Nanoarchitectonics for High Adsorption Capacity Carboxymethyl Cellulose Nanofibrils-Based Adsorbents for Efficient Cu2+ Removal

In the present study, carboxymethyl cellulose nanofibrils (CMCNFs) with different carboxyl content (0.99–2.01 mmol/g) were prepared via controlling the ratio of monochloroacetic acid (MCA) and sodium hydroxide to Eucalyptus bleached pulp (EBP). CMCFs-PEI aerogels were obtained using the crosslinking reaction of polyethyleneimine (PEI) and CMCNFs with the aid of glutaraldehyde (GA). The effects of pH, contact time, temperature, and initial Cu2+ concentration on the Cu2+ removal performance of CMCNFs-PEI aerogels was highlighted. Experimental data showed that the maximum adsorption capacity of CMCNF30-PEI for Cu2+ was 380.03 ± 23 mg/g, and the adsorption results were consistent with Langmuir isotherm (R2 > 0.99). The theoretical maximum adsorption capacity was 616.48 mg/g. After being treated with 0.05 M EDTA solution, the aerogel retained an 85% removal performance after three adsorption–desorption cycles. X-ray photoelectron spectroscopy (XPS) results demonstrated that complexation was the main Cu2+ adsorption mechanism. The excellent Cu2+ adsorption capacity of CMCNFs-PEI aerogels provided another avenue for the utilization of cellulose nanofibrils in the wastewater treatment field.

Accidental Injection of EDTA Instead of Anesthesia Solution during Root Canal Treatment: Case Report

Summary Background/Aim: Many irrigation solutions are used during root canal treatment. It is unacceptable to confuse irrigation solutions with anesthetic solution and inadvertently inject the patient. After such an error, local and systemic serious complications can be seen in the patient. The purpose of this case report is to show how careless use of etilendiamin tetraacedic acid (EDTA) can result in important complications, and offer some treatment methods for curing symptoms resulting from such complications. Case Report: A 17% EDTA solution, was inadvertently injected in the buccal mucosa of a 20-year-old male during routine root canal treatment. Severe pain, bleeding and mucosal swelling occurred shortly after the injection. Irrigation with saline was performed by sliding the mucoperiosteal flap at the injection site. Then the flap was sutured primary. At the control one week later, there were no areas of necrosis in the patient, but ecchymosis occurred. Decalcified areas were not detected in dental volumetric tomography examination. Conclusions: The dentists must apply the precautions of EDTA irrigation solution during the root canal treatment and manage the treatment of this clinical complication.

Comparison of the accuracy of different electronic apex locators used in working length determination via changing of initial cleaning solutions

Aim: The aim of this study is to compare the accuracy of the Root ZX Mini, Raypex 6, E-Pex Pro, and Propex Pixi electronic apex locators by changing the initial cleaning solutions (NaOCl vs. EDTA). Methodology: Eighty mandibular premolar teeth were used. Radiographs were obtained from the mesio-distal and bucco-lingual angles for all teeth, and teeth with suspected external or internal root resorption and/or calcified canals were not included in the study. The true canal lengths of the teeth were determined with a precision of 0.01 mm with a stereomicroscope at x5 magnification by placing a #20 K-type canal file into the root canal. The samples were then embedded in freshly mixed alginate blocks up to the cemento-enamel junction. The coronal 1/3 was pre-enlarged with a Protaper SX instrument. Electronic apex finders (Root ZX Mini, Raypex 6, E-Pex Pro, Propex Pixi) specified on each tooth were used, and measurements were made by changing the initial solutions (NaOCl vs. EDTA). Distilled water was used between application of 5.25% NaOCl and 17% EDTA to prevent chemical interactions. Three measurements were taken for each tooth, and the average of these 3 measurements was taken as reference. The data obtained in this study were analyzed. Results: There were no statistically significant differences between the solutions in terms of the measurement values and actual length values found by each device (p>0.05). Although there were no statistically significant differences, the deviation from the actual measurement was greater when EDTA solution was used than when NaOCl solution was used. In addition, although the difference was not found to be statistically significant, the deviation from the actual measurement was found to be highest when the Root ZX mini device was used with NaOCl and EDTA solution. Conclusion: The results of this study showed that the difference in the initial washing solutions did not affect the EAL devices in making measurements close to the true length. How to cite this article: Tellioğlu Avcı GR, Kaya S Comparison of the accuracy of different electronic apex locators used in working length determination via changing of initial cleaning solutions. Int Dent Res 2021;11(Suppl.1):56-62. https://doi.org/10.5577/intdentres.2021.vol11.suppl1.9 Linguistic Revision: The English in this manuscript has been checked by at least two professional editors, both native speakers of English.

Comparative analysis of protocols for decellularization of corneal lenticular tissue

Shortage of donor corneas is a burning issue in ophthalmology. That is why there is a search for new alternative ways for treating corneal diseases. Decellularization technologies make it possible to create corneal tissue-engineered constructs that can adrress the issue of donor corneal shortage. Objective: to conduct a comparative analysis of effective methods for treating the corneal lenticula and to create an optimized and standardized decellularization protocol. Materials and methods. Corneal stromal lenticules obtained after ReLEx SMILE surgery were chosen for the study. Lenticule parameters: thickness 77–120 microns, diameter 6.5 mm. We used 3 protocols for the treatment of lenticules: 1) treatment with 1.5 M sodium chloride with nucleases (NaCl); 2) 0.1% SDS (SDS); 3) treatment with Trypsin-EDTA solution, followed by double washing in a hypotonic Tris buffer solution with nucleases (Trypsin-EDTA). Optical properties of lenticles were determined spectrophotometrically, where the samples before decellularization served as a control. Fluorescence imaging of nuclear material in the original cryosections was performed using Hoechst dye. The state of collagen fiber ultrastructure was assessed by scanning electron microscopy. The quantitative DNA content in fresh lenticules and in lenticules after treatment was analyzed. Results. All three decellularization protocols effectively removed nuclear and cellular material; the residual DNA content was < 50 ng/mg. However, the Trypsin-EDTA protocol led to significant damage to the extracellular matrix structure, which negatively affected the transparency of corneal tissue-engineered constructs. Transparency of samples for the NaCl protocol was close to native lenticules. Conclusion. To create a corneal tissue-engineered construct, NaCl decellularization protocols appear to be optimized and can be used to treat various corneal diseases.

Effect of three Mechanical Systems on Removal of Endotoxins from Asymptomatic Necrotic teeth with apical Periodontitis. (A randomized clinical trial)

Objective: The present study's objective was to evaluate the percentage of endotoxin diminution after mechanical instrumentation of asymptomatic necrotic teeth with apical periodontitis using three mechanical systems. Materials and Methods: One hundred and eighty patients between 18 and 65 participated in this research. Thirty-five of 140 teeth were selected for the four enlargement techniques. Control group, TFA, WOG, and PTN groups received final flushing with 6oC 17% EDTA solution gently administered to the WL through a cold (6oC) sterile metallic micro-cannula attached to the Endovac system (Kerr Endo) for one minute. Two samples of the canal were obtained using a sterile paper cone (size 30) introduced into the canal´s full length. Results: Results showed a statistically significant difference between the two groups in the percentage reduction of endotoxin levels (P-value <0.001, Effect size = 0.598). Group PTN showed a statistically significantly lower median % reduction in endotoxin quantities than Group WOG and TFA. Conclusion: Under this study's conditions, it can be concluded that the PTN system was more effective in endotoxins reduction in teeth with necrotic pulps. When the RCT is correctly instrumented, single visit RCT can be as effective as a multiple visit treatment.

Iron Stress in Crop Plants and Ways to Overcome it

Iron (Fe) stress is encountered by many crops in calcareous soils with pH above 8.0, which are abundant in India. Most of the times Fe stress goes unnoticed however anyway it affects yield. Aerobic rice and upland rice nurseries also exhibit Fe stress. In many cases frequent adequate irrigation solves the problem. In Fe deficient areas adequate organic manures must be applied, while preparing the field. Application of elemental S and S-containing fertilizers also helps in overcoming Fe stress in plants. In case of serious Fe-stress, ferrous sulphate or Fe-EDTA solution can be sprayed, which effectively overcome the Fe stress problem.

Comparative effect of Organic Amendments on Heavy Metals Adsorption in Soils and their Chemical properties

Incubation experiment was carried out to evaluate and compare effects of some selected amendments on adsorption of heavy metals in soils and their chemical properties. The experiment was CRD consisting of twelve treatment combinations with three replications. Soil samples were collected from the vicinity of Michael Okpara University of Agriculture and amended with organic amendments at the rate 20 ton/ha and heavy metals at the rate of 60 mg/kg, thoroughly mixed and wetted daily throughout the incubation period of 30 days. 0.05M EDTA solution was used to extract heavy metals. EDTA solution was filtered from soil with Whatman No1 filter paper. The soil was analyzed for chemical properties before and after experiment using standard procedures. Higher amount of heavy metals was extracted from the control soils than the amended soils indicating retention of heavy metals by the amendments. All the amendments were significantly (P<0.05) different in adsorption of copper with poultry manure having significantly (P<0.05) the highest adsorption capacity while the control had the least. Cocoa pod was significantly (P<0.05) higher on adsorption of lead with cow dung and poultry manure not being significantly (P>0.05) different from each other. Cow dung had the highest (P<0.05) on adsorption of zinc. Heavy metals combined with amendments had significant (P<0.05) effect on soil chemical properties. Most chemical properties were significantly (P<0.05) higher in soils treated with both amendments and heavy metals than soils treated with only heavy metals. Poultry manure, cocoa pod and cow dung appeared to have greater potential in removing heavy metals from soils.

Factors influencing DNA extraction from human skeletal remains: bone characteristic and total demineralization process

Background The extraction of DNA from skeletal remains with good quality and quantity is often challenging for the ability to generate DNA typing. Previous studies demonstrated the DNA extraction with total demineralization from fresh teeth and bones; however, the application in old skeletal remains has been less performed. To obtain good quality and high yield of DNA amount extracted from skeletal remains, the objective of this study was focused on exploring the factors influencing the total demineralization process to obtain developing effective methods. Results The concentration of EDTA was found to significantly enhance calcium chelation from the bone while pH of EDTA solution, incubation temperature, incubation time, and volume of EDTA solution were not significant. The optimal condition of total demineralization obtained from Placket-Burmann results represented good-quality DNA and the highest concentration of extracted DNA yield. Subsequently, the STR typing in some bone specimens processed by total demineralization process prior to DNA extraction was improved. Conclusions EDTA concentration was a key influencing factor on the total demineralization process to chelate calcium from human skeletal remains. The total demineralization process in old bone specimens probably improved the STR profiles.

Type 3 Dens Invagination. Diagnosis and comprehensive treatment

Object: researching the combination of endodontic and surgical treatment of a tooth with developing dens invaginatus pathology. Materials and methods. X-ray diagnostics were performed with the Veraview X800 Morita. Irrigation with sodium hypochlorite solution 5.25 % with additional ultrasound treatmentabd 17 % EDTA solution were used for drug treatment of invagination and the main channel. The root canal and invagination, due to a non-standard structure, were handled by VDW hand tools combined with the Aurum BLUE (Meta Biomed) machine tool. Constant obturation was performed by the method of vertical compaction «Siller-AN plus». During the surgical stage, Langer (Hu-Friedy) periodontal curettes, CL 8 (Hu-Friedy) curettage spoon, 141-004-31W Oval Spoon Excavator (Hu-Friedy) were used; access to the focus was formed using a piezo surgical spherical nozzle (CE 1, Piezotome Solo (Satelec, Akteon). 4583 Kohler needle holder was used for suturing, suture material – polypropylene 5.0. The bone defect was filled with xenogenic material BIO GEN cancellous size 2/3 mm, 2.0 (Biotek), the barrier membrane – BIOCOLLAGEN (Biotek), the periodontal defect was filled with BIO GEN mix (Biotek). Key words: dens invaginatus, tooth in tooth, endodontic treatment, bone augmentation, apical surgery.