranayake, Lakshman P

2015-02-01

No oral niche can be considered to be segregated from the subjacent milieu because of the complex community behavior and nature of the oral biofilms. The aim of this study was to address the paucity of information on how these species are clonally related to the subjacent gingival crevice bacteria. We utilized a metagenomic approach of amplifying 16S rDNA from genomic DNA, cloning, sequencing and analysis using LIBSHUFF software to assess the genetic homogeneity of the bacterial species from two infected root canals and subjacent gingival crevices. The four niches studied yielded 186 clones representing 54 phylotypes. Clone library comparisons using LIBSHUFF software indicated that each niche was inhabited by a unique flora. Further, 42% of the clones were of hitherto unknown phylotypes indicating the extent of bacterial diversity, especially in infected root canals and subjacent gingival crevices. We believe data generated through this novel analytical tool shed new light on understanding oral microbial ecosystems. © 2014 Wiley Publishing Asia Pty Ltd.

Effect of automatic cluster removers on milking efficiency and teat condition of Manchega ewes.

PubMed

Bueso-Ródenas, J; Romero, G; Arias, R; Rodríguez, A M; Díaz, J R

2015-06-01

Milking operations represent more than 50% of the work on a dairy ewe farm. The implementation of automatic cluster removers (ACR) is gaining popularity, as it allows the operator to avoid manual cluster detachments, simplifying the milking routines. The aim of this study was to discover the effect on the milking of Manchega ewes over an entire lactation period by using this type of devices, set up with 2 different combinations of milk flow threshold (MF) and delay time (DT) and comparing them with the traditional method using manual cluster removal. During a 15-d pre-experimental period, the animals were milked without ACR and sampling was performed to select 108 ewes and distribute them into 3 groups of similar characteristics according to their parity, milk yield, milking duration, and mammary gland sanitary status. Later, each group was milked for a duration of 4 mo in 3 different conditions: 1 with manual cluster removal, the second setting the ACR at MF 150 g/min and DT 20 s, and the third setting the ACR at MF 200 g/min and DT 10 s. Samplings of milking fraction, milking duration, milk composition, mammary gland sanitary status, teat-end status, and vacuum level in the short milk tubes during milking were performed. The use of ACR limited the vacuum drops in the short milk tubes and the edema in the teat end after milking, although no reduction in the number of new cases of mastitis was observed and the milk composition did not change. Moreover, it was noted that the use of ACR set with MF 150 g/min and DT 20 s was more efficient than the manual cluster removal, as it obtained a similar amount of extracted milk but took less time. Conversely, the use of ACR set with MF 200 g/min and DT 10 s involved a higher reduction in individual milking duration and the milking duration of groups of animals but reduced milk extracted. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

An observational cohort study on persistency of internal teat sealant residues in milk after calving in dairy cows.

PubMed

Kabera, Fidèle; Dufour, Simon; Keefe, Greg; Roy, Jean-Philippe

2018-04-04

Our objectives were to evaluate the prevalence of quarters with an observable internal teat sealant (ITS) plug at first milking following calving and investigate persistency of ITS residues in milk after calving. An observational cohort study was carried out on 557 quarters of 156 cows treated with ITS in 6 farms in Quebec, Canada. The presence of an ITS plug at first milking and ITS residues in milk at each milking were observed by producers. The effects of various factors on the odds of observing an ITS plug and persistency of ITS residues in milk were studied using generalized logistic mixed and generalized negative binomial mixed models, respectively. Milk samples were taken on the day before dry-off and on 2 occasions after calving for bacterial identification to detect intramammary infection (IMI) using bacteriological culture followed by MALDI-TOF identification. The association between the absence of an ITS plug and the presence of new IMI was assessed using a mixed logistic regression model. Internal teat sealant plugs after calving were more often observed in rear quarters and in quarters receiving ITS alone at drying-off versus antimicrobial and ITS. We observed an average (standard deviation) persistency of 4.0 d (2.3 d). When an ITS plug was still present at first milking (83% of quarters), the elimination of ITS residues in milk after calving was significantly longer (4.5 d, on average) compared with 1.2 d when an ITS plug was absent. In cows with an ITS plug at calving, we observed a higher number of days of excretion in older cows. When a plug could not be observed, rear quarters, older cows, and cows with a long dry period duration excreted ITS residues for a significantly longer period. The lack of a significant association between the absence of a plug and the odds of new IMI at calving suggests that despite the loss of the plug, cows were still protected against new IMI. Although we were able to highlight some statistically significant risk

2. VIEW SOUTH, GENERAL VIEW SHOWING CANAL, CANAL SPILLWAY ON ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

2. VIEW SOUTH, GENERAL VIEW SHOWING CANAL, CANAL SPILLWAY ON LEFT, DRAIN GATE GATEHOUSE IN DISTANCE - Norwich Water Power Company, West bank of Shetucket River beginning opposite Second Street & extending .8 mile northward, Greenville section, Norwich, New London County, CT

Photodynamic therapy with water-soluble phtalocyanines against bacterial biofilms in teeth root canals

NASA Astrophysics Data System (ADS)

Gergova, Raina; Georgieva, Tzvetelina; Angelov, Ivan; Mantareva, Vanya; Valkanov, Serjoga; Mitov, Ivan; Dimitrov, Slavcho

2012-06-01

The study presents the PDT with metal phthalocyanines on biofilms grown in root canals of ten representatives of the Gram-positive and the Gram-negative bacterial species and a fungus Candida albicans which cause aqute teeth infections in root canals.. The extracted human single-root teeth infected for 48 h with microorganisms in conditions to form biofilms of the above pathogens were PDT treated. The stage of biofilm formation and PDT effect of the samples of the teeth were determined by the scaning electron microscopy and with standard microbial tests. The PDT treating procedure included 10 min incubation with the respected phthalocyanine and irradiated with 660 nm Diode laser for 10 min. The most strongly antibacterial activity was achieved with zinc(II) phthalocyanine (ZnPc) against Enterococcus faecalis, Staphylococcus aureus and Moraxella catarrhalis. The other Gram-negative bacteria and Candida albicans were 10-100 times more resistant than the Gram-positive species. The Gram-negative Moraxella catarrhalis and Acinetobacter baumannii were more sensitive than the enterobacteria, but eradication of Pseudomonas aeruginosa in biofilm was insignificant. The influence of the stage of biofilm formation and the initial conditions (bacterial density, photosensitizer concentration and energy fluence of radiation) to the obtained level of inactivation of biofilms was investigated. The PDT with ZnPc photosensitizers show a powerful antimicrobial activity against the most frequent pathogens in endodontic infections and this method for inactivation of pathogens may be used with sucsses for treatment of the bacterial biofilms in the root canals.

Endodontic management of mesiobuccal-2 canal in four-rooted and five-canalled mandibular third molar.

PubMed

Garg, Amit Kumar; Bhardwaj, Anuj; Mantri, Vijay R; Agrawal, Neha

2014-05-01

A case of unusual Root morphology is presented to demonstrate anatomic variations in mandibular third molar. The most common configuration of mandibular third molar is two Roots and three canals; however they may have many different combinations. Endodontic treatment was performed in mandibular third molar having aberrant anatomy. Four Root canal orifices were located with the aid of dental operating microscope (DOM) and three separate Roots were diagnosed with radiographs. Spiral computed tomography (SCT) showed the presence of an extra canal and extra Root, indicating a rare anatomic configuration. Looking for additional canals and Roots are important part of successful endodontics, as the knowledge of their existence enable clinicians to treat a case successfully that otherwise might end in failure. The use of DOM and SCT in this case greatly contributed toward making a confirmatory diagnosis and successful endodontic treatment of four-rooted and five-canalled mandibular third molar. Variation in Root canal anatomy is very common. Knowledge of these variations is very essential for successful Root canal outcome, inability to do so can lead to missed canals and failures. Hence, thorough knowledge of Root canal anatomy and advances in diagnostic aids are essential.

Antibacterial Efficacy of Super-Oxidized Water on Enterococcus faecalis Biofilms in Root Canal

PubMed Central

Zan, Recai; Alacam, Tayfun; Hubbezoglu, Ihsan; Tunc, Tutku; Sumer, Zeynep; Alici, Oguzhan

2016-01-01

Background The success of endodontic treatment depends on a few crucial factors. One of these factors is the complete chemomechanic preparation of root canal against various bacteria. In particular, the effect of resistant bacteria may cause intense pain with flare-up and formation of periapical lesions. Therefore, the strong effect of irrigants plays an important role in terms of the complete elimination of these bacteria to achieve long-term successful treatment. Objectives The aim of this study was to investigate the antibacterial effects of super-oxidized water (SPO) in root canals infected with Enterococcus faecalis biofilms. Methods One hundred twenty single-root, premolar teeth were selected. Initially, the teeth were prepared and then disinfected. E. faecalis were inoculated and kept at 37°C for 24 hours in the root canals. The re-inoculation procedure was repeated on the first, fourth, seventh, and tenth days. The infected root canals were divided into one negative (saline) and one positive (sodium hypochlorite) control group and four experimental groups (super-oxidized water: 1, 2, 3, or 5 minutes) (n = 20). Paper points were placed in the root canals to control and evaluate the biofilm formation. Biofilms were counted on blood agar plates, and data was evaluated and statistically analyzed using one-way ANOVA and Tukey’s test. Results Although sodium hypochlorite (NaOCl) showed no statistically significant difference when compared with three and five minutes of SPO irrigation (P > 0.05), NaOCl showed statistically significant differences among all other groups (P < 0.05). Conclusions Super-oxidized water indicated a remarkable and similar bactericidal effect to that of traditional NaOCl against E. faecalis biofilms. In terms of successful endodontic treatment approaches, super-oxidized water may be used as an effective irrigation solution in clinics. PMID:27800142

Endoscopic root canal treatment.

PubMed

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.

Atrioventricular Canal Defect

MedlinePlus

... birth (congenital). The condition is often associated with Down syndrome. Atrioventricular canal defect allows extra blood to flow ... baby's heart is developing. Some factors, such as Down syndrome, might increase the risk of atrioventricular canal defect. ...

[Pain, flare-ups and failures in root canal therapy].

PubMed

Moorer, W R

1989-10-01

In this overview the incidences and causes of pain, flare-ups and failures that occur after root canal therapy are discussed. Infection is considered the most important single, underlying determinant of the many factors that may cause pain and failures. Therefore, strict adherence to recognized therapeutic principles of shaping, disinfection and filling, in addition to proper aftercare, is of importance to diminish postoperative sequelae.

Thermal effects and antibacterial properties of energy levels required to sterilize stained root canals with an Nd:YAG laser.

PubMed

Ramsköld, L O; Fong, C D; Strömberg, T

1997-02-01

Thermal effects and antibacterial properties of an Nd:YAG laser were studied to establish clinically safe levels of energy to deliver into the root canal and to determine the energy level needed to sterilize infected root canals. The results indicate that lasing cycles of 3 J-s for 15 s followed by a 15-s recovery interval can be continued for prolonged periods without risk of thermal damage to surrounding tissues. In vitro lasing of root canals inoculated with dark stained bacteria showed that two such lasing cycles sterilized only two out of eight canals, whereas when four cycles were used seven out of eight canals were sterilized. Guidelines for energy levels in endodontic Nd:YAG laser work are discussed, and base data for calculating appropriate energy levels are given.

Types of trematodes infecting freshwater snails found in irrigation canals in the East Nile locality, Khartoum, Sudan.

PubMed

Mohammed, Nidal A I; Madsen, Henry; Ahmed, Abdel Aziz A R M

2016-02-25

The planorbid freshwater snails of the two genera, Biomphalaria and Bulinus -have been vigorously studied due to the role they play as intermediate hosts of schistosomiasis. In Sudan specifically, most studies have focused on the chemical and ecological control of the two genera, but few studies have looked at their biological control. This study explored the coexistence of other species of freshwater snails and the two genera along with their trematode infections in relation to a number of environmental factors in the East Nile locality, Khartoum state, Sudan. Freshwater snails from irrigation canals (abueshreens) were sampled monthly from January 2004 to December 2005. The snails were examined for trematode infections by cercarial emergence immediately after collection and then weekly for an additional four weeks to allow for the maturation of prepatent infections. Vegetation cover in the study sites as well as the physicochemical characteristics of the water, including temperature, were also recorded. A total of 10,493 snails, representing seven species, were collected. The most abundant species was Biomphalaria pfeifferi, representing 48.6 % of the sample. Overall, 14.1 % of the snails were found to be shedding some type of cercariae. Five species were found to have infections; among these the Bulinus truncatus species was found to be the most heavily infected, with an overall prevalence of 46.2 %. Double infections were recorded in only two B. truncatus snails and one Cleopatra bulimoides snail. Twenty different morphotypes of cercariae were recorded, seven of which appeared not to conform to previously described cercariae from Africa. Xiphidiocercariae type 1 was the most common type of cercariae recovered, accounting for 44.3 % of all infections. The density of snails tended to be lower during the summer months than the winter months, except for M. tuberculata snails, which were not affected by seasonal changes. The findings of this study indicate that

Challenges in fitting a hearing aid to a severely collapsed ear canal and mixed hearing loss.

PubMed

Oeding, Kristi; Valente, Michael; Chole, Richard

2012-04-01

Collapsed ear canals typically occur when an outside force, such as a headset for audiometric testing, is present. However, when a collapsed ear canal occurs without external pressure, this creates a challenge not only for performing audiometric testing but also for coupling a hearing aid to the ear canal. This case report highlights the challenges associated with fitting a hearing aid on a patient with a severe anterior-posterior collapsed ear canal with a mixed hearing loss. A 67-yr-old female originally presented to Washington University in St. Louis School of Medicine in 1996 with a long-standing history of bilateral otosclerosis. She had chronic ear infections in the right ear and a severely collapsed ear canal in the left ear and was fit with a bone anchored hearing aid (BAHA®) on the right side in 2003. However, benefit from the BAHA started to decrease due to changes in hearing, and a different hearing solution was needed. It was proposed that a hearing aid be fit to her collapsed left ear canal; however, trying to couple a hearing aid to the collapsed ear canal required unique noncustom earmold solutions. This case study highlights some of the obstacles and potential solutions for coupling a hearing aid to a severely collapsed ear canal. American Academy of Audiology.

Decreased levels of matrix metalloproteinase-2 in root-canal exudates during root canal treatment.

PubMed

Pattamapun, Kassara; Handagoon, Sira; Sastraruji, Thanapat; Gutmann, James L; Pavasant, Prasit; Krisanaprakornkit, Suttichai

2017-10-01

To determine the matrix metalloproteinase-2 (MMP-2) levels in root-canal exudates from teeth undergoing root-canal treatment. The root-canal exudates from six teeth with normal pulp and periradicular tissues that required intentional root canal treatment for prosthodontic reasons and from twelve teeth with pulp necrosis and asymptomatic apical periodontitis (AAP) were sampled with paper points for bacterial culture and aspirated for the detection of proMMP-2 and active MMP-2 by gelatin zymography and the quantification of MMP-2 levels by ELISA. By gelatin zymography, both proMMP-2 and active MMP-2 were detected in the first collection of root-canal exudates from teeth with pulp necrosis and AAP, but not from teeth with normal pulp, and their levels gradually decreased and disappeared at the last collection. Consistently, ELISA demonstrated a significant decrease in MMP-2 levels in the root-canal exudates of teeth with pulp necrosis and AAP following root canal procedures (p<0.05). Furthermore, the MMP-2 levels were significantly lower in the negative bacterial culture than those in the positive bacterial culture (p<0.001). The levels of MMP-2 in root-canal exudates from teeth with pulp necrosis and AAP were gradually reduced during root canal procedures. Future studies are required to determine if MMP-2 levels may be used as a biomolecule for the healing of apical lesions, similar to the clinical application of MMP-8 as a biomarker. Copyright © 2017 Elsevier Ltd. All rights reserved.

Experimental infection of bovine mammary gland with prototheca zopfii genotype 1.

PubMed

Ito, Takaaki; Kano, Rui; Sobukawa, Hideto; Ogawa, Jin; Honda, Yayoi; Hosoi, Yoshihiro; Shibuya, Hisashi; Sato, Tsuneo; Hasegawa, Atsuhiko; Kamata, Hiroshi

2011-01-01

Prototheca zopfii is divided into three genotypes, one of which, P. zopfii genotype 2, appears to be the main causative agent of bovine protothecal mastitis. However, the difference in pathogenicity between genotypes 1 and 2 has not been well investigated. In the present study, we experimentally infected normal bovine mammary gland with P. zopfii genotype 1 to investigate its pathogenicity. The mammary gland infected with P. zopfii genotype 1 showed no clinical signs. However, the histopathologic features of the infected mammary gland consisted of interstitial infiltrates of macrophages, plasma cells, lymphocytes, and fibroblasts with neutrophils in acinar lumens. Algae were present in macrophages and free in the alveolar lumens and the interstitium. Histopathology of the resultant tissue samples revealed that genotype 1 also induced a granulomatous lesion in the cow teat, similar to the mastitis lesion due to genotype 2.

[Infections as a preoperative problem in patients with tetralogy of Fallot (TOF) associated with complete atrioventricular canal septal defect (AVC)].

PubMed

Szydłowski, Lesław; Marek-Szydłowska, Teresa; Rudziński, Andrzej; Pajak, Jacek; Morka, Jacek; Stołtny, Ludwik

2004-01-01

Tetralogy of Fallot (TOF) coexisting with atrioventricular canal septal defect (AVC) is a rare combination of anomalies. Additionally, in cases with concomitant Down syndrome, recurrent infections can be a serious problem in patients (pts.) waiting for cardiosurgery treatment. The purpose of the study was an analysis of types of infections and other factors complicating the preoperative period in those patients. The study group consisted of 17 pts. with TOF and AVC aged from 1 day to 9 years (mean 9.4 month). In this group there were 11 pts. with Down syndrome. All of them were subjected to physical examinations, blood analysis, ECG, chest X-ray and echocardiographic study. Additionally, in 8 pts. we performed catheterization. The signs of different types of infection were analyzed and results were compared in two groups: with and without Down syndrome. The differences were observed in the frequency of recurrent or chronic infections (21 v/s 4), time of hospitalization before surgery (17 v/s 9 days), necessity (11 v/s 3) and duration of antibiotic therapy (19 v/s 7 days) in the two studied groups. Elevated body temperature of unknown etiology was noted in 8 cases with Down syndrome, compared to 1 patient without trisomy 21. Also, the children with Down syndrome had to wait 11 days longer (19 v/s 8) for discharge after operation. Infections in children with TOF, AVC and Down syndrome significantly complicate the natural course of this anomaly. Prolonged preoperation time is characteristic of Down syndrome pts. compared to patients without chromosomal abnormalities.

Comparing irradiation parameters on disinfecting enterrecoccus faecalis in root canal disinfection

NASA Astrophysics Data System (ADS)

Sarp, Ayşe. S.; Gülsoy, Murat

2016-02-01

Although conventional method carries all the debris, studies on persisting infections in root canals show bacteria and their toxins spread from the root canal and contaminate the apical region. Thus developes apical periodontitis or symptoms, and loss of tooth. Even if the treatment has adequate success, anatomy of root canal system can be very complexwith accessory canals. The disinfecting effect of laser radiation has only recently been used in dentistry. Laser irradiation has a bactericidal effect. Each wavelength has its own advantages and limitations according to their different absorption characteristics, depending on their 'absorption coefficient'. The sterilizing efficiency of two types of wavelengths, a new fiber laser 1940- nm Thulium fiber Laser and an 2940 nm Er:YAG Laser were compared in this study. Irradiation with a power of 0.50 W with 1940- nm Thulium fiber Laser disinfected 95,15% of bacteria, however irradiation with same laser power with Er:YAG Laser caused a reduction of 96,48 %. But there was no significant difference in the disinfection effect of two different laser groups ( p < 0.05, Mann- U-Whitney Test). In addition to this, Er :YAG Laser caused three times more reduction from its own positive control group where 1940- nm Thulium fiber Laser caused 2,5 times effective disinfection.

Antibacterial effects of Nd:YAG laser irradiation within root canal dentin.

PubMed

Klinke, T; Klimm, W; Gutknecht, N

1997-02-01

The microbial flora of the root canal dentin can cause failures in the conventional treatment of infected root canals if it cannot be sufficiently removed by preparation and chemical disinfection of the root canal. The aim of this study is to examine the bactericidal effects of neodymium:yttriumaluminum garnet (Nd:YAG) laser irradiation in the depth of the root canal dentin. Following sterilization, longitudinal section dentin slices of different thicknesses (100-1000 microns) were inoculated on one side with 4 microliters of a Streptococcus mutans suspension. The opposite sides of the dentin slices were then irradiated four times for 10-20 sec (according to the sample area) using the Nd:YAG laser at a setting of 1.5 W, 15 pps with a 200 microns glass fiber from an angle of about 5 degrees. The bacteria were then removed from the dentin using vibration and plated out on culture dishes that were selective for Streptococcus mutans. When compared with untreated control slices, counting of the colonies revealed a highly significant elimination of bacteria for all thicknesses following laser irradiation. Although the intensity of the laser irradiation decreased after penetration of a 1000-micron dentin slice, the bactericidal mode of action was still effective.

Unusual Root Canal Irrigation Solutions.

PubMed

Mohammadi, Zahed; Jafarzadeh, Hamid; Shalavi, Sousan; Kinoshita, Jun-Ichiro

2017-05-01

Microorganisms and their by-products play a critical role in pulp and periradicular pathosis. Therefore, one of the main purposes of root canal treatment is disinfection of the entire system of the canal. This aim may be obtained using mechanical preparation, chemical irrigation, and temporary medication of the canal. For this purpose, various irrigation solutions have been advocated. Common root canal irrigants, such as sodium hypochlorite, chlorhexidine, and a mixture of tetracycline, acid, and detergent have been extensively reviewed. The aim of this review was to address the less common newer root canal irrigation solutions, such as citric acid, maleic acid, electrochemically activated water, green tea, ozonated water, and SmearClear.

Porphyromonas (Bacteroides) endodontalis: its role in endodontal infections.

PubMed

van Winkelhoff, A J; van Steenbergen, T J; de Graaff, J

1992-09-01

Porphyromonas endodontalis (formerly Bacteroides endodontalis) is a black-pigmented anaerobic Gram-negative rod which is associated with endodontal infections. It has been isolated from infected dental root canals and submucous abscesses of endodontal origin. The presence of P. endodontalis in infected dental root canals has been correlated with symptoms of an acute infection. It is occasionally found on oral mucous membranes and periodontal pockets. P. endodontalis has shown relatively low virulence in experimental monoinfections. In anaerobic mixed infections it can play an essential role. Differences in virulence between strains have been related to capsular material. On the basis of different types of capsules, three serotypes have been described. P. endodontalis is sensitive to a wide range of antibiotics, including the penicillins, the tetracyclines, and metronidazole.

Osmolarity and root canal antiseptics.

PubMed

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

Additional disinfection with a modified salt solution in a root canal model.

PubMed

van der Waal, Suzette V; Oonk, Charlotte A M; Nieman, Selma H; Wesselink, Paul R; de Soet, Johannes J; Crielaard, Wim

2015-10-01

The aim of this study is to investigate the disinfecting properties of a modified salt solution (MSS) and calcium hydroxide (Ca(OH)2) in a non-direct-contact ex-vivo model. Seventy-four single-canal roots infected with Enterococcus faecalis were treated with 1% sodium hypochlorite (NaOCl) irrigation or with NaOCl irrigation with subsequent dressing with MSS or Ca(OH)2. After removal of the dressings, the roots were filled with bacterial growth medium and incubated for seven days to enable the surviving bacteria to repopulate the root canal lumen. Growth was determined by sampling the root canals with paper points before treatment (S1), after treatment (S2) and incubation after treatment (S3). The colony forming units were counted at S1 and S2. At S3, growth was determined as no/yes regrowth. The Kruskal-Wallis, McNemar and χ(2) test were used for statistical analyses. At S2, in the NaOCl group, growth was found in 5 of 19 root canals. After the removal of MSS or Ca(OH)2 bacteria were retrieved from one root canal in both groups. At S3, repopulation of the root canals had occurred in 14 of 19 roots after sole NaOCl irrigation, 6 of 20 roots after MSS-dressing and in 14 of 20 roots after Ca(OH)2-dressing. MSS was more effective in preventing regrowth than Ca(OH)2 (P=0.009). The modified salt solution prevented regrowth in roots which indicates that it can eliminate persistent bacteria. Dressing the root canals with Ca(OH)2 did not provide additional disinfection after NaOCl irrigation. Copyright © 2015 Elsevier Ltd. All rights reserved.

Response to alkaline stress by root canal bacteria in biofilms.

PubMed

Chávez de Paz, L E; Bergenholtz, G; Dahlén, G; Svensäter, G

2007-05-01

To determine whether bacteria isolated from infected root canals survive alkaline shifts better in biofilms than in planktonic cultures. Clinical isolates of Enterococcus faecalis, Lactobacillus paracasei, Olsenella uli, Streptococcus anginosus, S. gordonii, S. oralis and Fusobacterium nucleatum in biofilm and planktonic cultures were stressed at pH 10.5 for 4 h, and cell viability determined using the fluorescent staining LIVE/DEAD BacLight bacterial viability kit. In addition, proteins released into extracellular culture fluids were identified by Western blotting. Enterococcus faecalis, L. paracasei, O. uli and S. gordonii survived in high numbers in both planktonic cultures and in biofilms after alkaline challenge. S. anginosus, S. oralis and F. nucleatum showed increased viability in biofilms compared with planktonic cultures. Alkaline exposure caused all planktonic cultures to aggregate into clusters and resulted in a greater extrusion of cellular proteins compared with cells in biofilms. Increased levels of DnaK, HPr and fructose-1,6-bisphosphate aldolase were observed in culture fluids, especially amongst streptococci. In general, bacteria isolated from infected roots canals resisted alkaline stress better in biofilms than in planktonic cultures, however, planktonic cells appeared to use aggregation and the extracellular transport of specific proteins as survival mechanisms.

Effects on milk yield of milking interval regularity and teat cup attachment failures with robotic milking systems.

PubMed

Bach, Alex; Busto, Isabel

2005-02-01

A database consisting of 35291 milking records from 83 cows was built over a period of 10 months with the objectives of studying the effect of teat cup attachment failures and milking interval regularity on milk production with an automated milking system (AMS). The database collected records of lactation number, days in milk (DIM), milk production, interval between milkings (for both the entire udder and individual quarters in case of a teat cup attachment failure) and average and peak milk flows for each milking. The weekly coefficient of variation (CV) of milking intervals was used as a measure of milking regularity. DIM, milking intervals, and CV of milking intervals were divided into four categories coinciding with the four quartiles of their respective distributions. The data were analysed by analysis of variance with cow as a random effect and lactation number, DIM, the occurrence of a milking failure, and the intervals between milkings or the weekly CV of milking intervals as fixed effects. The incidence of attachment failures was 7.6% of total milkings. Milk production by quarters affected by a milking failure following the failure was numerically greater owing to the longer interval between milkings. When accounting for the effect of milking intervals, milk production by affected quarters following a milking failure was 26% lower than with regular milkings. However, the decrease in milk production by quarters affected by milking failures was more severe as DIM increased. Average and peak milk flows by quarters affected by a milking failure were lower than when milkings occurred normally. However, milk production recovered its former level within seven milkings following a milking failure. Uneven frequency (weekly CV of milking intervals >27%) decreased daily milk yield, and affected multiparous more negatively than primiparous cows.

Comparison of canal transportation in simulated curved canals prepared with ProTaper Universal and ProTaper Gold systems

PubMed Central

Muniz, Brenda Leite; Pires, Frederico; Belladonna, Felipe Gonçalves; Neves, Aline Almeida; Souza, Erick Miranda; De-Deus, Gustavo

2016-01-01

Objectives The purpose of this study was to assess the ability of ProTaper Gold (PTG, Dentsply Maillefer) in maintaining the original profile of root canal anatomy. For that, ProTaper Universal (PTU, Dentsply Maillefer) was used as reference techniques for comparison. Materials and Methods Twenty simulated curved canals manufactured in clear resin blocks were randomly assigned to 2 groups (n = 10) according to the system used for canal instrumentation: PTU and PTG groups, upto F2 files (25/0.08). Color stereomicroscopic images from each block were taken exactly at the same position before and after instrumentation. All image processing and data analysis were performed with an open source program (FIJI). Evaluation of canal transportation was obtained for two independent canal regions: straight and curved levels. Student's t test was used with a cut-off for significance set at α = 5%. Results Instrumentation systems significantly influenced canal transportation (p < 0.0001). A significant interaction between instrumentation system and root canal level (p < 0.0001) was found. PTU and PTG systems produced similar canal transportation at the straight part, while PTG system resulted in lower canal transportation than PTU system at the curved part. Canal transportation was higher at the curved canal portion (p < 0.0001). Conclusions PTG system produced overall less canal transportation in the curved portion when compared to PTU system. PMID:26877984

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

PubMed

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.

Limitations of navigation through Nubaria canal, Egypt.

PubMed

Samuel, Magdy G

2014-03-01

Alexandria port is the main Egyptian port at the Mediterranean Sea. It is connected to the Nile River through Nubaria canal, which is a main irrigation canal. The canal was designed to irrigate eight hundred thousand acres of agricultural lands, along its course which extends 100 km. The canal has three barrages and four locks to control the flow and allow light navigation by some small barges. Recently, it was decided to improve the locks located on the canal. More than 40 million US$ was invested in these projects. This decision was taken to allow larger barges and increase the transported capacity through the canal. On the other hand, navigation through canals and restricted shallow waterways is affected by several parameters related to both the channel and the vessel. Navigation lane width as well as vessel speed and maneuverability are affected by both the channel and vessel dimensions. Moreover, vessel dimensions and speed will affect the canal stability. In Egypt, there are no guide rules for navigation through narrow and shallow canals such Nubaria. This situation threatens the canal stability and safety of navigation through it. This paper discussed the characteristics of Nubaria canal and the guide rules for navigation in shallow restricted water ways. Dimensions limitation for barges navigating through Nubaria canal is presented. New safe operation rules for navigation in Nubaria canal are also presented. Moreover, the implication of navigation through locks on canal discharge is estimated.

[Continuous observation of canal aberrations in S-shaped simulated root canal prepared by hand-used ProTaper files].

PubMed

Xia, Ling-yun; Leng, Wei-dong; Mao, Min; Yang, Guo-biao; Xiang, Yong-gang; Chen, Xin-mei

2009-08-01

To observe the formation of canal aberrations in S-shaped root canals prepared by every file of hand-used ProTaper. Fifteen S-shaped simulated resin root canals were selected. Each root canal was prepared by every file of hand-used ProTaper following the manufacturer instruction. The images of canals prepared by S1, S2, F1, F2 and F3 were taken and stored, which were divided into group S1, S2, F1, F2 and F3. One image of canal unprepared was superposed with the images of the same root canal in these five groups respectively to observe the types and number of canal aberrations, which included unprepared area, danger zone, ledge, elbow, zip and perforation. SPSS12.0 software pakage was used for Fisher's exact probabilities in 2x2 table. Unprepared area decreased following preparation by every file of ProTaper, but it still existed when the canal preparation was finished. The incidence of danger zone, elbow and zip in group F1 was 15/15, 11/15, 4/15, respectively, which was significantly higher than that in group S2(2/15,0,0) (P<0.001). Ledge appeared after prepared by F2, and increased sharply in group F3. None perforation was found in all groups. The incidence of canal aberrations begins to increase after prepared by finishing files of ProTaper.The presence of unprepared area suggests that it is essential to rinse canal abundantly during complicated canal preparation and canal antisepsis after preparation.

Histobacteriologic Conditions of the Apical Root Canal System and Periapical Tissues in Teeth Associated with Sinus Tracts.

PubMed

Ricucci, Domenico; Loghin, Simona; Gonçalves, Lucio S; Rôças, Isabela N; Siqueira, José F

2018-03-01

This histobacteriologic study described the pattern of intraradicular and extraradicular infections in teeth with sinus tracts and chronic apical abscesses. The material comprised biopsy specimens from 24 (8 untreated and 16 treated) roots of teeth associated with apical periodontitis and a sinus tract. Specimens were obtained by periradicular surgery or extraction and were processed for histobacteriologic and histopathologic methods. Bacteria were found in the apical root canal system of all specimens, in the main root canal (22 teeth) and within ramifications (17 teeth). Four cases showed no extraradicular infection. Extraradicular bacteria occurred as a biofilm attached to the outer root surface in 17 teeth (5 untreated and 12 treated teeth), as actinomycotic colonies in 2 lesions, and as planktonic cells in 2 lesions. Extraradicular calculus formation (mineralized biofilm) was evident in 10 teeth. Teeth with chronic apical abscesses and sinus tracts showed a very complex infectious pattern in the apical root canal system and periapical lesion, with a predominance of biofilms. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Anal Canal Gas Gangrene in Aplastic Anaemia: Rare yet Lethal Entity - A Caveat.

PubMed

Sudharsanan, Sundaramurthi; Vijayakumar, Chellappa; Manish, Kumar; Elamurugan, T P; Manwar, Ali S

2017-07-13

Gas gangrene is one of the most serious infections of traumatic and surgical wounds. The importance lies in the fact that, if not managed at the right time, the condition is fatal. Though perianal cellulitis and gangrene are commonly reported in immunocompromised patients, we report the case of a patient with gas gangrene involving only the anal canal extending to the rectum, a rare presentation to be reported in literature.  An 18-year-old lady, a patient of aplastic anaemia - immunodeficiency, developed gas gangrene of the anal canal possibly due to faecal contamination of anal fissures. The patient was managed with surgical debridement and intravenous antibiotics.  The clinical manifestations of gas gangrene are due to the liberation of toxins by Clostridium perfringens. The infection spreads rapidly and results in necrosis and devitalisation of tissues, unless intervened surgically. The clinical manifestations are more rapid and a high index of suspicion is needed for the diagnosis.

Anal Canal Gas Gangrene in Aplastic Anaemia: Rare yet Lethal Entity - A Caveat

PubMed Central

Sudharsanan, Sundaramurthi; Vijayakumar, Chellappa; Manish, Kumar; Elamurugan, TP

2017-01-01

Gas gangrene is one of the most serious infections of traumatic and surgical wounds. The importance lies in the fact that, if not managed at the right time, the condition is fatal. Though perianal cellulitis and gangrene are commonly reported in immunocompromised patients, we report the case of a patient with gas gangrene involving only the anal canal extending to the rectum, a rare presentation to be reported in literature.  An 18-year-old lady, a patient of aplastic anaemia - immunodeficiency, developed gas gangrene of the anal canal possibly due to faecal contamination of anal fissures. The patient was managed with surgical debridement and intravenous antibiotics.  The clinical manifestations of gas gangrene are due to the liberation of toxins by Clostridium perfringens. The infection spreads rapidly and results in necrosis and devitalisation of tissues, unless intervened surgically. The clinical manifestations are more rapid and a high index of suspicion is needed for the diagnosis. PMID:28936381

Diversity of human papillomavirus in the anal canal of men: The HIM study

PubMed Central

Sichero, Laura; Nyitray, Alan G.; Nunes, Emily Montosa; Nepal, Bal; Ferreira, Silvaneide; Sobrinho, João S.; Baggio, Maria Luiza; Galan, Lenice; Silva, Roberto C.; Lazcano-Ponce, Eduardo; Giuliano, Anna R.; Villa, Luisa L.

2015-01-01

Human papillomavirus (HPV) infections are associated with development of anogenital lesions in men. There are no reports describing the distribution of non-alpha HPV types in the anal canal of a sexually diverse men group. The HIM (HPV in Men) Study is a multicenter study of the natural history of HPV infection in Brazil, Mexico and USA. At baseline, 12% of anal canal specimens PCR HPV-positive were not typed by the Roche Linear Array and were considered unclassified. Our goal was characterizing HPVs among these unclassified specimens at baseline and assess associations with participant socio-demographic and behavioral characteristics. Unclassified HPVs were typed by sequencing amplified PGMY09/11 products or cloning of PGMY/GP+ nested amplicons followed by sequencing. Further analysis was conducted using FAP primers. Of men with unclassified HPV at the anal canal, most (89.1%) were men who have sex with women (MSW). Readable sequences were produced for 62.8% of unclassified specimens, of which 75.2% were characterized HPV types. A total of 18, 26, and 3 different α-, β- and γ-HPV types were detected, respectively. Compared to older men (45-70 years), α-HPVs were more commonly detected among young men (18-30 years) whereas β-HPVs were more frequent among mid-adult men (31-44 years). β-HPVs were more common among heterosexual men (85.0%) than non-heterosexual men. β2-HPV types composed all β-HPVs detected among non-heterosexual men. The high prevalence of β-HPV in the anal canal of men who do not report receptive anal sex is suggestive of other forms of transmission that do not involve penile-anal intercourse. PMID:25698660

Mandibular first premolar with four canals.

PubMed

Du, Yi; Lee, Angeline H C; Zhang, Chengfei

2013-02-01

A case of endodontic treatment of a mandibular first premolar exhibiting a total of four distinct root canals and four apical foramina is described. This occurrence in mandibular first premolar has rarely been reported in the endodontic literature. Endodontic treatment that considers the anatomic variation of root canal morphology is important to ensure a favorable healing outcome, and its identification could be enhanced by careful examination using a dental operating microscope. Obturation of root canals using a warm vertical compaction technique with a highly-radiopaque root canal sealer, such as AH Plus, after careful ultrasonic activated irrigation with ethylenediaminetetraacetic acid might allow the flow of sealer into the narrowed but unprepared part of the canal. This offers valuable adjuncts for the successful negotiation of calcified main canals, thereby facilitating optimum chemo-mechanical debridement of the root canal system. © 2013 Blackwell Publishing Asia Pty Ltd.

Isolation and identification of Enterococcus faecalis from necrotic root canals using multiplex PCR.

PubMed

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).

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

PubMed Central

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 ProTaper and K3XF groups when compared to LSX group. Canal transportation was significantly more (P < 0.05) in ProTaper group when compared to K3XF and LSX groups. There was no significant difference (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

CT detection of facial canal dehiscence and semicircular canal fistula: Comparison with surgical findings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fuse, Takeo; Tada, Yuichiro; Aoyagi, Masaru

1996-03-01

The purpose of this study was to determine the accuracy of high resolution CT (HRCT) in the detection of facial canal dehiscence and semicircular canal fistula, the preoperative evaluation of both of which is clinically very important for ear surgery. We retrospectively reviewed the HRCT findings in 61 patients who underwent mastoidectomy at Yamagata University between 1989 and 1993. The HRCT images were obtained in the axial and semicoronal planes using 1 mm slice thickness and 1 mm intersection gap. In 46 (75%) of the 61 patients, the HRCT image-based assessment of the facial canal dehiscence coincided with the surgicalmore » findings. The data for the facial canal revealed sensitivity of 66% and specificity of 84%. For semicircular canal fistula. in 59 (97%) of the 61 patients, the HRCT image-based assessment and the surgical findings coincided. The image-based assessment in the remaining two patients, who both had massive cholesteatoma, was false-positive. HRCT is useful in the diagnosis of facial canal dehiscence and labyrinthine fistula, but its limitations should also be recognized. 12 refs., 3 figs., 6 tabs.« less

Effect of photodynamic therapy (PDT) on Enterococcus faecalis biofilm in experimental primary and secondary endodontic infections.

PubMed

Tennert, Christian; Feldmann, Katharina; Haamann, Edwina; Al-Ahmad, Ali; Follo, Marie; Wrbas, Karl-Thomas; Hellwig, Elmar; Altenburger, Markus J

2014-11-04

To determine the antibacterial effect of photodynamic Therapy on Enterococcus faecalis (E. faecalis) biofilms in experimentally infected human root canals in primary infections and endodontic retreatments. One hundred and sixty single-rooted extracted teeth with one root canal were prepared using ProTaper instruments. Seventy specimens were left without root canal filling and autoclaved. The root canals of another 70 specimens were filled with Thermafil and AH Plus and the root canal fillings were removed after 24 hours using ProTaper D files and plasma sterilized. The specimens were infected with a clinical isolate of E. faecalis for 72 hours. Samples were taken using sterile paper points to determine the presence of E. faecalis in the root canals. The specimens were randomly divided into groups according to their treatment with 20 teeth each and a control. In the PDT group the teeth were treated using PDT, consisting of the photosensitizer toluidine blue and the PDT light source at 635 nm. In the NaOCl (sodium hypochlorite) group the root canals were rinsed with 10 mL of 3% NaOCl. In the NaOCl-PDT group the root canals were rinsed with 10 mL of 3% of sodium hypochlorite and then treated with PDT. Samples were taken after treatments using sterile paper points. Additionally, remaining root canal filling material was recovered from the root canal walls. Survival fractions of the samples were calculated by counting colony-forming units. A one-way analysis of variance (ANOVA) was applied to the data to assess the effect of different treatment techniques. Antimicrobial treatment of root canals caused a significant reduction of bacterial load in all groups. NaOCl irrigation eliminated E. faecalis most effectively. PDT alone was less effective compared to NaOCl irrigation and the combination of NaOCl irrigation and PDT. CFU levels recovered from the filling material after NaOCl irrigation of the root canals were 10fold higher compared to PDT and the combination of Na

Antibacterial Efficacy of a New Sonic Irrigation Device for Root Canal Disinfection.

PubMed

Neuhaus, Klaus W; Liebi, Melanie; Stauffacher, Simone; Eick, Sigrun; Lussi, Adrian

2016-12-01

Passive ultrasonic irrigation (PUI) is the most widespread method used to activate irrigation solutions. Concerns have been raised that PUI is less effective in curved root canals and is not passive at all. Our aim was to compare a novel passive sonic irrigation (PSI) device (6000 Hz) with PUI and manual irrigation (MI) with respect to their efficiency in removing different endodontic microorganisms from curved and straight root canals. We performed 2 experiments as follows. In a 3-day infection model, we included 8 groups of single or dual microbial species that were rinsed with 0.9% sodium chloride using PSI, PUI, or MI. Colony-forming units (CFUs) were counted after incubation, and log 10 transformations were performed for statistical comparisons. In a 21-d infection model, we tested the same irrigation protocols on 4 groups of microorganisms and used 1.5% sodium hypochlorite as an irrigant. Infection control samples were taken at day 0, 3, 5, and 7 after treatment and were subsequently reincubated. Using sodium chloride as an irrigant, the amount of reduction in CFUs compared with the negative control was approximately 3 log 10 units for PSI at 6000 Hz, 2 log 10 units for PUI, and 1 log 10 unit for MI. PSI reduced the microorganism CFUs significantly better than PUI. Using sodium hypochlorite led to a significant reduction in microorganism CFUs even with MI. After 3 days, compared with MI, microorganism regrowth significantly reduced after PSI and PUI treatment, but in these groups, in at least half of the samples, microorganisms were detectable after 7 days. PSI at 6000 Hz might be at least equal to PUI with respect to reduction of the microbial load in curved and straight root canals. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Your baby in the birth canal

MedlinePlus

... lie; Fetal attitude; Fetal descent; Fetal station; Cardinal movements; Labor-birth canal; Delivery-birth canal ... are used to describe your baby's position and movement through the birth canal. FETAL STATION Fetal station ...

Love Canal: environmental and toxicological studies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, C.S.

The New York State Department of Health has been involved at the Love Canal since 1978. The State has carried out numerous environmental and toxicological studies. The major purposes for these studies were to define how Love Canal contaminants might be escaping into the environment at large, what paths contaminant migration might take, and what toxicological effects Love Canal chemicals might have individually and together. Although underground contaminant migration was hypothesized along swales and underground utility bedding, these mechanisms have been proven not to be operative except for some migration along the utility bedding under Frontier Avenue. In general nomore » underground migration has occurred outside the confines of the three city blocks that contain the Love Canal referred to as the ''first ring''. Studies have been confused by apparent burial of waste materials in areas proximate but not directly connected to the Love Canal. Migration of Love Canal leachate has occurred through storm sewers. Love Canal contaminants have reached creeks to the north and the Niagara River to the south through storm sewer transport. In spite of finding 2, 3, 7, 8 tetrachlorodibenzoparadioxin (TCDD), toxicological studies in situ and through exposure to volatile components in Love Canal soils do not indicate unusual toxicity. Animal studies continue in an attempt to determine the teratogenic and fetotoxic potential of Love Canal chemicals under different routes of exposure.« less

Impact of cross-sectional root canal shape on filled canal volume and remaining root filling material after retreatment.

PubMed

Rechenberg, D K; Paqué, F

2013-06-01

To assess the impact of cross-sectional root canal shape (CSRCS) on the canal volume that can be filled and the root filling material that remains following a subsequent retreatment procedure. A total of 15 extracted two-rooted human maxillary premolars and 15 mandibular first molars were used. Both root canals in the premolars (N = 30) and the distal root canal in the molars (N = 15) were prepared using ProFile instruments and filled by lateral compaction using gutta-percha and AH Plus sealer. Canals were later retreated using the last ProFile used for instrumentation followed by two ProFiles of increasing size. Teeth were viewed in a μCT scanner before and after each treatment step. Defined and validated threshold levels were used to differentiate empty root canal volumes, root dentine and root filling materials from each other. CSRCS was defined as the averaged ratio between bucco-lingual and mesio-distal canal diameter (round ≤ 1, oval 1-2, long oval 2-4 and flattened ≥ 4), determined for each 1 mm over the total root length. Data were averaged between the two canals in premolars, only the distal canals were assessed in molars. Parametric and non-parametric tests were used to statistically compare the data, alpha = 0.01. Canals in premolars had a round CSRCS after preparation (1.0 ± 0.0), whereas distal counterparts in molars were oval (1.6 ± 0.5). Significantly (P < 0.01) more canal volume could be filled, and significantly less filling material remained after retreatment in premolars compared with mandibular molar distal canals. There was a high correlation between CSRCS, filled canal volume and remaining filling material. The endodontic procedures under investigation were significantly influenced by the cross-sectional root canal shape. © 2012 International Endodontic Journal. Published by Blackwell Publishing Ltd.

Combined Antibacterial Effect of Sodium Hypochlorite and Root Canal Sealers against Enterococcus faecalis Biofilms in Dentin Canals.

PubMed

Du, Tianfeng; Wang, Zhejun; Shen, Ya; Ma, Jingzhi; Cao, Yingguang; Haapasalo, Markus

2015-08-01

The present study aimed to evaluate the antibacterial effect of the combined use of sodium hypochlorite (NaOCl) and root canal sealers on Enterococcus faecalis biofilms using a dentin infection model. Cells of E. faecalis were introduced into the dentinal tubules by centrifugation and incubated in brain-heart infusion for 3 weeks. The biofilms in dentin were first subjected to 5% NaOCl or sterile water for 10 minutes followed by an equal thickness of AH Plus (Dentsply International Inc, York, PA), Endosequence BC Sealer (Brasseler USA, Savannah, GA), or MTA Fillapex (Angelus Indústria de Produtos Odontológicos S/A, Londrina, Brazil) placed on the root canal wall of the dentin specimens for 7, 30, and 60 days. Gutta-percha and water were used in a similar manner as controls. The proportions of dead and live bacteria inside the dentinal tubules were assessed by confocal laser scanning microscopy and viability staining. The combined use of NaOCl and sealers (30 and 60 days) killed significantly more bacteria than NaOCl or sealers alone (P < .05). NaOCl + MTA Fillapex was the most effective antibacterial combination by killing 83% bacteria in dentin tubules in 60 days. Thirty and 60 days of exposure to the sealers resulted in significantly more dead bacteria in dentin biofilms than 7-day exposures (P < .05). The placement of root canal sealer after NaOCl treatment enhanced antibacterial effects against E. faecalis in the dentinal tubules. Little additional effect was obtained after 30 days of exposure to sealers. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Hypoglossal canal size and hominid speech

PubMed Central

DeGusta, David; Gilbert, W. Henry; Turner, Scott P.

1999-01-01

The mammalian hypoglossal canal transmits the nerve that supplies the motor innervation to the tongue. Hypoglossal canal size has previously been used to date the origin of human-like speech capabilities to at least 400,000 years ago and to assign modern human vocal abilities to Neandertals. These conclusions are based on the hypothesis that the size of the hypoglossal canal is indicative of speech capabilities. This hypothesis is falsified here by the finding of numerous nonhuman primate taxa that have hypoglossal canals in the modern human size range, both absolutely and relative to oral cavity volume. Specimens of Australopithecus afarensis, Australopithecus africanus, and Australopithecus boisei also have hypoglossal canals that, both absolutely and relative to oral cavity volume, are equal in size to those of modern humans. The basis for the hypothesis that hypoglossal canal size is indicative of speech was the assumption that hypoglossal canal size is correlated with hypoglossal nerve size, which in turn is related to tongue function. This assumption is probably incorrect, as we found no apparent correlation between the size of the hypoglossal nerve, or the number of axons it contains, and the size of the hypoglossal canal in a sample of cadavers. Our data demonstrate that the size of the hypoglossal canal does not reflect vocal capabilities or language usage. Thus the date of origin for human language and the speech capabilities of Neandertals remain open questions. PMID:9990105

Pulp regeneration after non-infected and infected necrosis, what type of tissue do we want? A review.

PubMed

Andreasen, Jens O; Bakland, Leif K

2012-02-01

Regeneration (revitalization) of infected necrotic pulp tissue has been an important issue in endodontics for more than a decade. Based on a series of case reports, there appears to be evidence that new soft tissue can enter the root canal with a potential for subsequent hard tissue deposition resulting in a narrowing of the root canal. Very little is presently known about the exact nature of this tissue growing into the canal and how it may behave in the long term. In the case of regeneration of necrotic non-infected pulp tissue, a series of clinical and histological studies have shown that such events may take place in four variants: (i) Revascularization of the pulp with accelerated dentin formation leading to pulp canal obliteration. This event has a good long-term prognosis. (ii) Ingrowth of cementum and periodontal ligament (PDL). The long-term prognosis for this event is not known. (iii) Ingrowth of cementum, PDL, and bone. The long-term prognosis is only partly known, but cases developing an internal ankylosis have been described. (iv) Ingrowth of bone and bone marrow is a rare phenomenon and the long-term prognosis does not appear to be good. Based on current knowledge, expectations with respect to pulp regeneration (revitalization) of infected necrotic dental pulps are difficult to predict; more information than now available is needed before procedures for pulpal regeneration can be routinely recommended with a predictable long-term prognosis. © 2011 John Wiley & Sons A/S.

Craniopharyngeal canal and its spectrum of pathology.

PubMed

Abele, T A; Salzman, K L; Harnsberger, H R; Glastonbury, C M

2014-04-01

The craniopharyngeal canal is a rare, well-corticated defect through the midline of the sphenoid bone from the sellar floor to the anterosuperior nasopharyngeal roof. We reviewed a series of craniopharyngeal canals to determine a system of classification that might better our understanding of this entity, highlight the range of associated pathologic conditions, and optimize patient treatment. Available MR imaging, CT, and clinical data (from 1989-2013) of 29 patients (10 female, 15 male, 4 unknown; median age, 4 years; age range, 1 day-65 years) with craniopharyngeal canals were retrospectively examined. Qualitative assessment included orthotopic or ectopic adenohypophysis and the presence of a tumor and/or cephalocele. The midpoint anteroposterior diameter was measured. Clinical and imaging data were evaluated for pituitary dysfunction and accompanying anomalies. Craniopharyngeal canals were qualitatively separated into 3 types: incidental canals (type 1); canals with ectopic adenohypophysis (type 2); and canals containing cephaloceles (type 3A), tumors (type 3B), or both (type 3C), including pituitary adenoma, craniopharyngioma, dermoid, teratoma, and glioma. Quantitative evaluation showed a significant difference (P < .0001) in the anteroposterior diameters of type 1 canals (median, 0.8; range, 0.7-1.1 mm), type 2 canals (median, 3.9, range, 3.5-4.4 mm), and type 3 canals (median, 9.0; range, 5.9-31.0 mm) imparting small, medium, and large descriptors. Canals with cephaloceles all contained an ectopic adenohypophysis. The craniopharyngeal canals were associated with pituitary dysfunction (6/29) and congenital anomalies (8/29). Accurate diagnosis and classification of craniopharyngeal canals are valuable to characterize lesions requiring surgery, identify patients with potential pituitary dysfunction, and avoid iatrogenic hypopituitarism or CSF leak during surgical resection of nasopharyngeal masses.

Herpes zoster sciatica mimicking lumbar canal stenosis: a case report.

PubMed

Koda, Masao; Mannoji, Chikato; Oikawa, Makiko; Murakami, Masazumi; Okamoto, Yuzuru; Kon, Tamiyo; Okawa, Akihiko; Ikeda, Osamu; Yamazaki, Masashi; Furuya, Takeo

2015-07-29

Symptom of herpes zoster is sometimes difficult to distinguish from sciatica induced by spinal diseases, including lumbar disc herniation and spinal canal stenosis. Here we report a case of sciatica mimicking lumbar canal stenosis. A 74-year-old Chinese male patient visited our hospital for left-sided sciatic pain upon standing or walking for 5 min of approximately 1 month's duration. At the first visit to our hospital, there were no skin lesions. A magnetic resonance imaging showed spinal canal stenosis between the 4th and 5th lumbar spine. Thus, we diagnosed the patient with sciatica induced by spinal canal stenosis. We considered decompression surgery for the stenosis of 4th and 5th lumbar spine because conservative therapy failed to relieve the patient's symptom. At that time, the patient complained of a skin rash involving his left foot for several days. A vesicular rash and erythema were observed on the dorsal and plantar surfaces of the great toe and lateral malleolus. The patient was diagnosed with herpes zoster in the left 5th lumbar spinal nerve area based on clinical findings, including the characteristics of the pain and vesicular rash and erythema in the 5th lumbar spinal dermatome. The patient was treated with famciclovir (1,500 mg/day) and non-steroidal anti-inflammatory drugs. After 1 week of medication, the skin rash resolved and pain relief was obtained. In conclusion, spinal surgeons should keep in mind herpes zoster infection as one of the possible differential diagnoses of sciatica, even if there is no typical skin rash.

Glaser Fissure, Huguier Canal, and Civinini Canal: A Confused Eponymical Imbroglio.

PubMed

Mudry, Albert

2015-07-01

Huguier canal or Civinini canal is a canaliculus in the Glaser fissure allowing the exit of the chorda tympani from the tympanic cavity. The aim of this study is to try to put some order in the origins and relations of these different eponyms, and to evaluate their pertinence in the actual anatomical terminology. This study demonstrates that Huguier and Civinini are not the first to describe this canal in the 1830s. Furthermore, it confirms that Glaser does not describe the related fissure in 1680. In conclusion, Glaser, Civinini, and Huguier no longer have a place in the actual anatomical nomenclature of the fine details of the temporal bone. To avoid confusion and errors, they must be replaced by anterior canaliculus for the chorda tympani and petrotympanic fissure.

Distributed control at Love canal

DOE Office of Scientific and Technical Information (OSTI.GOV)

McPherson, G.; Rider, G.J.; Sadowski, B.

Love Canal is known worldwide as the site of one of the worst non-nuclear environmental disasters in modern history. For 12 years, a Niagara Falls, New York chemical company used the canal bed as a chemical dump. This article discusses the computerized control of equipment used to remove the toxic materials from the ground under Love Canal, and how the minimization of maintenance is reducing maintenance costs and increasing operator safety.

Canal Transportation and Centering Ability of ProTaper and SafeSider in Preparation of Curved Root Canals: A CBCT Evaluation

PubMed Central

Delgoshayi, Negar; Abbasi, Mansoure; Bakhtiar, Hengameh; Sakhdari, Shirin; Ghannad, Setareh; Ellini, Mohammad Reza

2018-01-01

Introduction: Maintaining the original central canal path is an important parameter in efficient root canal preparation. Instruments causing minimal changes in original canal path are preferred for this purpose. This study sought to compare canal transportation and centering ability of ProTaper and SafeSider instruments in curved mesiobuccal root canals of mandibular first molars using cone beam computed tomography (CBCT). Methods and Materials : In this experimental study, 30 mesiobuccal root canals of extracted human mandibular first molars with 20° to 40° curvature were randomly divided into two groups (n=15). After mounting in putty, preoperative CBCT scans were obtained of teeth. Root canals in group A were shaped using S1, S2, F1 and F2 of ProTaper system. Root canals in group B were instrumented to size 25 using SafeSider system according to the manufacturers’ instructions. Postoperative CBCT scans were then obtained. The distance between the external root surface and internal canal wall was measured at the mesial and distal at 1, 3 and 7 mm from the apex. The values measured on primary and secondary CBCT scans were compared to assess possible changes in original central canal path and canal transportation. Data were compared using the t-test and repeated measure ANOVA. Results: ProTaper and SafeSider were significantly different in terms of canal transportation and centering ability, and ProTaper was significantly superior to SafeSider in this respect (P<0.001). Conclusion: ProTaper (in contrast to SafeSider) is well capable of maintaining the original central canal path with the least amount of transportation. PMID:29707022

Increased malaria transmission around irrigation schemes in Ethiopia and the potential of canal water management for malaria vector control.

PubMed

Kibret, Solomon; Wilson, G Glenn; Tekie, Habte; Petros, Beyene

2014-09-13

Irrigation schemes have been blamed for the increase in malaria in many parts of sub-Saharan Africa. However, proper water management could help mitigate malaria around irrigation schemes in this region. This study investigates the link between irrigation and malaria in Central Ethiopia. Larval and adult mosquitoes were collected fortnightly between November 2009 and October 2010 from two irrigated and two non-irrigated (control) villages in the Ziway area, Central Ethiopia. Daily canal water releases were recorded during the study period and bi-weekly correlation analysis was done to determine relationships between canal water releases and larval/adult vector densities. Blood meal sources (bovine vs human) and malaria sporozoite infection were tested using enzyme-linked immunosorbent assay (ELISA). Monthly malaria data were also collected from central health centre of the study villages. Monthly malaria incidence was over six-fold higher in the irrigated villages than the non-irrigated villages. The number of anopheline breeding habitats was 3.6 times higher in the irrigated villages than the non-irrigated villages and the most common Anopheles mosquito breeding habitats were waterlogged field puddles, leakage pools from irrigation canals and poorly functioning irrigation canals. Larval and adult anopheline densities were seven- and nine-fold higher in the irrigated villages than in the non-irrigated villages, respectively, during the study period. Anopheles arabiensis was the predominant species in the study area. Plasmodium falciparum sporozoite rates of An. arabiensis and Anopheles pharoensis were significantly higher in the irrigated villages than the non-irrigated villages. The annual entomological inoculation rate (EIR) calculated for the irrigated and non-irrigated villages were 34.8 and 0.25 P. falciparum infective bites per person per year, respectively. A strong positive correlation was found between bi-weekly anopheline larval density and canal water

Root canal volume change and transportation by Vortex Blue, ProTaper Next, and ProTaper Universal in curved root canals

PubMed Central

2018-01-01

Objectives The aim of this study was to compare root canal volume change and canal transportation by Vortex Blue (VB; Dentsply Tulsa Dental Specialties), ProTaper Next (PTN; Dentsply Maillefer), and ProTaper Universal (PTU; Dentsply Maillefer) nickel-titanium rotary files in curved root canals. Materials and Methods Thirty canals with 20°–45° of curvature from extracted human molars were used. Root canal instrumentation was performed with VB, PTN, and PTU files up to #30.06, X3, and F3, respectively. Changes in root canal volume before and after the instrumentation, and the amount and direction of canal transportation at 1, 3, and 5 mm from the root apex were measured by using micro-computed tomography. Data of canal volume change were statistically analyzed using one-way analysis of variance and Tukey test, while data of amount and direction of transportation were analyzed using Kruskal-Wallis and Mann-Whitney U test. Results There were no significant differences among 3 groups in terms of canal volume change (p > 0.05). For the amount of transportation, PTN showed significantly less transportation than PTU at 3 mm level (p = 0.005). VB files showed no significant difference in canal transportation at all 3 levels with either PTN or PTU files. Also, VB files showed unique inward transportation tendency in the apical area. Conclusions Other than PTN produced less amount of transportation than PTU at 3 mm level, all 3 file systems showed similar level of canal volume change and transportation, and VB file system could prepare the curved canals without significant shaping errors. PMID:29487834

The effect of sodium hypochlorite and ginger extract on microorganisms and endotoxins in endodontic treatment of infected root canals.

PubMed

Valera, Marcia Carneiro; Maekawa, Lilian Eiko; Chung, Adriana; Cardoso, Flavia Goulart Rosa; Oliveira, Luciane Dias de; Oliveira, Carolina Lima de; Carvalho, Claudio Antonio Talge

2014-01-01

This in vitro study sought to evaluate the biomechanical preparation action on microorganisms and endotoxins by using sodium hypochlorite (NaOCl) and an intracanal medication containing Zingiber officinale, with or without calcium hydroxide. Single-rooted teeth were contaminated, and root canal instrumentation (using 2.5% NaOCl) was performed. Samples were divided into 4 groups, according to the intracanal medication employed. The root canal content was gathered 28 days after contamination (baseline), immediately after biomechanical preparation, 7 days after biomechanical preparation, 14 days after intracanal medication, and 7 days after intracanal medication was removed. The results (submitted to Kruskal-Wallis and Dunn tests) showed that the NaOCl eliminated 100% of root canal microorganisms and reduced 88.8% of endotoxins immediately after biomechanical preparation, and 83.2% at 7 days after biomechanical preparation.

Black-pigmented gram-negative anaerobes in endodontic infections.

PubMed

Haapasalo, M

1993-03-01

Necrotic dental root canal infections are polymicrobial infections dominated by anaerobic bacteria. The number of different species in one canal is usually low, approx. 4-7 species. The species isolated most frequently belong to the genera Prevotella, Porphyromonas, Fusobacterium, Peptostreptococcus, Eubacterium and Streptococcus. The frequency of isolation of black-pigmented Gram-negative anaerobes in endodontic infections varies from 25% to > 50%. Pr. intermedia is the most commonly found pigmented species, followed by Pr. denticola and two Porphyromonas species, P. gingivalis and P. endodontalis. Several studies have shown that P. gingivalis and P. endodontalis are closely related to the presence of acute symptoms in endodontic infections, whereas other black-pigmented Gram-negative anaerobes are not. However, several other species may also be involved in acute infections. Moreover, Porphyromonas species have occasionally been isolated from cases with no symptoms. Although Porphyromonas spp. are clearly related to symptoms at the beginning of therapy, they are not important for the prognosis of the treatment.

Canal Aberration Assessment in Simulated Root Canals: a Comparative Study

PubMed Central

Jakupovic, Selma; Konjhodzic, Alma; Brankovic, Lajla Hasic; Korac, Samra; Tahmiscija, Irmina; Dzankovic, Aida; Glamoc, Alma Gavranovic

2017-01-01

Aim: The aim of this study was to compare time of preparation and canal aberrations in a simulated root canals after using three different rotary systems: Endostar E5, Endostar E3 and T One File Gold. Materials and Methods: A total of 90 endodontic training blocks were used in this study and divided into three groups consisting of 30 each (n = 30). Blocks processing was performed by thirty dentists without any prior experience in rotary instrumentation techniques. In the first group blocks were prepared using Endostar E5, in second one with Endostar E3 and in third one with T One File Gold system. The preparation time was measured. The postoperative image of each block was taken by stereomicroscope and canal aberrations (ledge and instrument fracture) was recorded. Statistical analysis was done by SPSS software. Results: Instrumentation with T One File Gold system is significantly faster compared to instrumentation with Endostar E5 and Endostar E3 systems (p <0.05). There are no statistically significant differences in the type and number of procedural errors between Endostar E5, Endostar E3 and T One File Gold systems when the operators have no previous experience in rotary instrumentation techniques. Conclusion: Under the conditions of this study, the incidence of examined canal aberrations were similar for all tested systems. The preparation time was significantly shorter with single file system. PMID:28974834

Dorello's Canal for Laymen: A Lego-Like Presentation.

PubMed

Ezer, Haim; Banerjee, Anirban Deep; Thakur, Jai Deep; Nanda, Anil

2012-06-01

Objective Dorello's canal was first described by Gruber in 1859, and later by Dorello. Vail also described the anatomy of Dorello's canal. In the preceding century, Dorello's canal was clinically important, in understanding sixth nerve palsy and nowadays it is mostly important for skull base surgery. The understanding of the three dimensional anatomy, of this canal is very difficult to understand, and there is no simple explanation for its anatomy and its relationship with adjacent structures. We present a simple, Lego-like, presentation of Dorello's canal, in a stepwise manner. Materials and Methods Dorello's canal was dissected in five formalin-fixed cadaver specimens (10 sides). The craniotomy was performed, while preserving the neural and vascular structures associated with the canal. A 3D model was created, to explain the canal's anatomy. Results Using the petrous pyramid, the sixth nerve, the cavernous sinus, the trigeminal ganglion, the petorclival ligament and the posterior clinoid, the three-dimensional structure of Dorello's canal was defined. This simple representation aids in understanding the three dimensional relationship of Dorello's canal to its neighboring structures. Conclusion Dorello's canal with its three dimensional structure and relationship to its neighboring anatomical structures could be reconstructed using a few anatomical building blocks. This method simplifies the understanding of this complex anatomical structure, and could be used for teaching purposes for aspiring neurosurgeons, and anatomy students.

Dorello's Canal for Laymen: A Lego-Like Presentation

PubMed Central

Ezer, Haim; Banerjee, Anirban Deep; Thakur, Jai Deep; Nanda, Anil

2012-01-01

Objective Dorello's canal was first described by Gruber in 1859, and later by Dorello. Vail also described the anatomy of Dorello's canal. In the preceding century, Dorello's canal was clinically important, in understanding sixth nerve palsy and nowadays it is mostly important for skull base surgery. The understanding of the three dimensional anatomy, of this canal is very difficult to understand, and there is no simple explanation for its anatomy and its relationship with adjacent structures. We present a simple, Lego-like, presentation of Dorello's canal, in a stepwise manner. Materials and Methods Dorello's canal was dissected in five formalin-fixed cadaver specimens (10 sides). The craniotomy was performed, while preserving the neural and vascular structures associated with the canal. A 3D model was created, to explain the canal's anatomy. Results Using the petrous pyramid, the sixth nerve, the cavernous sinus, the trigeminal ganglion, the petorclival ligament and the posterior clinoid, the three-dimensional structure of Dorello's canal was defined. This simple representation aids in understanding the three dimensional relationship of Dorello's canal to its neighboring structures. Conclusion Dorello's canal with its three dimensional structure and relationship to its neighboring anatomical structures could be reconstructed using a few anatomical building blocks. This method simplifies the understanding of this complex anatomical structure, and could be used for teaching purposes for aspiring neurosurgeons, and anatomy students. PMID:23730547

Application of software for automated canal management (SacMan) to the WM lateral canal

USDA-ARS?s Scientific Manuscript database

Simulation studies have demonstrated that automatic control of canals is more effective when feedforward scheduling, or routing of know demand changes, is combined with centralized, automatic, distant, downstream-water-level control. In practice, few canals use this approach. To help further develop...

Semiconductor laser irradiation improves root canal sealing during routine root canal therapy

PubMed Central

Hu, Xingxue; Wang, Dashan; Cui, Ting; Yao, Ruyong

2017-01-01

Objective To evaluate the effect of semiconductor laser irradiation on root canal sealing after routine root canal therapy (RCT). Methods Sixty freshly extracted single-rooted human teeth were randomly divided into six groups (n = 10). The anatomic crowns were sectioned at the cementoenamel junction and the remaining roots were prepared endodontically with conventional RCT methods. Groups A and B were irradiated with semiconductor laser at 1W for 20 seconds; Groups C and D were ultrasonically rinsed for 60 seconds as positive control groups; Groups E and F without treatment of root canal prior to RCT as negative control groups. Root canal sealing of Groups A, C and E were evaluated by measurements of apical microleakage. The teeth from Groups B, D and F were sectioned, and the micro-structures were examined with scanning electron microscopy (SEM). One way ANOVA and LSD-t test were used for statistical analysis (α = .05). Results The apical sealing of both the laser irradiated group and the ultrasonic irrigated group were significantly different from the control group (p<0.5). There was no significant difference between the laser irradiated group and the ultrasonic irrigated group (p>0.5). SEM observation showed that most of the dentinal tubules in the laser irradiation group melted, narrowed or closed, while most of the dentinal tubules in the ultrasonic irrigation group were filled with tooth paste. Conclusion The application of semiconductor laser prior to root canal obturation increases the apical sealing of the roots treated. PMID:28957407

Effect of rotary instrumentation and of the association of calcium hydroxide and chlorhexidine on the antisepsis of the root canal system in dogs.

PubMed

Soares, Janir Alves; Leonardo, Mario Roberto; da Silva, Léa Assed Bezerra; Tanomaru Filho, Mario; Ito, Izabel Yoko

2006-01-01

This study aimed at evaluating the antisepsis of the root canal system (RCS) and periapical region (PR) provided by rotary instrumentation associated with chlorhexidine + calcium hydroxide as intracanal medicament. Chronic periapical lesions were induced in 26 pre-molar roots in two dogs. After microbiological sampling, automatic instrumentation using the Profile system and irrigation with 5.25% sodium hypochlorite solution, with a final rinse of 14.3% EDTA followed by profuse irrigation with physiological saline were carried out in 18 root canals. After drying the canals, a paste based on calcium hydroxide associated with a 2% chlorhexidine digluconate solution was placed inside them. After 21 days, the medication was removed, leaving the root canals empty and coronally sealed. After 96 hours, a final microbiological sample was obtained, followed by histomicrobiological processing by the Brown & Brenn method. Eight untreated root canals represented the control group (C-G). Based on the Mann-Whitney test at a confidence level of 5% (p < 0.05), the procedures of antisepsis used offered significant efficacy (p < 0.05) resulting in 100.0% of the canals free of microorganisms. In the C-G, an elevated incidence of various microbial morphotypes was confirmed in all sites of the RCS, with the presence of microbial colonies in the periapical region. In contrast, the experimental group showed a similar pattern of infection in the RCS, although less intense and a reduced level of periapical infection (p < 0.05). It was concluded that adequate instrumentation followed by the application of calcium hydroxide + chlorhexidine offered significant elimination of microorganisms.

Mandibular incisive canal: cone beam computed tomography.

PubMed

Pires, Carlos A; Bissada, Nabil F; Becker, Jeffery J; Kanawati, Ali; Landers, Michael A

2012-03-01

Panoramic radiography is often used to analyze the anatomical structure of the teeth, jaws, and temporomandibular joints. Cone beam computed tomography (CBCT) imaging allows multiple axial slices of the image to be obtained through these anatomical structures. The aim of this study was to assess CBCT compared with panoramic radiography to verify the presence, location, and dimensions of the mandibular incisive canal. CBCT scan images and panoramic radiographs of 89 subjects were compared for the presence of the mandibular incisive canal, its location, size, and anterior-posterior length. The distance between the incisive canal and the buccal and lingual plate of the alveolar bone, and the distance from the canal to the inferior border of the mandible and the tooth apex were also measured. A paired t-test was used to calculate any significant difference between the two imaging techniques. Eighty-three percent of the CBCT scans showed the presence of the incisive canal, as did 11% of the panoramic radiographs. The range of the incisive canal diameter, as seen in the CBCT scans, was from 0.4 × 0.4 mm to 4.6 × 3.2 mm. The mean length of the canal was 7 ± 3.8 mm. The distance from the inferior border of the mandible to the canal was 10.2 ± 2.4 mm, and the mean distance to the buccal plate was 2.4 mm. The apex-canal distance (in dentate subjects) was 5.3 mm. The presence, location, and dimensions of the mandibular incisive canal are better determined by CBCT imaging than by panoramic radiography. © 2009 Wiley Periodicals, Inc.

The Semicircular Canal Microphonic

NASA Technical Reports Server (NTRS)

Rabbitt, R. D.; Boyle, R.; Highstein, S. M.; Dalton, Bonnie P. (Technical Monitor)

2002-01-01

Present experiments were designed to quantify the alternating current (AC) component of the semicircular canal microphonic for angular motion stimulation as a function of stimulus frequency and amplitude. The oyster toadfish, Opsanus tau, was used as the experimental model. Calibrated mechanical indentation of the horizontal canal duct was used as a stimulus to generate hair-cell and afferent responses reproducing those present during head rotation. Sensitivity to polarization of the endolymph DC voltage re: perilymph was also investigated. Modulation of endolymph voltage was recorded using conventional glass electrodes and lock-in amplification over the frequency range 0.2-80 Hz. Access to the endolymph for inserting voltage recording and current passing electrodes was obtained by sectioning the anterior canal at its apex and isolating the cut ends in air. For sinusoidal stimulation below approx.10 Hz, the horizontal semicircular canal AC microphonic was nearly independent of stimulus frequency and equal to approximately 4 microV per micron indent (equivalent to approx. 1 microV per deg/s). A saturating nonlinearity decreasing the microphonic gain was present for stimuli exceeding approx.3 micron indent (approx. 12 deg/s angular velocity). The phase was not sensitive to the saturating nonlinearity. The microphonic exhibited a resonance near 30Hz consistent with basolateral current hair cell resonance observed previously in voltage-clamp records from semicircular canal hair cells. The magnitude and phase of the microphonic exhibited sensitivity to endolymphatic polarization consistent with electro-chemical reversal of hair cell transduction currents.

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

PubMed Central

Rathi, Sushma; Patil, Jayaprakash; Jaju, Prashant P.

2010-01-01

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. PMID:20613946

Antimicrobial activity of different disinfection methods against biofilms in root canals.

PubMed

Gergova, Raina T; Gueorgieva, Tzvetelina; Dencheva-Garova, Mariya S; Krasteva-Panova, Assya Z; Kalchinov, Vasil; Mitov, Ivan; Kamenoff, Julia

2016-08-01

The aim of the present study was to evaluate the bactericidal effects of different disinfection methods against microbial biofilms grown in root canals. A total of 300 freshly-extracted human teeth were infected with microbial pathogens. The biofilm formation and the effects of laser therapy, photodynamic therapy (PDT), iontophoresis, and disinfection with irrigating solutions were evaluated by counting the generations of microbial cells in the samples of root canals and by scanning electron microscopy. Enterococcus faecalis and other Gram-positive cocci demonstrated highest sensitivity to the methods of antibacterial action compared here. In most of the cases observed, the antibacterial treatment was less effective against Gram-negative bacteria in dental biofilms. The biofilms that were most difficult to eliminate were those formed by Pseudomonas aeruginosa. Iontophoresis treatment with iodine and chemical disinfection with hypochlorite and chlorhexidine demonstrated the most powerful bactericidal effect. When PDT was applied with Fotosan as a photosensitizer, better disinfection was achieved in comparison to the other lasers alone. The comparison of these different strategies for endodontic treatment showed that hypochlorite, followed by the chlorhexidine irrigant in our experimental conditions, gave the most satisfactory results against the formation of bacterial biofilms in the root canals. © 2015 Wiley Publishing Asia Pty Ltd.

77 FR 42644 - Safety Zone; Canal Fest of the Tonawandas, Erie Canal, Tonawanda, NY

Federal Register 2010, 2011, 2012, 2013, 2014

2012-07-20

.... ACTION: Temporary final rule. SUMMARY: The Coast Guard is establishing a temporary safety zone on the... Canal during the Canal Fest of the Tonawandas Fireworks display. This temporary safety zone is necessary to protect spectators and vessels from the hazards associated with a fireworks display. DATES: This...

Water Environment Evolution along the China Grand Canal

NASA Astrophysics Data System (ADS)

Mao, F.; Wu, Y. X.; Yang, B. F.; Li, X. J.

2014-03-01

The China Grand Canal is one of the earliest canals in the world, having lasted for nearly 3000 years. Even its section canals have a rich history, such as the North-South Grand Canal that was established during the Sui Dynasty, whereas the Beijing-Hangzhou Canal was excavated during the Yuan Dynasty and the east line of the South-to-North Water Diversion. As one of the longest in the world, the China Grand Canal's total length is over 3500 kilometers. This length includes the navigable, unnavigable, and underground sections. Making the best use of situations and according to local conditions, the Chinese people harmoniously constructed the Beijing-Hangzhou Canal with nature. Tens of millions of workers took nearly 3000 years to complete the great shipping system. Navigable sections still exist for up to 900 kilometers and the volume of freight traffic is approximately 300 million tons. The canal remains the main logistical channel of the North-to-South Coal Transportation, South-to-North Water Diversion, and resources circulation. To date, China is promoting the success of heritage application. Part of these efforts is the declaration of the China Grand Canal as a World Cultural Heritage by 2014. In addition, the east route of the South-to-North Water Transfer project is planned to be navigable by 2016. The ancient Beijing-Hangzhou Grand Canal will usher in the new ecological civilization and cultural revival along the canal. This paper presents technical methods of water environment evolution research on the river system, river, and water quality along the Beijing-Hangzhou Canal through the integration of historical literature and modern remote sensing image data. The study carried out water environment investigation and analysis along the Beijing-Hangzhou canal by using ETM, SPOT image data, and GPS measurement data. Spatial and temporal evolution characteristics and regulations of the Beijing-Hangzhou Grand Canal regional water environment in the span of 3000

Developmental spinal canal stenosis and somatotype.

PubMed Central

Nightingale, S

1989-01-01

The hypothesis that somatotype and cervical spine developmental canal stenosis may be associated has been investigated by anthropometry and measurement of lateral projection cervical spine radiographs. A significant association of canal size with somatotype has been found such that those with developmentally narrow canals are more likely to have relatively shorter long-bones, particularly in the upper arm, and longer trunks. Images PMID:2769282

Proteomic signatures reveal a dualistic and clinically relevant classification of anal canal carcinoma.

PubMed

Herfs, Michael; Longuespée, Rémi; Quick, Charles M; Roncarati, Patrick; Suarez-Carmona, Meggy; Hubert, Pascale; Lebeau, Alizée; Bruyere, Diane; Mazzucchelli, Gabriel; Smargiasso, Nicolas; Baiwir, Dominique; Lai, Keith; Dunn, Andrew; Obregon, Fabiola; Yang, Eric J; Pauw, Edwin De; Crum, Christopher P; Delvenne, Philippe

2017-03-01

Aetiologically linked to HPV infection, malignancies of the anal canal have substantially increased in incidence over the last 20 years. Although most anal squamous cell carcinomas (SCCs) respond well to chemoradiotherapy, about 30% of patients experience a poor outcome, for undetermined reasons. Despite cumulative efforts for discovering independent predictors of overall survival, both nodal status and tumour size are still the only reliable factors predicting patient outcome. Recent efforts have revealed that the biology of HPV-related lesions in the cervix is strongly linked to the originally infected cell population. To address the hypothesis that topography also influences both gene expression profile and behaviour of anal (pre)neoplastic lesions, we correlated both proteomic signatures and clinicopathological features of tumours arising from two distinct portions of the anal canal: the lower part (squamous zone) and the more proximal anal transitional zone. Although microdissected cancer cells appeared indistinguishable by morphology (squamous phenotype), unsupervised clustering analysis of the whole proteome significantly highlighted the heterogeneity that exists within anal canal tumours. More importantly, two region-specific subtypes of SCC were revealed. The expression profile (sensitivity/specificity) of several selected biomarkers (keratin filaments) further confirmed the subclassification of anal (pre)cancers based on their cellular origin. Less commonly detected compared to their counterparts located in the squamous mucosa, SCCs originating in the transitional zone more frequently displayed a poor or basaloid differentiation, and were significantly correlated with reduced disease-free and overall survivals. Taken together, we present direct evidence that anal canal SCC comprises two distinct entities with different cells of origin, proteomic signatures, and survival rates. This study forms the basis for a dualistic classification of anal carcinoma

Root Canal Treatment of Mandibular Second Premolar with Three Separate Roots and Canals Using Spiral Computed Tomographic

PubMed Central

Hariharavel, V. P.; Kumar, A. Ashok; Ganesh, C.; Aravindhan, R.

2014-01-01

Anatomic and internal morphology of a root canal system is more complex and differs for each individual tooth of which mandibular premolars have earned the reputation for having aberrant anatomy. The occurrence of three canals with three separate foramina in mandibular second premolars is very rare. A wider knowledge on both clinical and radiological anatomy especially spiral computed tomographic is absolutely essential for the success of endodontic treatment. These teeth may require skillful and special root canal special shaping and obturating techniques. This paper reports an unusual case of a mandibular second premolar with atypical canal pattern that was successfully treated endodontically. PMID:25101187

Acceleration induced water removal from ear canals.

NASA Astrophysics Data System (ADS)

Kang, Hosung; Averett, Katelee; Jung, Sunghwan

2017-11-01

Children and adults commonly experience having water trapped in the ear canals after swimming. To remove the water, individuals will shake their head sideways. Since a child's ear canal has a smaller diameter, it requires more acceleration of the head to remove the trapped water. In this study, we theoretically and experimentally investigated the acceleration required to break the surface meniscus of the water in artificial ear canals and hydrophobic-coated glass tubes. In experiments, ear canal models were 3D-printed from a CT-scanned human head. Also, glass tubes were coated with silane to match the hydrophobicity in ear canals. Then, using a linear stage, we measured the acceleration values required to forcefully eject the water from the artificial ear canals and glass tubes. A theoretical model was developed to predict the critical acceleration at a given tube diameter and water volume by using a modified Rayleigh-Taylor instability. Furthermore, this research can shed light on the potential of long-term brain injury and damage by shaking the head to push the water out of the ear canal. This research was supported by National Science Foundation Grant CBET-1604424.

Apical and root canal space sealing abilities of resin and glass ionomer-based root canal obturation systems.

PubMed

Royer, Kinga; Liu, Xue Jun; Zhu, Qiang; Malmstrom, Hans; Ren, Yan-Fang

2013-01-01

To investigate the apical sealing ability of glass ionomer and resin-based root canal obturation systems in comparison to a conventional vertical compaction of warm guttapercha. Forty-five extracted human teeth were randomly assigned into 3 groups of 15 each: a resin-based (EndoRez), a glass ionomer-based (Activ GP), and a conventional gutta-percha plus pulp sealer obturation system (GP/EWT). Apical and root canal space sealing abilities were assessed on five cross-sections 1.0 mm apart starting from the apex. Cross-section images were analysed using a focus-variation 3D scanning microscope and unsealed space was calculated as the percentage of total root canal space occupied by voids and debris. EndoRez had significantly higher rate of apical leakage and deeper dye penetration as compared to GP/EWT and Activ GP. EndoRez group had also more voids and debris (22.5%) in the root canal spaces as compared to GP/EWT (10.5%) and Activ GP (10.8%). Apical leakages occurred not only along the root canal walls, but also along the gutta-percha cones with EndoRez as a result of significant polymerisation shrinkage of the resin sealer. Resin-based EndoRez did not form an adequate apical seal of filled root canals. Glass ionomer-based Activ GP was comparable to a vertical compaction of warm guttapercha plus EWT sealer in sealing root canal spaces.

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

PubMed

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.

Prevalence of and risk factors for anal human papillomavirus infection in men who have sex with women: a cross-national study.

PubMed

Nyitray, Alan G; Smith, Dan'elle; Villa, Luisa; Lazcano-Ponce, Eduardo; Abrahamsen, Martha; Papenfuss, Mary; Giuliano, Anna R

2010-05-15

Although the primary cause of anal cancer is human papillomavirus (HPV) infection in the anal canal, little attention has been paid to the epidemiology of anal HPV infection in men who have sex with women (MSW). Exfoliated cells from the anal canal of 902 MSW in Brazil (São Paulo), Mexico (Cuernavaca), and the United States (Tampa) were tested for HPV DNA. The prevalence of HPV infection in the anal canal (12.0%) was similar among MSW in each city (P=.77), whereas 7.0% had infection with oncogenic types. Men in Tampa had a 4-fold higher prevalence of infection with HPV type 16 (HPV-16) than that among men in São Paulo or Cuernavaca (P<.001). Duration of relationship with a primary sex partner and ever having oral or anal sex with a man was associated with infection with any HPV type and with any oncogenic type, whereas lifetime number of female sex partners was associated with infection with any HPV type. Anal canal HPV infection is commonly found among MSW, and the prevalence of infection with HPV-16 may differ substantially by geography. Men who have a larger lifetime number of female sex partners, who are in a sexual relationship of <1 year in duration, and who have a history of oral or anal sex with men were most likely to have an anal HPV infection.

Influence of operator experience on canal preparation time when using the rotary Ni-Ti ProFile system in simulated curved canals.

PubMed

Mesgouez, C; Rilliard, F; Matossian, L; Nassiri, K; Mandel, E

2003-03-01

The aim of this study was to determine the influence of operator experience on the time needed for canal preparation when using a rotary nickel-titanium (Ni-Ti) system. A total of 100 simulated curved canals in resin blocks were used. Four operators prepared a total of 25 canals each. The operators included practitioners with prior experience of the preparation technique, and practitioners with no experience. The working length for each instrument was precisely predetermined. All canals were instrumented with rotary Ni-Ti ProFile Variable Taper Series 29 engine-driven instruments using a high-torque handpiece (Maillefer, Ballaigues, Switzerland). The time taken to prepare each canal was recorded. Significant differences between the operators were analysed using the Student's t-test and the Kruskall-Wallis and Dunn nonparametric tests. Comparison of canal preparation times demonstrated a statistically significant difference between the four operators (P < 0.001). In the inexperienced group, a significant linear regression between canal number and preparation time occurred. Time required for canal preparation was inversely related to operator experience.

Planer orientation of the bilateral semicircular canals in dizzy patients.

PubMed

Aoki, Sachiko; Takei, Yasuhiko; Suzuki, Kazufumi; Masukawa, Ai; Arai, Yasuko

2012-10-01

Recent development of 3-dimensional analysis of eye movement enabled to detect the eye rotation axis, which is used to determine the responsible semicircular canal(s) in dizzy patients. Therefore, the knowledge of anatomical orientation of bilateral semicircular canals is essential, as all 6 canals influence the eye movements. Employing the new head coordinate system suitable for MR imaging, we calculated the angles of semicircular canal planes of both ears in 11 dizzy patients who had normal caloric response in both ears. The angles between adjacent canal pairs were nearly perpendicular in both ears. The angle between the posterior canal planes and head sagittal plane was 51° and significantly larger the angle between the anterior canal planes and head sagittal plane, which was 35°. The angle between the horizontal canal plane and head sagittal plane was almost orthogonal. Pairs of contralateral synergistic canal planes were not parallel, forming 10° between right and left horizontal canal planes, 17° between right anterior and left posterior canal planes and 19° between the right posterior and left anterior canal planes. Our measurement of the angles of adjacent canal pairs and the angle between each semicircular canal and head sagittal plane coincided with those of previous reports obtained from CT images and skull specimens. However, the angles between contralateral synergistic canal planes were more parallel than those of previous reports. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Antibacterial Activity of Diode Laser and Sodium Hypochlorite in Enterococcus Faecalis-Contaminated Root Canals.

PubMed

Sohrabi, Khosrow; Sooratgar, Aidin; Zolfagharnasab, Kaveh; Kharazifard, Mohammad Javad; Afkhami, Farzaneh

2016-01-01

The aim of the present in vitro study was to evaluate the disinfection ability of 980-nm diode laser in comparison with sodium hypochlorite (NaOCl) as a common root canal irrigant in canals infected with Enterococcus faecalis (E. faecalis). The root canals of 18 extracted single-rooted premolars were prepared by rotary system. After decoronation, the roots were autoclaved. One specimen was chosen for the negative control, and the remaining teeth were incubated with E. faecalis suspension for two weeks. Subsequently, one specimen was selected as the positive control and the remaining samples were divided into two groups (n=8). The samples of the first group were irrigated with 5.25% NaOCl and the second group were treated with a 980-nm diode laser. Microbial samples were taken from the root canals and bacterial cultivation was carried out. The average value and the standard deviation of colony-forming units (CFU) of each specimen were measured using descriptive statistics. The student's t-test was used to compare the reduction in CFU in each group. The equality of variance of CFU was measured by the Levene's test. NaOCl resulted in 99.87% removal of the bacteria and showed significantly more antibacterial effect compared to the 980-nm diode laser which led to 96.56% bacterial reduction (P<0.05). Although 5.25% NaOCl seems to reduce E. faecalis more effectively, the diode laser also reduced the bacterial count. Therefore a 980-nm diode laser could be considered as a complementary disinfection method in root canal treatment.

21 CFR 872.3810 - Root canal post.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Root canal post. 872.3810 Section 872.3810 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3810 Root canal post. (a) Identification. A root canal...

Clinical significance of dental root canal microflora.

PubMed

Gomes, B P; Lilley, J D; Drucker, D B

1996-01-01

Previous work by this group has shown that a significant association exists between pain and the presence of either Prevotella or Peptostreptococcus spp. in dental root canals. The aim of this study was to examine a more extensive series of canals microbiologically, to determine whether any other particular endodontic symptoms or clinical signs showed specific associations with individual bacterial species. Seventy root canals were examined microbiologically and clinical data collected to investigate in detail such associations. Of the canals studied, 37 were associated with pain, 49 with tenderness to percussion, 23 with swelling, six with purulent exudate and 57 presented with wet root canals. Anaerobes were isolated from 70.3% of painful canals and from 29.7% of pain-free canals. Significant associations were found between (a) pain and either Prevotella spp. or peptostreptococci, both with P < 0.01; (b) tenderness to percussion and Prevotella spp. (P < 0.01) or anaerobes (P < 0.05); (c) swelling and Eubacterium spp. (P < 0.01), or with Prevotella spp. or Pstr. micros, both with P < 0.05; (d) purulent exudate and any one of F. necrophorum (P < 0.01), Prev. loescheii, Streptoccoccus constellatus or Bacteroides spp. (each P < 0.05); (e) wet canal and facultative anaerobes (P < 0.01), and any one of the genera of Eubacterium, Peptostreptococcus, Prevotella or Propionibacterium (each P < 0.05). It was concluded that several different endodontic clinical signs and symptoms are significantly associated with specific bacterial species.

Retromolar foramen and canal: a comprehensive review on its anatomy and clinical applications.

PubMed

Kumar Potu, B; Jagadeesan, S; Bhat, K M R; Rao Sirasanagandla, S

2013-06-01

The retromolar foramen (RMF) and retromolar canal (RMC) are the anatomical structures of the mandible located in retromolar fossa behind the third molar tooth. This foramen and canal contain neurovascular structures which provide accessory/additional innervation to the mandibular molars and the buccal area. These neurovascular contents of the canal gain more importance in medical and dental practice, because these elements are vulnerable to damage during placement of osteointegrated implants, endodontic treatment and sagittal split osteotomy surgeries and a detailed knowledge of this anatomical variation would be vital in understanding failed inferior alveolar nerve blockage, spread of infection and also metastasis. Although few studies have been conducted in the past showing the incidence and types in different population groups, a lacunae in comprehensive review of this structure is lacking. Though this variation posed challenging situations for the practicing surgeons, it has been quite neglected and the incidence of it is not well presented in all the textbooks. Hence, we made an attempt to provide a consolidated review regarding variations and clinical applications of the RMF and RMC. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

Maxillary first molar with five canals

PubMed Central

Umer, Fahad

2014-01-01

Root canal treatment is a technically demanding procedure especially in the case of maxillary first molar where the anatomy is extremely variable. Failure to recognise and treat these variations may lead to unpredictable outcomes. This case report describes non-surgical endodontic treatment of a maxillary first molar with two palatal and two mesiobuccal canals. It also highlights the need for good anatomical knowledge of root canal morphology and its variations in order to achieve consistently successful results. PMID:25239993

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

DTIC Science & Technology

2016-06-13

unless the clinician is careful to identify it. Missing this canal can contribute to a sequelae of persistent disease that may require the retreatment of...likelihood of finding MM canals. This is likely due to the fact that root canal retreatments are done on an older patient at a higher rate in the...canal. However, missing a canal can lead to continued pain and discomfort to the patient and other sequelae that may require nonsurgical retreatment

Photodynamic treatment of endodontic polymicrobial infection in vitro

PubMed Central

Fimple, Jacob Lee; Fontana, Carla Raquel; Foschi, Federico; Ruggiero, Karriann; Song, Xiaoqing; Pagonis, Tom C.; Tanner, Anne C. R.; Kent, Ralph; Doukas, Apostolos G.; Stashenko, Philip P.; Soukos, Nikolaos S.

2008-01-01

We investigated the photodynamic effects of methylene blue (MB) on multi-species root canal biofilms comprising Actinomyces israelii, Fusobacterium nucleatum subspecies nucleatum, Porphyromonas gingivalis and Prevotella intermedia in experimentally infected root canals of extracted human teeth in vitro. The four test microorganisms were detected in root canals using DNA probes. Scanning electron microscopy (SEM) showed the presence of biofilms in root canals prior to therapy. Root canal systems were incubated with MB (25 µg/ml) for 10 minutes followed by exposure to red light at 665 nm with an energy fluence of 30 J/cm2. Light was delivered from a diode laser via a 250 µm diameter polymethyl methacrylate optical fiber that uniformly distributed light at 360°. Photodynamic therapy (PDT) achieved up to 80% reduction of colony-forming unit counts. We conclude that PDT can be an effective adjunct to standard endodontic antimicrobial treatment when the PDT parameters are optimized. PMID:18498901

Inverse solution of ear-canal area function from reflectance

PubMed Central

Rasetshwane, Daniel M.; Neely, Stephen T.

2011-01-01

A number of acoustical applications require the transformation of acoustical quantities, such as impedance and pressure that are measured at the entrance of the ear canal, to quantities at the eardrum. This transformation often requires knowledge of the shape of the ear canal. Previous attempts to measure ear-canal area functions were either invasive, non-reproducible, or could only measure the area function up to a point mid-way along the canal. A method to determine the area function of the ear canal from measurements of acoustic impedance at the entrance of the ear canal is described. The method is based on a solution to the inverse problem in which measurements of impedance are used to calculate reflectance, which is then used to determine the area function of the canal. The mean ear-canal area function determined using this method is similar to mean ear-canal area functions measured by other researchers using different techniques. The advantage of the proposed method over previous methods is that it is non- invasive, fast, and reproducible. PMID:22225043

Experimental selective posterior semicircular canal laser deafferentation.

PubMed

Naguib, Maged B

2005-05-01

In this experimental study, we attempted to perform selective deafferentation of the posterior semicircular canal ampulla of guinea pigs using carbon dioxide laser beam. The results of this study document the efficacy of this procedure in achieving deafferentation of the posterior semicircular canal safely with regards to the other semicircular canals, the otolithic organ and the organ of hearing. Moreover, the procedure is performed with relative ease compared with other procedures previously described for selective deafferentation of the posterior semicircular canal. The clinical application of such a procedure for the treatment of intractable benign paroxysmal positional vertigo in humans is suggested.

Spatial orientation of semicircular canals and afferent sensitivity vectors in pigeons

NASA Technical Reports Server (NTRS)

Dickman, J. D.

1996-01-01

Rotational head motion in vertebrates is detected by the semicircular canal system, whose innervating primary afferent fibers carry information about movement in specific head planes. The semicircular canals have been qualitatively examined over a number of years, and the canal planes have been quantitatively characterized in several animal species. The present study first determined the geometric relationship between individual semicircular canals and between the canals and the stereotactic head planes in pigeons. Stereotactic measurements of multiple points along the circumference of the bony canals were taken, and the measured points fitted with a three-dimensional planar surface. Direction normals to the plane's surface were calculated and used to define angles between semicircular canal pairs. Because of the unusual shape of the anterior semicircular canals in pigeons, two planes, a major and a minor, were fitted to the canal's course. Calculated angle values for all canals indicated that the horizontal and posterior semicircular canals are nearly orthogonal, but the anterior canals have substantial deviations from orthogonality with other canal planes. Next, the responses of the afferent fibers that innervate each of the semicircular canals to 0.5 Hz sinusoidal rotation about an earth-vertical axis were obtained. The head orientation relative to the rotation axis was systematically varied so that directions of maximum sensitivity for each canal afferent could be determined. These sensitivity vectors were then compared with the canal plane direction normals. The afferents that innervated specific semicircular canals formed homogeneous clusters of sensitivity vectors in different head planes. The horizontal and posterior afferents had average sensitivity vectors that were largely co-incident with the innervated canal plane direction normals. Anterior canal afferents, however, appeared to synthesize contributions from the major and minor plane components of the

7. View north at back (canal side) of culvert inlet, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

7. View north at back (canal side) of culvert inlet, with canal bank completely removed. Background to foreground: back of inlet headwall with tops of high inlet barrels exposed; vertical transition wall between high inlet barrels and low, interior, inlet barrels; tops of low interior barrels; vertical heartening planks and low cutoff wall at site of former canal edge of canal bank; dewatered canal bed and plank sheathing on top of culvert barrels beneath canal bed. - Delaware & Raritan Canal, Ten Mile Run Culvert, 1.5 miles South of Blackwells Road, East Millstone, Somerset County, NJ

Prevalence of and Risk Factors for Anal Oncogenic Human Papillomavirus Infection Among HIV-Infected Women in France in the Combination Antiretroviral Therapy Era.

PubMed

Heard, Isabelle; Poizot-Martin, Isabelle; Potard, Valérie; Etienney, Isabelle; Crenn-Hebert, Catherine; Moore, Catherine; Touraine, Philippe; Cubie, Heather; Costagliola, Dominique

2016-05-01

Little is known about the type-specific prevalence of anal human papillomavirus (HPV) infection and risk factors for anal high-risk (HR) HPV infection in human immunodeficiency virus (HIV)-infected women. A cross-sectional study of anal and cervical HPV infection was nested within a gynecological cohort of HIV-infected women. Specimens were tested for type-specific DNA using a polymerase chain reaction-based assay. The study population consisted of 311 women with a median age of 45.3 years, of whom 42.8% originated from sub-Saharan Africa and 96.8% were receiving combination antiretroviral therapy. The median CD4(+)cell count was 612/μL, and the HIV load was <50 copies/mL in 84.1%. HR-HPV types were detected in the anal canal in 148 women (47.6%) and in the cervix in 82 (26.4%). HPV-16 was the most prevalent type in both the anal canal (13.2% of women) and the cervix (5.1%). In multivariable analysis, factors associated with prevalent anal HR-HPV infection were CD4(+)count <350/μL (odds ratio, 2.9; 95% confidence interval, 1.3-6.5), concurrent cervical lesions (2.6; 1.0-4.3), and cervical HR-HPV infection (1.8; 1.0-3.2). The high prevalence of HR-HPV types, including HPV-16, in the anal canal of HIV-positive women is concerning. Anal cancer screening should be considered for HIV-positive women as part of their routine care. © The Author 2015. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

New bacterial composition in primary and persistent/secondary endodontic infections with respect to clinical and radiographic findings.

PubMed

Tennert, Christian; Fuhrmann, Maximilian; Wittmer, Annette; Karygianni, Lamprini; Altenburger, Markus J; Pelz, Klaus; Hellwig, Elmar; Al-Ahmad, Ali

2014-05-01

The aim of the present study was to analyze the microbiota of primary and secondary/persistent endodontic infections of patients undergoing endodontic treatment with respect to clinical and radiographic findings. Samples from the root canals of 21 German patients were taken using 3 sequential sterile paper points. In the case of a root canal filling, gutta-percha was removed with sterile files, and samples were taken using sterile paper points. The samples were plated, and microorganisms were then isolated and identified morphologically by biochemical analysis and sequencing the 16S rRNA genes of isolated microorganisms. In 12 of 21 root canals, 33 different species could be isolated. Six (50%) of the cases with isolated microorganisms were primary, and 6 (50%) cases were endodontic infections associated with root-filled teeth. Twelve of the isolated species were facultative anaerobic and 21 obligate anaerobic. Monomicrobial infections were found for Enterococcus faecalis and Actinomyces viscosus. E. faecalis was most frequently isolated in secondary endodontic infections (33%). Moraxella osloensis was isolated from a secondary endodontic infection that had an insufficient root canal filling accompanied by a mild sensation of pain. A new bacterial composition compromising Atopobium rimae, Anaerococcus prevotii, Pseudoramibacter alactolyticus, Dialister invisus, and Fusobacterium nucleatum was recovered from teeth with chronic apical abscesses. New bacterial combinations were found and correlated to clinical and radiographic findings, particularly to chronic apical abscesses. M. osloensis was detected in root canals for the second time and only in German patients. Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

A randomized, blinded study of canal wall up versus canal wall down mastoidectomy determining the differences in viewing middle ear anatomy and pathology.

PubMed

Hulka, G F; McElveen, J T

1998-09-01

Canal wall down and intact canal wall tympanomastoidectomy represent two surgical approaches to middle ear pathology. The authors hypothesize that there is a difference in the ability to view structures in the middle ear between these two methods. Depending on the individual, many surgeons have used the two different techniques of intact canal wall and canal wall down tympanomastoidectomy for approaching the middle ear. However, opinions conflict as to which approach provides the best visualization of different locations in the middle ear. This study prospectively evaluated temporal bones to determine the differences in visualizing structures of the middle ear using these two approaches. Twelve temporal bones underwent a standardized canal wall down tympanomastoidectomy using a reversible canal wall down technique. All bones were viewed in two dissections: intact canal wall and canal wall down preparations. Four points previously had been marked on each temporal bone in randomly assigned colors. These points include the sinus tympani, posterior crus of stapes, lateral epitympanum, and the Eustachian tube orifice. An observer blinded to the purpose of the study, color, and number of locations recorded the color and location of marks observed within the temporal bones. Randomized bones of two separate settings were viewed such that each bone was viewed in both the canal wall down and the intact canal wall preparations. A significant difference was noted in the ability to observe middle ear pathology between the intact canal wall versus canal wall down tympanomastoidectomy, with the latter showing superiority (p < 0.001). Of the four subsites, the sinus tympani, posterior crus of stapes, and lateral epitympanum were observed more frequently with the canal wall down. There was no significant difference in the ability to observe the Eustachian tube orifice between the two techniques. Statistical analysis shows good reproducibility and randomization of this study. The

Root canal revascularization. The beginning of a new era in endodontics.

PubMed

Alrahabi, Mothanna K; Ali, Mahmoud M

2014-05-01

Endodontic management of immature anterior teeth with necrotic pulps is a great challenge. Although there are different treatment procedures to deal with this problem such as apexification by using calcium hydroxide dressings or applying a barrier of mineral trioxide aggregate and gutta-percha obturation, the outcomes are still unsatisfactory and the root might still be weak. Recently, a new treatment protocol by revascularization of immature non-vital, infected teeth was introduced to regenerate dental structure and complete the root maturation. However, larger case series with longer follow-up periods are required to accept revascularization as the standard protocol for management of immature non-vital, infected teeth. In this review, we discuss the concept of root canal revascularization, revascularization mechanisms, and the structure of the regenerated tissues.

160. Photocopy of drawing (taken from Twin Falls Canal Company ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

160. Photocopy of drawing (taken from Twin Falls Canal Company Field Book #361 #86, page 1). SCALE DRAWING, CANAL HEADGATES AND CANAL SURVEY, 'A' LINE. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

The role of rice fields, fish ponds and water canals for transmission of fish-borne zoonotic trematodes in aquaculture ponds in Nam Dinh Province, Vietnam.

PubMed

Madsen, Henry; Dung, Bui Thi; The, Dang Tat; Viet, Nguyen Khue; Dalsgaard, Anders; Van, Phan Thi

2015-12-08

Fish-borne zoonotic trematodes (FZT), such as Clonorchis sinensis, Opistorchis viverini (Opisthorchiidae) and intestinal trematodes of the family Heterophyidae, constitute a public health hazard in Vietnam and infections with these trematodes has been linked to consumption of raw or undercooked fish from aquaculture. The FZT transmission pathways, however, are more complicated than just the presence of intermediate snail hosts in aquaculture ponds as ponds may exchange water with surrounding habitats such as rice fields and irrigation canals and thereby these surrounding habitats may be a source of snails and cercariae and contribute to FZT infection in cultured fish. This is a longitudinal descriptive study on selected farms (n = 30) in Nam Dinh Province which is endemic for FZT. At each farm, we sampled one pond, a small irrigation canal used to supply the pond with water, and a nearby rice field. At each of these three sites, we estimated the density of the FZT intermediate snail hosts and determined their trematode infection status. Comparative analysis was performed for the prevalence and density of FZT infections in fish and snails. Species of the Thiaridae, and most notably Melanoides tuberculata, the most important host species for FZT belonging to the Heterophyidae, were particularly abundant in ponds and small canals, i.e. M. tuberculata was found in 27 ponds and 13 small canals. Bithynia fuchsiana, a potential host for both Heterophyidae and Opisthorchiidae, was rarely found in fish ponds but common in rice fields. A total of 12 types of cercariae were found in the snails and pleurolophocercous cercariae, primarily FZT, constituted about 40 % of all cercarial infections. The fish species cultured were mainly carp species and Haplorchis pumilio was the dominating trematode species infecting fish. Clonorchis spp. were not recorded in any of the ponds. FZT transmission to fish was intense during the summer period (May-June to November) but less intense

Anatomical and morphological study of the subcoracoacromial canal.

PubMed

Le Reun, O; Lebhar, J; Mateos, F; Voisin, J L; Thomazeau, H; Ropars, M

2016-12-01

Many clinical anatomy studies have looked into how variations in the acromion, coracoacromial ligament (CAL) and subacromial space are associated with rotator cuff injuries. However, no study up to now had defined anatomically the fibro-osseous canal that confines the supraspinatus muscle in the subcoracoacromial space. Through an anatomical study of the scapula, we defined the bone-related parameters of this canal and its anatomical variations. This study on dry bones involved 71 scapulas. With standardised photographs in two orthogonal views (superior and lateral), the surface area of the subcoracoacromial canal and the anatomical parameters making up this canal were defined and measured using image analysis software. The primary analysis evaluated the anatomical parameters of the canal as a function of three canal surface area groups; the secondary analysis looked into how variations in the canal surface area were related to the type of acromion according to the Bigliani classification. Relative to glenoid width, the group with a large canal surface area (L) had significantly less lateral overhang of the acromion than the group with a small canal surface area (S), with ratios of 0.41±0.23 and 0.58±0.3, respectively (P=0.04). The mean length of the CAL was 46±8mm in the L group and 39±9mm in the S group (P=0.003). The coracoacromial arch angle was 38°±11° in the L group and 34°±9° in the S group; the canal surface area was smaller in specimens with a smaller coracoacromial arch angle (P=0.20). Apart from acromial morphology, there could be innate anatomical features of the scapula that predispose people to extrinsic lesions to the supraspinatus tendon (lateral overhang, coracoacromial arch angle) by reducing the subcoracoacromial canal's surface area. Anatomical descriptive study. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Endodontic management of middle mesial canal of the mandibular molar

PubMed Central

Sundaresh, K J; Srinivasan, Raghu; Mallikarjuna, Rachappa; Rajalbandi, Sandeep

2013-01-01

Thorough knowledge of root canal morphology and unusual anatomy of the tooth is critical for successful endodontic treatment. Although the most common configuration is two roots and three root canals, mandibular molars might have many different combinations. In the literature, it is less described about three mesial canals and two distal canals in mandibular second molars, indicating a rare anatomical configuration. A case of unusual root canal morphology is presented to demonstrate anatomical variations in mandibular molars. Endodontic therapy was performed in a mandibular second molar with five separate canals, three mesial and two distal. This report points out the importance of looking for additional canals and unusual canal morphology, because knowledge of their existence might occasionally enable clinicians to treat a case successfully that otherwise might have ended in failure. In conclusion, every attempt should be made to find and treat all root canals of a tooth. PMID:23349182

Mandibular molar with five root canals.

PubMed

Barletta, Fernando Branco; Dotto, Sidney Ricardo; Reis, Magda de Sousa; Ferreira, Ronise; Travassos, Rosana Maria Coelho

2008-12-01

The purpose of this study was to demonstrate the importance of knowledge of the internal anatomy of root canals for the success of endodontic treatment. Lack of knowledge of anatomic variations and their characteristics in different teeth has been pointed out as one of the main causes of endodontic therapy failure. In this report, the authors describe the endodontic treatment of a mandibular first molar with five root canals, evaluate the rate of occurrence of this number of canals, and discuss the importance of their identification and treatment.

Microbial Ecosystem Analysis in Root Canal Infections Refractory to Endodontic Treatment.

PubMed

Henriques, Luiz Carlos Feitosa; de Brito, Luciana Carla Neves; Tavares, Warley Luciano Faria; Teles, Ricardo Palmier; Vieira, Leda Quércia; Teles, Flávia Rodrigues; Sobrinho, Antônio Paulino Ribeiro

2016-08-01

The purpose of this study was to combine multiple displacement amplification and checkerboard DNA-DNA hybridization to qualitatively and quantitatively evaluate the microbiota present in infections refractory to endodontic treatment. The subjects of this study were 40 patients presenting with periapical lesions refractory to endodontic treatment. Samples were taken by scraping or filing root canal walls with a #10 K-type hand file. Sample DNA was amplified by multiple displacement amplification, and the levels of 107 bacterial taxa were analyzed by checkerboard DNA-DNA hybridization. The taxa were divided into 3 distinct microbial populations depending on their mean proportion in samples (% DNA probe counts ± standard error of the mean) as follows: dominant (≥3.0%), subdominant (>1.6%-3.0%), and residual (≤1.6%) populations. The significance of differences was determined using the Mann-Whitney test. The taxa present with the highest mean proportions (constituting the dominant population) were Corynebacterium diphtheriae (8.03 ± 0.98), Porphyromonas gingivalis (5.42 ± 2.09), Streptococcus sobrinus (5.33 ± 0.69), and Stenotrophomonas maltophilia (4.72 ± 1.73). Among the subdominant population were Eubacterium saphenum (3.85 ± 1.06), Helicobacter pylori (3.16 ± 0.62), Dialister pneumosintes (3.12 ± 1.1), Clostridium difficile (2.74 ± 0.41), Enterobacter agglomerans (2.64 ± 0.54), Salmonella enterica (2.51 ± 0.52), Mobiluncus mulieris (2.44 ± 0.6), and Klebsiella oxytoca (2.32 ± 0.66). In the population of bacteria present at the lowest mean proportions (the residual population), Bacteroides ureolyticus (0.04 ± 0.01), Haemophilus influenzae (0.04 ± 0.02), and Prevotella oris (0.01 ± 0.01) were found at the lowest mean proportions. Enterococcus faecalis was detected in the residual population (0.52 ± 0.26). The microbial climax community in teeth refractory to endodontic treatment not only harbors medically

179. Photocopy of Photograph, Twin Falls Canal Company, Bisbee Photo, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

179. Photocopy of Photograph, Twin Falls Canal Company, Bisbee Photo, September, 1912. Photographer unknown. VIEW OF LOW LINE CANAL, TWIN FALLS COUNTY; VIEW OF LOW LINE CANAL IN PETE LINK'S FIELD. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

Influence of a glide path on apical extrusion of debris during canal preparation using single-file systems in curved canals.

PubMed

Topçuoğlu, H S; Düzgün, S; Akpek, F; Topçuoğlu, G; Aktı, A

2016-06-01

To evaluate the effect of a glide path on the amount of apically extruded debris during canal preparation using single-file systems in curved canals. Ninety extracted mandibular molar teeth were randomly assigned to six groups (n = 15 for each group) for canal instrumentation. Endodontic access cavities were prepared in each tooth. In three of the six groups, a glide path was not created whereas a glide path was created using PathFile instruments on the mesial canals of all teeth in the remaining three groups. The mesial canals of the teeth were then instrumented with the following single-file instrument systems: WaveOne, Reciproc and OneShape. Debris extruded apically during instrumentation was collected into pre-weighed Eppendorf tubes. The tubes were then stored in an incubator at 70 °C for 5 days. The weight of the dry extruded debris was established by subtracting the pre-instrumentation and post-instrumentation weight of the Eppendorf tubes for each group. The data obtained were analysed using one-way analysis of variance (anova) and Tukey's post hoc tests. The OneShape file was associated with less debris extrusion than the Reciproc and WaveOne files when canal instrumentation was performed without a glide path (P < 0.05). However, no significant difference was found between the Reciproc and WaveOne files (P > 0.05). There was no significant difference amongst the OneShape, Reciproc and WaveOne files when a glide path was created before canal preparation in curved root canals (P > 0.05). All systems extruded significantly less debris in groups with a glide path than in groups without a glide path (P < 0.05). All instruments were associated with apical extrusion of debris. Creating a glide path prior to canal instrumentation reduced the amount of apically extruded debris in curved canals. © 2015 International Endodontic Journal. Published by John Wiley & Sons Ltd.

Gender and laterality in semicircular canal dehiscence syndrome.

PubMed

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.

Association of black-pigmented bacteria with endodontic infections.

PubMed

Baumgartner, J C; Watkins, B J; Bae, K S; Xia, T

1999-06-01

Black-pigmented bacteria (BPB) have been associated with endodontic infections. The purpose of this study was to evaluate further the presence of BPB with the clinical signs and symptoms associated with endodontic infections. Microbial samples were collected from the root canals of 40 intact teeth with necrotic pulps and apical periodontitis. Conventional laboratory methods were used for identification of the strains of BPB isolated in pure culture. In addition, the polymerase chain reaction and specific primers for 16S r-RNA genes were used to differentiate Prevotella nigrescens from Prevotella intermedia. Twenty-two (55%) samples were positive for the growth of BPB. Of those, 11 of 22 (50%) were identified as P. nigrescens, 8 of 22 (36%) were P. intermedia, 2 of 22 (9%) were Porphyromonas gingivalis, and 1 of 22 (5%) was Prevotella melaninogenica. Sixteen of the 22 root canals positive for the growth of BPB were associated with purulent drainage either from the root canal or an associated sinus tract. Statistical analysis did not show a significant relationship for the presence of BPB with clinical signs and symptoms.

Matters of simulation of the semicircular canal system

NASA Technical Reports Server (NTRS)

Gurfinkel, V. S.; Petukhov, S. V.

1977-01-01

A scale model of the human semicircular canal system was developed based on the theory of dynamic similitude. This enlarged model makes it convenient to conduct tests on the vestibular processes and dynamics in the semicircular canals. Tests revealed hydromechanical interaction between canals, with asymmetry of the conditions of movement of the endolymph in the canals in opposite directions. A type of vestibular reactions, occurring with angular oscillations of the head, was predicted and demonstrated using this model and human test subjects.

The failures of root canal preparation with hand ProTaper.

PubMed

Bătăiosu, Marilena; Diaconu, Oana; Moraru, Iren; Dăguci, C; Tuculină, Mihaela; Dăguci, Luminiţa; Gheorghiţă, Lelia

2012-07-01

The failures of root canal preparation are due to some anatomical deviation (canal in "C" or "S") and some technique errors. The technique errors are usually present in canal root cleansing and shaping stage and are the result of endodontic treatment objectives deviation. Our study was made on technique errors while preparing the canal roots with hand ProTaper. Our study was made "in vitro" on 84 extracted teeth (molars, premolars, incisors and canines). The canal root of these teeth were cleansed and shaped with hand ProTaper by crown-down technique and canal irrigation with NaOCl(2,5%). The dental preparation control was made by X-ray. During canal root preparation some failures were observed like: canal root overinstrumentation, zipping and stripping phenomenon, discarded and/or fractured instruments. Hand ProTaper represents a revolutionary progress of endodontic treatment, but a deviation from accepted rules of canal root instrumentation can lead to failures of endodontic treatment.

The failures of root canal preparation with hand ProTaper

PubMed Central

Bătăiosu, Marilena; Diaconu, Oana; Moraru, Iren; Dăguci, C.; Ţuculină, Mihaela; Dăguci, Luminiţa; Gheorghiţă, Lelia

2012-01-01

The failures of root canal preparation are due to some anatomical deviation (canal in “C” or “S”) and some technique errors. The technique errors are usually present in canal root cleansing and shaping stage and are the result of endodontic treatment objectives deviation. Objectives: Our study was made on technique errors while preparing the canal roots with hand ProTaper. Methodology: Our study was made “in vitro” on 84 extracted teeth (molars, premolars, incisors and canines). The canal root of these teeth were cleansed and shaped with hand ProTaper by crown-down technique and canal irrigation with NaOCl(2,5%). The dental preparation control was made by X-ray. Results: During canal root preparation some failures were observed like: canal root overinstrumentation, zipping and stripping phenomenon, discarded and/or fractured instruments. Conclusions: Hand ProTaper represents a revolutionary progress of endodontic treatment, but a deviation from accepted rules of canal root instrumentation can lead to failures of endodontic treatment. PMID:24778848

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

PubMed

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 < .05). The differences in the distribution of MM canals based on sex, ethnicity, 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.

Frequency, microbial interactions, and antimicrobial susceptibility of Fusobacterium nucleatum and Fusobacterium necrophorum isolated from primary endodontic infections.

PubMed

Jacinto, Rogério C; Montagner, Francisco; Signoretti, Fernanda G C; Almeida, Geovania C; Gomes, Brenda P F A

2008-12-01

This study assessed the prevalence and microbial interactions of Fusobacterium nucleatum and Fusobacterium necrophorum in primary endodontic infections from a Brazilian population and their antimicrobial susceptibility to some antibiotics by the E-test. One hundred ten samples from infected teeth with periapical pathologies were analyzed by culture methods. Five hundred eighty individual strains were isolated; 81.4% were strict anaerobes. F. nucleatum was found in 38 root canals and was associated with Porphyromonas gingivalis, Prevotella spp., and Eubacterium spp. F. necrophorum was found in 20 root canals and was associated with Peptostreptococcus prevotii. The simultaneous presence of F. nucleatum and F. necrophorum was not related to endodontic symptoms (p > 0.05). They were 100% susceptible to amoxicillin, amoxicillin/clavulanate, and cephaclor. Fusobacterium spp. is frequently isolated from primary-infected root canals of teeth with periapical pathologies. Amoxicillin is a useful antibiotic against F. nucleatum and F. necrophorum in endodontic infections and has been prescribed as the first choice in Brazil.

Mechanized instrumentation of root canals oscillating systems.

PubMed

Leonardo, Renato de Toledo; Puente, Carlos Garcia; Jaime, Alejandro; Jent, Carol

2013-01-01

Cleaning and shaping are important steps in the root canal treatment. Despite the technological advances in endodontics, K and Hedstroen files are still widely used. In an attempt to be more effective in preparing the root canals, faster and more cutting efficient kinematic, alloys and design alternatives utilizing mechanically oscillating or rotary files are proposed. Even with all these technological innovating alternatives, the preparation of root canals remains a challenge.

Ship canals and aquatic ecosystems

USGS Publications Warehouse

Aron, William I.; Smith, Stanford H.

1971-01-01

Through a combination of ecosystem homeostasis and the perversity of man and nature, oftentimes the significant biological changes effected by environmental modifications are not detected until long after the initial change has taken place. The immediate impact, which may range from the spectacular to the undetectable, is a deceptive measure of the long-term and often more important changes in the ecosystem. Two major engineering achievements illustrate this premise: (i) construction of the Erie Canal, which provided access from the Atlantic Ocean to the Great Lakes, and the Welland Canal, which bypasses the block between Lakes Ontario and Erie created by Niagara Falls (Fig. 1), and (ii) construction of the Suez Canal between the Red Sea and the Mediterranean Sea.

Er:YAG laser: antimicrobial effects in the root canals of dogs' teeth with pulp necrosis and chronic periapical lesions.

PubMed

Leonardo, Mário R; Guillén-Carías, M G; Pécora, J D; Ito, I Y; Silva, L A B

2005-06-01

Our goal in this study was to evaluate the antimicrobial effect of Er:YAG laser applied after biomechanical preparation of the root canals of dog's teeth with apical periodontitis. Various in vitro studies have reported effective bacterial reduction in infected root canals using Er:YAG laser. However, there is no in vivo research to support these results. Forty root canals of dogs' premolar teeth with pulp necrosis and chronic periapical lesions were used. An initial microbiological sample was taken, and after biomechanical preparation was carried out, a second microbiological sample was taken. The teeth were divided into two groups: Group I-biomechanical preparation was taken of root canals without Er:YAG laser application; Group II-biomechanical preparation was taken of root canals with Er:YAG laser application using 140-mJ input, 63-mJ output/15 Hz. After coronal sealing, the root canals were left empty for 7 days at which time a third microbiological sample was taken. The collected material was removed from the root canal with a #40 K file and placed in transport media. It was serially diluted and seeded on culture dishes selective for anaerobes, aerobes, and total streptococci. Colony-forming units per milliliter (CFU/mL) were counted. Groups I and II showed an increase of CFU/mL for all microorganisms 7 days after treatment, being statistically significant for anaerobes in Group I and for anaerobes and total streptococci in Group II. When comparing CFU/mL of Groups I and II, there was a statistically significant increase after 7 d for total streptococci in Group II. Er:YAG laser applied after biomechanical preparation did not reduce microorganisms in the root canal system.

Sodium hypochlorite chemical burn in an endodontist's eye during canal treatment using operating microscope.

PubMed

Regalado Farreras, Desirée C; Puente, Carlos García; Estrela, Carlos

2014-08-01

This study describes a case of eye burn induced by sodium hypochlorite used as an irrigant during root canal preparation. A 24-year-old female endodontist was using an operating microscope during root canal treatment, and as the root canal was irrigated, the pressure cannula burst and the irrigant (3.5% sodium hypochlorite) came into direct contact with her left eye. She immediately sought ophthalmologic emergency care for pain, redness of the cornea, burning sensation, photophobia, intraocular pressure, and blurred vision. The initial treatment consisted of washing the eye with saline solution and administering analgesic and anti-inflammatory (steroid) medications. One day after the accident, a topical demulcent and hydroxypropyl medication were applied to the eyeball (conjunctiva), the eye was bandaged for 24 hours, and rest was prescribed for 7 days. Eight days later, a corneal ulcer was diagnosed, and antibiotic and anti-inflammatory (steroid) medications were used. Vision was restored without any sequelae 4 weeks after the accident. The endodontist was instructed to apply control medication (Lagricel; Sophia SA, Caracas, Venezuela) for 3 months and to return for ophthalmologic follow-up every 6 months. Sodium hypochlorite is an effective antibacterial irrigant indicated for the treatment of root canal infections. The tissue cytotoxicity highlights the need to inform the patient of the risk factors of accidents and enhance care with individual protection equipment for the patient and the professional during clinical procedures. Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Mandibular first and second molars with three mesial canals: a case series

PubMed Central

Aminsobhani, Mohsen; Bolhari, Behnam; Shokouhinejad, Noushin; Ghorbanzadeh, Abdollah; Ghabraei, Sholeh; Rahmani, Mohamad Bagher

2010-01-01

Adequate cleaning, shaping and filling of the root canal system are mandatory for successful root canal treatment. Thorough knowledge of root canal morphology and unusual anatomy of the tooth is critical for the practitioner. The occurrence and location of the third mesial canal (Middle Mesial Canal) in mandibular first and second molars in relation to other two mesial canals that were treated in private practice were studied. In 27 clinical cases, the presence of a middle mesial canal was demonstrated. The third canal was located in the middle of the distance between the mesiobuccal and mesiolingual canals. This canal configuration was found in six second lower molars and twenty one first molars. Middle mesial canal in all of our cases joined to mesiobuccal or mesiolingual canals. None of the teeth consisted of three independent canals with three apical foramina. In conclusion, every attempt should be made to find and treat all root canals of a tooth. PMID:24778681

[Group B streptococcus meningitis and infection surrounding the spinal canal caused by bacterial transmission from rectal ulcer via Batson's plexus].

PubMed

Tsutsumi, Ryosuke; Saito, Masaaki; Yoshizawa, Toshihiro

2011-07-01

A 62-year-old man was admitted to our hospital because of fever and disturbed consciousness. He suffered from persistent constipation due to diabetic autonomic neuropathy. On admission, neck stiffness and weakness of the lower extremities were observed. Cerebrospinal fluid (CSF) pleocytosis and decreased CSF glucose concentration showed the presence of meningitis. Bacterial culture of CSF was negative. One week after admission, he suddenly suffered from massive bleeding from the rectum, where a hemorrhagic ulcer caused by severe persistent constipation was observed. Contrast-enhanced CT scans and gadolinium-enhanced MR scans demonstrated a lumbar spinal epidural abscess, paraspinal muscle abscess, and cervical osteomyelitis. Streptococcus agalactiae, a bacterial species belonging to the group B streptococci, was isolated from pus obtained by needle puncture of the paraspinal muscle abscess. His entire condition was treated successfully with ampicillin and cefotaxime. Group B streptococci normally colonize the mucous membrane of the genital or lower gastrointestinal regions and rarely cause a spinal epidural abscess. However, in this case, the existence of a rectal ulcer probably made it possible for S. agalactiae to cause an infection of the epidural space or paraspinal muscles via the spinal valveless venous system named Batson's plexus communicating with the sacral, pelvic, and prostatic venous plexus. Our case indicated the importance of Batson's plexus in group B streptococcus infections surrounding the spinal canal and the necessity to explore for intrapelvic lesions including a rectal ulcer.

8. VIEW SHOWING THE DEMOSSING OF GRAND CANAL LOCATION UNKNOWN. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

8. VIEW SHOWING THE DEMOSSING OF GRAND CANAL LOCATION UNKNOWN. AT TEAM OF HORSES ON OPPOSITE BANKS OF THE CANAL DRAG A CHAIN BETWEEN THEM ALONG THE BOTTOM OF THE CANAL, WHICH PULLS THE MOSS AND WEEDS LOOSE. THE PLANS THEN FLOAT DOWN THE CANAL AND ARE CAUGHT IN A SCREEN AND REMOVED. Photographer unknown, 1923 - Grand Canal, North side of Salt River, Tempe, Maricopa County, AZ

[Quantitive study of interleukin 1beta in periapical exudates of chronic periapical periodontitis in the course of root canal therapy].

PubMed

Yan, Pei-fang; Liang, Jing-ping; Chen, Wei-min; Gu, Shen-sheng

2007-06-01

To evaluate the relationship between IL-1beta and clinical findings of chronic apical periodontitis and to explore the function of IL-1beta during the endodontic interappointment flare-ups. Periapical exudates samples were obtained from 19 teeth suffering from endodontic flare-ups after root canal preparation and 20 teeth without any symptoms and signs at the second visit after root canal preparation. The levels of IL-1beta were determined by ELISA and the data was analyzed by SAS6.12 software package. Significantly higher levels of IL-1beta were found in periapical exudates from teeth suffering from endodontic flare-ups than that before canal preparation(P<0.001). The mean IL-1beta levels significantly decreased following the endodontic therapy if there were no symptom at the second visit (P<0.001). The level of IL-1beta in the exudates of root canals were related with the exist of infection which might take an active part in the occurrence of endodontic interappointment flare-up.

28. VIEW FROM IMMEDIATELY DOWNSTREAM OF TWIN FALLS MAIN CANAL ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

28. VIEW FROM IMMEDIATELY DOWNSTREAM OF TWIN FALLS MAIN CANAL HEADWORKS WITH CANAL BRIDGE IN DISTANCE. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

32. VIEW OF TWIN FALLS MAIN CANAL FROM VICINITY OF ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

32. VIEW OF TWIN FALLS MAIN CANAL FROM VICINITY OF PROPOSED POWER CANAL, LOOKING UPSTREAM. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

Management of Acquired Atresia of the External Auditory Canal.

PubMed

Bajin, Münir Demir; Yılmaz, Taner; Günaydın, Rıza Önder; Kuşçu, Oğuz; Sözen, Tevfik; Jafarov, Shamkal

2015-08-01

The aim was to evaluate surgical techniques and their relationship to postoperative success rate and hearing outcomes in acquired atresia of the external auditory canal. In this article, 24 patients with acquired atresia of the external auditory canal were retrospectively evaluated regarding their canal status, hearing, and postoperative success. Acquired stenosis occurs more commonly in males with a male: female ratio of 2-3:1; it seems to be a disorder affecting young adults. Previous ear surgery (13 patients, 54.2%) and external ear trauma (11 patients, 45.8%) were the main etiological factors of acquired ear canal stenosis. Mastoidectomy (12/13) and traffic accidents (8/11) comprise the majority of these etiological factors. Endaural incision is performed in 79.2% and postauricular incision for 20.8% of cases during the operation. As types of surgical approach, transcanal (70.8%), transmastoid (20.8%), and combined (8.4%) approaches are chosen. The atretic plate is generally located at the bony-cartilaginous junction (37.5%) and in the cartilaginous canal (33.3%); the bony canal is involved in a few cases only. Preserved healthy canal skin, split- or full-thickness skin grafts, or pre- or postauricular skin flaps are used to line the ear canal, but preserved healthy canal skin is preferred. The results of surgery are generally satisfactory, and complications are few if surgical principles are followed.

Comparative study of ProTaper gold, reciproc, and ProTaper universal for root canal preparation in severely curved root canals

PubMed Central

Arslan, Hakan; Yildiz, Ezgi Doganay; Gunduz, Hicran Ates; Sumbullu, Meltem; Bayrakdar, Ibrahim Sevki; Karatas, Ertugrul; Sumbullu, Muhammed Akif

2017-01-01

Aim: The aim of this study is to evaluate the root canal transportation, centering ability, and instrumentation times with the ProTaper Gold (Dentsply Tulsa Dental, Tulsa, OK, USA), Reciproc (VDW, Munich, Germany), and ProTaper Universal (Dentsply Maillefer, Ballaigues, Switzerland) using cone-beam computed tomography (CBCT). Materials and Methods: Thirty mesial root canals of mandibular first molars with curvature angles of 35°–70° and radii of 2–6 mm were included in the study. Root canal instrumentation was performed up to F2 or R25. The instrumentation times were recorded. CBCT scanning was performed both pre- and post-instrumentation. Root canal transportation and the centering ratio were calculated for groups, and the data were analyzed using a one-way ANOVA and least significant difference post hoc tests for the instrumentation time, root canal transportation, and centering ratio at the 95% confidence level (P = 0.05). Results: At 3, 5, and 7 mm levels, there was no significant difference in the root canal transportation and centering ratio among the groups (P > 0.05). There were significant differences between the Reciproc and ProTaper Universal groups in the instrumentation times (P < 0.05). Conclusion: Root canal transportation and the centering ratio with the ProTaper Gold were similar to those obtained with the ProTaper Universal and Reciproc. PMID:29259355

The Age-Related Orientational Changes of Human Semicircular Canals.

PubMed

Lyu, Hui-Ying; Chen, Ke-Guang; Yin, Dong-Ming; Hong, Juan; Yang, Lin; Zhang, Tian-Yu; Dai, Pei-Dong

2016-06-01

Some changes are found in the labyrinth anatomy during postnatal development. Although the spatial orientation of semicircular canals was thought to be stable after birth, we investigated the age-related orientational changes of human semicircular canals during development. We retrospectively studied the computed tomography (CT) images of both ears of 76 subjects ranged from 1 to 70 years old. They were divided into 4 groups: group A (1-6 years), group B (7-12 years), group C (13-18 years), and group D (>18 years). The anatomical landmarks of the inner ear structures were determined from CT images. Their coordinates were imported into MATLAB software for calculating the semicircular canals orientation, angles between semicircular canal planes and the jugular bulb (JB) position. Differences between age groups were analyzed using multivariate statistics. Relationships between variables were analyzed using Pearson analysis. The angle between the anterior semicircular canal plane and the coronal plane, and the angle between the horizontal semicircular canal plane and the coronal plane were smaller in group D than those in group A (P<0.05). The JB position, especially the anteroposterior position of right JB, correlated to the semicircular canals orientation (P<0.05). However, no statistically significant differences in the angles between ipsilateral canal planes among different age groups were found. The semicircular canals had tendencies to tilt anteriorly simultaneously as a whole with age. The JB position correlated to the spatial arrangement of semicircular canals, especially the right JB. Our calculation method helps detect developmental and pathological changes in vestibular anatomy.

2. BLACK RIVER CANAL SUPPLY FROM END OF MAIN ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

2. BLACK RIVER CANAL - SUPPLY FROM END OF MAIN CANAL TO BLACK RIVER. VIEW TO SOUTHWEST - Carlsbad Irrigation District, Black River Canal, 15 miles Southeast of Carlsbad near Malaga, Carlsbad, Eddy County, NM

28. MAIN CANAL Photographic copy of historic photo, July ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

28. MAIN CANAL - Photographic copy of historic photo, July 18, 1906 (original print located at the Carlsbad Irrigation District offices, Carlsbad, New Mexico) J.J. Lubken, photographer 'LOOKING SOUTH FROM STATION 413, ON THE MAIN CANAL, SHOWING THE REMODLING SIC OF THE OLD PECOS VALLEY IRRIGATING CANAL' - Carlsbad Irrigation District, Main Canal, 4 miles North to 12 miles Southeast of Carlsbad, Carlsbad, Eddy County, NM

88. CEDAR DRAW SPILL, HIGH LINE CANAL, TWIN FALLS COUNTY, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

88. CEDAR DRAW SPILL, HIGH LINE CANAL, TWIN FALLS COUNTY, SOUTH OF FILER, IDAHO; WEST VIEW OF CANAL AND GATES. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

97. POINT SPILL, TWIN FALLS MAIN CANAL, TWIN FALLS COUNTY ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

97. POINT SPILL, TWIN FALLS MAIN CANAL, TWIN FALLS COUNTY NORTHWEST OF MURTAUGH, IDAHO; OVERALL WEST VIEW FROM CANAL SIDE. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

149. TWIN FALLS MAIN CANAL DIVERSION, TWIN FALLS COUNTY, MILNER ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

149. TWIN FALLS MAIN CANAL DIVERSION, TWIN FALLS COUNTY, MILNER DAM; CLOSE-UP OF MAIN CANAL GATES, SOUTH VIEW. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

91. CEDAR DRAW SPILL, HIGH LINE CANAL, TWIN FALLS COUNTY, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

91. CEDAR DRAW SPILL, HIGH LINE CANAL, TWIN FALLS COUNTY, SOUTH OF FILER, IDAHO; NORTHEAST VIEW OF CANAL AND GATES. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

89. CEDAR DRAW SPILL, HIGH LINE CANAL, TWIN FALLS COUNTY, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

89. CEDAR DRAW SPILL, HIGH LINE CANAL, TWIN FALLS COUNTY, SOUTH OF FILER, IDAHO; OUTLET SIDE OF CANAL, SOUTHWEST VIEW. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

3. Dundee Canal looking northwest from north of Dundee Textile ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

3. Dundee Canal looking northwest from north of Dundee Textile Company Mill - Dundee Canal Industrial Historic District, Beginning at George Street in Passaic & extending north along Dundee Canal approximately 1.2 miles to Canal headgates opposite East Clifton Avenue in Clifton, Passaic, Passaic County, NJ

Root canal preparation with a novel nickel-titanium instrument evaluated with micro-computed tomography: canal surface preparation over time.

PubMed

Peters, Ove A; Boessler, Claudia; Paqué, Frank

2010-06-01

The aim of this part of an ongoing study was to describe the dentin removal ability of a novel nickel-titanium instrument, the self-adjusting file (SAF), by using micro-computed tomography. Twenty maxillary incisors were scanned preoperatively at 20-microm resolution and postoperatively after up to 6 minutes of preparation with an SAF with 1.5-mm or 2-mm diameter. SAFs were operated with continuous irrigation in a handpiece that provided an oscillating, in-and-out movement. Changes in canal volume compared with preoperative values as well as unprepared canal surface area were determined. Data were normally distributed and compared by analysis of variance and regression analyses. Preoperatively canal volumes were statistically similar in both groups (9.86 +/- 3.97 mm3 and 9.80 +/- 2.67 mm3). Volumes increased during preparation to 13.58 +/- 3.85 mm3 (after 6 minutes with SAF 1.5 mm) and 16.43 +/- 3.64 mm3 (after 5 minutes with SAF 2.0 mm), and overall canal shapes were adequate. Unprepared canal surface area decreased from 63.0% +/- 15.1% (2 minutes with SAF 1.5 mm) to 8.6% +/- 4.1% (5 minutes with SAF 2.0 mm). Preparation of straight root canals in maxillary anterior teeth left little canal surface uninstrumented after shaping with the SAF. The timeframe of clinical application will depend on the amount of desired dentin removal and done with an SAF selected on the basis of apical gauging. Copyright 2010 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

94. CEDAR DRAW SPILL, LOW LINE CANAL, TWIN FALLS COUNTY ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

94. CEDAR DRAW SPILL, LOW LINE CANAL, TWIN FALLS COUNTY SOUTH OF FILER, IDAHO; CLOSE-UP OF GATES FROM THE CANAL SIDE. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

Panama Canal Zone as seen from STS-62

NASA Image and Video Library

1994-03-05

STS062-85-095 (4-18 March 1994) --- Gatun Lake and the forested Panama Canal Zone can be seen in this north northwest-looking low oblique photograph obtained in March 1994. The shipping chanel of the canal is 82.4 kilometers (51.2 miles) long, though the canal zone is only 65 kilometers (40 miles) long. The width of the canal zones extends generally 8 kilometers (5 miles) on either side of the shipping channel, except near Madden Lake. The canal connects the Atlantic Ocean (coastal city of Colon) with the Pacific Ocean near Panama City in a line that takes a northwest to southeast course because of the configuration of the isthmus. The canal zigzags across the isthmus to take advantage of the geographic features of the area such as the Chagres River. The controlled water supply for the canal is provided by the three artificial lakes: Gatun near the Atlantic terminus, Miraflores near the Pacific terminus and Madden about halfway across the isthmus. Gatun is the largest of the three lakes covering an area of 429 square kilometers (165 square miles). In the midst of this lake is Barro Colorado Island, a world-famous wild game perserve. Madden Lake was built as a large supplemental reservoir to keep water levels up in the canal during the dry season. All three lakes are vital sources of water for maintaining the ship channel over the continental divide (Gaillard Cut) and for regulating the flow of water that enables hugh vessels to be lifted and lowered in massive locks.

Micro-CT analyses of apical enlargement and molar root canal complexity.

PubMed

Markvart, M; Darvann, T A; Larsen, P; Dalstra, M; Kreiborg, S; Bjørndal, L

2012-03-01

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. Maxillary and mandibular molar teeth were scanned using X-ray microcomputed tomography. Root canals were prepared using either a GT/Profile protocol or a RaCe/NiTi protocol. Variables used for evaluation were the following: distance between root canal surfaces before and after preparation (distance after preparation, DAP), percentage of root canal area remaining unprepared and increase in canal volume after preparation. Root canals were classified according to size and complexity, and consequences of unprepared portions of narrow root canals and intraradicular connections/isthmuses were included in the analyses. One- and two-way anova were used in the statistical analyses. No difference was found between the two techniques: DAP(apical-third) (P = 0.590), area unprepared(apical-third) (P = 0.126) and volume increase(apical-third) (P = 0.821). Unprepared root canal area became larger in relation to root canal size and complexity, irrespective of the technique used. Percentage of root canal area remaining unprepared was significantly lower in small root canals and complex systems compared to large root canals. The isthmus area per se contributed with a mean of 17.6%, and with a mean of 25.7%, when a narrow root canal remained unprepared. The addition of isthmuses did not significantly alter the ratio of instrumented to unprepared areas at total root canal level. Distal and palatal root canals had the highest level of unprepared area irrespective of the two instrumentation techniques examined. © 2011 International Endodontic Journal.

Looking back at Love Canal

DOE Office of Scientific and Technical Information (OSTI.GOV)

Deegan, J. Jr.

In the first part of this series (ES and T, April 1987, pp. 328-31) it was pointed out that the methods and conclusions of EPA's Love Canal Study were the subject of some controversy in the environmental community. Others defended the agency's approaches and methods. Part 2 makes no attempt to resolve the controversy; its purpose is to present the results and conclusions of the Love Canal.

123. MCMULLEN CREEK, HIGH LINE CANAL, TWIN FALLS COUNTY, SOUTH ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

123. MCMULLEN CREEK, HIGH LINE CANAL, TWIN FALLS COUNTY, SOUTH OF KIMBERLY, IDAHO; SOUTH VIEW OF THE CREEK EMPTYING INTO THE HIGH LINE CANAL. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

189. Photocopy of drawing, Twin Falls Canal Company, date unknown. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

189. Photocopy of drawing, Twin Falls Canal Company, date unknown. ROCK CREEK CROSSING, LOW LINE CANAL, TWIN FALLS COUNTY, SOUTH OF KIMBERLY, IDAHO; BLUEPRINT. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

131. FORKS DIVERSION, HIGH LINE AND LOW LINE CANALS, TWIN ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

131. FORKS DIVERSION, HIGH LINE AND LOW LINE CANALS, TWIN FALLS COUNTY, SOUTH OF HANSEN, IDAHO; INLET SIDE OF LOW LINE CANAL, WEST VIEW. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

Anthropometry of external auditory canal by non-contactable measurement.

PubMed

Yu, Jen-Fang; Lee, Kun-Che; Wang, Ren-Hung; Chen, Yen-Sheng; Fan, Chun-Chieh; Peng, Ying-Chin; Tu, Tsung-Hsien; Chen, Ching-I; Lin, Kuei-Yi

2015-09-01

Human ear canals cannot be measured directly with existing general measurement tools. Furthermore, general non-contact optical methods can only conduct simple peripheral measurements of the auricle and cannot obtain the internal ear canal shape-related measurement data. Therefore, this study uses the computed tomography (CT) technology to measure the geometric shape of the ear canal and the shape of the ear canal using a non-invasive method, and to complete the anthropometry of external auditory canal. The results of the study show that the average height and width of ear canal openings, and the average depth of the first bend for men are generally longer, wider and deeper than those for women. In addition, the difference between the height and width of the ear canal opening is about 40% (p < 0.05). Hence, the circular cross-section shape of the earplugs should be replaced with an elliptical cross-section shape during manufacturing for better fitting. Copyright © 2015 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Mammary Gland Pathology Subsequent to Acute Infection with Strong versus Weak Biofilm Forming Staphylococcus aureus Bovine Mastitis Isolates: A Pilot Study Using Non-Invasive Mouse Mastitis Model.

PubMed

Gogoi-Tiwari, Jully; Williams, Vincent; Waryah, Charlene Babra; Costantino, Paul; Al-Salami, Hani; Mathavan, Sangeetha; Wells, Kelsi; Tiwari, Harish Kumar; Hegde, Nagendra; Isloor, Shrikrishna; Al-Sallami, Hesham; Mukkur, Trilochan

2017-01-01

Biofilm formation by Staphylococcus aureus is an important virulence attribute because of its potential to induce persistent antibiotic resistance, retard phagocytosis and either attenuate or promote inflammation, depending upon the disease syndrome, in vivo. This study was undertaken to evaluate the potential significance of strength of biofilm formation by clinical bovine mastitis-associated S. aureus in mammary tissue damage by using a mouse mastitis model. Two S. aureus strains of the same capsular phenotype with different biofilm forming strengths were used to non-invasively infect mammary glands of lactating mice. Biofilm forming potential of these strains were determined by tissue culture plate method, ica typing and virulence gene profile per detection by PCR. Delivery of the infectious dose of S. aureus was directly through the teat lactiferous duct without invasive scraping of the teat surface. Both bacteriological and histological methods were used for analysis of mammary gland pathology of mice post-infection. Histopathological analysis of the infected mammary glands revealed that mice inoculated with the strong biofilm forming S. aureus strain produced marked acute mastitic lesions, showing profuse infiltration predominantly with neutrophils, with evidence of necrosis in the affected mammary glands. In contrast, the damage was significantly less severe in mammary glands of mice infected with the weak biofilm-forming S. aureus strain. Although both IL-1β and TNF-α inflammatory biomarkers were produced in infected mice, level of TNF-α produced was significantly higher (p<0.05) in mice inoculated with strong biofilm forming S. aureus than the weak biofilm forming strain. This finding suggests an important role of TNF-α in mammary gland pathology post-infection with strong biofilm-forming S. aureus in the acute mouse mastitis model, and offers an opportunity for the development of novel strategies for reduction of mammary tissue damage, with or without

Bacterial examination of endodontic infections by clonal analysis in concert with denaturing high-performance liquid chromatography.

PubMed

Jacinto, R C; Gomes, B P F A; Desai, M; Rajendram, D; Shah, H N

2007-12-01

The aim of this study was to examine the diversity of bacterial species in the infected root canals of teeth associated with endodontic abscesses by cloning and sequencing techniques in concert with denaturing high-performance liquid chromatography. Samples collected from five infected root canals were subjected to polymerase chain reaction (PCR) with universal 16S ribosomal DNA primers. Products of these PCRs were cloned and sequenced. Denaturing high-performance liquid chromatography (DHPLC) was used as a screening method to reduce the number of clones necessary for DNA sequencing. All samples were positive for the presence of bacteria and a range of 7-13 different bacteria were found per root canal sample. In total, 48 different oral clones were detected among the five root canal samples. Olsenella profusa was the only species present in all samples. Porphyromonas gingivalis, Dialister pneumosintes, Dialister invisus, Lachnospiraceae oral clone, Staphylococcus aureus, Pseudoramibacter alactolyticus, Peptostreptococcus micros and Enterococcus faecalis were found in two of the five samples. The majority of the taxa were present in only one sample, for example Tannerella forsythia, Shuttleworthia satelles and Filifactor alocis. Some facultative anaerobes that are frequently isolated from endodontic infections such as E. faecalis, Streptococcus anginosus and Lactobacillus spp. were also found in this study. Clonal analysis of the microflora associated with endodontic infections revealed a wide diversity of oral species.

2. View looking northeast; Dundee Canal headgates and guardlock in ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

2. View looking northeast; Dundee Canal headgates and guardlock in foreground, Dundee Dam and Passaic River in background - Dundee Canal Industrial Historic District, Beginning at George Street in Passaic & extending north along Dundee Canal approximately 1.2 miles to Canal headgates opposite East Clifton Avenue in Clifton, Passaic, Passaic County, NJ

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

USGS Publications Warehouse

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

Functional Implications of Ubiquitous Semicircular Canal Non-Orthogonality in Mammals

PubMed Central

Berlin, Jeri C.; Kirk, E. Christopher; Rowe, Timothy B.

2013-01-01

The ‘canonical model’ of semicircular canal orientation in mammals assumes that 1) the three ipsilateral canals of an inner ear exist in orthogonal planes (i.e., orthogonality), 2) corresponding left and right canal pairs have equivalent angles (i.e., angle symmetry), and 3) contralateral synergistic canals occupy parallel planes (i.e., coplanarity). However, descriptions of vestibular anatomy that quantify semicircular canal orientation in single species often diverge substantially from this model. Data for primates further suggest that semicircular canal orthogonality varies predictably with the angular head velocities encountered in locomotion. These observations raise the possibility that orthogonality, symmetry, and coplanarity are misleading descriptors of semicircular canal orientation in mammals, and that deviations from these norms could have significant functional consequences. Here we critically assess the canonical model of semicircular canal orientation using high-resolution X-ray computed tomography scans of 39 mammal species. We find that substantial deviations from orthogonality, angle symmetry, and coplanarity are the rule for the mammals in our comparative sample. Furthermore, the degree to which the semicircular canals of a given species deviate from orthogonality is negatively correlated with estimated vestibular sensitivity. We conclude that the available comparative morphometric data do not support the canonical model and that its overemphasis as a heuristic generalization obscures a large amount of functionally relevant variation in semicircular canal orientation between species. PMID:24260256

Single-rooted maxillary first molar with a single canal: endodontic retreatment.

PubMed

de la Torre, Francisco; Cisneros-Cabello, Rafael; Aranguren, José Luis; Estévez, Roberto; Velasco-Ortega, Eugenio; Segura-Egea, Juan José

2008-12-01

This case report presents an unusual root canal system in a maxillary first molar tooth: a single canal in a single root. The endodontic access cavity displayed only 1 canal orifice. This case demonstrated that: 1) clinicians must have adequate knowledge about root canal morphology and its variations; 2) the location and morphology of root canals should be identified radiologically before the root canal treatment; and 3) careful examination of radiographs and the internal anatomy of teeth is essential.

[Root canal treatment of mandibular second premolar tooth with taurodontism].

PubMed

Vujasković, Mirjana; Karadzić, Branislav; Miletić, Vesna

2008-01-01

Taurodontism is a morphoanatomical change in the shape of a tooth. An enlarged body of a tooth with smaller than usual roots is a characteristic feature. Internal tooth anatomy correlates with this appearance, which means that a taurodontal tooth has a large pulp chamber and apically positioned furcations. This dental anomaly may be associated with different syndromes and congenital discoders. The case report presents the patient of a rare case of taurodontism in the mandibular second premolar with chronic periodontitis. Endodontic treatment was performed after dental history and clinical examination. Special care is required in all segments of endodontic treatment of a taurodontal tooth from the identification orifice, canal exploration, determining working length, cleaning and shaping and obturation of the root canal. Precurved K-file was used for canal exploration and location of the furcation. One mesial and one distal canal with the buccal position were identified in the apical third of the root canal. The working lengths of two canals were determined by radiographic interpretation with two K-files in each canal and verified with the apex locator. During canal instrumentation, the third canal was located in the disto-lingual position. The working length of the third canal was established using the apex locator. Thorough knowledge of tooth anatomy and its variations can lead to lower percentage of endodontic failure. Each clinical case involving these teeth should be investigated carefully, clinically and radiographically to detect additional root canals. High quality radiographs from different angles and proper instrumentarium improve the quality of endodontic procedure.

Comparative evaluation of calcium hypochlorite and sodium hypochlorite associated with passive ultrasonic irrigation on antimicrobial activity of a root canal system infected with Enterococcus faecalis: an in vitro study.

PubMed

de Almeida, Ana Paula; Souza, Matheus Albino; Miyagaki, Daniela Cristina; Dal Bello, Yuri; Cecchin, Doglas; Farina, Ana Paula

2014-12-01

The purpose of this study was to compare in vitro the effectiveness of calcium hypochlorite (Ca[OCl]2) and sodium hypochlorite (NaOCl) associated with passive ultrasonic irrigation in root canals of bovine teeth infected with Enterococcus faecalis. The root canals of 60 single-rooted bovine extracted teeth were enlarged up to a file 45, autoclaved, inoculated with Enterococcus faecalis, and incubated for 30 days. The samples were divided into 6 groups (n = 10) according to the protocol for decontamination: G1: no treatment; G2: distilled water; G3: 2.5% NaOCl; G4: 2.5% Ca(OCl)2; G5: 2.5% NaOCl with ultrasonic activation; and G6: 2.5% Ca(OCl)2 with ultrasonic activation (US). Microbiological testing (colony-forming unit [CFU] counting) was performed to evaluate and show, respectively, the effectiveness of the proposed treatments. Data were subjected to 1-way analysis of variance followed by the post hoc Tukey test (α = 0.05). Groups 1 and 2 showed the highest mean contamination (3.26 log10 CFU/mL and 2.69 log10 CFU/mL, respectively), which was statistically different from all other groups (P < .05). Group 6 (Ca[OCl]2 + US) showed the lowest mean contamination (1.00 log10 CFU/mL), with no statistically significant difference found in groups 3 (NaOCl), 4 (Ca[OCl]2), and 5 (NaOCl + US) (P < .05). Ca(OCl)2 as well as passive ultrasonic irrigation can aid in chemomechanical preparation, contributing in a significant way to the reduction of microbial content during root canal treatment. Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

[Upper lateral incisor with 2 canals].

PubMed

Fabra Campos, H

1991-01-01

Clinical case summary of the patient with an upper lateral incisor with two root canals. The suspicion that there might be an anatomic anomaly in the root that includes a complex root canal system was made when an advanced radicular groove was detected in the lingual surface or an excessively enlarged cingulum.

[Influence of different ultrasonic irrigation solutions after root canal preparation with ProTaper by machine on micro-hardness of root canal dentin].

PubMed

Guo, Jiang-li; Zhang, Yan; Zhen, Lei

2015-08-01

To develope the influence of different ultrasonic irrigations after root canal preparation with nickel titanium ProTaper on micro-hardness of root canal dentin. Sixty of maxillary anterior teeth with single-canal were collected and randomly divided into 6 groups. Group A was control group, group B was prepared to F3 with nickel titanium ProTaper by machine, group C was ultrasonic irrigated with 3% hydrogen peroxide solution for 1 minute after preparation, group D was ultrasonic irrigated with koutai mouthwash for 1 minute after preparation, group E was ultrasonic irrigated with 17% EDTA solution for 1 minute after preparation, group F was ultrasonic irrigated with distilled water for 1 minute after preparation. The roots were then sectioned horizontally into 3 parts, split longitudinally into halves and examined under a micro Vickers hardness test machine. The data was analyzed by one-way ANOVA and t test with SPSS 17.0 software package. The micro-hardness of group A was (52.66 ± 1.64) HV,(52.08 ± 1.53) HV and (51.47 ± 2.53) HV. There was no significant difference in all parts of the root canal in group A (P>0.05). The micro-hardness of the apical third of root canal was lower than that of the cervical and middle of root canal in the other groups (P<0.05). In the cervical and middle third of the root canals, the micro-hardness of group E was (44.65 ± 1.33) HV and(42.55 ± 1.12) HV, and there were statistical significances between group E and the other groups (P<0.05). In the apical third of root canal,the micro-hardness of group E was (37.82 ± 1.60) HV, and group C was (44.14±1.73) HV, both of the comparative differences with other groups were statistically significant (P<0.05). There was no significant difference among group B, group D and group F (P>0.05). Root canal preparation to F3 with nickel titanium ProTaper by machine can make the micro-hardness of the apical third of root canal decrease. Ultrasonic irrigation with 17% EDTA solution for 1 minute can

Environmental pollution and shipping feasibility of the Nicaragua Canal.

PubMed

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.

Root canal microbiota of teeth with chronic apical periodontitis.

PubMed

Rôças, I N; Siqueira, J F

2008-11-01

Samples from infected root canals of 43 teeth with chronic apical periodontitis were analyzed for the presence and relative levels of 83 oral bacterial species and/or phylotypes using a reverse-capture checkerboard hybridization assay. Associations between the most frequently detected taxa were also recorded. The most prevalent taxa were Olsenella uli (74%), Eikenella corrodens (63%), Porphyromonas endodontalis (56%), Peptostreptococcus anaerobius (54%), and Bacteroidetes oral clone X083 (51%). When prevalence was considered only for bacteria present at levels >10(5), Bacteroidetes clone X083 was the most frequently isolated bacterium (37%), followed by Parvimonas micra (28%), E. corrodens (23%), and Tannerella forsythia (19%). The number of target taxa per canal was directly proportional to the size of the apical periodontitis lesion, with lesions >10 mm in diameter harboring a mean number of approximately 20 taxa. Several positive associations for the most prevalent taxa were disclosed for the first time and may have important ecological and pathogenic implications. In addition to strengthening the association of several cultivable named species with chronic apical periodontitis, the present findings using a large-scale analysis allowed the inclusion of some newly named species and as-yet-uncultivated phylotypes in the set of candidate pathogens associated with this disease.

158. Photocopy of transit book (taken from Twin Falls Canal ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

158. Photocopy of transit book (taken from Twin Falls Canal Company Transit Book #404T, Page 3, #46, Division One). START OF MAIN CANAL SURVEY, TWIN FALLS COUNTY, MILNER, IDAHO. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

Decline in semicircular canal and otolith function with age

PubMed Central

Agrawal, Yuri; Zuniga, M. Geraldine; Davalos-Bichara, Marcela; Schubert, Michael C.; Walston, Jeremy D.; Hughes, Jennifer; Carey, John P.

2012-01-01

Objective To characterize the physiologic nature of the vestibular dysfunction that occurs with the normative aging process. Study design Cross-sectional study. Setting Tertiary care academic medical center. Patients Fifty individuals age 70 and above. Interventions Head thrust dynamic visual acuity testing (htDVA) and cervical and ocular vestibular-evoked myogenic potential (VEMP) testing. Main Outcome Measures Semicircular canal function measured by htDVA in each of the three semicircular canal planes, and saccular and utricular function measured by cVEMP and oVEMP testing, respectively. Results We observed significant declines in semicircular canal function in each of the canal planes as well as otolith function associated with aging. We found that individuals with impaired horizontal and superior semicircular canal function were likely to also have concomitant deficits in utricular but not saccular function. Overall, we noted that the prevalence of semicircular canal dysfunction was highest followed by saccular then utricular impairment, although we did observe individuals with isolated otolith deficits. Conclusions These data suggest an overall decline in semicircular canal as well as otolith function associated with aging, although the magnitude of impairment was greater for the semicircular canals than the otoliths in this elderly population. A better understanding of the specific vestibular deficits that occur with aging can inform the development of rational screening, vestibular rehabilitation and fall risk reduction strategies in older individuals. PMID:22699991

150. Photocopy of drawing (taken from Twin Falls Canal Company ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

150. Photocopy of drawing (taken from Twin Falls Canal Company Surveyor's Book #363, Page 42, entitled, 'Diversion Tunnels', located in Twin Falls Canal Company office, Twin Falls, Idaho). PLAN OF DIVERSION TUNNELS, MILNER DAM. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

180. Photocopy of Photograph, Twin Falls Canal Company. E. Pettygro, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

180. Photocopy of Photograph, Twin Falls Canal Company. E. Pettygro, Photographer, date unknown. BLASTING TWIN FALLS CANAL, TWIN FALLS COUNTY; BLASTING COTTONWOOD AREA TO REPLACE FLUME BY RUNNING HIGH LINE THROUGH SOLID ROCK. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

177. Photocopy of Photograph, Twin Falls Canal Company, Bisbee Photo, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

177. Photocopy of Photograph, Twin Falls Canal Company, Bisbee Photo, September, 1912. Photographer unknown. COTTONWOOD FLUME, HIGH LINE CANAL, TWIN FALLS COUNTY, SOUTH OF KIMBERLY, IDAHO; SOUTH VIEW FROM UPPER SIDE. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

Root and Root Canal Morphology of Human Third Molar Teeth.

PubMed

Mohammadi, Zahed; Jafarzadeh, Hamid; Shalavi, Sousan; Bandi, Shilpa; Patil, Shankargouda

2015-04-01

Successful root canal treatment depends on having comprehensive information regarding the root(s)/canal(s) anatomy. Dentists may have some complication in treatment of third molars because the difficulty in their access, their aberrant occlusal anatomy and different patterns of eruption. The aim of this review was to review and address the number of roots and root canals in third molars, prevalence of confluent canals in third molars, C-shaped canals, dilaceration and fusion in third molars, autotransplantation of third molars and endodontic treatment strategies for third molars.

3. August, 1971. VIEW ALONG CANAL SHOWING BORDER PATH AND ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

3. August, 1971. VIEW ALONG CANAL SHOWING BORDER PATH AND BRIDGE FOR INSPECTION - ABOUT ONE MILE FROM CANAL HEAD. - Hurricane Irrigation Canal, State Route 15 Vicinity, Hurricane, Washington County, UT

154. Photocopy of transit book (taken from Twin Falls Canal ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

154. Photocopy of transit book (taken from Twin Falls Canal Company Surveyor's Transit Book #405T, Page 2, #46 Division One). STATEMENT OF SIGHT-SETTING FOR 1903 SURVEY TO ALIGN SOUTH SIDE CANAL, TWIN FALLS COUNTY, MILNER, IDAHO. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

The Use of a Novel Approach for the Instrumentation of a Cone-beam Computed Tomography-discernible Lateral Canal in an Unusual Maxillary Incisor: Case Report.

PubMed

Chaniotis, Antonis; Filippatos, Christos G

2017-06-01

Lateral and apical ramifications of the main root canal create potential pathways through which bacteria can spread and remain unaffected by treatment procedures. It is a challenge for the specialty to find techniques that can predictably reach, disinfect, and obturate these ramifications. Here, we report the use of a novel instrumentation approach to aid in the negotiation and management of a lateral canal discernible on cone-beam computed tomography (CBCT) in an unusual maxillary central incisor. A 23-year-old female patient was referred for evaluation and possible treatment of tooth 9. The periapical radiographic examination revealed pulp chamber obliteration, existence of a lateral lesion, and a possible complex internal root canal anatomy. The CBCT evaluation revealed the existence of a lateral lesion, a periapical lesion, an additional distopalatal canal, and a lateral canal exiting at the lateral lesion. The diagnosis of asymptomatic apical and lateral periodontitis of tooth 9 was reached. CBCT-aided access cavity preparation and scouting resulted in the successful negotiation of all canals, main and lateral. A novel instrumentation technique with precurved controlled memory files was used for the mechanical preparation of the lateral canal to a 25/04 enlargement. Obturaton of the lateral canal was achieved with a single gutta-percha cone and AH Plus Root Canal Sealer. At the 2-year follow-up, the patient was asymptomatic, and the 2-dimensional radiographic examinations revealed resolution of both the periapical and the lateral lesions. This case report describes the application of a novel instrumentation technique for the mechanical debridement of an infected lateral canal discernible on CBCT and reinforces the importance of treating the root canals as systems that possesses anatomic intricacies that need to be addressed. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

C-shaped root canal in a maxillary first molar: a case report.

PubMed

Yilmaz, Z; Tuncel, B; Serper, A; Calt, S

2006-02-01

This case report presents an unusual C-shaped root canal system in a maxillary first molar tooth. Although C-shaped root canals are most frequently seen in the mandibular second molar, they may also appear in maxillary molars. A literature search revealed only a few case reports of C-shaped root canal systems in maxillary molars. The present case describes a C-shaped canal in the buccal root of a maxillary first molar. The endodontic access cavity displayed two canal orifices, one leading to the canal system in the buccal root, the other into the palatal root canal system. In the buccal root, what appeared to be the mesial and distal canals joined to form a single C-shaped canal. --Careful examination of radiographs and the internal anatomy of teeth is essential.-- The location and morphology of root canals should be identified at high magnification under the microscope.

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

PubMed

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.

Lock No. 1 St. Lucie Canal. Upper gate structure, masonry ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Lock No. 1- St. Lucie Canal. Upper gate structure, masonry plan- masonry elevations. - St. Lucie Canal, St. Lucie Lock No. 1, St. Lucie, Cross State Canal, Okeechobee Intracoastal Waterway, Stuart, Martin County, FL

Dundee Canal Industrial Historic District, Beginning at George Street in ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Dundee Canal Industrial Historic District, Beginning at George Street in Passaic & extending north along Dundee Canal approximately 1.2 miles to Canal headgates opposite East Clifton Avenue in Clifton, Passaic, Passaic County, NJ

14. VIEW OF WESTERN CANAL AT THE SALT RIVER PROJECT'S ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

14. VIEW OF WESTERN CANAL AT THE SALT RIVER PROJECT'S KYRENE STEAM POWER PLANT, TEMPE. THE WESTERN CANAL BEGINS TO TURN NORTH AT THIS POINT, AND DIVERTS WATER TO THE HIGHLINE PUMP PLANT AND THE KYRENE LATERAL. THE KYRENE PLANT INLET (LEFT-CENTER) ALSO DIVERTS CANAL WATER FOR PLANT OPERATION AND COOLING. - Western Canal, South side of Salt River between Tempe, Phoenix & Mesa, Mesa, Maricopa County, AZ

The Effect of Diode Laser on Planktonic Enterococcus faecalis in Infected Root Canals in an Ex Vivo Model.

PubMed

Cretella, Gilda; Lajolo, Carlo; Castagnola, Raffaella; Somma, Francesco; Inchingolo, MariaTeresa; Marigo, Luca

2017-04-01

This study examined the bactericidal effect of diode laser irradiation against intracanal Enterococcus faecalis. m total of 128 extracted single-rooted and single-canal teeth were treated with ProTaper instruments (Dentsply Maillefer, Ballaigues, Switzerland). A total of 120 root canals were inoculated with E. faecalis for 21 days, and the samples were randomly divided into five groups: Group 1 (n = 24) samples were irrigated with only saline solution (positive controls); Group 2 (n = 24) was treated with only 5.25% sodium hypochlorite; Group 3 (n = 24) was irrigated with saline solutions activated by diode laser; Group 4 (n = 24) was treated with 5.25% sodium hypochlorite activated by diode laser; and Group 5 (n = 24) was irrigated with saline solution with methylene blue dye activated by the diode laser Fox (Sweden & Martina, Padova, Italy); additionally, eight teeth were not contaminated and their canals were irrigated with saline solution and used as a negative control. The Uro-Quick system was used to determine the microbial residual charge. The data were analyzed using Pearson's chi-square test (p < 0.001). A statistically significant reduction in bacterial count was observed in Group 2 and Group 4 (p < 0.001). There were no statistically significant differences among the other groups (p > 0.001). Evidence indicates that the diode laser was not more effective than sodium hypochlorite in reducing free bacteria.

Biofilm forming ability of bacteria isolated from necrotic roots canals of teeth

NASA Astrophysics Data System (ADS)

Alwan, Merriam Ghadhanfar; Usup, Gires; Heng, Lee Yook; Ahmad, Asmat

2018-04-01

The growth of microbes in biofilms are associated with repeated and chronic human infections and are extremely resistant to antimicrobial agents. The purpose of this study was to determine the diversity of bacteria from necrotic roots canals of teeth and to detect their biofilm formation ability. A total of 42 bacterial isolates were isolated and identified as belonging to 11 genera. These are Enterococcus sp. (21.4%) followed by Streptococcus sp. (16.8%), Bacillus sp. (11.9%), Peptostreptococcus sp. (9.5%), Staphylococcus sp. (9.5%), Bacteroides sp. (7.1%), Clostridium sp. (7.1%), Actinomyces sp. (7.1%), Fusobacterium sp. (4.76%), Provotella sp. (2.4%) and Chromobacterium sp. (2.4%). Three screening methods for biofilm forming ability were used. Congo Red Agar method (CRA), Tube method (TM) and Microtitre Plate (MTP). From the results, MTP method is a more reliable and quantitative method for the screening and detection of microorganism's ability to form biofilm. This method can be recommended and suggested as a general screening method for the detection of biofilm forming bacteria isolated from roots canals of teeth.

The Dorello canal: historical development, controversies in microsurgical anatomy, and clinical implications.

PubMed

Kshettry, Varun R; Lee, Joung H; Ammirati, Mario

2013-03-01

Interest in studying the anatomy of the abducent nerve arose from early clinical experience with abducent palsy seen in middle ear infection. Primo Dorello, an Italian anatomist working in Rome in the early 1900s, studied the anatomy of the petroclival region to formulate his own explanation of this pathological entity. His work led to his being credited with the discovery of the canal that bears his name, although this structure had been described 50 years previously by Wenzel Leopold Gruber. Renewed interest in the anatomy of this region arose due to advances in surgical approaches to tumors of the petroclival region and the need to explain the abducent palsies seen in trauma, intracranial hypotension, and aneurysms. The advent of the surgical microscope has allowed more detailed anatomical studies, and numerous articles have been published in the last 2 decades. The current article highlights the historical development of the study of the Dorello canal. A review of the anatomical studies of this structure is provided, followed by a brief overview of clinical considerations.

26. DETAIL OF HEADGATE HOIST MACHINERY, TWIN FALLS MAIN CANAL. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

26. DETAIL OF HEADGATE HOIST MACHINERY, TWIN FALLS MAIN CANAL. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

Determination of canal leakage potential using continuous resistivity profiling techniques, Interstate and Tri-State Canals, western Nebraska and eastern Wyoming, 2004

USGS Publications Warehouse

Ball, Lyndsay B.; Kress, Wade H.; Steele, Gregory V.; Cannia, James C.; Andersen, Michael J.

2006-01-01

In the North Platte River Basin, a ground-water model is being developed to evaluate the effectiveness of using water leakage from selected irrigation canal systems to enhance ground-water recharge. The U.S. Geological Survey, in cooperation with the North Platte Natural Resources District, used land-based capacitively coupled and water-borne direct-current continuous resistivity profiling techniques to map the lithology of the upper 8 meters and to interpret the relative canal leakage potential of 110 kilometers of the Interstate and Tri-State Canals in western Nebraska and eastern Wyoming. Lithologic descriptions from 25 test holes were used to evaluate the effectiveness of both techniques for indicating relative grain size. An interpretive color scale was developed that symbolizes contrasting resistivity features indicative of different grain-size categories. The color scale was applied to the vertically averaged resistivity and used to classify areas of the canals as having either high, moderate, or low canal leakage potential. When results were compared with the lithologic descriptions, both land-based and water-borne continuous resistivity profiling techniques were determined to be effective at differentiating coarse-grained from fine-grained sediment. Both techniques were useful for producing independent, similar interpretations of canal leakage potential.

24. TWIN FALLS MAIN CANAL HEADWORKS, DOWNSTREAM LOOKING TOWARD THE ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

24. TWIN FALLS MAIN CANAL HEADWORKS, DOWNSTREAM LOOKING TOWARD THE EAST. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

29. VIEW OF TWIN FALLS MAIN CANAL BRIDGE FROM UPSTREAM ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

29. VIEW OF TWIN FALLS MAIN CANAL BRIDGE FROM UPSTREAM LOOKING DOWNSTREAM. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

31. VIEW OF TWIN FALLS MAIN CANAL BRIDGE FROM DOWNSTREAM ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

31. VIEW OF TWIN FALLS MAIN CANAL BRIDGE FROM DOWNSTREAM LOOKING UPSTREAM. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

30. VIEW OF TWIN FALLS MAIN CANAL FROM BRIDGE LOOKING ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

30. VIEW OF TWIN FALLS MAIN CANAL FROM BRIDGE LOOKING WEST DOWNSTREAM. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

Context view, looking southwest along the WelltonMohawk Canal. The wasteway ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Context view, looking southwest along the Wellton-Mohawk Canal. The wasteway is marked by the white posts on either side of the access road. The pipe across the canal safely carries storm runoff over the canal and is not part of Wasteway No. 1 - Wellton-Mohawk Irrigation System, Wasteway No. 1, Wellton-Mohawk Canal, North side of Wellton-Mohawk Canal, bounded by Gila River to North & the Union Pacific Railroad & Gila Mountains to south, Wellton, Yuma County, AZ

22. TWIN FALLS MAIN CANAL HEADWORKS WITH MILNER DAM IN ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

22. TWIN FALLS MAIN CANAL HEADWORKS WITH MILNER DAM IN DISTANCE; LOOKING EAST. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

23. TWIN FALLS MAIN CANAL HEADWORKS WITH MILNER DAM IN ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

23. TWIN FALLS MAIN CANAL HEADWORKS WITH MILNER DAM IN DISTANCE; LOOKING NORTHEAST. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

Technology, the Potomac Canal, and National Unity.

ERIC Educational Resources Information Center

Keller, Clair W.

1989-01-01

Illustrates the relationship between the technology of canal building and the development of national unity prior to the Revolutionary War. Examines George Washington's efforts to build the Potomac canal. Encourages students to consider the interrelationships among technology, resources, politics, and leadership. Includes two student handouts and…

33 CFR 117.495 - Superior Oil Canal.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Superior Oil Canal. 117.495 Section 117.495 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Louisiana § 117.495 Superior Oil Canal. The draw of...

33 CFR 117.495 - Superior Oil Canal.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Superior Oil Canal. 117.495 Section 117.495 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Louisiana § 117.495 Superior Oil Canal. The draw of...

33 CFR 117.495 - Superior Oil Canal.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Superior Oil Canal. 117.495 Section 117.495 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Louisiana § 117.495 Superior Oil Canal. The draw of...

31. MAIN CANAL Photographic copy of historic photo, December ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

31. MAIN CANAL - Photographic copy of historic photo, December 13, 1939 (original print in '1939 Annual Report of the Carlsbad Project,' located at the Carlsbad Irrigation District offices, Carlsbad, New Mexico) photographer unknown 'LINING MAIN CANAL AROUND GYP BEND' - Carlsbad Irrigation District, Main Canal, 4 miles North to 12 miles Southeast of Carlsbad, Carlsbad, Eddy County, NM

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

USGS Publications Warehouse

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

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

PubMed

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). There was no significant difference between NiTi rotary system groups at any levels (P > .05) except 2.5 mm from the WL. At this level ProTaper Universal system caused significant canal transportation (P < .05). GT Series X and Twisted File rotary systems produced with innovative process were concluded to shape the curved canals to result in minimal canal transportation, similar to Revo-S, RaCe, Mtwo, and ProTaper Universal rotary systems manufactured by traditional methods. Copyright © 2013 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Maxillary First Molars with 2 Distobuccal Canals: A Case Series.

PubMed

Fogel, Howard M; Cunha, Rodrigo Sanches

2017-11-01

An appreciation of the anatomic complexity of the root canal system is essential at every step of endodontic treatment. Endodontic treatment of teeth with unusual root canal anatomy presents a unique challenge. Eight patients underwent nonsurgical root canal treatment of 3-rooted maxillary first molars in a specialty endodontic private practice. Four cases of Weine type II and 4 cases of Weine type III canal configurations in the distobuccal root of maxillary first molars were presented.This article highlighted an uncommon anatomic variation of 2 canals in the distobuccal root of the maxillary first molar. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

6. View southwest, culvert inlet with canal bank completely removed. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

6. View southwest, culvert inlet with canal bank completely removed. Left to right: back of headwall; tops of high inlet barrels; vertical transition wall between high inlet barrels and low, interior, inlet barrels; tops of low interior barrels; vertical heartening planks and low cutoff wall along former edge of canal bank; dewatered canal bed. - Delaware & Raritan Canal, Ten Mile Run Culvert, 1.5 miles South of Blackwells Road, East Millstone, Somerset County, NJ

148. TWIN FALLS MAIN CANAL DIVERSION, TWIN FALLS COUNTY, MILNER ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

148. TWIN FALLS MAIN CANAL DIVERSION, TWIN FALLS COUNTY, MILNER DAM; HEADGATES AT INLET, SOUTHWEST VIEW. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

98. SHOESTRING, TWIN FALLS MAIN CANAL, TWIN FALLS COUNTY NORTHWEST ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

98. SHOESTRING, TWIN FALLS MAIN CANAL, TWIN FALLS COUNTY NORTHWEST OF MURTAUGH, IDAHO; PROFILE VIEW, SOUTH. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

16. VIEW OF HIGHLINE CANAL PIPELINE OUTLET, SHOWING THE OUTLET, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

16. VIEW OF HIGHLINE CANAL PIPELINE OUTLET, SHOWING THE OUTLET, A GROUNDWATER PUMP (LEFT), AND THE SOUTH BRANCH OF THE CANAL (FOREGROUND), August 1989 - Highline Canal & Pumping Station, South side of Salt River between Tempe, Phoenix & Mesa, Tempe, Maricopa County, AZ

Cutaneous Sinus Tract from Mandibular Second Molar with C-shaped Canal System and Improper Former Root Canal Treatment: A Case Report.

PubMed

Gharechahi, Maryam; Dastmalchi, Parisa

2016-01-01

Here, we report the diagnosis and treatment of an extraoral cutaneous sinus tract originating in a mandibular second molar with a C-shaped root canal system. The patient was referred to our department by a dermatologist after a series of unsuccessful treatments, including antibiotics. Diffuse radiolucency on a preoperative radiograph revealed that earlier root canal treatment had been only partially successful. Consequently, we performed retreatment of the root canal comprising removal of the former restoration and gutta-percha, cleaning and shaping, and passive irrigation with sodium hypochlorite. The patient responded well, and the cutaneous lesion completely resolved uneventfully within 1 month postoperatively. Preoperative recognition and thorough knowledge of the root canal anatomy and conventional methods of obturation are necessary in performing successful endodontic treatment.

33 CFR 117.769 - Black Rock Canal.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Black Rock Canal. 117.769 Section 117.769 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements New York § 117.769 Black Rock Canal. The draws of the...

33 CFR 117.769 - Black Rock Canal.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Black Rock Canal. 117.769 Section 117.769 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements New York § 117.769 Black Rock Canal. The draws of the...

33 CFR 117.769 - Black Rock Canal.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Black Rock Canal. 117.769 Section 117.769 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements New York § 117.769 Black Rock Canal. The draws of the...

33 CFR 117.769 - Black Rock Canal.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Black Rock Canal. 117.769 Section 117.769 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements New York § 117.769 Black Rock Canal. The draws of the...

33 CFR 117.769 - Black Rock Canal.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Black Rock Canal. 117.769 Section 117.769 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements New York § 117.769 Black Rock Canal. The draws of the...

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

Code of Federal Regulations, 2010 CFR

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...

ASTER Suez Canal

NASA Technical Reports Server (NTRS)

2000-01-01

One of the most important waterways in the world, the Suez Canal runs north to south across the Isthmus of Suez in northeastern Egypt. This image of the canal covers an area 36 kilometers (22 miles) wide and 60 kilometers (47 miles) long in three bands of the reflected visible and infrared wavelength region. It shows the northern part of the canal, with the Mediterranean Sea just visible in the upper right corner. The Suez Canal connects the Mediterranean Sea with the Gulf of Suez, an arm of the Red Sea. The artificial canal provides an important shortcut for ships operating between both European and American ports and ports located in southern Asia, eastern Africa, and Oceania. With a length of about 195 kilometers (121 miles) and a minimum channel width of 60 meters (197 feet), the Suez Canal is able to accommodate ships as large as 150,000 tons fully loaded. Because no locks interrupt traffic on this sea level waterway, the transit time only averages about 15 hours. ASTER acquired this scene on May 19, 2000.

Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of International Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, California, is the U.S. science team leader; Moshe Pniel of JPL is the project manager. ASTER is the only high-resolution imaging sensor on Terra. The primary goal of the ASTER mission is to obtain high-resolution image data in 14 channels over the entire land surface, as well as black and white stereo images. With revisit time of between 4 and 16 days, ASTER will provide the capability for repeat coverage of changing areas on Earth's surface. Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is one of five

109. CEDAR DRAW SPILL, LOW LINE CANAL, TWIN FALLS COUNTY, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

109. CEDAR DRAW SPILL, LOW LINE CANAL, TWIN FALLS COUNTY, SOUTH OF FILER, IDAHO; OVERALL VIEW LOOKING WEST. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

95. CEDAR DRAW SPILL, LOW LINE CANAL, TWIN FALLS COUNTY ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

95. CEDAR DRAW SPILL, LOW LINE CANAL, TWIN FALLS COUNTY SOUTH OF FILER, IDAHO; OVERALL VIEW LOOKING EAST. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

110. ROCK CREEK SIPHON, LOW LINE CANAL, TWIN FALLS COUNTY, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

110. ROCK CREEK SIPHON, LOW LINE CANAL, TWIN FALLS COUNTY, SOUTH OF KIMBERLY, IDAHO; INLET SIDE WEST VIEW. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

90. CEDAR DRAW SPILL, HIGH LINE CANAL, TWIN FALLS COUNTY, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

90. CEDAR DRAW SPILL, HIGH LINE CANAL, TWIN FALLS COUNTY, SOUTH OF FILER, IDAHO; CLOSE-UP OF GATES. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

112. ROCK CREEK SIPHON LOW LINE CANAL, TWIN FALLS COUNTY, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

112. ROCK CREEK SIPHON LOW LINE CANAL, TWIN FALLS COUNTY, SOUTH OF KIMBERLY IDAHO; OUTLET SIDE, EAST VIEW. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

93. ROCK CREEK SIPHON, LOW LINE CANAL, TWIN FALLS COUNTY ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

93. ROCK CREEK SIPHON, LOW LINE CANAL, TWIN FALLS COUNTY SOUTH OF KIMBERLY, IDAHO; OVERALL NORTHEAST VIEW. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

147. TWIN FALLS MAIN CANAL DIVERSION, TWIN FALLS COUNTY, MILNER, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

147. TWIN FALLS MAIN CANAL DIVERSION, TWIN FALLS COUNTY, MILNER, IDAHO; VIEW OF MAIN HEADGATES, EAST VIEW. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

124. MCMULLEN CREEK HIGH LINE CANAL, TWIN FALLS COUNTY, SOUTH ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

124. MCMULLEN CREEK HIGH LINE CANAL, TWIN FALLS COUNTY, SOUTH OF KIMBERLY, IDAHO; OVERALL SOUTH VIEW OF DRAW. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

188. Photocopy of drawing, Twin Falls Canal Company, date unknown. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

188. Photocopy of drawing, Twin Falls Canal Company, date unknown. DETAILS OF GATE RAISING MECHANISM, NO COUNTY; BLUEPRINT. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

30. MAIN CANAL Photographic copy of historic photo, January ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

30. MAIN CANAL - Photographic copy of historic photo, January 29, 1907 (original print filed in Record Group 115, National Archives, Washington, D.C.) W.J.Lubken, photographer 'CHECK GATES ON SOUTHERN CANAL, STA.118, JUST ABOVE THE ENTRANCE END OF DARK CANYON PRESSURE PIPE' - Carlsbad Irrigation District, Main Canal, 4 miles North to 12 miles Southeast of Carlsbad, Carlsbad, Eddy County, NM

Laser Application in Dentistry: Irradiation Effects of Nd:YAG 1064 nm and Diode 810 nm and 980 nm in Infected Root Canals-A Literature Overview.

PubMed

Saydjari, Yves; Kuypers, Thorsten; Gutknecht, Norbert

2016-01-01

Objective. In endodontics, Nd:YAG laser (1064 nm) and diode laser (810 nm and 980 nm) devices are used to remove bacteria in infected teeth. A literature review was elaborated to compare and evaluate the advantages and disadvantages of using these lasers. Methods. Using combined search terms, eligible articles were retrieved from PubMed and printed journals. The initial search yielded 40 titles and 27 articles were assigned to full-text analysis. The studies were classified based upon laser source, laser energy level, duration/similarity of application, and initial and final bacterial count at a minimum of 20 prepared root canals. Part of the analysis was only reduced microorganisms and mechanically treated root canals upon preparation size of ISO 30. All studies were compared to evaluate the most favorable laser device for best results in endodontic therapy. Results. A total of 22 eligible studies were found regarding Nd:YAG laser 1064 nm. Four studies fulfilled all demanded criteria. Seven studies referring to the diode laser 980 nm were examined, although only one fulfilled all criteria. Eleven studies were found regarding the diode laser 810 nm, although only one study fulfilled all necessary criteria. Conclusions. Laser therapy is effective in endodontics, although a comparison of efficiency between the laser devices is not possible at present due to different study designs, materials, and equipment.

13. VIEW OF WESTERN CANAL EAST OF CARRIAGE LANE IN ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

13. VIEW OF WESTERN CANAL EAST OF CARRIAGE LANE IN TEMPE, SHOWING DROP STRUCTURE AND GROUNDWATER PUMP. THIS IS THE LAST OF FOUR PUMPS WHICH FEED DIRECTLY INTO THE CANAL BETWEEN ALMA SCHOOL ROAD AND PRICE ROAD. ON THIS DAY, ALL FOUR PUMPS, OPERATING AT FULL OUTPUT, HAVE CONSIDERABLY SWELLED THE FLOW TO THE CANAL. NOTE THE OLD FASHIONED BRICKWORK ON THE NORTH BANK. - Western Canal, South side of Salt River between Tempe, Phoenix & Mesa, Mesa, Maricopa County, AZ

Posterior semicircular canal dehiscence: value of VEMP and multidetector CT.

PubMed

Vanspauwen, R; Salembier, L; Van den Hauwe, L; Parizel, P; Wuyts, F L; Van de Heyning, P H

2006-01-01

To illustrate that posterior semicircular canal dehiscence can present similarly to superior semicircular canal dehiscence. The symptomatology initially presented as probable Menière's disease evolving into a mixed conductive hearing loss with a Carhart notch-type perceptive component suggestive of otosclerosis-type stapes fixation. A small hole stapedotomy resulted in a dead ear and a horizontal semicircular canal hypofunction. Recurrent incapacitating vertigo attacks developed. Vestibular evoked myogenic potential (VEMP) testing demonstrated intact vestibulocollic reflexes. Additional evaluation with high resolution multidetector computed tomography (MDCT) of the temporal bone showed a dehiscence of the left posterior semicircular canal. Besides superior semicircular canal dehiscence, posterior semicircular canal dehiscence has to be included in the differential diagnosis of atypical Menière's disease and/or low tone conductive hearing loss. The value of performing MDCT before otosclerosis-type surgery is stressed. VEMP might contribute to establishing the differential diagnosis.

Root Canal Microbiota of Teeth with Chronic Apical Periodontitis▿ †

PubMed Central

Rôças, I. N.; Siqueira, J. F.

2008-01-01

Samples from infected root canals of 43 teeth with chronic apical periodontitis were analyzed for the presence and relative levels of 83 oral bacterial species and/or phylotypes using a reverse-capture checkerboard hybridization assay. Associations between the most frequently detected taxa were also recorded. The most prevalent taxa were Olsenella uli (74%), Eikenella corrodens (63%), Porphyromonas endodontalis (56%), Peptostreptococcus anaerobius (54%), and Bacteroidetes oral clone X083 (51%). When prevalence was considered only for bacteria present at levels >105, Bacteroidetes clone X083 was the most frequently isolated bacterium (37%), followed by Parvimonas micra (28%), E. corrodens (23%), and Tannerella forsythia (19%). The number of target taxa per canal was directly proportional to the size of the apical periodontitis lesion, with lesions >10 mm in diameter harboring a mean number of approximately 20 taxa. Several positive associations for the most prevalent taxa were disclosed for the first time and may have important ecological and pathogenic implications. In addition to strengthening the association of several cultivable named species with chronic apical periodontitis, the present findings using a large-scale analysis allowed the inclusion of some newly named species and as-yet-uncultivated phylotypes in the set of candidate pathogens associated with this disease. PMID:18768651

197. Photocopy of drawing, Twin Falls, Canal Company, date unknown. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

197. Photocopy of drawing, Twin Falls, Canal Company, date unknown. GATE STEMS AND LIFTING DEVICES, NO COUNTY; BLUEPRINT SKETCHES. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

193. Photocopy of Photograph, Twin Falls Canal Company, date unknown. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

193. Photocopy of Photograph, Twin Falls Canal Company, date unknown. MILNER DAM PROFILE, TWIN FALLS COUNTY, MILNER, IDAHO; BLUEPRINT. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

186. Photocopy of drawing, Twin Falls Canal Company, date unknown. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

186. Photocopy of drawing, Twin Falls Canal Company, date unknown. DRY CREEK RESERVOIR, CASSIA COUNTY (NOW TWIN FALLS COUNTY); MAP. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

114. ROCK CREEK SIPHON LOW LINE CANAL, TWIN FALLS COUNTY, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

114. ROCK CREEK SIPHON LOW LINE CANAL, TWIN FALLS COUNTY, SOUTH OF KIMBERLY IDAHO; OVERALL VIEW, WEST OF INLET SIDE. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

111. ROCK CREEK SIPHON LOW LINE CANAL, TWIN FALLS COUNTY, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

111. ROCK CREEK SIPHON LOW LINE CANAL, TWIN FALLS COUNTY, SOUTH OF KIMBERLY IDAHO; OVERALL VIEW OF SIPHON, EAST VIEW. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

191. Photocopy of drawing, Twin Falls Canal Company, date unknown. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

191. Photocopy of drawing, Twin Falls Canal Company, date unknown. SPILLWAY GATES, MILNER DAM, TWIN FALLS COUNTY, MILNER, IDAHO; BLUEPRINT. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

181. Photocopy of Photograph, Twin Falls Canal Company. Photographer and ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

181. Photocopy of Photograph, Twin Falls Canal Company. Photographer and date unknown. POINT SPILL, TWIN FALLS COUNTY; SOUTH VIEW. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

47. FEEDER CANAL AT WILL'S BASIN. BOATS IN THE FOREGROUND ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

47. FEEDER CANAL AT WILL'S BASIN. BOATS IN THE FOREGROUND SHOW THE CONTRAST BETWEEN A FULLY LOADED CANAL BOAT (LEFT) AND AN EMPTY ONE (RIGHT). D, L & W RAILROAD'S DOUBLE INTERSECTION PRATT TRUSS BRIDGE IS VISIBLE IN BACKGROUND. - Morris Canal, Phillipsburg, Warren County, NJ

70. GENERAL VIEW OF CANAL IN DOVER LOOKING EAST. WHAT ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

70. GENERAL VIEW OF CANAL IN DOVER LOOKING EAST. WHAT APPEARS TO BE A SWING BRIDGE IS VISIBLE ACROSS CANAL ON RIGHT SIDE OF PHOTOGRAPH (NOTE THAT THIS MAY ALSO BE A LIFT BRIDGE WITH THE LIFT EQUIPMENT REMOVED). - Morris Canal, Phillipsburg, Warren County, NJ

Comparison of efficacy of pulverization and sterile paper point techniques for sampling root canals.

PubMed

Tran, Kenny T; Torabinejad, Mahmoud; Shabahang, Shahrokh; Retamozo, Bonnie; Aprecio, Raydolfo M; Chen, Jung-Wei

2013-08-01

The purpose of this study was to compare the efficacy of the pulverization and sterile paper point techniques for sampling root canals using 5.25% NaOCl/17% EDTA and 1.3% NaOCl/MTAD (Dentsply, Tulsa, OK) as irrigation regimens. Single-canal extracted human teeth were decoronated and infected with Enterococcus faecalis. Roots were randomly assigned to 2 irrigation regimens: group A with 5.25% NaOCl/17% EDTA (n = 30) and group B with 1.3% NaOCl/MTAD (n = 30). After chemomechanical debridement, bacterial samplings were taken using sterile paper points and pulverized powder of the apical 5 mm root ends. The sterile paper point technique did not show growth in any samples. The pulverization technique showed growth in 24 of the 60 samples. The Fisher exact test showed significant differences between sampling techniques (P < .001). The sterile paper point technique showed no difference between irrigation regimens. However, 17 of the 30 roots in group A and 7 of the 30 roots in group B resulted in growth as detected by pulverization technique. Data showed a significant difference between irrigation regimens (P = .03) in pulverization technique. The pulverization technique was more efficacious in detecting viable bacteria. Furthermore, this technique showed that 1.3% NaOCl/MTAD regimen was more effective in disinfecting root canals. Published by Elsevier Inc.

Three rooted, four canalled mandibular first molar (Radix Entomolaris).

PubMed

Parolia, Abhishek; Kundabala, M; Thomas, M S; Mohan, M; Joshi, N

2009-01-01

A mandibular first molar with two distal roots is an interesting example of anatomic variation. This paper describes case reports of mandibular first molar with three roots (one mesial and two distal) and four canals (two in mesial and one in each distobuccal and distolingual root). The canals were shaped with protaper rotary files and irrigated with 5.25% sodium hyochlorite, 0.2 %w/v of chlorhexidine gluconate and normal saline as the fi nal irrigant. The canals were then obturated with gutta- percha and AH plus sealer. These case reports show an anatomic variation of internal morphology of the tooth and points out the importance of searching for additional canals.

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

PubMed

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.

185. Photocopy of drawing, Twin Falls Canal Company, date unknown. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

185. Photocopy of drawing, Twin Falls Canal Company, date unknown. MILNER DAM CROSS SECTION PLAN, TWIN FALLS COUNTY, MILNER, IDAHO; BLUEPRINT. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

115. ROCK CREEK SIPHON LOW LINE CANAL, TWIN FALLS COUNTY, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

115. ROCK CREEK SIPHON LOW LINE CANAL, TWIN FALLS COUNTY, SOUTH OF KIMBERLY IDAHO; WEST VIEW OF SIPHON CROSSING ROCK CREEK. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

96. CEDAR DRAW SPILL, LOW LINE CANAL, TWIN FALLS COUNTY ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

96. CEDAR DRAW SPILL, LOW LINE CANAL, TWIN FALLS COUNTY SOUTH OF FILER, IDAHO; OUTLET SIDE OF CEDAR DRAW, WEST VIEW. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

195. Photocopy of drawing, Twin Falls Canal Company, date unknown. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

195. Photocopy of drawing, Twin Falls Canal Company, date unknown. PLAN OF CONSTRUCTION AREA PLANT, TWIN FALLS COUNTY, MILNER, IDAHO; BLUEPRINT. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

141. TWIN FALLS MAIN CANAL DIVERSION, TWIN FALLS COUNTY, MILNER, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

141. TWIN FALLS MAIN CANAL DIVERSION, TWIN FALLS COUNTY, MILNER, IDAHO; CLOSE-UP OF MAIN HEADGATES, RADIAL GATES INSIDE, SOUTHEAST VIEW. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

137. TWIN FALLS SOUTH SIDE MAIN CANAL DIVERSION HEADGATES, TWIN ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

137. TWIN FALLS SOUTH SIDE MAIN CANAL DIVERSION HEADGATES, TWIN FALLS COUNTY, MILNER, IDAHO; OVERALL VIEW OF MAIN HEADGATES, DAM IN BACKGROUND. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

190. Photocopy of drawing, Twin Falls Canal Company, date unknown. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

190. Photocopy of drawing, Twin Falls Canal Company, date unknown. GENERAL PLAN OF MILNER DAM TUNNELS, TWIN FALLS COUNTY, MILNER, IDAHO; BLUEPRINT. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

5 CFR 315.601 - Appointment of former employees of the Canal Zone Merit System or Panama Canal Employment System.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Appointment of former employees of the Canal Zone Merit System or Panama Canal Employment System. 315.601 Section 315.601 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS CAREER AND CAREER-CONDITIONAL EMPLOYMENT Career or Career-Conditional Appointment Unde...

Report from the Panama Canal Stakeholder Working Group.

DOT National Transportation Integrated Search

2013-03-01

This project assists the Texas Department of Transportation (TxDOT) in assessing the potential impacts of the Panama Canal expansion on Texas ports and the landside transportation system. TxDOT formed a Panama Canal Stakeholder Working Group (PCSWG) ...

25. TWIN FALLS MAIN CANAL HEADWORKS FROM UPSTREAM LOOKING TOWARD ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

25. TWIN FALLS MAIN CANAL HEADWORKS FROM UPSTREAM LOOKING TOWARD THE WEST (DAM-TENDER RICHARD CARL ADJUSTING THE GATES TO ALLOW 3400 CFS THROUGH). - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

156. Photocopy of written record (taken from Twin Falls Canal ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

156. Photocopy of written record (taken from Twin Falls Canal Company, Low Line Book #1, pp.2,3). LOW LINE CONTRACTORS AND BORROW RECORD. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

113. ROCK CREEK SIPHON LOW LINE CANAL, TWIN FALLS COUNTY, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

113. ROCK CREEK SIPHON LOW LINE CANAL, TWIN FALLS COUNTY, SOUTH OF KIMBERLY IDAHO; CLOSE-UP OF INLET SIDE OF SIPHON, NORTHWEST VIEW. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

99. POINT SPILL, TWIN FALLS MAIN CANAL, TWIN FALLS COUNTY ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

99. POINT SPILL, TWIN FALLS MAIN CANAL, TWIN FALLS COUNTY NORTHWEST OF MURTAUGH, IDAHO; CLOSE-UP OF OUTLET SIDE OF GATES, SOUTH VIEW. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

116. ROCK CREEK SIPHON LOW LINE CANAL, TWIN FALLS COUNTY, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

116. ROCK CREEK SIPHON LOW LINE CANAL, TWIN FALLS COUNTY, SOUTH OF KIMBERLY IDAHO; CLOSE-UP OF OUTLET, DIVERSION SPILL IN BACKGROUND, WEST VIEW. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

182. Photocopy of Photograph, Twin Falls Canal Company. Photographer and ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

182. Photocopy of Photograph, Twin Falls Canal Company. Photographer and date unknown. MILNER DAM TUNNELS, TWIN FALLS COUNTY, MILNER, IDAHO; APPROACH TO TUNNELS. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

92. CEDAR DRAW SPILL, HIGH LINE CANAL, TWIN FALLS COUNTY ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

92. CEDAR DRAW SPILL, HIGH LINE CANAL, TWIN FALLS COUNTY SOUTH OF FILER, IDAHO; CLOSE-UP OF OUTLET SIDE OF GATES, SOUTH VIEW. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

187. Photocopy of drawing, Twin Falls Canal Company, date unknown. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

187. Photocopy of drawing, Twin Falls Canal Company, date unknown. TOPOGRAPHICAL MAP OF MILNER DAM LOCATION, TWIN FALLS COUNTY, MILNER, IDAHO; BLUEPRINT MAP. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

133. FORKS DIVERSION, HIGH LINE AND LOW LINE CANALS, TWIN ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

133. FORKS DIVERSION, HIGH LINE AND LOW LINE CANALS, TWIN FALLS COUNTY, SOUTH OF HANSEN, IDAHO; VIEW OF OUTLET SIDE OF LOW LINE GATES. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

12. VIEW OF WESTERN CANAL AT ALMA SCHOOL ROAD IN ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

12. VIEW OF WESTERN CANAL AT ALMA SCHOOL ROAD IN MESA, THE LOCATION AT WHICH THE PECK, PINE AND WALLACE FEEDERS FORMERLY JOINED TO FORM THE WESTERN CANAL. THE PECK AND PINE FEEDERS, NOW KNOWN AS LATERAL 9 AND LATERAL 10, AND ALMOST ENTIRELY PIPED, STILL JOIN THE WESTERN CANAL AT THIS POINT, BUT AN EQUALLY IMPORTANT SOURCE OF SUPPLY IS THE NUMEROUS GROUNDWATER PUMPS LOCATED ON THE SYSTEM. - Western Canal, South side of Salt River between Tempe, Phoenix & Mesa, Mesa, Maricopa County, AZ

Morphometric study of the lumbar spinal canal in the Korean population.

PubMed

Lee, H M; Kim, N H; Kim, H J; Chung, I H

1995-08-01

The anatomic dimensions of the vertebral body and spinal canal of the lumbar spine were analyzed in Koreans. To determine the normal dimension of the lumbar spinal canal in Koreans, to determine whether there are any racial differences in the morphometry of the lumbar spinal canal, and to provide criteria for diagnosing spinal stenosis in the Far Eastern Asian. Some radiologic and anatomic studies have been conducted regarding the size of the lumbar spinal canal of whites and blacks in western and African countries. One-thousand-eight-hundred measurements were performed on the transverse and sagittal diameters of vertebral bodies and spinal canals using complete sets of 90 lumbar vertebrae. The mean mid-sagittal diameter of the lumbar spinal canal in the Korean population was less than that measured in white and African populations, but there was no significant differences between the Korean, white, and African populations regarding the transverse diameter of the lumbar spinal canal. The mid-sagittal diameter of the lumbar spinal canal is narrowest in the Far Eastern Asian population; the radiologic criteria of spinal stenosis should be reconsidered for these people.

Root canal debridement: an online study guide.

PubMed

2008-05-01

The Editorial Board of the Journal of Endodontics has developed a literature-based study guide of topical areas related to endodontics. This study guide is intended to give the reader a focused review of the essential endodontic literature and does not cite all possible articles related to each topic. Although citing all articles would be comprehensive, it would defeat the idea of a study guide. This section will present root canal debridement including subdivisions on canal access, canal debridement, orifice enlargement and preflaring, crown-down technique, balanced force, nickel titanium and other shape memory alloys, rotary engine-driven techniques, endodontic instruments, irrigation, electronic apex locators, sonics/ultrasonics, smear layer, and intracanal medicaments.

Decision tree analysis to evaluate dry cow strategies under UK conditions.

PubMed

Berry, Elizabeth A; Hogeveen, Henk; Hillerton, J Eric

2004-11-01

Economic decisions on animal health strategies address the cost-benefit aspect along with animal welfare and public health concerns. Decision tree analysis at an individual cow level highlighted that there is little economic difference between the use of either dry cow antibiotic or an internal teat sealant in preventing a new intramammary infection in a cow free of infection in all quarters of the mammary gland at drying off. However, a potential net loss of over ł20 per cow might occur if the uninfected cow was left untreated. The only economically viable option, for a cow with one or more quarters infected at drying off, is antibiotic treatment, although a loss might still be incurred depending on the pathogen concerned and the cure rates achievable. There was a net loss for cows with quarters infected with Corynebacterium spp. at drying off, for both the teat sealant and untreated groups (ł22 and ł48, respectively) with only antibiotic-treated cows showing a gain.

10. EAST SIDE CANAL Photographic copy of historic photo, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

10. EAST SIDE CANAL - Photographic copy of historic photo, December 3, 1940 (original print in '1940 Annual Report of the Carlsbad Project,' located at the Carlsbad Irrigation District offices, Carlsbad, New Mexico) photographer unknown 'LOOKING DOWN FROM STA. #22 LATERAL #8, EAST CANAL. AFTER CCC ENROLLEES FINISHED ROCK LINING' - Carlsbad Irrigation District, East Side Canal, 1 mile North to 2 miles East of Carlsbad, Carlsbad, Eddy County, NM

9. EAST SIDE CANAL Photographic copy of historic photo, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

9. EAST SIDE CANAL - Photographic copy of historic photo, September 17, 1940 (original print in '1940 Annual Report of the Carlsbad Project,' located at the Carlsbad Irrigation District offices, Carlsbad, New Mexico) photographer unknown 'CCC ENROLLEES STARTING EXCAVATION FOR ROCK LINING DOWNSTREAM FROM STA. 22. EAST CANAL, LAT. #8' - Carlsbad Irrigation District, East Side Canal, 1 mile North to 2 miles East of Carlsbad, Carlsbad, Eddy County, NM

159. Photocopy of written record (taken from Twin Falls Canal ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

159. Photocopy of written record (taken from Twin Falls Canal Company Low Line Book #1, pp. 76,77). RECORD OF BORROW AT LOW LINE SIPHON. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

194. Photocopy of drawing, Twin Falls Canal Company, date unknown. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

194. Photocopy of drawing, Twin Falls Canal Company, date unknown. PROFILE AND GATE PLAN, NORTH ISLAND CROSS SECTION OF DAM, TWIN FALLS COUNTY, MILNER, IDAHO; BLUEPRINT. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

130. FORKS DIVERSION, HIGH LINE AND LOW LINE CANALS, TWIN ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

130. FORKS DIVERSION, HIGH LINE AND LOW LINE CANALS, TWIN FALLS COUNTY, SOUTH OF HANSEN, IDAHO; OUTLET SIDE OF THE HIGH LINE GATES, NORTH VIEW. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

33 CFR 117.661 - Duluth Ship Canal (Duluth-Superior Harbor).

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Duluth Ship Canal (Duluth-Superior Harbor). 117.661 Section 117.661 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF... Ship Canal (Duluth-Superior Harbor). The draw of the Duluth Ship Canal Aerial bridge, mile 0.25 at...

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

PubMed

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.

[The development and in vitro experiment study of a bio-type root canal filling sealer using calcium phosphate cement].

PubMed

Chen, Zuo-liang; Wei, Wei; Feng, Zhu-de; Liu, Xue-qing; Chen, Xiao-ling; Huang, Wen-xia

2007-10-01

The purpose of this study is to develop a novel root canal filling sealers based on calcium phosphate cement (CPC), and to evaluate its physical-chemical properties and in vitro antibacterial activity on the predominant bacteria infecting root canal. The fluidity and the setting time of the sealer were tested according to ISO 6876:2001(E) standards. The crystal size of the final product was determined. Its opacification with different composition were measured. The in vitro antibacterial property of the sealer was tested according to the Antimicrobial Susceptibility Testing of Anaerobes recommended by National Committee for Clinical Laboratory Standards (NCCLs). The involved bacteria included Actinomyces naeslundii(A. naeslundii), Peptostreptococcus anaerobius (P. anaerobius), Porphyromonas gingivalis (P. gingivalis), Porphyromonas endodpntalis (P. endodpntalis) and Fusobacterium nucleatum (F. nucleatum). Twenty single-rooted human extracted teeth were selected to evaluate the sealing ability using dye microleakage technology. Dye penetration was measured and the results were statistically analyzed using SPSS12.0 software package. The new root canal filling sealer was primarily composed of hydroxyapatite in 279 nm after setting. Its liquidity was suitable, the operating time was over 30 minutes, and the controlled setting time was (1.0+/-0.5) hours. The opacification was acceptable. MICcanal filling sealer is an ideal root canal filling sealer. Supported by Science and Technology Development Fund from the Science and Technology Bureau of Xiamen City (Grant No.2002-60-5).

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

NASA Astrophysics Data System (ADS)

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

Trematode infections in pregnant ewes can predispose to mastitis during the subsequent lactation period.

PubMed

Mavrogianni, V S; Papadopoulos, E; Spanos, S A; Mitsoura, A; Ptochos, S; Gougoulis, D A; Barbagianni, M S; Kyriazakis, I; Fthenakis, G C

2014-02-01

Objective was to investigate if trematode infections predispose ewes to mastitis and/or metritis. We used 80 trematode-infected ewes: primigravidae in group P-A and multigravidae in M-A remained untreated, primigravidae in P-B and multigravidae in M-B were drenched with netobimin and multigravidae in M-C were given rafoxanide. We collected faecal samples for parasitological examination, blood samples for β-hydroxybutyrate concentration measurement and uterine content, teat duct material and milk samples for bacteriological examination. We found significant differences in blood β-hydroxybutyrate concentrations between M-A, M-B and M-C during pregnancy (P ⩽ 0.002). We did not observe significant differences between groups regarding development of metritis (P>0.83). We found that for M-A, M-B and M-C ewes, respectively, median time to first case of mastitis was 5.75, 21 and 6.75 days after lambing (P = 0.003) and incidence risk of mastitis was 0.308, 0.069 and 0.222 (P = 0.047). We postulate that trematode infections predispose ewes to mastitis; perhaps, increased β-hydroxybutyrate blood concentrations adversely affect mammary cellular defences. This is the first report associating parasitic infections with mastitis in sheep. Copyright © 2013 Elsevier Ltd. All rights reserved.

Undergraduate students introduction to manual and rotary root canal instrumentation.

PubMed

Leonardi, Denise Piotto; Haragushiku, Gisele Aihara; Tomazinho, Flavia Sens Fagundes; Furuse, Adilson Yoshio; Volpato, Lusiane; Baratto-Filho, Flares

2012-01-01

The aim of this study was to evaluate the performance of undergraduates in their first contact with manual and rotary root canal instrumentation. Forty-two students who had never worked on a root canal before instrumented 42 extracted lower-incisors. Participants were assigned to one of two groups: Rotary instrumentation or manual instrumentation. Pre- and post-operative computed tomography scans were obtained with a 3-dimensional dental imaging system. Starting and finishing times of preparation were recorded. The cross-sectional area of the root canal was analyzed with 2-mm-below-the-apex initial and final transverse images recorded through a digital imaging system and analyzed with software to measure the initial and final area of the root canal in mm(2). Data from the cross-sectional area of the root canal and time spent were subjected to the Mann-Whitney's U-test (p<0.05). The rotary instrumentation group showed smaller time for preparation (p=0.0204). No differences between rotary and manual instrumentation regarding the cross-sectional area of the root canal were observed (p=0.25). No accidents occurred. Undergraduate students showed good performance in their first contact with the manual and rotary instrumentation with regard to time spent and cross-sectional area of the root canal, with no operative accidents.

Root canal preparation in endodontics: conventional versus laser methods

NASA Astrophysics Data System (ADS)

Goodis, Harold E.; White, Joel M.; Marshall, Sally J.; Marshall, Grayson W.; Moskowitz, Emrey

1992-06-01

Conventional cleaning and shaping of root canal systems employs hand and/or rotary instrumentation to remove the contents of the canal and shape the canal to receive a filling material. With the advent of the Nd:YAG laser system another method of accomplishing proper cleaning and shaping is evaluated. Single rooted teeth were radiographed bucco- lingually and mesio-distally and were divided into 2 groups. The first group was accessed and the root canal systems cleaned and shaped with a step back technique utilizing hand files and gates glidden burs. At completion of the procedure the teeth were again radiographed at the same positions as those prior to the procedure. The teeth were split longitudinally and examined under scanning electron microscopy to assess cleaning. The second group of teeth were accessed, and cleaning and shaping was accomplished using the Nd:YAG laser in combination with hand files and rotary instruments. These teeth were subjected to the same analysis as those in the first group. The before and after radiographs of each group were subjected to image analysis to determine effectiveness of the two methods in shaping the canal systems. We will discuss the ability of Nd:YAG to clean and shape root canal spaces and remove smear layer and organic tissue remnants from those areas.

152. Photocopy of drawing (taken from Twin Falls Canal Company ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

152. Photocopy of drawing (taken from Twin Falls Canal Company Surveyor's Transit Book #363, Page 1). 1912 CONDITION REPORT OF MILNER DAM AREA, TWIN FALLS COUNTY, MILNER, IDAHO. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

183. Photocopy of map (Twin Falls Canal Company). TOPOGRAPHICAL MAP ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

183. Photocopy of map (Twin Falls Canal Company). TOPOGRAPHICAL MAP OF MILNER DAM SITE, TWIN FALLS COUNTY, MILNER, IDAHO; MAP, LEFT SIDE ONLY. CROSS REFERENCE: ID-15-192. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

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

PubMed Central

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

2017-01-01

Context and Aims: 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. Materials and Methods: 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. Results: 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. Conclusions: 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. PMID:28855757

ROUTING DEMAND CHANGES TO USERS ON THE WM LATERAL CANAL WITH SACMAN

USDA-ARS?s Scientific Manuscript database

Most canals have either long travel times or insufficient in-canal storage to operate on-demand. Thus, most flow changes must be routed through the canal. Volume compensation has been proposed as a method for easily applying feedforward control to irrigation canals. SacMan (Software for Automated Ca...

Endodontic management of contralateral mandibular first molars with six root canals

PubMed Central

Bhargav, Kambhampati; Sirisha, Kantheti; Jyothi, Mandava; Boddeda, Mohan Rao

2017-01-01

The knowledge of variations in root canal morphology is essential for a successful endodontic outcome. Contralateral mandibular molar with six root canals is a rare entity. Root canal treatment of mandibular molars with aberrant canal configuration can be diagnostically and technically challenging. While dealing with variant mandibular molars, mishaps may happen. This case report describes variations in contralateral mandibular molars and also an endodontic mishap while managing them. PMID:29259369

Endodontic management of a mandibular first molar with six root canal systems.

PubMed

Jain, Dilip; Reddy, Smitha; Venigalla, Bhuvan Shome; Kamishetty, Shekhar

2015-01-01

Internal anatomy of pulp is complex. The first mandibular molars typically have two roots, one mesial with two root canals and another distal root, which contains one or two canals. A 20-year-old female patient reported with intermittent pain and incomplete root canal treatment in left lower back region since 1-week. Refined access cavity revealed initially two canals in mesial and two canals in the distal root. With operating microscope and cone beam computerized tomography, two additional canals (L-mesio-buccal and B-mesio-lingual) were identified in mesial root. One-year follow-up showed patient was asymptomatic and complete healing of periapical radiolucency.

Semicircular Canal Pressure Changes During High-intensity Acoustic Stimulation.

PubMed

Maxwell, Anne K; Banakis Hartl, Renee M; Greene, Nathaniel T; Benichoux, Victor; Mattingly, Jameson K; Cass, Stephen P; Tollin, Daniel J

2017-08-01

Acoustic stimulation generates measurable sound pressure levels in the semicircular canals. High-intensity acoustic stimuli can cause hearing loss and balance disruptions. To examine the propagation of acoustic stimuli to the vestibular end-organs, we simultaneously measured fluid pressure in the cochlea and semicircular canals during both air- and bone-conducted sound presentation. Five full-cephalic human cadaveric heads were prepared bilaterally with a mastoidectomy and extended facial recess. Vestibular pressures were measured within the superior, lateral, and posterior semicircular canals, and referenced to intracochlear pressure within the scala vestibuli with fiber-optic pressure probes. Pressures were measured concurrently with laser Doppler vibrometry measurements of stapes velocity during stimulation with both air- and bone-conduction. Stimuli were pure tones between 100 Hz and 14 kHz presented with custom closed-field loudspeakers for air-conducted sounds and via commercially available bone-anchored device for bone-conducted sounds. Pressures recorded in the superior, lateral, and posterior semicircular canals in response to sound stimulation were equal to or greater in magnitude than those recorded in the scala vestibuli (up to 20 dB higher). The pressure magnitudes varied across canals in a frequency-dependent manner. High sound pressure levels were recorded in the semicircular canals with sound stimulation, suggesting that similar acoustical energy is transmitted to the semicircular canals and the cochlea. Since these intralabyrinthine pressures exceed intracochlear pressure levels, our results suggest that the vestibular end-organs may also be at risk for injury during exposure to high-intensity acoustic stimuli known to cause trauma in the auditory system.

24. VIEW SHOWING WASTE GATES ON GRAND CANAL AT JUNCTION ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

24. VIEW SHOWING WASTE GATES ON GRAND CANAL AT JUNCTION WITH OLD CROSSCUT NE/4, Sec. 7, TIN, R4E; LOOKING WEST. OLD CROSSCUT CANAL ENTERS FROM RIGHT. WASTE GATE ON LEFT EMPTIES INTO SALT RIVER BED Photographer: Kevin Kreisel-Coons, May 1990 - Grand Canal, North side of Salt River, Tempe, Maricopa County, AZ

178. Photocopy of Photograph, Twin Falls Canal Company. C. R. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

178. Photocopy of Photograph, Twin Falls Canal Company. C. R. Savage, Photographer, March, 1905. FIRST FULL WATER OVER MILNER DAM, TWIN FALLS COUNTY, MILNER, IDAHO; SOUTHWEST VIEW OF SPILLWAY GATES. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

66. 'CANAL BOAT ENROUTE NEAR HACKETTSTOWN' READS THE PHOTOGRAPHS CAPTION. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

66. 'CANAL BOAT ENROUTE NEAR HACKETTSTOWN' READS THE PHOTOGRAPHS CAPTION. BOAT IS QUITE POSSIBLY APPROACHING LOCK 2 EAST FROM THE EAST DUE TO SIMILARITIES BETWEEN THIS AND THE PREVIOUS PHOTOGRAPH (I.E. TREES BORDERING THE LOCK AND THE CANAL TENDER'S HOUSE THAT IS VISIBLE TO RIGHT IN THIS PHOTOGRAPH). - Morris Canal, Phillipsburg, Warren County, NJ

Looking east at canal and R. Paul Smith Power Station. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Looking east at canal and R. Paul Smith Power Station. The dark trestle at right center carried the spur track to coal unloading facilities located in the space now occupied by the coal pile. - Potomac Edison Company, Chesapeake & Ohio Canal Bridge, Spanning C & O Canal South of U.S. 11, Williamsport, Washington County, MD

A review of potential tsunami impacts to the Suez Canal

NASA Astrophysics Data System (ADS)

Finkl, C.; Pelinovsky, E.

2012-04-01

Destructive tsunamis in the eastern Mediterranean and Red seas, induced by earthquakes and/or volcanic activity, pose potential hazards to docked seaport shipping and fixed harbor infrastructure as well as to in-transit international shipping within the Suez Canal. Potential vulnerabilities of the Suez Canal to possible tsunami impacts are reviewed by reference to geological, historical, archaeoseismological, and anecdotal data. Tsunami catalogues and databases compiled by earlier researchers are perused to estimate potential return periods for tsunami events that could affect directly the Suez Canal and its closely associated operational infrastructures. Analysis of these various records indicates a centurial return period, or multiples thereof, for long-wave repetition that could generally affect the Nile Delta. It is estimated that tsunami waves 2 m high would have a breaking length about 5 km down Canal whereas a 10 m wave break would occur about 1 km into the Canal. Should a tsunami strike the eastern flanks of the Nile Delta, it would damage Egypt's maritime infrastructure and multi-national commercial vessels and military ships then using the Canal.

Root canal morphology of South Asian Indian maxillary molar teeth

PubMed Central

Singh, Shishir; Pawar, Mansing

2015-01-01

Objective: The objective was to study the root canal morphology of South Asian Indian Maxillary molars using a tooth clearing technique. Materials and Methods: Hundred teeth each comprising of first, second, and third molars collected from different dental schools and clinics in India were subjected to standard dye penetration, decalcification and clearing procedure before being studied. Results: The first molar mesiobuccal roots exhibited 69% Type I, 24% Type II, 4% Type IV, 2% Type V, and 1% exhibited a Vertuccis Type VIII canal anatomy. In the group with three separate roots the second molar mesiobuccal roots in exhibited 80.6% Type I, 15.3% Type II, 2.7% Type IV, and 1.4% Type V canal anatomy while the third molars mesiobuccal roots exhibited 57.4% Type I, 32% Type II, 2.1% Type III, 8.5% Type IV, 1% had a Type V canal anatomy in the similar group. Conclusion: A varied root canal anatomy was seen in the mesiobuccal root canal of the maxillary molars. PMID:25713497

Shaping ability of nickel-titanium rotary instruments in curved root canals.

PubMed

Talati, Ali; Moradi, Saeed; Forghani, Maryam; Monajemzadeh, Ali

2013-01-01

Disinfection and subsequent obturation of the root canal space require adequate mechanical enlargement of the canals. The purpose of this in vitro study was to compare the shaping ability of Mtwo, RaCe and Medin rotary instruments during the preparation of curved root canals. Sixty mesiobuccal root canals of mandibular molars with severe curvatures between 25-35(°) and radius of 4-9 mm were randomly divided into three groups of 20 canals each. Using pre- and post-instrumentation radiographs, straightening of the canal and the apical transportation were determined with AutoCAD software. The data were analyzed using Chi square, analysis of variance, and post-hoc tests and the significance level was set at P<0.05. Mtwo instruments maintained the canal curvature significantly better than Race and Medin instruments (P<0.05). There was significant difference between the rotary instruments for iatrogenic transportation of the major foramen (P>0.05). Under the conditions of this in vitro study, Mtwo instruments seemed superior to the two other rotary instruments.

Endodontic treatment of a mandibular second premolar with three root canals.

PubMed

Aguiar, Carlos; Mendes, Daniela; Câmara, Andréa; Figueiredo, Jose

2010-03-01

The purpose of this case report is to describe a nonsurgical endodontic treatment of a mandibular left second premolar with two separate roots and three distinct root canals. In endodontics, the possible existence of extra canals must be considered before endodontic treatment is instituted. A wide morphological variation of the root canal system is known to exist. A 36-year-old male patient was referred for endodontic treatment on the left mandibular second premolar. Radiographic examination of the involved tooth revealed an unusual, complex root canal anatomy. There was an irregular root morphology consisting of two distinct roots and three canals. This case report describes the successful nonsurgical endodontic treatment of a mandibular left second premolar with two separate roots and three distinct root canals filled using size 35 Thermafil gutta-percha carriers and AH Plus sealer. On the one-year follow-up radiograph, the tooth was asymptomatic, confirming adequate healing with no complications. Even in a tooth with an extremely complex root canal morphology, conventional endodontic treatment without surgical intervention can result in adequate healing without any complications.

Study of Mastoid Canals and Grooves in North Karnataka Human Skulls

PubMed Central

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. Material and Methods: 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. Results: 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. Conclusion: 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. PMID:24086832

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

PubMed

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.

157. Photocopy of drawing (taken from Twin Falls Canal Company ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

157. Photocopy of drawing (taken from Twin Falls Canal Company Field Book #360, Page 75, entitled, 'Clay-Seam Cut-Off.' Cross-Reference: ID-15-153). MILNER DAM SURVEY, TWIN FALLS COUNTY, MILNER, IDAHO. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

151. Photocopy of drawing (taken from Twin Falls Canal Company ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

151. Photocopy of drawing (taken from Twin Falls Canal Company Surveyor's Transit Book #363, Page 20). SURVEY PRINT SHOWING POINT SPILLWAY AND FIELD NOTES, TWIN FALLS COUNTY NORTHWEST OF MURTAUGH, IDAHO. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

153. Photocopy of drawing (taken from Twin Falls Canal Company ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

153. Photocopy of drawing (taken from Twin Falls Canal Company Field Book #360, Page 74, entitled, 'Clay-Seam Cut-Off.' Cross-Reference: ID-15-157). MILNER DAM SURVEY, TWIN FALLS COUNTY, MILNER, IDAHO. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

155. Photocopy of transit book (taken from Twin Falls Canal ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

155. Photocopy of transit book (taken from Twin Falls Canal Company Surveyor's Transit Book #405T, Page 1, #46 Division One). STATEMENT RE: SURVEY ALIGNMENT 3/03, TWIN FALLS COUNTY, MILNER, IDAHO. - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

192. Photocopy of drawing, Twin Falls Canal Company, date unknown. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

192. Photocopy of drawing, Twin Falls Canal Company, date unknown. TOPOGRAPHICAL MAP (DAM DRAWN IN), MILNER SITE, TWIN FALLS COUNTY, MILNER, IDAHO; RIGHT SIDE OF MAP (LEFT ON ID-15-183). - Milner Dam & Main Canal: Twin Falls Canal Company, On Snake River, 11 miles West of city of Burley, Idaho, Twin Falls, Twin Falls County, ID

Viperous fangs: development and evolution of the venom canal.

PubMed

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

Mechanics of the Panama Canal slides

USGS Publications Warehouse

Becker, George F.

1917-01-01

Dr. Becker visited the Canal Zone in 1913 as a geologist of the United States Geological Survey and since that time has given the problem the benefit of his study. His appointment as a member of the committee of the National Academy of Sciences has made it appropriate for his conclusions, based upon his personal observations and already reported in part to the Canal Commission, to be stated for the benefit of his associates and other American scientists and engineers.

Discharge rate measurements in a canal using radiotracer methods.

PubMed

Pant, H J; Goswami, Sunil; Biswal, Jayashree; Samantray, J S; Sharma, V K

2016-06-01

Discharge rates of water were measured in a canal using radiotracer methods with an objective to validate the efficacy of Concrete Volute Pumps (CVPs) installed at various pumping stations along the canal. Pulse velocity and dilution methods were applied to measure the discharge rates using Iodine-131 as a radiotracer. The discharge rate measured in one of the sections of the canal using the pulse velocity method was found to be 22.5m(3)/s, whereas the discharge rates measured using the dilution method in four different sections of the canal varied from 20.27 to 20.62m(3)/s with single CVP in operation. The standard error in discharge rate measurements using dilution method ranged from ±1.1 to ±1.8%. The experimentally measured values of the discharge rate were in good agreement with the design value of the discharge rate (20m(3)/s) thus validating the performance of the CVPs used in the canal. Copyright © 2016 Elsevier Ltd. All rights reserved.

75 FR 56094 - Delta-Mendota Canal Intertie Project

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-15

... and maintenance road along the canal would be used to set the transmission structures. Although span... access and maintenance road would be realigned where necessary to accommodate transmission line... DMC. The route also allowed use of the existing canal access and maintenance road to be used for...

Endodontic management of radix paramolaris with six canals: a clinical case report.

PubMed

Acharya, N; Singh, A; Samant, P S; Gautam, V

2013-01-01

Endodontic therapy of mandibular molars is a challenging task due to its varied root canal morphology. A mandibular first molar with additional buccal root (Radix paramolaris) and additional distolingual root (Radix Entomolaris) is an example of its varied anatomy. A successful management of atypical root canal configurations is an important aspect in determining the success rate of root canal therapy. The detail knowledge of the root morphology and canal anatomy allows the clinician for accurate location of the extra roots and canals and accordingly the refinement of the access cavity for the stress free entry of complex anatomy. Hence, for a successful root canal therapy, clinician must be aware of the external and internal anatomic variations .The aim of this clinical case report is to present and describe the unusual presence of two separate mesial roots and six root canals in mandibular first molar, detected during routine endodontic therapy.

Surgical treatment of atrioventricular canal defect.

PubMed

Hardesty, R L; Zuberbuhler, J R; Bahnson, H T

1975-11-01

Fifty-nine patients with congenital anomalies of the atrioventricular canal underwent operation and all survivors were followed up. In 42 patients with partial atrioventricular canal defects, ten had preoperative congestive heart failure. Three, or 7.1%, died of endomyocardial fibroelastosis, high pulmonary vascular resistance, and severe mitral regurgitation. A fourth patient later died of Wolff-Parkinson-White syndrome and fibrilation. Reoperations in five patients were all successful. No patients had persistent atrioventricular blocks, and all patients are asymptomatic. Two of these subjects continue to receive digoxin therapy, and one of them is believed to have substantial mitral insufficiency. Of the 17 patients who had complete atrioventricular canal defects, 13 had a divided common anterior leaflet attached to the septum by chordae tendineae, and four had undivided and unattached anterior leaflets. Two had previously undergone pulmonary banding, and nine were treated for congestive heart failure. Six died after operation. There were no reoperations. No patient presently has required a pacemaker. Two subjects have persistent cardiomegaly.

Nodular Fasciitis of External Auditory Canal

PubMed Central

Ahn, Jihyun; Kim, Sunyoung; Park, Youngsil

2016-01-01

Nodular fasciitis is a pseudosarcomatous reactive process composed of fibroblasts and myofibroblasts, and it is most common in the upper extremities. Nodular fasciitis of the external auditory canal is rare. To the best of our knowledge, less than 20 cases have been reported to date. We present a case of nodular fasciitis arising in the cartilaginous part of the external auditory canal. A 19-year-old man complained of an auricular mass with pruritus. Computed tomography showed a 1.7 cm sized soft tissue mass in the right external auditory canal, and total excision was performed. Histologic examination revealed spindle or stellate cells proliferation in a fascicular and storiform pattern. Lymphoid cells and erythrocytes were intermixed with tumor cells. The stroma was myxoid to hyalinized with a few microcysts. The tumor cells were immunoreactive for smooth muscle actin, but not for desmin, caldesmon, CD34, S-100, anaplastic lymphoma kinase, and cytokeratin. The patient has been doing well during the 1 year follow-up period. PMID:27304679

48. SUMMIT OF THE MORRIS CANAL, 914 FEET ABOVE MEAN ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

48. SUMMIT OF THE MORRIS CANAL, 914 FEET ABOVE MEAN HIGH TIDE AT NEWARK, NEW JERSEY. TRACKS OF THE D, L & W RAILROAD CAN BE SEEN AT LEFT. EDGE OF THE LAKE HOPATCONG STATION IS ALSO VISIBLE AT LEFT. PASSENGERS AND FREIGHT COULD BE TRANSFERRED TO SMALL BOATS FOR TRANSPORT THROUGH THE FEEDER CANAL TO LAKE HOPATCONG. - Morris Canal, Phillipsburg, Warren County, NJ

DOWNSTREAM-WATER-LEVEL CONTROL TEST RESULTS ON THE WM LATERAL CANAL

USDA-ARS?s Scientific Manuscript database

On steep canals, distant downstream water-level control can be challenging. SacMan (Software for Automated Canal Management) was developed, in part, to test various distant downstream water level controllers. It was implemented on the WM canal of the Maricopa Stanfield Irrigation and Drainage Distri...

Root canal morphology of primary molars: a micro-computed tomography study.

PubMed

Fumes, A C; Sousa-Neto, M D; Leoni, G B; Versiani, M A; da Silva, L A B; da Silva, R A B; Consolaro, A

2014-10-01

This was to investigate the root canal morphology of primary molar teeth using micro-computed tomography. Primary maxillary (n = 20) and mandibular (n = 20) molars were scanned at a resolution of 16.7 μm and analysed regarding the number, location, volume, area, structured model index (SMI), area, roundness, diameters, and length of canals, as well as the thickness of dentine in the apical third. Data were statistically compared by using paired-sample t test, independent sample t test, and one-way analysis of variance with significance level set as 5%. Overall, no statistical differences were found between the canals with respect to length, SMI, dentine thickness, area, roundness, and diameter (p > 0.05). A double canal system was observed in the mesial and mesio-buccal roots of the mandibular and maxillary molars, respectively. The thickness in the internal aspect of the roots was lower than in the external aspect. Cross-sectional evaluation of the roots in the apical third showed flat-shaped canals in the mandibular molars and ribbon- and oval-shaped canals in the maxillary molars. External and internal anatomy of the primary first molars closely resemble the primary second molars. The reported data may help clinicians to obtain a thorough understanding of the morphological variations of root canals in primary molars to overcome problems related to shaping and cleaning procedures, allowing appropriate management strategies for root canal treatment.

Conventional root canal therapy of C-shaped mandibular second molar. A case report.

PubMed

Lynn, Evan A

2006-11-01

The C-shaped root canal system and treatment implications were first described by Cooke and Cox in 1979. C-shaped canals are most frequently found in mandibular second molars, but they can occur in any mandibular molar, and they have been reported in maxillary molars as well. C-shaped mandibular molars are characterized by a C-shaped groove that connects one or more root canals. This groove can occur anywhere along the root canal system, making it difficult to diagnose and treat. A C-shaped root canal system may appear completely normal at the level of the pulp chamber but can begin to manifest itself in the middle or apical one-third. Furthermore, C-shaped canals are challenging if not impossible to predict radiographically. C-shaped canals in mandibular second molars are found most frequently in the Chinese population, with reports showing up to a 31.5% incidence, as compared to an approximate 7% incidence in the general population. This case report demonstrates an incidence of a C-shaped canal that was unable to be detected radiographically and which contained three separate root canals that communicated in the apical one-third of the root canal system. Canal orifices were located approximately 2 mm below the level of the CEJ, which is in agreement with a recent micro-computed tomography study of C-shaped mandibular molars that found 98% of all C-shaped molars studied had orifices located 1 mm to 3 mm below the CEJ. The CT study also found that all C-shaped canals contained fused roots and confirmed previous findings that the C-shape configuration varies greatly throughout the length of the canal.

33 CFR 117.653 - St. Mary's Falls Canal.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false St. Mary's Falls Canal. 117.653 Section 117.653 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Michigan § 117.653 St. Mary's Falls Canal. The draw of...

33 CFR 117.653 - St. Mary's Falls Canal.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false St. Mary's Falls Canal. 117.653 Section 117.653 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Michigan § 117.653 St. Mary's Falls Canal. The draw of...

33 CFR 117.653 - St. Mary's Falls Canal.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false St. Mary's Falls Canal. 117.653 Section 117.653 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Michigan § 117.653 St. Mary's Falls Canal. The draw of...

33 CFR 117.653 - St. Mary's Falls Canal.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false St. Mary's Falls Canal. 117.653 Section 117.653 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Michigan § 117.653 St. Mary's Falls Canal. The draw of...

33 CFR 117.653 - St. Mary's Falls Canal.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false St. Mary's Falls Canal. 117.653 Section 117.653 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Michigan § 117.653 St. Mary's Falls Canal. The draw of...

Investigations into in situ Enterococcus faecalis biofilm removal by passive and active sodium hypochlorite irrigation delivered into the lateral canal of a simulated root canal model.

PubMed

Mohmmed, S A; Vianna, M E; Penny, M R; Hilton, S T; Mordan, N J; Knowles, J C

2018-06-01

To investigate in situ Enterococcus faecalis biofilm removal from the lateral canal of a simulated root canal system using passive or active irrigation protocols. Root canal models (n = 43) were manufactured from transparent resin materials using 3D printing. Each canal was created with an 18 mm length, apical size 30, a .06 taper and a lateral canal of 3 mm length, with 0.3 mm diameter. Biofilms were grown in the lateral canal and apical 3 mm of the main canal for 10 days. Three models from each group were examined for residual biofilm using SEM. The other forty models were divided into four groups (n = 10). The models were observed under a fluorescence microscope. Following 60 s of 9 mL of 2.5% NaOCl irrigation using syringe and needle, the irrigant was either left stagnant in the canal or activated using gutta-percha, sonic or ultrasonic methods for 30 s. Images were then captured every second using an external camera. The residual biofilm percentages were measured using image analysis software. The data were analysed using generalized linear mixed models. A significance level of 0.05 was used throughout. The greatest level of biofilm removal was obtained with ultrasonic agitation (66.76%) followed by sonic (45.49%), manual agitation (43.97%) and passive irrigation groups (38.67%), respectively. The differences were significant between the residual biofilm in the passive irrigation and both sonic and ultrasonic groups (P = 0.001). Agitation resulted in better penetration of 2.5% NaOCl into the lateral canal of an artificial root canal model. Ultrasonic agitation of NaOCl improved the removal of biofilm. © 2017 International Endodontic Journal. Published by John Wiley & Sons Ltd.

12. MAIN CANAL SPILLWAY AND WASTEWAY NO. 2, JUST ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

12. MAIN CANAL - SPILLWAY AND WASTEWAY NO. 2, JUST ABOVE DARK CANYON SIPHON. VIEW TO SOUTH - Carlsbad Irrigation District, Main Canal, 4 miles North to 12 miles Southeast of Carlsbad, Carlsbad, Eddy County, NM

Endodontic management of maxillary first molar with atypical canal morphology: Report of three cases

PubMed Central

Sherwani, Osama Adeel Khan; Kapoor, Bhumika; Sharma, Rajat; Mishra, Surendra Kumar

2016-01-01

Maxillary first molar with three roots and 3–4 canals is a common occurrence. However, extreme variations in their canal morphology have been reported ranging from one single canal and one root to as many as eight root canals. This article presents three cases of successful endodontic management of maxillary first molars with atypical canal morphologies, thus highlighting the fact that variations do occur and an endodontist should always be aware of aberrancies in root canal system apart from the knowledge of normal root canal anatomy. PMID:27994427

Patterns of directional asymmetry in the pelvis and pelvic canal.

PubMed

Tobolsky, Victoria A; Kurki, Helen K; Stock, Jay T

2016-11-01

The human pelvis is unique among modern taxa for supporting both parturition of large brained young and obligate bipedalism. Though much work has focused on pelvic development and variation, little work has explored the presence or absence of asymmetry in the pelvis despite well-known patterns of asymmetry in other skeletal regions. This study investigated whether patterns of directional asymmetry (DA) could be observed in the pelvis or pelvic canal. Seventeen bilaterally paired osteometric measurements of the os coxae (34 measures in total) were taken from 128 skeletons (female n = 65, male n = 63) from recent human populations in five geographic regions. Paired sample t-tests and Mann-Whitney U-tests were used to investigate DA. Results from a pooled sample of all individuals showed that the pelvis exhibited a left-bias in DA. In contrast, the pelvic canal exhibited a pattern in which the anterior canal exhibited a right-bias and the posterior canal exhibited a left-bias. Neither sex nor populational differences in DA were observed in the pelvis or pelvic canal. The varying patterns of asymmetry uncovered here accord with prior work and may indicate that loading from the trunk and legs place differing stresses on the pelvis and canal, yielding these unequal asymmetries. However, this is speculative and the possible influence of genetics, biomechanics, and nutritional status on the development of pelvic and canal asymmetries presents a rich area for future study. Additionally, the potential influence of pelvic canal asymmetry on obstetric measures of pelvic capacity merits future research. Am. J. Hum. Biol. 28:804-810, 2016. © 2016Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Temporal and Spatial Variation of Chemical Water Quality in a Contour Canal.

NASA Astrophysics Data System (ADS)

Swanson, L. A.; Lunn, R. J.

2004-12-01

Chemical water quality is a highly variable aspect of any water body. Historically numerous researchers have investigated the chemical variability of rivers, streams and wetlands, artificial water bodies such as canals have been largely neglected. Canals are typically hydraulically characterised by low flows and a lack of mixing processes. This can potentially lead to significant spatial variability in water chemistry, and as a result many canals in the UK regularly fail water quality targets at specific locations. Recent changes to UK legislation, following the European Water Framework Directive (2000/60/EC), have resulted in canals being subject to achieving `good ecological status'. In the case of canals, what constitutes `good ecological status' is largely unknown and little expertise is available since historically canal management has not been driven by chemical and ecological quality targets. Consequently, there is an urgent need for new research to determine the main factors influencing canal water quality and their ecological status. This research presents results from a study based on a UK contour canal, the Union Canal in central Scotland. The Union Canal typically demonstrates spatially and temporally variable levels of dissolved oxygen (DO) and orthophosphate (PO4-P): simultaneously, seasonal and diel fluctuations of DO and PO4-P are pronounced at a small number of locations. During 1995, minimum levels of DO along the canal length ranged from 9mgl-1 in Edinburgh to as low as 2mgl-1 approximately 20kms away, this then rose again to 8mgl-1 after a further distance of 2km. These acutely low levels of DO are coupled with events of excessive PO4-P up to 0.235mgl-1:10 times greater than those normally found in rivers, causing localised eutrophication and extensive fish kills. To determine the cause of the `hot spots' of poor water quality found on the Union Canal, simultaneous investigations of the hydraulic regime, spatial and temporal water quality

Canalolithiasis of the superior semicircular canal: an anomaly in benign paroxysmal vertigo.

PubMed

Schratzenstaller, Bruno; Wagner-Manslau, Carola; Strasser, Gerhard; Arnold, Wolfgang

2005-10-01

According to the canalolithiasis theory, benign paroxysmal vertigo (BPPV) is caused by gravity-dependent movements of otoconial debris that collects in the endolymph of the posterior semicircular canal. Other parts of the vestibular organ are rarely affected, and it is mainly the horizontal canal that is affected by this atypical form of BPPV. Canalolithiasis of the superior semicircular canal must be considered an anomaly because the superior semicircular canal is the highest point of the vestibular organ and debris normally cannot collect in this special location. Until now, BPPV of the superior canal has mainly been dealt with theoretically in the literature. The authors present three patients with canalolithiasis of the superior semicircular canal and offer direct proof of the condition using high-resolution 3D MRI.

1. BLACK RIVER CANAL PARSHALL FLUME AT UPPER END ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. BLACK RIVER CANAL - PARSHALL FLUME AT UPPER END OF SUPPLY (USED BY STATE ENGINEER). VIEW TO NORTHEAST - Carlsbad Irrigation District, Black River Canal, 15 miles Southeast of Carlsbad near Malaga, Carlsbad, Eddy County, NM

20. 1934 aerial of Tempe Canal, Sections 9, 16, and ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

20. 1934 aerial of Tempe Canal, Sections 9, 16, and 17 (T1N R5E) (top of page is north). The Tempe Crosscut is seen as the dark line entering from top right, which turns north, then curves around the Chandler Falls powerhouse. The canal then curves slowly around to the southwest. The old Trunk Ditch is visible at the top of the curve, coming in from the northeast. A wasteway (top left) runs west from the canal to the Salt River. Photographer: Unknown, 1934. Source: SRP Cartographic Drafting - Tempe Canal, South Side Salt River in Tempe, Mesa & Phoenix, Tempe, Maricopa County, AZ

21. 1934 aerial of Tempe Canal, Sections 19 and 30 ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

21. 1934 aerial of Tempe Canal, Sections 19 and 30 (T1N R5E) and Sections 24 and 25 (T1N R4E) (top of page is north). The main canal enters the picture at upper right and curves out of picture at lower right. The Hayden Branch (thin dark line) runs from top of picture to the southwest, then curves to the west. The Western Branch enters picture running parallel to main canal, then angles off to southwest. Photographer: Unknown, 1934. Source: SRP Cartographic Drafting - Tempe Canal, South Side Salt River in Tempe, Mesa & Phoenix, Tempe, Maricopa County, AZ

Association of Unfinished Root Canal Treatments with the Risk of Pneumonia Hospitalization.

PubMed

Lin, Po-Yen; Chiang, Yu-Chih; Chou, Yu-Ju; Chang, Hong-Ji; Chi, Lin-Yang

2017-01-01

The objective of root canal treatments (RCTs) is to control pulpal diseases and salvage infected teeth by eradicating microorganisms within the root canal system. However, an unfinished RCT can leave a space for bacterial accumulation, which can leak into the oral cavity and then aspirate into the lower respiratory tract and the lungs, causing infection. This study investigated the association of unfinished RCTs with the possible risk of pneumonia hospitalization using a nationwide population-based database. After a matching process, we recruited 116,490 subjects who received an initiated RCT and had no history of pneumonia before 2005 and observed until the end of 2011. An unfinished RCT was operationally defined as an endodontic session that was started on a tooth but had no subsequent completion records. Cox proportional hazards models and subgroup analyses were used to estimate the association of unfinished RCTs on the risk of pneumonia hospitalization. In total, 1285 subjects were hospitalized for pneumonia during 2005 to 2011 with an overall pneumonia hospitalization incidence rate of 0.22% per person year. After adjusting for confounding factors, the adjusted pneumonia hospitalization hazard ratio for subjects who had unfinished RCTs was 1.40 (95% confidence interval, 1.24-1.59) compared with subjects without unfinished RCTs (P < .0001). For middle-aged patients, the hazard ratio was 1.81 (95% confidence interval, 1.45-2.24). Patients with unfinished RCTs had a higher risk of pneumonia hospitalization. Thus, dentists are advised to complete endodontic treatments once started. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Distortion product otoacoustic emissions upon ear canal pressurization.

PubMed

Zebian, Makram; Schirkonyer, Volker; Hensel, Johannes; Vollbort, Sven; Fedtke, Thomas; Janssen, Thomas

2013-04-01

The purpose of this study was to quantify the change in distortion product otoacoustic emission (DPOAE) level upon ear canal pressurization. DPOAEs were measured on 12 normal-hearing human subjects for ear canal static pressures between -200 and +200 daPa in (50 ± 5) daPa steps. A clear dependence of DPOAE levels on the pressure was observed, with levels being highest at the maximum compliance of the middle ear, and decreasing on average by 2.3 dB per 50 daPa for lower and higher pressures. Ear canal pressurization can serve as a tool for improving the detectability of DPOAEs in the case of middle-ear dysfunction.

21 CFR 872.3820 - Root canal filling resin.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Root canal filling resin. 872.3820 Section 872.3820 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3820 Root canal filling resin. (a) Identification...

Root and canal morphology of mandibular third molars in an Iranian population.

PubMed

Kuzekanani, Maryam; Haghani, Jahangir; Nosrati, Hossein

2012-01-01

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. 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-nique. Root number and morphology, number of canals per root, root canal configuration according to Vertucci classifica-tion, and incidence of dilacerated roots and C-shaped canals in mandibular third molars were evaluated under stereomicro-scope with ×2 to ×3 magnifications. 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. 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.

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

PubMed

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 < 0.05). The interaction between access design and instrument type showed that the combination of CEC-VB presented significantly higher amounts of remaining obturation materials on the 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 < .05). Neither retreatment protocol was able to completely eliminate all obturation materials from the 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

Two-rooted maxillary first molars with two canals: a case series.

PubMed

Shakouie, Sahar; Mokhtari, Hadi; Ghasemi, Negin; Gholizadeh, Seddigheh

2013-01-01

Thorough understanding of the anatomic and internal morphology of a root canal system is absolutely essential for the success of endodontic treatment. Since permanent maxillary first molars have shown variation in internal anatomy, morphology, this tooth has been reviewed extensively. Presence of two canals in a two-rooted maxillary first molar has rarely been reported in studies describing tooth and root canal anatomies. In this report, three cases are presented, which involve the root canal treatment of maxillary first molars with fusion of the two buccal roots.

Influence of Glide Path Preparation on the Canal Shaping Times of WaveOne Gold in Curved Mandibular Molar Canals.

PubMed

Vorster, Martin; van der Vyver, Peet J; Paleker, Farzana

2018-05-01

The aim of this study was to compare the glide path preparation times of stainless steel hand files, PathFiles (Dentsply Sirona, Ballaigues, Switzerland), and the WaveOne Gold Glider (Dentsply Sirona). The preparation times for final root canal shaping with the Primary WaveOne Gold instrument in extracted human molar teeth with and without prior glide path preparation were also recorded and compared. Mesiobuccal canals of 60 extracted human mandibular molars (curvature angles between 25° and 35° and radii <10 mm) were selected and randomly divided into 4 groups with 15 canals each. Canals were negotiated to patency with a #8 K-file. Canal preparations were performed by a single operator using precurved #10-15-20 stainless steel manual K-files (the K-file group), a #10 stainless steel manual K-file followed by PathFiles #1-3 (the PathFile group), a #10 stainless steel manual K-file followed by WaveOne Gold Glider (the WaveOne Gold Glider group), or no further glide path preparation. Final canal preparation of all 60 canals was performed with the Primary WaveOne Gold instrument. Glide path and final preparation times were recorded. Glide path enlargement was statistically significantly fastest in the WaveOne Gold Glider group (19.7 ± 5.6 seconds) followed by the PathFile group (41.0 ± 6.8 seconds) and then the K-file group (81.2 ± 26.3 seconds) using analysis of variance (ANOVA) and Kruskal-Wallis tests (P < .0001). No statistically significant difference in the mean final preparation times was found among the WaveOne Gold Glider (23.1 ± 6.0 seconds), PathFile (24.4 ± 4.9 seconds), and K-file groups (27.2 ± 9.5 seconds). All 3 groups were statistically significantly faster than the no glide path preparation group (35.4 ± 10.2 seconds) using ANOVA (P = .0004) and Kruskal-Wallis tests (P = .0010). Preparation time with the Primary WaveOne Gold file was statistically significantly reduced when the file was used in combination with any of

Composite resin reinforcement of flared canals using light-transmitting plastic posts.

PubMed

Lui, J L

1994-05-01

Composite resins have been advocated as a reinforcing build-up material for badly damaged endodontically treated teeth with flared canals. However, the control of an autocuring composite resin is difficult because it polymerizes rapidly within the root canal. While the light-curing composite resins are more user friendly, their polymerization can be a problem deep in the root canal. Light-transmitting plastic posts allow the transmission of light into the root canal and enable intraradicular composite resin reconstitution and reinforcement of weakened roots. At the same time, the light-transmitting plastic post forms an optimal post canal in the rehabilitated root and can accurately fit a matching retentive final post. These light-transmitting posts are a useful addition to the dental armamentarium.

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

NASA Astrophysics Data System (ADS)

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

A comparison between effect of photodynamic therapy by LED and calcium hydroxide therapy for root canal disinfection against Enterococcus faecalis: A randomized controlled trial.

PubMed

Asnaashari, Mohammad; Ashraf, Hengameh; Rahmati, Afsaneh; Amini, Neda

2017-03-01

Insufficient root canal disinfection is one of the main reasons for persistent periapical pathology. Photodynamic therapy (PDT) has been proven effective in disinfecting infected root canals. The aim of this study was to evaluate the antimicrobial effect of photo activated disinfection (PAD) when using toluidine blue as photosensitizer and a LED lamp after the conventional treatment, and comparing it with calcium hydroxide therapy in vivo. This clinical trial includes 20 patients with molars requiring endodontic retreatment. After the conventional treatment, first microbiological samples were obtained using sterile rotary ProTaper F2 file and 3 paper points and transferred to a microbiology laboratory. Group 1 (n=10) specimens underwent PAD with photosensitizer (PS) solution (0.1mg/mL TB) and irradiation with Fotosan light emitting diode (LED) lamp (635nm, 200mW/cm2) for 60s. Creamy Ca(OH)2 paste was used in group 2 (n=10) for two weeks. A second sample was then obtained. The samples were cultured and then bacterial colonies were counted. Data included number of colony forming units (CFUs) before and after treatments, analyzed by t-test and analysis of covariance (ANCOVA) using SPSS vs.18. A significant difference between results of before and after treatment of both groups (calcium hydroxide therapy p=0.02<0.05, PAD p<0.0001) indicated the efficacy of both treatments. The mean numbers for log 10CFUs/mL before calcium hydroxide therapy and PAD with LED irradiation was 10.1968 and 11.3773. After treatment, the mean numbers were 9.4202 and 8.3772, respectively. The difference in results after treatment between groups was significant (p=0.01<0.05) and indicate that PAD was more effective. PAD and calcium hydroxide therapy, as auxiliary methods adjunct to conventional root canal therapy, are both effective in root canal disinfection. In comparison with calcium hydroxide therapy, PAD leads to a greater reduction in enterococcus faecalis number in the infected root