scholarly journals Effect of Heat Softening versus Ultrasonic Removal of Root-End Gutta-Percha on the Quality of Root-End Preparation for Endodontic Microsurgery

Scanning ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Zhiting Ling ◽  
Ziting Zheng ◽  
Yuting Zeng ◽  
Lifang Jiang ◽  
Yuan Wu ◽  
...  
Keyword(s):  
Root Apex ◽  
Root Surface ◽  
Preparation Time ◽  
Marginal Integrity ◽  
Endodontic Microsurgery ◽  
Gutta Percha ◽  
Wilcoxon Rank Sum Test ◽  
Time Required ◽  
End Resection

This study is aimed at comparing the efficacy of heat softening and ultrasonic removal of root-end gutta-percha during retrograde preparation for root apical microsurgery. Recently extracted single-rooted premolars ( n = 40 ) were prepared with standardized endodontically treated and root-end resection and then randomly divided into four groups that received root-end cavity preparation using four different instruments: a diamond-coated ultrasonic tip (AS3D; SACTEON, Paris, France), AS3D with the modified plugger of cordless heat carrier (MSE; B&L Biotech, Bala Cynwyd, PA, USA), stainless steel ultrasonic tip (Jetip-2; B&L Biotech, Bala Cynwyd, PA, USA), or Jetip-2 with MSE. The time required for root-end preparation was recorded. The root apex samples were examined by scanning electron microscopy to assess root surface microcracks and marginal integrity. The remnants of gutta-percha on the cavity walls were evaluated using a stereomicroscope. Statistical analysis was performed using Student’s t -test and Wilcoxon rank-sum test ( P < 0.05 ). Usage of MSE with Jetip-2 significantly reduced preparation time from 99.8 ± 6.8   s to 32.4 ± 1.0   s ( P = 0.009 ), the number of microcracks from 42 to 13 ( P = 0.036 ), and the remnants of gutta-percha from 80% to 20% ( P = 0.041 ). Similar results were observed for AS3D with MSE. The heat softening of MSE was effective in cleaning gutta-percha, thus greatly improving the efficiency of the root-end preparation, thereby producing a root-end cavity with fewer microcracks and better marginal integrity.

scholarly journals Evaluation of Root-End Preparation with Two Different Endodontic Microsurgery Ultrasonic Tips

Biomedicines ◽  
2020 ◽  
Vol 8 (10) ◽  
pp. 383
Author(s):  
Paulo J. Palma ◽  
Joana A. Marques ◽  
Margarida Casau ◽  
André Santos ◽  
Francisco Caramelo ◽  
...  
Keyword(s):  
Morphological Changes ◽  
Root Surface ◽  
Preparation Time ◽  
Significance Level ◽  
Marginal Integrity ◽  
Endodontic Microsurgery ◽  
Before And After ◽  
Time Requirements ◽  
Extensive Surface ◽  
End Resection

The aim of this study is to compare root-end preparation performed with two different ultrasonic tips—CVDentus and NSK—and respective time requirements. After root-end resection, 32 teeth were randomly divided in two groups, according to the ultrasonic tip used for root-end preparation. Preparation time was recorded. Photomicrographs were taken to assess the following parameters: root surface microcracking, marginal integrity and presence of debris. One ultrasonic tip from each group was analyzed through scanning electron microscopy before and after root-end preparation. The significance level was set at α = 0.05. Incidence of microcracks in both groups was 12.5%. Solely intracanal microcracking was found, consistently positioned within the widest side of the remaining dentine. No statistically significant differences were verified between both experimental groups regarding marginal integrity (p = 0.102) and preparation time (p = 0.780), whereas statistical differences (p = 0.003) were found concerning the presence of debris (the minimum registered score was mostly verified in CVDentus group). NSK tips showed major morphological changes, with extensive surface wear and noticeable loss of particles, which was not verified on CVDentus tips. Our findings suggest significant differences regarding root-end preparation walls quality, with CVDentus tips showing better results. Concerning microcracking, as well as preparation time and marginal integrity, both ultrasonic tips showed similar results. Qualitative analysis exposed NSK tips major morphological changes and wear after use, which was not verified on CVDentus tips.

Radiographic Assessment of Post-retained Crowns in an Adult Jordanian Population

2006 ◽  
Vol 7 (4) ◽  
pp. 29-36 ◽  
Author(s):  
Khaled Q. Al-Hamad ◽  
Mohamed Al-Omari ◽  
Ahed Al-Wahadni ◽  
Azmi Darwazeh
Keyword(s):  
Root Canal ◽  
Health Centre ◽  
Root Apex ◽  
Dental School ◽  
Radiographic Assessment ◽  
Endodontically Treated Teeth ◽  
Jordanian Population ◽  
Gutta Percha ◽  
Fixed Prosthodontics

Abstract Aim The objective of this study was to radiographically assess and compare the quality of post-retained crowns fabricated at the Dental Health Centre of the Jordan University of Science & Technology (JUST). Methods and Materials Study data were collected in 2002 from existing dental records for all patients receiving treatment with post-retained crowns between October, 1997 and June, 1999. The posts were assessed radiographically to evaluate various aspects of the quality of post-retained crowns. All 129 posts were fabricated in the dental school. Results The most-frequently restored teeth were the maxillary incisors (38.8%). Sixty-two percent of the posts were tapered, while 38% were parallel-sided. The mean length of the posts was 0.95 mm (SD 0.41) with a range between 0.22-2.85 mm. Caries was diagnosed radiographically in 10.8% of cases with lesions located on root surfaces in 64.3% of them, while 35.7% of lesions were within the root canal. Three posts (2.3%) were deviated from the line of the root canal in the mesio-distal plane. No evidence of root filling was found in 2.3% of the cases. In the remainder of teeth 15.5% had gutta percha extended to the radiographic apex of the tooth, while 59.7% fell 0.5-1 mm short of the radiographic apex. Gutta-percha was extruded beyond the apex in 22.5% of the teeth. Space between the end of the post and the root filling was found in 22.2%. The percentage of canals with apparently completely healthy periapical tissue was 51.2%. In the rest of the cases 34.8% had areas of radiolucency at or near the root apices and 14% demonstrated widening of the periodontal space around the root apex. Root resection had been completed in 2.3% cases. Signs of external resorption were apparent in one case (0.78%). Conclusion The standards of the treatment of the endodontically treated teeth made at the dental hospital were satisfactory but could be improved by a controlled academic supervisory environment and a strict scientific approach to fixed prosthodontics within the dental school. Citation Al-Hamad KQ, Al-Omari M, Al-Wahadni A, Darwazeh A. Radiographic Assessment of Post-retained Crowns in an Adult Jordanian Population. J Contemp Dent Pract 2006 September;(7)4:029-036.

An Attempt at a Rational Classification of the Principal Accelerators of Vulcanization. II. A Study of the Time Required for Vulcanization Giving the Maxima Physical Properties at Different Temperatures

1930 ◽  
Vol 3 (1) ◽  
pp. 38-50
Author(s):  
R. Thiollet ◽  
G. Martin
Keyword(s):  
Physical Properties ◽  
Prolonged Heating ◽  
Physical Quality ◽  
Gutta Percha ◽  
Different Temperatures ◽  
Time Required ◽  
Rational Classification

Abstract We have attempted to classify the principal accelerators of vulcanization according to their chief characteristics which are the following: (1) Time necessary for the fixation of mixtures at different temperatures. (2) Times required at different temperatures to obtain vulcanization giving the maxima physical properties. (3) Aging. The first of these 3 items has been treated in Caoutchouc et Gutta-Percha (April, 1929) and we have shown how accelerators can be classified by their “precocity” of action; that is to say, by the rapidity with which they “fix” mixtures at different temperatures. The mixture being fixed, vulcanization continues and the physical quality of the rubber improves. It thus reaches a maximum, then diminishes upon too prolonged heating. In this second study we have attempted to determine the following points: (1) At a given temperature, how long a period of vulcanization is required to impart to the mixtures their maxima physical properties? (2) Within the range of temperatures, which temperature gives the optima physical properties?

scholarly journals Correlation among Root Canal Configuration, Quality of Filling, and Its Sealability

2021 ◽  
Author(s):  
Ricardo Machado ◽  
Ricardo Koetz ◽  
Daniel Comparin ◽  
Luiz Rômulo Alberton ◽  
Fonseca Roberti Lucas da Garcia ◽  
...  
Keyword(s):  
Cross Sections ◽  
Root Canal ◽  
Root Apex ◽  
Root Canal Filling ◽  
Fluid Filtration ◽  
Gutta Percha ◽  
Spearman's Rho ◽  
Spearman’S Rho ◽  
Spearman Test

Abstract Objective The study aimed to evaluate the existence of possible correlations among root canal configuration, quality of filling, and its sealability. Materials and Methods Sixty human mandibular central incisors were selected for this study. The teeth were prepared with the Profile 04 system up to instrument 35/0.04 and irrigated with 2.5 mL of 2.5% sodium hypochlorite at each instrument change. Root canal filling was performed by the lateral compaction technique, using gutta-percha and an epoxy resin-based sealer (AH Plus) labeled with 0.1% Rhodamine B dye. Afterward, the specimens were submitted to fluid filtration tests to assess the sealability of the filling. Cross-sections were obtained at −3, −6, and −8 mm from the root apex and submitted to a metallographic treatment to determine the root canal configuration and the percentage of gutta-percha filled areas. The data were statistically analyzed by the Grubbs test. Pairs of correlations were analyzed by applying the Spearman test at a level of significance of 5%. Results No correlation was observed among the analyzed variables as follows: root canal configuration versus filling quality (Spearman’s rho = 0.031); filling quality versus sealability (Spearman’s rho = 0.219); and root canal configuration versus sealability (Spearman’s rho = 0.184). Conclusion The root canal configuration did not affect the quality of the filling and its sealability.

Heat Transfer Enhancement in Separation Process of Ethanol from Ethanol Water Mixture by Using Surfactants

2020 ◽  
pp. 9-14 ◽  
Author(s):  
Acharya Anil Ramchandra ◽  
R. Kadam ◽  
A. T. Pise
Keyword(s):  
Heat Transfer ◽  
Ammonium Chloride ◽  
Sodium Dodecyl ◽  
Water Mixture ◽  
Transfer Enhancement ◽  
Surface Tension Reduction ◽  
Surface Active Agents ◽  
Surface Active ◽  
Time Required

Here the investigations are done while distillation of ethanol-water mixture for separating ethanol from fermentation process. Focus is to study reduction in time required and hence saving in energy for the distillation process of ethanol-water mixture under the influence of surface-active agents (Surfactants). This novelty is from observation of these surfactants to enhance heat transfer rate because of surface tension reduction in aqueous solutions. SDS (Sodium Dodecyl Sulphate), NH4Cl (Ammonium Chloride) and SLBS (Sodium lauryl benzene sulphonate) surfactants in different concentration are experimented. The concentration of these surfactant is varied from 1700 ppm to 2800 ppm. This range is decided by observing critical micelle concentration of used surfactants. Results showed that time is reduced and hence energy consumption is also reduced. Results shown by NH4Cl are found to be more useful as it is ecofriendly surfactant which is not affecting ethanol-water mixture. Use of ammonium chloride as surfactant in distillation is actually useful to reduce energy without hampering the quality of process is the novelty of this work.

scholarly journals Public Awareness and Disaster Risk Reduction: Just-in-Time Networks and Learning

2008 ◽  
Vol 23 (3) ◽  
pp. 286-288 ◽  
Author(s):  
Ali Ardalan ◽  
Faina Linkov ◽  
Eugene Shubnikov ◽  
Ronald E. LaPorte
Keyword(s):  
Hurricane Katrina ◽  
Wide Spectrum ◽  
Public Awareness ◽  
Just In Time ◽  
Educational Levels ◽  
Hazard And Risk ◽  
Time Required ◽  
Expert Network ◽  
Core Materials

AbstractImproving public awareness through education has been recognized widely as a basis for reducing the risk of disasters. Some of the first disaster just-in-time (JIT) education modules were built within 3–6 days after the south Asia tsunami, Hurricane Katrina, and the Bam, Pakistan, and Indonesia earthquakes through a Supercourse. Web monitoring showed that visitors represented a wide spectrum of disciplines and educational levels from 120 developed and developing countries. Building disaster networks using an educational strategy seizes the opportunity of increased public interest to teach and find national and global expertise in hazard and risk information. To be effective, an expert network and a template for the delivery of JIT education must be prepared before an event occurs, focusing on developing core materials that could be customized rapidly, and then be based on the information received from a recent disaster. The recyclable process of the materials would help to improve the quality of the teaching, and decrease the time required for preparation. The core materials can be prepared for disasters resulting from events such as earthquakes, hurricanes, tsunamis, floods, and bioterrorism.

scholarly journals Safe On-Boat Resuscitation by Lifeguards in COVID-19 Era: A Pilot Study Comparing Three Sets of Personal Protective Equipment

2021 ◽  
pp. 1-7
Author(s):  
Roberto Barcala-Furelos ◽  
Cristian Abelairas-Gómez ◽  
Alejandra Alonso-Calvete ◽  
Francisco Cano-Noguera ◽  
Aida Carballo-Fazanes ◽  
...  
Keyword(s):  
Pilot Study ◽  
Cardiopulmonary Resuscitation ◽  
Severe Acute Respiratory Syndrome ◽  
Personal Protective Equipment ◽  
High Efficiency ◽  
Prehospital Care ◽  
Protective Equipment ◽  
Preparation Time

Abstract Introduction: On-boat resuscitation can be applied by lifeguards in an inflatable rescue boat (IRB). Due to Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-COV-2) and recommendations for the use of personal protective equipment (PPE), prehospital care procedures need to be re-evaluated. The objective of this study was to determine how the use of PPE influences the amount of preparation time needed before beginning actual resuscitation and the quality of cardiopulmonary resuscitation (CPR; QCPR) on an IRB. Methods: Three CPR tests were performed by 14 lifeguards, in teams of two, wearing different PPE: (1) Basic PPE (B-PPE): gloves, a mask, and protective glasses; (2) Full PPE (F-PPE): B-PPE + a waterproof apron; and (3) Basic PPE + plastic blanket (B+PPE). On-boat resuscitation using a bag-valve-mask (BVM) and high efficiency particulate air (HEPA) filter was performed sailing at 20km/hour. Results: Using B-PPE takes less time and is significantly faster than F-PPE (B-PPE 17 [SD = 2] seconds versus F-PPE 69 [SD = 17] seconds; P = .001), and the use of B+PPE is slightly higher (B-PPE 17 [SD = 2] seconds versus B+PPE 34 [SD = 6] seconds; P = .002). The QCPR remained similar in all three scenarios (P >.05), reaching values over 79%. Conclusion: The use of PPE during on-board resuscitation is feasible and does not interfere with quality when performed by trained lifeguards. The use of a plastic blanket could be a quick and easy alternative to offer extra protection to lifeguards during CPR on an IRB.

Cytological and histochemical characteristics of the axenic root surface of Alnus glutinosa

1986 ◽  
Vol 64 (10) ◽  
pp. 2216-2226 ◽  
Author(s):  
Yves Prin ◽  
Mireille Rougier
Keyword(s):  
Cell Wall ◽  
Root Hair ◽  
Root Hairs ◽  
Root Apex ◽  
Alnus Glutinosa ◽  
Root Surface ◽  
Infection Process ◽  
Root Cap ◽  
A Cell ◽  
Histochemical Tests

The aim of the present study was to investigate the Alnus root surface using seedlings grown axenically. This study has focused on root zones where infection by the symbiotic actinomycete Frankia takes place. The zones examined extend from the root cap to the emerging root hair zone. The root cap ensheaths the Alnus root apex and extends over the root surface as a layer of highly flattened cells closely appressed to the root epidermal cell wall. These cells contain phenolic compounds as demonstrated by various histochemical tests. They are externally bordered by a thin cell wall coated by a thin mucilage layer. The root cap is ruptured when underlying epidermal cells elongate, and cell remnants are still found in the emerging root hair zone. Young emerging root hairs are bordered externally by a cell wall covered by a thin mucilage layer which reacts positively to the tests used for the detection of polysaccharides, glycoproteins, and anionic sites. The characteristics of the Alnus root surface and the biological function of mucilage and phenols present at the root surface are discussed in relation to the infection process.

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