WorldWideScience

Sample records for canal operations

  1. Research on Canal System Operation Based on Controlled Volume Method

    Directory of Open Access Journals (Sweden)

    Zhiliang Ding

    2009-10-01

    Full Text Available An operating simulation mode based on storage volume control method for multireach canal system in series was established. In allusion to the deficiency of existing controlled volume algorithm, the improved algorithm was proposed, that is the controlled volume algorithm of whole canal pools, the simulation results indicate that the storage volume and water level of each canal pool can be accurately controlled after the improved algorithm was adopted. However, for some typical discharge demand change operating conditions of canal, if the controlled volume algorithm of whole canal pool is still adopted, then it certainly will cause some unnecessary regulation, and consequently increases the disturbed canal reaches. Therefor, the idea of controlled volume operation method of continuous canal pools was proposed, and its algorithm was designed. Through simulation to practical project, the results indicate that the new controlled volume algorithm proposed for typical operating condition can comparatively obviously reduce the number of regulated check gates and disturbed canal pools for some typical discharge demand change operating conditions of canal, thus the control efficiency of canal system was improved. The controlled volume method of operation is specially suitable for large-scale water delivery canal system which possesses complex operation requirements.

  2. 76 FR 69131 - Drawbridge Operation Regulation; Lake Washington Ship Canal, Seattle, WA

    Science.gov (United States)

    2011-11-08

    ... SECURITY Coast Guard 33 CFR Part 117 Drawbridge Operation Regulation; Lake Washington Ship Canal, Seattle... the operation of the Burlington Northern Santa Fe Railway Bridge across the Lake Washington Ship Canal... Lake Washington Ship Canal, mile 0.1, for vessel traffic for a 14 day period to facilitate...

  3. 77 FR 25590 - Drawbridge Operation Regulation; Lake Washington Ship Canal, Seattle, WA

    Science.gov (United States)

    2012-05-01

    ... SECURITY Coast Guard 33 CFR Part 117 Drawbridge Operation Regulation; Lake Washington Ship Canal, Seattle... across the Lake Washington Ship Canal, mile 4.3, at Seattle, WA. This deviation is necessary to... crosses the Lake Washington Ship Canal at mile 4.3 and while in the closed position provides 30 feet...

  4. 78 FR 45056 - Drawbridge Operation Regulation; Lake Washington Ship Canal, Seattle, WA

    Science.gov (United States)

    2013-07-26

    ... SECURITY Coast Guard 33 CFR Part 117 Drawbridge Operation Regulation; Lake Washington Ship Canal, Seattle... Bridge across the Lake Washington Ship Canal, mile 5.2, at Seattle, WA. The deviation is necessary to... pre-game and post game football traffic. The Montlake Bridge crosses the Lake Washington Ship Canal...

  5. 77 FR 25079 - Drawbridge Operation Regulation; Lake Washington Ship Canal, Seattle, WA

    Science.gov (United States)

    2012-04-27

    ... SECURITY Coast Guard 33 CFR Part 117 Drawbridge Operation Regulation; Lake Washington Ship Canal, Seattle... Bridge across the Lake Washington Ship Canal, mile 5.2, at Seattle, WA. This deviation is necessary to... Bridge crosses the Lake Washington Ship Canal at mile 5.2 and while in the closed position provides...

  6. 78 FR 26249 - Drawbridge Operation Regulation; Lake Washington Ship Canal, Seattle, WA

    Science.gov (United States)

    2013-05-06

    ... SECURITY Coast Guard 33 CFR Part 117 Drawbridge Operation Regulation; Lake Washington Ship Canal, Seattle... Bridge across the Lake Washington Ship Canal, mile 5.2, at Seattle, WA, and the University Bridge across the Lake Washington Ship Canal, mile 4.3, at Seattle, WA. This deviation is necessary to...

  7. 77 FR 33307 - Drawbridge Operation Regulation; Lake Washington Ship Canal, Seattle, WA

    Science.gov (United States)

    2012-06-06

    ... SECURITY Coast Guard 33 CFR Part 117 Drawbridge Operation Regulation; Lake Washington Ship Canal, Seattle... Bridge across the Lake Washington Ship Canal, mile 5.2, at Seattle, WA. This deviation is necessary to.... The Montlake Bridge crosses the Lake Washington Ship Canal at mile 5.2 and while in the...

  8. 78 FR 40960 - Drawbridge Operation Regulation; Lake Washington Ship Canal at Seattle, WA

    Science.gov (United States)

    2013-07-09

    ... SECURITY Coast Guard 33 CFR Part 117 Drawbridge Operation Regulation; Lake Washington Ship Canal at Seattle....3, all crossing the Lake Washington Ship Canal at Seattle, WA. The deviation is necessary to... 2.6, and the University Bridge, mile 4.3, all crossing the Lake Washington Ship Canal at Seattle,...

  9. 78 FR 55214 - Drawbridge Operation Regulation; Lake Washington Ship Canal, Seattle, WA

    Science.gov (United States)

    2013-09-10

    ... SECURITY Coast Guard 33 CFR Part 117 Drawbridge Operation Regulation; Lake Washington Ship Canal, Seattle... Northern Santa Fe (BNSF) Railway Bridge across the Lake Washington Ship Canal, mile 0.1, at Seattle, WA.... Chittenden lock immediately upstream or inland of the bridge on the Lake Washington Ship Canal. This...

  10. 78 FR 39591 - Drawbridge Operation Regulation; Lake Washington Ship Canal at Seattle, WA

    Science.gov (United States)

    2013-07-02

    ... SECURITY Coast Guard 33 CFR Part 117 Drawbridge Operation Regulation; Lake Washington Ship Canal at Seattle... the University Bridge, mile 4.3, all crossing the Lake Washington Ship Canal at Seattle, WA. The... elevation of Lake Washington. The current operating schedule for all three bridges is set out in 33 CFR...

  11. Research on Controlled Volume Operation Method of Large-scale Water Transfer Canal

    Institute of Scientific and Technical Information of China (English)

    DING Zhiliang; WANG Changde; XU Duo; XIAO Hua

    2011-01-01

    The controlled volume method of operation is especially suitable for large-scale water delivery canal system with complex operation requirements. An operating simulation model based on the storage volume control method for multi-reach canal system in series was established. In allusion to the deficiency of existing controlled volume algorithm, the improved controlled volume algorithm of the whole canal pools was proposed, and the simulation results indicated that the storage volume and water level of each canal pool could be accurately controlled after the improved algorithm had been adopted. However, for some typical discharge demand operating conditions, if the previously mentioned algorithm was adopted, then it certainly would cause some unnecessary gate adjustments, and consequently the disturbed canal pools would be increased. Therefore, the idea of controlled volume operation method of continuous canal pools was proposed, and corresponding algorithm was designed. Through simulating practical project, the results indicated that the new controlled volume algorithm proposed for typical operating conditions could comparatively and obviously reduce the number of regulated check gates and disturb canal pools for some typical discharge demand operating conditions, thus the control efficiency of canal system could be improved.

  12. Algorithm of Dynamic Operation Process of Hydraulic Automatically Operated Canals with Constant-Downstream Level Gates

    Institute of Scientific and Technical Information of China (English)

    ZHANG Li-wei; FENG Xiao-bo; WANG Chang-de

    2005-01-01

    On the basis of analysis the governing process of downstream water level gates AVIO and AVIS, a mathematical model for simulation of dynamic operation process of hydraulically automated irrigation canals installed with AVIO and AVIS gates is presented. the main point of this mathematical model is firstly applying a set of unsteady flow equations (St. Venant equations here) and treating the condition of gate movement as its dynamic boundary, and then decoupling this interaction of gate movement with the change of canal flow. In this process, it is necessary to give the gates' open-loop transfer function whose input is water level deviation and output is gate discharge. The result of this simulation for a practical reach has shown it has satisfactory accuracy.

  13. 76 FR 14804 - Drawbridge Operation Regulations; Annisquam River and Blynman Canal, Gloucester, MA

    Science.gov (United States)

    2011-03-18

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF HOMELAND SECURITY Coast Guard 33 CFR Part 117 Drawbridge Operation Regulations; Annisquam River and Blynman Canal, Gloucester, MA AGENCY: Coast Guard, DHS. ACTION: Notice of temporary deviation from regulations. SUMMARY:...

  14. 77 FR 6012 - Drawbridge Operation Regulations; Annisquam River and Blynman Canal, Gloucester, MA

    Science.gov (United States)

    2012-02-07

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF HOMELAND SECURITY Coast Guard 33 CFR Part 117 Drawbridge Operation Regulations; Annisquam River and Blynman Canal, Gloucester, MA AGENCY: Coast Guard, DHS. ACTION: Notice of temporary deviation from regulations. SUMMARY:...

  15. 76 FR 79065 - Drawbridge Operation Regulations; Annisquam River and Blynman Canal, Gloucester, MA

    Science.gov (United States)

    2011-12-21

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF HOMELAND SECURITY Coast Guard 33 CFR Part 117 Drawbridge Operation Regulations; Annisquam River and Blynman Canal, Gloucester, MA AGENCY: Coast Guard, DHS. ACTION: Notice of temporary deviation from regulations. SUMMARY:...

  16. 76 FR 45420 - Drawbridge Operation Regulations; Annisquam River and Blynman Canal, Gloucester, MA

    Science.gov (United States)

    2011-07-29

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF HOMELAND SECURITY Coast Guard 33 CFR Part 117 Drawbridge Operation Regulations; Annisquam River and Blynman Canal, Gloucester, MA AGENCY: Coast Guard, DHS. ACTION: Notice of temporary deviation from regulations. SUMMARY:...

  17. 75 FR 78163 - Drawbridge Operation Regulations; Annisquam River and Blynman Canal, Gloucester, MA

    Science.gov (United States)

    2010-12-15

    ..., Gloucester, MA AGENCY: Coast Guard, DHS. ACTION: Notice of temporary deviation from regulations. SUMMARY: The... Blynman Canal at mile 0.7, at Gloucester, MA, has a vertical clearance in the closed position of 16...

  18. 77 FR 44140 - Drawbridge Operation Regulation; Sturgeon Bay Ship Canal, Sturgeon Bay, WI

    Science.gov (United States)

    2012-07-27

    ...; Sturgeon Bay Ship Canal, Sturgeon Bay, WI, in the Federal Register (77 FR 21890). We did not receive any... final rule was published on October 24, 2005 in the Federal Register (70 FR 61380) to allow for one... published on June 5, 2009 in the Federal Register (74 FR 26954), effective from June 1, 2009 to November...

  19. Frequency of second mesiobuccal canal in permanent maxillary first molars using the operating microscope and selective dentin removal: A clinical study

    Directory of Open Access Journals (Sweden)

    Suroopa Das

    2015-01-01

    Full Text Available Purpose: The aim of this study was to investigate whether the combination of operating microscope and selective dentin removal increased the frequency of second mesiobuccal (MB2 canal detection in permanent maxillary first molar teeth. Materials and Methods: One hundred fifty permanent maxillary first molars indicated for root canal treatment were randomly selected from patients belonging to the age group of 18-45 years irrespective of gender. After access cavity preparation and location of main canals, the MB2 canal orifice was sought in all teeth with an endodontic explorer under direct vision (Stage I, then under magnification with the aid of operating microscope (Stage II and finally with the combined use of operating microscope and selective dentin removal (Stage III. Results: MB2 canals were detected in 36%, 54% and 72% of the teeth in Stages I-III, respectively. Conclusion: This study demonstrated that dental operating microscope when used along with adjunctive aids such as selective dentin removal/troughing and good clinical knowledge will increase the ability of dental clinician to locate MB2 canals.

  20. Focused risk assessment: Mound Plant, Miami-Erie Canal Operable Unit 4

    International Nuclear Information System (INIS)

    In 1969, an underground waste line at Mound Plant ruptured and released plutonium-238 in a dilute nitric acid solution to the surrounding soils. Most of the acid was neutralized by the native soils. The plutonium, which in a neutral solution is tightly sorbed onto clay particles, remained within the spill area. During remediation, a severe storm eroded some of the contaminated soil. Fine grained plutonium-contaminated clay particles were carried away through the natural drainage courses to the remnants of the Miami-Erie Canal adjacent to Mound Plant, and then into the Great Miami River. This focused risk assessment considers exposure pathways relevant to site conditions, including incidental ingestion of contaminated soils, ingestion of drinking water and fish, and inhalation of resuspended soils and sediments. For each potential exposure pathway, a simplified conceptual model and exposure scenarios have been used to develop conservative estimates of potential radiation dose equivalents and health risks. The conservatism of the dose and risk estimates provides a substantive margin of safety in assuring that the public health is protected

  1. Focused risk assessment: Mound Plant, Miami-Erie Canal Operable Unit 4

    Energy Technology Data Exchange (ETDEWEB)

    Rogers, D.R.; Dunning, D.F.

    1994-09-29

    In 1969, an underground waste line at Mound Plant ruptured and released plutonium-238 in a dilute nitric acid solution to the surrounding soils. Most of the acid was neutralized by the native soils. The plutonium, which in a neutral solution is tightly sorbed onto clay particles, remained within the spill area. During remediation, a severe storm eroded some of the contaminated soil. Fine grained plutonium-contaminated clay particles were carried away through the natural drainage courses to the remnants of the Miami-Erie Canal adjacent to Mound Plant, and then into the Great Miami River. This focused risk assessment considers exposure pathways relevant to site conditions, including incidental ingestion of contaminated soils, ingestion of drinking water and fish, and inhalation of resuspended soils and sediments. For each potential exposure pathway, a simplified conceptual model and exposure scenarios have been used to develop conservative estimates of potential radiation dose equivalents and health risks. The conservatism of the dose and risk estimates provides a substantive margin of safety in assuring that the public health is protected.

  2. Analysis of C-shaped canal systems in mandibular second molars using surgical operating microscope and cone beam computed tomography: A clinical approach

    Directory of Open Access Journals (Sweden)

    Sanjay Chhabra

    2014-01-01

    Full Text Available Aims: The study was aimed to acquire better understanding of C-shaped canal systems in mandibular second molar teeth through a clinical approach using sophisticated techniques such as surgical operating microscope and cone beam computed tomography (CBCT. Materials and Methods: A total of 42 extracted mandibular second molar teeth with fused roots and longitudinal grooves were collected randomly from native Indian population. Pulp chamber floors of all specimens were examined under surgical operating microscope and classified into four types (Min′s method. Subsequently, samples were subjected to CBCT scan after insertion of K-files size #10 or 15 into each canal orifice and evaluated using the cross-sectional and 3-dimensional images in consultation with dental radiologist so as to obtain more accurate results. Minimum distance between the external root surface on the groove and initial file placed in the canal was also measured at different levels and statistically analyzed. Results: Out of 42 teeth, maximum number of samples (15 belonged to Type-II category. A total of 100 files were inserted in 86 orifices of various types of specimens. Evaluation of the CBCT scan images of the teeth revealed that a total of 21 canals were missing completely or partially at different levels. The mean values for the minimum thickness were highest at coronal followed by middle and apical third levels in all the categories. Lowest values were obtained for teeth with Type-III category at all three levels. Conclusions: The present study revealed anatomical variations of C-shaped canal system in mandibular second molars. The prognosis of such complex canal anatomies can be improved by simultaneous employment of modern techniques such as surgical operating microscope and CBCT.

  3. 76 FR 4574 - Drawbridge Operation Regulations; Oakland Inner Harbor Tidal Canal, Oakland/Alameda, CA, Schedule...

    Science.gov (United States)

    2011-01-26

    ... Federal Register (75 FR 29693-29695). The proposed change would have allowed the drawbridge owner/operator... Charron, Mr. Henry C. Lindemann and The Bay Planning Coalition recommending coordination with...

  4. 77 FR 57019 - Drawbridge Operation Regulation; Lake Washington Ship Canal, Seattle, WA

    Science.gov (United States)

    2012-09-17

    ... deviation is necessary to facilitate heavy maintenance on the bridge including replacing operating strut... Engineering Hiram M. Chittenden lock immediately upstream or inland of the bridge on the Lake Washington...

  5. Successful operative management of an upper lumbar spinal canal stenosis resulting in multilevel lower nerve root radiculopathy

    Directory of Open Access Journals (Sweden)

    Shearwood McClelland

    2015-01-01

    Full Text Available Lumbar stenosis is a common disorder, usually characterized clinically by neurogenic claudication with or without lumbar/sacral radiculopathy corresponding to the level of stenosis. We present a case of lumbar stenosis manifesting as a multilevel radiculopathy inferior to the nerve roots at the level of the stenosis. A 55-year-old gentleman presented with bilateral lower extremity pain with neurogenic claudication in an L5/S1 distribution (posterior thigh, calf, into the foot concomitant with dorsiflexion and plantarflexion weakness. Imaging revealed grade I spondylolisthesis of L3 on L4 with severe spinal canal stenosis at L3-L4, mild left L4-L5 disc herniation, no stenosis at L5-S1, and no instability. EMG revealed active and chronic L5 and S1 radiculopathy. The patient underwent bilateral L3-L4 hemilaminotomy with left L4-L5 microdiscectomy for treatment of his L3-L4 stenosis. Postoperatively, he exhibited significant improvement in dorsiflexion and plantarflexion. The L5-S1 level was not involved in the operative decompression. Patients with radiculopathy and normal imaging at the level corresponding to the radiculopathy should not be ruled out for operative intervention should they have imaging evidence of lumbar stenosis superior to the expected affected level.

  6. Pre-operative assessment of relationship between inferior dental nerve canal and mandibular impacted third molar in Saudi population

    Directory of Open Access Journals (Sweden)

    S. Shujaat

    2014-07-01

    Conclusions: Our sample population most commonly exhibited horizontally angulated class I position B impactions of the mandible. The position of the ID canal significantly influenced the type of impaction and bone contact.

  7. canal24

    Data.gov (United States)

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

  8. 疑难根管再治疗中显微超声技术的临床应用%Root canal treatment of complicated anterior teeth with dental operating microscope and ultrasonic instru-ments

    Institute of Scientific and Technical Information of China (English)

    周艳; 秦念红; 徐铁华; 林爱娟

    2014-01-01

    目的:评价显微超声技术在疑难根管再治疗中的应用。方法:选取需要根管再治疗的前牙56颗,62个根管,在根管显微镜下,采用超声根管锉,顺利疏通根管后,常规完成根管预备和根管充填,观察并评价临床疗效。结果:62个根管中,疏通了21个钙化根管,取根管内断械6个,去除根管桩7个,寻找遗漏根管11个,修补根管侧壁穿孔6个,发现根管内吸收1个,根尖封闭10个,成功完成56颗患牙(62个根管)再治疗。结论:显微超声技术在疑难根管再治疗中可以提供有效的治疗手段,提高临床治疗成功率。%Objective:To evaluate the effect of dental operating microscope(DOM) and ultrasonic instruments in the management of complicated root canals. Method:56 teeth (62 root canals)that had been treated with convention repaired before were selected for root canal therapy. The root canal of all cases were retreated with ultrasonic instruments under den-tal operating microscope. The efficient of preparation and obturation was analyzed before and after treatment. Result:The 21 calcified root canals,6 canals blocked by instrument fragments,7 canals blocked by post,11 misunderstood root canals,6 canals side hole,1 root canal absorb inside,10 canals with open canal system were retreated successfully. Conclusion:The use of dental operating microscope and ultrasonic instruments is proved effective in complicated tooth root canal retreatment.

  9. 显微超声技术处理疑难根管的临床疗效分析%Evaluation of the clinical application of dental operating microscope and ultrasonic instruments in the management of complicated root canals

    Institute of Scientific and Technical Information of China (English)

    吴大明; 石炜; 梁睿贞; 吴锦涛; 刘卫红; 朱庆萍; 沈筱明

    2012-01-01

    Objective To evaluate the clinical application of the dental operating microscope ( DOM) and ultrasonic instruments in the management of complicated root canals. Methods 386 teeth with 625 root canals which could not be successfully managed by conventional methods received therapy with the DOM and ultrasonic instruments. The etiology of the canals included calcification,broken instruments,zinc phosphate cement, and resinifying materials,ledges,missed canals and canal perforations. Results 274 teeth were successfully managed with a success rate of 71.0%.473 canals were successfully managed with a success rate of 75.7%.The success rates of different categories of the complicated root canals were; 74.5% for calcified canals ,73.0% for canals blocked by broken instruments, 100.0% for canals blocked by zinc phosphate cement,77.3% for canals blocked by resinfying materials,72.0% for ledged canals ,82.1 % for missed canals and 72.7% for canal perforations. Conclusions The application of the DOM and ultrasonic instruments is proved to be an effective way in the management of complicated root canal therapy.%目的 评价牙科手术显微镜(Dental operating microscope,DOM)联合超声技术在疑难根管治疗中的临床应用效果.方法 选择因根管钙化、器械折断、根管内塑化物或锌汀、台阶、遗漏根管、根管壁侧穿等原因,无法进行常规根管治疗的患牙386颗,共625个根管,在DOM下联合超声技术进行治疗,分析疗效.结果 274颗患牙成功完成治疗,成功率为71.0%;473个根管成功完成治疗,成功率为75.7%.钙化根管的疏通率为74.5%,根管内折断器械的取出率为73.0%,根管内锌汀的去除率为100.0%,塑化根管的疏通率为77.3%,台阶的通过率为72.0%,遗漏根管的定位率为82.1%,根管壁侧穿的修补率为72.7%.结论 显微超声技术为疑难根管的治疗提供有效的解决方案.

  10. Clinical significance analysis of dental operating microscope reducing omission of molars root canal in elderly patients during the treatment of root canal%口腔显微镜对减少老年根管治疗期间磨牙根管遗漏的临床意义

    Institute of Scientific and Technical Information of China (English)

    李浩萍; 孟媛

    2015-01-01

    目的:探讨口腔显微镜对于减少老年根管治疗期间磨牙根管遗漏的临床意义。方法选取解放军第451医院2011年4月~2014年7月收治的接受根管治疗的老年患者184例,将其随机分为常规组和显微根管治疗组(DOM组),分别进行常规根管治疗和DOM根管治疗,对两组老年患者根管遗漏情况进行统计分析。对所有患者进行1年随访,观察老年患者的磨牙治疗及根管遗漏情况。结果常规组检出4根根管为14例(15.22%),与DOM组28例(30.43%)相比,差异有统计学意义(P<0.05);常规组检出5根根管0例(0.00%),与DOM组4例(4.35%)比较,差异有统计学意义(P<0.05)。常规组治疗失败6例(6.52%),DOM组治疗失败2例(2.17%),两组比较,差异有统计学意义(P<0.05)。结论应用DOM对老年磨牙患者进行根管治疗可有效减少磨牙根管遗漏率,值得临床推广使用。%Objective To discuss the clinical effect of dental operating microscope for reducing the omission of molars root canal in elderly patients during the treatment of root canal. Methods 184 cases of elderly patients who had re-ceived molars root canal treatment in the 451st Hospital of People's Liberation Army from April 2011 to July 2014 were selected. All the patients were divided into conventional group and DOM group, the conventional group was treat-ed with normal root canal therapy and the DOM group was treated with DOM root canal therapy. The incidence of root canal omission was analyzed. Then all the patients were followed up for 1 year, treatment of root canal and the inci-dence of root canal omission were observed. Results 14 cases of patients (15.22%) of the conventional group and 28 cases (30.43%) of the DOM group were detected with 4 root canals, which showed a statistically significant difference (P<0.05). None of the patients (0.00%) of conventional group and 4 cases (4.35%) of the DOM group were detected with 5 root canals, which showed a

  11. 下颌第二前磨牙3根管的显微根管治疗%Endodontic treatment of mandibular second premolar with three root canals using dental operating microscope:A case report

    Institute of Scientific and Technical Information of China (English)

    张中兴; 周琳

    2011-01-01

    下颌前磨牙根管形态复杂,变异较大,可能存在多根管,在治疗中极易遗漏.牙科手术显微镜可提供良好的光源及放大效果,使术者有可能在直视情况下对多根管下颌前磨牙进行有效的治疗.该文报道1例下颌前磨牙3根管的显微根管治疗.%Mandibular premolars are among the most difficult teeth to treat endoclontically because of variations in root canal anatomy.There are only a few endodontic publications citing the incidence of mandihular 2nd premolar with 3 root canals.Thorough knowledge of the basic root canal morphology as well as the possible anatomic variations is important for the successful treatment of such cases.This anicle describes the successful endodontic treatment of a mandibular 2nd premolar with 3 root canals treated with the help of operating microscope in a patient with more than two canals also in the contralateral side second premolar.

  12. Root canal irrigants

    OpenAIRE

    Kandaswamy Deivanayagam; Venkateshbabu Nagendrababu

    2010-01-01

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

  13. Canal Wall Reconstruction Mastoidectomy

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Objective To investigate the advantages of canal wall reconstruction (CWR) mastoidectomy, a single-stage technique for cholesteatoma removal and posterior external canal wall reconstruction, over the open and closed procedures in terms of cholesteatoma recurrence. Methods: Between June 2002 and December 2005, 38 patients (40 ears) with cholesteatoma were admited to Sun Yat-Sen Memorial Hospital and received surgical treatments. Of these patients, 25 were male with ages ranging between 11 and 60 years (mean = 31.6 years) and 13 were female with ages ranging between 20 and 65 years (mean = 38.8 years). Canal wall reconstruction (CWR)mastoidectomy was performed in 31 ears and canal wall down (CWD) mastoidectomy in 9 ears. Concha cartilage was used for ear canal wall reconstruction in 22 of the 31 CWR procedures and cortical mastoid bone was used in the remaining 9 cases. Results At 0.5 to 4 years follow up, all but one patients remained free of signs of cholesteatoma recurrence, i.e., no retraction pocket or cholesteatoma matrix. One patient, a smoker, needed revision surgery due to cholesteatoma recurrence 1.5 year after the initial operation. The recurrence rate was therefore 3.2% (1/31). Cholesteatoma recurrence was monitored using postoperative CT scans whenever possible. In the case that needed a revision procedure, a retraction pocket was identified by otoendoscopy in the pars flacida area that eventually evolved into a cholesteatoma. A pocket extending to the epitympanum filled with cholesteatoma matrix was confirmed during the revision operation, A decision to perform a modified mastoidectomy was made as the patient refused to quit smoking. The mean air-bone gap in pure tone threshold was 45 dB before surgery and 25 dB after (p < 0.05). There was no difference between using concha cartilage and cortical mastoid bone for the reconstruction regarding air-bone gap improvement, CT findings and otoendoscopic results. Conclusion CWR mastoidectomy can be used for

  14. 33 CFR 117.438 - Company Canal.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Company Canal. 117.438 Section 117.438 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Louisiana § 117.438 Company Canal. (a) The draw of...

  15. 精化程序,轻松操作--根管治疗新进展%Procedure refinement, easy operation--root canal treatment progress

    Institute of Scientific and Technical Information of China (English)

    樊明文

    2016-01-01

    Over the past ten years, with the progress of science and technology and improvement of equipment, the root canal treatment level has been promoted rapidly, and the root canal treatment effect has realized qualitative improve-ment. The 3 elements for the success of the root canal therapy which were the understanding of the root canal, sufficient preparation, close obturation were summarized and analyzed in this paper.%近十余年来,科学技术发展,设备器材更新,促进了根管治疗水平的迅速提高,使根管治疗效果实现了质的改进。本文就根管治疗成功3要素即认识根管、充分预备、严密充填进行了总结分析。

  16. El Canal del Atazar I

    Directory of Open Access Journals (Sweden)

    López de Berges y de los Santos, Emilio

    1967-03-01

    Full Text Available The Atazar Canal helps to supply Madrid with water, from the rivers Lozoya, Jarama and Sorbe. The section which operates at present starts at the Torrelaguna dam and finishes at the El Goloso reservoir. Later a further section will be added, from the Atazar dam, on the Lozoya river, to link up with the control dam at Torrelaguna. The canal capacity is 16 m3/sec, and it is 43.47 km long. It has a slope of 4/10.000. The cross section is similar to that of the Jarama canal, already built. There are interconnections between this canal and the Canal Alto, which previously supplied the high and medium part of Madrid. To overcome the ground unevenness 5 syphons have been built, the most important of which is the Colmenar Goloso syphon, which is 10.88 km in length. Construction commenced on December 10, 1962, and water reached Madrid on June 15th, 1966. The initial budget for this project was 1,500 million pesetas.El canal del Atazar refuerza considerablemente el abastecimiento de aguas a Madrid, procedentes de los ríos Lozoya, Jarama y, en un próximo futuro, del Sorbe. El tramo, actualmente en funcionamiento, empieza en el salto de Torrelaguna y finaliza en los depósitos de El Goloso. Más adelante se completará su trazado mediante un nuevo tramo que partirá del embalse de Atazar, en el Lozoya, para unirse al actual en el depósito regulador de Torrelaguna. Su capacidad es de 16 m3/s; su longitud, 43,471 km, y su pendiente, 4 diezmilésimas. La sección tipo es análoga a la del canal del Jarama, de construcción anterior. Mediante la oportuna obra de transvase se realizan intercambios entre este Canal y el Canal Alto que abastecía anteriormente la parte media y alta de la capital. Para salvar los desniveles del terreno se han construido 5 sifones, siendo el más importante el de Colmenar-Goloso, con una longitud de 10,8S4 km. El comienzo de las obras tuvo lugar el 10 de diciembre de 1962, y el agua llegó a Madrid el 15 de junio de 1966. Su

  17. [Frequency and most common localisation of root canal curvature].

    Science.gov (United States)

    Blasković-Subat, V

    1991-01-01

    The root canal therapy of the curved canals is a complex operative procedure. Therefore 260 root canals were analysed radiologically to determine the frequency and the most common localisation of the root canal curvature. The frequency of the curved canals averaged at 59%, being greater in the sample of posterior than in the anterior teeth (p less than 0.05). The root canal curvature was most frequently localised at the apical third part (53.9%), followed by the cervical (33.3%) and the middle (12.8%) third part. The apical curvature was predominant in the sample of the anterior, while the cervical predominant (45.2%) in the sample of the posterior teeth. This study pointed out that the frequency of the curved canals is rather high. Consequently, the necessity for practising the modern root canal preparation techniques, bearing in mind their potential danger, is emphasized. PMID:1819932

  18. Application of dental operating microscope and ultrasonic instruments in treatment of mesiobuccal root canal of maxillary first permanent molar%上颌第一磨牙近颊第二根管的显微超声治疗

    Institute of Scientific and Technical Information of China (English)

    刘勇; 张文奎; 张皑峰

    2011-01-01

    Objective To observe the effect of the dental operating microscope (DOM) and the ultrasonic instruments in the treatment of the mesiobuccal root canal of the maxillary first permanent molar. Methods The pulp chambers were opened and the second mesiobuccal root canals (MB2) were explored in 112 maxillary first permanent molar. MB2, not found under naked eyes, was explored with DOM and ultrasonic technique. Results The detection rate of MB2 with naked eyes was 32. 1%. The rate was 75.9% by using DOM and ultrasonic instruments. Conclusions It is helpful to find some invisible orifice of MB2 using DOM and ultrasonic technique, and it would be beneficial to improve the root canal therapy.%目的 探讨显微超声技术在在治疗上颌第一恒磨牙近颊根管的应用.方法 以112颗上颌第一恒磨牙为研究对象,开髓后探查近颊第二根管(second mesiobuccal root canal,MB2),未能发现MB2者在牙科手术显微镜下(dental operating microscope,DOM)采用超声技术探查MB2根管口.结果 上颌第一恒磨牙近颊第二根管肉眼下探查发现率为32.1%,使用显微镜后MB2的发现率为75.9%.结论 显微超声技术有助于发现较隐匿的MB2根管口,对于完善根管治疗具有较大临中床意义.

  19. The Dehiscent Facial Nerve Canal

    Directory of Open Access Journals (Sweden)

    Sertac Yetiser

    2012-01-01

    Full Text Available Accidental injury to the facial nerve where the bony canal defects are present may result with facial nerve dysfunction during otological surgery. Therefore, it is critical to know the incidence and the type of facial nerve dehiscences in the presence of normal development of the facial canal. The aim of this study is to review the site and the type of such bony defects in 144 patients operated for facial paralysis, myringoplasty, stapedotomy, middle ear exploration for sudden hearing loss, and so forth, other than chronic suppurative otitis media with or without cholesteatoma, middle ear tumors, and anomaly. Correlation of intraoperative findings with preoperative computerized tomography was also analyzed in 35 patients. Conclusively, one out of every 10 surgical cases may have dehiscence of the facial canal which has to be always borne in mind during surgical manipulation of the middle ear. Computerized tomography has some limitations to evaluate the dehiscent facial canal due to high false negative and positive rates.

  20. Root canal irrigants

    Directory of Open Access Journals (Sweden)

    Kandaswamy Deivanayagam

    2010-01-01

    Full Text Available 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.

  1. Panama Canal Watershed Experiment- Agua Salud Project

    Science.gov (United States)

    Stallard, Robert F.; Ogden, Fred L.; Elsenbeer, Helmut; Hall, Jefferson S.

    2010-01-01

    The Agua Salud Project utilizes the Panama Canal’s (Canal) central role in world commerce to focus global attention on the ecosystem services provided by tropical forests. The Canal was one of the great engineering projects in the world. Completed in 1914, after almost a decade of concerted effort, its 80 km length greatly shortened the voyage between the Atlantic and Pacific Oceans. An entire class of ships, the Panamax, has been constructed to maximize the amount of cargo that can be carried in a Canal passage. In today’s parlance, the Canal is a “green” operation, powered largely by water (Table 1). The locks, three pairs on each end with a net lift of 27 meters, are gravity fed. For each ton of cargo that is transferred from ocean to ocean, about 13 tons of water (m3) are used. Lake Gatún forms much of the waterway in the Canal transect. Hydroelectricity is generated at the Gatún dam, whenever there is surplus water, and at Madden Dam (completed in 1936) when water is transferred from Lake Alhajuela to Lake Gatún. The Canal watershed is the source of drinking water for Panama City and Colon City, at either end of the Canal, and numerous towns in between.

  2. The Root Canal Biofilm

    NARCIS (Netherlands)

    Sluis, van der L.W.M.; Boutsioukis, C.; Jiang, L.M.; Macedo, R.; Verhaagen, B.; Versluis, M.; Chávez de Paz, E.; Sedgley, C.M.; Kishen, A.

    2015-01-01

    The aims of root canal irrigation are the chemical dissolution or disruption and the mechanical detachment of pulp tissue, dentin debris and smear layer (instrumentation products), microorganisms (planktonic or biofilm), and their products from the root canal wall, their removal out of the root cana

  3. Root canal irrigation

    NARCIS (Netherlands)

    L. van der Sluis; C. Boutsioukis; L.M. Jiang; R. Macedo; B. Verhaagen; M. Versluis

    2015-01-01

    The aims of root canal irrigation are the chemical dissolution or disruption and the mechanical detachment of pulp tissue, dentin debris and smear layer (instrumentation products), microorganisms (planktonic or biofilm), and their products from the root canal wall, their removal out of the root cana

  4. Three root canals in the maxillary second premolar

    Directory of Open Access Journals (Sweden)

    de Almeida-Gomes Fabio

    2009-01-01

    Full Text Available In this study, we report an endodontic treatment of the maxillary second premolar with three root canals and distinct foramens. The possibility of three root canals in this tooth is quite small; however, it must be taken into account in clinical and radiographic evaluation during endodontic treatment. Many times, their presence is noticed only after canal treatment due to continuing post-operative discomfort.

  5. Feasibility and limitations of endoscopy in Guyon's canal

    OpenAIRE

    Noszczyk, Bartłomiej H.; Zdybek, Piotr

    2014-01-01

    Introduction This retrospective report summarizes observations from eight operations where the endoscopically assisted approach was used to explore Guyon's canal syndromes of idiopathic aetiology. Aim To evaluate the feasibility and limitations of endoscopic Guyon's canal release performed from a distal forearm incision. Material and methods Eight charts and video records of eight ulnar tunnel syndrome patients presenting concomitant idiopathic Guyon's canal syndromes were retrospectively rev...

  6. Role of sediment transport in operation and maintenance of supply and demand based irrigation channels : application to Machai Maira Branch canals

    OpenAIRE

    Munir, S.

    2011-01-01

    Like in many emerging and least developed countries, agriculture is vital for Pakistan’s national economy. It contributes 21% to the annual gross domestic product (GDP), engages 44% of total labour force and contributes 60% to the national export. Pakistan has a total area of 80 Mha (million hectares) with 22 Mha arable land, out of which 17 Mha is under irrigation, mostly under canal irrigation. Due to the arid to semi-arid climate, the irrigation is predominantly necessary for successful cr...

  7. Design of canals

    CERN Document Server

    Swamee, P K

    2015-01-01

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

  8. Determining optimal transit charges: The Kiel Canal in Germany

    OpenAIRE

    Heitmann, Nadine; Rehdanz, Katrin; Schmidt, Ulrich

    2011-01-01

    The Kiel Canal in Germany connects ports on the Baltic Sea with the rest of the world and is the most-used artificial waterway in the world. Despite this fact, it generates a balance sheet loss. Revenues, which are mainly generated by the transit charge, do not cover its operating expenses. This situation raises the question: What reforms could be made to make the canal generate a balance sheet profit? In this paper, we focus solely on the canal's revenue. Because the canal is a monopoly that...

  9. Endodontic management of a mandibular first molar with six root canal systems.

    Science.gov (United States)

    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. PMID:26430309

  10. MIMO LPV State-Space Identification of Open-Flow Irrigation Canal Systems

    Directory of Open Access Journals (Sweden)

    Yolanda Bolea

    2012-01-01

    Full Text Available Canal systems are complex nonlinear, distributed parameter systems with changing parameters according to the operating point. In this paper, a linear parameter-varying (LPV state-space canal control model is obtained by identification in a local way using a multimodel approach. This LPV identification procedure is based on subspace methods for different operating points of an irrigation canal covering the full operation range. Different subspace algorithms have been used and compared. The model that best represents the canal behavior in a precise manner has been chosen, and it has been validated by error functions and analysis correlation of residuals in a laboratory multireach pilot canal providing satisfactory results.

  11. The fluid mechanics of root canal irrigation.

    Science.gov (United States)

    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

  12. The fluid mechanics of root canal irrigation

    International Nuclear Information System (INIS)

    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

  13. Canals, River Irrigation Company Canal, Published in 2002, Duchesne County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Canals dataset, was produced all or in part from Other information as of 2002. It is described as 'River Irrigation Company Canal'. Data by this publisher are...

  14. Canals, Lake Canal, Published in 2002, Duchesne County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Canals dataset, was produced all or in part from Other information as of 2002. It is described as 'Lake Canal'. Data by this publisher are often provided in...

  15. Canals, Yellowstone Feeder Canal, Published in 2002, Duchesne County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Canals dataset, was produced all or in part from Other information as of 2002. It is described as 'Yellowstone Feeder Canal'. Data by this publisher are often...

  16. Canals, Bypass Canal, Published in 2002, Duchesne County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Canals dataset, was produced all or in part from Other information as of 2002. It is described as 'Bypass Canal'. Data by this publisher are often provided in...

  17. Shaping ability of the M4 handpiece and Safety Hedstrom files in simulated root canals.

    Science.gov (United States)

    Lloyd, A; Jaunberzins, A; Dhopatkar, A; Bryant, S; Dummer, P M

    1997-01-01

    The aim of this study was to assess the shaping ability of the M4 reciprocating handpiece and Safety Hedstrom files in simulated canals. A total of 40 simulated canals of various angles and positions of curvature were prepared with an M4 handpiece using Safety Hedstrom files oriented with the ground, flattened surface towards the inner aspect of the curve. A standard regimen was adopted throughout. Pre- and post-operative longitudinal images of the canals were taken with a video camera and stored and manipulated in a computer with image analysis software. The presence of canal aberrations and the amount and location of resin material removed as a result of preparation were determined from composite images of superimposed pre- and post-operative views. Preparation time varied significantly (P canal types; overall, 20 degrees canals were prepared more quickly than 40 degrees canals. Zips and elbows were observed in 16 out of the 40 canals with most (11) being created in 40 degrees specimens. Ledges were found in 19 canals and perforations in only 1. There were no significant differences between canal shapes for these aberrations. Excessive removal of material from the inner aspect of the canal at the curve to create a danger zone was found in 20 canals, but only in those with 40 degrees curves. Significant differences in total canal width between the canal types were seen at the zips (P danger zones (P danger zones varied significantly (P canal types. Under the conditions of this study, the M4 handpiece and Safety Hedstrom files created hour-glass preparations in a substantial proportion of canals. In reality, the Safety Hedstrom file with its one flattened surface was ineffective at reducing removal of material along the inner aspect of canal curves in severely curved specimens and clearly has the potential to create strip perforations in teeth. PMID:9477790

  18. Ear canal cholesteatoma.

    Science.gov (United States)

    Holt, J J

    1992-06-01

    Although cholesteatomas are more commonly found in the middle ear and the mastoid, the disease can occur in the external ear canal. All cases of ear canal cholesteatoma treated by the author were reviewed. There were nine ears in seven patients, who had an average age of 62 years. The lesions ranged in size from a few millimeters to extensive mastoid destruction. Smaller lesions can be managed by frequent cleaning as an office procedure. Larger lesions require surgery, either canaloplasty or mastoidectomy. The otolaryngologist should suspect this disease in the elderly. Microscopic examination of the ear with meticulous cleaning of all wax, especially in elderly patients, is most useful in detecting early disease. Frequent applications of mineral oil to the canal should be used in the management of the disease and to prevent recurrence. PMID:1376388

  19. Love canal questions

    Science.gov (United States)

    Bell, Peter M.

    The Environmental Protection Agency (EPA) conducted a 3-month monitoring study of the Love Canal area near Niagara Falls, N.Y., after the federal government pronounced that a potential health risk existed due to chemical waste dumps. In 1982 the Department of Health and Human Services (HHS) decided that the area was habitable, subject to implementation of effective safeguards against leakage from the canal and to cleaning up of the contaminants. Now, the Congressional Office of Technology Assessment (OTA) has announced that, with the information available, it is not possible to demonstrate with certainty that unsafe levels do not exist within the so-called “emergency declaration area” (EDA).

  20. Functional outcome of surgical management of degenerative lumbar canal stenosis

    Directory of Open Access Journals (Sweden)

    Rajendra Nath

    2012-01-01

    Conclusion: Operative treatment in patients of degenerative lumbar canal stenosis yields excellent results as observed on the basis of JOA scoring system. No patient got recurrence of symptoms of nerve compression.

  1. A Clinical Update on the Different Methods to Decrease the Occurrence of Missed Root Canals

    Science.gov (United States)

    Mohammadi, Zahed; Asgary, Saeed; Shalavi, Sousan; V. Abbott, Paul

    2016-01-01

    One of the main causes of endodontic treatment failure is the clinician’s inability to localize all the root canals. Due to the complex anatomy of the root canal system, missed canals are not uncommon. There are several strategies to decrease the possibility of missed root canals starting with good pre-operative radiographies. In order to overcome the limitations of conventional radiographies, cone-beam computed tomography (CBCT) can be considered. A correct access cavity preparation is of pivotal importance in localizing the orifices of the root canals. Furthermore, ultrasonics are very important devices to find missed canals. Increasing magnification and illumination enhance the possibility of finding all root canals during root canal treatment. The purpose of the present paper was to review all of the above techniques and devices. PMID:27471533

  2. A maxillary central incisor with four root canals

    Directory of Open Access Journals (Sweden)

    Fábio de Almeida-Gomes

    2012-01-01

    Full Text Available The objective of the present study is to present a case report of endodontic treatment of a maxillary central incisor with 1 root and 4 root canals. The success of endodontic treatment requires knowledge of dental anatomy and its variations. This clinical article reports an unusual anatomy detected in a maxillary central incisor with 4 root canals with an associated periapical lesion. The incidence of 4 root canals in this tooth is rare. However, it must be taken into consideration, the clinical and radiographic evaluations during the endodontic treatment in order to enhance the diagnostic. Many times, the presence of a supernumerary canal is noticed only after canal treatment due to continuing post-operative discomfort or treatment failure.

  3. MIMO LPV state-space identification of open-flow irrigation canal systems

    OpenAIRE

    Yolanda Bolea; Nicolas Chefdor; Antoni Grau

    2012-01-01

    Canal systems are complex nonlinear, distributed parameter systems with changing parameters according to the operating point. In this paper, a linear parameter-varying (LPV) state-space canal control model is obtained by identification in a local way using a multimodel approach. This LPV identification procedure is based on subspace methods for different operating points of an irrigation canal covering the full operation range. Different subspace algorithms have been used and compared. The mo...

  4. Curved canals: Ancestral files revisited

    Directory of Open Access Journals (Sweden)

    Jain Nidhi

    2008-01-01

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

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

    Science.gov (United States)

    Langbein, Walter Basil

    1976-01-01

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

  6. Facial Canal Dehiscence in Patients with Chronic Otitis Surgery

    Directory of Open Access Journals (Sweden)

    Ahmet Uluat

    2016-04-01

    Full Text Available Aim: To examine facial canal status in patients with chronic otitis media (COM surgery and to detect the relation between facial canals dehiscence (FCD with middle ear pathology in these patients. Material and Method: The surgery data of patients who were subjected to tympanoplasty with or without mastoidectomy and radical mastoidectomy due to COM were analyzed retrospectively from January 2006 to December 2012. In addition to demonstrative data of the patients, status of facial canal and preoperative diagnoses of patients, type of the operation performed, status of middle ear, number of surgeries, existence of cholesteatoma, existence of ossicular chain defect, lateral canal defect and dura defect were assessed and the relation thereof with facial canal dehiscence (FCD was analyzed statistically. Results: Seven hundred ninety six patients were included in the study. FCD was detected in 10.05% of the patients. FCD was most frequently observed in the tympanic segment. It was found out that there was a statistically significant relationship of middle ear pathology, cholesteatoma, revision surgery, lateral semicircular canal and ossicular chain defect with FCD. Discussion: COM diagnosed patients may have defect in facial canal according to their preoperative diagnoses, middle ear pathologies, number of operations and ossicular chain defects. These patients should be applied a more careful surgery and closely followed up in postoperative periods.

  7. Comparison of two endodontic handpieces during the preparation of simulated root canals.

    Science.gov (United States)

    Smith, R B; Edmunds, D H

    1997-11-01

    The objective of this in vitro study was to compare and assess two endodontic handpieces during the preparation of simulated root canals. One hundred and sixty simulated root canals in clear resin blocks, of two angles and positions of curvature, were prepared using either Shaper files activated by the MM1500 Sonic Air handpiece (Micro-Mega, Besançon, France) or Excalibur files activated by the W & H Excalibur 969 handpiece (W & H, Bürmoos, Austria). Files of 21-mm or 25-mm length were used. When preparing the canals, the files were used either in line with or perpendicular to the canal curvature. Preparation of the canals was carried out using a technique described in the manufacturers' literature. A variety of parameters were used to compare the handpieces, including an assessment of the canal preparation time, the deformation or fracture of instruments, loss of canal length, weight loss from the resin blocks and the overall postpreparation canal shape. Both handpieces provided an efficient and easy method of preparing and shaping the root canal with little operator fatigue. The MM1500 Sonic Air handpiece took significantly more time (P canals and was associated with both more loss of working length (P canals. The MM1500 Sonic Air handpiece created significantly more aberrations than the Excalibur handpiece (P danger zone and coronal narrow). The effects of the variables, canal curvature, file length and the plane of use of the file, on the performance of the handpieces, were also assessed. PMID:9588976

  8. Managing curved canals

    Directory of Open Access Journals (Sweden)

    Iram Ansari

    2012-01-01

    Full Text Available Dilaceration is the result of a developmental anomaly in which there has been an abrupt change in the axial inclination between the crown and the root of a tooth. Dilaceration can be seen in both the permanent and deciduous dentitions, and is more commonly found in posterior teeth and in maxilla. Periapical radiographs are the most appropriate way to diagnose the presence of root dilacerations. The controlled regularly tapered preparation of the curved canals is the ultimate challenge in endodontics. Careful and meticulous technique will yield a safe and sufficient enlargement of the curved canals. This article gives a review of the literature and three interesting case reports of root dilacerations.

  9. Effect of root canal filling with warm vertical condensation under dental operating microscope%根管显微镜下应用连续波热垂直加压技术充填根管的疗效分析

    Institute of Scientific and Technical Information of China (English)

    薛明; 詹福良; 于静涛; 仇丽鸿

    2011-01-01

    PURPOSE: To evaluate the clinical effect of root canal filling with warm vertical condensation with or without dental operating microscope.METHODS: Fifty maxillary anterior teeth with single, straight canals were divided into two groups.Each tooth was instrumented by X-Smart rotary nickel-titanium files to a master file 0.06 taper F3, root canal in the group 1 was obturated with warm vertical condensation using system B for downpack and Obtura Ⅱ for backfilling without dental operating microscope; root canal in the group 2 was obturated using the same methods under the dental operating microscope.The effect of quality of root canal filling was evaluated by X-ray radiograph post-operatively and after two years of treatment.SPSS10.0 software package was used for Chi-square test.RESULTS: Significant difference was found between the two groups on the quality of root canal filling post-operatively (P<0.05),with better quality of root canal filling in the group using dental operating microscope, no significant difference was found between the two groups after two years (P>0.05).CONCLUSIONS: Warm vertical condensation under the dental operating microscope is a good method for root canal filling.It may improve the quality of root canal filling effectively, and therefore, worthy of clinical application.%目的:评价根管显微镜下应用连续波热牙胶垂直加压技术行根管充填的临床疗效.方法:选择上颌前牙单、直根管患牙50颗为研究对象,采用ProTaper机用镍钛锉预备至F3锉,随机分为2组,每组25颗患牙.分别采用常规方法和显微镜下连续波热垂直加压技术充填根管.应用术后即刻X线片和术后2年X线片分别进行2组患牙根管充填质量和术后2年的临床疗效比较,采用SPSS10.0软件包进行统计学分析,充填质量和临床疗效比较采用χ2检验.结果:根管显微镜下操作的充填质量高于常规充填操作(P<0.05).术后2年复查显示,显微镜下操作的根

  10. Bundling ecosystem services in the Panama Canal watershed

    OpenAIRE

    Simonit, Silvio; Perrings, Charles

    2013-01-01

    Land cover change in watersheds affects the supply of a number of ecosystem services, including water supply, the production of timber and nontimber forest products, the provision of habitat for forest species, and climate regulation through carbon sequestration. The Panama Canal watershed is currently being reforested to protect the dry-season flows needed for Canal operations. Whether reforestation of the watershed is desirable depends on its impacts on all services. We develop a spatially ...

  11. Controversy at Love Canal.

    Science.gov (United States)

    Paigen, B

    1982-06-01

    A cancer researcher reviews the events surrounding the toxic waste contamination at Love Canal with emphasis on the political nature of the controversy about its health impact. Antagonism between the community and the New York State Department of Health was fueled by several factors: the state's awareness that it gained from delay in investigation, disagreement on health problems to be studied, control over the information gathering process, silencing of opposition opinion, and the violation of norms of scientific behavior. The author calls for the establishment of standards of ethical behavior for scientists in such situations, standards for conflict resolution, and means of appeal for those injured.

  12. Spinal canal stenosis; Spinalkanalstenose

    Energy Technology Data Exchange (ETDEWEB)

    Papanagiotou, P.; Boutchakova, M. [Klinikum Bremen-Mitte/Bremen-Ost, Klinik fuer Diagnostische und Interventionelle Neuroradiologie, Bremen (Germany)

    2014-11-15

    Spinal stenosis is a narrowing of the spinal canal by a combination of bone and soft tissues, which can lead to mechanical compression of spinal nerve roots or the dural sac. The lumbal spinal compression of these nerve roots can be symptomatic, resulting in weakness, reflex alterations, gait disturbances, bowel or bladder dysfunction, motor and sensory changes, radicular pain or atypical leg pain and neurogenic claudication. The anatomical presence of spinal canal stenosis is confirmed radiologically with computerized tomography, myelography or magnetic resonance imaging and play a decisive role in optimal patient-oriented therapy decision-making. (orig.) [German] Die Spinalkanalstenose ist eine umschriebene, knoechern-ligamentaer bedingte Einengung des Spinalkanals, die zur Kompression der Nervenwurzeln oder des Duralsacks fuehren kann. Die lumbale Spinalkanalstenose manifestiert sich klinisch als Komplex aus Rueckenschmerzen sowie sensiblen und motorischen neurologischen Ausfaellen, die in der Regel belastungsabhaengig sind (Claudicatio spinalis). Die bildgebende Diagnostik mittels Magnetresonanztomographie, Computertomographie und Myelographie spielt eine entscheidende Rolle bei der optimalen patientenbezogenen Therapieentscheidung. (orig.)

  13. Deadbands and the Dynamic Response and Performance of Large Water Transfer Canal System

    Institute of Scientific and Technical Information of China (English)

    DING Zhiliang; WANG Changde; TAN Guangming; GUAN Guanghua

    2009-01-01

    An operating simulation mode for multireach canal system in series under gate regulating is established. The discharge feedforward plus water lever feedback PID controller was adopted. And the performance indicators are introduced to evaluate the control effects of canal operation. Influence on dynamic response process and dynamic performance as well as the control actions of canal system are studied according to the variation of the gate deadband and water level deadband. The results showed that the larger the gate deadband, the worse, the control effect of canal system over water level, and so done the stable process of gate discharge, yet the stable process of gate opening was getting better, while the upstream gate regulation of each canal pool was less at the time when canal stabilizes;the closer to downstream end of canal, the lager steady-state error of this canal pool was, and the lager influence of gate deadband on the steady-state error as well as response time of this canal pool was;the canal system can not acquire superiority in both the control performance and control actions when only the water level deadband was established.

  14. Endoscopic posterior decompression of lumbar canal stenosis

    Directory of Open Access Journals (Sweden)

    Yad Ram Yadav

    2013-01-01

    Full Text Available Lumbar canal stenosis (LCS is quite common. Surgery is indicated when patient fails to improve after conservative treatment. Endoscopic technique can be used in LCS and lateral recess stenosis. It can be performed in degenerative canal stenosis or with disc bulges. Bilateral severe bony canal stenosis and unstable spine are the contraindications. This procedure should be avoided in patients with a history of trauma. Detailed history and thorough physical examination should be performed to find out exact level of pathology responsible for symptoms. Patient′s symptoms must correlate with radiological findings. Magnetic resonance imaging is the investigation of choice because of its superior visualization of soft-tissue. Computed tomography scan does give a more accurate and detailed picture of the bony anatomy. Although the operative time and the complication rate could be more in the initial learning curve, the results of endoscopic decompression are comparable with conventional open procedures with the additional benefit of decreased complications and lower morbidity, when sufficient experience is gained. Complications in endoscopic surgery for LCS could be dural tears, hematomas and root and facet injury. This procedure is also associated with limitations such as steep learning curve and the contra lateral decompression may not be as good as ipsilateral side. Some of the limitations of this technique can be overcome by attending live operative workshop, practice on models and hands on cadaveric dissection. Conversion to an open procedure may be required when there is disorientation, management of dural tear and for control of bleeding.

  15. Shaping ability of Quantec Series 2000 rotary nickel-titanium instruments in simulated root canals: Part 2.

    Science.gov (United States)

    Thompson, S A; Dummer, P M

    1998-07-01

    The aim of this laboratory based study was to determine the shaping ability of Quantec Series 2000 nickel-titanium rotary instruments in simulated root canals. A total of 40 canals with four different shapes in terms of angle and position of curve were prepared with Quantec Series 2000 instruments using the technique recommended by the manufacturer. Part 2 of this report describes the efficacy of the instruments in terms of prevalence of canal aberrations, the amount and direction of canal transportation and overall post-operative shape. Pre- and post-operative images of the canals were taken using a video camera attached to a computer with image analysis software. The pre- and post-operative views were superimposed to highlight the amount and position of material removed during preparation. Twenty-one zips and elbows were created during preparation with a significant difference (P canal shapes in terms of the incidence of aberrations. Four perforations were created, with significant differences (P canal shapes; three ledges were also created but no danger zones. Highly significant differences (P canal shapes in total canal width at specific points along the canal length and in the amount of resin removed from the inner and outer aspects of the curve. Canal transportation at the end-point of preparation was most frequently directed towards the outer aspect of the curve, and without exception in canals with 40 degrees curves. At the beginning of the curve, transportation became more evenly balanced between the inner and outer aspect of the curve, although predominated towards the outer. Transportation was generally directed towards the outer at the orifice, especially in canals with 40 degrees curves. Mean absolute transportation at the various measurement points was less than 0.11 mm; significant differences occurred between canal shapes at the end-point of preparation (P canals. PMID:9823116

  16. Hood Canal Steelhead - Hood Canal Steelhead Supplementation Experiment

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Hood Canal Steelhead Project is a 17-year before-after-control-impact experiment that tests the effects of supplementation on natural steelhead populations in...

  17. Method for Constructing Standardized Simulated Root Canals.

    Science.gov (United States)

    Schulz-Bongert, Udo; Weine, Franklin S.

    1990-01-01

    The construction of visual and manipulative aids, clear resin blocks with root-canal-like spaces, for simulation of root canals is explained. Time, materials, and techniques are discussed. The method allows for comparison of canals, creation of any configuration of canals, and easy presentation during instruction. (MSE)

  18. CT findings of the osteoma of the external auditory canal

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ha Young; Song, Chang Joon; Yoon, Chung Dae; Park, Mi Hyun; Shin, Byung Seok [Chungnam National University, School of Medicine, Daejeon (Korea, Republic of)

    2006-07-15

    We wanted to report the CT image findings of the osteoma of the external auditory canal. Temporal bone CT scanning was performed on eight patients (4 males and 4 females aged between 8 and 41 years) with pathologically proven osteoma of the external auditory canal after operation, and the findings of the CT scanning were retrospectively reviewed. Not only did we analyze the size, shape, distribution and location of the osteomas, we also analyzed the relationship between the lesion and the tympanosqumaous or tympanomastoid suture line, and the changes seen on the CT scan images for the patients who were able to undergo follow-up. All the lesions of the osteoma of the external auditory canal were unilateral, solitary, pedunculated bony masses. In five patients, the osteomas occurred on the left side and for the other three patients, the osteomas occurred on the right side. The average size of the osteoma was 0.6 cm with the smallest being 0.5 cm and the largest being 1.2 cm. Each of the lesions was located at the osteochondral junction in the terminal part of the osseous external ear canal. The stalk of the osteoma of the external auditory canal was found to have occurred in the anteroinferior wall in five cases (63%), in the anterosuperior wall (the tympanosqumaous suture line) in two cases (25%), and in the anterior wall in one case. The osteoma of the external auditory canal was a compact form in five cases and it was a cancellous form in three cases. One case of the cancellous form was changed into a compact form 35 months later due to the advanced ossification. Osteoma of the external auditory canal developed in a unilateral and solitary fashion. The characteristic image findings show that it is attached to the external auditory canal by its stalk. Unlike our common knowledge about its occurrence, osteoma mostly occurred in the tympanic wall, and this is regardless of the tympanosquamous or tympanomastoid suture line.

  19. Kyphoplasty for osteoporotic fractures with spinal canal compromise

    International Nuclear Information System (INIS)

    Objective: To explore the feasibility and clinical outcome of kyphoplasty in the treatment of osteoporotic fractures with canal compromise. Methods: A total of 16 patients with osteoporotic fractures with canal compromise without neurological deficit were attempted to be treated by kyphoplasty. During kyphoplasty, modified techniques including staged bone cement injection and dynamic fluoroscopic monitoring were used. Pain was measured using the self-reporting Visual Analogue pain Scale (VAS) preoperatively, postoperatively and in the final follow-up. Disability was measured using the Oswestry Disability questionnaire (ODI) preoperatively, postoperatively and in the final follow-up. The height of the compromised vertebral body, the kyphotic angle and the spinal canal compromise were measured preoperatively, postoperatively and in the final follow-up. Results: Operations were completed smoothly, with the exception of one patient with less cement leakage but without clinical symptom occurred. Relief of pain was achieved after kyphoplasty. The mean VAS score of these patients decreased from 8.1 ± 1.2 pre-operatively to 2.7 ± 0.6 post-operatively (P0.05). In the final follow-up, the spinal canal compromise was (14.4 ± 3.1)%. Conclusion: Kyphoplasty is a relatively safe and effective method for the treatment of osteoporotic fractures with canal compromise without neurological deficit. (authors)

  20. Extracting Environmental Benefits from a New Canal in Nicaragua: Lessons from Panama.

    Directory of Open Access Journals (Sweden)

    Richard Condit

    2015-07-01

    Full Text Available Biologists have raised objections to a new canal in Nicaragua, but in this Essay I argue that dire predictions of environmental catastrophe are exaggerated. I present an alternative view based on my research experience in Panama, where Canal operations foster forest conservation. Currently in Nicaragua, the rate of forest loss is so rapid that the canal cannot make it worse. Rather, I contend, adoption of international standards in canal construction could lead to net environmental and social benefits for the country.

  1. Endodontic management of a mandibular first molar with six root canal systems

    Directory of Open Access Journals (Sweden)

    Dilip Jain

    2015-01-01

    Full Text Available 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.

  2. The Love Canal: Beyond science?

    Science.gov (United States)

    Bell, Peter M.

    When in 1978, the New York State Department of Health issued the report, ‘Love Canal—Public Health Time Bomb,’ the serious effects of chemical waste contamination in the Love Canal area became an issue of national concern. A few ‘studies’ since then have produced results in concert with those of initial reports that described ‘conditions of acute health effects’ as being linked to hazardous wastes incorporated in landfill in the Love Canal site near Niagara Falls, New York. Now that a ‘blue ribbon’ panel of experts from the medical sciences has reviewed the problems of Love Canal, however, a different view has emerged. The ‘Report of the Governors' Panel to Review Scientific Studies and the Development of Public Policy on Problems Resulting from Hazardous Wastes,’ transmitted in October of this year, identifies the following factors about the health effects at Love Canal:

  3. Ultrasonic cleaning of root canals

    Science.gov (United States)

    Verhaagen, Bram; Boutsioukis, Christos; Jiang, Lei-Meng; Macedo, Ricardo; van der Sluis, Luc; Versluis, Michel

    2011-11-01

    A crucial step during a dental root canal treatment is irrigation, where an antimicrobial fluid is injected into the root canal system to eradicate all bacteria. Agitation of the fluid using an ultrasonically vibrating miniature file has shown significant improvement in cleaning efficacy over conventional syringe irrigation. However, the physical mechanisms underlying the cleaning process, being acoustic streaming, cavitation or chemical activity, and combinations thereof, are not fully understood. High-speed imaging allows us to visualize the flow pattern and cavitation in a root canal model at microscopic scales, at timescales relevant to the cleaning processes (microseconds). MicroPIV measurements of the induced acoustic streaming are coupled to the oscillation characteristics of the file as simulated numerically and measured with a laser vibrometer. The results give new insight into the role of acoustic streaming and the importance of the confinement for the cleaning of root canals.

  4. Comparison of two stainless steel files to shape simulated root canals.

    Science.gov (United States)

    al-Omari, M A; Bryant, S; Dummer, P M

    1997-01-01

    The aim of this study was to compare the shaping ability of two stainless steel files using simulated canals. A total of 80 simulated canals of various angles and positions of curvature were prepared by hand using either Mani K-Files or Micro Mega K-Files. Following orifice enlargement each file type was used to prepare 40 canals employing a linear filing motion and an anticurvature stepback technique. Pre- and post-operative longitudinal images of the canals were taken with a video camera and stored and manipulated in a computer with image analysis software. The presence of canal aberrations and the amount of material removed as a result of preparation were determined from composite images of superimposed pre- and post-operative views. Overall, canal preparation with Mani K-Files was significantly quicker (P danger zones. Micro Mega K-Files created significantly wider (P Canal shape had a significant influence on preparation time (P danger zones (P canals with better shapes. Original canal shape had a substantial influence on the outcome of shaping procedures. PMID:9477792

  5. Horizontal Canal Benign Positional Vertigo

    Directory of Open Access Journals (Sweden)

    Mohtaram Najafi

    1998-03-01

    Full Text Available Benign paroxysmal positional vertigo (BPPV is a syndrome characterized by transient episodes of vertigo in association with rapid changes in head position in Dix-Halpike Maneuver. This kind of vertigo is thought to be caused by migration of otoconial debris into canals other than the posterior canal, such as the anterior or lateral canals. It is also theoretically possible for many aberrant patterns of BPPV to occur from an interaction of debris in several canals, location of debris within the canal, and central adaptation patterns to lesions. The symptoms of BPPV are much more consistent with free-moving densities (canaliths in the posterior SCC rather than fixed densities attached to the cupula. While the head is upright, the particles sit in the PSC at the most gravity-dependent position. The best method to induce and see vertigo and nystagmus in BPPV of the lateral semicircular canal is to rotate head 90°while patient is in the supine position, nystagmus would appear in the unaffected side weaker but longer than the affected side. canal paresis has been described in one third of the patients with BPPV. Adaptation which is one of the remarkable features of BPPV in PSC is rarely seen in LSC. Rotations of 270° or 360° around the yaw axis (the so-called barbecue maneuver toward the unaffected ear are popular methods for the treatment of geotropic HC-BPPV. These maneuvers consist of sequential head turning of 90° toward the healthy side while supine. With these maneuvers, the free-floating otoconial debris migrates in the ampullofugal direction, finally entering the utricle through the nonampullated end of the horizontal canal. This kind of vertigo recovers spontaneously more rapidly and suddenly.

  6. 77 FR 26699 - Safety Zone; Coast Guard Exercise, Hood Canal, WA

    Science.gov (United States)

    2012-05-07

    ... the exercise to allow for a comment period. The safety zone created is short in duration, and vessels... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Coast Guard Exercise, Hood Canal, WA AGENCY... safety zone around vessels involved in a Coast Guard Ready for Operations exercise in Hood Canal, WA...

  7. 33 CFR 207.20 - Cape Cod Canal, Mass.; use, administration, and navigation.

    Science.gov (United States)

    2010-07-01

    ... the Canal Electric Terminal. (iv) Fourth—To merchant vessels, towboats, commercial fishing vessels.... Fishing boats, yachts, cabin cruisers and other craft utilizing the East Boat Basin on the south side of... and craft of every description through the canal and the operation and maintenance of the waterway...

  8. Classification, mechanism and surgical treatments for spinal canal cysts

    Institute of Scientific and Technical Information of China (English)

    Jianjun Sun

    2016-01-01

    A variety of cystic lesions may develop in spinal canal. These cysts can be divided into intramedullary, intradural, extradural, cervical, thoracic, lumbar, and sacral cysts according to anatomical presentation, as well as arachnoid, meningeal, perineural, juxtafacet, discal, neurenteric cysts, and cyst-like lesions according to different etiologies. Mechanisms of initiation and growth vary for different cysts, such as congenital, trauma, bleeding, inflammatory, instability, hydrostatic pressure, osmosis of water, secretion of cyst wall, and one-way-valve effect, etc. Up to now, many treatment methods are available for these different spinal canal cysts. One operation method can be applied in cysts with different types. On the other hand, several operation methods may be utilized in one type of cyst according to the difference of location or style. However, same principle should be obeyed in surgical treatment despite of difference among spinal canal cysts, given open surgery is melely for symptomatic cyst. The surgical approach should be tailored to the individual patient.

  9. Mejoras en el canal de Panamá

    Directory of Open Access Journals (Sweden)

    Brandl, Charles McG.

    1963-07-01

    Full Text Available The Panama Canal, together with the Suez Canal, is an engineering accomplishment which is now regarded as a master work marking the initiation of modern civil engineering. Other projects, also of great magnitude, do not seem to maintain the reputation of the above two, because they cannot continue to serve their function with sustained usefulness in the new circumstances of today. The Panama Canal, with its limited dock capacity, and the narrow, so called Serpent, canal, has had to cope with a continuously increasing volume of shipping traffic; a natural consequence of commercial evolution. In order to keep up with these increasing demands, it has been necessary to carry out an almost uninterrupted series of modifications and improvements, affecting both the method of operation and organisation, and the actual nature of the canal. Thanks to these alterations the Panama Canal has continued to maintain, at least nominally, an adequate standard of functional efficiency. At present the canal is being widened over certain sections to enable the easy passage of ships of great displacement. The work is being done very rapidly, and in order to gain time, it has been distributed to various contractors simultaneously.El canal a través del ismo de Panamá es una obra de ingeniería civil que, junto con el de Suez, empiezan ya a clasificarse como obras maestras que señalan el primer jalón del desarrollo de la ingeniería moderna. Otras obras, también importantes, no conservan, sin embargo, la misma reputación que aquéllas, por no seguir un paralelismo con las exigencias en cada época. El canal de Panamá, con sus exclusas, y angosto paso llamado de la. Culebra, ha tenido que afrontar un tráfico creciente de navíos que siguen la evolución del tiempo. Para conseguir este paralelismo, tanto el material de explotación como la organización, dragados y mejoras, han tenido que conocer una sucesión ininterrumpida de modificaciones que han permitido

  10. Single C-shaped canal in mandibular first molar: A case report

    Directory of Open Access Journals (Sweden)

    Srinidhi Surya Raghavendra

    2015-01-01

    Full Text Available The variability of root canal system morphology presents a continuous challenge to endodontic diagnosis and therapeutics. There have been reports of teeth with multiple roots and canals as also those with lesser number of root and root canals. Variations of root canal systems need not always be in the form of extra canals. Clinicians should be aware that there is a possibility of existence of fewer numbers of roots and root canals than normal, which presents varied canal anatomy and poses a challenge to the clinician′s expertise. This case report deals with the management of an unusual case of C-shaped canal in mandibular molar with two buccally fused roots. Cone-beam computed tomography (CBCT was employed to confirm the extension of the unusual anatomy. The Self Adjusting File (SAF system was used to ensure complete cleaning of the canal system. One-year follow-up of the case showed good healing. The clinician should expect to encounter unusual features when performing endodontic treatment. Use of diagnostic aids like CBCT, improved magnification with dental operating microscope, and the use of novel file systems like SAF ensure success.

  11. The microsonics concept: maxillary first molar with five root canals – case report

    Directory of Open Access Journals (Sweden)

    Rodrigo Sanches Cunha

    2011-04-01

    Full Text Available Introduction: The complex anatomy of the root canal system is a continuous challenge for endodontists. Permanent maxillary first molars may present several morphological variations, both in the number and location of roots and canals. Therefore, the success of the endodontic treatment depends on an accurate knowledge of root canal anatomy. Objective and case report: This study describes the endodontic treatment of a permanent maxillary first molar diagnosed with irreversible pulpitis. The technology employed to evaluate the case, namely dental operating microscope associated with ultrasonic tips, was essential to delineate the anatomic characteristics of the tooth to be treated, revealing the presence of five root canals: two mesiobuccal, two distobuccal, and one palatal canal. Conclusion: The knowledge of the tooth anatomy, as well as its possible anatomic variations, combined with the use of current technologies, such as dental operating microscope, ultrasonic tips, and computed tomography, help to enhance the endodontic treatment success.

  12. 33 CFR 117.1051 - Lake Washington Ship Canal.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Lake Washington Ship Canal. 117.1051 Section 117.1051 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Washington § 117.1051 Lake Washington...

  13. Canals - CANALS_HISTORIC_STRUCTURES_IN: Historic Canal Structures in Indiana (Bernardin-Lochmueller & Associates, Point Shapefile)

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — Data depicts the locations of historic structures associated with the Wabash-Erie, Central, and Whitewater Canals constructed in Indiana in from 1830-1870. Canal...

  14. Fluidmechanics of semicircular canals revisited

    Science.gov (United States)

    Obrist, Dominik

    2008-05-01

    In this work we find the exact solution for the flow field in a semicircular canal which is the main sensor for angular motion in the human body. When the head is rotated the inertia of the fluid in the semicircular canal leads to a deflection of sensory hair cells which are part of a gelatinous structure called cupula. A modal expansion of the governing equation shows that the semicircular organ can be understood as a dynamic system governed by duct modes and a single cupular mode. We use this result to derive an explicit expression for the displacement of the cupula as a function of the angular motion of the head. This result shows in a mathematically and physically clean way that the semicircular canal is a transducer for angular velocity.

  15. Water losses from irrigation canals evaluation: comparison among different methodologies

    Science.gov (United States)

    Clemente, Paolo; De Luca, Domenico Antonio; Antonella Dino, Giovanna; Lasagna, Manuela

    2013-04-01

    , especially for low canal discharge, because of the high instrumental error. A more rigorous method, based on the quantification of artificial tracers mass losses through exfiltration, was tested. This methodology is based on QUEST method (Rieckermann J. & Guier W., 2002; De Luca et alii, 2012). The used tracers were sodium chloride (NaCl), uranine and rhodamine WT. Uranine and rhodamine were detected by means of a fluorometer and NaCl thanks to a conductivimeter. In order to reduce the error of the NaCl detection, a multistage sampling in different parts of the cross section was applied, guaranteeing the contemporary water picking up. The results of these last tests were more accurate and in accordance with the aim of the research. References De Luca D. A., Comina C., Destefanis E., Marzano F., Carbotta G., Dino G., Passarella I., Masciocco L., Sambuelli L., Perotti L., Lasagna M., Clemente P., Bonetto S. (2012). Definizione di linee guida per la valutazione delle perdite dei canali irrigui. Convenzione scientifica tra Dipartimento di Scienze della Terra e Regione Piemonte - Direzione Agricoltura. Final Report. Rieckermann J., Gujer W. (2002) - Quantifying Exfiltration from Leaky Sewers with Artificial Tracers - Proceedings of the International Conference on "Sewer Operation and Maintenance. 2002", Bradford, UK.

  16. INSTRUMENTATION OF CURVED CANALS: A REVIEW

    Directory of Open Access Journals (Sweden)

    Senthil Kumar

    2013-02-01

    Full Text Available INTRODUCTION: Nature seldom draws a straight line. Nowhere is thi s more apparent than in the anatomy of teeth roots and root canal systems o f human teeth. Even teeth with straight roots can harbor severely curved canals. Canal shapi ng is a critical aspect of endodontic treatment because it influences the outcome of the subsequent phases of canal irrigation and filling and the success of the treatment itself. In fact, curved canals are the most common endodontic complexity 1 . The need for some manner of root canal preparation pri or to root canal filling has long been recognized as an essential step in endodontic t reatment. Concepts concerning the role and purpose of this canal preparation, however, have differ ed remarkably at different times in the development of endodontics and in the hands of diffe rent practitioners 2

  17. Computed tomography of the thoracic canal

    International Nuclear Information System (INIS)

    Under the adequate CT condition, thoracic canal was studied in twelve normal cases, nine cases of cervical myelopathy with developmental cervical canal stenosis and four cases of thoracic myelopathy with ossification of thoracic yellow ligament. The results were as follows. 1) The adequate condition for delineation of thoracic canal seemed to be nearly 400 EMI units in window width and 150 in level. Scanning angle was permitted within about 100. Bony thoracic canal was well scanned at the center of vertebral body. 2) The configulation of the normal thoracic canal was oval at Th1, Th2 levels and round at Th3-Th10 and large oval at Th11, Th12. The sagittal diameter was almost fixed at each level and the transverse diameter was large at upper and lower levels and small at middle levels. 3) Thoracic canal was narrowed in the cases of cervical myelopathy with developmental cervical canal stenosis especially in sagittal diameter, but not narrowed in transverse diameter. Three of four cases who had myelopathy with ossification of thoracic yellow ligament had narrow canals. 4) There was a good relation between sagittal diameter of cervical canal and thoracic canal. 5) There was a good relation between sagittal diameter of thoracic canal measured by conventional radiographs (Hattori's method) and CT scans. The author thinks that Hattori's method is useful to diagnose the thoracic canal stenosis. (author)

  18. Contemporary root canal filling strategies

    NARCIS (Netherlands)

    A.T. Moinzadeh

    2016-01-01

    Currently, clinicians can choose from a wide range of root canal filling materials and techniques, some of which have been evaluated in this thesis. Methacrylate resin-based sealers suffer from polymerization shrinkage stresses. This limitation may partly be overcome by a two-step cementation proced

  19. Canal Water Scarcity Hits Farmers

    Institute of Scientific and Technical Information of China (English)

    张忠潮

    2007-01-01

    Acute shortage of canal water for irrigation in this district has caused resentment among the farmers.The water is being released in the various channels for just one week in a month,which is not enough to meet the irrigation needs of the farmers who are preparing their fields for paddy

  20. Maxillary first molar with seven root canals diagnosed with cone-beam computed tomography scanning

    Directory of Open Access Journals (Sweden)

    Anil Munavalli

    2015-01-01

    Full Text Available Nonsurgical endodontic therapy of a right maxillary first molar with three roots and seven root canals. This unusual morphology was diagnosed using a dental operating microscope (DOM and confirmed with the help of cone-beam computed tomography (CBCT images. CBCT axial images showed that both the palatal and distobuccal root have a Vertucci type II canal pattern, whereas the mesiobuccal root showed a Sert and Bayirli type XVIII canal configuration. The use of a DOM and CBCT imaging in endodontically challenging cases can facilitate a better understanding of the complex root canal anatomy, which ultimately enables the clinician to explore the root canal system and clean, shape, and obturate it more efficiently.

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

    Science.gov (United States)

    Brykala, Dariusz; Badziai, Vitali

    2014-05-01

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

  2. 显微超声技术应用于钙化根管治疗的相关研究%Correlation research on dental operating microscope and ultrasonic instruments in the treatment of calcified root canals

    Institute of Scientific and Technical Information of China (English)

    韩宁; 孙克勤

    2015-01-01

    显微超声技术是一种可以有效提高钙化根管治疗成功率的新方法,显微镜的放大和照明系统将传统牙髓治疗从盲目变为可视,为根管治疗尤其是钙化根管的彻底治疗提供了重要保证,因此在口腔临床中得到了广泛应用。本文将对显微超声技术应用于钙化根管治疗的相关研究进行综述。%Ultrasonic microscope technique is a new method that can effectively increase the success rate of calcified canal treatment. With its magnification and lighting systems, microscopic ultrasound technology enables traditional endodontic treatment to become visible from blind. This technology ensures effective root canal treatment and thorough treatment of calcified root canal. Thus, this technique has been widely used in oral clinics. This paper aims to review the correlation research on dental operating microscope and ultrasonic instruments in the treatment of calcified root canals.

  3. Mandibular Second Premolar with Four Canals

    Directory of Open Access Journals (Sweden)

    Javad Ghiasi

    2015-09-01

    Full Text Available A mandibular second premolar with four canals is an interesting example of anatomic variations. This report describes a case of a mandibular second premolar with three roots and four canals (one mesiobuccal, two distobuccal and one lingual. The canals were prepared using K-files and irrigated with NaOCl (5.25% and normal saline as the final irrigant. The canals were filled laterally with gutta percha and AH26 sealer (De Trey, Dentsply, Switzerland. This case shows a rare anatomic configuration and points out the importance of looking for additional canals.

  4. CBCT-Aided Microscopic and Ultrasonic Treatment for Upper or Middle Thirds Calcified Root Canals

    Science.gov (United States)

    Yang, Ying-Ming; Guo, Bin; Guo, Li-Yang; Yang, Yan; Hong, Xiao; Pan, Hong-Ying

    2016-01-01

    Root canal calcification is considered a great challenge during root canal treatment. Although the application of ultrasonic instruments and dental operating microscope (DOM) has advantages, dealing with calcified root canals still suffers a great risk of failure because of limited information about the location, length, and direction of obliteration on periapical radiographs. In this work, a cone-beam computed tomography- (CBCT-) aided method aimed at solving complicated calcified root canals in which conventional approaches could not work was proposed. Thirteen teeth with sixteen calcified canals (12 calcified in the upper third, 4 calcified in the middle third), which cannot be negotiated with conventional methods, were treated with the aid of CBCT. The location of calcification and depth of instrumentation and operating direction were calculated and assessed in three dimensions with ultrasonic instruments under DOM. In all thirteen teeth, canals with upper and middle thirds calcification were treated successfully. Finally, a guideline was proposed to help achieve consistent apical patency in calcified canals. PMID:27525269

  5. Retention of Root Canal Posts

    DEFF Research Database (Denmark)

    Sahafi, A; Benetti, Ana Raquel; Flury, S;

    2015-01-01

    The aim of this study was to investigate the effect of the cement film thickness of a zinc phosphate or a resin cement on retention of untreated and pretreated root canal posts. Prefabricated zirconia posts (CosmoPost: 1.4 mm) and two types of luting cements (a zinc phosphate cement [DeTrey Zinc...... received tribochemical silicate coating according to the manufacturer's instructions. Posts were then luted in the prepared root canals (n=30 per group). Following water storage at 37°C for seven days, retention of the posts was determined by the pull-out method. Irrespective of the luting cement......, pretreatment with tribochemical silicate coating significantly increased retention of the posts. Increased cement film thickness resulted in decreased retention of untreated posts and of pretreated posts luted with zinc phosphate cement. Increased cement film thickness had no influence on retention...

  6. Scalloping at the lumbosacral canal

    International Nuclear Information System (INIS)

    Scalloping is an indentation of the dorsal side of the vertebral body (anterior wall of the lumbosacral or sacral canal) which typically involves several adjacent lumbal vertebral body segments and the anterior wall of the canalis sacralis. Occurrence without underlying disease is rare; it occurs most frequently with chondrodystrophy, neurofibromatosis, Morquio's syndrome, Hurler's syndrome, acromegaly, Ehlers-Danlos syndrome, Marfan's syndrome, cysts, tumors and in peridural lipomas. (orig.)

  7. Scalloping at the lumbosacral canal

    Energy Technology Data Exchange (ETDEWEB)

    Reinhardt, R.

    1987-07-01

    Scalloping is an indentation of the dorsal side of the vertebral body (anterior wall of the lumbosacral or sacral canal) which typically involves several adjacent lumbal vertebral body segments and the anterior wall of the canalis sacralis. Occurrence without underlying disease is rare; it occurs most frequently with chondrodystrophy, neurofibromatosis, Morquio's syndrome, Hurler's syndrome, acromegaly, Ehlers-Danlos syndrome, Marfan's syndrome, cysts, tumors and in peridural lipomas.

  8. Contemporary root canal filling strategies

    OpenAIRE

    Moinzadeh, A.T.

    2016-01-01

    Currently, clinicians can choose from a wide range of root canal filling materials and techniques, some of which have been evaluated in this thesis. Methacrylate resin-based sealers suffer from polymerization shrinkage stresses. This limitation may partly be overcome by a two-step cementation procedure. This alternative placement technique results in an increase and homogenization of the adhesion of the material to intraradicular dentin. Subsequent research should aim at developing sealers wi...

  9. 根管阻塞的临床研究%The clinic research of canal blockage

    Institute of Scientific and Technical Information of China (English)

    杨焰; 陈美玲; 金铁虎; 马净植

    2012-01-01

    Objective: To summarize the main etiology of canal blockage and the main contributing factors of successful negotiation through treating and analyzing the clinical cases with blocked root canals. Method: 89 patients with 107 blocked root canals were involved. All the canals were negotiated by using ultrasonic technique and small size hand files under dental operating microscope. The root canal blockage and negotiation results were recorded. Result: The common etiology of canal blockage included root canal treatment history . Calcifications and other factors. The blocked canals were more often occurred in the molars than in anterior teeth and premolars.and the success rate of blocked canals being managed was lower in the molars. The success rate of each category of the blocked canals was: 85 % for canals filled with gutta-percha. 52.8 % for canals subjected to resinifying therapy. 69.7 % for calcified root canals, and 55.6 % for blocked canals caused by other factors. Canals showed on radiograph clearly had a success rate of 75.3 % . Whereas those that were not visible on the X-ray film had a significantly lower success rate of 47.6 % (P <0.05). The success rate of blocked canals at the coronal third is higher than that at the apical third (P <0.05). Conclusion: Resinifying therapy and calcification are the main factors resulting in blocked canals. Blocked canals caused by resinifying therapy were managed with the lower success rate. The blockage locations in canals and the teeth positions influence the success rate of blocked canal therapy.%目的:总结根管阻塞的主要原因及影响阻塞根管疏通的主要因素.方法:收集病例89例,共107个根管阻塞,在显微镜下使用超声器械和小号手用器械进行根管疏通.记录根管阻塞的情况和效果.结果:根管阻塞的原因主要有根管治疗史及钙化等.磨牙的根管较前牙及前磨牙易发生阻塞,且疏通成功率较低.因牙胶充填、塑化、钙化和其他原因

  10. Nested Canalizing Functions and Their Networks

    CERN Document Server

    Kadelka, Claus; Adeyeye, John O; Laubenbacher, Reinhard

    2014-01-01

    The concept of a nested canalizing Boolean function has been studied over the last decade in the context of understanding the regulatory logic of molecular interaction networks, such as gene regulatory networks. Such networks are predominantly governed by nested canalizing functions. Derrida values are frequently used to analyze the robustness of a Boolean network to perturbations. This paper introduces closed formulas for the calculation of Derrida values of networks governed by Boolean nested canalizing functions, which previously required extensive simulations. Recently, the concept of nested canalizing functions has been generalized to include multistate functions, and a recursive formula has been derived for their number, as a function of the number of variables. This paper contains a detailed analysis of the class of nested canalizing functions over an arbitrary finite field. In addition, the concept of nested canalization is further generalized and closed formulas for the number of such generalized fun...

  11. Stability of guest molecules in urea canal complexes by canal polymerization

    International Nuclear Information System (INIS)

    It was found that various organic materials are attracted into urea canal by hexanediol diacrylate (HDDA) and long chain compounds. This means that materials which does not form complex by itself are induced in canal by HDDA and long chain compounds. To include with stability perfumes, insecticides, attractants and repellents in urea canal, leaf alcohol was used as a model compound for guest molecules in the canal. The leaf alcohol from the canal released gradually over many days and the release was inhibited for 15 days by long chain compounds and for 30 days by polymerized HDDA after irradiation. After releasing, the leaf alcohol in the canal remained 25 % stable for long chain compounds and 40 % for polymerized HDDA. The dose required for stabilization of leaf alcohol in the urea canal by canal polymerization of HDDA was 30 kGy. (author)

  12. Stability of guest molecules in urea canal complexes by canal polymerization

    Energy Technology Data Exchange (ETDEWEB)

    Yoshii, Fumio; Makuuchi, Keizo [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    1995-03-01

    It was found that various organic materials are attracted into urea canal by hexanediol diacrylate (HDDA) and long chain compounds. This means that materials which does not form complex by itself are induced in canal by HDDA and long chain compounds. To include with stability perfumes, insecticides, attractants and repellents in urea canal, leaf alcohol was used as a model compound for guest molecules in the canal. The leaf alcohol from the canal released gradually over many days and the release was inhibited for 15 days by long chain compounds and for 30 days by polymerized HDDA after irradiation. After releasing, the leaf alcohol in the canal remained 25 % stable for long chain compounds and 40 % for polymerized HDDA. The dose required for stabilization of leaf alcohol in the urea canal by canal polymerization of HDDA was 30 kGy. (author).

  13. Canals, DMADCanals-Irrigation canals in Millard Co., Published in 2007, Millard County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Canals dataset, was produced all or in part from Other information as of 2007. It is described as 'DMADCanals-Irrigation canals in Millard Co.'. Data by this...

  14. Complicated canal morphology of mandibular first premolar

    Science.gov (United States)

    Pallavi, Vyapaka; Kumar, Janga Ravi; Mandava, Ramesh Babu; Rao, Subramanian Hari

    2015-01-01

    The aim of this article was to report an unusual anatomic variation of mandibular first premolar, with one root and three distinct canals, which leave pulp chamber and merge short of apex to exit as two separate apical foramina. The incidence of three canals existing as two apical foramina has only been documented in the literature by a few case reports. To achieve successful endodontic treatment, the clinician has to identify the different canal configurations and treat them properly. PMID:26538977

  15. The number and probability of canalizing functions

    OpenAIRE

    Just, Winfried; Shmulevich, Ilya; Konvalina, John

    2003-01-01

    Canalizing functions have important applications in physics and biology. For example, they represent a mechanism capable of stabilizing chaotic behavior in Boolean network models of discrete dynamical systems. When comparing the class of canalizing functions to other classes of functions with respect to their evolutionary plausibility as emergent control rules in genetic regulatory systems, it is informative to know the number of canalizing functions with a given number of input variables. Th...

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

    DEFF Research Database (Denmark)

    Jenstrup, M T; Jæger, P; Lund, J;

    2012-01-01

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

  17. MANAGEMENT OF LUMBAR SPINAL CANAL STENOSIS

    Directory of Open Access Journals (Sweden)

    Mukhergee G. S

    2016-06-01

    degenerative. This process is most commonly localised to the facet joints and ligamentum flavum, with the resultant arthritic changes in the joints visible on radiographic studies. Frequently, these abnormalities are symmetrical and bilateral. The L4-L5 level is the most commonly involved, followed by L5-S1 and L3-L4 disc herniation and spondylolisthesis may exacerbate the narrowing further. 1. METHODS This study was taken up to evaluate the management of lumbar spinal canal stenosis cases. The study was conducted from May 2012 to October 2014: A total of 86 patients of 55-70 age groups with degenerative LCS were followed prospectively from May 2012 to October 2014. All the treatment methods were explained to patients and treatment method was determined by patient’s choice. The sample is divided into two groups 42 surgical and 44 conservative based on patient’s preference. MEASUREMENT OF OUTCOME Outcomes were measures of bodily pain and physical function on the medical outcomes study 36-item short-Form General Health Study (SF-36 22-25 and on the modified Oswestry Disability Index 26 measured at 6 weeks, 3 months, 6 months, and 1 year and 18 months. SF-36 scores range from 0 to 100 with higher scores indicating less severe symptoms. The Oswestry Disability Index ranges from 0 to 100, with lower scores indicating less severe symptoms. STUDY INTERVENTION The protocol surgery was standard posterior decompressive laminectomy operated by three surgeons. The type of nonsurgical care included physical therapy (68% of patients, epidural injections (56%, the use of anti-inflammatory drugs (55% and use of opioid analgesics (27%. Informed consent was taken from every patient after explaining the particulars of study interventions. In this study, 82% patients (n=70 were in age group 50-59 years with an average age of 50.2 years with a total sample size of 86 patients followed by 60-69 years age group. Both the surgical and conservative groups had similar sex distribution. Initially

  18. Narrow, duplicated internal auditory canal

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, T. [Servico de Neurorradiologia, Hospital Garcia de Orta, Avenida Torrado da Silva, 2801-951, Almada (Portugal); Shayestehfar, B. [Department of Radiology, UCLA Oliveview School of Medicine, Los Angeles, California (United States); Lufkin, R. [Department of Radiology, UCLA School of Medicine, Los Angeles, California (United States)

    2003-05-01

    A narrow internal auditory canal (IAC) constitutes a relative contraindication to cochlear implantation because it is associated with aplasia or hypoplasia of the vestibulocochlear nerve or its cochlear branch. We report an unusual case of a narrow, duplicated IAC, divided by a bony septum into a superior relatively large portion and an inferior stenotic portion, in which we could identify only the facial nerve. This case adds support to the association between a narrow IAC and aplasia or hypoplasia of the vestibulocochlear nerve. The normal facial nerve argues against the hypothesis that the narrow IAC is the result of a primary bony defect which inhibits the growth of the vestibulocochlear nerve. (orig.)

  19. Root Canal Treatment of a Maxillary Second Premolar with Two Palatal Root Canals: A Case Report.

    Science.gov (United States)

    Golmohammadi, Maryam; Jafarzadeh, Hamid

    2016-01-01

    Accurate diagnosis of the root canal morphology and anatomy is essential for thorough shaping and cleaning of the entire root canal system and consequent successful treatment. This report describes a case of maxillary second premolar with two roots and three root canals (two mesial and distal palatal canals). The case report underlines the importance of complete knowledge about root canal morphology and possible variations, coupled with clinical and radiographic examination in order to increase the ability of clinicians to treat difficult cases. PMID:27471538

  20. [Upper lateral incisor with 2 canals].

    Science.gov (United States)

    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. PMID:1659854

  1. [Upper lateral incisor with 2 canals].

    Science.gov (United States)

    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.

  2. Blending Canal Surfaces Based on PH Curves

    Institute of Scientific and Technical Information of China (English)

    Chen-Dong Xu; Fa-Lai Chen

    2005-01-01

    In this paper, a new method for blending two canal surfaces is proposed. The blending surface is itself a generalized canal surface, the spine curve of which is a PH (Pythagorean-Hodograph) curve. The blending surface possesses an attractive property - its representation is rational. The method is extensible to blend general surfaces as long as the blending boundaries are well-defined.

  3. Type III apical transportation of root canal

    Directory of Open Access Journals (Sweden)

    Shiv P Mantri

    2012-01-01

    Full Text Available Procedural accidents leading to complications such as canal transportation have been ascribed to inapt cleaning and shaping concepts. Canal transportation is an undesirable deviation from the natural canal path. Herewith a case of apical transportation of root canal resulting in endodontic retreatment failure and its management is presented. A healthy 21-year-old young male presented discomfort and swelling associated with painful endodontically retreated maxillary incisor. Radiograph revealed periradicular radiolucency involving underfilled 11 and overfilled 12. Insufficiently obturated 11 exhibited apical transportation of canal. This type III transportation was treated by periradicular surgery and repair using white mineral trioxide aggregate (MTA. Comfortable asymptomatic patient presented uneventful healing at third and fourth month recall visits. A decrease in the size of radiolucency in radiograph supported the clinical finding. In the present case, MTA is useful in repairing the transportation defect. The result of these procedures is predictable and successful.

  4. Clinical management of infected root canal dentin.

    Science.gov (United States)

    Love, R M

    1996-08-01

    Several hundred different species of bacteria are present in the human intraoral environment. Bacterial penetration of root canal dentin occurs when bacteria invade the root canal system. These bacteria may constitute a reservoir from which root canal reinfection may occur during or after endodontic treatment. The learning objective of this article is to review endodontic microbiology, update readers on the role of bacteria in pulp and periapical disease, and discuss the principles of management of infected root canal dentin. Complete debridement, removal of microorganisms and affected dentin, and chemomechanical cleansing of the root canal are suggested as being the cornerstones of successful endodontic therapy, followed by intracanal medication to remove residual bacteria, when required.

  5. MRI Findings in Spinal Canal Stenosis

    Directory of Open Access Journals (Sweden)

    Maryam Barzin

    2010-05-01

    Full Text Available Spinal canal stenosis results from progressive narrowing of the central spinal canal and the lateral recesses. Primary (congenital lumbar spinal stenosis is associated with achondroplastic dwarfism. The spinal canal may become narrowed by bulging or protrusion of the intervertebral disc annulus, herniation of the nucleus pulposus posteriorly, thickening of the posterior longitudinal ligament, hypertrophy of the facet joints, hypertrophy of the ligamentum flavum, epidural fat deposition, spondylosis of the intervertebral disc margins and uncovertebral joint hypertrophy in the neck. The central canal and the neurorecess may be compromised by tumor infiltration, such as metastatic disease, or by infectious spondylitis."nAP diameter of the normal adult cervical canal has a mean value of 17-18 mm at vertebral levels C3-5. The lower cervical canal measures 12-14 mm. Cervical stenosis is associated with an AP diameter of less than 10 mm. The thoracic spinal canal varies from 12 to 14 mm in diameter in the adult. The diameter of the normal lumbar spinal canal varies from 15 to 27 mm. Lumbar stenosis results from a spinal canal diameter of less than 12 mm in some patients; a diameter of 10 mm is definitely stenotic."nSpinal MRI is the most suitable technique for the diagnosis of spinal stenosis. The examination should be performed using thin sections (3 mm and high resolution, including the axial and sagittal planes using T1-weighted, proton-density, and T2-weighted techniques. The bony and osteophytic components are seen best using a T2-weighted gradient-echo technique."nOn MRI, findings of spinal stenosis have a variable presentation depending on the specific disease. The goal of spinal imaging is to localize the site and level of disease and to help differentiate between conditions in which patients require surgery or conservative treatment."nIn this presentation, different kinds of spinal canal stenosis and their MRI findings would be discussed.

  6. How to bond to root canal dentin

    Science.gov (United States)

    Nica, Luminita; Todea, Carmen; Furtos, Gabriel; Baldea, Bogdan

    2014-01-01

    Bonding to root canal dentin may be difficult due to various factors: the structural characteristic of the root canal dentin, which is different from that of the coronal dentin; the presence of the organic tissue of the dental pulp inside the root canal, which has to be removed during the cleaning-shaping of the root canal system; the smear-layer resulted after mechanical instrumentation, which may interfere with the adhesion of the filling materials; the type of the irrigants used in the cleaning protocol; the type of the sealer and core material used in the obturation of the endodontic space; the type of the materials used for the restoration of the endodontically treated teeth. The influence of the cleaning protocol, of the root canal filling material, of the type of the adhesive system used in the restoration of the treated teeth and of the region of the root canal, on the adhesion of several filling and restorative materials to root canal dentin was evaluated in the push-out bond strength test on 1-mm thick slices of endodontically treated human teeth. The results showed that all these factors have a statistically significant influence on the push-out bond strength. Formation of resin tags between radicular dentin and the investigated materials was observed in some of the samples at SEM analysis.

  7. 21 CFR 872.3810 - Root canal post.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Root canal post. 872.3810 Section 872.3810 Food... DEVICES DENTAL DEVICES Prosthetic Devices § 872.3810 Root canal post. (a) Identification. A root canal... of the platinum group intended to be cemented into the root canal of a tooth to stabilize and...

  8. [Treatment of a fractured endodontical instrument in the root canal].

    Science.gov (United States)

    Schipper, M; Peters, L B

    2015-12-01

    A 53-year-old woman with continuing pain coming from a lower first molar was diagnosed with apical periodontitis, with a retained fractured instrument in the root canal. There are a variety of treatment options for dealing with a corpus alienum in a root canal. In this case it was decided to treat the tooth endodontically, and leave the fractured instrument fragment in situ. The selection of this treatment option was made on the basis of knowledge of the original diagnosis and the success rates of the various treatment options as described in the relevant literature, weighed against the possible risks and their effects on the prognosis. This suggested that the use of a dental operating microscope has a positive impact on the success rates of endodontic treatment The prognosis for endodontic treatment when a fractured instrument fragment is left within the root canal, as in this case, is not significantly reduced. The presence of preoperative periapical pathology, however, is a more clinically significant prognostic indicator. PMID:26665200

  9. Comparison of Bacterial Leakage between 3 Different Root Canal Obturation Techniques in Oval Shaped Canals

    OpenAIRE

    Eshagh-ali Saberi; Shahram Shahraki; Sediqe Ebrahimipour; Anousheh Rashed Mohassel; Narjes Akbari; Majid Rezaei

    2014-01-01

    Introduction: The purpose of this study was to evaluate the sealing ability of 3 obturation techniques in oval-shaped canals by bacterial leakage assessment. Methods: Sixty mandibular incisors with oval canals were selected after providing buccolingual and mesiodistal radiographs. The teeth were sectioned at a 10 mm distance from the apex. After instrumentation, the teeth were divided into 3 groups and the canals in the three groups were obturated with lateral condensation (G1), warm vertical...

  10. Integrated Watershed Pollution Control at Wujingang Canal, China

    Science.gov (United States)

    Zheng, Z.; Yang, X.; Luo, X.

    2012-04-01

    With a drainage area of 400 square kilometers, Wujingang Canal is located at the economically developed Yangtz Delta of eastern China. As a major tributary, the canal contributes a significant amount of pollutant load to the Lake Tai. Over the past many years, water quality of the canal and its tributaries could not meet the lowest Category V of Chinese surface water quality standard, indicating that its water is not suitable for the purposes of irrigation or scenic views. Major pollution sources in the watershed include industries, residential households, agriculture, fishery, and animal feedlot operations. A comprehensive plan with a budget of 2 billion RMB for the Wujingang watershed pollution control was developed in 2008 and has been implemented progressively ever since. Major components of the plan include: (1) advanced treatment of wastewater from industries and municipal sewage plants for further removal of nitrogen and phosphorous; (2) industrial wastewater reuse; (3) contiguous treatment of sewage from rural residential households with cost-effective technologies such as tower ecofilter system; (4) recycling of rural wastes to generate high-value added products using technologies such as multi-phase anaerobic co-digestion; and (5) making full use of the local landscape and configuring physical, chemical, and biological pollutant treatment structures to build the "clean river network" for treatment of mildly polluted agricultural discharge and surface runoff. Through the implementation of the above measures, water quality of the Wujingang Canal and its tributaries is expected to improve to meet Category IV of Chinese surface water quality standard by 2012, and Category III standard by 2020. Keywords watershed pollution control, non-point source pollution, rural sewage, rural waste, Lake Tai

  11. Centering Ability and Influence of Experience When Using WaveOne Single-File Technique in Simulated Canals

    Directory of Open Access Journals (Sweden)

    Mathieu Goldberg

    2012-01-01

    Full Text Available Introduction. WaveOne is a single endodontic instrument that reciprocates with a dedicated motor to shape root canal systems. The present study assessed the centering ability of this simplified protocol along with the effect of experience in simulated plastic canals. Methods. One experienced operator shaped two groups of simulated canals. Groups 1 and 3 each comprised 30 blinded L-shaped canals or S-shaped canals, respectively. Photographs were taken before and after shaping and digitally assessed centering after superimposition of the pictures. Time of shaping, number of passes, canal aberrations, and instrument degradation were recorded. In group 2 shaping was done on 30 blinded L-shaped canals by 30 different students with no prior experience with WaveOne. Results. All three groups yielded satisfactory, reproducible shaping. Centering ratios were low and homogeneous in all groups, with no significant differences between the experienced operator and the students. Apical transportation values were very low (≤0.138 mm with no instances of blockage or separation. The average shaping time was short (43 to 101,6 sec. Conclusions. Within the limits of the study, the WaveOne instrument had excellent centering ability with a low risk of fracture or blockage and a short shaping time, regardless of the operator’s level of experience.

  12. MANAGEMENT OF LUMBAR SPINAL CANAL STENOSIS

    OpenAIRE

    Mukhergee G. S; Kiran Kumar L; Manikumar C. J

    2016-01-01

    BACKGROUND Spinal stenosis is one of the most common conditions in the elderly. It is defined as a narrowing of the spinal canal. The term stenosis is derived from the Greek word for narrow, which is “Stenos”. The first description of this condition is attributed to Antoine portal in 1803. Verbiest is credited with coining the term spinal stenosis and the associated narrowing of the spinal canal as its potential cause. [1-10] Kirkaldy–Willis subsequently described the de...

  13. Pain associated with root canal treatment

    OpenAIRE

    Segura-Egea, Juan José; Cisneros Cabello, Rafael; Llamas Carreras, José María; Velasco Ortega, Eugenio

    2009-01-01

    Our purpose was to determine the pain experienced by patients during root canal treatment and to correlate with age and gender, pulpal diagnosis, previous periapical status, dental characteristics and length of treatment. One hundred and seventy-six patients (68 men and 108 women), with ages ranged from 6 to 83 years, were randomly recruited. Patients completed a 10-cm visual analogue scale (VAS) that ranked the level of pain experienced during root canal treatment. The mean pain level during...

  14. Two root canals in maxillary central incisor

    Directory of Open Access Journals (Sweden)

    Fábio de Almeida Gomes

    2011-07-01

    Full Text Available Introduction and objective: The success of endodontic treatment requires the knowledge of tooth morphology and its variations. Case report: This clinical article reports an unusual root canal configuration that was detected in a maxillary central incisor with two root canals, demonstrated by radiographic and computerized tomography exams. Conclusion: Knowledge of endodontic anatomy as well as the obtainment of both preoperative radiographs and tomography is important to detect abnormal tooth morphology.

  15. Mechanics of the Panama Canal slides

    Science.gov (United States)

    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.

  16. Optimizing the semicircular canal: could we balance any better?

    CERN Document Server

    Squires, T M

    2004-01-01

    The fluid-filled semicircular canals (SCCs) of the vestibular system are used by all vertebrates to sense angular rotation. Despite masses spanning seven decades, all mammalian SCCs are nearly the same size. We propose that the SCC represents a sensory organ that evolution has `optimally designed'. Four geometric parameters are used to characterize the SCC, and `building materials' of given physical properties are assumed. Identifying physical and physiological constraints on SCC operation, we find that the most sensitive SCC has dimensions consistent with available data.

  17. Posterior semicircular canal dehiscence: a morphologic cause of vertigo similar to superior semicircular canal dehiscence

    Energy Technology Data Exchange (ETDEWEB)

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

    2003-06-01

    Heading Abstract.The aim of this study was to assess imaging findings of posterior semicircular dehiscence on computed tomography and to evaluate incidence of posterior and superior semicircular canal dehiscence in patients presenting with vertigo, sensorineuronal hearing loss or in a control group without symptoms related to the inner ear. Computed tomography was performed in 507 patients presenting either with vertigo (n=128; 23 of these patients suffered also from sensorineuronal hearing loss), other symptoms related to the inner ear, such as hearing loss or tinnitus (n=183) or symptoms unrelated to the labyrinth (n=196). All images were reviewed for presence of dehiscence of the bone, overlying the semicircular canals. Twenty-nine patients had superior semicircular canal dehiscence. Of these patients, 83% presented with vertigo, 10% with hearing loss or tinnitus and the remaining 7% with symptoms unrelated to the inner ear. In 23 patients dehiscence of the posterior semicircular canal was encountered. Of these patients, 86% presented with vertigo, 9% with hearing loss or tinnitus and 5% with symptoms unrelated to the inner ear. Defects of the bony overly are found at the posterior semicircular canal, in addition to the recently introduced superior canal dehiscence syndrome. Significant prevalence of vertigo in these patients suggests that posterior semicircular canal dehiscence can cause vertigo, similar to superior semicircular canal dehiscence. (orig.)

  18. An in vitro model to investigate filling of lateral canals.

    Science.gov (United States)

    Venturi, Mauro; Di Lenarda, Roberto; Prati, Carlo; Breschi, Lorenzo

    2005-12-01

    Aims of this work were to examine lateral canals in extracted teeth, to propose a new technique to produce artificial lateral canals, and to compare two obturation techniques. Cleared roots were examined to record measure and shape of lateral canals. Artificial lateral canals were prepared on human demineralized teeth before final clearing. Specimens were divided in two groups: canals of group 1 were filled with Schilder's technique, canals of group 2 were filled with vertical compaction with apical backfilling. Stereomicroscopic analysis of lateral canal filling revealed lower filling rates in apical canals compared to coronal ones and higher filling rates with "vertical compaction with apical backfilling" compared to Schilder's group. The tested procedure appears to be a reliable technique to obtain standardized lateral canals and to compare filling procedures.

  19. A radiographic study of mandibular canal

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Won Chul; Lee, Sang Rae [Dept. of Oral Radiology, Division of Dentistry, Kyung Hee University, Seoul (Korea, Republic of)

    1987-11-15

    The author invested the gonial angle, the angle of mandibular and mental canal to the lower border of the mandible, and a relationship of the position of the mandibular canal to the root apex of the posterior teeth and the cortical plate of the lower of the mandible. The materials consisted of 458 pantomograms in male and female aged 11-40 and divided into 5 groups at year intervals and subdivided into 3 groups by gonial angle. The results were as follows: 1. The gonial angle decreased with age, but slight increase occurred over 26-30 years. 2. The average angle of the mandibular canal to the lower border of the mandible was 151.6 degree and did not correlate with age. 3. The average angle of the mental canal to the lower border of the mandible was 36.9 degree and didn't correlate with age. 4. The angles of mandibular and mental canal to the lower border of mandible correlated with gonial angle. 5. The distance from the root apex of the posterior teeth to the upper wall mandibular canal was most short at the region of the distal root of the mandibular second and increased with age at the region of the mandibular second molar. 6. The distance from the lower wall of the mandibular canal to the cortical plate of the lower border of the mandibule was most short at the region of the mesial root of the mandibular first molar and didn't correlate with age.

  20. Radiological Review Studies On Ismailia Canal Ecology

    International Nuclear Information System (INIS)

    The present work is a brief review of pr-studies carried out on Ismailia Canal, Egypt, water ecosystem. Ismailia Canal water body is a bicarbonate stream with slight seasonal variations in its water chemical constituents. The canal water pH in all the stream locations are below 8.3 with low suspended matter(SM) content (22-33 mg.l-1). The mineralogical analysis of the canal bottom sediments consist mainly of quartz, smectite and kaolinite minerals. The γ- spectroscopic identification showed traces of naturally occurring radio nuclides (238U, 232Th and 40K). The average activity level of the dry samples ranged from 12 to 89 Bq.Kg-1 for the detected natural radio nuclides. Some parameters affected the sorption behaviour of radio nuclides on suspended matters and bottom sediments; such as solution pH, SM concentration, sediment grain size, carrier concentration and competing ions were studied. The reaction rates were investigated for each radionuclide studied. The distribution of the studied radio nuclides, between the liquid phase and the sediments phase was investigated, for both flowing and static systems. For both flowing and non-flowing (static), the depth penetration of the studied radio nuclides within the bottom sediment layers were found to vary from one radionuclide to the other. The total capacities of bottom sediments and the suspended matter were found to be low. As Ismailia Canal is an important source of water for public domestic uses, irrigation animals and the aquatic species; these situations have led to state that it is not recommended to release any liquid radioactive wastes to this canal. Furthermore, periodical radiometric analysis for the canal water and its components should be carried out.

  1. An ex vivo comparison of detection ability of three methods in discovering of MB2 canal in maxillary molars

    Directory of Open Access Journals (Sweden)

    Ghorbanzadeh A.

    2009-11-01

    Full Text Available "nBackground and Aim: A considerable percentage of failure in Endodontic treatments in maxillary molars is attributed to undiscovered second mesiobuccal canal (MB2.There are different methods for discovering and accessing to this canal. The purpose of this ex vivo study was to compare the detection ability of three methods (direct look, fiberoptic loup and surgical microscope to find MB2 after troughing with ultrasonic. "nMaterials and Methods: In this experimental study, we selected 90 extracted maxillary molars (45 first and 45 second molars in which after access cavity preparation MB2 canal was not discovered by direct vision and endodontic explorer. They were divided into 3 groups (n=30. The dentinal shelf between mesiobuccal and palatal canals was eliminated by an endodontic ultrasonic tip (troughing. After that, first group was searched by direct vision, second group by a loup and fiberoptic light and third group by dental operating microscope. Data were analyzed, specificity and sensitivity were calculated. "nResults: The results showed that 21%, 61%, and 92% of MB2 canals after troughing was found by direct vision, fiberoptic loup, and surgical microscope, respectively. "nConclusion: Based on the results of this study, surgical microscope and loup with fiberoptic are preferred methods for discovering MB2 canal. Troughing with ultrasonic can help find MB2 canal in all methods.

  2. The Kra Canal and Southeast Asian Relations

    Directory of Open Access Journals (Sweden)

    Rini Suryati Sulong

    2012-01-01

    Full Text Available This paper is a conceptual study that attempts to analyse the possible effects of the development of the Kra Isthmus Canal on ASEAN relations. The Kra Canal would constitute a mega-project, a passageway that would connect the Andaman Sea and the Gulf of Thailand at the Isthmus of Kra, Thailand. Although the proposed Kra Canal is projected to provide many economic and trade benefits to Thailand, and to the region as a whole, steps toward its development have yet to be taken. There has been much debate over the costs for trade, the costs for the environment, national and regional security concerns, as well as major concerns related to political and economic relations in the region. Therefore, one of the main purposes of this study is to contribute to the debate on the possible impact of the devel-opment of the Kra Canal on ASEAN’s regional relations. In particular, it proposes that the development of the Kra Canal could threaten regional solidarity as it would physically divide maritime Southeast Asia from main-land Southeast Asia, which would ultimately result in an economic, cultural and political divide of ASEAN itself.

  3. The efficacy of adductor canal blockade after minor arthroscopic knee surgery

    DEFF Research Database (Denmark)

    Espelund, M; Fomsgaard, J S; Haraszuk, J;

    2014-01-01

    BACKGROUND: Adductor canal blockade (ACB) has been demonstrated to be effective in the treatment of post-operative pain after major knee surgery. We hypothesised that the ACB would reduce pain and analgesic requirements after minor arthroscopic knee surgery. METHODS: Seventy-two patients schedule...

  4. Limitations of temperature measurement in the aural canal with an ear mould integrated sensor

    NARCIS (Netherlands)

    Teunissen, L.P.J.; Haan, A. de; Koning, J.J. de; Clairbois, H.E.; Daanen, H.A.M.

    2011-01-01

    Aural canal temperature measurement using an ear mould integrated sensor (Tac) might be a method suited for continuous non-invasive core temperature estimation in operational settings. We studied the effect of ambient temperature, wind and high intensity exercise on Tac and its ability to predict es

  5. Hemangiopericytoma in the vertebral canal of thoracic segments:report of a rare case

    Institute of Scientific and Technical Information of China (English)

    Jie Zhou; Yong Zhou; Hulin Ma; Zhiyun Li; Jiaojing He; Die Zhu; Xiaodong Qu

    2015-01-01

    In this paper, we explore the diagnosis and treatment of hemangiopericytoma (HPC). A rare case of HPC in the vertebral canal of thoracic segments is reported, and the clinical features as wel as treatment ap-proaches of similar cases in the literature are discussed. In the present case, we operatively resected the tumor and performed postoperative radiation therapy, with good treatment results.

  6. Lumbar spinal canal size of sciatica patients

    Energy Technology Data Exchange (ETDEWEB)

    Hurme, M.; Alaranta, H.; Aalto, T.; Knuts, L.R.; Vanharanta, H.; Troup, J.D.G. (Turku City Hospital (Finland). Dept. of Surgery; Social Insurance Institution, Turku (Finland). Rehabilitation Research Centre; Helsinki Univ. (Finland). Dept. of Physical Medicine and Rehabilitation; Liverpool Univ. (UK). Dept. of Orthopaedic and Accident Surgery)

    Seven measures at the three lowest lumbar interspaces were recorded from conventional radiographs of the lumbar spines of 160 consecutive patients with low back pain and sciatica admitted for myelography and possible surgery. Eighty-eight patients were operated upon for disc herniation, and of the conservatively-treated 72 patients, 18 had a pathologic and 54 a normal myelogram. The results were evaluated after one year using the occupational handicap scales of WHO. Correlations of radiographic measures to stature were moderate and to age small. After adjusting for stature and age, only the male interpedicular distances and the antero-posterior diameter of intervertebral foramen at L3 were greater than those of females. The males with a pathologic myelogram had smaller posterior disc height at L3 and a smaller interarticular distance at L3 and L4 than those with normal myelogram, likewise the midsagittal diameter at L3 and L4 in females. In all patients other measures besides posterior disc height were smaller than those for low back pain patients (p<0.001) or for cadavers (p<0.001). The only correlation between measures and clinical manifestations was between pedicular length at L3 and limited straight leg raising. Where the disc material had been extruded into the spinal canal, the interpedicular distance was significantly wider. Only anterior disc height at L3 revealed differences between good and poor outcome one year after surgery, as did the interarticular distance at S1 in patients with normal myelogram after conservative treatment. (orig.).

  7. Management of curved root canals in endodontics: clinical case of retreatment

    International Nuclear Information System (INIS)

    The management of curved root canals in endodontics therapy has required time, patience and skill of the operator, and lots collaboration by the patient. Proper cleaning, disinfection, conformation and root canal filling, in most cases, has prevented the appearance of lesions of bacterial origin to apical or maintenance of these lesions in teeth that are portrayed level. A clinical case is described of retreatment of a first mandibular molar by conventional endodontic treatment with their respective steps, to achieve signs of tissue repair at the apical level. (author)

  8. Clinical analysis of early complioations in senile people with severe lumbar spinal canal stenosis at early post-operation stage%老年重度腰椎管狭窄症围术期特点及其术后早期并发症

    Institute of Scientific and Technical Information of China (English)

    张新宇; 匡正达; 叶启彬

    2015-01-01

    目的:探讨老年重度腰椎管狭窄症围术期特点和术后早期并发症的处理方法。方法回顾性分析我院骨科2008-02至2013-12共184例老年重度腰椎管狭窄症的病历资料,总结术前合并症、术中出血量、手术时间、住院时间,观察术后早期并发症的出现情况,总结处理方法。结果患者平均(68.77±5.76)岁,平均住院时间(27.26±9.61)d,无围术期死亡病例,手术时间平均(3.09±1.09) h,术中出血量平均(618.60±366.50) ml,融合节段超过3个的106例(57.61%)。出现各种并发症合计119例(64.67%),按发生的比例依次排列为切口愈合不良、术后疼痛、全身状况不稳定、低血容量、脑脊液漏、神经根损伤和深静脉血栓形成,对所发生的并发症,均给予了积极有效的对应治疗,效果较好。结论老年重度腰椎管狭窄症患者的手术有一定的风险,但并非不能手术,做好术前准备和术后应对预案,可以提高围术期安全性。%Objective To investigate the peroperative characteristics and early complications in senile people with severe lum -bar spinal canal stenosis .Method From february 2008 to December 2013, a retrospective review of 184 patients with severe lumbar canal stenosis treated surgically with decompressional procedure was performed .Of these, 80 males, 104 females aging from 60~86 years (average of 68.77 ±5.76 years).All patrents underwent surgical decompression .Before operation, all cases consulted with in-ternal medical stuff for the proper treatment of concomitant diseases .The preoperative concomitant diseases , intraoperative bleeding volume, operative and hospitalization time were summarized .The appearance and management of complications at early post-operation stage were observed especially .Result The average hospital stay was 27.26 ±9.61 days.No death cases ocurred during peri-opera-tion.The average

  9. Synchronous rectal adenocarcinoma and anal canal adenocarcinoma

    Institute of Scientific and Technical Information of China (English)

    GU Jin; LI Jiyou; YAO Yunfeng; LU Aiping; WANG Hongyi

    2007-01-01

    It is difficult to distinguish a tectal carcinoma with anal metastases from coexistent synchronous anorectal carcinomas.The therapeutic strategy for rectal and anal carcinoma is so different that it should be clearly identified.Here,we report on the case of a 63-year-old man who presented with an upper-third rectal adenocarcinoma.Five months after resection,he developed an adenocarcinoma in the anal canal.The histological slides of both tumors were reviewed and immunohistochemical studies for cytokeratins(CKs)7 and 20 were performed.The index tumor demonstrated CK 7-/CK 20+and the second showed CK7+/CK20+.For this reason,we believe the present case had synchronous adenocarcinomas arising from anal canal and the rectum separately.It is very important to difierentiate the anorectal lesions pathologically because of the impact on the therapeutic options available,especially for the lesion arising in the anal canal.

  10. File list: His.CDV.50.AllAg.Atrioventicular_canals [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.CDV.50.AllAg.Atrioventicular_canals mm9 Histone Cardiovascular Atrioventicular canal...s http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/His.CDV.50.AllAg.Atrioventicular_canals.bed ...

  11. File list: Unc.CDV.05.AllAg.Atrioventicular_canals [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Unc.CDV.05.AllAg.Atrioventicular_canals mm9 Unclassified Cardiovascular Atrioventicular canal...s http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Unc.CDV.05.AllAg.Atrioventicular_canals.bed ...

  12. File list: His.CDV.05.AllAg.Atrioventicular_canals [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.CDV.05.AllAg.Atrioventicular_canals mm9 Histone Cardiovascular Atrioventicular canal...s http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/His.CDV.05.AllAg.Atrioventicular_canals.bed ...

  13. File list: Unc.CDV.50.AllAg.Atrioventicular_canals [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Unc.CDV.50.AllAg.Atrioventicular_canals mm9 Unclassified Cardiovascular Atrioventicular canal...s http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Unc.CDV.50.AllAg.Atrioventicular_canals.bed ...

  14. File list: Unc.CDV.10.AllAg.Atrioventicular_canals [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Unc.CDV.10.AllAg.Atrioventicular_canals mm9 Unclassified Cardiovascular Atrioventicular canal...s http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Unc.CDV.10.AllAg.Atrioventicular_canals.bed ...

  15. File list: His.CDV.10.AllAg.Atrioventicular_canals [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.CDV.10.AllAg.Atrioventicular_canals mm9 Histone Cardiovascular Atrioventicular canal...s http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/His.CDV.10.AllAg.Atrioventicular_canals.bed ...

  16. File list: Unc.CDV.20.AllAg.Atrioventicular_canals [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Unc.CDV.20.AllAg.Atrioventicular_canals mm9 Unclassified Cardiovascular Atrioventicular canal...s http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Unc.CDV.20.AllAg.Atrioventicular_canals.bed ...

  17. File list: His.CDV.20.AllAg.Atrioventicular_canals [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.CDV.20.AllAg.Atrioventicular_canals mm9 Histone Cardiovascular Atrioventicular canal...s http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/His.CDV.20.AllAg.Atrioventicular_canals.bed ...

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

    International Nuclear Information System (INIS)

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

  19. Measurement of cochlea to facial nerve canal with thin-section computed tomographic image.

    Science.gov (United States)

    Jiang, Ying; Liu, Xiangliang; Yao, Jihang; Tian, Yong; Xia, Changli; Li, Youqiong; Fu, Yan; Luo, Qi

    2013-03-01

    Facial nerve (FN) paralysis is a rare but devastating complication of cochlear implant surgery. This study aimed to measure the cupula of the cochlea to the tympanic segment of the FN canal, cupula of the cochlea to the mastoid segment of the FN canal, and the geniculate ganglion to provide a more secure and accurate orientation of the FN canal and to facilitate operation on the cochlea by avoiding potential damage to FN. Using computed tomography, we scanned skulls of 120 volunteers who suffer no cases of skull base lesions. Multiplane reconstruction images were prepared with high-resolution computed tomography. Preoperative evaluation of the FN anatomy within the temporal bone by high-resolution computed tomography helps in minimizing surgical trauma to the nerve, and these results can help guide clinical surgery on the cochlea.

  20. Gain-scheduling multivariable LPV control of an irrigation canal system.

    Science.gov (United States)

    Bolea, Yolanda; Puig, Vicenç

    2016-07-01

    The purpose of this paper is to present a multivariable linear parameter varying (LPV) controller with a gain scheduling Smith Predictor (SP) scheme applicable to open-flow canal systems. This LPV controller based on SP is designed taking into account the uncertainty in the estimation of delay and the variation of plant parameters according to the operating point. This new methodology can be applied to a class of delay systems that can be represented by a set of models that can be factorized into a rational multivariable model in series with left/right diagonal (multiple) delays, such as, the case of irrigation canals. A multiple pool canal system is used to test and validate the proposed control approach. PMID:27184416

  1. Three-Dimensional Printed Prosthesis for Repair of Superior Canal Dehiscence.

    Science.gov (United States)

    Kozin, Elliott D; Remenschneider, Aaron K; Cheng, Song; Nakajima, Hideko Heidi; Lee, Daniel J

    2015-10-01

    Outcomes following repair of superior canal dehiscence (SCD) are variable, and surgery carries a risk of persistent or recurrent SCD symptoms, as well as a risk of hearing loss and vestibulopathy. Poor outcomes may occur from inadequate repair of the SCD or mechanical insult to the membranous labyrinth. Repair of SCD using a customized, fixed-length prosthesis may address current operative limitations and improve surgical outcomes. We aim to 3-dimensionally print customized prostheses to resurface or occlude bony SCD defects. Dehiscences were created along the arcuate eminence of superior semicircular canals in cadaveric temporal bones. Prostheses were designed and created using computed tomography and a 3-dimensional printer. The prostheses occupied the superior semicircular canal defect, reflected in postrepair computed tomography scans. This novel approach to SCD repair could have advantages over current techniques. Refinement of prosthesis design and materials will be important if this approach is translated into clinical use.

  2. Stratification and enumeration of Boolean functions by canalizing depth

    Science.gov (United States)

    He, Qijun; Macauley, Matthew

    2016-01-01

    Boolean network models have gained popularity in computational systems biology over the last dozen years. Many of these networks use canalizing Boolean functions, which has led to increased interest in the study of these functions. The canalizing depth of a function describes how many canalizing variables can be recursively "picked off", until a non-canalizing function remains. In this paper, we show how every Boolean function has a unique algebraic form involving extended monomial layers and a well-defined core polynomial. This generalizes recent work on the algebraic structure of nested canalizing functions, and it yields a stratification of all Boolean functions by their canalizing depth. As a result, we obtain closed formulas for the number of n-variable Boolean functions with depth k, which simultaneously generalizes enumeration formulas for canalizing, and nested canalizing functions.

  3. Stratification and enumeration of Boolean functions by canalizing depth

    CERN Document Server

    He, Qijun

    2015-01-01

    Boolean network models have gained popularity in computational systems biology over the last dozen years. Many of these networks use canalizing Boolean functions, which has led to increased interest in the study of these functions. The canalizing depth of a function describes how many canalizing variables can be recursively picked off, until a non-canalizing function remains. In this paper, we show how every Boolean function has a unique algebraic form involving extended monomial layers and a well-defined core polynomial. This generalizes recent work on the algebraic structure of nested canalizing functions, and it yields a stratification of all Boolean functions by their canalizing depth. As a result, we obtain closed formulas for the number of n-variable Boolean functions with depth k, which simultaneously generalizes enumeration formulas for canalizing, and nested canalizing functions.

  4. Surgical endodontic management of infected lateral canals of maxillary incisors

    Science.gov (United States)

    2015-01-01

    This case report presents surgical endodontic management outcomes of maxillary incisors that were infected via the lateral canals. Two cases are presented in which endodontically-treated maxillary central incisors had sustained lateral canal infections. A surgical endodontic treatment was performed on both teeth. Flap elevation revealed vertical bone destruction along the root surface and infected lateral canals, and microscopy revealed that the lateral canals were the origin of the lesions. After the infected lateral canals were surgically managed, both teeth were asymptomatic and labial fistulas were resolved. There were no clinical or radiographic signs of surgical endodontic management failure at follow-up visits. This case report highlights the clinical significance and surgical endodontic management of infected lateral canal of maxillary incisor. It is important to be aware of root canal anatomy variability in maxillary incisors. Maxillary central incisors infected via the lateral canal can be successfully managed by surgical endodontic treatment. PMID:25671217

  5. Removal action report on the Building 3001 canal at Oak Ridge National Laboratory, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-05-01

    Oak Ridge National Laboratory (ORNL) is a federal facility managed by Lockheed Martin C, Energy Research, Inc., for the U.S. Department of Energy (DOE). ORNL on the Oak Ridge Reservation in East Tennessee at the Anderson and Roane County lines, approximately 38 km (24 miles) west of Knoxville, Tennessee, and 18 km (11 miles) southwest of downtown Oak Ridge. The Oak Ridge Graphite Reactor and its storage and transfer canal are located in Bldg. 3001 in the approximate center of Waste Area Grouping I in the ORNL main complex. 4:1 The Bldg. 3001 Storage Canal is an L-shaped, underground, reinforced-concrete structure running from the back and below the Graphite Reactor in Bldg. 3001 to a location beneath a hot cell in the adjacent Bldg. 3019. The Graphite Reactor was built in 1943 to produce small quantities of plutonium and was subsequently used to produce other isotopes for medical research before it was finally shut down in 1963. The associated canal was used to transport, under water, spent fuel slugs and other isotopes from the back of the reactor to the adjacent Bldg. 31319 hot cell for further processing. During its operation and years subsequent to operation, the canal`s concrete walls and floor became contaminated with radioisotopes from the water.This report documents the activities involved with replacing the canal water with a solid, controlled, low-strength material (CLSM) in response to a Comprehensive Environmental Response, Compensation, and Liability Act non-time-critical removal action.

  6. Viscoelastic assessment of anal canal function using acoustic reflectometry

    DEFF Research Database (Denmark)

    Mitchell, Peter J; Klarskov, Niels; Telford, Karen J;

    2012-01-01

    Anal acoustic reflectometry is a new reproducible technique that allows a viscoelastic assessment of anal canal function. Five new variables reflecting anal canal function are measured: the opening and closing pressure, opening and closing elastance, and hysteresis.......Anal acoustic reflectometry is a new reproducible technique that allows a viscoelastic assessment of anal canal function. Five new variables reflecting anal canal function are measured: the opening and closing pressure, opening and closing elastance, and hysteresis....

  7. Discrimination potential of root canal treated tooth in forensic dentistry.

    Science.gov (United States)

    Khalid, K; Yousif, S; Satti, A

    2016-01-01

    Forensic Odontology is a vital component of forensic science and one branch involves the application of dental science to the identification of unknown human remains. The aim of this study is to investigate the discriminatory potential for identification of the radiographic morphology of obturated single root canals. Thirty periapical radiographs of patients having endodontic treatment of single rooted canals were selected randomly from the data bank of the digital X- ray system present in the restorative department, University of Science and Technology, Sudan. The post-operative radiographs were considered as an ant-mortem data "Set 1". Ten radiographs from the thirty were reprinted, labelled from (A-J) and considered as a post-mortem data "Set 2". This post-mortem group of 10 radiographs "Set 2" would be compared with the ante-mortem group of 30 radiographs comprising "Set 1". These two sets of radiographs would be examined by 40 dentally trained personnel. The thirty radiographs comprising "Set 1" and the 10 radiographs comprising "Set 2" were provided to each of the examiners who were asked to match the individual post-mortem radiographs ("Set 2") with the ante-mortem radiographs ("Set1"). The result demonstrated that 34 examiners achieved a success rate of 100%, 4 examiners achieved a success rate of 97.5% (1 mismatch) and 2 examiners achieved a success rate of 95% (2 mismatches). The radiographic images of obturated single-rooted teeth in this study were shown to have highly- specific morphological features. It is proposed that, in cases where the ante and post-mortem radiographs of a single-rooted obturated canal show similar morphology, this commonality of morphology can be used as a tool in the identification process. PMID:27350699

  8. Computed tomography of the thoracic canal. Experimental and clinical studies

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, S. (Yamaguchi Univ., Ube (Japan). School of Medicine)

    1981-05-01

    Under the adequate CT condition, thoracic canal was studied in twelve normal cases, nine cases of cervical myelopathy with developmental cervical canal stenosis and four cases of thoracic myelopathy with ossification of thoracic yellow ligament. The results were as follows. 1) The adequate condition for delineation of thoracic canal seemed to be nearly 400 EMI units in window width and 150 in level. Scanning angle was permitted within about 10/sup 0/. Bony thoracic canal was well scanned at the center of vertebral body. 2) The configulation of the normal thoracic canal was oval at Th/sub 1/, Th/sub 2/ levels and round at Th/sub 3/-Th/sub 10/ and large oval at Th/sub 11/, Th/sub 12/. The sagittal diameter was almost fixed at each level and the transverse diameter was large at upper and lower levels and small at middle levels. 3) Thoracic canal was narrowed in the cases of cervical myelopathy with developmental cervical canal stenosis especially in sagittal diameter, but not narrowed in transverse diameter. Three of four cases who had myelopathy with ossification of thoracic yellow ligament had narrow canals. 4) There was a good relation between sagittal diameter of cervical canal and thoracic canal. 5) There was a good relation between sagittal diameter of thoracic canal measured by conventional radiographs (Hattori's method) and CT scans. The author thinks that Hattori's method is useful to diagnose the thoracic canal stenosis.

  9. 21 CFR 872.3820 - Root canal filling resin.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Root canal filling resin. 872.3820 Section 872...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3820 Root canal filling resin. (a) Identification. A root canal filling resin is a device composed of material, such as methylmethacrylate,...

  10. Newer Root Canal Irrigants in Horizon: A Review

    OpenAIRE

    Prashant P. Jaju; Sushma Jaju

    2011-01-01

    Sodium hypochloride is the most commonly used endodontic irrigant, despite limitations. None of the presently available root canal irrigants satisfy the requirements of ideal root canal irrigant. Newer root canal irrigants are studied for potential replacement of sodium hypochloride. This article reviews the potential irrigants with their advantages and limitations with their future in endodontic irrigation.

  11. Newer Root Canal Irrigants in Horizon: A Review

    Directory of Open Access Journals (Sweden)

    Sushma Jaju

    2011-01-01

    Full Text Available Sodium hypochloride is the most commonly used endodontic irrigant, despite limitations. None of the presently available root canal irrigants satisfy the requirements of ideal root canal irrigant. Newer root canal irrigants are studied for potential replacement of sodium hypochloride. This article reviews the potential irrigants with their advantages and limitations with their future in endodontic irrigation.

  12. Nerve canals at the fundus of the internal auditory canal on high-resolution temporal bone CT

    Energy Technology Data Exchange (ETDEWEB)

    Ji, Yoon Ha; Youn, Eun Kyung; Kim, Seung Chul [Sungkyunkwan Univ., School of Medicine, Seoul (Korea, Republic of)

    2001-12-01

    To identify and evaluate the normal anatomy of nerve canals in the fundus of the internal auditory canal which can be visualized on high-resolution temporal bone CT. We retrospectively reviewed high-resolution (1 mm thickness and interval contiguous scan) temporal bone CT images of 253 ears in 150 patients who had not suffered trauma or undergone surgery. Those with a history of uncomplicated inflammatory disease were included, but those with symptoms of vertigo, sensorineural hearing loss, or facial nerve palsy were excluded. Three radiologists determined the detectability and location of canals for the labyrinthine segment of the facial, superior vestibular and cochlear nerve, and the saccular branch and posterior ampullary nerve of the inferior vestibular nerve. Five bony canals in the fundus of the internal auditory canal were identified as nerve canals. Four canals were identified on axial CT images in 100% of cases; the so-called singular canal was identified in only 68%. On coronal CT images, canals for the labyrinthine segment of the facial and superior vestibular nerve were seen in 100% of cases, but those for the cochlear nerve, the saccular branch of the inferior vestibular nerve, and the singular canal were seen in 90.1%, 87.4% and 78% of cases, respectiveIy. In all detectable cases, the canal for the labyrinthine segment of the facial nerve was revealed as one which traversed anterolateralIy, from the anterosuperior portion of the fundus of the internal auditory canal. The canal for the cochlear nerve was located just below that for the labyrinthine segment of the facial nerve, while that canal for the superior vestibular nerve was seen at the posterior aspect of these two canals. The canal for the saccular branch of the inferior vestibular nerve was located just below the canal for the superior vestibular nerve, and that for the posterior ampullary nerve, the so-called singular canal, ran laterally or posteolateralIy from the posteroinferior aspect of

  13. Shaping ability of ProFile rotary nickel-titanium instruments with ISO sized tips in simulated root canals: Part 2.

    Science.gov (United States)

    Bryant, S T; Thompson, S A; al-Omari, M A; Dummer, P M

    1998-07-01

    The aim of this study was to determine the shaping ability of ProFile 0.04 taper rotary nickel-titanium instruments with ISO sized tips in simulated canals. A total of 40 simulated root canals made up of four different shapes in terms of angle and position of curvature were prepared by ProFile instruments using the 'crown down' approach recommended by the manufacturer. Part 2 of this two-part report describes the efficacy of the instruments in terms of prevalence of canal aberrations, the amount and direction of canal transportation and the overall post-operative shape. Out of 37 completed specimens 9 zips (24%) and one ledge (3%) were created, but no perforations or danger zones were found. There were significant differences (P canal shapes for the incidence of zips and elbows but not for their distance from the end-point of preparation. At specific positions along the canal length there were significant differences between the canal types in terms of their mean total width; overall, at the end-point of preparation and along the curved portion of the canals those specimens with 40 degrees curves were widest. This trend continued for the width of material removed from the outer aspect of the canal curves, whereas along the inner aspect of curves more material was removed in the 20 degrees canals. Overall, transportation was towards the outer aspect of the curve at the end-point of preparation and along the curved portion of canals but more balanced along the straight coronal section. Absolute transportation was small and below 0.1 mm at every position including the zips. Under the conditions of this study, ProFile nickel-titanium rotary instruments with ISO sized tips produced a larger number of zips than expected; however, the degree of zipping was limited and relatively minor. PMID:9823118

  14. Infrared tympanic temperature and ear canal morphology

    NARCIS (Netherlands)

    Daanen, H.A.M.

    2006-01-01

    Several publications indicate that the infrared tympanic temperature (IRTT) underestimates the core temperature of the body when the ear canal is long, curvy and narrow. In order to quantify these observations, a study was performed in 10 subjects. The IRTT was determined and compared to the oesopha

  15. The crazy project – Canal Istanbul

    Directory of Open Access Journals (Sweden)

    Seda Kundak

    2011-10-01

    Full Text Available It was late April 2011 when “the Crazy Project - Canal Istanbul” was proposed by the Prime Minister of Turkey, during his election campaign.  Although the idea of an artificial canal is not new, since it is initiated without any consensus between the people and institutions in Istanbul, the project immediately set a large number of debates. These vary from the legitimacy of decentralization of governance, to potential impacts of the canal on international politics, economy, environment and urban life.  Regarding past infrastructure projects in Istanbul, such large scale investments have caused extensive acceleration in construction sector in one hand and social and economic shifts on the other.  In this paper, the Canal Istanbul Project is evaluated according to basic motivations and claims of the PM, multi-perspective view through challenges and limitation that the project is likely to face with and speculations on implementation approach. The final discussion on the project is based on benefits/losses of Istanbul once the project will be implemented.

  16. Note on Tendipedidae of the Suez Canal

    NARCIS (Netherlands)

    Kruseman, G.

    1949-01-01

    Mr. A. C. V. VAN BEMMEL and Dr. A. DIAKONOFF of the Buitenzorg Museum (Java) collected Tendipedidae, which were attracted by artificial lights, when they passed the Suez Canal on 8-XI-1937 and 16-V-1939 respectively. This very interesting collection, containing some new species, was sent to me for d

  17. Assessment of the wetting behavior of three different root canal sealers on root canal dentin

    OpenAIRE

    Muralidhar Tummala; Veeramachaneni Chandrasekhar; A Shashi Rashmi; Kundabala, M; Vasudev Ballal

    2012-01-01

    Aim: The objective of the present study was to evaluate and compare the wetting behavior of three different root canal sealers on the root canal dentin surface treated with irrigants and their combination. Materials and Methods: Decoronation and apical third resections of 27 extracted single-rooted human mandibular premolars were done. The roots were then split longitudinally into two halves, and randomly assigned into three treatment groups (n=18). The root dentin surfaces in Group1, Gro...

  18. Use of versapoint to refashion the cervical canal to overcome unusually difficult embryo transfers and improve in-vitro fertilization-embryo transfer outcome: A case series

    Directory of Open Access Journals (Sweden)

    Nalini Mahajan

    2011-01-01

    Full Text Available Background : Smooth atraumatic embryo transfer is paramount for the success of in-vitro fertilization (IVF. In difficult cases, cervical canal manipulation may be required. Aim : To see if surgical correction of the cervical canal or cervical canal refashioning could improve ease of embryo transfer. Setting : Private infertility and IVF hospital. Design : Prospective study. Materials and Methods : Patients: 11 women with failed 1-3 IVF cycles with history of extremely difficult embryo transfers (ETs despite undergoing cervical dilatation in the cycle prior to IVF. Interventions : Operative hysteroscopy using Versapoint for refashioning of the cervical canal. Main Outcome Measures : Ease of ET in the subsequent IVF cycle. Secondary outcome measure was to assess reproductive outcome. Results : Easy and atraumatic ET in the IVF cycle after procedure in 100% patients. PR was 46.5%. Conclusions : Use of Versapoint for refashioning the cervical canal can improve the quality of ET and PR.

  19. MR determination of neonatal spinal canal depth

    Energy Technology Data Exchange (ETDEWEB)

    Arthurs, Owen, E-mail: owenarthurs@uk2.net [Centre for Cardiovascular MR, Great Ormond Street Hospital for Children, London WC1N 3JH (United Kingdom); Thayyil, Sudhin, E-mail: s.thayyil@ucl.ac.uk [Academic Neonatology, Institute for Women' s Health, London WC1E 6AU (United Kingdom); Wade, Angie, E-mail: a.wade@ucl.ac.uk [Centre for Paediatric Epidemiology and Biostatistics, UCL Institute of Child Health, London (United Kingdom); Chong, W.K., E-mail: Kling.Chong@gosh.nhs.uk [Paediatric Neuroradiology, Great Ormond Street Hospital for Children, London (United Kingdom); Sebire, Neil J., E-mail: Neil.Sebire@gosh.nhs.uk [Histopathology, Great Ormond Street Hospital for Children, London WC1E 6AU (United Kingdom); Taylor, Andrew M., E-mail: a.taylor76@ucl.ac.uk [Centre for Cardiovascular MR, Cardiorespiratory Unit, Great Ormond Street Hospital for Children and UCL Institute of Cardiovascular Science, London WC1E 6AU (United Kingdom)

    2012-08-15

    Objectives: Lumbar punctures (LPs) are frequently performed in neonates and often result in traumatic haemorrhagic taps. Knowledge of the distance from the skin to the middle of the spinal canal (mid-spinal canal depth - MSCD) may reduce the incidence of traumatic taps, but there is little data in extremely premature or low birth weight neonates. Here, we determined the spinal canal depth at post-mortem in perinatal deaths using magnetic resonance imaging (MRI). Patients and methods: Spinal canal depth was measured in 78 post-mortem foetuses and perinatal cases (mean gestation 26 weeks; mean weight 1.04 kg) at the L3/L4 inter-vertebral space at post-mortem MRI. Both anterior (ASCD) and posterior (PSCD) spinal canal depth were measured; MSCD was calculated and modelled against weight and gestational age. Results: ASCD and PSCD (mm) correlated significantly with weight and gestational age (all r > 0.8). A simple linear model MSCD (mm) = 3 Multiplication-Sign Weight (kg) + 5 was the best fit, identifying an SCD value within the correct range for 87.2% (68/78) (95% CI (78.0, 92.9%)) cases. Gestational age did not add significantly to the predictive value of the model. Conclusion: There is a significant correlation between MSCD and body weight at post-mortem MRI in foetuses and perinatal deaths. If this association holds in preterm neonates, use of the formula MSCD (mm) = 3 Multiplication-Sign Weight (kg) + 5 could result in fewer traumatic LPs in this population.

  20. 77 FR 28767 - Drawbridge Operation Regulation; Hood Canal, WA

    Science.gov (United States)

    2012-05-16

    ... rush hour road traffic by reducing bridge openings, thereby reducing traffic queues and delays due to... available for inspection or copying at the Docket Management Facility (M-30), U.S. Department of... (77 FR 12514). We received 17 comments on the proposed ] rule. No public meeting was requested,...

  1. Comparison of different retreatment techniques and root canal sealers: a scanning electron microscopic study

    Directory of Open Access Journals (Sweden)

    Neslihan Simsek

    2014-05-01

    Full Text Available The aim of this study was to evaluate the effectiveness of two retreatment techniques, in terms of the operating time and scanning electron microscopy (SEM results, in removing three different root canal sealers from root canals that were previously filled with gutta-percha. Sixty extracted single-rooted human premolars were divided into three groups and filled with iRoot SP, MM Seal, and AH Plus sealers, along with gutta-percha, through a lateral compaction technique. Root canal fillings of the samples were removed by ESI ultrasonic tips or R-Endo files. The time to reach the working length was recorded. Longitudinally sectioned samples were examined under SEM magnification. Each picture was evaluated in terms of the residual debris. Data were statistically analyzed with the Kruskall-Wallis test. No statistically significant differences were found in terms of operating time (p>0.05. Significant differences in the number of debris-free dentinal tubules were found among the root canal thirds, but this finding was not influenced by the experimental group (p < 0.05. Resin sealer tags were observed inside the dentinal tubules in the MM Seal group. Under the conditions of this study, it may be established that there was no difference among the sealers and retreatment techniques.

  2. Developmentof the safety monitoring system of hydraulic structuresof the Moscow canal

    Directory of Open Access Journals (Sweden)

    Levachev Stanislav Nikolaevich

    2015-05-01

    Full Text Available The basis of the enterprise “Moscow Canal” in its present state is the canal Moscow - Volga constructed in 1937. Today “Moscow Canal” is the biggest water transport and water industry complex. It has 10 filiations and solves a substantial complex of tasks. One of the most important part of hydraulic structures operation is their observation or monitoring of their safety, which gives us timely and adequate picture of their work and helps to forecast and prevent emergency situations.The article is devoted to the development of the monitoring system of the waterworks of the Moscow canal beginning with the moment of its construction to the present time, the observation analysis of the condition of the walls of canal locks chambers, lock no. 2 where destructive processes in the operation of the walls were first discovered and different methods of liquidation of their development were made. The main problems in the field of monitoring of hydrotechnical structures of the Moscow canal are identified basing on the analysis of the observations.

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

    Science.gov (United States)

    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. PMID:23730547

  4. Comparison of the rheological properties of four root canal sealers

    Institute of Scientific and Technical Information of China (English)

    Seok Woo Chang; Kwang Shik Bae; Young-Kyu Lee; Qiang Zhu; Won Jun Shon; Woo Cheol Lee; Kee Yeon Kum; Seung Ho Baek; In Bog Lee; Bum-Soon Lim

    2015-01-01

    The flowability of a root canal sealer is clinically important because it improves the penetration of the sealer into the complex root canal system. The purpose of this study was to compare the flowabilities of four root canal sealers, measured using the simple press method (ISO 6876), and their viscosities, measured using a strain-controlled rheometer. A newly developed, calcium phosphate-based root canal sealer (Capseal) and three commercial root canal sealers (AH Plus, Sealapex and Pulp Canal Sealer EWT) were used in this study. The flowabilities of the four root canal sealers were measured using the simple press method (n55) and their viscosities were measured using a strain-controlled rheometer (n55). The correlation between these two values was statistically analysed using Spearman’s correlation test. The flow diameters and the viscosities of the root canal sealers were strongly negatively correlated (r520.8618). The viscosity of Pulp Canal Sealer EWT was the lowest and increased in the following order:AH Plus,Sealapex,Capseal (P,0.05). All of the tested root canal sealers showed characteristic time-and temperature-dependent changes in their rheological properties. The viscosities measured using the strain-controlled rheometer were more precise than the flowabilities measured using the simple press method, suggesting that the rheometer can accurately measure the rheological properties of root canal sealers.

  5. Morphology of the mandibular canal and the angulation between the mandibular and mental canals in dry skulls

    DEFF Research Database (Denmark)

    Pálsson, S R; Kjaer, I

    2008-01-01

    -angles. In order to analyse internal morphology, a metallic pin was placed in the mental canal on the left side before radiography. The angle between the mental and the mandibular canals was termed the 'mental angle' and that expressing the curvature of the mandibular canal, the 'mandibular angle'. Spearman......-angles. The findings show that the internal courses of the mandibular and mental canals are interrelated. They also indicated that the course and morphology of the mandibular canal are interrelated with external mandibular morphology....

  6. Diagnosis and treatment of hematoma-induced spinal cord injury after operation for fluorosis cervical canal stenosis%氟骨病颈椎管狭窄症术后血肿致脊髓损伤的诊治对策

    Institute of Scientific and Technical Information of China (English)

    夏英鹏; 申庆丰; 徐天同; 李辉南

    2013-01-01

    Objective To study the causes of hematoma-induced spinal cord injury after surgical treatment of fluorosis cervical canal stenosis (FCCS) so as to conclude the methods for early diagnosis and treatment.Methods A retrospective review was conducted on 329 cases of FCCS undergone expansive laminoplasty (ELOP) between 2006 and 2009.Eighteen out of the 329 cases presented with neural deterioration in postoperative 2 weeks,including l 1 males and 7 females at age of 45-73 years (mean 56.9 years).MRI scan at postoperative 1-5 days confirmed that the injury cause was hematoma formation (incidence of 5.47%).Once the definite diagnosis was made,immediate local puncture decompression,immobilization in the prone position as well as a timely second surgical probe and spinal decompression were performed.Results Nerve symptom of the 18 cases obtained different degree of recovery.Japanese Orthopedic Association (JOA) score promoted from preoperative (7.44 ± 1.25) points to (12.6 ± 2.1)points at 12 months after second operation.Scatter plot between time of definite diagnosis and improvement value in JOA score before and after the second operation was drawn so as to establish linear equation (Y =6.240 7-0.777 8X(F =9.89,P <0.01).As a result,the two variables presented a negative linear relationship,which suggested a better outcome after early treatment than delayed treatment.Conclusions Hematoma compression is the main cause of spinal cord injury following operation for FCCS patients.Strict hematosis and alternate lateral clinostatism after operation were effective prevention methods.Besides,early diagnosis and timely treatment are critically important.%目的 分析氟骨病颈椎管狭窄症(flurosis cervical canal stenosis,FCCS)术后血肿造成脊髓损伤的原因,总结早期诊断和治疗方法. 方法 回顾性分析2006-2009年采用后路单开门椎管成形术(expansive laminoplasty,ELOP)治疗的FCCS患者329例.18例患者术后2周内出

  7. Root canal preparation of calcified root canals in the elderly patients%老年患者钙化根管的预备

    Institute of Scientific and Technical Information of China (English)

    申玲; 黄静华; 黄碧杰; 朱燕梅

    2014-01-01

    Objective: To observe the condition of the root canal calcification of the elderly patients and sum up the therapy for elderly patients with calcified root canal in community hospital. Methods: 148 calcified root canals were selected form the age of 60-72 elderly patients. Under the EyeMag magnifying glass, low speed ball drill or ultrasonic instrument were used to remove the pulp chamber calcifications. Then C-Pilot files dipped into Glyde gel were used to unchoke root canals. While the condition of the root canal calcification and dredge effect were recorded during the operation. Finally root canal preparation, disinfection and filling were performed in sequence. Results:Calcified root canals of the elderly people were usually happened in maxillary first molar, anterior teeth, premolar and the success rate of molar dredge were 91.67%, 72.73%and 60.80%respectively, which showed that the dredge success rate of anterior teeth group was higher than molar group(χ2=4.02, P<0.05). 1/3 coronal segments of root canal and 1/3 middle segments of root canal were prone to calcify, whose dredge success rate was obviously higher than that of lower segment ( χ2=19.33, P<0.05). Conclusion:Regarding the treatment of the elderly patients’ calcified root canals, clinical dentists should be careful, patient and confident, using various treatment instruments and equipments flexibly and comprehensively, which could achieve favorable treatment results.%目的:观察老年人根管钙化情况,总结高校社区医院对老年患者钙化根管的治疗方法。方法:选择60-72岁老年患者的148个钙化根管,在EyeMag放大镜下,分别采用低速球钻或超声器械去除髓室内钙化物, C型先锋锉蘸取Glyde凝胶进行根管疏通,术中记录根管钙化情况和疏通效果,最后完成根管预备、消毒和充填。结果:老年人钙化根管多见于上颌第一磨牙,前牙、前磨牙、磨牙疏通成功率分别为:91.67%,72.73%

  8. Water quality of the Boca Raton canal system and effects of the Hillsboro Canal inflow, southeastern Florida, 1990-91

    Science.gov (United States)

    McKenzie, D.J.

    1995-01-01

    The City of Boca Raton in southeastern Palm Beach County, Florida, is an urban residential area that has sustained a constant population growth with subsequent increase in water use. The Boca Raton network of canals is controlled to provide for drainage of excess water, to maintain proper coastal ground-water levels to prevent saltwater intrusion, and to recharge the surficial aquifer system from which the city withdraws potable water. Most of the water supplied to the Boca Raton canal system and the surficial aquifer system, other than rainfall and runoff, is pumped from the Hillsboro Canal. The Biscayne aquifer, principal hydrogeologic unit of the surficial aquifer system, is highly permeable and there is a close relation between water levels in the canals and the aquifer. The amount of water supplied by seepage from the conservation areas is unknown. Because the Hillsboro Canal flows from Lake Okeechobee and Water Conservation Areas 1 and 2, which are places of more highly mineralized ground water and surface water, the canal is a possible source of contamination. Water samples were collected at 10 canal sites during wet and dry seasons and analyzed for major inorganic ions and related characteristics, nutrients, and trace elements. All concentrations were generally within or less than the drinking-water standards established by the Florida Department of Environmental Protection. The high concentrations of sodium and chloride that were detected in samples from the Boca Raton canal system are probably from the more mineralized water of the Hillsboro Canal. Other water-quality data, gathered from various sources from 1982 through 1991, did not indicate any significant changes nor trends. The effects of the Hillsboro Canal on the water quality of the Boca Raton canal system are indicated by increased concentrations of sodium, chloride, dissolved solids, and total organic carbon. Concentrations of the constituents in the canal water generally decrease with distance

  9. Anal cancer; Cancer du canal anal

    Energy Technology Data Exchange (ETDEWEB)

    Fesneau, M.; Champeaux-Orange, E. [Service de radiotherapie, Centre regional universitaire de cancerologie Henry-S.-Kaplan CHU de Tours, Hopital Bretonneau, 37 - Tours (France); Champeaux-Orange, E. [Service d' oncologie-radiotherapie, Centre hospitalier regional d' Orleans, 45 - Orleans (France); Hennequin, C. [Service de cancerologie-radiotherapie, hopital Saint-Louis, 75 - Paris (France)

    2010-07-01

    Anal canal epidermoid carcinomas represent 1.2% of digestive cancers and 6% of ano-rectal cancers. For localized diseases, the treatment is based on radiotherapy with or without chemotherapy (5-FU and cisplatin or mitomycin), according to tumour and nodal extension. The recommended treatment dose is 45 Gy in the anal canal, the mesorectum, para-rectal lymph nodes, and inguinal lymph nodes. An additional dose of 15 to 20 Gy is delivered in the initial tumour for good responders. Salvage surgery is necessary in case of poor response. The organs at risk to be considered are bladder, femur heads, small intestine and vulva. The objective of this work is to summarize the epidemiological and radio-anatomic and prognostic characteristics of this tumour. The conformal radiotherapy technique is illustrated by a case report. (authors)

  10. Ewing Sarcoma of the External Ear Canal.

    Science.gov (United States)

    Binnetoglu, Adem; Baglam, Tekin; Tokuc, Gulnur; Kecelioglu Binnetoglu, Kiymet; Gerin, Fatma; Sari, Murat

    2016-01-01

    Background. Ewing sarcoma (ES) is a high-grade malignant tumor that has skeletal and extraskeletal forms and consists of small round cells. In the head and neck region, reported localization of extraskeletal ES includes the larynx, thyroid gland, submandibular gland, nasal fossa, pharynx, skin, and parotid gland, but not the external ear canal. Methods. We present the unique case of a 2-year-old boy with extraskeletal ES arising from the external ear canal, mimicking auricular hematoma. Results. Surgery was performed and a VAC/IE (vincristine, adriamycin, cyclophosphamide alternating with ifosfamide, and etoposide) regimen was used for adjuvant chemotherapy for 12 months. Conclusion. The clinician should consider extraskeletal ES when diagnosing tumors localized in the head and neck region because it may be manifested by a nonspecific clinical picture mimicking common otorhinolaryngologic disorders. PMID:27313930

  11. Squamous cell carcinoma of the anal canal.

    LENUS (Irish Health Repository)

    Martin, F T

    2012-01-31

    Squamous cell carcinoma ofthe anal canal represents 1.5% of all malignancies affectingthe gastrointestinal tract. Over the past 20 years dramatic changes have been seen in both the epidemiological distribution of the disease and in the therapeutic modalities utilised to manage it. CLINICAL MANAGEMENT: Historically abdominoperineal resection had been the treatment of choice with local resection reserved for early stage disease. Work by Nigro et al. has revolutionised how we currently manage carcinoma of the anal canal, demonstrating combined modality chemoradiotherapy as an appropriate alternative to surgical resection with the benefit of preserving sphincter function. Surgery is then reserved for recurrent disease with salvage abdominoperineal resection. This article reviews current literature and highlights the changing therapeutic modalities with selected clinical cases

  12. Cancer of the external auditory canal

    DEFF Research Database (Denmark)

    Nyrop, Mette; Grøntved, Aksel

    2002-01-01

    . PATIENTS: Ten women and 10 men with previously untreated primary cancer. Median age at diagnosis was 67 years (range, 31-87 years). Survival data included 18 patients with at least 2 years of follow-up or recurrence. INTERVENTION: Local canal resection or partial temporal bone resection. MAIN OUTCOME......OBJECTIVE: To evaluate the outcome of surgery for cancer of the external auditory canal and relate this to the Pittsburgh staging system used both on squamous cell carcinoma and non-squamous cell carcinoma. DESIGN: Retrospective case series of all patients who had surgery between 1979 and 2000...... MEASURE: Recurrence rate. RESULTS: Half of the patients had squamous cell carcinoma. Thirteen of the patients had stage I tumor (65%), 2 had stage II (10%), 2 had stage III (10%), and 3 had stage IV tumor (15%). Twelve patients were cured. All patients with stage I or II cancers were cured except 1...

  13. The shape of the human lumbar vertebral canal A forma do canal vertebral lombar humano

    Directory of Open Access Journals (Sweden)

    Edmundo Zarzur

    1996-09-01

    Full Text Available Literature on the anatomy of the human vertebral column characterizes the shape of the lumbar vertebral canal as triangular. The purpose of the present study was to determine the precise shape of the lumbar vertebral canal. Ten lumbar vertebral columns of adult male cadavers were dissected. Two transverse sections were performed in the third lumbar vertebra. One section was performed at the level of the lower border of the ligamenta flava, and the other section was performed at the level of the pedicles. The shape of the lumbar vertebral canal at the level of the pedicles tends to be oval or circular, whereas the shape of the lumbar vertebral canal at the level of the lower border of the ligamenta flava is triangular. Thus, the shape of the human lumbar vertebral canal is not exclusively triangular, as reported in the literature. It is related to the level of the transversal section performed on the lumbar vertebra. This finding should be taken into consideration among factors involved in the spread of solutions introduced into the epidural space.A literatura sobre a anatomia da coluna vertebral descreve como sendo triangular o formato do canal vertebral na região lombar. O objetivo deste estudo é determinar a real forma do canal da coluna vertebral lombar.Dez colunas vertebrais de cadáveres de homens adultos foram dissecadas. Dois cortes transversais foram executados na terceira vértebra lombar. Um corte foi feito no nível das bordas inferiores de dois ligamentos amarelos vizinhos e o outro corte foi transversal, no nível dos pedículos. A forma do canal vertebral variou: no nível dos pedículos ela tende a ser oval ou circular e junto às bordas inferiores dos ligamentos amarelos passa a ser triangular. Portanto, a forma do canal vertebral lombar não é somente triangular; ela depende do nível em que se faz o corte transversal da vértebra. Estes achados devem ser levados em consideração entre os fatores envolvidos na difusão das

  14. Spinal canal narrowing during simulated frontal impact

    OpenAIRE

    Ivancic, Paul C.; Panjabi, Manohar M.; Tominaga, Yasuhiro; Pearson, Adam M.; Elena Gimenez, S.; Maak, Travis G.

    2005-01-01

    Between 23 and 70% of occupants involved in frontal impacts sustain cervical spine injuries, many with neurological involvement. It has been hypothesized that cervical spinal cord compression and injury may explain the variable neurological profile described by frontal impact victims. The goals of the present study, using a biofidelic whole cervical spine model with muscle force replication, were to quantify canal pinch diameter (CPD) narrowing during frontal impact and to evaluate the potent...

  15. Carotid canal dehiscence in the human skull

    Energy Technology Data Exchange (ETDEWEB)

    Pastor Vazquez, J.F.; Gil Verona, J.A. [Department of Anatomy, Faculty of Medicine, University of Valladolid, Ramon y Cajal, 7, E-47005 Valladolid (Spain); Garcia Porrero, M. [Department of Radiology, Faculty of Medicine, University of Valladolid (Spain)

    1999-06-01

    Abnormalities of the floor of the carotid canal have been studied in 538 skulls. These abnormalities range from a fissure to total absence of the floor. This variation may be caused by abnormalities of the internal carotid artery or deficiencies in ossification of the skull base. CT suggests that these changes should be taken into account by surgeons working on the skull base. (orig.) With 4 figs., 8 refs.

  16. Koebner phenomenon of the ear canal skin.

    LENUS (Irish Health Repository)

    Young, O

    2009-02-01

    The Koebner phenomenon originally described the appearance of psoriatic lesions in the uninvolved skin of patients with psoriasis as a consequence of trauma. We describe a case of concurrent lichen planus and sarcoidosis in the auditory canal, which represents an unusual manifestation of the Koebner phenomenon. This is the first case of concurrent lichen planus and sarcoidosis in the head and neck region and highlights the need for biopsy to allow accurate histopathological diagnosis and treatment.

  17. Root canal filling using Resilon: a review.

    LENUS (Irish Health Repository)

    Shanahan, D J

    2011-07-01

    Root canal treatment is achieved by chemo-mechanical debridement of the root canal system followed by filling. The filling material \\'entombs\\' residual bacteria and acts as a barrier which prevents the entrance of oral microorganisms and reinfection of the root canal system through microleakage. However, filling with contemporary root filling materials such as gutta-percha offers limited long-term resistance to microorganisms; as a result other materials such as Resilon have been investigated as alternatives. The aim of this review was to analyse the literature to consider whether Resilon is a suitable root canal filling material. A MEDLINE and Cochrane library search including various keyword searches identified several papers which investigated or discussed Resilon or RealSeal\\/Epiphany. Analysis of the literature demonstrated that the bulk of the literature is in vitro in nature, based largely on leakage-type studies, and demonstrates a wide variety of methodologies with conflicting findings; as a result meaningful conclusions are difficult. Within the limit of these in vitro studies Resilon appears to perform adequately in comparison to gutta-percha, however, as a result of the questionable merit of such studies, it cannot presently be considered an evidence-based alternative to the current gold standard gutta-percha. It is imperative that before Resilon is considered as a replacement material, a better understanding of the physical properties of the resin sealer and the reality of the adhesive \\'monoblock\\' are elucidated. The literature also demonstrates a paucity of quality long-term clinical outcome studies which will need to be addressed before firm conclusions can be reached.

  18. Fat herniation through the canal of Schwalbe.

    Science.gov (United States)

    Cesmebasi, A; Abel, N; Tubbs, R S; Loukas, M

    2014-11-01

    The authors report a case of fat herniation through the canal of Schwalbe noted in a female cadaver during abdominopelvic dissection. Perineal hernias are rare hernias, and herniations through the hiatus of Schwalbe represent a rare posterior lateral perineal hernia. While these hernias are extremely rare, anatomists and surgeons should be aware of them, and the clinical significance and manifestations which may occur with these hernias. PMID:25448911

  19. Koebner phenomenon of the ear canal skin.

    LENUS (Irish Health Repository)

    Young, O

    2012-02-01

    The Koebner phenomenon originally described the appearance of psoriatic lesions in the uninvolved skin of patients with psoriasis as a consequence of trauma. We describe a case of concurrent lichen planus and sarcoidosis in the auditory canal, which represents an unusual manifestation of the Koebner phenomenon. This is the first case of concurrent lichen planus and sarcoidosis in the head and neck region and highlights the need for biopsy to allow accurate histopathological diagnosis and treatment.

  20. Lesions in the external auditory canal

    Directory of Open Access Journals (Sweden)

    Priyank S Chatra

    2011-01-01

    Full Text Available The external auditory canal is an S- shaped osseo-cartilaginous structure that extends from the auricle to the tympanic membrane. Congenital, inflammatory, neoplastic, and traumatic lesions can affect the EAC. High-resolution CT is well suited for the evaluation of the temporal bone, which has a complex anatomy with multiple small structures. In this study, we describe the various lesions affecting the EAC.

  1. Comparison of Bacterial Leakage between 3 Different Root Canal Obturation Techniques in Oval Shaped Canals

    Directory of Open Access Journals (Sweden)

    Eshagh-ali Saberi

    2014-06-01

    Full Text Available Introduction: The purpose of this study was to evaluate the sealing ability of 3 obturation techniques in oval-shaped canals by bacterial leakage assessment. Methods: Sixty mandibular incisors with oval canals were selected after providing buccolingual and mesiodistal radiographs. The teeth were sectioned at a 10 mm distance from the apex. After instrumentation, the teeth were divided into 3 groups and the canals in the three groups were obturated with lateral condensation (G1, warm vertical condensation (G2 and thermoplasticized injectable gutta percha (G3. The teeth were exposed to human saliva. Observing the turbidity of the BHI broth for a period of 63 days the number of days required for the complete contamination of root canals was recorded. The data were analyzed using descriptive statistical methods and Kruskal-Wallis test with SPSS statistical software. Results: Warm vertical condensation (G2 needed a significantly greater average time for leakage than the two other methods. No significant differences were found between lateral condensations and thermoplasticized injectable G.P techniques. Conclusion: warm vertical condensation provides a better seal against bacterial leakage than lateral condensation and obtura II method in obturating oval-canals.

  2. ROOT CANAL IRRIGANTS AND IRRIGATION TECHNIQUES: A REVIEW

    Directory of Open Access Journals (Sweden)

    Aniketh

    2015-04-01

    Full Text Available Root canal irrigation is not much emphasised in endodontic therapy. Most articles discussed are on root canal shaping and obturation not much emphasis is given for irrigation. There are many irrigation solutions which are introduced into market. The primary objective of root canal therapy is the ret ention of the pulpless or pulpally involved tooth with its associated periapical tissues in a healthy state. Achievement of this objective requires that the pulpal spaces and contents be eliminated as sources of infection. As the Enterococcus faecalis is a lso found to be the most important cause for endodontic failures, the action and efficacy of fewer irrigants against E. faecalis should also be given prime importance as of others. Therefore, the introduction of an antimicrobial endodontic irrigant during root canal therapy should be given priority in the hierarchy of root canal treatment. The purpose of this article is to analyse root canal irrigants, irrigation techniques and irrigation protocol.

  3. Geophysical investigation of a dutch levee and canal using various seismic and GPR techniques

    NARCIS (Netherlands)

    Noorlandt, R.P.; Kleine, M.P.E. de; Kruiver, P.P.; Bakker, M.A.J.; Mesdag, C.S.; Hoogendoorn, R.M.

    2011-01-01

    A geophysical survey has been carried out on the Juliana Canal and levee in the south of the Netherlands. For a stretch of about 35 km along this canal various construction works are planned, to deepen and widen the canal. The canal is in a geological setting such that leakage from the canal to the

  4. Optimizing the chemical aspect of root canal irrigation

    OpenAIRE

    Wesselink, P.R.; Sluis, van der, J.; Versluis, A.M.; Macedo, de, R.G.

    2013-01-01

    Root canal treatment is aimed at the removal of inflamed and infected tissue present in the root canal system. It will prevent the entrance of new microorganisms or nutrients in order to maintain or create a healthy environment around the root. There is sufficient evidence that shows that traditional endodontic therapy cannot make the root canal system completely free of bacteria. Moreover, it may not always result in complete healing of apical periodontitis, highlighting the need of optimizi...

  5. Choice of root canal irrigants by Serbian dental practitioners

    OpenAIRE

    Tošić Goran; Miladinović Milan; Kovačević Milorad; Stojanović Miodrag

    2016-01-01

    Background/Aim. Root canal treatment is considered to be the one of the most important procedures in endodontic treatment. To irrigate the root canal it is most common to use sodium hypochlorite (NaOCl), chlorhexodine, ethylenediami-netetraacetic acid (EDTA), local anesthetic solution, while the most used in Serbia is hydrogen peroxide (H2O2). The aim of this survey was to reveal the preferred root canal irrigants used by general dental practitioners in Ser...

  6. ROOT CANAL IRRIGANTS AND IRRIGATION TECHNIQUES: A REVIEW

    OpenAIRE

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

    2015-01-01

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

  7. Interactions between root canal irrigants, sealers and dentin

    OpenAIRE

    Neelakantan, P.

    2016-01-01

    The objective of this thesis was to determine the interactions between root filling materials and root dentin and to investigate if root canal irrigating solutions had an impact on these interactions. The following outcomes were assessed in the studies encompassed in this thesis: (i) dislocation resistance of an epoxy resin based root canal sealer and tricalcium silicate based root canal sealers, (ii) the influence of irrigation protocols on the sealing ability and chemical interactions with ...

  8. Endodontic Considerations in Three-canalled Premolars: A Practical Update

    Science.gov (United States)

    Mohammadi, Zahed; Shalavi, Sousan; Giardino, Luciano; Asgary, Saeed

    2016-01-01

    The most difficult clinical considertions in orthograde root canal treatment are generally related to the anatomy of the teeth. Three-canalled maxillary and mandibular premolars (mini-molars) have been reported in several studies. The purpose of this paper was to review various aspects of three-canalled premolars including incidence, clinical and radiographic diagnosis, racial predisposition, access cavity preparation, instrumentation and obturation. PMID:27141223

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

    OpenAIRE

    Zhang, Ling; Chen, Hai-Bin; Wang, Yi; ZHANG Li-ying; Liu, Jing-cheng; WANG Zheng-guo

    2012-01-01

    【Abstract】Cervical spinal canal narrowing can lead to injury of the spinal cord and neurological symptoms in-cluding neck pain, headache, weakness and parasthesisas. According to previous and recent clinical researches, we investigated the geometric parameters of normal cervical spinal canal including the sagittal and transverse diameters as well as Torg ratio. The mean sagittal diameter of cervical spinal canal at C 1 to C 7 ranges from 15.33 mm to 20.46 mm, ...

  10. The Development of Culture Industry along Canal Cities and Strategy of Image Dissemination ---From the Perspective of Regional Operation between Huaian and Yangzhou%运河城市文化产业发展与形象传播战略——以淮安、扬州区域协同为视角

    Institute of Scientific and Technical Information of China (English)

    张沭宁

    2012-01-01

    文章提出京杭运河苏北段沿岸城市淮安、扬州开展区域文化、旅游产业协同发展战略,认为可以依托运河文化主题强化文化、旅游合作以及创意产业融合,开展产权共享、影视演艺、创意设计等多层次合作,构建“大文化、大旅游、大产业”业态和多样性文化旅游区,这对于传播运河沿岸城市的文化形象、合作打造运河文化品牌都有积极意义。%The author of this paper propounds that the cities such Huaian and Yangzhou along Great Canal (the nothern section of Jiangsu province) should employ the strategy of cooperating the regional culture and tourism industry, and suggest that, on the basis of canal culture, we should integrate culture, tourism cooperation and creative industry and carry out more cooperations about property sharing, film and performance and creative design, forming the pattern of "big culture, big tourism and big industry" and of diverse culture, which plays an important role in disseminating the cultural image of coastal cities along the Great Canal and creating the cultural brand about the canal

  11. Morphometric analysis of the cervical spinal canal on MRI.

    Science.gov (United States)

    Matveeva, Niki; Janevski, Petar; Nakeva, Natasha; Zhivadinovik, Julija; Dodevski, Ace

    2013-01-01

    Two useful numerical values, called the Torg ratio and the spinal canal diameter (SC diameter) are widely accepted as reliable morphometric determinants of spinal stenosis. The aims of the study were to examine morphometric determinants of the cervical spinal canal on MRI in both sexes and analyse them as reliable indicators of spinal stenosis. Measurements were made on 50 MR images (sagittal T2 weighted images from C3 to C7) of the cervical spine of patients from the Emergency Centre who had undertaken MRI of the cervical spine in addition to CT for various diagnostic indications. Torg ratio, used in evaluation of the spinal canal stenosis on plain x-ray radiographs, cannot be used as a spinal canal stenosis indicator due to the gender differences in the vertebral bodies' width. Sagittal canal diameters were more spread out in males than in females. MRI enables the value of the space available for the spinal cord, (SAC) to be determined, by subtracting the sagittal diameter of the spinal cord from the sagittal diameter of the spinal canal. Not gender, but individual and level differences in the SAC values were evident (cervical cord enlargement). SAC values relied more on the spinal canal than on the spinal cord, so that the differences in the dimensions of the spinal cord accounted for less variability in the SAC values. MR imaging of the cervical spine provides more accurate cervical canal and spinal cord measurements that could serve as morphometric determinants of the cervical canal stenosis. PMID:24280784

  12. [Canal infection. Ecological theory and repair with osteodentin].

    Science.gov (United States)

    Muñiz, M A; Zeberio, T

    1991-01-01

    The characteristics of the infection in the root canal are analyzed, specially its development before pulpal necrosis. It is inferred that it is an ecological infection with a function: to decompose the necrosis. Inactivating the infection in the canal by the formocresol technique, calcium hidroxide or with the conventional basic treatment in Endodontics, cleaning, washing, disinfecting and, in this case, with partial obturation of the canal, it is possible to induce a reparation with osteodentine that can cover all the free extension of the canal. PMID:1882104

  13. Imaging of carcinoma of the external auditory canal: a pictorial essay

    OpenAIRE

    Ong, Cheng K.; Pua, Uei; Chong, Vincent F.H.

    2008-01-01

    Abstract Carcinoma of the external auditory canal presents a challenge in management, largely due to limited experience in treating this rare disease and the lack of a universally accepted staging system. Prognosis is most dependent on the extent of local disease at presentation, while resection margin status is also a strong determinant of survival in post-operative patients. The intent of this pictorial essay is to review the pattern of tumour spread and highlight the value of imaging, part...

  14. Analysis of gutta-percha’s root canal filling capacity through three different obturation techniques

    OpenAIRE

    Cláudio Maniglia-Ferreira; Fábio de Almeida-Gomes; Nadine Luísa Soares de Lima Guimarães; Tatyana Albuquerque Ximenes; Natália Siqueira Campos Pontes Canuto

    2011-01-01

    Introduction and objective: The aim of this study was to determine gutta-percha’s root canal filling capacity through three different filling techniques. Material and methods: Sixty single-rooted human teeth were cleaned, shaped and randomly divided according to the filling technique: Group I: Lateral condensation; Group II: Hydraulic compression; Group III: Tagger’s hybrid. All procedures were performed by two previously calibrated operators. The teeth were transversely sectioned into four c...

  15. Comparison of antimicrobial substantivity of root canal irrigants in instrumented root canals up to 72 h: An in vitro study

    OpenAIRE

    M N Shahani; Subba Reddy, V. V.

    2011-01-01

    Disinfection of the root canal system is one of the primary aims of root canal treatment. This can be achieved through the use of various antimicrobial agents in the form of irrigants and medicaments. The antimicrobial substantivity of 2% chlorhexidine gluconate, 1% povidone iodine, 2.5% hydrogen peroxide followed by 2% sodium hypochlorite, and 2% sodium hypochlorite alone as irrigants was assessed in instrumented root canals. 2% chlorhexidine showed antimicrobial substantivity lasting up to ...

  16. Analysis of gutta-percha’s root canal filling capacity through three different obturation techniques

    Directory of Open Access Journals (Sweden)

    Cláudio Maniglia-Ferreira

    2011-01-01

    Full Text Available Introduction and objective: The aim of this study was to determine gutta-percha’s root canal filling capacity through three different filling techniques. Material and methods: Sixty single-rooted human teeth were cleaned, shaped and randomly divided according to the filling technique: Group I: Lateral condensation; Group II: Hydraulic compression; Group III: Tagger’s hybrid. All procedures were performed by two previously calibrated operators. The teeth were transversely sectioned into four cuts, starting from the root apex (at 3 mm, 6 mm, 9 mm, and 12 mm, by using an Isomet diamond blade (wafering blade, series 15 high concentration, 5 inch blade, Buehler Ltd., Lake Bluff, IL, USA, mounted in an IsoMet® Low Speed Saw (Buehler Ltd., Lake Bluff, IL, USA, and water as a cooling medium. Each group’s cut was embedded in acrylic resin and polished. Root canal images were captured and then analysed by Image Tool 3.0 software (Department of Dental Diagnostic Science, University of Texas, Health Science Center, San Antonio, Texas. Measurements of root canal overall area and gutta-percha-filled area were executed,therefore, obtaining the percentage of gutta-percha’s root canal filling capacity for each slice. Results: Data were analyzed by GMC software 10.0 and Kruskal-Wallis test. Tagger’s hybrid technique (95.1% was superior to the other two techniques, followed by Hydraulic compression (89.1% and lateral condensation (70.6%. The results were statistically different among the three techniques, for all cuts (p 0.05. Conclusion: These results suggest that Tagger’s hybrid technique may yield better root canal filling capacity than Hydraulic compression and lateral condensation technique, which showed the worst filling capacity of all the three techniques employed.

  17. Revestimientos especiales para diques y canales

    Directory of Open Access Journals (Sweden)

    Zorzi, Silvano

    1964-11-01

    Full Text Available This paper summarizes the possibilities and advantages of adopting special facings for dykes and canals, and generally for all large hydraulic works, where waterproofing is of paramount importance. Technical advances in recent years have made it possible to prefabricate many facing units used in these types of works; large slabs, made in reinforced and prestressed concrete, are flexible, and watertight. Although there are many possibilities and types of facing treatments, the one described here is outstanding. It consists of narrow slabs, highly flexible, placed transversally with respect to the canal axis. They are attached with cement mortar, and the joints are finally sealed with a special mortar, called «Emboco». In this article a description is also given of a series of projects, where facing treatments have been used, which are now successfully in service. Finally some general and simple advise is given on the best procedure to apply these facing treatments in the most effective and economic manner.En este trabajo se resumen las posibilidades y ventajas que ofrecen los revestimientos especiales de diques y taludes de canales y, en general, en todas las grandes obras hidráulicas, en que la impermeabilización es de mayor importancia al tratar de conservar los caudales iniciales o la retención de aguas embalsadas, según los casos. Los progresos de las técnicas modernas, en particular la prefabricación, han permitido este tipo de revestimientos con losas de gran longitud, extremadamente flexibles e impermeables, de hormigón armado y pretensado. Aunque son muchas las posibilidades y tipos de revestimiento, destaca el que a continuación se expone: consiste en placas o losas estrechas, de gran flexibilidad, colocadas transversalmente al eje del canal sobre tongadas de mortero de cemento, y cuyas juntas se sellan, finalmente, con un mortero especial llamado «Emboco». Complementan la exposición teórica del método una serie de

  18. CAVERNOUS HEMANGIOMA OF THE INTERNAL AUDITORY CANAL

    Directory of Open Access Journals (Sweden)

    Mohammad Hossein Hekmatara

    1993-06-01

    Full Text Available Cavernous hemangioma is a rare benign tumor of the internal auditory canal (IAC of which fourteen cases have been reported so far."nTinnitus and progressive sensorineural hearing loss (SNHL are the chief complaints of the patients. Audiological and radiological planes, CTScan, and magnetic resonance image (MRI studies are helpful in diagnosis. The only choice of treatment is surgery with elective transmastoid trans¬labyrinthine approach. And if tumor is very large, the method of choice will be retrosigmoid approach.

  19. Cancer incidence in the Love Canal area.

    Science.gov (United States)

    Janerich, D T; Burnett, W S; Feck, G; Hoff, M; Nasca, P; Polednak, A P; Greenwald, P; Vianna, N

    1981-06-19

    Data from the New York Cancer Registry show no evidence for higher cancer rates associated with residence near the Love Canal toxic waste burial site in comparison with the entire state outside of New York City. Rates of liver cancer, lymphoma, and leukemia, which were selected for special attention, were not consistently elevated. Among the other cancers studied, a higher rate was noted only for respiratory cancer, but it was not consistent across age groups and appeared to be related to a high rate for the entire city of Niagara Falls. There was no evidence that the lung cancer rate was associated with the toxic wastes buried at the dump site.

  20. Water Environment Evolution along the China Grand Canal

    International Nuclear Information System (INIS)

    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

  1. Water Environment Evolution along the China Grand Canal

    Science.gov (United States)

    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

  2. Root canal treatment of mandibular second premolar tooth with taurodontism

    Directory of Open Access Journals (Sweden)

    Vujašković Mirjana

    2008-01-01

    Full Text Available INTRODUCTION 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. CASE OUTLINE 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. CONCLUSION 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.

  3. Root canal filling evaluation using optical coherence tomography

    Science.gov (United States)

    Negrutiu, Meda L.; Sinescu, Cosmin; Topala, Florin; Nica, Luminita; Ionita, Ciprian; Marcauteanu, Corina; Goguta, Luciana; Bradu, Adrian; Dobre, George; Rominu, Mihai; Podoleanu, Adrian Gh.

    2010-04-01

    Endodontic therapy consists in cleaning and shaping the root canal system, removing organic debris and sealing the intra-canal space with permanent filling materials. The purpose of this study was to evaluate various root canal fillings in order to detect material defects, the marginal adaptation at the root canal walls and to assess the quality of the apical sealing. 21 extracted single-root canal human teeth were selected for this study. We instrumented all roots using NiTi rotary instruments. All canals were enlarged with a 6% taper size 30 GT instrument, 0,5 mm from the anatomical apex. The root canals were irrigated with 5% sodium hypochlorite, followed by 17% ethylenediaminetetraacetic acid (EDTA). After the instrumentation was completed, the root canals were obturated using a thermoplasticizable polymer of polyesters. In order to assess the defects inside the filling material and the marginal fit to the root canal walls, the conebeam micro-computed tomography (CBμCT) was used first. After the CBμCT investigation, time domain optical coherence tomography working in en face mode (TDefOCT) was employed to evaluate the previous samples. The TDefOCT system was working at 1300 nm and was doubled by a confocal channel at 970 nm. The results obtained by CBμCT revealed no visible defects inside the root-canal fillings and at the interfaces with the root-canal walls. TDefOCT investigations permit to visualize a more complex stratificated structure at the interface filling material/dental hard tissue and in the apical region.

  4. Comprehensive work plan for Building 3001 storage canal at the Oak Ridge National Laboratory, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-01-01

    This Comprehensive Work Plan describes the method of accomplishment to replace the shielding protection of the water in the canal with a controlled low strength material (CLSM) 4. The canal was used during the operation of the Oak Ridge Graphite Reactor in the 1940s and 1950s to transport spent fuel slugs and irradiated test materials from the reactor, under water to the hot cell in Building 3019 for further processing, packaging, and handling. After the reactor was shut down, the canal was used until 1990 to store some irradiated materials until they could be transferred to a Solid Waste Storage Area. This task has the following objectives and components: (1) minimize potential future risk to human health and the environment; (2) reduce surveillance and maintenance cost of the canal; (3) perform site preparation activities; (4) replace the water in the canal with a solid CLSM; (5) pump the water to the Process Waste Treatment System (PWTS) for further processing at the same rate that the CLSM is pumped under the water; (6) remove the water using a process that will protect the workers and the public in the visitors area from contamination while the CLSM is being pumped underneath the water; (7) painting a protective coating material over the CLSM after the CLSM has cured.

  5. Closure of a unique mixed waste storage canal at the Dept. of Energy's Oak Ridge National Laboratory (ORNL)

    International Nuclear Information System (INIS)

    At the Department of Energy's (DOE's) Oak Ridge National Laboratory (ORNL) a unique closure was accomplished for a storage canal that contained both hazardous chemical contaminants controlled by the Resource Conservation and Recovery Act (RCRA), and radioactive contaminants controlled by the Atomic Energy Act (AEA). During 1991 and 1992, after approvals were received from the DOE and the Tennessee Department of Environment and Conservation (TDEC), subcontractors to DOE's Construction Manager were mobilized and remote controlled equipment was operated on site to remove the RCRA and radioactive contamination (referred to hereafter as mixed wastes) from the 3001 Storage Canal at ORNL. After numerous open-quotes surprisesclose quotes during the removal activities, each requiring problem resolution and approvals from DOE and TDEC, the canal closure was completed in September 1992 and final closure certification was submitted to TDEC in October 1992. The following discussion describes the learning experiences that ORNL and DOE acquired from a RCRA closure project for a mixed waste storage canal containing high radiation levels. The project was successful, especially since worker exposures were minimized, but was lengthy, requiring 30 months from notification of a leak in the canal until final demobilization of the subcontractor, and expensive to complete (total overall cost of $3 million)

  6. Management of mandibular first molar with four canals in mesial root

    OpenAIRE

    Subbiya, Arunajatesan; Kumar, Krishnamurthy Sathish; Vivekanandhan, Paramasivam; Prakash, Venkatachalam

    2013-01-01

    Successful root canal treatment depends on adequate cleaning, shaping, and filling of the root canal system. The presence of middle mesial (MM) root canal of mandibular molars has been reported by various authors. But incidence of four canals in mesial root of mandibular molar is very rare. The aim of this case report is to present and describe the identification and management of a mandibular first molar with four canals in the mesial root and single canal in the distal root.

  7. New Technologies to Improve Root Canal Disinfection.

    Science.gov (United States)

    Plotino, Gianluca; Cortese, Teresa; Grande, Nicola M; Leonardi, Denise P; Di Giorgio, Gianni; Testarelli, Luca; Gambarini, Gianluca

    2016-01-01

    Effective irrigant delivery and agitation are prerequisites to promote root canal disinfection and debris removal and improve successful endodontic treatment. This paper presents an overview of the currently available technologies to improve the cleaning of the endodontic space and their debridement efficacy. A PubMed electronic search was conducted with appropriate key words to identify the relevant literature on this topic. After retrieving the full-text articles, all the articles were reviewed and the most appropriate were included in this review. Several different systems of mechanical activation of irrigants to improve endodontic disinfection were analysed: manual agitation with gutta-percha cones, endodontic instruments or special brushes, vibrating systems activated by low-speed hand-pieces or by sonic or subsonic energy, use of ultrasonic or laser energy to mechanically activate the irrigants and apical negative pressure irrigation systems. Furthermore, this review aims to describe systems designed to improve the intracanal bacterial decontamination by a specific chemical action, such as ozone, direct laser action or light-activated disinfection. The ultrasonic activation of root canal irrigants and of sodium hypochlorite in particular still remains the gold standard to which all other systems of mechanical agitation analyzed in this article were compared. From this overview, it is evident that the use of different irrigation systems can provide several advantages in the clinical endodontic outcome and that integration of new technologies, coupled with enhanced techniques and materials, may help everyday clinical practice. PMID:27007337

  8. Visibility of the central canal on MRI

    Energy Technology Data Exchange (ETDEWEB)

    Petit-Lacour, M.C.; Lasjaunias, P.; Iffenecker, C.; Benoudiba, F.; Hadj Rabia, M.; Doyon, D. [Service de Neuroradiologie, Faculte de Paris Sud (France); Hurth, M. [Department of Neurosurgery, Faculte Paris Sud, Kremlin-Bicetre (France)

    2000-10-01

    The central canal of the spinal cord is present at birth and becomes progressively obliterated. Cadaver studies have shown that it may persiste partially or completely. To our knowledge, this entity has not been described on MRI. We reviewed 794 MRI studies of the spinal cord, and found 12 patients (aged 14 to 65 years) who had an intramedullary cavity. The cavity was at the junction of the ventral {sup 1}/{sub 3} and dorsal {sup 2}/{sub 3} of the spinal cord, except at the level of the lumbar enlargement, where it was central. It was filiform in most cases, although sometimes fusiform (3 to 4 mm in diameter), and had regular contours. The cavity were thoracic in 69 % of cases. The clinical features were totally unrelated to the image, and there were no anatomical factors (Chiari malformation, dysraphism) predisposing to syringomyelia. The images were perfectly compatible with a persistent central canal, which we interpret as a variant of normal anatomy. Therefore it is important to regard these findings as normal, to avoid unnecessary treatment and follow-up. (orig.)

  9. Optimizing the chemical aspect of root canal irrigation

    NARCIS (Netherlands)

    R.G. de Macedo

    2013-01-01

    Root canal treatment is aimed at the removal of inflamed and infected tissue present in the root canal system. It will prevent the entrance of new microorganisms or nutrients in order to maintain or create a healthy environment around the root. There is sufficient evidence that shows that traditiona

  10. 5 CFR 550.714 - Panama Canal Commission employees.

    Science.gov (United States)

    2010-01-01

    ...) Notwithstanding any other provisions of this subpart, an employee separated from employment with the Panama Canal... a position that meets all the following conditions: (1) The position is with the Panamanian public... below the employee's rate of basic pay as a Panama Canal Commission employee; (3) The position is...

  11. Reform in Indian canal irrigation: does technology matter?

    NARCIS (Netherlands)

    Narain, V.

    2008-01-01

    This paper examines the implications of technology - the design of canal irrigation for irrigation management reform. With reference to two different design systems in Indian irrigation - shejpali and warabandi - it shows that the potential for reform varies with the design of canal irrigation. Thre

  12. RCRA closure of the Building 3001 Storage Canal

    International Nuclear Information System (INIS)

    The 3001 Storage Canal is located under portions of Buildings 3001 and 3019 at Oak Ridge National Laboratory (ORNL) and has a capacity of approximately 62,000 gallons of water. The term canal has historically been used to identify this structure, however, the canal is an in-ground reinforced concrete structure satisfying the regulatory definition of a tank. From 1943 through 1963, the canal in Building 3001 was designed to be an integral part of the system for handling irradiated fuel from the Oak Ridge Graphite Reactor. Because one of the main initial purposes of the reactor was to produce plutonium for the chemical processing pilot plant in Building 3019, the canal was designed to be the connecting link between the reactor and the pilot plant. During the war years, natural uranium slugs were irradiated in the reactor and then pushed out of the graphite matrix into the system of diversion plates and chutes which directed the fuel into the deep pit of the canal. After shutdown of the reactor, the canal was no longer needed for its designed purpose. Since 1964, the canal has only been used to store radioisotopes and irradiated samples under a water pool for radiation protection. This report describes closure alternatives

  13. The Influence of Canalization on the Robustness of Boolean Networks

    CERN Document Server

    Kadelka, Claus; Laubenbacher, Reinhard

    2016-01-01

    Time- and state-discrete dynamical systems are frequently used to model molecular networks. This paper provides a collection of mathematical and computational tools for the study of robustness in Boolean network models. The focus is on networks governed by $k$-canalizing functions, a recently introduced class of Boolean functions that contains the well-studied class of nested canalizing functions. The activities and sensitivity of a function quantify the impact of input changes on the function output. This paper generalizes the latter concept to $c$-sensitivity and provides formulas for the activities and $c$-sensitivity of general $k$-canalizing functions as well as canalizing functions with more precisely defined structure. A popular measure for the robustness of a network, the Derrida value, can be expressed as a weighted sum of the $c$-sensitivities of the governing canalizing functions, and can also be calculated for a stochastic extension of Boolean networks. These findings provide a computationally eff...

  14. VARIATION OF MAXILLARY FIRST PREMOLAR WITH THREE ROOT CANALS

    Directory of Open Access Journals (Sweden)

    Janet Kirilova

    2014-09-01

    Full Text Available Background: Successful endodontic treatment requires effective biomechanical preparation of the root canals and three-dimensional obturation of the root canal system. This can be achieved only by knowing and identifying the variations in the root canal system of the endodontically treated teeth. The Aim: The aim of this article is to present cases of endodontic treatment of maxillary first premolar with three root canals – different types. Material and Methods: Five clinical cases of successful endodontic treatment of patients with maxillary first premolar and three root canals are described. Result and Discussion: It is noted that good endodontic practice requires good knowledge of dental anatomy and possible variations, accurate X-ray images, as well as use of magnifying equipment. Conclusion: Knowledge of dental anatomy is fundamental for good endodontic practice.

  15. Apical pressures developed by needles for canal irrigation.

    Science.gov (United States)

    Bradford, C E; Eleazer, P D; Downs, K E; Scheetz, J P

    2002-04-01

    Drying instrumented canals with pressurized air may result in patient morbidity or even fatality. Low pressure and side vent needles have been suggested to lessen the danger. This study observed apical pressures from different needles inserted deeply into small round and ovoid canals as instrumentation progressed. Low-pressure (5 psi) air was injected through the needles, and apical pressures were recorded after each instrument. Pressures varied greatly within each test group. Generalities that can be drawn are that binding the needle within the canal gives higher pressures than with the needle slightly short of binding and that pressures were higher with apexes instrumented to size 30 and higher. With the needle tightly bound, neither needle size, needle design, nor canal shape resulted in statistically significant mean pressure differences. With the needle slightly withdrawn, larger bore needles gave higher pressures than small diameter needles. Caution is advised with the clinical use of pressurized air in the drying of root canals. PMID:12043877

  16. One-stage neonatal corrective repair for d-transposition of the great arteries and complete atrio-ventricular canal.

    Science.gov (United States)

    Bautista-Hernandez, Victor; Marx, Gerald R; del Nido, Pedro J

    2007-01-01

    Association of d-transposition of the great arteries and complete atrio-ventricular canal constitutes an uncommon and complex cardiac anomaly usually associated with poor prognosis. We report our experience on one-stage neonatal repair for d-transposition of the great arteries and complete atrio-ventricular canal. Between August 1997 and 2005, four patients (two males and two females) underwent anatomical correction for d-transposition of the great arteries and complete atrio-ventricular canal using an arterial switch procedure and two-patch repair. Mean age and weight at operation were 20 days (range from 3 to 28 days) and 3.2kg (range from 2.7 to 3.5kg), respectively. None of the patients received preoperative palliative procedure. Associated lesions were left outflow tract obstruction in three patients and multiple muscular ventricular septal defects in two patients. All four patients survived the operation. There was one in-hospitality death due to fungal sepsis. One patient required late re-operation for left ventricular outflow tract obstruction and left atrio-ventricular valve regurgitation. For a mean follow-up of 67 months (range from 51 to 90 months) all patients are asymptomatic and with no residual defects. Corrective repair of d-transposition of the great arteries and complete atrio-ventricular canal can be successfully achieved in this very challenging population during the neonatal period. PMID:17110123

  17. Failure to obtain adequate anaesthesia associated with a bifid mandibular canal: a case report.

    Science.gov (United States)

    Lew, K; Townsen, G

    2006-03-01

    The inferior alveolar nerve (IAN) block is the most common method for obtaining mandibular anaesthesia in dental practice but it is estimated to have a success rate of only 80 to 85 per cent. Causes of failure include problems with operator technique and anatomical variation between individuals. This case report involves a patient who received IAN blocks on two separate occasions that resulted in only partial anaesthesia of the ipsilateral side of the mandible. Radiographic assessment disclosed the presence of bifid mandibular canals that were present bilaterally and that may have affected the outcomes of the local anaesthetic procedures. Previous studies of bifid mandibular canals are reviewed and suggestions provided that should enable clinicians to differentially diagnose, and then manage, cases where IAN blocks result in inadequate mandibular anaesthesia. PMID:16669483

  18. Surgical Procedures for External Auditory Canal Carcinoma and the Preservation of Postoperative Hearing

    Directory of Open Access Journals (Sweden)

    Hiroshi Hoshikawa

    2012-01-01

    Full Text Available Carcinoma of the external auditory canal (EAC is an unusual head and neck malignancy. The pathophysiology of these tumors is different from other skin lesions because of their anatomical and functional characteristics. Early-stage carcinoma of the EAC can be generally cured by surgical treatment, and reconstruction of the EAC with a tympanoplasty can help to retain hearing, thus improving the patients’ quality of life. In this study, we present two cases of early-stage carcinoma of the EAC treated by canal reconstruction using skin grafts after lateral temporal bone resection. A rolled-up skin graft with a temporal muscle flap was useful for keeping the form and maintaining the postoperative hearing. An adequate size of the skin graft and blood supply to the graft bed are important for achieving a successful operation.

  19. Efficacy of ultrasound-guided adductor canal block for postoperative analgesia in pediatric patients undergoing knee operation%超声引导收肌管阻滞用于患儿膝关节术后镇痛的效果

    Institute of Scientific and Technical Information of China (English)

    孙可; 金梅; 袁亮婧; 杨庆国

    2016-01-01

    Objective To investigate the efficacy of adductor canal block (ACB) under the guidance of ultrasound for postoperative analgesia in the pediatric patients undergoing knee operation.Methods Sixty pediatric patients,aged 3-12 yr,of American Society of Anesthesiologists physical status Ⅰ or Ⅱ,weighing 12-35 kg,scheduled for elective unilateral knee operation,were selected and randomly divided into 2 equal groups using a random number table:ultrasound-guided ACB group (group ACB) and ultrasound-guided femoral nerve block (FNB) group (group FNB).After induction of general anesthesia,ACB or FNB was performed under the guidance of ultrasound,and 0.3% ropivacaine 1 ml/kg was injected.Anesthesia was maintained with intravenous infusion of remifentanil combined with propofol,and bispectral index value was maintained at 40-60.Immediately after injection of local anesthetics (T0),and at 4,8,12 and 24 h after injection (T1-4),analgesic efficacy was assessed using the FLACC pain scale,and quadriceps strength was assessed by manual muscle testing.Satisfactory analgesia was defined as FLACC score ≤ 3,and obvious quadriceps weakness was defined as manual muscle testing grade 0-2.The complications associated with nerve block (such as local anesthetic toxicity,bleeding at the puncture site,hematoma),and occurrence of postoperative nausea and vomiting and delayed emergence were recorded.Results There was no significant difference between two groups in the rate of satisfactory analgesia at T1-T4 (P> 0.05).Compared with group FNB,the incidence of obvious quadriceps weakness was significantly lower at T1-T3 (P<0.05),and no significant change was found at T4 in group ACB (P>0.05).There was no significant difference in the incidence of nausea or retching between two groups (P>0.05).Complications associated with nerve block,vomiting and delayed emergence were not observed in the two groups.Conclusion Ultrasound-guided ACB can be safely and effectively used for postoperative

  20. Imaging of carcinoma of the external auditory canal: a pictorial essay

    Science.gov (United States)

    Ong, Cheng K.; Pua, Uei

    2008-01-01

    Abstract Carcinoma of the external auditory canal presents a challenge in management, largely due to limited experience in treating this rare disease and the lack of a universally accepted staging system. Prognosis is most dependent on the extent of local disease at presentation, while resection margin status is also a strong determinant of survival in post-operative patients. The intent of this pictorial essay is to review the pattern of tumour spread and highlight the value of imaging, particularly magnetic resonance imaging in pre-operative tumour mapping. PMID:18940738

  1. Reduction of Enterococcus faecalis in curved root canals after various sizes and tapers of canal preparation

    Directory of Open Access Journals (Sweden)

    Amir Abbas Moshari

    2015-01-01

    Full Text Available Aims: The aim of this study was to evaluate the reduction of Enterococcus faecalis in curved root canals after various sizes and tapers of the canal preparation. Materials and Methods: Mandibular first molars (n = 103 with curved mesiobuccal canals were divided into one control (n = 5 and 7 experimental (n = 14 groups, were inoculated with E. faecalis (ATTC 29212 and prepared with the following RaCe files (FKG Dentaire as master apical file: Groups: 25.04, 25.06, 30.04, 30.06, 35.04, 35.06 and 40.06. All the experimental groups were irrigated with 2 mL of 1% sodium hypochlorite during instrumentation and finally rinsed with 17% ethylenediaminetetraacetic acid (EDTA (2 mL followed by 5.25% NaOCl (2 mL and sterile distilled water. Colony counting was performed after incubation. Statistical Analysis Used: Resulting data were analyzed using one-way ANOVA and Tukey′s post-hoc test, (P < 0.05. Results and Conclusions: All the experimental groups showed significant bacterial reduction (P < 0.001. Although the greater the size/taper or both led to more decreased amount of bacteria, differences between the groups with the identical size and different tapers, and among the groups with the same taper and different sizes were not significant. Based on this study, 25.04 along with using 2 mL of 1% NaOCl during instrumentation, and using 17% EDTA and 5.25% NaOCl as final rinse successively after the termination of preparation, can effectively reduce intra-canal bacteria and preserve root structure.

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

    Directory of Open Access Journals (Sweden)

    Sushma Rathi

    2010-01-01

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

  3. Spinal canal surrogate for testing intradural implants.

    Science.gov (United States)

    Oya, H; Howard, M A; Shurig, R; Gillies, G T

    2012-11-01

    We have designed, built and tested an anthropomorphic-scale surrogate spinal canal, for use in preliminary evaluations of the performance characteristics of a novel intradural spinal cord stimulator. The surrogate employs a silicone mock spinal cord with semi-major and semi-minor diameters of 10 and 6 mm, respectively, commensurate with those of actual thoracic-level spinal cord. The axial restoring force provided by the 300 µm thick silicone denticulate ligament constructs on the mock cord is ~ 0.32 N mm(-1) over a 1.5 mm range of displacement, which is within a factor of 2 of that measured by others in human cadaver specimens. Examples of testing protocols of prototype intradural stimulators that employ this device are discussed. PMID:22953718

  4. Alternative techniques in root canal debridement

    Science.gov (United States)

    Luca, Ruxandra; Todea, Carmen; Bǎlǎbuc, Cosmin; Nica, Luminita; Armani, Giacomo; Locovei, Cosmin

    2014-01-01

    Studies have demonstrated that conventional chemo-mechanical preparation is limited regarding the decontamination of the endodontic space, which is why alternative techniques such as laser radiation have their importance in the modern endodontic treatment. The present study aims to assess the possibility of improving the debridement of the root canals by removing smear layer using Er: YAG laser radiation. We used 18 extracted teeth, which were subjected to the same initial protocol and then divided into 5 study groups: the control group has not been treated with laser; the other 4 groups were exposed to laser radiation using two different geometries peaks of quartz and two energy levels. Scanning electronic microscopy revealed an increased efficiency in the debridement of all interested areas when using PIPS and XPulse tips at proper energy. In the two groups treated with inferior laser energy, the debridement didn't prove to be superior to the conventional treatment.

  5. Traumatic facial nerve palsy: CT patterns of facial nerve canal fracture and correlation with clinical severity

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Jae Cheol; Kim, Sang Joon; Park, Hyun Min; Lee, Young Suk; Lee, Jee Young [College of Medicine, Dankook Univ., Chonan (Korea, Republic of)

    2002-07-01

    To analyse the patterns of facial nerve canal injury seen at temporal bone computed tomography (CT) in patients with traumatic facial nerve palsy and to correlate these with clinical manifestations and outcome. Thirty cases of temporal bone CT in 29 patients with traumatic facial nerve palsy were analyzed with regard to the patterns of facial nerve canal involvement. The patterns were correlated with clinical grade, the electroneurographic (ENoG) findings, and clinical outcome. For clinical grading, the House-Brackmann scale was used, as follows:grade I-IV, partial palsy group; grade V-VI, complete palsy group. The electroneuronographic findings were categorized as mild to moderate (below 90%) or severe (90% and over) degeneration. In 25 cases, the bony wall of the facial nerve canals was involved directly (direct finding): discontinuity of the bony wall was onted in 22 cases, bony spicules in ten, and bony wall displacement in five. Indirect findings were canal widening in nine cases and adjacent bone fracture in two. In one case, there were no direct or indirect findings. All cases in which there was complete palsy (n=8) showed one or more direct findings including spicules in six, while in the incomplete palsy group (n=22), 17 cases showed direct findings. In the severe degeneration group (n=13), on ENog, 12 cases demonstrated direct findings, including spicules in nine cases. In 24 patients, symptoms of facial palsy showed improvement at follow up evaluation. Four of the five patients in whom symptoms did not improve had spicules. Among ten patients with spicules, five underwent surgery and symptoms improved in four of these; among the five patients not operated on , symptoms did not improve in three. In most patients with facial palsy after temporal bone injury, temporal bone CT revealed direct or indirect facial nerve canal involvement, and in complete palsy or severe degeneration groups, there were direct findings in most cases. We believe that meticulous

  6. Laser scanning dental probe for endodontic root canal treatment

    Science.gov (United States)

    Blank, Molly A. B.; Friedrich, Michal; Hamilton, Jeffrey D.; Lee, Peggy; Berg, Joel; Seibel, Eric J.

    2011-03-01

    Complications that arise during endodontic procedures pose serious threats to the long-term integrity and health of the tooth. Potential complexities of root canals include residual pulpal tissue, cracks, mesial-buccal 2 and accessory canals. In the case of a failed root canal, a successful apicoectomy can be jeopardized by isthmuses, accessory canals, and root microfracture. Confirming diagnosis using a small imaging probe would allow proper treatment and prevent retreatment of endodontic procedures. An ultrathin and flexible laser scanning endoscope of 1.2 to 1.6mm outer diameter was used in vitro to image extracted teeth with varied root configurations. Teeth were opened using a conventional bur and high speed drill. Imaging within the opened access cavity clarified the location of the roots where canal filing would initiate. Although radiographs are commonly used to determine the root canal size, position, and shape, the limited 2D image perspective leaves ambiguity that could be clarified if used in conjunction with a direct visual imaging tool. Direct visualization may avoid difficulties in locating the root canal and reduce the number of radiographs needed. A transillumination imaging device with the separated illumination and light collection functions rendered cracks visible in the prepared teeth that were otherwise indiscernible using reflected visible light. Our work demonstrates that a small diameter endoscope with high spatial resolution may significantly increase the efficiency and success of endodontic procedures.

  7. Discharge Estimation in a Lined Canal Using Information Entropy

    Directory of Open Access Journals (Sweden)

    Yen-Chang Chen

    2014-03-01

    Full Text Available This study applies a new method and technology to measure the discharge in a lined canal in Taiwan. An Acoustic Digital Current Meter mounted on a measurement platform is used to measure the velocities over the full cross-section for establishing the measurement method. The proposed method primarily employs Chiu’s Equation which is based on entropy to establish a constant ratio the relation between the maximum and mean velocities in an irrigation canal, and compute the maximum velocity by the observed velocity profile. In consequence, the mean velocity of the lined canal can be rapidly determined by the maximum velocity and the constant ratio. The cross-sectional area of the artificial irrigation canal can be calculated for the water stage. Finally, the discharge in the lined canal can be efficiently determined by the estimated mean velocity and the cross-sectional area. Using the data of discharges and stages collected in the Wan-Dan Canal, the correlation of stage and discharge is also developed for remote real-time monitoring and estimating discharge from the pumping station. Overall, Chiu’s Equation is demonstrated to reliably and accurately measure discharge in a lined canal, and can serve as reference for future calibration for a stage-discharge rating curve.

  8. Bacterial coronal leakage after obturation with three root canal sealers.

    Science.gov (United States)

    Timpawat, S; Amornchat, C; Trisuwan, W R

    2001-01-01

    The purpose of this study was to compare the bacterial leakage of root canals obturated with three root canal sealers, using Endodontalis faecalis as a microbial tracer to determine the length of time for bacteria to penetrate through the obturated root canal to the root apex. Seventy-five, single-rooted teeth with straight root canals had the crown cut off at the cementoenamel junction. Root canals were instrumented by a step-back technique. The prepared teeth were randomly divided into 3 groups of 19 teeth each and another 2 groups as positive and negative controls (9 teeth each). The experimental groups were dependent on the sealer used: AH-Plus, Apexit, and Ketac-Endo. The root canals were obturated using a lateral condensation technique. After 24 h the teeth were attached to microcentrifuge tubes with 2 mm of the root apex submerged in Brain Heart Infusion broth in glass test tubes. The coronal portions of the root canal filling materials were placed in contact with E. faecalis. The teeth were observed for bacterial leakage daily for 30 and 60 days. With the chi2 test for comparing pairs of groups at the 0.05 level (p 0.06), but Apexit had significantly higher leakage (p 0.05), but Apexit leaked more than AH-Plus. The conclusion drawn from this experiment was that epoxy resin root canal sealer was found to be more adaptable to the root canal wall and filling material than a calcium hydroxide sealer when bacterial coronal leakage was studied.

  9. Metachronous tubulovillous and tubular adenomas of the anal canal

    OpenAIRE

    NOZAWA, HIROAKI; ISHIHARA, SOICHIRO; Morikawa, Teppei; Tanaka, Junichiro; YASUDA, KOJI; Ohtani, Kensuke; Nishikawa, Takeshi; Tanaka, Toshiaki; Kiyomatsu, Tomomichi; Kawai, Kazushige; Hata, Keisuke; Kazama, Shinsuke; Yamaguchi, Hironori; Sunami, Eiji; Kitayama, Joji

    2015-01-01

    Anal canal adenoma is an extremely rare disease that has the potential to transform into a malignant tumor. We herein presented a rare case of metachronous multiple adenomas of the anal canal. A 48-year-old woman underwent total colonoscopy following a positive fecal blood test. A 9-mm villous polyp arising from the posterior wall of the anal canal was removed by snare polypectomy. Histologically, the tumor was tubulovillous adenoma with high-grade dysplasia and the cut end was negative for t...

  10. Route Selection by Tankers(Dirty) at the Suez Canal

    Institute of Scientific and Technical Information of China (English)

    Risto Laulajainen

    2007-01-01

    <正>The Suez Canal,attached route alternatives with traffic flows and areas are described and theoretical break-even points derived. Logistically,route selection depends on relative distances,the level of spot rates and canal dues,the sensitivity to change growing with rising rate levels.The connection is diluted by the canal /pipeline owners’ price differentiation and the charterers’ capital costs;interest on cargo and change of its value during transit.Ship-owners are largely neutral to route choice as long as rates and main cost items are directly related to distance.

  11. Les pathologies du Canal Péritonio-Vaginal

    OpenAIRE

    DJAZIRI, Sihem Fatima Zohra

    2014-01-01

    Les pathologies du canal péritonéo-vaginal, sont des affections congénitales dues à la persistance du canal au delà de la naissance. Elles regroupent les hernies inguinales et inguino-scrotales, les hydrocèles communicantes ou non, et les kystes du cordon spermatique. Notre travail est une étude rétrospective portant sur 309 malades opérés de pathologies du canal péritonio-vaginal dans le service de chirurgie infantile durant la période allant d’octobre 2011 jusqu'à octobre ...

  12. Cytogenetic findings in persons living near the Love Canal.

    Science.gov (United States)

    Heath, C W; Nadel, M R; Zack, M M; Chen, A T; Bender, M A; Preston, R J

    1984-03-16

    Cytogenetic analyses were performed on peripheral blood from 46 present or past residents of the area surrounding Love Canal, a former dump site for chemical wastes in Niagara Falls, NY. Participants included 17 persons in whom cytogenetic analyses had been performed in 1980 and 29 persons who had been living in 1978 in seven homes that directly adjoined the canal and in which environmental tests showed elevated levels of chemicals spreading from the canal. Frequencies of chromosomal aberrations and of sister chromatid exchange (SCE) did not differ significantly from control levels. For all participants, cigarette smoking was associated with an increase in sister chromatid exchange frequency.

  13. [An analysis of key points for root canal therapy technique].

    Science.gov (United States)

    Fan, M W

    2016-08-01

    The success rate of root canal therapy(RCT)have been improved continuously along with the advancement in RCT techniques in the past several decades. If standard procedures of modern RCT techniques are strictly followed, the success rate of RCT may exceed 90%. The success of RCT is mainly affected by such factors as clear concept of the anatomy of root canals, proper mechanical and chemical preparation and perfect filling of root canal system. If these factors are sufficiently noted, a success is easy to achieve. Even though the primary RCT fails, retreatment can further be conducted to save the diseased teeth. PMID:27511032

  14. TWO CANALS IN MAXILLARY FIRST MOLAR: A RARE DENTAL ENTITY

    Directory of Open Access Journals (Sweden)

    Dileep

    2016-01-01

    Full Text Available Root anatomy studies were divided into laboratory studies (In-Vitro, clinical root canal system anatomy studies (In vivo and clinical case reports of anomalies. Over 95% (95.9% of maxillary first molars had three roots and 3.9% had two roots. The incidence of fusion of any two or three roots was approximately 5.2%. Conical and C-shaped roots and canals were rarely found (0.12%.The fusion of the two buccal roots has the prevalence of 0.4% in maxillary first molars. Nevertheless, presence of only one buccal root with one canal is extremely rare.

  15. The classification and staging of cancerous growths of the anal canal

    International Nuclear Information System (INIS)

    In this chapter authors give information about frequency of cancerous growths of the anal canal, general analysis of observations the classification and staging of cancerous growths of the anal canal, clinical-anatomy classification of cancerous growths of the anal canal and staging of cancerous growths of anal canal

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    Lifescience Database Archive (English)

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  20. 75 FR 42678 - Intent To Prepare an Environmental Impact Statement for the Logan Northern Canal Reconstruction...

    Science.gov (United States)

    2010-07-22

    ... invites all interested individuals and organizations, public agencies, and Native American Tribes to... are as follows: Alternative 1: Divert LN Canal water into the existing LHPS Canal alignment, from...: Divert LN Canal water into the existing LHPS Canal alignment, from Logan River to Lundstrom Park,...

  1. Clinical Treatment and Anatomy Study of Maxillary First Molars with Five Root Canals

    Institute of Scientific and Technical Information of China (English)

    Kuo Wan; Shun-yun Luo; Ji-zhi Zhao; Hai-yun Wang; Lin Ma; Wen-dong Yang

    2011-01-01

    @@ THE purpose of root canal treatment is to thoroughly clean the root canal system and fill it in all its dimensions.1 To achieve this goal, the entire root canal system must be adequately debrided and completely filled.In clinical practice, variations in the canal morphology pose a constant challenge to Received for publication April 26, 2011.

  2. Analysis of kinematic, kinetic and electromyographic patterns during root canal preparation with rotary and manual instruments

    Directory of Open Access Journals (Sweden)

    Braulio Pasternak-Júnior

    2012-02-01

    Full Text Available OBJECTIVE: This study assessed the muscular activity during root canal preparation through kinematics, kinetics, and electromyography (EMG. MATERIAL AND METHODS: The operators prepared one canal with RaCe rotary instruments and another with Flexo-files. The kinematics of the major joints was reconstructed using an optoelectronic system and electromyographic responses of the flexor carpi radialis, extensor carpi radialis, brachioradialis, biceps brachii, triceps brachii, middle deltoid, and upper trapezius were recorded. The joint torques of the shoulder, elbow and wrist were calculated using inverse dynamics. In the kinematic analysis, angular movements of the wrist and elbow were classified as low risk factors for work-related musculoskeletal disorders. With respect to the shoulder, the classification was medium-risk. RESULTS: There was no significant difference revealed by the kinetic reports. The EMG results showed that for the middle deltoid and upper trapezius the rotary instrumentation elicited higher values. The flexor carpi radialis and extensor carpi radialis, as well as the brachioradialis showed a higher value with the manual method. CONCLUSION: The muscular recruitment for accomplishment of articular movements for root canal preparation with either the rotary or manual techniques is distinct. Nevertheless, the rotary instrument presented less difficulty in the generation of the joint torque in each articulation, thus, presenting a greater uniformity of joint torques.

  3. Duplication of the External Auditory Canal: Two Cases and a Review of the Literature

    Directory of Open Access Journals (Sweden)

    John K. Goudakos

    2012-01-01

    Full Text Available The objective of the present paper is to describe the clinical presentation, diagnostic process, surgical treatment, and outcome of 2 patients with first branchial cleft anomaly. The first case was an 8-year-old girl presented with an elastic lesion located in the left infra-auricular area, in close relation with the lobule, duplicating the external auditory canal. The magnetic resonance imaging revealed a lesion, appearing as a rather well-circumscribed mass within the left parotid gland and duplicating the ear canal. A superficial parotidectomy was subsequently performed, with total excision of the cyst. The second patient was a 15-year-old girl presented with a congenital fistula of the right lateral neck. At superficial parotidectomy, a total excision of the fistula was performed. During the operation the tract was recorded to lay between the branches of the facial nerve, extending with a blind ending canal parallel to the external acoustic meatus. Conclusively, first branchial cleft anomalies are rare malformations with cervical, parotid, or auricular clinical manifestations. Diagnosis of first branchial cleft lesions is achieved mainly through careful physical examination. Complete surgical excision with wide exposure of the lesion is essential in order to achieve permanent cure and avoid recurrence.

  4. Defective anterior wall of inguinal canal and its role in the pathophysiology of direct inguinal hernias

    Directory of Open Access Journals (Sweden)

    Abdolvahabi SA

    2002-06-01

    Full Text Available Regrding pathophysiology of direct inguinal hernias the following are pointed our:1-Absence of contribution of fascia of transverses abdominis muscle along with fascia transversalis in making posterior wall of the inguinal canal causing defect point in Hesselbachs triangle.2- Defects in protectin mechanisms of the inguinal canal such as: I shutter like effect of the arch of internal oblique and transverses abdominis muscles. ii Sphincter like effect of fascia of oblique muscle (anterior wall of canl.During several years of observation and practice in the field of surgical repair of hernias, a new phenomenon was observed regarding the etiology of direct hernias.Evaluation of superficial ring and Ant. Wall of inguinal canal in 25 patients showed that the ant. Wall was not perfect and the defect was seen as a spectrum of moderate defect to complete absence of the wall. This phenomenon may be a newly observed mechanism in pathology of direct inguinal hernia that might help the operative repair. Taking this into account, i.e. repair of this defect, might help the classic herniorrhaphy techniques

  5. Transmastoid Approach for Resurfacing the Superior Semicircular Canal Dehiscence with a Dumpling Structure

    Institute of Scientific and Technical Information of China (English)

    Xiao-Bo Ma; Rong Zeng; Guo-Peng Wang; Shu-Sheng Gong

    2015-01-01

    Background:Superior semicircular canal dehiscence (SSCD) is gradually recognized by otologists in recent years.The patients with SSCD have a syndrome comprising a series of vestibular symptoms and hearing function disorders which can be cured by the operation.In this study,we evaluated the characteristics of patients with SSCD and determined the effectiveness of treating this syndrome by resurfacing the canal via the transmastoid approach using a dumpling structure.Methods:Patients with SSCD,confirmed by high-resolution computed tomography and hospitalized at Beijing Tongren Hospital between November 2009 and October 2012,were included in the study.All of the patients underwent the unilateral transmastoid approach for resurfacing the canal,and received regular follow-up after surgery.Data from preoperative medical records and postoperative follow-up were comparatively analyzed to evaluate the effect of surgery.Results:In total,10 patients and 13 ears (three left ears,four right ears,three bilateral ears) were evaluated in the study,which included 7 men and 3 women.Different symptoms and distinctive manifestations of vestibular evoked myogenic potential were found in these patients.After surgery,4 patients had complete resolution,5 had partial resolution,and 1 patient,with bilateral SSCD,had aggravation.None of the patients suffered from serious complications such as sensorineural hearing loss,facial paralysis,cerebrospinal fluid leakage,or intracranial hypertension.Conclusions:In patients with unilateral SSCD,resurfacing the canal via the transmastoid approach using a dumpling structure is an effective and safe technique.However,more consideration is needed for patients with bilateral SSCD.

  6. Transmastoid Approach for Resurfacing the Superior Semicircular Canal Dehiscence with a Dumpling Structure

    Directory of Open Access Journals (Sweden)

    Xiao-Bo Ma

    2015-01-01

    Full Text Available Background: Superior semicircular canal dehiscence (SSCD is gradually recognized by otologists in recent years. The patients with SSCD have a syndrome comprising a series of vestibular symptoms and hearing function disorders which can be cured by the operation. In this study, we evaluated the characteristics of patients with SSCD and determined the effectiveness of treating this syndrome by resurfacing the canal via the transmastoid approach using a dumpling structure. Methods: Patients with SSCD, confirmed by high-resolution computed tomography and hospitalized at Beijing Tongren Hospital between November 2009 and October 2012, were included in the study. All of the patients underwent the unilateral transmastoid approach for resurfacing the canal, and received regular follow-up after surgery. Data from preoperative medical records and postoperative follow-up were comparatively analyzed to evaluate the effect of surgery. Results: In total, 10 patients and 13 ears (three left ears, four right ears, three bilateral ears were evaluated in the study, which included 7 men and 3 women. Different symptoms and distinctive manifestations of vestibular evoked myogenic potential were found in these patients. After surgery, 4 patients had complete resolution, 5 had partial resolution, and 1 patient, with bilateral SSCD, had aggravation. None of the patients suffered from serious complications such as sensorineural hearing loss, facial paralysis, cerebrospinal fluid leakage, or intracranial hypertension. Conclusions: In patients with unilateral SSCD, resurfacing the canal via the transmastoid approach using a dumpling structure is an effective and safe technique. However, more consideration is needed for patients with bilateral SSCD.

  7. Only fixation for lumbar canal stenosis: Report of an experience with seven cases

    Directory of Open Access Journals (Sweden)

    Atul Goel

    2014-01-01

    Full Text Available Study Design and Objective: The author reports experience with treatment of degenerative lumbar canal stenosis that involved fixation-arthrodesis of the affected spinal segment using "double insurance" transarticular screws for each joint. No direct bone, ligament or disc resection is done for decompression of the spinal dural tube or root canal. Methods and Summary of Background Data: During the period March 2011-September 2011, seven patients having lumbar canal stenosis were treated with a modification of transarticular method of screw fixation that involved insertion of two or "double insurance" screws at each articular joint. The operation involved section of the spinous process at its base, opening up of the facet joint, denuding of articular cartilage, insertion of intra-articular bone graft and insertion of two transarticular screws at each facet joint. The fixation was done in four levels in two patients, at three levels in four patients and at two levels in one patient. Oswestry disability index and visual analog scale were used to clinically assess the patients before and after the surgery and at follow-up. Results: During the average period of follow-up of 26.9 months (range 24-30 months, there was varying degree of recovery of symptoms. The procedure resulted in firm stabilization and fixation of the spinal segment and provided a ground for arthrodesis. During the period of follow-up, one patient underwent re-exploration and decompressive laminectomy as she continued to have significant pain symptom. Conclusions: Vertical instability and telescoping, listhesis or overriding of the facets on physical activity seems to be the defining phenomenon in the pathogenesis of lumbar canal stenosis. The clinical outcome in our patients suggest that fixation of the spinal segment can be a rationale form of treatment. "Double insurance" transarticular method of treatment is a simple, safe, and effective method of spinal stabilization.

  8. Comparison of antimicrobial substantivity of root canal irrigants in instrumented root canals up to 72 h: An in vitro study

    Directory of Open Access Journals (Sweden)

    M N Shahani

    2011-01-01

    Full Text Available Disinfection of the root canal system is one of the primary aims of root canal treatment. This can be achieved through the use of various antimicrobial agents in the form of irrigants and medicaments. The antimicrobial substantivity of 2% chlorhexidine gluconate, 1% povidone iodine, 2.5% hydrogen peroxide followed by 2% sodium hypochlorite, and 2% sodium hypochlorite alone as irrigants was assessed in instrumented root canals. 2% chlorhexidine showed antimicrobial substantivity lasting up to 72 h, followed by 1% povidone iodine, and 2% sodium hypochlorite. Thus 2% chlorhexidine should be used as a final rinse irrigant in endodontic treatment protocols.

  9. Seepage from canals having variable shape and partial lining

    Science.gov (United States)

    Mirnateghi, A.; Bruch, J. C.

    1983-07-01

    The numerical models presented here are solutions to the steady two-dimensional flow through a porous medium from canals of variable shape with partial lining. Two main cases are studied. The first case is the seepage flow from canals with impervious lining on their sloping sides. The second case is for seepage from canals in which the impervious lining is located on the base of the canal and the sides are unlined. The Baiocchi transformation and method is used to develop a boundary value problem which is then solved by the finite-difference successive over-relaxation method with projection. A sample problem of each case is presented. The discharge rates and free surfaces of the seepage flows are obtained through the numerical scheme, and are compared with available analytical results.

  10. Optimal volume of local anaesthetic for the adductor canal block

    DEFF Research Database (Denmark)

    Jæger, P.; Jenstrup, M. T.; Lund, J.;

    2015-01-01

    Background: Theoretically, the ideal volume of local anaesthetic for adductor canal block (ACB) would ensure sufficient filling ofthe canal and avoid proximal spread to the femoral triangle. In this dose-finding study, we aimed to investigate the minimaleffective volume for an ACB needed to fill...... the adductor canal distally in at least 95% of patients (ED95). Methods: We performed a blinded trial, enrolling 40 healthy men. All subjects received an ACB with lidocaine 1%. Volumes wereassigned sequentially to the subjects using the continual reassessment method followed by Bayesian analysis to determine...... theED95. Distal filling of the adductor canal was assessed by magnetic resonance imaging (primary outcome). Secondary outcomeswere the effect of volume on proximal spread to the femoral triangle (also assessed by magnetic resonance imaging), quadricepsmuscle weakness (decrease by ≥25% from baseline...

  11. Synergistic growth effect among bacteria recovered from root canal infections

    Directory of Open Access Journals (Sweden)

    Gil Moreira Júnior

    2011-09-01

    Full Text Available The objective of this study was to determine the ecological relationships between bacterial species that colonize infected root canals. Root canal bacteria recovered from one patient with pulp canal necrosis were evaluated in vitro for synergistic and antagonistic activities determined by mono and co-culture growth kinetics and the production of bacteriocin-like substances using the double layer diffusion method. Peptostreptococcus prevotii triggered a significant increase of Fusobacterium nucleatum growth, while the former bacteria did not affect the growth of P. prevotii. The bacterial species did not produce antagonism activity against itself or against any of the other two species. Despite many studies have demonstrated the capability of root canal microorganisms to produce antagonistic substances, these in vitro experimental tests show the synergistic effect of P. prevotii on the growth of F. nucleatum.

  12. Atypical situations in root canals anatomy of human mandibular premolars

    Directory of Open Access Journals (Sweden)

    Fabrício SCAINI

    2005-05-01

    Full Text Available The knowledge of the teeth internal anatomy that will receive endodontic treatment is very important for the success of the treatment and prognosis of those teeth. In this study, the morphological variations that may occur in relation to the number of root canals present in the premolar mandibular teeth group were discussed, as well as the most efficient methods to diagnose the existence of these variations, in order to have a clearer diagnosis of the number of root canals to be treated.A case of an endodontic treatment of a mandibular premolar with 4 root canals was reported and some cases of endodontic treatment in mandibular premolars with 1, 2 and 3 root canals were shown.

  13. Research progress of antagonistic interactions among root canal irrigations disease

    Directory of Open Access Journals (Sweden)

    Chen QU

    2013-07-01

    Full Text Available Root canal therapy is the most effective way to treat various pulposis and periapical disease. Simple mechanical apparatus can not clean root canal thoroughly, but may affect tight filling instead. It can achieve a satisfactory cleansing effect only when it is combined with a chemical solution. Irrigation fluid for root canal should possess the properties of tissue dissolution, antimicrobial, lubrication, and removal of smear layer. So far, no solution is able to fulfill all these functions. Therefore, a combined use of multiple irrigation solutions is suggested. It can not only achieve good effect in cleaning and disinfection, also it can lower the concentration of different solutions, thus reducing the side effects. Nevertheless, some experiments proved that antagonism existed among the chemicals used for irrigations. The purpose of present article is to review the antagonistic effect among the chemicals used for irrigation when they are used together for root canal treatment.

  14. Canals, Midview Lateral, Published in 2002, Duchesne County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Canals dataset, was produced all or in part from Other information as of 2002. It is described as 'Midview Lateral'. Data by this publisher are often provided...

  15. Root canal irrigants: a review of their interactions, benefits, and limitations.

    Science.gov (United States)

    Jena, Amit; Sahoo, Sanjit Kumar; Govind, Shashirekha

    2015-04-01

    Endodontic treatment success depends on a combination of appropriate instrumentation, effective irrigation and decontamination of root canal spaces to apices, and obturation of the root canals. Irrigation of the root canal is paramount in determining periapical tissue healing. This article reviews presently available root canal irrigants, their interactions, advantages, and limitations. For this review, the authors performed a Medline search for all English language articles published through January 2014 with "root canal irrigants" and "endodontic irrigants" as keywords. PMID:25821937

  16. Canals in the Roof of the Pharynx :Anatomic Study and their Clinical Meaning

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    1 IntroductionThe palatovaginal canal and the vomerovaginal canal are small canals which connect the roof of the nasopharynx to the posterior wall of the pterygopalatine fossa. The pterygopalatine fossa represents a major pathway for spread of malignant tumors and infections. In most of the classic anatomy texts brief descriptions of the palatovaginal canal and the vomerovaginal canal are provided. There is still a scarcity of studies comparing the radiologic and microdissection findings~([1]). The aim of t...

  17. The Evaluation of Lumbar Spinal Canal Diameters by MRI

    Directory of Open Access Journals (Sweden)

    Mehrnaz Mashoufi

    2010-05-01

    Full Text Available Background/Objective: Lumbar spinal stenosis is the common cause of low back pain. MRI is the best modality for diagnosis of spinal canal stenosis. The aim of this study is to evaluate lumbar spinal canal diameters and relationship with gender, age, stature, weight and job."nPatients and Methods: One-hundred men and 100 women in the age range of 25 to 40 years from East Azarbayjan who were referred to Sheikholrais MRI Center were selected. The diameters of the spinal canal were measured on the midsagittal and axial section on T2 weighted images by 0.3 T MRI Unite. The results of measurements were analyzed by SPSS software. "nResults: The results showed that the least anteroposterior diameter was at the third lumbar vertebra but the narrowest transverse diameter was at the first lumbar vertebra. The mean anteroposterior diameter of the lumbar spinal canal decreased from the first to the third lumbar vertebra, followed by an increase from the third to the fifth. From the first to the fifth lumbar vertebra, there was an increase in the mean transverse diameters. The mean transverse diameter in the middle part of the vertebra is longer than the lower part. A frank relation was seen between the gender of physical workers with lumbar spinal canal stenosis, although there was no relation between age, stature, and weight with lumbar spinal canal stenosis."nConclusion: Considering the high incidence of lumbar canal stenosis and the relationship with heavy manual work, it is recommended that a plain radiography is taken before choosing heavy manual work and exercises. People whose canal is relatively narrow should be refused from heavy manual work and exercises.

  18. Absent posterior semicircular canal: HRCT feature of Waardenburg syndrome

    OpenAIRE

    Sandeep M Mahajan; Manish Pithwa; Apeksha Chavan; Deepti Pimple

    2012-01-01

    Absence of posterior semicircular canal is a rare condition, having been reported with only a few syndromes such as Waardenburg syndrome (WS), Alagellie, CHARGE, and Goldenhaar syndromes. We report a 12- year old male with bilateral absent posterior semicircular canals. These phenotypic characteristics of the patient favored the diagnosis of WS. WS is a rare autosomal dominant condition characterized by sensorineural hearing loss, in conjunction with pigmentary abnormalities and defects of th...

  19. Bifid mandibular canal: a rare or underestimated entity?

    Directory of Open Access Journals (Sweden)

    Ibrahim Nasseh

    2016-10-01

    Full Text Available One of the rare anatomical variations that can be of significant importance for the dentist is the bifid mandibular canal. Many complications can occur from this condition such as failure of anesthesia when performing inferior alveolar nerve block, difficulties during the surgical extraction of the third mandibular molar, and during implants placement. Therefore, good knowledge of this condition is essential. In this report, we describe the radiographic finding of a unilateral bifid mandibular canal.

  20. An investigation of the geochemistry and petrology of canal sediments

    OpenAIRE

    Dodd, Juliet S.

    2000-01-01

    Canals are artificial waterways, which are distinct from natural aquatic systems. As a result of their industrial heritage they have experienced high loadings of anthropogenic material, and consequently their sediments tend to have a bulk composition that is distinct from natural sediment. It is therefore expected that the geochemical behaviour of canal sediment may deviate significantly from that of natural sediment. This study investigates and contrasts the geochemistry and petrology of a r...

  1. Predictive control applied to a water canal prototype

    OpenAIRE

    Canarias, Daniel; Figueiredo, João; Rijo, Manuel

    2006-01-01

    Predictive control is an intelligent tool to manage complex systems. This control strategy is getting more and more application in industrial fields. This paper shows the application of the predictive control methodology to a water distribution canal. Water canals are complex hydraulic systems because they are open and big scale systems, characterized by big delays and great inertia. Many models and control strategies have already been simulated using linear control theory. In the present stu...

  2. Root canal preparation in endodontics: conventional versus laser methods

    Science.gov (United States)

    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.

  3. Verrucous Carcinoma in External Auditory Canal – A Rare Case

    Directory of Open Access Journals (Sweden)

    Md Zillur Rahman

    2013-05-01

    Full Text Available Verrucous carcinoma is a variant of squamous cell carcinoma. It is of low grade malignancy and rarely present with distant metastasis. Oral cavity is the commonest site of this tumour, other sites are larynx, oesophagus and genitalia. Verrucous carcinoma in external auditory canal is extremely rare. This is the presentation of a 45 years old woman who came to the ENT & Head Neck Surgery department of Delta medical college, Dhaka, Bangladesh with discharging left ear and impairment of hearing on the same side for 7 years. Otoscopic examination showed a mass occupying almost whole of the external auditory canal and the overlying skin was thickened, papillary and blackish. Cytology from external auditory canal scrap showed hyperkeratosis and parakeratosis. External auditory canal bone was found eroded at some parts. Excision of the mass was done under microscope. Split thickness skin grafting was done in external auditory canal. The mass was diagnosed as verrucous carcinoma on histopathological examination. Afterwards she was given radiotherapy. Six months follow up showed no recurrence and healthy epithelialization of external auditory canal.

  4. Long-term cytotoxic effects of contemporary root canal sealers

    Directory of Open Access Journals (Sweden)

    Emmanuel Joao Nogueira Leal da SILVA

    2013-03-01

    Full Text Available Objectives The aim of the present study was to investigate the effects of root canal sealers on the cytotoxicity of 3T3 fibroblasts during a period of 5 weeks. Material and Methods Fibroblasts (3T3, 1×105 cells per well were incubated with elutes of fresh specimens from eight root canal sealers (AH Plus, Epiphany, Endomethasone N, EndoREZ, MTA Fillapex, Pulp Canal Sealer EWT, RoekoSeal and Sealapex and with elutes of the same specimens for 5 succeeding weeks after immersing in simulated body fluid. The cytotoxicity of all root canal sealers was determined using the MTT assay. Data were analyzed using ANOVA and Tukey's test. Results RoekoSeal was the only sealer that did not show any cytotoxic effects (p<0.05. All the other tested sealers exhibited severe toxicity initially (week 0. MTA Fillapex remained moderately cytotoxic after the end of experimental period. Toxicity of the other tested sealers decreased gradually over time. The evaluated root canal sealers presented varying degrees of cytotoxicity, mainly in fresh mode. Conclusions RoekoSeal had no cytotoxic effect both freshly mixed and in the other tested time points. MTA Fillapex was associated with significantly less cell viability when compared to the other tested root canal sealers.

  5. Influence of root curvature’s initial position on apical deviation occurrence after oscillatory preparation in simulated root canals

    Directory of Open Access Journals (Sweden)

    Tiago André Fontoura de Melo

    2011-10-01

    Full Text Available Introduction and objective: This study aimed to analyze the influence of root curvature’s initial position on apical deviation occurrence after oscillatory system preparation. Material and methods: For this purpose, we used twenty simulated root canals with 21 mm length and 30 degree angle, which were divided into two experimental groups according to curvature’s initial position: 8 mm (group A and 12 mm (group B short of the canal orifice. The canals were prepared using crown-down technique, and memory instrument was size #30. For apical deviation analysis, before and after preparation, canals were filled with Indian ink and standardly photographed with the aid of a platform. After that, the images were manipulated by Adobe Photoshop® software, through superimposing pre- and post-operative images. Deviation occurrence was measured 1 mm short of working length and at the middle of the curvature by using the ruler tool. Data were subjected to analysis of variance (ANOVA with significance level set at 5%. Results: Although group B showed a significantly greater deviation mean than group A, no significant interaction was verified between the analysis site and the experimental group. Conclusion: According to the present data, it could be observed that the smaller the curvature radius, the greater the deviation. Concerning to the analysis site, it could be noted that the area 1 mm short of working length presented a higher deviation than the point at the middle of the curvature.

  6. Developmentof the safety monitoring system of hydraulic structuresof the Moscow canal

    OpenAIRE

    Levachev Stanislav Nikolaevich; Fedorova Tat’yana Sergeevna

    2015-01-01

    The basis of the enterprise “Moscow Canal” in its present state is the canal Moscow - Volga constructed in 1937. Today “Moscow Canal” is the biggest water transport and water industry complex. It has 10 filiations and solves a substantial complex of tasks. One of the most important part of hydraulic structures operation is their observation or monitoring of their safety, which gives us timely and adequate picture of their work and helps to forecast and prevent emergency situations.The article...

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

    Science.gov (United States)

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

    2016-01-01

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

  8. Assessment of the wetting behavior of three different root canal sealers on root canal dentin

    Directory of Open Access Journals (Sweden)

    Muralidhar Tummala

    2012-01-01

    Full Text Available Aim: The objective of the present study was to evaluate and compare the wetting behavior of three different root canal sealers on the root canal dentin surface treated with irrigants and their combination. Materials and Methods: Decoronation and apical third resections of 27 extracted single-rooted human mandibular premolars were done. The roots were then split longitudinally into two halves, and randomly assigned into three treatment groups (n=18. The root dentin surfaces in Group1, Group 2 and Group 3 were treated with 17% ethylene diamine tetra acetic acid (EDTA, 3% sodium hypochlorite (NaOCl and combination of 17% EDTA and 3% NaOCl, respectively. Each group was subdivided into three subgroups of 6 specimens each, depending on the the sealer used, i.e. sub group A. zinc oxide (ZnOE, sub group B. AH plus, subgroup C. Guttaflow sealer, respectively. The contact angle was measured using First Ten Angstroms (FTA 200 dynamic contact angle analyzer. Results: The contact angle values for AH Plus sealer were significantly lower when compared to the other two sealer groups. Conclusion: The wettability of AH Plus sealer on the root surface dentin was found to be better than Gutta-Flow and ZnOE sealer.

  9. Microbiological evaluation of infected root canals and their correlation with pain

    Directory of Open Access Journals (Sweden)

    Nadine Luísa Soares de Lima Guimarães

    2012-01-01

    Full Text Available Introduction and objective: The aim of this study was to evaluate the endodontic microbiota of human teeth without pulp vitality presenting radiographically visible periapical lesions and its correlation with pre- and postoperative pain symptomatology. Material and methods: Sixteen young adult patients, both genders, aging from 18 to 45 years, presenting 21 single-rooted teeth with pulp necrosis and needing endodontic treatment were selected in the multidisciplinary clinic at the University of Fortaleza (UNIFOR. After crown surgical access, the ��������������root canals were embedded with 0.9% saline solution and the material from root canals was collected ���������������������������������������������� withhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhsterile paper point. The paper points were placed into Stuart transport medium and sent to the microbiology laboratory of the University of Fortaleza. Isolation and identification of bacteria were made by culture technique. The cleaning and shaping of root canals was performed by ��������������� ����� ���������������������������� crown-down technique..............................Intra-canal medication comprised calcium hydroxide mixed with chlorhexidine and after 14 days the canals were filled. Patients were asked about the occurrence of pain before treatment and 24 hours after cleaning and shaping procedures. Results: The most prevalent microbial group was Streptococcus sp. followed by Fusobacterium nucleatum, although Gram-positive cocci, non-sporulating Gram-positive bacilli, Gram-negative bacilli, pigmented Gram-negative bacilli, Veillonella, Staphylococcus aureus, Pseudomonas sp. were also frequently isolated. Conclusion: According to the results, it can be concluded that Fusobacterium

  10. A Case of Extensive Spinal Cysticercosis Involving the Whole Spinal Canal in a Patient with a History of Cerebral Cysticercosis

    OpenAIRE

    Shin, Dong Ah; Shin, Hyun Chul

    2009-01-01

    Although cysticercosis is the most common parasitic disease affecting the central nervous system, spinal cysticercosis is rare. A rare form of spinal cysticercosis involving the whole spinal canal is presented. A 45-year-old Korean male had a history of intracranial cysticercosis and showed progressive paraparesis. Spinal magnetic resonance scan showed multiple cysts compressing the spinal cord from C1 to L1. Three different levels (C1-2, T1-3, and T11-L1) required operation. Histopathologica...

  11. Development of an artificial neural network-based software for prediction of power plant canal water discharge temperature

    Energy Technology Data Exchange (ETDEWEB)

    Romero, C.E.; Shan, J.F. [Lehigh University, Bethlehem, PA (United States). Energy Research Center

    2005-11-01

    Power plant cooling water systems that interact with nearby effluents are complex non-linear, large-time-delay systems. A neural network-based software tool was developed for prediction of the canal water discharge temperature at a coal-fired power plant as a function of plant operating parameters and local weather conditions, including tide information. The plant has four units totaling an installed capacity of 1550 MW and its water thermal discharge is environmentally regulated. In the summer months, when the price of electricity is very profitable and the risk of exceeding the canal temperature limit is greater, the tradeoff between maximum generation and environmental compliance violations is financially significant. The software is a predictive tool to assist in scheduling load generation among the plant's four units without exceeding a thermal discharge limit of 95{sup o}F. Back propagation neural network architectures were trained using plant operating data with an 'off-set' component. The artificial intelligence models produced reasonable trends for year-round prediction and different operational scenarios. Comparison of measured and predicted canal temperatures indicated an accuracy of less than 0.3{sup o}F over the range between 90 and 95{sup o}F. The software tool was developed as an Object Linking and Embedding (OLE) for Process Control (OPC) client, with real-time communication and interface with the plant Distributed Control System (DCS).

  12. Metachronous tubulovillous and tubular adenomas of the anal canal.

    Science.gov (United States)

    Nozawa, Hiroaki; Ishihara, Soichiro; Morikawa, Teppei; Tanaka, Junichiro; Yasuda, Koji; Ohtani, Kensuke; Nishikawa, Takeshi; Tanaka, Toshiaki; Kiyomatsu, Tomomichi; Kawai, Kazushige; Hata, Keisuke; Kazama, Shinsuke; Yamaguchi, Hironori; Sunami, Eiji; Kitayama, Joji; Fukayama, Masashi; Watanabe, Toshiaki

    2015-01-01

    Anal canal adenoma is an extremely rare disease that has the potential to transform into a malignant tumor. We herein presented a rare case of metachronous multiple adenomas of the anal canal. A 48-year-old woman underwent total colonoscopy following a positive fecal blood test. A 9-mm villous polyp arising from the posterior wall of the anal canal was removed by snare polypectomy. Histologically, the tumor was tubulovillous adenoma with high-grade dysplasia and the cut end was negative for tumor cells. Six years later, an elevated lesion, macroscopically five millimeters in size, was detected in the left wall of the anal canal in a follow-up colonoscopy. Local excision of the tumor was performed, and the lesion was pathologically confirmed to be tubular adenoma with high-grade dysplasia limited to the mucosa. The patient is currently alive without any evidence of recurrence for six months after surgery. Although she had a past history of cervical cancer, the multiple tumors arising in the anal canal were unlikely to be related to human papilloma virus infection. Our case report underscores the importance of careful observations throughout colonoscopy to detect precancerous lesions, particularly in anatomically narrow segments. PMID:26249723

  13. Micro-Machined Flow Sensors Mimicking Lateral Line Canal Neuromasts

    Directory of Open Access Journals (Sweden)

    Hendrik Herzog

    2015-08-01

    Full Text Available Fish sense water motions with their lateral line. The lateral line is a sensory system that contains up to several thousand mechanoreceptors, called neuromasts. Neuromasts occur freestanding on the skin and in subepidermal canals. We developed arrays of flow sensors based on lateral line canal neuromasts using a biomimetic approach. Each flow sensor was equipped with a PDMS (polydimethylsiloxane lamella integrated into a canal system by means of thick- and thin-film technology. Our artificial lateral line system can estimate bulk flow velocity from the spatio-temporal propagation of flow fluctuations. Based on the modular sensor design, we were able to detect flow rates in an industrial application of tap water flow metering. Our sensory system withstood water pressures of up to six bar. We used finite element modeling to study the fluid flow inside the canal system and how this flow depends on canal dimensions. In a second set of experiments, we separated the flow sensors from the main stream by means of a flexible membrane. Nevertheless, these biomimetic neuromasts were still able to sense flow fluctuations. Fluid separation is a prerequisite for flow measurements in medical and pharmaceutical applications.

  14. Origin and evolution of the canal raphe system in diatoms.

    Science.gov (United States)

    Ruck, Elizabeth C; Theriot, Edward C

    2011-11-01

    One lineage of pennate diatoms has a slit through the siliceous cell wall, called a "raphe," that functions in motility. Raphid pennate diatoms number in the perhaps tens of thousands of species, with the diversity of raphe forms potentially matching this number. Three lineages-the Bacillariales, Rhopalodiales, and Surirellales-possess a complex and presumably highly derived raphe that is physically separated from the cell interior, most often by a set of siliceous braces. Because the relationship among these three lineages is unclear, the number of origins of the canal raphe system and the homology of it and its constitutive parts among these lineages, is equally unclear. We reconstructed the phylogeny of raphid pennate diatoms and included, for the first time, members of all three canal raphid diatom lineages, and used the phylogeny to test specific hypotheses about the origin of the canal raphe. The canal raphe appears to have evolved twice, once in the common ancestor of Bacillariales and once in the common ancestor of Rhopalodiales and Surirellales, which form a monophyletic group in our analyses. These results recommend careful follow-up morphogenesis studies of the canal raphe in these two lineages to determine the underlying developmental basis for this remarkable case of parallel evolution.

  15. The Effect of Using Patency File on Apical Transportation in Canals Prepared with Passive Step Back Technique

    Directory of Open Access Journals (Sweden)

    S M Hasheminia

    2004-10-01

    Full Text Available Background: The purpose of this study was to assess the effect of patency file on apical transportation in curved canals prepared with passive step back (P.S.B technique. Methods: This is an interceptive experimental, Invitro, study. Human extracted first permanent molars with 19-23mm length and curvature of 15-35 degrees (Schneider method were considered for use in this study. Simple sampling was done and 35 teeth for each group was selected. In experimental group A canal preparation was done with P.S.B technique and usage of a # 10 file (as Patency file between successive files. In experimental group B preparation was done in the same way except for usage of patency file. Pre and post operative radiographs were taken with similar condition. Radiographs were scanned and changes in canal curvature was determined using four different methods [Schneider, Weine, Long – Axis techniques (L. A.T, and Digital image overlay technique (overlay. T] , using Idrisi for windows and AutoCAD softwares. Results: The mean of canal transportation angle in experimental group A with Schneider, Weine , LAT, and Over Lay techniques was: 7.006 ± 3.478, 12. 285 ± 6.032, 4.376 ± 3.516, 3.147 ± 2.744 respectively. Mean of canal transportation angle in experimental group B with the same methods was also determined: 8.009 ± 4.178, 13.55 ± 7.602, 9.464 ± 5.384, and 9.641 ± 5.382 respectively. T- test statistical analysis shows that there are no significant differences between the mean of canal transportation angles in two groups as measured by Schneider and Weine method (P>0.05. Mann- Whitney test shows that there are statistically significant differences between two groups as measured by LAT and Over Lay techniques (P<0.001. Conclusions: Results of this study shows that patency file in conjunction with P.S.B techniques causes significant reduction in apical transportation angle. Shortcomings of Schneider method in determination of canal curvature and specially

  16. Comparison of two sonic handpieces during the preparation of simulated root canals.

    Science.gov (United States)

    Dummer, P M; Hutchings, R; Hartles, F R

    1993-05-01

    The objective of this study was to assess and compare two sonic handpieces during the preparation of simulated root canals. A total of 60 simulated canals in clear resin blocks of various angles and positions of curvature were prepared using Shaper files activated either by an MM1500 Sonic Air or an MM1400 Mecasonic handpiece. Each handpiece was used to prepare 30 canals using an identical preparation procedure which involved a linear filing motion and an anticurvature technique in curved canals. The efficacy of the handpieces was determined for straight and curved canals separately and included an assessment of loss of canal length, weight loss from the blocks, smoothness of canal walls, transportation and overall shape of the prepared canals. Canals were prepared rapidly and effectively by both handpieces. Overall, the MM1500 handpiece was associated with significantly less distance loss (P canals (8%) had hour-glass shapes displaying zips and elbows, each handpiece created two. Only two canals (4%) had danger zones, both were created by the MM1400 handpiece. There was little difference between the handpieces in terms of the smoothness of canal walls, the direction and amount of transportation or the overall shape of canals. Under the conditions of this study, the new MM1400 Mecasonic handpiece performed as well as the established MM1500 Sonic Air. PMID:8406963

  17. Spatial orientation of semicircular canals and afferent sensitivity vectors in pigeons

    Science.gov (United States)

    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

  18. Commentaires sur la valeur piscicole du Canal de Roubaix (Nord

    Directory of Open Access Journals (Sweden)

    ARRIGNON J.

    1970-10-01

    Full Text Available La population piscicole du Canal de ROUBAIX a été inventoriée par pêche électrique. Trois passages, suivis chacun de l'enlèvement des poissons capturés, ont été opérés dans chacun des trois Secteurs d'inventaire. Le peuplement le plus probable ainsi estimé (par la méthode De Lury,est en rapport avec le degré de pollution du canal. On constate aussi queles poissons se cantonnent le long des berges, sur une largeur de 2 à 3mètres.L'estimation à l'hectare représente donc en réalité le stock d'une zone n'ayant que 25 % de la surface totale du Canal. Les poissons contrôlés sont pour la plupart des poissons de repeuplement.

  19. Temporal Bone Fracture Causing Superior Semicircular Canal Dehiscence

    Directory of Open Access Journals (Sweden)

    Kevin A. Peng

    2014-01-01

    Full Text Available Importance. Superior semicircular canal dehiscence (SCD is a third window lesion of the inner ear causing symptoms of vertigo, autophony, tinnitus, and hearing loss. A “two-hit” hypothesis has traditionally been proposed, whereby thinly developed bone overlying the superior canal is disrupted by a sudden change in intracranial pressure. Although the symptoms of SCD may be precipitated by head injury, no previous reports have described a temporal bone fracture directly causing SCD. Observations. Two patients sustained temporal bone fractures after closed head trauma, and developed unilateral otologic symptoms consistent with SCD. In each instance, computed tomography imaging revealed fractures extending through the bony roof of the superior semicircular canal. Conclusions and Relevance. Temporal bone fractures, which are largely treated nonoperatively, have not previously been reported to cause SCD. As it is a potentially treatable entity, SCD resulting from temporal bone fracture must be recognized as a possibility and diagnosed promptly if present.

  20. Bioceramic-Based Root Canal Sealers: A Review

    Science.gov (United States)

    Che Ab Aziz, Zeti A.

    2016-01-01

    Bioceramic-based root canal sealers are considered to be an advantageous technology in endodontics. The aim of this review was to consider laboratory experiments and clinical studies of these sealers. An extensive search of the endodontic literature was made to identify publications related to bioceramic-based root canal sealers. The outcome of laboratory and clinical studies on the biological and physical properties of bioceramic-based sealers along with comparative studies with other sealers was assessed. Several studies were evaluated covering different properties of bioceramic-based sealers including physical properties, biocompatibility, sealing ability, adhesion, solubility, and antibacterial efficacy. Bioceramic-based sealers were found to be biocompatible and comparable to other commercial sealers. The clinical outcomes associated with the use of bioceramic-based root canal sealers are not established in the literature. PMID:27242904

  1. Tullio phenomenon in superior semicircular canal dehiscence syndrome.

    Science.gov (United States)

    Basura, Gregory J; Cronin, Scott J; Heidenreich, Katherine D

    2014-03-18

    Tullio phenomenon refers to eye movements induced by sound.(1) This unusual examination finding may be seen in superior semicircular canal dehiscence (SSCD) syndrome.(2) This disorder is due to absent bone over the superior semicircular canal (figure). Patients complain of dizziness triggered by loud sound, aural fullness, autophony, and pulsatile tinnitus. When Tullio phenomenon exists in SSCD syndrome, the patient develops a mixed vertical-torsional nystagmus in which the slow phase rotates up and away from the affected ear (video on the Neurology® Web site at Neurology.org). This pattern of nystagmus aligns in the plane of the dehiscent semicircular canal and is due to excitation of its afferent nerves.

  2. Bioceramic-Based Root Canal Sealers: A Review

    Directory of Open Access Journals (Sweden)

    Afaf AL-Haddad

    2016-01-01

    Full Text Available Bioceramic-based root canal sealers are considered to be an advantageous technology in endodontics. The aim of this review was to consider laboratory experiments and clinical studies of these sealers. An extensive search of the endodontic literature was made to identify publications related to bioceramic-based root canal sealers. The outcome of laboratory and clinical studies on the biological and physical properties of bioceramic-based sealers along with comparative studies with other sealers was assessed. Several studies were evaluated covering different properties of bioceramic-based sealers including physical properties, biocompatibility, sealing ability, adhesion, solubility, and antibacterial efficacy. Bioceramic-based sealers were found to be biocompatible and comparable to other commercial sealers. The clinical outcomes associated with the use of bioceramic-based root canal sealers are not established in the literature.

  3. Influence of Root Canal Tapering on Smear Layer Removal.

    Science.gov (United States)

    Zarei, Mina; Javidi, Maryam; Afkhami, Farzaneh; Tanbakuchi, Behrad; Zadeh, Mohsen Movahed; Mohammadi, Marzieh Maghadam

    2016-04-01

    The purpose of the study presented here was to compare the influence of root canal taper on the efficacy of irrigants and chelating agents in smear layer removal. Eighty mesial roots of molar teeth were selected and prepared with rotary instruments. In group A, file 30/0.02 and in group B, file 30/0.4 were placed at working length and the smear layer was removed. In groups C and D, root canal preparation was the same as in groups A and B, respectively, except that the smear layer was not removed. The amount of the smear layer was quantified using a scanning electron microscope. Greater smear layer was detected in the apical portion of each group, whereas no significant difference was detected between groups in other portions. No statistical difference was found between canals with different tapers. PMID:27348950

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

    International Nuclear Information System (INIS)

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

  5. Technical quality of root canal fillings performed in a dental school and the associated retention of root-filled teeth: a clinical follow-up study over a 5-year period.

    LENUS (Irish Health Repository)

    Burke, F M

    2009-07-01

    The aim of this study was to examine the technical quality of root canal fillings performed in a dental school and to investigate the associated effect on the survival\\/retention of root-filled teeth. A review of case notes of patients who had root canal treatment performed in the department of Restorative Dentistry, University Dental School and Hospital, Cork, Ireland was carried out. The technical quality of the root canal filling was described according to its relationship with the radiographic apex on a post-treatment radiograph. Tooth status at review was defined as \\'tooth present\\' or \\'tooth absent\\' based on the presence or absence of the root-filled tooth recorded in the treatment records at a review appointment following placement of the root canal filling. One hundred and forty-eight teeth (129 patients) were considered. Of these, 69.6% (n = 103) were of acceptable technical quality, 23.6% (n = 35) were under-extended, and 6.8% (n = 10) were overextended. An increased number of intra-treatment radiographs to confirm the relationship of the canal preparation to the radiographic apex and operator experience were significant predictors of adequate root canal fillings (P < 0.05). Eighty-three per cent (n = 123) of teeth were present at a review appointment held an average of 40 months following completion of treatment (12-60 months). The technical quality of the root canal filling was the only significant factor in predicting tooth survival (P < 0.05), while the presence of pre-treatment periapical pathology had no significant effect on survival of the root-filled tooth. Determination and maintenance of the working length of the canal system is an important feature in producing good quality root canal fillings, which in turn, is associated with increased likelihood of survival\\/retention of root-filled teeth.

  6. Discussion and Reflection on Several Core Issues in the Grand Canal Heritage Conservation Planning Under the Background of Application for World Heritage

    Science.gov (United States)

    Yao, D.; Dai, D. S.; Tang, Y. Z.; Zhu, G. Y.; Chen, X.

    2015-08-01

    At the turn of the century, a series of new heritage concepts have appeared in the area of international cultural heritage protection, such as cultural landscape, cultural route, heritage corridor, heritage canal, which presents the development of people's recognition of cultural heritage. According to The Operational Guidelines for the Implementation of the World Heritage Convention, management planning must be contained in the material used to apply for world heritage. The State Administration of Cultural Heritage designed the mission and work schedule of China's Grand Canal conservation planning in 2008. This research will introduce the working system of China's Grand Canal conservation planning on three levels: city, province and nation. It will also summarize the characteristics of the core technologies in China's Grand Canal conservation planning, including key issues like the identification of the core characteristic of China's Grand Canal, value assessment and determination of the protection scope. Through reviewing, thinking and analyzing the previous accomplishments, the research will offer some advices for the similar world heritage conservation planning after.

  7. 改良耳道皮瓣耳道口扩大成形的研究%Research of modified skin flap of external canal in auditory canal shaping to enlarge

    Institute of Scientific and Technical Information of China (English)

    王东; 李同丽; 陈煜; 李欣

    2012-01-01

    Objective:To investigate the new method of modified skin flap of external canal in auditory canal shaping to enlarge at radical mastoidectomy in endaural incision. MethodsFrom 1999 to 2009,412 patients with 428 ears in operation were randomly divided into two groups. Patients underwent open mastoidectomy and some patients were performed concurrent tympanoplasty. A group (control group)were operated in traditional skin flap of external canal,B group is modified group. Bleed and effusion from the wound surface,the time of dry ear and the change of diameter of extermal acoustic meatus after one year were observed after the surgeries and deal the results with SPSS. Resell: The difference had statistical significance in bleed and effusion from the wound surf ace, the time of dry ear and the shrink of external acoustic meatus in 12 months among two groups. Conclnsion; Modified skin flap of external canal in auditory canal shaping to enlarge can help to make a no-wound dehiscence by wiping out the raw surface of external acoustic meatus. It is better than traditional skin flap of external canal.%目的:探索耳内切口乳突根治术时行改良耳道皮瓣法扩大耳道口的新方法.方法:1999-2009年我科选择行开放式乳突根治术或同期行鼓室成形术的病例421例(428耳),随机分为A、B组.A组为对照组,行传统耳道皮瓣法;B组为改良组,行改良的耳道皮瓣法.所有病例观察术后的出血、渗出情况,干耳时间及1年后耳道口的变化情况.结果:统计学分析表明,改良组较对照组在术后出血、渗出、干耳时间及耳道口缩小方面均差异有统计学意义.结论:改良耳道皮瓣法扩大耳道口成形后,消灭了外耳道的创面,形成了无创面的耳道口,比传统皮瓣法有较多优点.

  8. Nonneoplastic enhancement of internal auditory canal contents mimicking intracanalicular acoustic neuroma on MR images

    International Nuclear Information System (INIS)

    The authors present five patients with inflammation of facial and/or vestibulocochlear nerves that showed enhancement of structures in the internal auditory canal. (IAC) on MR imaging that mimic intracanalicular acoustic neuroma. MR imaging findings of four patients with unilateral sensorineural hearing loss and one with acute facial paralysis were reviewed along with the operative findings. MR imaging included pre-and postcontrast T1- and T2-weighted images. Three patients who presented with unilateral sensorineural hearing loss underwent surgery for exploration and decompression of the IAC. One patient with facial paralysis showed vesicular eruption in the external auditory canal and was diagnosed as having Ramsay Hunt syndrome (herpes zosteroticus) clinically. The fifth patient is also being followed up clinically. MR imaging findings in all five cases were similar. There was focal enhancement in the lateral portion of the IAC on postcontrast T1-weighted images with minimal mass effect. The swollen and edematous nerves were noted on surgery without any evidence of neoplasm. The patients not operated on showed no progression of symptoms. The enhancement of IAC contents on MR imaging in patients with nonspecific neuritis or Ramsay Hunt syndrome may be difficult to differentiate from a small intracanalicular neuroma, which may have important therapeutic implications

  9. Electronic Commerce Operation of the Traditional Tourism Enterprise-- Taking Taobao Shop in Wuxi Ancient Canal for Example%传统旅游企业电子商务运营分析--以无锡古运河淘宝店铺为例

    Institute of Scientific and Technical Information of China (English)

    薛雯霞

    2014-01-01

    The rapid development of electronic commerce helps people know the related information in tourist attractions and using computers and mobiles,and pays in the Internet. Therefore,travel agency should transform marketing from of-fline promotion to online marketing. Taobao,one of the biggest e-commerce online transactions in China,provides a guarantee for its electronic commerce development. This article attempts to analyze Taobao shop’s marketing mode in the ancient canal,develops potential customers by electronic commerce mode,and increases competitive ability.%电子商务的迅猛发展,使得人们通过电脑和手机等通讯设备可以随时随地查看目标旅游景点相关信息,并在网上完成一系列交易。这一消费习惯的转变,使得传统旅游公司必须将线下推广转为线上推广。淘宝作为中国线上交易最为频繁的电子商务平台,为传统旅游企业的电子商务发展提供了可靠的保障。本文试图以淘宝古运河店铺的建立与营销为基础,探索如何通过电子商务模式抢占潜在的客户,提高公司的营销竞争力。

  10. Evolution of root canal sealers: An insight story

    Directory of Open Access Journals (Sweden)

    Sanjeev Tyagi

    2013-01-01

    Full Text Available Attainment of ideal root canal treatment comprises various essential factors such as proper instrumentation, biomechanical preparation, obturation, and ultimately depending upon the case, post-endodontic restoration. Main objective of the treatment is to get absolute rid of microbial entity and prevent any future predilection of re-infection. In order to achieve that, proper seal is required to cut down any chance of proliferation of bacteria and future occurrence of any pathology. Although gutta-percha has been the standard obturating material used in root canal treatment, it does not reinforce endodontically treated roots owing to its inability to achieve an impervious seal along the dentinal walls of the root canal. Gutta-percha does not from a monoblock even with the use of a resin-based sealer such as AH Plus because the sealer does not bind to gutta-percha. As a result, a monoblock is formed (consisting of Resilon core material, Resin sealer, bonding agent/primer, and dentin. Another reason of Resilon being a better obturating material could be that the removal of smear layer by ethylenediaminetetraacetic acid (EDTA after biomechanical preparation may have allowed the root canal filling material and root canal sealers to contact the canal wall and penetrate in the dentinal tubules, which may increase the strength of roots. New silicone-based sealers like Roekoseal automix and the most recent GuttaFlow have some affirmative results regarding solubility and biocompatibility, as compared to other sealers. Methacrylate resin-based sealers and mineral trioxide aggregate (MTA-based sealers have opened a new horizon for sealers.

  11. Absent posterior semicircular canal: HRCT feature of Waardenburg syndrome

    Directory of Open Access Journals (Sweden)

    Sandeep M Mahajan

    2012-01-01

    Full Text Available Absence of posterior semicircular canal is a rare condition, having been reported with only a few syndromes such as Waardenburg syndrome (WS, Alagellie, CHARGE, and Goldenhaar syndromes. We report a 12- year old male with bilateral absent posterior semicircular canals. These phenotypic characteristics of the patient favored the diagnosis of WS. WS is a rare autosomal dominant condition characterized by sensorineural hearing loss, in conjunction with pigmentary abnormalities and defects of the neural crest-derived tissues. The case is presented for its rarity and for its high resolution computed tomography (HRCT temporal bone findings so as to reach a precise diagnosis.

  12. Germinoma in the Internal Auditory Canal Mimicking a Vestibular Schwannoma

    Directory of Open Access Journals (Sweden)

    Rubén Martín-Hernández

    2014-01-01

    Full Text Available The appearance of a primary germinoma in the central nervous system but not on or near the midline or within the brain is exceptional. It may occur at any age; however, it is rare in patients over 50 years old. Only a handful of cases of germinomas located in the cerebellopontine angle were presented, but to our knowledge, there has been no description of an isolated germinoma in the internal auditory canal. We report a case of germinoma in the internal auditory canal in a 51-year-old man simulating the clinical and radiological characteristics of a vestibular schwannoma.

  13. Caracterización del canal radio en entornos especiales

    OpenAIRE

    Fornés Leal, Alejandro

    2015-01-01

    En el presente proyecto se estudia el canal radio en dos casos especiales de Redes Inalámbricas de Área Personal (WPAN). El primero de los casos es la transmisión durante un incendio indoor. El objetivo es caracterizar el canal en la banda UWB (Banda Ultra-Ancha, por sus siglas en inglés) para averiguar si se producen pérdidas adicionales a las de espacio libre debidas al fuego, y con ello conocer en una primera aproximación si la implantación de nuevos sistemas para mejorar la seguridad de l...

  14. Semicircular canals circumvent Brownian Motion overload of mechanoreceptor hair cells

    DEFF Research Database (Denmark)

    Muller, Mees; Heeck, Kier; Elemans, Coen P H

    2016-01-01

    Vertebrate semicircular canals (SCC) first appeared in the vertebrates (i.e. ancestral fish) over 600 million years ago. In SCC the principal mechanoreceptors are hair cells, which as compared to cochlear hair cells are distinctly longer (70 vs. 7 μm), 10 times more compliant to bending (44 vs. 500...... to circumvent Brownian motion overload at the hair bundles. We suggest that the selective advantage of detecting such low frequency stimuli may have favoured the evolution of large guiding structures such as semicircular canals and otoliths to overcome Brownian Motion noise at the level of the mechanoreceptors...

  15. Acoustic impedances of ear canals measured by impedance tube

    DEFF Research Database (Denmark)

    Ciric, Dejan; Hammershøi, Dorte

    2007-01-01

    During hearing sensitivity tests, the sound field is commonly generated by an earphone placed on a subject ear. One of the factors that can affect the sound transmission in the ear is the acoustic impedance of the ear canal. Its importance is related to the contribution of other elements involved...... locations in an impedance tube. The end of the tube representing the measurement plane is placed at the ear canal entrance. Thus, the impedance seen from the entrance inward is measured on 25 subjects. Most subjects participated in the previous measurement of the ratio between the pressures at the open...

  16. Evaluation of pre-fabricated root canal posts.

    Science.gov (United States)

    Hew, Y S; Purton, D G; Love, R M

    2001-03-01

    In this in vitro study, properties of a titanium alloy post recently introduced to the market (IntegraPost), were compared with those of a clinically proven stainless steel post (ParaPost). The IntegraPost has a unique, perforated, spherical head and a microknurled shank surface. The posts were tested for rigidity, for retention within the root canals of extracted teeth and for ability to retain composite resin cores. The two post types exhibited similar properties in core and root canal retention, however, the IntegraPost was significantly less rigid than the ParaPost.

  17. Optodynamic Phenomena During Laser-Activated Irrigation Within Root Canals

    Science.gov (United States)

    Lukač, Nejc; Gregorčič, Peter; Jezeršek, Matija

    2016-07-01

    Laser-activated irrigation is a powerful endodontic treatment for smear layer, bacteria, and debris removal from the root canal. In this study, we use shadow photography and the laser-beam-transmission probe to examine the dynamics of laser-induced vapor bubbles inside a root canal model and compare ultrasonic needle irrigation to the laser method. Results confirm important phenomenological differences in the two endodontic methods with the laser method resulting in much deeper irrigation. Observations of simulated debris particles show liquid vorticity effects which in our opinion represents the major cleaning mechanism.

  18. A Guyon's canal ganglion presenting as occupational overuse syndrome: A case report.

    LENUS (Irish Health Repository)

    Chan, Jeffrey C Y

    2008-01-01

    Occupational overuse syndrome (OOS) can present as Guyon\\'s canal syndrome in computer keyboard users. We report a case of Guyon\\'s canal syndrome caused by a ganglion in a computer user that was misdiagnosed as OOS.

  19. News of CanalUGR tracked on Google News, Yahoo! News and Bing News

    OpenAIRE

    Herrero-Solana, V??ctor; Arboledas M??rquez, Luis; Leger??n-??lvarez, Elisa

    2013-01-01

    Dataset contains 613 news of CanalUGR (University of Granada Communication Office) tracked on the main online news aggregators (Google News, Yahoo! News and Bing News). We include: number in CanalUGR, media, country, type.

  20. Root Canal Morphology of Mandibular First Permanent Molars in an Indian Population

    Directory of Open Access Journals (Sweden)

    Hemant Ramesh Chourasia

    2012-01-01

    Full Text Available An in vitro study was performed to determine the number of roots, root canals per tooth, root canal configurations, and frequency of isthmi and apical deltas in mandibular first permanent molars in an Indian population. Hundred and fifty mandibular first permanent molars were collected and subjected to clearing technique. The cleared teeth were examined in a stereomicroscope under 7.5x magnifications. The canal configurations were categorized using Vertucci's classification. Overall 94.6% of the mandibular first molars had two roots, and 5.3% had extradistal roots (distolingual root. In addition, 64% of the specimens had three root canals, and 36% had four root canals. The most common canal configurations of mesial and distal roots were Vertucci type IV (54% and type I (65.3%, respectively. Clinician should be aware of the complex root canal morphology of mandibular first molars among the Indian population before and during the root canal treatment.

  1. Endodontic Management of Mandibular First Molar with Middle Distal Canal: A Case Report

    Directory of Open Access Journals (Sweden)

    Vijay Reddy Venumuddala

    2012-01-01

    Full Text Available The knowledge of variations in root canal morphology is critical for a successful endodontic treatment. This article presents the endodontic management of a unique case of mandibular molar with middle distal canal which is quite uncommon.

  2. Development of the lateral line canal system through a bone remodeling process in zebrafish.

    Science.gov (United States)

    Wada, Hironori; Iwasaki, Miki; Kawakami, Koichi

    2014-08-01

    The lateral line system of teleost fish is composed of mechanosensory receptors (neuromasts), comprising superficial receptors and others embedded in canals running under the skin. Canal diameter and size of the canal neuromasts are correlated with increasing body size, thus providing a very simple system to investigate mechanisms underlying the coordination between organ growth and body size. Here, we examine the development of the trunk lateral line canal system in zebrafish. We demonstrated that trunk canals originate from scales through a bone remodeling process, which we suggest is essential for the normal growth of canals and canal neuromasts. Moreover, we found that lateral line cells are required for the formation of canals, suggesting the existence of mutual interactions between the sensory system and surrounding connective tissues.

  3. AFSC/ABL: Lynn Canal Overwinter Acoustic Survey, 2004-2005

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The acoustic trawl database for Lynn Canals echo-trawl survey was conducted from 2001 to 2004 throughout southern Lynn Canal in southeast Alaska. Acoustic surveys...

  4. Four cuspal maxillary second premolar with single root and three root canals: Case report

    Directory of Open Access Journals (Sweden)

    Parul Bansal

    2016-01-01

    Full Text Available Traditional configuration of maxillary second premolars has been described to have two cusps, one root and one or two root canals. The endodontic literature reports considerable anatomic aberrations in the root canal morphology of maxillary second premolar but the literature available on the variation in cuspal anatomy and its relationship to the root canal anatomy is sparse. The purpose of this clinical report was to describe the root and root canal configuration of a maxillary second premolar with four cusps.

  5. Four cuspal maxillary second premolar with single root and three root canals: Case report.

    Science.gov (United States)

    Bansal, Parul; Nikhil, Vineeta; Goyal, Ayush; Singh, Ritu

    2016-01-01

    Traditional configuration of maxillary second premolars has been described to have two cusps, one root and one or two root canals. The endodontic literature reports considerable anatomic aberrations in the root canal morphology of maxillary second premolar but the literature available on the variation in cuspal anatomy and its relationship to the root canal anatomy is sparse. The purpose of this clinical report was to describe the root and root canal configuration of a maxillary second premolar with four cusps. PMID:27563190

  6. Treatment of Two Canals in All Mandibular Incisor Teeth in the Same Patient

    Directory of Open Access Journals (Sweden)

    Vandana B. Kokane

    2014-01-01

    Full Text Available The main reason for unfavourable outcome in endodontic treatment of mandibular incisor is the inability to detect the presence of second canal. Pain even after extirpation of complete pulp tissue from root canal of vital teeth is the main indication of hidden canals. The present case report is also on pain because of another neglected canal in all mandibular incisors in the same patient.

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

    Directory of Open Access Journals (Sweden)

    Mohanavelu Deepalakshmi

    2012-01-01

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

  8. 两种根管充填剂疼痛反应临床观察%Clinical Study of Pain Reaction to Two Kinds of Root Canal Filler

    Institute of Scientific and Technical Information of China (English)

    魏达

    2012-01-01

    目的:比较Cortisomol根充糊剂和氧化锌丁香油根管充填剂进行根管充填术后疼痛反应发病率的情况.方法:对198颗惠牙分别使用Cortisomol根充糊剂和氧化锌根管充填剂进行根管充填,观察其术后反应情况.结果:Cortisomol根充糊剂组术后疼痛反应的发病率显著低于氧化锌根管充填剂组(P<0.01).结论:使用Cortisomol根充糊剂是一种比较理想的根管充填剂,可以减少病人痛苦.%Objective: To compare the incidence of pain reaction after root canal filling operation by filling Cortisomol Paste and Zinc Clove Oil Paste. Method: Use Cortisomol Paste and Zinc Clove Oil Paste to do the root canal filling operation on 198 sick teeth, respectively.Result: The incidence of pain reaction after root canal filling operation by filling Cortisomol Paste was obviously lower than the Zinc Clove Oil Paste ( P<0.01 ) . Conclusion : Relatively speaking,Cortisomol Paste is an ideal root canal filling paste since dentists can alleviate the sufferings of the patients by using it.

  9. DERMOID CYST OF INGUINAL CANAL MASQUERADING AS IRREDUCIBLE INGUINAL HERNIA: A CASE REPORT WITH RE VIEW OF LITERATURE

    Directory of Open Access Journals (Sweden)

    Chandrakant R

    2013-03-01

    Full Text Available ABSTRACT: INTRODUCTION : Dermoid cysts are common developmental anomalies o ccurring along embryonic fusion lines. Occurrence of this in inguinal region is rare and imposes diagnostic challenge as it confuses the clinician a s irreducible inguinal hernia. CASE REPORT : Fifty years male patient presented with irreducible l eft inguinal hernia. Exploration of the left inguinal canal revealed a cyst (7cm x 5cm in the f loor of the inguinal canal separated from the cord structures. The cyst was opened and foul smelli ng muddy paste like material came out. Cyst was completely excised. The histopathology was consistent with a dermoid cyst. The patient is doing well at five month follow up. CONCLUSION : Inguinal dermoid cyst mimicking irreducible hernia is rare but possible entity. If s uch cyst is encountered during hernia operation, complete excision is to be contemplated.

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  13. A central incisor with 4 independent root canals: a case report

    NARCIS (Netherlands)

    C. Aznar Portoles; A.T. Moinzadeh; H. Shemesh

    2015-01-01

    The maxillary central incisor is the tooth with the least anatomic variations. Despite the fact that several studies have reported a prevalence of 100% for the presence of a single canal, root canal aberrations of maxillary central incisors with up to 3 canals have also been reported. Such cases rep

  14. DOWNSTREAM-WATER-LEVEL CONTROL TEST RESULTS ON THE WM LATERAL CANAL

    Science.gov (United States)

    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...

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

    Directory of Open Access Journals (Sweden)

    Bonny Paul

    2014-01-01

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

  16. The ability of optical coherence tomography to characterize the root canal walls

    NARCIS (Netherlands)

    Shemesh, Hagay; Van Soest, Gijs; Wu, Min-Kai; Van der Sluis, Lucas W. M.; Wesselink, Paul R.

    2007-01-01

    A detailed understanding of the complexity of root canal systems is imperative to ensure successful root canal therapy. The aim of this study was to evaluate the ability of an optical coherence tomography (OCT) system in imaging root canal walls after endodontic preparation and to correlate these im

  17. A new strategy in root canal therapy: there is a lot going on in endodontic disinfection

    NARCIS (Netherlands)

    S.V. van der Waal

    2015-01-01

    Apical periodontitis (AP) is the inflammatory response in the surrounding tissues at the root tip of a tooth to a microbial infection of the root canal system inside the tooth. AP can only resolve after thorough root canal disinfection. However at present, state-of-the-art root canal treatment does n

  18. Role of the confinement of a root canal on jet impingement during endodontic irrigation

    NARCIS (Netherlands)

    Verhaagen, B.; Boutsioukis, C.; Heijnen, G. L.; van der Sluis, L. W. M.; Versluis, M.

    2012-01-01

    During a root canal treatment the root canal is irrigated with an antimicrobial fluid, commonly performed with a needle and a syringe. Irrigation of a root canal with two different types of needles can be modeled as an impinging axisymmetric or non-axisymmetric jet. These jets are investigated exper

  19. Surgical Indications of Exploring Optic Canal and Visual Prognostic Factors in Neurosurgical Treatment of Tuberculum Sellae Meningiomas

    Institute of Scientific and Technical Information of China (English)

    Hao-Cheng Liu; E Qiu; Jia-Liang Zhang; Jun Kang; Yong Li; Yong Li; Li-Bin Jiang

    2015-01-01

    Background:Tuberculum sellae meningiomas (TSMs) present a special symptom because of the adherence and compression to the optic nerve,optic artery,and the chiasm.A significant number of patients with TSMs appear visual deficits.This study aimed to investigate the surgical indications of exploring the optic canal and visual prognostic factors in the neurosurgical treatment of TSMs.Methods:Totally 21 patients with TSM,who were operated from September 2007 to August 2011 in the Department of Neurosurgery,Tongren Hospital were enrolled in this study.Results of orbital computed tomography (CT) and magnetic resonance imaging (MRI),visual acuity,Goldmann visual field test,orbital color Doppler flow imaging (CDI) test in these patients were retrospectively analyzed.Results:Visual deficit and optic canal involvement (OCI) were detected in all the 21 patients.Fourteen patients had bone proliferation within the area of the optic canal.After the operation,visual outcomes were improved in 13 patients,unchanged in 7 patients,and deteriorated in 1 patient.All the 21 patients performed orbital CDI test preoperatively,the results showed that if the peak systolic velocity (PSV) of central retinal artery (CRA) value was ≤8 crr/s,the visual outcome would be better.Conclusions:The surgical indications of exploring optic canal in TSM cases included:(1) The neuroimaging evidences ofOCI (CT and/ or MRI);(2) PSV of CRA in orbital CDI test was ≤8 crr/s;(3) visual acuity was below 0.1;(4) visual field deficit.The PSV of CRA in CDI test could be a prognostic factor for visual outcomes of TSMs.

  20. Exposure and direct stimulation of the semicircular canal cupula.

    Science.gov (United States)

    Suzuki, M; Harada, Y

    1985-01-01

    The ampullary wall of the posterior semicircular canal was isolated from the frog, cut and the cupula exposed in frog Ringer's solution. The cupula was stimulated by depression with a fine glass micropipette. Three points on the cupula were selected for depression: point A, the lowest point on the midline of the cupula surface on the utricular side; point B, the uppermost on the midline of the same surface; and point C, in the middle of the lateral surface of the cupula. Depression at points A and B was toward the canal, whereas depression at point C was toward the centre of the cupula. The amount of depression was controlled by a micromanipulator. At point A, the minimum depression facilitating the posterior canal action potential was 1 micron; at point B, a greater amount of depression was needed to produce the action potential. Even a large amount of depression at point C resulted in only a small action potential, possibly because the direction of the sensory cell polarity is along the long axis of the canal.

  1. The spiral ganglion and Rosenthal's canal in beluga whales.

    Science.gov (United States)

    Sensor, Jennifer D; Suydam, Robert; George, John C; Liberman, M C; Lovano, Denise; Rhaganti, Mary Ann; Usip, Sharon; Vinyard, Christopher J; Thewissen, J G M

    2015-12-01

    With the increase of human activity and corresponding increase in anthropogenic sounds in marine waters of the Arctic, it is necessary to understand its effect on the hearing of marine wildlife. We have conducted a baseline study on the spiral ganglion and Rosenthal's canal of the cochlea in beluga whales (Delphinapterus leucas) as an initial assessment of auditory anatomy and health. We present morphometric data on the length of the cochlea, number of whorls, neuron densities along its length, Rosenthal's canal length, and cross-sectional area, and show some histological results. In belugas, Rosenthal's canal is not a cylinder of equal cross-sectional area, but its cross-section is greatest near the apex of the basal whorl. We found systematic variation in the numbers of neurons along the length of the spiral ganglion, indicating that neurons are not dispersed evenly in Rosenthal's canal. These results provide data on functionally important structural parameters of the beluga ear. We observed no signs of acoustic trauma in our sample of beluga whales.

  2. [The use of ultrasonic files in canal preparation].

    Science.gov (United States)

    Calas, P; Terrie, B

    1990-01-01

    The continuous high volume of irrigating solution delivered by the ultrasonic system facilitates the root canal debridement. An excellent cleaning of dentin wall is obtained even on surfaces unreached by the mechanical instrumentation. In order to obtain an efficacious preparation, the use of ultrasonic files were combined with instrumentation. This new technique is described in this article. PMID:2168733

  3. Shape and Deformation Analysis of the Human Ear Canal

    DEFF Research Database (Denmark)

    Darkner, Sune

    This thesis presents work on the analysis of the dynamic behavior of the human ear canal. The work is based on two studies designed during the project, a pilot study with 30 normal hearing subjects and a main study with 42 hearing impaired subjects, all hearing-aid users. The main focus is on the......This thesis presents work on the analysis of the dynamic behavior of the human ear canal. The work is based on two studies designed during the project, a pilot study with 30 normal hearing subjects and a main study with 42 hearing impaired subjects, all hearing-aid users. The main focus...... is on the extraction and analysis of the shape and deformation of the ear canal due to movements of the mandible, leaning over, and turning of the head. Methods for surface registration with focus on non-rigid registration are presented, as well as a wide range of statistical methods used for analyzing the shapes...... and deformation fields. The results show that the ear canal changes shape significantly in all subjects and that the deformation is more complicated than previously described in the literature. It is shown that the deformation at specific locations in the ear is significantly correlated to comfort issues reported...

  4. Statistical Surface Recovery: A Study on Ear Canals

    DEFF Research Database (Denmark)

    Jensen, Rasmus Ramsbøl; Olesen, Oline Vinter; Paulsen, Rasmus Reinhold;

    2012-01-01

    that are Procrustes aligned. The average shape and point covariances can be estimated from this set. It is shown how missing data in a new given shape can be predicted using the learned statistics. The method is evaluated on a data set of 29 scans of ear canal impressions. By using a leave-one-out approach we...

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

    DEFF Research Database (Denmark)

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

    2013-01-01

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

  6. Quality improvement of photopolimerizable-cement root canal obturation

    Science.gov (United States)

    Lupato Conrado, Luis A.; Frois, Iris M.; Amaro Zangaro, Renato; Munin, Egberto; Kuranaga, Carlos; Dias da Silva, Marcos; do Carmo de Andrade Nono, Maria; Cerquiera Rezende, Mirabel

    2003-06-01

    The sealing cements commonly used for endodontic applications are of the type cured through chemical reactions. During the polymerization process, mechanical contractions are not uncommon, leading to a non-perfect sealing. Photopolymerizable cements usually presents superior performance as compared to those chemically activated. However, difficulties in carrying the light to difficult-to-reach regions like the dental apex preclude those material of being accepted in the dental office routine. This work reports on a novel technique which allow the light curing of photopolymerizable cements in endodontic applications. A special light guide had been developed to allow the curing light to reach and polymerize the sealing cement in the apex region. The technique was tested by using single-root human teeth with normal canal morphology. The Ultradent EndoREZ root canal sealer and a resin-based photopolymerizable filler specially developed for the current application had been used. The cone-shaped light guide was introduced into treated canals filled with the photopolymerizable material, up to the apical region. Light from an argon laser was launched onto the light guide for polymerization. All test samples were immersed in methylene-blue solution for microleakage testing. All samples treated with the self-polymerizable material presented dye penetration to some extent. No sample within the group which had the filling material polymerized by using the light guide presented dye penetration through the canal wall.

  7. [The use of ultrasonic files in canal preparation].

    Science.gov (United States)

    Calas, P; Terrie, B

    1990-01-01

    The continuous high volume of irrigating solution delivered by the ultrasonic system facilitates the root canal debridement. An excellent cleaning of dentin wall is obtained even on surfaces unreached by the mechanical instrumentation. In order to obtain an efficacious preparation, the use of ultrasonic files were combined with instrumentation. This new technique is described in this article.

  8. Semicircular canals circumvent brownian motion overload of mechanoreceptor hair cells

    NARCIS (Netherlands)

    Muller, Mees; Heeck, Kier; Elemans, Coen P.H.

    2016-01-01

    Vertebrate semicircular canals (SCC) first appeared in the vertebrates (i.e. ancestral fish) over 600 million years ago. In SCC the principal mechanoreceptors are hair cells, which as

    compared to cochlear hair cells are distinctly longer (70 vs. 7 μm), 10 times more compliant to bending (4

  9. Anatomo-radiological study of the Superior Semicircular Canal Dehiscence

    Energy Technology Data Exchange (ETDEWEB)

    Crovetto, M., E-mail: macdlt@telefonica.net [Otolaryngology Department, Hospital de Basurto, University of the Basque Country, Avenida de Montevideo 18, Bilbao 48013, Vizcaya (Spain); Whyte, J., E-mail: jwhite@unizar.es [Faculty of Medicine, Department of Human Anatomy and Histology, University of Zaragoza, C/Domingo Mirall s/n, Zaragoza (Spain); Rodriguez, O.M., E-mail: OLIVIAMARIA.RODRIGUEZSANVICENT@osakidetza.net [Hospital de Cruces, Baracaldo, Vizcaya (Spain); Lecumberri, I., E-mail: INIGO.LECUMBERRICORTES@osakidetza.net [Hospital de Basurto, Avenida Montevideo 18, Bilbao 498013 (Spain); Martinez, C., E-mail: claudiorayosx@yahoo.es [Hospital General de la Defensa, Via Iberica s/n Zaragoza (Spain); Elexpuru, J., E-mail: jelexpuru@mac.com [Hospital de Basurto, Avenida de Montevideo 18, Bilbao 48013, Vizcaya (Spain)

    2010-11-15

    Introduction: The main purpose of this study is to determine the radiological incidence of Superior (SSCD) and Posterior Semicircular Canal Dehiscence (PSCD) and to compare radiologic SSCD to the incidence of this condition on cadaver specimen. We have also analysed the relation between the ossification state of the semicircular canals and the degree of mastoid pneumatization and integrity of Tegmen Tympani. Material and methods: Temporal bones have been investigated by means of CT scan on patients and direct observation on cadaver specimen, respectively. Results: 604 ears and 160 cadaver temporal bones have been investigated by means of CT scan and direct observation, respectively. 3.6% and 0.3% of the studied ears had SSCD and PSCD, respectively, on CT scan. Only 0.6% of the cadaver specimen ears did have anatomical SSCD. Degree of pneumatization of the mastoid bone is related to the mean thickness of bone overlying the Superior and Posterior Semicircular Canal. Radiological absence of Tegmen Tympani is more frequent in ears that also have radiologic SSCD. Conclusion: CT scanning gives higher incidence figures of SSCD than anatomical studies, 3.6% vs. 0.6%. We also found a 0.6% incidence of radiological PSCD in the studied ears. There is a direct relation between the degree of ossification of Superior and Posterior Semicircular Canal and certain temporal bone anatomic features: temporal bone pneumatization and absence/presence of Tegmen Tympani or Antri.

  10. Bacteriologic results from 4,000 root canal cultures

    NARCIS (Netherlands)

    Winkler, K.C.; Amerongen, J. van

    1959-01-01

    The bacteriologic results from more than 4,000 root canal cultures are discussed. Streptococci form 61 per cent of the isolated organisms. Among these, the group of hemolytic, indifferent, and indifferent anaerobic streptococci, mainly belonging to serologic groups F, G, and C, seem the most serious

  11. Mimamata and Love Canal: A Pollution Tale of Two Cities.

    Science.gov (United States)

    Williams, Mary Louise

    1993-01-01

    Presents a lesson plan about case studies of the environmental disasters of Minamata, Japan and Love Canal, New York. Compares how the legal cases were handled in two constitutional democracies. Provides six handouts that include maps, role descriptions for simulations, and student readings. (CFR)

  12. Lightlike Hypersurfaces and Canal Hypersurfaces of Lorentzian Surfaces

    Directory of Open Access Journals (Sweden)

    Jianguo Sun

    2014-01-01

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

  13. Garigliano Nuclear Power Plant, Italy: Decontamination and Rearranging of Reactor Canal and Spent Fuel Pool

    International Nuclear Information System (INIS)

    Garigliano nuclear power plant was a 506 MW(th), first generation, dual cycle BWR. It started operation in 1964 and finally shut down in 1978, following the discovery of serious damage to a secondary steam generator. This section describes decontamination activities carried out in 1991–1993 in preparation for safe enclosure of Garigliano reactor building.1 Activities were carried out after completion of spent fuel transport off-site (1985–1987). A schematic of the spent fuel pool and adjacent areas is provided. Decontamination activities included the following: (a) Agitation and resuspension of pool sediments using water jets and water filtration. (b) Lowering of water level and parallel decontamination of pool walls with high pressure water jets of approximately 700 kg/cm2. (c) Removal, decontamination and interim storage on gangways of equipment located on the pool south-east wall. (d) Removal, decontamination and storage of the fuel transport container platform. (e) Removal of four fuel racks to their pool wall bearings, decontamination and transfer to the fresh fuel room. (f) Decontamination of the vessel head platform, removal from the reactor canal, brushing and coating to allow preservation and fixing of loose contamination. Eventually, this component was placed back in the reactor canal. (g) Construction in the reactor canal of an interim structure supporting fuel racks. At the completion of the work, this structure was dismounted, decontaminated and removed. (h) Removal of fuel racks (five at a time) to their pool wall bearings, decontamination and interim storage in the reactor canal. (i) Gradual lowering of the pool water level to some 50 cm from the pool floor and parallel decontamination of fixed structures and walls. (j) Discovery by visual inspection and radiological checks, of activated components on the floor of the pool. Retrieval of all this material, segmentation as needed, temporary storage in containers and later transfer to the high

  14. In vitro comparison of passive and continuous ultrasonic irrigation in curved root canals

    Science.gov (United States)

    Castelo-Baz, Pablo; Varela-Patiño, Purificación; Cantatore, Giuseppe; Domínguez-Perez, Ana; Ruíz-Piñón, Manuel; Martín-Biedma, Benjamín

    2016-01-01

    Background The efficacy of endodontic irrigation procedures can be compromised by the complexity of the root canal system. Delivering irrigants to the apical third of curved canals presents a particular challenge to endodontists. This study compared the effects of two ultrasonic irrigation techniques on the penetration of sodium hypochlorite into the main canal and simulated lateral canals of curved roots in extracted teeth. Material and Methods Two sets of simulated lateral canals were created at 2, 4, and 6 mm from the working length in 60 single-rooted teeth (6 canals/tooth, n = 360 canals). The teeth were randomly divided into three experimental irrigation groups: group 1 (n = 20), positive pressure irrigation (PPI); group 2 (n = 20), passive ultrasonic irrigation (PUI); and group 3 (n = 20), continuous ultrasonic irrigation (CUI). To assess the irrigation solution penetration, 20% Chinese ink (Sanford Rotring GmbH, Hamburg, Germany) was added to a 5% sodium hypochlorite solution and delivered into the curved root canals. The penetration of contrast solution into the simulated lateral canals was scored by counting the number of lateral canals (0-2) penetrated to at least 50% of the total length. Results The CUI group showed significantly higher (P irrigant penetration into the lateral canals and into the apical third of the main canals. The PPI group showed significantly lower sodium hypochlorite penetration (P irrigant penetration was observed in the PUI group than the PPI group. Conclusions Using CUI as the final rinse significantly increased the penetration of irrigant solution into the simulated lateral canals and apical third of curved roots. Key words:Continuous ultrasonic irrigation, curved root canals, passive ultrasonic irrigation, positive pressure irrigation, root canal irrigation.

  15. Ultrasound-guided continuous adductor canal block for analgesia after total knee replacement

    Institute of Scientific and Technical Information of China (English)

    Zhang Wei; Hu Yan; Tao Yan; Liu Xuebing; Wang Geng

    2014-01-01

    Background There are several methods for postoperative analgesia for knee surgery.The commonly utilized method is multimodal analgesia based on continuous femoral nerve block.The aim of this study was to investigate the application of continuous adductor canal block for analgesia after total knee replacement and compare this method with continuous femoral nerve block.Methods Sixty patients scheduled for total knee replacement from June 2013 to March 2014 were randomly divided into a femoral group and an adductor group.Catheters were placed under the guidance of nerve stimulation in the femoral group and under the guidance of ultrasound in the adductor group.Operations were performed under combined spinal and epidural anesthesia.After the operations,0.2% ropivacaine was given at a speed of 5 ml/h through catheters in all patients.Visual analogue scale (VAS) pain scores at rest and while moving were noted at 4,24,and 48 hours after the operation,and quadriceps strength was also assessed at these time-points.Secondary parameters such as doses of complementary analgesics and side effects were also recorded.Results There were no significant differences between the groups in VAS pain scores at rest or while moving,at 4,24,or 48 hours after the operation (P >0.05).At these time-points,mean quadriceps strengths in the adductor group were 3.0 (2.75-3.0),3.0 (3.0-4.0),and 4.0 (3.0-4.0),respectively,all of which were significantly stronger than the corresponding means in the femoral group,which were 2.0 (2.0-3.0),2.0 (2.0-3.0),and 3.0 (2.0-4.0),respectively (P <0.05).There were no significant differences between the groups in doses of complementary analgesics or side effects (P >0.05).X-ray images of some patients showed that local anesthetic administered into the adductor canal could diffuse upward and reach the femoral triangle.Conclusions Continuous adductor canal block with 0.2% ropivacaine could be used effectively for analgesia after total knee replacement

  16. Improving the accuracy of canal seepage detection through geospatial techniques

    Science.gov (United States)

    Arshad, Muhammad

    With climatic change, many western states in the United States are experiencing drought conditions. Numerous irrigation districts are losing significant amount of water from their canal systems due to leakage. Every year, on the average 2 million acres of prime cropland in the US is lost to soil erosion, waterlogging and salinity. Lining of canals could save enormous amount of water for irrigating crops but in present time due to soaring costs of construction and environmental mitigation, adopting such program on a large scale would be excessive. Conventional techniques of seepage detection are expensive, time consuming and labor intensive besides being not very accurate. Technological advancements in remote sensing have made it possible to investigate irrigation canals for seepage sites identification. In this research, band-9 in the [NIR] region and band-45 in the [TIR] region of an airborne MASTER data has been utilized to highlight anomalies along irrigation canal at Phoenix, Arizona. High resolution (1 to 4 meter pixels) satellite images provided by private companies for scientific research and made available by Google to the public on Google Earth is then successfully used to separate those anomalies into water activity sites, natural vegetation, and man-made structures and thereby greatly improving the seepage detection ability of airborne remote sensing. This innovative technique is much faster and cost effective as compared to conventional techniques and past airborne remote sensing techniques for verification of anomalies along irrigation canals. This technique also solves one of the long standing problems of discriminating false impression of seepage sites due to dense natural vegetation, terrain relief and low depressions of natural drainages from true water related activity sites.

  17. Forced extrusion for removal of impacted third molars close to the mandibular canal Extrusión forzada para extraer los terceros molares impactados cerca del canal mandibular

    OpenAIRE

    Dennis Flanagan DDS

    2012-01-01

    Impacted mandibular third molars can be located in close proximity to the mandibular canal. This creates a risk for the nerve or artery injury. These are contained in the canal. However, the impacted third molar can be moved coronally by orthodontic means, after removal of overlying bone, and safely extracted. The orthodontic intervention slowly moves the tooth apex away from the mandibular canal and reduces the potential for a neural injury. This method may be useful for older patients with ...

  18. Canal mandibular bífido: Presentación de una serie de casos Bifid mandibular canal: Case series report

    Directory of Open Access Journals (Sweden)

    C.L. Guzmán Zuluaga

    2012-04-01

    Full Text Available La ubicación y configuración de las variaciones del canal mandibular son relevantes en diferentes procedimientos clínicos de la mandíbula. En esta serie de casos un radiólogo evaluó el recorrido del canal mandibular identificando la presencia y tipos de canales bífidos. Se observaron cuatro pacientes con canal mandibular bífido tipo retromolar y tres sujetos con canal bífido tipo anterior sin convergencia. En otro paciente se encontraron forámenes dentarios bífidos bilaterales. La Tomografía Computarizada de Haz de Cono, permite la identificación oportuna de condiciones preexistentes como variaciones en la morfología natural de los canales mandibulares, previniendo efectiva y precozmente las consecuencias neurológicas que se derivan de una lesión del nervio dentario inferior.The location and configuration of the mandibular canal variations are relevant in different clinical procedures of the jaw. In this case series, a radiologist assessed the mandibular canal route identifying the presence and types of bifid canals. Four patients with type bifid mandibular retromolar canal and three subjects with type bifida anterior canal without convergence were observed. In one patient, bilateral bifid tooth foramina was found. Computed Tomography Cone Beam allows identification of preexisting conditions such as variations in the natural morphology of the mandibular canals, preventing effective and early neurological consequences arising from alveolar nerve injury.

  19. Assessment of risks of stenosis of the anal canal during a prostatic radiotherapy; evaluation des risques de stenose du canal anal lors de la radiotherapie prostatique

    Energy Technology Data Exchange (ETDEWEB)

    Almokhles, H.; Pan, Q.; Calitchi, E.; Diana, C.; Muresan, M.; Jiang, M.W.; Wu, J.F.; Wang, X.W.; Lu, H.J.; Lagrange, J.L. [Hopital Henri-Mondor, Creteil (France)

    2011-10-15

    The authors report a study which aimed at assessing the late tolerance of a prostatic irradiation at the rectum and anal canal level. They assessed the length of the rectum and of the anal canal after prostate irradiation or surgery in patients who suffered from a prostate adenocarcinoma. Data of 154 patients have been analyzed regarding the number of cases of stenosis of rectum or anal canal. They highlight the importance of the irradiated length and dose level. Short communication

  20. CANAL CONFIGURATION IN THE ROOTS OF MAXILLARY SECON D PREMOLAR: A CLINICAL STUDY

    Directory of Open Access Journals (Sweden)

    Ganesh.

    2012-10-01

    Full Text Available ABSTRACT: Modified access cavity preparation and X ray- interpre tation were used clinically to find out the additional canals in the root of maxil lary second premolars. In 85% of the case two canals were located and treated, of these 30% had t wo separate apical foramen and 50.66% had two canal, joined at the apical third in 5% of the cases, two roots with two different canals were located and in 15% of the cases, one canal was loca ted KEY WORDS: Access Preparation, Apical Foramen.

  1. Bilateral presence of two root canals in maxillary central incisors: A rare case study

    Directory of Open Access Journals (Sweden)

    M Kavitha

    2014-01-01

    Full Text Available Success in root canal treatment is achieved after thorough cleaning and shaping followed by complete obturation of the canal system. Therefore, endodontic therapy requires specific and complete knowledge of the internal and external dental anatomy, and its variations in presentation. The internal anatomy of the maxillary central incisor is well-known and usually presents one root canal system. This case report describes an endodontic treatment of traumatized both maxillary central incisors with two canal systems. Knowledge of dental anatomy is fundamental for proper endodontic practice. When root canal treatment is performed, the clinician should be aware that both external and internal anatomy may be abnormal.

  2. Bilateral presence of two root canals in maxillary central incisors: A rare case study.

    Science.gov (United States)

    Kavitha, M; Gokul, Kannan; Ramaprabha, B; Lakshmi, Amudha

    2014-04-01

    Success in root canal treatment is achieved after thorough cleaning and shaping followed by complete obturation of the canal system. Therefore, endodontic therapy requires specific and complete knowledge of the internal and external dental anatomy, and its variations in presentation. The internal anatomy of the maxillary central incisor is well-known and usually presents one root canal system. This case report describes an endodontic treatment of traumatized both maxillary central incisors with two canal systems. Knowledge of dental anatomy is fundamental for proper endodontic practice. When root canal treatment is performed, the clinician should be aware that both external and internal anatomy may be abnormal.

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

    Science.gov (United States)

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

    2015-11-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Roh, Yang Gyun; Jang, Hyun Seon; Kim, Byung Ock; Kim, Jin Soo [Chosun Univ. College of Dentistry, Gwangju (Korea, Republic of)

    2006-09-15

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

  5. Síndrome do canal de Guyon causada por cisto sinovial Guyon's canal syndrome due to a synovial cyst

    Directory of Open Access Journals (Sweden)

    Evandro Silva Ruas

    2010-01-01

    Full Text Available Apresentamos um caso de síndrome do canal de Guyon por um cisto sinovial no punho esquerdo de uma paciente do sexo feminino, de 48 anos. A paciente apresentava dor e parestesia na topografia do nervo ulnar, diminuição da força muscular e deformidade na mão esquerda. A eletroneuromiografia evidenciava compressão do nervo ulnar no nível do punho. Realizada a ressecção do cisto e descompressão do nervo no canal de Guyon. Após a cirurgia a paciente apresentou melhora da dor e da parestesia, além de aumento do trofismo muscular e correção da deformidade.The authors present a case of Guyon's canal syndrome due to a synovial cyst within the left wrist of a 48-year-old female patient. The patient reported pain and paresthesia in the topography of the ulnar nerve, loss of muscular strength and left hand deformity. Electromyography showed a compression of the ulnar nerve at the wrist level. Surgical decompression at the Guyon canal with resection of the cyst was performed. After surgery, the patient presented with improvement of pain and paresthesia, as well as an increase in muscular trophism and correction of the deformity.

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

    Science.gov (United States)

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

    2015-03-01

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

  7. 显微根管治疗的设备和技术%The equipments and technology of microscopic root canal therapy

    Institute of Scientific and Technical Information of China (English)

    侯本祥

    2015-01-01

    随着手术显微镜和显微根管治疗器械的不断改进,显微根管治疗技术已在临床广泛应用。显微镜提供良好的照明和放大的视野,使医师能更清晰地观察髓腔和根管内的形态和结构,提高操作的精确性和治疗质量。本文从显微根管治疗的设备、器械着手,对显微根管治疗技术的临床应用进行介绍。%Along with the improvement of operating microscopes and instruments,the technique of microscopic root canal treatment has been widely used. The operating microscope can offer a favorable illumination and magnification of vision,so that dentists could ob-serve the tiny morphological structure inside pulp chamber and root canal systems clearly. A good vision can greatly improve the accura-cy and quality of root canal therapy. This article introduced the clinical application of microscopic root canal treatment.

  8. Filling of simulated lateral canals using different obturation techniques: analysis through IDA digital radiograph system

    Directory of Open Access Journals (Sweden)

    Clarissa Teles Rodrigues

    2012-09-01

    Full Text Available Introduction: Lateral canals are part of the root canal system and may be related to periodontal-endodontic diseases. The filling techniques that employ thermoplasticized gutta-percha have demonstrated better results in filling lateral canals. Objective: The aim of this study was to evaluate, through digital radiographs, three techniques of root canal obturation (Lateral Condensation, Obtura II System, Tagger’s Hybrid regarding to the ability of filling artificial lateral canals. Material and methods: 30 extracted human lower premolars were used in this study. The crowns were removed and artificial laterals canals were prepared on the coronal, medium and apical thirds of the roots by using a reamer made of a K 10 file. The root canals were instrumented and obturated by the following techniques: Lateral Condensation, Obtura II System, and Tagger’s Hybrid. The teeth were radiographed with IDA digital radiograph system and the filling of the lateral canals was evaluated by scores for further statistical analysis. Results: No significant difference was found in the filling of lateral canals between Lateral Condensation and Obtura II, but a significant difference was found among these two and Tagger’s Hybrid technique. Conclusion: Tagger’s Hybrid technique promoted the highest numbers of obturated lateral canals. In the three groups, the root thirds presenting greater number of filled lateral canals were coronal and middle, regardless of the obturation technique employed.

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

    DEFF Research Database (Denmark)

    Markvart, M.; Darvann, Tron Andre; Larsen, P.;

    2012-01-01

    Markvart M, Darvann TA, Larsen P, Dalstra M, Kreiborg S, Bjørndal L. Micro‐CT analyses of apical enlargement and molar root canal complexity. International Endodontic Journal, 45, 273–281, 2012. Aim To compare the effectiveness of two rotary hybrid instrumentation techniques with focus on apical...... enlargement in molar teeth and to quantify and visualize spatial details of instrumentation efficacy in root canals of different complexity. Methodology Maxillary and mandibular molar teeth were scanned using X‐ray microcomputed tomography. Root canals were prepared using either a GT/Profile protocol or a Ra......Ce/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...

  10. Specific immunoglobulin measurements related to exposure and resistance to Schistosoma mansoni infection in Sudanese canal cleaners

    DEFF Research Database (Denmark)

    Satti, M.Z.; Lind, Peter; Vennervald, B.J.;

    1996-01-01

    The present work comprises a longitudinal study of Schistosoma mansoni infection in occupationally hyper-exposed canal cleaners in the Sudan and the influence of chemotherapy on humoral immune parameters. The study groups included chronically infected canal cleaners (n = 19), newly recruited canal...... cleaners (n = 17), normally exposed adults (n = 31), school children (n = 46) and Sudanese negative controls (n = 48). Previous studies of the same canal cleaners have demonstrated that chronically infected canal cleaners were more resistant to reinfection than newly recruited canal cleaners. ELISA...... was used to detect specific IgE and IgG subclasses in response to whole worm antigen (WWH) and soluble egg antigen (SEA) before and 3 months after praziquantel treatment in the groups of canal cleaners and before and 1 year after treatment in normally exposed adults. When intensity of infection...

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

    Directory of Open Access Journals (Sweden)

    shahin abdollahi fakhim

    2014-10-01

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

  12. 三维根管治疗术—自适应镍钛根管预备器械研究进展%Three-dimensional root canal treatment-the progress in the development of self-adjusting file

    Institute of Scientific and Technical Information of China (English)

    梁素霞

    2013-01-01

    根管预备是根管治疗术的关键步骤.镍钛根管预备器械在临床广泛应用,不断改进.最新的自适应镍钛预备器械(self-adjusting file,SAF)是由网状镍钛合金丝制成的中空锉(hollow file),具有优越的弹性、柔韧性和可压缩性,能最大限度顺应根管原有解剖形态,对扁形、椭圆形不规则根管和根管峡区进行更有效地清理.本文就SAF研究进展作一综述.%Root canal preparation is the key step of root canal treatment. Nickel-titanium endodontic files are widely used in clinic and have been continuously improved. Self-adjusting file (SAF) is the hollow file made of nickel - titanium alloy silk and with excellent elastic, flexible and compressive properties. It can adjust to the original anatomy and shape of the root canal maximally and clean the root canal efficiently, especially for the flat and oval root canals and narrow area of the root canal. SAF represents a new approach in endodontic rotary file design and operation.

  13. Root canal treatment the research status of root tip penetration effect factors%根管治疗造成根尖微渗漏影响因素的研究现状

    Institute of Scientific and Technical Information of China (English)

    张海龙; 董青; 杨光; 苏哲君; 王敬; 张兴乐

    2014-01-01

    根管治疗是现在治疗牙髓病及根尖周病的主要治疗手段。对与根尖周炎的病变,非手术治疗是首选,所以根管治疗的术后微渗漏是根管治疗成败的关键。本研究从根管预备,根管充填,根管糊剂等多方面阐述根尖微渗漏的原因,以及猜想。%Root canal therapy is now main treatment of dental pulp diseases and periapical disease treatment.Lesions of periarthritis with the apex,non-operative treatment is first selection,so the root canal therapy of postoperative micro leakage is the key to a successful root canal treatment.This study from the root canal preparation,root canal fil ing,root canal paste and so on many aspects in this paper, the causes of leakage of root tip micro and guess.

  14. Comparative evaluation of apically extruded debris during root canal preparation using ProTaper™, Hyflex™ and Waveone™ rotary systems

    Directory of Open Access Journals (Sweden)

    Jayaprada Reddy Surakanti

    2014-01-01

    Full Text Available Background and Aims: Extrusion of any debris during endodontic treatment may potentially cause post-operative complications such as flare-ups. The purpose of this in vitro study was to assess the amount of apically extruded debris during the root canal preparation using rotary and reciprocating nickel-titanium instrumentation systems. Materials and Methods: In this study, 60 human mandibular first premolars were randomly assigned to 3 groups (n = 20 teeth/group. The root canals were instrumented according to the manufacturers′ instructions using the Reciprocating single-file system WaveOne™ (Dentsply Maillefer, Ballaigues, Switzerland and full-sequence rotary Hyflex CM™ (Coltene Whaledent, Allstetten, Switzerland and ProTaper™ (Dentsply Maillefer, Ballaigues, Switzerland instruments. The canals were then irrigated using bidistilled water. The debris that was extruded apically was collected in preweighed eppendorf tubes and assessed with an electronic balance and compared. Statistical Analysis Used: The debris extrusion was compared and statistically analyzed using analysis of variance and the post hoc Student-Newman-Keuls test. Results: The WaveOne™ and ProTaper™ rotary instruments produced significantly more debris compared with Hyflex CM™ rotary instruments (P < 0.05. Conclusions: Under the conditions of this study, all systems that were used resulted in extrusion of apical debris. Full-sequence rotary instrumentation was associated with less debris extrusion compared with the use of reciprocating single-file systems.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-09-15

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

  16. Cisto aracnóideo extradural do canal espinal

    Directory of Open Access Journals (Sweden)

    Nelson Pires Ferreira

    1972-09-01

    Full Text Available É relatado o caso de um paciente que apresentava paraparesia sensitivo-motora evolutiva, datando de um ano. As radiográficas da coluna vertebral e mielografia permitiram o diagnóstico de cisto de aracnóide extradural do canal espinal de localização torácica, que foi confirmado pelo ato cirúrgico. Os autores revisam a literatura assinalando 76 casos já publicados. São comentadas a incidência do processo patológico nos diversos grupos etários, sua localização ao longo do canal raqueano, a evolução do quadro clínico, a etiología e a fisiopatologia do crescimento do cisto, o diagnóstico, a terapêutica e o prognóstico.

  17. Molecular mechanisms of canalization: Hsp90 and beyond

    Indian Academy of Sciences (India)

    Neeraj Salathia; Christine Queitsch

    2007-04-01

    The Hsp90 chaperone machine facilitates the maturation of a diverse set of ‘client’ proteins. Many of these Hsp90 clients are essential nodes in signal transduction pathways and regulatory circuits, accounting for the important role Hsp90 plays in organismal development and responses to the environment. Recent findings suggest a broader impact of the chaperone on phenotype: fully functional Hsp90 canalizes wild-type phenotypes by suppressing underlying genetic and epigenetic variation. This variation can be expressed upon challenging the Hsp90 machinery by environmental stress, genetic or pharmaceutical targeting of Hsp90. The existence of Hsp90-buffered genetic and epigenetic variation together with plausible release mechanisms has wide-ranging implication for phenotype and possibly evolutionary processes. Here, we discuss the role of Hsp90 in canalization and organismal plasticity, and highlight important questions for future experimental inquiry.

  18. A comparison of methods used in root canal sealability studies

    Energy Technology Data Exchange (ETDEWEB)

    Matloff, I.R.; Jensen, J.R.; Singer, L.; Tabibi, A.

    1982-02-01

    The purpose of the study was to compare several methods that have been used to assess marginal leakage of root canal fillings. Sixty-three extracted, single-rooted teeth were instrumented and filled in a standardized manner. Teeth were randomly divided into groups of twenty and exposed to solutions containing methylene blue dye, calcium-45, carbon-14-labeled urea, and iodine-125-labeled albumin for 48 hours to compare the degree of leakage indicated by each technique. Methylene blue dye was found to penetrate farther up the canal than any of the isotope tracers. Carbon-14-labeled urea penetrated farther than the calcium-45- or iodine-125-labeled albumin. The mean volume of solution penetrating the teeth was exceedingly small (0.0011 ml) and probably unimportant physiologically.

  19. A comparison of methods used in root canal sealability studies

    International Nuclear Information System (INIS)

    The purpose of the study was to compare several methods that have been used to assess marginal leakage of root canal fillings. Sixty-three extracted, single-rooted teeth were instrumented and filled in a standardized manner. Teeth were randomly divided into groups of twenty and exposed to solutions containing methylene blue dye, calcium-45, carbon-14-labeled urea, and iodine-125-labeled albumin for 48 hours to compare the degree of leakage indicated by each technique. Methylene blue dye was found to penetrate farther up the canal than any of the isotope tracers. Carbon-14-labeled urea penetrated farther than the calcium-45- or iodine-125-labeled albumin. The mean volume of solution penetrating the teeth was exceedingly small (0.0011 ml) and probably unimportant physiologically

  20. 3D root canal modeling for advanced endodontic treatment

    Science.gov (United States)

    Hong, Shane Y.; Dong, Janet

    2002-06-01

    More than 14 million teeth receive endodontic (root canal) treatment annually. Before a clinician's inspection and diagnosis, destructive access preparation by removing teeth crown and dentin is usually needed. This paper presents a non-invasive method for accessing internal tooth geometry by building 3-D tooth model from 2-D radiographic and endoscopic images to be used for an automatic prescription system of computer-aided treatment procedure planning, and for the root canal preparation by an intelligent micro drilling machine with on-line monitoring. It covers the techniques specific for dental application in the radiographic images acquirement, image enhancement, image segmentation and feature recognition, distance measurement and calibration, merging 2D image into 3D mathematical model representation and display. Included also are the methods to form references for irregular teeth geometry and to do accurately measurement with self-calibration.

  1. MRI study on spinal canal content in Western Maharashtrian population

    Directory of Open Access Journals (Sweden)

    Khanapurkar SV, Kulkarni DO, Bahetee BH, Vahane MI

    2014-07-01

    Full Text Available The morphology of the spinal canal content has been studied since the invention of myelography. However, most studies have measured the diameters of the spinal cord only, not the size of the subarachnoid space. The present study complements the current data on the morphology of the spinal contents, and in particular, the spinal subarachnoid space, by analyzing MRI images. Objective: To study morphology of the dural sac, spinal cord & subarachnoid space using MRI. To define the inner geometrical dimensions of spinal canal content that confine the maneuver of an endoscope inserted in cervical spine. 3. To have comprehensive knowledge of the anatomy of cervical spinal canal. Method: Based on MRI images of the spine from 60 normal patients of age between 25-60 years, the dimensions of spinal cord, dural sac & subarachnoid space were measured at mid-vertebral & intervertebral level from C1-C7 vertebrae. The parameters measured were transverse, sagittal diameter of spinal cord & dural sac. The subarachnoid space was measured as anterior, posterior, right, left distance between spinal cord and dura mater. Results: It was found that at each selected transverse level, the subarachnoid space tends to be symmetrical on the right and left sides of the cord, and measures 3.38 mm on an average. However, the anterior and posterior segment, measured on the mid-sagittal plane are generally asymmetric & varies greatly in size ranging 1mm to 6mm with mean 2.57 of anterior & 2.59 of posterior. These measurements match those found in previous studies. The coefficient of variance for the dimensions of the subarachnoid space is as high as 36.16%, while that for the dimensions of the spinal cord (transverse & sagittal are11.08%&13.28%respectively. Conclusion: The findings presented here, expand our knowledge of morphology of spinal canal and show that a thecaloscope must be smaller than 3.38 mm in diameter.

  2. [Membrane model of the cupula of the vestibular semicircular canals].

    Science.gov (United States)

    Kondrachuk, A V; Shipov, A A; Sirenko, S P

    1987-01-01

    A mathematical model of the time-course variations of the cupula of the semicircular canals of the vestibular apparatus is presented. The model is found to be in good agreement with experimental data which suggests that the cupular matter has viscosity-elasticity properties. Their role in the functioning of the vestibular apparatus is discussed in qualitative terms. The applicability of the membrane model to the description of the time-course variations of the cupula is considered.

  3. Panama canal watershed payment for environmental services project

    OpenAIRE

    IDIAP (Panamanian National Agricultural Research Institute); Montana State University; CIP; Food and Agriculture Organization

    2007-01-01

    Metadata only record The Panama canal produces around 15% of the Panama's gross domestic produce (GDP), and requires large quantities of water to function. The surrounding watershed has been subjected to large scale deforestation and an increase in the population. In order to reduce siltation and improve water storage capacity, this project will look at the feasibility of implementing a payment for environmental services project. It will examine land use alternatives and benefits, evaluate...

  4. Histopathology of subcutaneous tissue reaction to endodontic root canal sealers

    OpenAIRE

    2011-01-01

    The aim of the study was to evaluate tissue response of two root canal sealers: Endomethasone (cink oxide eugenol-based sealers) and Ketac Endo Aplicap (glass ionomer based sealers). The sealers were freshly mixed and injected into subcutaneous connective tissue of the dorsal surface of experimental animals (Wistar Furth rats). The inflammatory reaction caused by the sealers was evaluated 7, 30 and 60 days after implantation using descriptive hisopathologic...

  5. Semicircular Canals Circumvent Brownian Motion Overload of Mechanoreceptor Hair Cells

    Science.gov (United States)

    Muller, Mees; Heeck, Kier

    2016-01-01

    Vertebrate semicircular canals (SCC) first appeared in the vertebrates (i.e. ancestral fish) over 600 million years ago. In SCC the principal mechanoreceptors are hair cells, which as compared to cochlear hair cells are distinctly longer (70 vs. 7 μm), 10 times more compliant to bending (44 vs. 500 nN/m), and have a 100-fold higher tip displacement threshold (mechanoreceptors of the SCC. PMID:27448330

  6. Semicircular Canals Circumvent Brownian Motion Overload of Mechanoreceptor Hair Cells

    Science.gov (United States)

    Muller, Mees; Heeck, Kier

    2016-01-01

    Vertebrate semicircular canals (SCC) first appeared in the vertebrates (i.e. ancestral fish) over 600 million years ago. In SCC the principal mechanoreceptors are hair cells, which as compared to cochlear hair cells are distinctly longer (70 vs. 7 μm), 10 times more compliant to bending (44 vs. 500 nN/m), and have a 100-fold higher tip displacement threshold (level of the mechanoreceptors of the SCC. PMID:27448330

  7. The human semicircular canal model of galvanic vestibular stimulation

    OpenAIRE

    Day, B. L.; Ramsay, E.; Welgampola, M. S.; Fitzpatrick, R. C.

    2011-01-01

    A vector summation model of the action of galvanic stimuli on the semicircular canals has been shown to explain empirical balance and perceptual responses to binaural-bipolar stimuli. However, published data suggest binaural-monopolar stimuli evoke responses that are in the reverse direction of the model prediction. Here, we confirm this by measuring balance responses to binaural-monopolar stimulation as movements of the upper trunk. One explanation for the discrepancy is that the galvanic st...

  8. Comparative study of sealing ability of three root canal sealers

    Directory of Open Access Journals (Sweden)

    Khedmat S.

    2007-07-01

    Full Text Available Background and Aim: Complete obturation of the prepared root canal is an essential step in endodontic treatment. Combination of gutta-percha and a sealer is widely used in clinical practice for root canal obturation, thus microleakage studies on sealing properties of these materials constitute an important part of endodontic researches. The aim of this study was to evaluate the microleakage of three root canal sealers: Apexit, AH26 and Dorifill by electrochemical method.Materials and Methods: In this experimental study, 55 extracted human maxillary and mandibular cuspids were used. The coronal part of teeth were removed and the root canals were prepared using the step-back technique. The specimens were randomly divided into 3 groups of 17 samples each. Teeth in each group were filled with one of the sealers and gutta-percha by lateral condensation technique. 4 specimens served as positive and negative controls. An electrochemical method was used for evaluation of apical leakage with the electrical source potential of 10 V. Measurements of current flow through the test system were recorded every 72 hours. Data were analyzed by Kruskall Wallis and Mann Whitney tests. P<0.05 was considered as the level of significance.Results: All specimens of the three groups showed low initial leakage that increased during the test period. The mean leakage in Apexit group was higher than AH26 and Dorifill groups. The lowest mean leakage was related to Dorifill group. Although no statistically significant difference was observed between this sealer and AH26.Conclusion: The results of this study revealed that the best apical seal was obtained using Dorifill and AH26 sealers. The poorest result was observed in Apexit.

  9. Choice of root canal irrigants by Serbian dental practitioners

    Directory of Open Access Journals (Sweden)

    Tošić Goran

    2016-01-01

    Full Text Available Background/Aim. Root canal treatment is considered to be the one of the most important procedures in endodontic treatment. To irrigate the root canal it is most common to use sodium hypochlorite (NaOCl, chlorhexodine, ethylenediami-netetraacetic acid (EDTA, local anesthetic solution, while the most used in Serbia is hydrogen peroxide (H2O2. The aim of this survey was to reveal the preferred root canal irrigants used by general dental practitioners in Serbia and to determine the influence of the continuing education program, delivered over the 3-year observation period, on work habits of dental practitioners. This was the first comprehensive survey of this nature carried out in Serbia. Methods. The survey was conducted in two instances, a 4-month observation period each, from November 1, 2009 to March 1, 2010 and from November 1, 2012 to March 1, 2013. Internet Web Page Survey was posted on the official web site of the Serbian Association of Private Dentists. In the first survey, 569 completed questionnaires were subjected to analysis. In the next attempt (3 years later, the survey was launched again and 615 completed questionnaires were analyzed using the same criteria. The statistical analysis was carried out with simple descriptive statistics applying the χ2 test, at a significance level of p < 0.05. Results. The first survey included 569 dental practitioners, while 3 years later the number of them was 615. Analyzing the questionnaires revealed the number of 10 to 30 interventins on the root canal montly. The most commonly used irrigant solution was H2O2 in 2009, while in 2012 it was yet H2O2, but also NaOCl, chlorhexodine, and a little less EDTA. Conclusion. This study shows significant changes in the irrigation protocol applied in Serbian dental community. After 3 years of observation, NaOCl became widely accepted as the irrigant of choice, whereas H2O2 lost its popularity.

  10. Facies del subfondo del canal Beagle, Tierra del Fuego

    Directory of Open Access Journals (Sweden)

    Gustavo Bujalesky

    2004-03-01

    Full Text Available El canal Beagle conecta los océanos Pacífico y Atlántico en el extremo meridional de Sudamérica y se ubica en el ambiente subantártico. Conforma una cuenca de unos 300 m de profundidad máxima y está separada del océano Atlántico por un umbral de 30 m de profundidad. El canal es un valle tectónico que fue completamente cubierto por el hielo glacial durante la última glaciación. Posteriormente, el canal fue ocupado por un lago glacial desde los 12.000 a los 8.000 años A.P., cuando fue invadido por el mar que alcanzó un nivel máximo entre los 6.000 y 5.000 años A.P. Con el objetivo de analizar las facies sedimentarias superficiales y del subfondo del canal se realizó un relevamiento geofísico con sonar de barrido lateral y un perfilador de 3,5 kHz. Sobre un basamento constituido por rocas metamórficas del Mesozoico, se identificaron depósitos de till y secuencias granodecrecientes que representan distintos estadios del retroceso glaciar, evidenciando hacia la sección superior facies lacustres y por encima depósitos de la transgresión marina del Holoceno. Además, se han identificado paleocauces y secuencias fluviales cubiertas por sedimentos marinos transgresivos.

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

    International Nuclear Information System (INIS)

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

  12. Effect of postmilking teat antisepsis on teat canal infections in lactating dairy cows.

    Science.gov (United States)

    Nickerson, S C; Watts, J L; Boddie, R L; Ray, C H

    1990-02-01

    Effects of a .18% iodophor teat dip and a fatty acid plus lactic acid teat dip on teat canal infections were studied in two separate trials under experimental challenge procedures using Staphylococcus aureus and Streptococcus agalactiae. The iodophor teat dip was 90% effective in preventing new S. aureus teat canal infections and 95.6% effective in reducing progression of S. aureus teat canal infections to intramammary infections. The dip also reduced persistence of S. aureus teat canal colonizations from week to week by 94.4%. The fatty acid plus lactic acid dip had no effect on preventing S. aureus teat canal infections but reduced progression of S. aureus teat canal infections to intramammary infections by 43.8%. The fatty acid plus lactic acid dip also reduced the persistence of S. aureus teat canal infections by 39%. An insufficient number of Strep. agalactiae teat canal infections was detected in both trials for valid analyses. Neither dip had any effect on prevalence of naturally occurring, coagulase-negative staphylococcal teat canal infections or on teat canal infections by other organisms. PMID:2184176

  13. Endoscopic Transcanal Retrocochlear Approach to the Internal Auditory Canal with Cochlear Preservation: Pilot Cadaveric Study.

    Science.gov (United States)

    Kempfle, Judith; Kozin, Elliott D; Remenschneider, Aaron K; Eckhard, Andreas; Edge, Albert; Lee, Daniel J

    2016-05-01

    Contemporary operative approaches to the internal auditory canal (IAC) require the creation of large surgical portals for visualization with associated morbidity, including hearing loss, vestibular dysfunction, facial nerve injury, and skull base defects that increase the risk of cerebrospinal fluid leak. Transcanal approaches to the IAC have been possible only via a transcochlear technique. To preserve cochlear function, we describe a novel endoscopic transcanal infracochlear approach to the IAC in cadaveric temporal bones. Navigation fiducials were secured on fresh cadaveric heads, and real-time computed tomography imaging was used for surgical guidance. With a combination of curved instruments and rigid angled endoscopy, a transcanal hypotympanotomy and subcochlear tunnel were created with superior extension to access the IAC. Postprocedure imaging and temporal bone dissection confirmed access to the IAC without injury to the cochlea or neighboring neurovascular structures. PMID:26932951

  14. The clinical success of different root canal treatments in primary molars

    Directory of Open Access Journals (Sweden)

    Çiğdem Güler

    2013-01-01

    Full Text Available

    Objectives: To examine the success rate of root canal treatment in primary molars with the use two different root canal instrumentation ways, irrigation solutions and root canal sealers.

    Materials and Methods: Root canal treatment was applied to 120 second primary molars of 69 children between 5-8 years old. The teeth were divided in 8 groups randomly according to instrumentation ways [conventional stainless-steel hand files / Nickel-titanium (Ni-Ti rotary files], irrigation solutions [0.5% sodium hypochlorite (NaOCl and 0.9% saline solution combination / 0.4% chlorhehexidine (CHX] and root canal sealers [Zinc oxide eugenol cement (ZOE and Apexit Plus (AP]. All teeth were restored with stainless steel crowns. The teeth were followed 12 months both clinically and radiographically. All data was analyzed statistically by χ2 and Wilcoxon test.

    Results: Statistical significance were found according to “age” and “root canal sealers” factors on success rate of root canal treatment (p<0.05. No statistical significance were found according to gender, jaw, tooth type, root canal instrumentation ways and irrigation solutions  on success rate of root canal treatment (p>0.05. The clinically and radiographically success rate of ZOE and AP were 98.3% and 68.3%, respectively.

    Conclusions: Root canal treatment is a successful treatment in primary molars. Ni-Ti rotary files and CHX can be a good alternative for root canal treatment in primary molars. The most effective factor to obtain clinical success of root canal treatment is properties of using root canal sealer.

  15. Delineating ground water recharge from leaking irrigation canals using water chemistry and isotopes.

    Science.gov (United States)

    Harvey, F E; Sibray, S S

    2001-01-01

    Across the Great Plains irrigation canals are used to transport water to cropland. Many of these canals are unlined, and leakage from them has been the focus of an ongoing legal, economic, and philosophical debate as to whether this lost water should be considered waste or be viewed as a beneficial and reasonable use since it contributes to regional ground water recharge. While historically there has been much speculation about the impact of canal leakage on local ground water, actual data are scarce. This study was launched to investigate the impact of leakage from the Interstate Canal, in the western panhandle of Nebraska, on the hydrology and water quality of the local aquifer using water chemistry and environmental isotopes. Numerous monitoring wells were installed in and around a small wetland area adjacent to the canal, and ground water levels were monitored from June 1992 until January 1995. Using the water level data, the seepage loss from the canal was estimated. In addition, the canal, the monitoring wells, and several nearby stock and irrigation wells were sampled for inorganic and environmental isotope analysis to assess water quality changes, and to determine the extent of recharge resulting from canal leakage. The results of water level monitoring within study wells indicates a rise in local ground water levels occurs seasonally as a result of leakage during periods when the canal is filled. This rise redirects local ground water flow and provides water to nearby wetland ecosystems during the summer months. Chemical and isotopic results were used to delineate canal, surface, and ground water and indicate that leaking canal water recharges both the surface alluvial aquifer and upper portions of the underlying Brule Aquifer. The results of this study indicate that lining the Interstate Canal could lower ground water levels adjacent to the canal, and could adversely impact the local aquifer.

  16. Phage therapy against Enterococcus faecalis in dental root canals.

    Science.gov (United States)

    Khalifa, Leron; Shlezinger, Mor; Beyth, Shaul; Houri-Haddad, Yael; Coppenhagen-Glazer, Shunit; Beyth, Nurit; Hazan, Ronen

    2016-01-01

    Antibiotic resistance is an ever-growing problem faced by all major sectors of health care, including dentistry. Recurrent infections related to multidrug-resistant bacteria such as methicillin-resistant Staphylococcus aureus, carbapenem-resistant Enterobacteriaceae, and vancomycin-resistant enterococci (VRE) in hospitals are untreatable and question the effectiveness of notable drugs. Two major reasons for these recurrent infections are acquired antibiotic resistance genes and biofilm formation. None of the traditionally known effective techniques have been able to efficiently resolve these issues. Hence, development of a highly effective antibacterial practice has become inevitable. One example of a hard-to-eradicate pathogen in dentistry is Enterococcus faecalis, which is one of the most common threats observed in recurrent root canal treatment failures, of which the most problematic to treat are its biofilm-forming VRE strains. An effective response against such infections could be the use of bacteriophages (phages). Phage therapy was found to be highly effective against biofilm and multidrug-resistant bacteria and has other advantages like ease of isolation and possibilities for genetic manipulations. The potential of phage therapy in dentistry, in particular against E. faecalis biofilms in root canals, is almost unexplored. Here we review the efforts to develop phage therapy against biofilms. We also focus on the phages isolated against E. faecalis and discuss the possibility of using phages against E. faecalis biofilm in root canals. PMID:27640530

  17. Dynamic displacement of normal and detached semicircular canal cupula.

    Science.gov (United States)

    Rabbitt, Richard D; Breneman, Kathryn D; King, Curtis; Yamauchi, Angela M; Boyle, Richard; Highstein, Stephen M

    2009-12-01

    The dynamic displacement of the semicircular canal cupula and modulation of afferent nerve discharge were measured simultaneously in response to physiological stimuli in vivo. The adaptation time constant(s) of normal cupulae in response to step stimuli averaged 36 s, corresponding to a mechanical lower corner frequency for sinusoidal stimuli of 0.0044 Hz. For stimuli equivalent to 40-200 deg/s of angular head velocity, the displacement gain of the central region of the cupula averaged 53 nm per deg/s. Afferents adapted more rapidly than the cupula, demonstrating the presence of a relaxation process that contributes significantly to the neural representation of angular head motions by the discharge patterns of canal afferent neurons. We also investigated changes in time constants of the cupula and afferents following detachment of the cupula at its apex-mechanical detachment that occurs in response to excessive transcupular endolymph pressure. Detached cupulae exhibited sharply reduced adaptation time constants (300 ms-3 s, n = 3) and can be explained by endolymph flowing rapidly over the apex of the cupula. Partially detached cupulae reattached and normal afferent discharge patterns were recovered 5-7 h following detachment. This regeneration process may have relevance to the recovery of semicircular canal function following head trauma.

  18. Ocean ambient sound south of Bermuda and Panama Canal traffic.

    Science.gov (United States)

    Širović, Ana; Hildebrand, John A; McDonald, Mark A

    2016-05-01

    Comparisons of current and historic ocean ambient noise levels are rare, especially in the North Atlantic. Recent (2013-2014) monthly patterns in ocean ambient sound south of Bermuda were compared to those recorded at the same location in 1966. Additionally, trends in ocean traffic, in particular, Panama Canal traffic, over this time were also investigated. One year of ocean ambient noise measurements were collected in 1966 using cabled, omnidirectional hydrophones at the U.S. Navy Tudor Hill Laboratory in Bermuda, and repeat measurements were collected at the same location from June 2013-May 2014 using a High-frequency Acoustic Recording Package. Average monthly pressure spectrum levels at 44 Hz increased 2.8 ± 0.8 dB from 1966 to 2013, indicating an average increase of 0.6 dB/decade. This low level of increase may be due to topographic shielding at this site, limiting it to only southern exposure, and the limit in the number of ship transits through the Panama Canal, which did not change substantially during this time. The impending expansion of the Canal, which will enable the transit of larger ships at twice the current rate, is likely to lead to a substantial increase in ocean ambient sound at this location in the near future.

  19. Intraoperative ultrasonography of the vertebral canal in dogs

    Directory of Open Access Journals (Sweden)

    M.A. Bonelli

    2015-06-01

    Full Text Available Intraoperative ultrasound (IOS can provide details on various conditions of the spinal cord and vertebral canal. The aim of the present study was to evaluate the feasibility of using IOS in dogs undergoing spinal surgery and to describe the main findings. The vertebral canal of 21 dogs was examined with intraoperative ultrasonography: 13 underwent spinal surgery for removal of herniated intervertebral disc material, three for stabilization of vertebral fracture/luxation, two for removal of vertebral neoplasia, and three for cauda equina decompression. Particular attention was given to signs of cord compression. Intraoperative ultrasonography was feasible and useful in dogs undergoing surgery for spinal cord or cauda equina decompression and fracture stabilization. It was not paramount for locating the compression when this had been done via computed tomography (CT, but it showed alterations in spinal cord parenchyma not observed on CT and also confirmed adequate decompression of the spinal cord. The main advantages of intraoperative ultrasonography were estimation of vascularization and extent of spinal cord lesion. Most importantly, it allowed real time evaluation of the spinal cord and vertebral canal, which permits the modification of the surgical procedure.

  20. An electrokinetic model of transduction in the semicircular canal.

    Science.gov (United States)

    O'Leary, D P

    1970-09-01

    Transduction in the semicircular canal was studied by focusing an infrared beam on either side of exposed ampullae from the posterior canals of Rana pipiens. The direction of fluid movement resulting from a stimulus was inferred by observing the polarity of the change in afferent impulse mean rate relative to the spontaneous value. On the basis of the accepted functional polarization of this receptor, the results indicate that fluid moved toward the warmer side of the ampulla. Convection and thermal reception were shown to be unlikely explanations for these results. Morover, cupular displacements toward the warmer side would not be expected. Because thermo-osmosis can cause fluid to move toward the warmer side in a gelatin membrane, the results can be interpreted as evidence that thermo-osmosis occurred in the gelatinous cupula and influenced the transduction mechanism. Thermo-osmosis of liquids appears to be due to an electric field that is set up in a charged membrane; hence, the hair cells might have detected an electric field that occurred in the cupula during thermo-osmosis. Electroreception might be an important link in the transduction of physiological stimuli also. Rotational stimuli could result in weak electric fields in the cupula by the mechanoelectric effect. Cupular displacements could be important for large stimuli, but extrapolations to threshold stimuli suggest displacements of angstrom amplitudes. Therefore, electroreception by the hair cells could be an explanation of the great sensitivity that has been observed in the semicircular canal and other labyrinthine receptors. PMID:5496906

  1. Ocean ambient sound south of Bermuda and Panama Canal traffic.

    Science.gov (United States)

    Širović, Ana; Hildebrand, John A; McDonald, Mark A

    2016-05-01

    Comparisons of current and historic ocean ambient noise levels are rare, especially in the North Atlantic. Recent (2013-2014) monthly patterns in ocean ambient sound south of Bermuda were compared to those recorded at the same location in 1966. Additionally, trends in ocean traffic, in particular, Panama Canal traffic, over this time were also investigated. One year of ocean ambient noise measurements were collected in 1966 using cabled, omnidirectional hydrophones at the U.S. Navy Tudor Hill Laboratory in Bermuda, and repeat measurements were collected at the same location from June 2013-May 2014 using a High-frequency Acoustic Recording Package. Average monthly pressure spectrum levels at 44 Hz increased 2.8 ± 0.8 dB from 1966 to 2013, indicating an average increase of 0.6 dB/decade. This low level of increase may be due to topographic shielding at this site, limiting it to only southern exposure, and the limit in the number of ship transits through the Panama Canal, which did not change substantially during this time. The impending expansion of the Canal, which will enable the transit of larger ships at twice the current rate, is likely to lead to a substantial increase in ocean ambient sound at this location in the near future. PMID:27250138

  2. Phage therapy against Enterococcus faecalis in dental root canals

    Science.gov (United States)

    Khalifa, Leron; Shlezinger, Mor; Beyth, Shaul; Houri-Haddad, Yael; Coppenhagen-Glazer, Shunit; Beyth, Nurit; Hazan, Ronen

    2016-01-01

    Antibiotic resistance is an ever-growing problem faced by all major sectors of health care, including dentistry. Recurrent infections related to multidrug-resistant bacteria such as methicillin-resistant Staphylococcus aureus, carbapenem-resistant Enterobacteriaceae, and vancomycin-resistant enterococci (VRE) in hospitals are untreatable and question the effectiveness of notable drugs. Two major reasons for these recurrent infections are acquired antibiotic resistance genes and biofilm formation. None of the traditionally known effective techniques have been able to efficiently resolve these issues. Hence, development of a highly effective antibacterial practice has become inevitable. One example of a hard-to-eradicate pathogen in dentistry is Enterococcus faecalis, which is one of the most common threats observed in recurrent root canal treatment failures, of which the most problematic to treat are its biofilm-forming VRE strains. An effective response against such infections could be the use of bacteriophages (phages). Phage therapy was found to be highly effective against biofilm and multidrug-resistant bacteria and has other advantages like ease of isolation and possibilities for genetic manipulations. The potential of phage therapy in dentistry, in particular against E. faecalis biofilms in root canals, is almost unexplored. Here we review the efforts to develop phage therapy against biofilms. We also focus on the phages isolated against E. faecalis and discuss the possibility of using phages against E. faecalis biofilm in root canals. PMID:27640530

  3. Phage therapy against Enterococcus faecalis in dental root canals

    Directory of Open Access Journals (Sweden)

    Leron Khalifa

    2016-09-01

    Full Text Available Antibiotic resistance is an ever-growing problem faced by all major sectors of health care, including dentistry. Recurrent infections related to multidrug-resistant bacteria such as methicillin-resistant Staphylococcus aureus, carbapenem-resistant Enterobacteriaceae, and vancomycin-resistant enterococci (VRE in hospitals are untreatable and question the effectiveness of notable drugs. Two major reasons for these recurrent infections are acquired antibiotic resistance genes and biofilm formation. None of the traditionally known effective techniques have been able to efficiently resolve these issues. Hence, development of a highly effective antibacterial practice has become inevitable. One example of a hard-to-eradicate pathogen in dentistry is Enterococcus faecalis, which is one of the most common threats observed in recurrent root canal treatment failures, of which the most problematic to treat are its biofilm-forming VRE strains. An effective response against such infections could be the use of bacteriophages (phages. Phage therapy was found to be highly effective against biofilm and multidrug-resistant bacteria and has other advantages like ease of isolation and possibilities for genetic manipulations. The potential of phage therapy in dentistry, in particular against E. faecalis biofilms in root canals, is almost unexplored. Here we review the efforts to develop phage therapy against biofilms. We also focus on the phages isolated against E. faecalis and discuss the possibility of using phages against E. faecalis biofilm in root canals.

  4. Sexually antagonistic epigenetic marks that canalize sexually dimorphic development.

    Science.gov (United States)

    Rice, William R; Friberg, Urban; Gavrilets, Sergey

    2016-04-01

    The sexes share the same autosomal genomes, yet sexual dimorphism is common due to sex-specific gene expression. When present, XX and XY karyotypes trigger alternate regulatory cascades that determine sex-specific gene expression profiles. In mammals, secretion of testosterone (T) by the testes during foetal development is the master switch influencing the gene expression pathways (male vs. female) that will be followed, but many genes have sex-specific expression prior to T secretion. Environmental factors, like endocrine disruptors and mimics, can interfere with sexual development. However, sex-specific ontogeny can be canalized by the production of epigenetic marks (epimarks) generated during early ontogeny that increase sensitivity of XY embryos to T and decrease sensitivity of XX embryos. Here, we integrate and synthesize the evidence indicating that canalizing epimarks are produced during early ontogeny. We will also describe the evidence that such epimarks sometimes carry over across generations and produce mosaicism in which some traits are discordant with the gonad. Such carryover epimarks are sexually antagonistic because they benefit the individual in which they were formed (via canalization) but harm opposite-sex offspring when they fail to erase across generations and produce gonad-trait discordances. SA-epimarks have the potential to: i) magnify phenotypic variation for many sexually selected traits, ii) generate overlap along many dimensions of the masculinity/femininity spectrum, and iii) influence medically important gonad-trait discordances like cryptorchidism, hypospadias and idiopathic hirsutism. PMID:26600375

  5. Cadmium and chromium concentrations in six forage species irrigated with canal, sewage or mixed canal and sewage water

    International Nuclear Information System (INIS)

    Cadmium (Cd) and chromium (Cr) concentrations were investigated in six different forage species, i.e., Trifolium alexandrium, Cichorium intybus, Avena sativa, Medicago polymorpha, Brassica campestris and Medicago sativa, irrigated with canal, sewage or mixed canal and sewage water. The Cd levels of the forages irrigated with different water treatments in this study were greater than the tolerance level for grazing livestock reported in the literature. Thus, the Cd levels in the six plant species found in the current study showed high potential threat for livestock consuming these forages. Similarly, high levels of Cr in the six forages were observed with sewage water treatment only. However, in the present investigation, Cr concentration of forages was below the toxic level. Therefore, there was no threat of Cr toxicity for animals being reared on these forages. (author)

  6. Forced extrusion for removal of impacted third molars close to the mandibular canal Extrusión forzada para extraer los terceros molares impactados cerca del canal mandibular

    Directory of Open Access Journals (Sweden)

    Dennis Flanagan DDS

    2012-03-01

    Full Text Available Impacted mandibular third molars can be located in close proximity to the mandibular canal. This creates a risk for the nerve or artery injury. These are contained in the canal. However, the impacted third molar can be moved coronally by orthodontic means, after removal of overlying bone, and safely extracted. The orthodontic intervention slowly moves the tooth apex away from the mandibular canal and reduces the potential for a neural injury. This method may be useful for older patients with root apices that approximate or are actually located in the mandibular canal. This technique needs further study. There is a theoretical potential for neural or arterial injury from physical contact of the tooth apex as it moves by or through the mandibular canal.Los terceros molares inferiores impactados pueden localizarse muy cerca del canal mandibular. Esto constituye un riesgo de lesión del nervio o la arteria, que se localizan dentro del canal. No obstante, el tercer molar impactado puede desplazarse en dirección coronal con ortodoncia, tras ostectomía del hueso suprayacente, y extraerse sin riesgos. La intervención ortodóncica desplaza lentamente el ápice del diente fuera del canal mandibular y reduce la posibilidad de lesión neural. Este método puede ser útil para pacientes de edad avanzada con ápices dentales que se aproximan o en realidad se localizan en el canal mandibular. La técnica necesita un estudio adicional. Hay la posibilidad teórica de lesión neural o arterial a partir del contacto físico del ápice del diente a medida que se desplaza a través del canal mandibular.

  7. Anatomy of Mandibular Vital Structures. Part II: Mandibular Incisive Canal, Mental Foramen and Associated Neurovascular Bundles in Relation with Dental Implantology

    Directory of Open Access Journals (Sweden)

    Gintautas Sabalys

    2010-01-01

    Full Text Available Objectives: The purpose of the present study was to review the literature of how to identify the mental foramen, mandibular incisive canal and associated neurovascular bundles during implant surgery and how to detect and avoid the damage of these vital structures during implant therapy.Material and Methods: Literature was selected through a search of PubMed, Embase and Cochrane electronic databases. The keywords used for search were mandibular incisive canal, mental foramen, mental nerve, anterior mental loop. The search was restricted to English language articles, published from 1979 to November 2009. Additionally, a manual search in the major anatomy, dental implant, and periodontal journals and books was performed.Results: In total, 47 literature sources were obtained and reviewed. The morphology and variations of the mandibular incisive canal, mental foramen and associated neurovascular bundles were presented as two entities. It suggested that clinicians should carefully assess these vital structures to avoid nerve/artery damage.Conclusions: The mandibular incisive canal, mental foramen and associated neurovascular bundles exist in different locations and possess many variations. Individual, gender, age, race, assessing technique used and degree of edentulous alveolar bone atrophy largely influence these variations. It suggests that the clinicians should carefully identify these anatomical landmarks, by analyzing all influencing factors, prior to their implant surgical operation.

  8. La crisis del Canal de Suez en 1956: el fin de una época en el Medio Oriente y el comienzo de otra

    Directory of Open Access Journals (Sweden)

    Efraim Davidi

    2009-12-01

    Full Text Available La crisis del Canal de Suez (o Campaña de Suez, Guerra de Suez u Operación Kadesh fue una guerra que estalla en 1956 en territorio egipcio. El conflicto que opone a Egipto a una alianza formada por Gran Bretaña, Francia e Israel se produce a consecuencia de la nacionalización del Canal de Suez por el dirigente egipcio Gamal Abdel Nasser. Esta alianza entre dos estados europeos e Israel respondió a intereses comunes: económicos, comerciales y políticos. Durante el curso del mes que siguió a la nacionalización del Canal, un acuerdo secreto fue firmado en Sèvres, en las afueras de Paris, en el cual se selló la cooperación militar de Gran Bretaña, Francia e Israel contra Egipto.______________________ABSTRACT:The Suez Crisis (the Suez War, the Kadesh Operation, or the Suez Campaign is a war on Egyptian territory what started with a tripartite aggression by Great Britain, France and Israel against Egypt in 1956, after the nationalization of the Suez Canal by Egyptian leader Gamal Abdel Nasser. The war plot against Egypt was hatched towards the end of October 1956 in a secret meeting in Sèvres, near Paris. The discussions culminated in the signature of the Protocol of Sèvres.

  9. EPA's monitoring program at Love Canal 1980.

    Science.gov (United States)

    Hauser, T R; Bromberg, S M

    1982-09-01

    As stated at the beginning of this paper conclusions reached thus far cannot be discussed in this paper. However, a great deal of information is available for examination.EPA displayed its ability to coordinate widely separated laboratories, both Federal and private, into a smooth working team in a very short period of time. A very comprehensive study plan was also developed and implemented quickly. EPA was fortunate to have already had GCA under contract when the emergency arose. In no small part the success of the field effort was due to the managerial and technical abilities of the GCA team.Within a period of 6 weeks a plan was developed, a prime contractor retained, subcontractors hired, and field activities begun. Within a period of 3 months in excess of 8600 field samples were collected and over 12,000 field and QC samples were analyzed. During this same period 2 major data systems were developed, debugged, and placed into operation.In short this EPA project was probably the most comprehensive multimedia field project ever attempted by EPA and certainly the data is being subjected to the most strenuous quality control measures ever imposed by this Agency. The entire program is presently under peer review and the results are being prepared for publication by EPA Headquarters.

  10. Application of one-time root canal therapy using different root canal filling materials%不同填充材料在一次性根管治疗中的应用分析

    Institute of Scientific and Technical Information of China (English)

    罗毅; 章凯

    2012-01-01

      Objective To compare the clinical effect of three different root canal filling materials in oral medicine in the treatment of one-time root canal therapy. Methods Collecting 213 patients,330 teeth in writer's outpatient from January 2010 to January 2011, randomly divided into three groups, treated with different root canal filling materials: Vitapex sealer (group A), Cortisomol sealer(group B) and zinc oxide clove oil iodoform paste (group C), to compare after one week treatment in patients with pain and the cure rate after one year later. Results The root canal therapy after one week, A group of pain was 13.6%, and 16.4% for group B, C group is 28.2%,group C was significantly higher than A and B group (P 0.05). Conclusion In the same operating conditions, Vitapex sealer and Cortisomol sealer than iodoform paste zinc oxide clove oil sealer have better effects,they are ideal root canal filling materials.%  目的对比口腔内科3种不同的根管填充材料在一次性根管治疗中的临床效果.方法2010年1月~2011年1月于笔者所在门诊收治的各类牙髓炎、根尖周炎需进行根管治疗的患者共213例,330颗牙.随机分为3组,分别采用Vitapex 糊剂(A 组)、Cortisomol 糊剂(B 组)以及碘仿氧化锌丁香油糊剂(C 组)进行根管填充,比较3组根管填充治疗1周后患者疼痛情况及术后1年的治愈率.结果根管治疗1周后,A 组疼痛发生率为13.6%,B 组为16.4%,C 组为28.2%, C 组疼痛发生率明显高于 A、B 组(P 0.05).结论在同等的操作条件下 Vitapex 糊剂、Cortisomol 糊剂比碘仿氧化锌丁香油糊剂有更好的疗效,是较为理想的根充材料.

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

    Directory of Open Access Journals (Sweden)

    Fabiana Soares Grecca

    2007-04-01

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

  12. The spread of injectate during saphenous nerve block at the adductor canal

    DEFF Research Database (Denmark)

    Andersen, H L; Andersen, S L; Tranum-Jensen, J

    2015-01-01

    BACKGROUND: The spread of injectate during a saphenous nerve block at the adductor canal has not been clearly described. METHODS: We examined the spread of 15 ml dyed injectate during ultrasound-guided saphenous nerve blocks at the adductor canal in 15 unembalmed cadavers' lower limbs followed...... by comparative dissections of the same limbs. RESULTS: The spread of the injectates was determined by the fascial limits and the muscles surrounding the adductor canal. The anteromedial limit of the adductor canal (the roof) was found to be a continuous fascia, with a thin proximal part and a thicker distal part...... and reached 1-2 cm into the popliteal fossa. Injections superficial to the adductor canal spread over the femoral artery within the subsartorial fat compartment resembling the injections within the canal but with ultrasonographic distinct features. These injections spread only half the length of the adductor...

  13. The role of perilymph in the response of the semicircular canals to angular acceleration.

    Science.gov (United States)

    Anliker, M.; Van Buskirk, W.

    1971-01-01

    A new model for the response of the semicircular canals to angular motion is postulated. This model is based on evidence that the bony canal is not compartmentalized and assumes that the ampulla wall is highly flexible. It is shown that the perilymph induces a cupula displacement far greater than that produced by the endolymph alone. The predicted dynamic behavior of the canals on the basis of this model is found to be consistent with experimental observations.

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

    DEFF Research Database (Denmark)

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

    2002-01-01

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

  15. Partial absence of the posterior semicircular canal in Alagille syndrome: CT findings

    Energy Technology Data Exchange (ETDEWEB)

    Koch, Bernadette; Egelhoff, John; Benton, Corning [Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati (United States); Goold, Amy [Tripler Army Medical Center, Family Practice, Honolulu, HI (United States)

    2006-09-15

    We report a case of bilateral partial absence of the posterior semicircular canals (with normal lateral semicircular canals) imaged with CT in a patient with Alagille syndrome. Similar histologic findings have been reported in the pathology literature. This association has been previously reported only for Waardenburg syndrome in the imaging literature. We review the imaging findings and embryology of the semicircular canals, and suggest that this abnormality is specific to patients with Alagille or Waardenburg syndrome. (orig.)

  16. Introducing Radio-Opaque Radio-Lucent Graduated Root Canal Length Indicating Cones (GRCLIC) in Endodontics

    OpenAIRE

    Mohammad R.S. Bonjar

    2007-01-01

    Radio Opaque-Radiolucent Graduated Root-Canal Length Indicating Cone (GRCLIC) is a new innovative device being introduced for the first time in endodontics literature. GRCLIC can present more accurate measurement of the root canal length in conventional radiographs in endodontic and root canal treatment. Like many other dental and medical specialties, endodontics has evolved and changed over the years. The changes that have occurred in the past 10 years, however, have been of great magnitude ...

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

    OpenAIRE

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

    2015-01-01

    Introduction: 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). Methods and Materials: 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 incub...

  18. Chlorhexidine as a root canal irrigant: Antimicrobial and scanning electron microscopic evaluation

    OpenAIRE

    Živković Slavoljub; Pavlović Violeta

    2010-01-01

    Introduction. Selection of irrigant is very important for longterm success of root canal therapy. Objective. This study was undertaken to evaluate the antimicrobial effects of 2% chlorhexidine digluconate solution (CHX) against five selected microorganisms and to evaluate its efficacy in root canal cleaning. Methods. In this study, by agar diffusion test, were evaluated antimicrobial effects of three root canal irrigants: 5.25% NaOCl, 2.5% NaOCl and 2% CHX. The microorganisms tested in ...

  19. The Effect of Three Irrigants on the Coronal Leakage of the Root Canals System Irrigants

    OpenAIRE

    Zare Jahromi, Maryam; Barekatain, Mehrdad; Ebrahimi, Maziar; Askari, Bahare

    2010-01-01

    INTRODUCTION The production of smear layer during canal instrumentation is thought to increase coronal microleakage even after canal obturation. Previous studies have shown that the type of irrigant does not necessarily affect the seal of the obturation. Our study aimed to evaluate the effect of three irrigation solutions (MTAD, citric acid and EDTA/NaOCl) on the coronal microleakage of root canals. MATERIALS AND METHODS Fifty five intact single rooted teeth were instrumented and randomly div...

  20. In vitro comparison of antimicrobial effectiveness of QMix and other final irrigants in human root canals

    OpenAIRE

    Ying Liu; Lili Guo; Yuqin Li; Xiangjun Guo; Bin Wang; Ligeng Wu

    2015-01-01

    Final root canal irrigation stands as an effective strategy for eliminating the dentin infection. This study aimed to investigate and compare the antibacterial efficacy of QMix and other four final irrigation regimens in reducing Enterococcus faecalis within human root canals. Single-canal human teeth contaminated with E. faecalis for 4 weeks were prepared chemomechanically with sodium hypochlorite (NaOCl). Then, the teeth were randomly assigned into six groups according to the final irrigati...

  1. Shaping ability of Lightspeed rotary nickel-titanium instruments in simulated root canals. Part 2.

    Science.gov (United States)

    Thompson, S A; Dummer, P M

    1997-12-01

    The aim of this laboratory based study was to determine the shaping ability of Lightspeed nickel-titanium rotary instruments in simulated root canals. A total of 40 canals with four different shapes in terms of angle and position of curve were prepared with Lightspeed instruments using the stepback technique recommended by the manufacturer. This report describes the efficacy of the instruments in terms of prevalence of canal aberrations, the amount and direction of canal transportation, and overall postoperative shape. Preoperative and postoperative images of the canals were taken using a video camera attached to a computer with image analysis software. The preoperative and postoperative views were superimposed to highlight the amount and position of material removed during preparation. Only one (2.5%) zip and one elbow were created, with no ledges, perforations, danger zones, or blockages being produced. At specific points along the canal length there were highly significant differences (p canal shapes in total canal width and in the amount of resin removed from the inner and outer aspects of the curve. The direction of canal transportation at the end point of preparation was most frequently toward the outer aspect of the curve; although in half of the canals, transportation was either directed toward the inner aspect or not observed. At the apex of the curve, the beginning of the curve, and halfway to the orifice, transportation was reversed with the majority of canals being transported toward the inner aspect of the curve. Mean absolute transportation was small and was below 0.06 mm at every position except the orifice. Overall, Lightspeed rotary instruments prepared canals well and would appear to be a valuable addition to the endodontic armamentarium. PMID:9487850

  2. Dental implants in bilateral bifid canal and compromised interocclusal space using cone beam computerized tomography

    Science.gov (United States)

    Ahmed, Nizar; Arunachalam, Lalitha Tanjore; Jacob, Caroline Annette; Kumar, Suresh Anand

    2016-01-01

    Knowledge of various anatomic landmarks is pivotal for important success. Bifid canals pose a challenge and can lead to difficulties while performing implant surgery in the mandible. Bifid canals can be diagnosed with panoramic radiography and more accurately with cone beam computerized tomography (CBCT). This case report details the placement of the implant in a patient with bilateral bifid canal and compromised interocclusal space, which was successfully treated using CBCT. PMID:27433073

  3. Comparison of Irrigation Penetration into the Apical Part of Canals in Hand and Rotary Instrumentations

    Directory of Open Access Journals (Sweden)

    M. Khabiri

    2007-01-01

    Full Text Available Introduction: The penetration of irrigating solution to the apical one third of canals and removal of debris are dependent on the final size of the instruments and instrumentation techniques used in the canals. The purpose of this study was to evaluate the effect of final instrument size, on irrigation penetration into the apical part of canals in hand K-file instrumentation versus rotary system of Hero 642.Methods and Materials: The mesiobuccal canals of 48 first mandibular molar teeth were selected for this study. The teeth were divided into 2 groups of 24 in each and the mesiobuccal canals were instrumented by hand K-file or rotary system of Hero 642 at 2 stages. After each stage, a contrast medium was injected into the canals and radiographs were taken by RVG system. The irrigation penetration was measured in radiographs by Diamax software. The data were analyzed using t – student test.Results: This study showed that instrumentation up to # 25 file is not enough for irrigation penetration into the apical area. Also by more flaring the canals, more irrigating solution penetrates into the apical part of canals (P 0 0.001, but the difference between hand and rotary systems was not statistically significant (P > 0.05.Discussion: According to this study, instrumentation up to # 30 file results in better irrigation penetration into the apical area. The flaring of the canals is essential for better cleaning and irrigation of apical area.

  4. Radiographic Evaluation of Root and Canal Morphologies of Third Molar Teeth in Iranian Population

    Directory of Open Access Journals (Sweden)

    Faramarzi

    2013-06-01

    Full Text Available Background Root and canal morphology of teeth has a significant role in endodontic treatment success. Third molars have strategic roles after losing first and second molars. Objectives This study investigated the morphology of permanent third molar using radiography in Dentistry University of Hamadan during 2011. Materials and Methods In this experimental study, 352 extracted molars (179 maxillary and 173 mandibular molars were collected. After preparing access cavity and file placement in canals, to investigate the number of roots, canals and canal type periapical radiographies were taken from two directions (mesiodistal and buccolingual. The results were analyzed using SPSS version 16.0 software and descriptive statistics. Results According to the study on 173 mandibular third molars, 92.4%, 4.6%, and 2.89% had two, one, and three roots, respectively. Majority of them had two or three canals and most of mesial root canals were type 2; but in 179 maxillary third molars, findings showed that 67.6%, 15%, 11.7%, and 5.6% of teeth had three, one, two, and four roots, respectively, majority of which had three canals (68.7%. Canals of 100% of distobuccal and palatal roots and 91% of mesiobuccal roots were type 1. Conclusions However, root and canal anatomies of third molar teeth are unknown, but studies focusing on third molar teeth have shown their possibility of treatment.

  5. Management of C-shaped root canal configuration with three different obturation systems

    Directory of Open Access Journals (Sweden)

    Deenadayalan Elumalai

    2015-01-01

    Full Text Available Unusual root canal anatomy always poses a diagnostic and treatment challenge. Identification of such variation is important for the success of the root canal treatment outcome. The C-shaped root canal configuration is one of the aberrant morphology of molar teeth, commonly the mandibular second molar. In this configuration, the canals are connected by slit or web. The presence of fin, slit and web makes through debridement obstacle for the clinician. This case reports present successful management of C-shaped mandibular molars with three different obturation systems.

  6. Root canal treatment of bilateral three-rooted maxillary first premolars

    Directory of Open Access Journals (Sweden)

    Bhavana Gandhi

    2012-01-01

    Full Text Available In endodontics, several anatomic variations occur in teeth, both externally and in the internal root morphology, which play a very significant role in the diagnosis and treatment outcome. A thorough knowledge of the root canal anatomy, careful interpretation of the angled radiographs, proper endodontic access cavity preparation, and exploration of the root canal are the prerequisites for endodontic success. In a maxillary first premolar, it is rare to find extra roots and canals, and the aim of the present article is to report a case about the successful diagnosis and clinical management of bilateral three-rooted maxillary first premolars, with three independent root canals.

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

    Directory of Open Access Journals (Sweden)

    Vita Nirmala

    2006-03-01

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

  8. Groundwater quality and soil salinization in a canal command area and management options

    International Nuclear Information System (INIS)

    This study was undertaken to examine the groundwater quality and soil salinization in canal irrigated areas. Data were collected along six secondary canals (2 each at head, middle and tail end) of a main canal and nine tertiary canals (3 each at head, middle and tail) on each of the secondary canal. The farmers were also interviewed to investigate the impact of location along the irrigation channels on their crop yield and income. The results showed that groundwater quality has deteriorated from head to tail reaches of the irrigation channels i.e. the main canal, the secondary and the tertiary canals. Similarly, the soil salinization has increased with increase in distance from the head of the irrigation system along all the irrigation channels. Location of the water users along the canal irrigation system has significant impact on their crop yield as well as income and these parameters decrease with increase in distance from the head of the irrigation channels. The net income of the tail end farmers is only 43-59% of the head end farmers. The reduced canal water supply at lower reaches of the irrigation system forced the down reach water users to pump more groundwater of inferior quality resulting in many times increase in their irrigation cost. The deteriorating groundwater quality further added misery to the downstream farmers by degrading productivity of their lands due to increased soil salinity. (author)

  9. A comparative study of accuracy of linear measurements using cone beam and multi-slice computed tomographies for evaluation of mandibular canal location in dry mandibles

    OpenAIRE

    Naser, Asieh Zamani; Mehr, Bahar Behdad

    2013-01-01

    Background: Cross- sectional tomograms have been used for optimal pre-operative planning of dental implant placement. The aim of the present study was to assess the accuracy of Cone Beam Computed Tomography (CBCT) measurements of specific distances around the mandibular canal by comparing them to those obtained from Multi-Slice Computed Tomography (MSCT) images. Materials and Methods: Ten hemi-mandible specimens were examined using CBCT and MSCT. Before imaging, wires were placed at 7 locatio...

  10. A comparative study of accuracy of linear measurements using cone beam and multi-slice computed tomographies for evaluation of mandibular canal location in dry mandibles

    OpenAIRE

    Asieh Zamani Naser; Bahar Behdad Mehr

    2013-01-01

    Background: Cross- sectional tomograms have been used for optimal pre-operative planning of dental implant placement. The aim of the present study was to assess the accuracy of Cone Beam Computed Tomography (CBCT) measurements of specific distances around the mandibular canal by comparing them to those obtained from Multi-Slice Computed Tomography (MSCT) images. Materials and Methods: Ten hemi-mandible specimens were examined using CBCT and MSCT. Before imaging, wires were placed at 7 loc...

  11. Dentascan CT of mandibular incisive canal. Radiological anatomy and therapeutic implications; Tomografia computerizzata con Dentascan del canale incisivo mandibolare. Anatomia radiologica e implicazioni terapeutiche

    Energy Technology Data Exchange (ETDEWEB)

    Calgaro, A.; Bison, L.; Bellis, G.B.; Pozzi Mucelli, R. [Trieste Univ., Trieste (Italy). Ist. di radiologia

    1999-11-01

    The main purpose of this paper is to stress the importance of CT depiction of the mandibular incisive canal. This anatomical structure contains a major neurovascular bundle and is thus very important in the planning of mandibular implants in the canine-incisive area. The importance of careful assessment of the mandibular canal course before implantology is now widely recognized. The same holds true for the canine-incisive region in the jaw, to detect the incisive canal if present and prevent any complications from its accidental damage. CT with a dedicated software showed the incisive canal in a large number of patients, which calls for precise reporting of its presence, course, and relationships with teeth. [Italian] Scopo di questo lavoro e' sottolineare l'importanza di rilevare e segnalare la visibilita' con Tomografia Computerizzata del canale incisivo mandibolare, struttura anatomica al cui interno decorre un fascio vasculo nervoso e percio' di rilevante importanza in previsione di intervento implantologico nella regione mesiale della mandibola. In previsione di seduta implantologica appare fondamentale l'attenta valutazione non solo del decorso del canale mandibolare ma anche della regione canino-incisiva della mandibola per la possibile esistenza del canale incisivo al fine di evitare eventuali complicanze derivanti dal suo accidentale danneggiamento. Il riscontro di tale struttura con TC con programma dedicato e apparso tutt'altro che trascurabile e percio' risulta di primaria importanza segnalarne presenza, decorso ed eventuali rapporti con gli elementi dentari.

  12. Retreatment of a Maxillary Lateral Incisor With Two Separate Root Canals Confirmed With Cone Beam Computed Tomography

    Science.gov (United States)

    Aydemir, Seda; Helvacioglu-Yigit, Dilek; Sinanoglu, Alper; Ozel, Emre

    2015-01-01

    The purpose of this report is to present a rare case of a maxillary lateral incisor exhibiting two separate root canals confirmed by cone-beam computed tomography (CBCT). A 65-year-old female patient with an esthetic complaint regarding her maxillary left lateral incisor was referred to our clinic. During a radiographical examination, an endodontically treated root canal and an extra root canal with an apical lesion were observed. The retreatment was performed. CBCT findings confirmed the root canal mophology of the maxillary left lateral with two distinct canals. We conclude that the CBCT imaging is an adjunctive tool for better assessment of complex root canal systems. PMID:26015823

  13. From automatic control of vessels designed to operate in offshore conditions to automatic control of a large barge convoy in a river/channel: lessons learned; Do controle automatico de embarcacoes projetadas para condicoes operacionais de offshore para o controle automatico de um grande comboio de barcacas em um rio/canal: licoes aprendidas

    Energy Technology Data Exchange (ETDEWEB)

    Pontes, Anselmo Carvalho [Symmetry Ltda., Rio de Janeiro, RJ (Brazil); Santos, Edson Mesquita do [Marinha do Brasil, Rio de Janeiro, RJ (Brazil)

    2008-07-01

    The waterway transportation sector, despite its problems and bottlenecks, is continually seeking alternatives to improve its operations. With goals of increased efficiency, safety and cost reduction, the sector is modernizing and acquiring new technology. The Dynamic Position control system for a large barge convoy is one of the new technology highlights. This innovation may make development in the Brazilian waterway transportation sector feasible by permitting navigational safety and greater flexibility in transport and distribution not only for mined products but for petroleum and its derivatives. This paper presents the development process of The Dynamic Position control system for a large barge convoy in the Parana-Paraguay River, for Rio Tinto Mining Company. The hydrodynamics effects in a river are quite different than those of the traditional offshore environment. The degree of difficulty involved in solving this problem is highly dependent on a ship's characteristics, which can be analyzed in function of their hydrodynamic coefficients. Model tests in towing tanks were made to adjust the hydrodynamic coefficients and characteristics of the thrusters. The choice of the 'backstepping' control law and observer (state estimator) presented in this paper is a result of these particular conditions. The authors point out the advantage of using this technique, since all the properties of the coefficients of the hull, propeller(s) and thruster(s) have already been tested and tuned and are able to make a reliable set-up that optimizes navigation in restricted waterways. (author)

  14. External ear canal cholesteatoma after ventilation tube insertion and mastoidectomy

    Directory of Open Access Journals (Sweden)

    Đerić Dragoslava

    2012-01-01

    Full Text Available Introduction. Etiopathogenetically, there are two types of chollesteatomas: congenital, and acquired. Numerous theories in the literature try to explain the nature of the disease, however, the question about cholesteatomas remain still unanswered. The aim of the study was to present a case of external ear canal cholesteatoma (EEC developed following microsurgery (ventilation tube insertion and mastoidectomy, as well as to point ant possible mechanisms if its development. Case report. A 16-yearold boy presented a 4-month sense of fullness in the ear and otalgia on the left side. A year before, mastoidectomy and posterior atticotomy were performed with ventilation tube placement due to acute purulent mastoiditis. Diagnosis was based on otoscopy examination, audiology and computed tomography (CT findings. CT showed an obliterative soft-tissue mass completely filled the external ear canal with associated erosion of subjacent the bone. There were squamous epithelial links between the canal cholesteatoma and lateral tympanic membrane surface. They originated from the margins of tympanic membrane incision made for a ventilation tube (VT insertion. The position of VT was good as well as the aeration of the middle ear cavity. The tympanic membrane was intact and of normal appearance without middle ear extension or mastoid involvement of cholesteatoma. Cholesteatoma and ventilation tube were both removed. The patient recovered without complications and shortly audiology revealed hearing improving. Follow-up 2 years later, however, showed no signs of the disease. Conclusion. There could be more than one potential delicate mechanism of developing EEC in the ear with VT insertion and mastoidectomy. It is necessary to perform routine otologic surveillance in all patients with tubes. Affected ear CT scan is very helpful in showing the extent of cholesteatoma and bony defects, which could not be assessed by otoscopic examination alone.

  15. Modeling of Unsteady Flow through the Canals by Semiexact Method

    Directory of Open Access Journals (Sweden)

    Farshad Ehsani

    2014-01-01

    Full Text Available The study of free-surface and pressurized water flows in channels has many interesting application, one of the most important being the modeling of the phenomena in the area of natural water systems (rivers, estuaries as well as in that of man-made systems (canals, pipes. For the development of major river engineering projects, such as flood prevention and flood control, there is an essential need to have an instrument that be able to model and predict the consequences of any possible phenomenon on the environment and in particular the new hydraulic characteristics of the system. The basic equations expressing hydraulic principles were formulated in the 19th century by Barre de Saint Venant and Valentin Joseph Boussinesq. The original hydraulic model of the Saint Venant equations is written in the form of a system of two partial differential equations and it is derived under the assumption that the flow is one-dimensional, the cross-sectional velocity is uniform, the streamline curvature is small and the pressure distribution is hydrostatic. The St. Venant equations must be solved with continuity equation at the same time. Until now no analytical solution for Saint Venant equations is presented. In this paper the Saint Venant equations and continuity equation are solved with homotopy perturbation method (HPM and comparison by explicit forward finite difference method (FDM. For decreasing the present error between HPM and FDM, the st.venant equations and continuity equation are solved by HAM. The homotopy analysis method (HAM contains the auxiliary parameter ħ that allows us to adjust and control the convergence region of solution series. The study has highlighted the efficiency and capability of HAM in solving Saint Venant equations and modeling of unsteady flow through the rectangular canal that is the goal of this paper and other kinds of canals.

  16. Study on congenital microtia and atresia after external canal plasty

    International Nuclear Information System (INIS)

    In treating congenital microtia and atresia, we conduct simultaneous external canal plasty, tympanoplasty, and auricle elevation with plastic surgeons about 6 months after auricleplasty by only plastic surgeons. The results are good both cosmetically and functionally. We report 13 cases in which hearing did not improve satisfactorily after surgery using postoperative high-resolution computed tomography (HRCT) of the temporal bone. Lateral healing was seen in 9 (69%), new bone proliferation in 3 (23%), malpositioning of a cartilage block in 2 (15%), and both lateral healing and malpositioning of a cartilage block in 1 (7.6%). (author)

  17. Contaminated sediment removal from a spent fuel storage canal

    Energy Technology Data Exchange (ETDEWEB)

    Geber, K R

    1993-01-01

    A leaking underground spent fuel transfer canal between a decommissioned reactor and a radiochemical separations building at the Oak Ridge National Laboratory (ORNL) was found to contain RCRA-hazardous and radioactive sediment. Closure of the Part B RCRA permitted facility required the use of an underwater robotic vacuum and a filtration-containment system to separate and stabilize the contaminated sediment. This paper discusses the radiological controls established to maintain contamination and exposures As Low As Reasonably Achievable (ALARA) during the sediment removal.

  18. Conflict analysis and management alternative for the Manayunk Canal

    International Nuclear Information System (INIS)

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

  19. Root canal retained restorations: 3. Root-face attachments.

    Science.gov (United States)

    Dummer, P M; Edmunds, D H; Gidden, J R

    1990-10-01

    It has been common practice for many years to use retained roots to provide support and stability for partial or full dentures. The retention of such overdentures is greatly enhanced if the remaining roots are modified and restored with posts and root-face attachments. The final article in this series on root canal retained restorations classifies and describes some of the root-face attachments currently available, and also describes a number of prefabricated post systems with integral overdenture attachments. Guidelines for clinical and laboratory procedures are given. PMID:2097234

  20. Interferencia co-canal en redes WiMax

    OpenAIRE

    Durán Vicente, María Isabel

    2012-01-01

    El objetivo principal de este proyecto es estudiar las redes WIMAX para determinar las prestaciones de la red cuando se da una situación en la que existe interferencia co-canal. Este tipo de interferencia, al igual que otras, ocasionará una pérdida de prestaciones que será lo que se evalúe a través de diversas simulaciones en distintos escenarios. En el primer capítulo se hará una descripción del estándar comentando todos sus aspectos relevantes, poniendo especial énfasis en los puntos que so...

  1. COMPARISON OF THE BIOCOMPATIBILITY OF DIFFERENT ROOT CANAL IRRIGANTS

    OpenAIRE

    João Eduardo Gomes-Filho; Kamila Guilherme Aurélio; Mariana Machado Teixeira de Moraes Costa; Pedro Felício Estrada Bernabé

    2008-01-01

    The purpose of this study was to compare the reaction of rat subcutaneous connective tissue to 0.9% sterile saline, 2.5% sodium hypochlorite (NaOCl), 5.25% NaOCl and 2% chlorhexidine gluconate solution or gel. Six circles were demarcated on the dorsal skin of 24 male Wistar rats, leaving 2 cm between each circle. Using a syringe, 0.1 mL of each root canal irrigant was injected subcutaneously into 5 circles. In the 6th circle, the needle of an empty syringe was introduced into the skin, but no...

  2. Sistema de máquinas para revestir canales magistrales

    OpenAIRE

    Julián Remberto Sánchez Alonso; Eusebio Ramón González Utria; José Martínez Grave de Peralta; Johann Mejías Brito

    2010-01-01

    El trabajo consistió en la concepción, diseño, construcción y prueba de un sistema de máquinas para el revestimiento mecanizado de taludes de canales magistrales del tipo "Bio - La Rioja", su importancia está basada en la necesidad de acelerar las obras de la voluntad hidráulica y el programa alimentario. El método mecanizado de revestimiento incrementa el rendimiento respecto al tradicional, además contribuye al ahorro de materiales, mano de obra y uso de equipos, en particular de combustibl...

  3. Incidence of low birth weight among Love Canal residents.

    Science.gov (United States)

    Vianna, N J; Polan, A K

    1984-12-01

    The incidence of low birth weight among white live-born infants from 1940 through 1978 was studied in various sections of the Love Canal. A statistically significant excess was found in the historic swale area from 1940 through 1953, the period when various chemicals were dumped in this disposal site. Potential confounding factors such as medical-therapeutic histories, smoking, education, maternal age, birth order, length of gestation, and urban-rural difference did not appear to account for this observation. Low birth weight rates were comparable to those of upstate New York from 1954 through 1978, the period when there was no deposition of chemical wastes.

  4. Impact of improved operation and maintenance on cohesive sediment transport in Gezira Scheme, Sudan

    OpenAIRE

    Osman, I.S.E.

    2015-01-01

    Summary Efficient operation and maintenance of irrigation schemes are needed for improving the hydraulic performance of the canals, enhancing the crop yields and insuring sustainable production. There is a great need to enhance the researches and for a variety of tools such as water control and regulation equipment, decision support systems, as well as field surveys and valuation techniques. Water management becomes difficult when dealing with sediment transport in irrigation canals. Most of ...

  5. The clinical analysis on the effects of different difficulty in root canal preparation%不同难度根管预备效果的临床分析

    Institute of Scientific and Technical Information of China (English)

    王瑞; 高小洁; 孙拓祺; 谭红; 黄定明

    2011-01-01

    Objective To investigate the effects of root canal preparation treated by endedontists of different levels in different difficulty associated with the root canal anatomy factors. Methods Totally 422 teeth with 901 root canals were randomly selected from the Conservative Dentistry Department, West China Stomatology Hospital,and these teeth were respectively treated by junior specialist postgraduates, senior specialist postgraduates and endodontic specialists. Grading criteria of root canal risk factor and root canal therapy difficulty assessment were found based on 6 items: Tooth type, working length, root curvature, calcification, number of canals, and the previous endodontic treatment. The effects of root canal preparation with different difficulty in different groups were analyzed with R×C Chi-square test. Results Success rates of root canal preparation in junior group and senior group during three difficulty groups were statistically different (P<0.05), and the root canal therapy difficulty group Ⅰ >group Ⅱ > group Ⅲ. The operator factors in root canal therapy difficulty group Ⅰ and group Ⅱ were not significantly different (P>0.05). But in root canal therapy difficulty group Ⅲ, the endedontic specialist group have highest success rate in root canal preparation. Conclusion The cases of root canal treatment should be treated by endodontist of corresponding level according to the difficulty. In difficult cases, endedontic specialist can provide better root canal preparation result.%目的 分析不同层次医生对与根管解剖因素相关的不同难度根管病例的接诊情况及其根管预备效果.方法 随机选取2005年3月-2006年4月间四川大学华西口腔医院牙体牙髓病科低年级专科研究生、高年级专科研究生以及专科医生分别接诊的共计422颗患牙901个根管为研究对象,按照牙位、工作长度、弯曲度、钙化度、根管数目及根管治疗史建立根管治疗解剖危险因

  6. 倒敞法结合2 种机用镍钛锉预备重度弯曲后牙根管的应用研究%A clinical research of two Ni-Ti rotary instruments on severe bending molar root canal preparation by reverse flaring technique

    Institute of Scientific and Technical Information of China (English)

    卢山; 谭曲波; 梁非照; 郭宏剑; 陶艳萍; 黎钢; 何燕华

    2009-01-01

    Objective: To evaluate the treatment efficacy of reverse flaring technique applied by two rotary instruments, Hero 642 and ProTaper, on complicated molar root canal preparation. Methods: 100 molars with curved root canals (maximum curved angle ≥25 degrees) suffered from pulpitis or periapicities were randomly divided into two groups. In experimental group reverse flaring technique was applied by rotary instruments while in control group reverse flaring technique was not adopted. 50 experimental teeth with curved canals were operated with K files, Hero 642 and ProTaper in sequence. Lateral condensation obturation method was utilized in both groups. Root canal preparation and obturation efficiency were evaluated by X-ray, root canal preparation time and complication incidence (1 year follow-up rate was 95%). Results: Reverse flaring technique applied by Hero 642 and ProTaper Ni-Ti rotary instruments on complicated (curved) root canal preparation in group A demonstrated better root canal coning and smoothness, without instrument fractures, while instrument fractures occurred in control group. Significant difference was found in exact root canal obturation rate and not enough full rate, root canal smoothness and postoperative pain between two groups(P0.05);充填恰充率、欠充率、流畅度、术后疼痛两者有显著性差异(P<0.05).结论: 倒敞法结合Hero 642和ProTaper机用镍钛锉预备重度弯曲后牙根管,成形、根充效果好,并发症少,最大限度发挥了各自优点,是预备重度弯曲后牙根管值得推广应用的有效方法.

  7. 牙科显微镜与根管治疗%Dental microscope and root canal therapy

    Institute of Scientific and Technical Information of China (English)

    詹福良

    2013-01-01

    在过去的20多年里,牙科领域在技术方法、材料和设备上有许多令人鼓舞的进展。牙体牙髓专业也同样有很多革命性突破。根管治疗是牙体牙髓的最基本操作,治疗时的照明和放大是两个最关键的影响因素。牙科显微镜的应用使根管治疗进入了精细时代。本文对牙科显微镜的发展及在牙体牙髓领域的应用做了较为详尽的介绍。%In the past twenty years,there are many en-couraging advances in dentistry,so are there in endodontics. As a basic operation in endodontic field,modern root canal therapy must be managed under magnification and illumina-tion. The use of dental microscope makes root canal therapy enter refining era. This article focused on the relationship be-tween endodontic operation and dental microscope.

  8. Otolith-Canal Convergence In Vestibular Nuclei Neurons

    Science.gov (United States)

    Dickman, J. David; Si, Xiao-Hong

    2002-01-01

    The current final report covers the period from June 1, 1999 to May 31, 2002. The primary objective of the investigation was to determine how information regarding head movements and head position relative to gravity is received and processed by central vestibular nuclei neurons in the brainstem. Specialized receptors in the vestibular labyrinths of the inner ear function to detect angular and linear accelerations of the head, with receptors located in the semicircular canals transducing rotational head movements and receptors located in the otolith organs transducing changes in head position relative to gravity or linear accelerations of the head. The information from these different receptors is then transmitted to central vestibular nuclei neurons which process the input signals, then project the appropriate output information to the eye, head, and body musculature motor neurons to control compensatory reflexes. Although a number of studies have reported on the responsiveness of vestibular nuclei neurons, it has not yet been possible to determine precisely how these cells combine the information from the different angular and linear acceleration receptors into a correct neural output signal. In the present project, rotational and linear motion stimuli were separately delivered while recording responses from vestibular nuclei neurons that were characterized according to direct input from the labyrinth and eye movement sensitivity. Responses from neurons receiving convergent input from the semicircular canals and otolith organs were quantified and compared to non-convergent neurons.

  9. Semicircular Canals Circumvent Brownian Motion Overload of Mechanoreceptor Hair Cells.

    Directory of Open Access Journals (Sweden)

    Mees Muller

    Full Text Available Vertebrate semicircular canals (SCC first appeared in the vertebrates (i.e. ancestral fish over 600 million years ago. In SCC the principal mechanoreceptors are hair cells, which as compared to cochlear hair cells are distinctly longer (70 vs. 7 μm, 10 times more compliant to bending (44 vs. 500 nN/m, and have a 100-fold higher tip displacement threshold (< 10 μm vs. <400 nm. We have developed biomechanical models of vertebrate hair cells where the bundle is approximated as a stiff, cylindrical elastic rod subject to friction and thermal agitation. Our models suggest that the above differences aid SCC hair cells in circumventing the masking effects of Brownian motion noise of about 70 nm, and thereby permit transduction of very low frequency (<10 Hz signals. We observe that very low frequency mechanoreception requires increased stimulus amplitude, and argue that this is adaptive to circumvent Brownian motion overload at the hair bundles. We suggest that the selective advantage of detecting such low frequency stimuli may have favoured the evolution of large guiding structures such as semicircular canals and otoliths to overcome Brownian Motion noise at the level of the mechanoreceptors of the SCC.

  10. Semicircular Canals Circumvent Brownian Motion Overload of Mechanoreceptor Hair Cells.

    Science.gov (United States)

    Muller, Mees; Heeck, Kier; Elemans, Coen P H

    2016-01-01

    Vertebrate semicircular canals (SCC) first appeared in the vertebrates (i.e. ancestral fish) over 600 million years ago. In SCC the principal mechanoreceptors are hair cells, which as compared to cochlear hair cells are distinctly longer (70 vs. 7 μm), 10 times more compliant to bending (44 vs. 500 nN/m), and have a 100-fold higher tip displacement threshold (< 10 μm vs. <400 nm). We have developed biomechanical models of vertebrate hair cells where the bundle is approximated as a stiff, cylindrical elastic rod subject to friction and thermal agitation. Our models suggest that the above differences aid SCC hair cells in circumventing the masking effects of Brownian motion noise of about 70 nm, and thereby permit transduction of very low frequency (<10 Hz) signals. We observe that very low frequency mechanoreception requires increased stimulus amplitude, and argue that this is adaptive to circumvent Brownian motion overload at the hair bundles. We suggest that the selective advantage of detecting such low frequency stimuli may have favoured the evolution of large guiding structures such as semicircular canals and otoliths to overcome Brownian Motion noise at the level of the mechanoreceptors of the SCC. PMID:27448330

  11. Various Strategies for Pain-Free Root Canal Treatment

    Science.gov (United States)

    Parirokh, Masoud; V. Abbott, Paul

    2014-01-01

    Introduction: Achieving successful anesthesia and performing pain-free root canal treatment are important aims in dentistry. This is not always achievable and therefore, practitioners are constantly seeking newer techniques, equipments, and anesthetic solutions for this very purpose. The aim of this review is to introduce strategies to achieve profound anesthesia particularly in difficult cases. Materials and Methods: A review of the literature was performed by electronic and hand searching methods for anesthetic agents, techniques, and equipment. The highest level of evidence based investigations with rigorous methods and materials were selected for discussion. Results: Numerous studies investigated to pain management during root canal treatment; however, there is still no single technique that will predictably provide profound pulp anesthesia. One of the most challenging issues in endodontic practice is achieving a profound anesthesia for teeth with irreversible pulpitis especially in mandibular posterior region. Conclusion: According to most investigations, achieving a successful anesthesia is not always possible with a single technique and practitioners should be aware of all possible alternatives for profound anesthesia. PMID:24396370

  12. Water bolus for electron irradiation of the ear canal

    International Nuclear Information System (INIS)

    Purpose: To demonstrate that water bolus in the external ear can decrease the dose inhomogeneity caused by auricular surface irregularities when the ear is in an electron-beam field. Methods and Materials: Three-dimensional (3D) dose distributions with and without water bolus in the external ear were calculated for a representative patient. The electron dose calculations were made using the Hogstrom pencil beam algorithm as implemented in 3D by Starkschall. To demonstrate the use of water bolus in the ear clinically, the case of a patient with squamous carcinoma of the concha who was treated with electrons is presented. Results: Water bolus markedly lessens the dose heterogeneity caused by the surface irregularities of the ear and the air in the external auditory canal. In the test case, the maximum dose was reduced by 25% using this technique. Conclusion: When the ear is in an electron beam field, warm water should be placed in the external auditory canal and concha. This maneuver may reduce the incidence of auricular complications that occur after electron-beam therapy

  13. Entrevista a Jordi Canal para Historia 2.0

    Directory of Open Access Journals (Sweden)

    Miguel Darío Cuadros Sánchez

    2012-07-01

    Full Text Available Jordi Canal es profesor y director de estudios en la École des Hautes Études en Sciences Sociales (EHESS de Paris, uno de los grandes especialistas en historia contemporánea. Cosmopolita y trilingüe (español, catalán y francés, su bibliografía reciente incluye obras de referencia, como autor o editor, «Los éxodos políticos en España, siglos XV-XX» (2007, «Una historia política del carlismo, 1876-1939» (2006. En el marco del XVII Congreso de la Asociación de Colombianista y la presentación de una conferencia sobre historia política en la Maestría de Historia de la Universidad Industrial de Santander, el profesor Jordi Canal visitó la ciudad de Bucaramanga del 3 al 5 a de agosto del presente año y tuvo la amabilidad de brindar sus opiniones a la revista Historia 2.0.

  14. Hydrogeology of the Canal Creek area, Aberdeen Proving Ground, Maryland

    Science.gov (United States)

    Oliveros, J.P.; Vroblesky, D.A.

    1989-01-01

    Geologic and borehole geophysical logs made at 77 sites show that the hydrogeologic framework of the study area consists of a sequence of unconsolidated sediments typical of the Coastal Plain of Maryland. Three aquifers and two confining units were delineated within the study area. From the surface down, they are: (1) the surficial aquifer; (2) the upper confining unit; (3) the Canal Creek aquifer; (4) the lower confining unit; and (5) the lower confined aquifer. The aquifer materials range from fine sand to coarse sand and gravel. Clay lenses were commonly found interfingered with the sand, isolating parts of the aquifers. All the units are continuous throughout the study area except for the upper confining unit, which crops out within the study area but is absent in updip outcrops. The unit also is absent within a Pleistocene paleochannel, where it has been eroded. The surficial and Canal Creek aquifers are hydraulically connected where the upper confining unit is absent, and a substantial amount of groundwater may flow between the two aquifers. Currently, no pumping stresses are known to affect the aquifers within the study area. Under current conditions, downward vertical hydraulic gradients prevail at topographic highs, and upward gradients typically prevail near surface-water bodies. Regionally, the direction of groundwater flow in the confined aquifers is to the east and southeast. Significant water level fluctuations correspond with seasonal variations in rainfall, and minor daily fluctuations reflect tidal cycles. (USGS)

  15. The fit of tapered posts in root canals luted with zinc phosphate cement : A histological study

    NARCIS (Netherlands)

    Schmage, P; Ozcan, M; McMullan-Vogel, C; Nergiz, [No Value; Özcan, Mutlu; Nergiza, Ibrahim

    2005-01-01

    Objectives. Stress transmission to the root through passive fitting dental posts is partly influenced by the thickness of the cement layer between the post and the prepared root canal surface as well as the fit of the post in the root canal. The objective of this study was to compare the cement gap

  16. The fit of tapered posts in root canals luted with zinc phosphate cement: A histological study

    NARCIS (Netherlands)

    Schmage, P.; Ozcan, M.; McMullan-Vogel, C.; Nergiz, I.

    2005-01-01

    Objectives. Stress transmission to the root through passive fitting dental posts is partly influenced by the thickness of the cement layer between the post and the prepared root canal surface as well as the fit of the post in the root canal. The objective of this study was to compare the cement gap

  17. Hydrodynamic detection by cupulae in a lateral line canal: functional relations between physics and physiology.

    NARCIS (Netherlands)

    van Netten, Sietse M

    2006-01-01

    In the present review, signal-processing capabilities of the canal lateral line organ imposed by its peripheral architecture are quantified in terms of a limited set of measurable physical parameters. It is demonstrated that cupulae in the lateral line canal organ can only partly be described as can

  18. A non-iterative cascaded predictive control approach for control of irrigation canals

    NARCIS (Netherlands)

    Negenborn, R.R.; Sahin, A.; Lukszo, Z.; De Schutter, B.; Morari, M.

    2009-01-01

    Irrigation canals transport water from water sources (such as large rivers and lakes) to water users (such as farmers). Irrigation canals are typically very large in nature, covering vast geographical areas, and involving a significant number of control actuators, such as pumps, gates, and locks. Th

  19. An evaluation of the influence of passive ultrasonic irrigation on the seal of root canal fillings

    NARCIS (Netherlands)

    van der Sluis, L. W. M.; Shemesh, H.; Wu, M. K.; Wesselink, P. R.

    2007-01-01

    Aim To evaluate the influence of passive ultrasonic irrigation (PUI) on the seal of root canal fillings. Methodology A total of 40 mandibular premolars were distributed equally into two groups and the root canals were cleaned and shaped; they were then filled with gutta-percha and AH26 (sealer) usin

  20. Effect of needle insertion depth and root canal curvature on irrigant extrusion ex vivo

    NARCIS (Netherlands)

    Psimma, Z.; Boutsioukis, C.; Kastrinakis, E.; Vasiliadis, L.

    2013-01-01

    Introduction The aim of this study was to evaluate the effect of needle type and insertion depth, apical preparation size, and root canal curvature on irrigant extrusion by using a recently introduced method. Methods Sixteen human teeth with a straight root canal (group A) and 16 with a moderatel