Role of Endodontic Biofilms

Biofilms are highly structured, hydrated microbial communities containing sessile cells embedded in a self-produced extracellular polymeric matrix (containing polysaccharides, DNA and other components). The formation of biofilms might facilitate certain survival and virulence characteristics under some situations. Several mechanisms have been postulated in the biofilm antimicrobial resistance, which includes; slow penetration of the antimicrobial agent into the biofilm, changes in the chemical micro-environment within the biofilm leading to zones of slow or no growth, adaptive stress responses and presence of a small population of extremely resistant “persister” cells. Biofilm biology has become an expanding field of research and the knowledge accumulated suggests that organisms growing in biofilms develop properties different to those dwelling in the planktonic stage. This review article covers the concept of biofilms and its role in endodontic infections.

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Clinical Tips

For more accurate location of inferior alveolar nerve block injection, we can estimate it from a good quality panoramic x-Ray (OPG) by observing the tram lines traces of the inferior alveolar canal till it starts from the mandibular foramen and relate this to the level of the lower posterior dentition or the upper posterior dentitions. In case it was higher up the ramus, that needs giving the injection little higher than usual the technique is quiet easy, fast but giving surprising results. We all know that the signs and symptoms of total failure of IAN block is the complete absence of any numbness from both the lip and the tongue is the injection side confirmed by objective tests i.e., by the dentist and partial failure will be presented by numbness only in the tongue side Figure: 1,2 shows how this could be

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Management of Neglected Severe Early Childhood Caries in a Six Year Old Female Child: A Three Year Follow Up

Early childhood caries is a virulent form of dental caries, characterized by an overwhelming infectious challenge associated with unusual dietary practices. This case report is of a child with severely mutilated deciduous teeth and carious lesion affecting smooth surfaces of permanent teeth. Following caries risk assessment; the patient was educated in relation to oral hygiene practices and treated with latest techniques to facilitate eruption guidance for permanent teeth. So this paper emphasizes on multidisciplinary management and treatment of severe Early Childhood Caries (S-ECC).

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Middle Mesial Canal in Mandibular First Molars: A Micro-CT Study

Objectives: The aim of this study was to investigate the presence and the incidence of a third canal in the mesial root of permanent mandibular first molars by using microcomputed tomography (micro-CT) and to describe the morphology of mandibular first molar’s root canal anatomy.
Methods: A total of 100 extracted mandibular first molars were randomly collected. Teeth were scanned by using micro-CT device (SkyScan 1074, Aartselaar, Belgium). These images were reconstructed three-dimensionally by using software NRecon (SkyScan 1074, Kontich, Belgium). After constructing, three-dimensional images exhibiting the shape of the roots were analyzed by using 3D-Doctor software programme (v.3.5 Able Software Corp, Lexington,MA). Thereafter, the number of the middle mesial canals, were evaluated.
Results: The results of this study indicate that a middle mesial canal present in 12% of mandibular first molars. Among these middle mesial canals two were independent canals, ten were confluent canals.
Conclusion: Micro-CT is a promising research tool for three dimensional evaluation of tooth morphology and provides detailed information on the configuration of root canals. In this study, 12% of mandibular first molars had a middle mesial canal which is significantly important from a clinical point of view. The possibility of additional canal in the mesial root should be anticipated in mandibular first molars.

Endodontics: Current Trends, New Horizons…

The utilization of new technological advances and materials in clinical endodontics is heading on a new era “ahead of the curve”. The outline of endodontic practice and clinical concepts are changing rapidly. The use of calcium hydroxide as an intra-canal by almost 80% of the general practitioners and endodontists for necrotic pulps and even for the routine dressings has replaced the old classics and increased the success rate with the introduction of efficient rotary engines, systems and various rotary tips, manual preparation has became less used and is the preferred technique in the endodontic offices. Routine use rubber-dam use in the world and saliva isolation techniques has contributed to aseptic conditions very much. Newer anesthetic techniques like Gow-Gates, Akinosi, intra pulpal techniques and devices the pain management in endodontics has improved. Electronic apex locators, introduction of mineral trioxide aggregate (MTA), IRM, the use of very sophisticated adhesives for restorations and glass-ionomers for coronal sealing based on the studies show the importance of the preventing coronal leakage following the root canal treatments for success, new condensation and compaction techniques has decreased the endodontic failures.

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Land Zoning: Concept and its Urgency in Bangladesh

Bangladesh is a least developed South Asian country and its economy is based on agriculture. Among the natural resources, land and soil are the key resource for agriculture. We have to ensure its proper utilization for ensuring food security without decreasing its extent and quality.
In Bangladesh the natural resources especially the land resources of an area is used for multiple purposes, which have strong influences on the socio-economic development of the area. Due to huge population pressure land resources are under continuous human and natural interventions so its land use is naturally diverse and complex. The land resources of an area is intensively used for agriculture, settlements, forests, water bodies and fisheries, salt production, industries and infrastructural development, tourism, preservation and management of environmentally important and special areas.
Land and soil resources are vital and limiting resource for agriculture. The encroachment on agricultural land is a pressing problem in the rapidly growing areas of our country. Cultivable land has reduced from 9.72 million hectare (1991) to 8.52 hectares (2011). This is alarming for an over populated country like Bangladesh. Food security of the country would be threatened if land and soil resources are degraded and cultivated area is reduced at present rate. To arrest negative balance land zoning is a must for sustainable agricultural development of the country.
Secondary data were obtained from publications of Soil Resource Development Institute (SRDI) and Department of Land Records (DLR). They provided spatial information pertinent to land zoning in Kaliganj Upazila. All maps were constructed in ARC/Info and exported into shape file formats compatible with ArcView 3.2. All themes were projected in the LCC having a scale of 1 : 50,000. Current land use data were collected by field survey which provided an opportunity to develop a working relationship with land use, topography and landscape characteristics.
The ultimate output of this study was a map showing the distributions of the various land zones. The Kaliganj Upazila comprises of about 21,316 ha land surface. Agriculture zone, Forest zone and Aquaculture zone accounts for 5,247 ha, 8,760 ha and 5,871 ha respectively. About 858 ha area accounts for Commercial and Residential Zone and about 583 ha for Water bodies including rivers. The proposed urban zone accounts for 715 ha.

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Technomic Analysis of Biodiesel Production from Jatropha curcas: Shrub Cultivability, Consecutive-Competitive Reactions, Centrifugal Separation and Optimization

Advances in sequencing of genomes have leaded to the promise of genetically modified fuel crop such Jatropha curcas that is used to obtain Jatropha oil. The gene regulation via Ribosome inhibiting Protein in the shrub has been studied using transfection of clones of curcin genes found in Jatropha curcas in other plants. This can lead to better cultivability of the Shrub and higher yield of Jatropha oil. NGS, Next-Generation Sequencing machines available commercially are tabulated. The triglycerides in Jatropha oil can be transesterified using excess methanol in the presence of catalyst or excess methanol into biodiesel and glycerol. The glycerol can be sold as by-product. The kinetics of consecutive-competitive reactions during methanolysis of triglycerides with intermediates such as diglyceride, monoglyceride are modeled. The model solutions assuming irreversible simple first order kinetics were obtained using the method of Laplace transforms. Although biodiesel forms in each consecutive step under some conditions of reaction rate ratios ω and κ the yield of glycerol are seen to be higher than that of biodiesel. This can be called “cross-over” and can be seen in the illustrations shown as prototypical examples. The operating cost of separating biodiesel from glycerol using centrifuge can be obtained from computer simulations of layer formation during shear flow. For optimal total cost there exists a yield of biodiesel where the process can be operated at.

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Analysis of Pressures on Nagarjuna Sagar Spillway

Availability of water is very important natural resource of a nation, which can be used for the development of the country. Dam is a type of hydraulic structure built across a river (or stream). At the back of this barrier; water gets collected, forming a pool of water. The side on which water gets collected is called the upstream side and the other side of the barrier is called the downstream side. The lake of water which is formed upstream is called reservoir. Thus a reservoir and a dam exist together. The present study area is on Nagarjunasagar Dam, the giant among the masonry dams across River Krishna in Telangana State. In the design of hydraulic structures, many problems of non uniform and unsteady flow, sediment motion, dispersion, density currents and cases with complicated geometry fully defy. Therefore experimental work on scale models is often the most efficient and sometimes indeed the only method for solving the problem. The experiment cannot be carried out on the full size hydraulic structures, which are proposed to be erected. It is then essential to construct a small scale replica of the structure and the tests are performed on it to obtain the desired information. An attempt has been made to find the solution to the problem encountered in Nagarjunasagar dam constructed across river Krishna in Nalgonda district, Telangana state by using the theory of physical model study. A hydraulic model study was conducted to evaluate the cavitation damage due to negative pressures in terms of their magnitudes and locations on the spillway of the dam due to the floods in 2009 using the model studies on it. The experiment was carried out for free flow and gated operations for various discharge conditions. The maximum negative pressures observed at pressure tube points in vent no 1 is 0.079 at P7 for 1/4th of maximum flood discharge for gated condition. The maximum negative pressures observed at pressure tube points in vent no 2 is 0.031 at P7 for 3/4th, half and 1/4th of maximum flood discharge for free flow condition. The maximum negative pressures observed at pressure tube points in vent no 3 is 0.031 at P2 for 3/4th of maximum flood discharge for both free flow and gated conditions and 1/2 and 1/4th of maximum flood discharge for gated condition.

Revisiting Feeding Systems in Postmodern Ruminant Agriculture: Challenging the TMR

This objective of this editorial article is to revisit the conventional concepts on feeding systems practiced in modern ruminant agriculture production. Total mixed ration (TMR) is a type of preparation that aims to ensure that a nutritionally balanced diet containing forage and concentrate is such uniformly mixed that any bout taken by the ruminant represents the diet calculated on paper. However, this definition is not met in more than many practical scenarios on-farm mainly due to carelessly adopted forage particle size, inappropriately chosen forage choice, inadequate dietary moisture, suboptimal feed items mixing, and considerable particle selection in the bunk.

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Molecular Markers for Smut Resistance in Mutated Population of Sugarcane Clone GT-54-9 through Amplified Fragment Length Polymorphism (AFLP)

Eight AFLP selective primer combinations were used to detect smut resistant markers in different sugarcane resistant and susceptible sugarcane mutants generated from sugarcane variety GT 54-9 using Gamma radiation. AFLP amplification using the eight primer pairs resulted in a total 390 scorable bands with an average of 48.75 bands per primer combination. The selective primer combination E-ACC/Tru-CTG was the only one able to distinguish between the resistant and susceptible mutants by the amplification of two bands ≈ 110-120 bp bands in resistant sugarcane mutants.

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