Removal of a Broken Instrument from a Tooth with Apical Periodontitis Using a Novel Approach

Instrument breakage during treatment can lead to serious complications and carries the risk of treatment failure. When a file breaks in the canal, bypassing or removal can be difficult and the long-term prognosis of the tooth may be compromised. Sometimes surgery may be indicated for removal of the broken segment. Often some part of the root cannot be cleaned because of blockage by the broken file. This report presents a specific approach in non-surgical removal of a broken file from a maxillary lateral incisor with a buccal sinus tract and a broken instrument in the apical third which was partially over extended into the periapical lesion. The broken file was accessed through the sinus tract and pushed into the canal. The canal was cleaned and shaped, filled with mineral trioxide aggregate (MTA). Conclusion: A sinus tract can be a specific path to reach the root tip and get access to remove the foreign materials pushed beyond the root canal space.Keywords: Apical Surgery; Broken Instrument; Nonsurgical Retreatmen

Treatment of Dens Invagination in a Maxillary Lateral Incisor: A Case Report

Dens invagination is a developmental anomaly requiring specific treatment approaches. Oehler's Type III dens in dente, extends into the root and perforates at the apical area or lateral surface of the root. In this case endodontic treatment of the invaginated tooth was carried out through the central lumen of the invagination with calcium hydroxide without manipulation of the main pulp canal, thereby leaving the tooth vital. The 18-month follow-up examinations were indicative of treatment success; the periapical lesion resolved completely and the tooth remained vital. Conclusion: Information about the three dimensional anatomy of the teeth especially those with an abnormality is necessary for a successful treatment.Keywords: Apical Periodontitis; Dens Invagination; Dens Invaginatus; Dens in Dente; Invaginated Teeth; Lateral Incisor; Periapical Lesio

Endodontic Treatment of a Tooth with Traumatic Fracture of Root Middle Third

Root fracture occurs in 0.5 to 7% of all dental injuries. Subsequent to this injury, the coronal segment is displaced, while the apical segment is rarely displaced. Emergency treatment involves repositioning of the coronal segment close to the radicular segment as much as possible to enhance the chance of pulp revascularization. If pulp necrosis occurs, the infective products cause an inflammatory response and radiolucency is seen at the fracture line. In the present case, the patient had two maxillary central incisors with horizontal middle third root fractures due to a traumatic accident four years earlier. The right central incisor showed an endodontic abscess due to pulp infection in the coronal segment. The coronal fragment was treated. In this case study all signs and symptoms resolved after treatment and three year follow-up showed a successful treatment outcome. The left central incisor had a vital pulp according to vitality tests, so “observation only” strategy was considered for this tooth.Keywords: Dental Pulp; Endodontic; Mineral Trioxide Aggregate; Tooth Fracture; Traum

Spontaneously Healed Horizontal Root Fracture: A Case Report

Objectives: Root fracture occurs less frequently in comparison with other traumatic dental injuries, and accounts for about 0.5%-7% of all dental injuries in permanent dentition. Complications associated with root fracture include pulp necrosis, root resorption, and pulp canal obliteration. Maintaining tooth vitality is the mainstay of treatment of horizontal root fracture in permanent teeth. Case Presentation: In this study, a clinical case of horizontal root fractures in the middle third of maxillary right and left central incisors (teeth #11 and #21) of an 8-year-old girl is reported. The patient was followed-up for 3 years. The treatment plan was watchful waiting and after 3 years, the vitality tests were still positive, and no pathology was detected on control radiographs. Conclusion: Careful clinical examination, accurate diagnosis, and regular radiographic follow-ups are necessary for efficient treatment and successful outcome of teeth with horizontal root fractures

The Effect of Root Coating with Titanium on Prevention of Root Resorption in Avulsed Teeth; An Animal Study

Introduction: Tooth avulsion is a real dental emergency. If immediate replantation is not performed, the avulsed tooth may be lost due to inflammatory or replacement resorption. This animal study aimed to evaluate the bone response to the titanium coating of the root surface as an artificial barrier, and prevention of resorption of avulsed teeth. Methods and Materials: This experimental study was conducted on four male dogs. The dogs were randomly divided into two groups for assessment at two and eight weeks. Four teeth were extracted in each animal. The root surfaces of the test group were coated with a titanium layer using the Electron Beam Deposition system. After 24 h, replantation of the teeth was performed. Two animals were sacrificed after two weeks and the remaining dogs were killed after eight weeks. The presence of inflammation, inflammatory resorption, replacement resorption, periodontal regeneration, periapical granuloma and ankylosis were evaluated through histological analyses. Results: Inflammatory root resorption was not present in any tooth except one tooth in the coated group after eight weeks. Replacement resorption was noted just in three of the non-coated teeth after two weeks and two teeth after eight weeks. The McNemar's test revealed that the frequency of replacement resorption in the non-coated group was significantly higher than the coated group (P=0.031). Conclusion: Based on the results of this study, it seems that coating the root surfaces of avulsed teeth with titanium may control the replacement root resorption.Keywords: Avulsion; Root Resorption; Titanium Coatin

Investigating the Relationship between Transactions with Affiliates and Fraudulent Reporting by Explaining the Moderating Role of Corporate Governance Companies Listed in Tehran Stock Exchange

Transactions with related parties have become a common way for fraudulent reporting due to the hiddenness and simplicity of manipulation, and the traditional methods of quantitative analysis have failed to discover the complex relationships of these transactions. Therefore, the detection of fraudulent reporting has attracted the attention of researchers and legislators. This research seeks to examine and test the relationship between transactions with related parties and fraudulent reporting by explaining the role of corporate governance moderation in companies listed on the Tehran Stock Exchange. The statistical population of this research includes 146 companies admitted to the Tehran Stock Exchange during a period of 9 years from 2012 to 2021. Multiple linear regression method has been used to test the research hypotheses. The results of the research showed that there is a positive and significant relationship between transactions with related parties and fraudulent reporting. In fact, the level of fraudulent reporting is higher in companies with related party transactions and fraudulent reporting. Also, the research results showed that there is a negative and significant relationship between corporate governance and fraudulent reporting. In other words, in companies where corporate governance is observed, the level of fraudulent reporting is lower. Examining the effect of corporate governance indicators on fraudulent reporting using unusual transactions with related parties shows that the independence of the board of directors and institutional shareholders has no significant effect on the relationship between transactions with related parties and fraudulent reporting, but the type of auditor has a direct and significant effect on the relationship between transactions with related parties and fraudulent reporting. Therefore, internal and external auditors, regulatory bodies, board of directors, and other professionals should identify this type of fraud and emphasize the importance of prevention approaches to reduce the possibility of committing corporate fraud. Regulators should also pay more attention to loan-based related party transactions and the total number of related party transactions

Synthesis and biological evaluation of novel tetranuclear cyclopalladated complex bearing thiosemicarbazone scaffold ligand: Interactions with double-strand DNA, coronavirus, and molecular modeling studies

International audienceThreading intercalators are a novel class of materials that carry two substituents along the diagonal positions of an aromatic ring. When bound to DNA, these substituents project out in DNA grooves. Tetranuclear complexes appear to be promising threading intercalators for developing therapeutics against cancer and viral infections that require high nucleic acid binding affinity. The objective of this work was to prepare the thiosemicarbazone scaffold ligand [4-ClC6H4CHN=NC(S)NHPh] and tetranuclear cyclopalladated complex [Pd(4-ClC6H4CHN=NC(S)NHPh)4] and to characterize the compounds by elemental analysis, 1D and 2D NMR, HRMS, and IR spectroscopy. The calf thymus DNA (CT-DNA) binding properties of the compounds were investigated in vitro under simulated physiological conditions using UV-vis spectroscopy, emission spectral titration, methylene blue competitive binding, circular dichroism, DNA thermal denaturation, DNA binding, and coronavirus interactions using molecular simulation. The compounds showed cytotoxic effect against both human breast (MCF-7) and colorectal (HCT116) cancer cells in a dose-dependent manner. We demonstrated that the compounds are promising for DNA threading intercalation binders with large DNA binding constants on the order of 107 M1 magnitude

Reduction of toxic organic dyes in aqueous media using N-heterocyclic copper(II) complex immobilized on the beta-cyclodextrin-modified Fe3O4 nanoparticles as a magnetically recyclable catalyst

This study was undertaken to design a stable easy-recoverable nanoadsorbent (Fe3O4@CM-β-CDP@Tet-Cu(II)) hybrid with rich catalytic sites via wet-chemical method for the catalytic reduction of toxic dyes in wastewater. β-cyclodextrin (β-CD) with a hydrophilic character outside and hydrophobic inside cavity play an important role in catalytic reduction process by interacting with organic molecules and also prepared more sites for further surface modifications. Several characterization techniques including FT-IR, TGA analysis, FE-SEM/EDX, TEM, X-Ray diffraction patterns (XRD) measurements were employed to investigate the structural properties of the synthesized material. The catalytic ability of the obtained material was examined in the presence of different dyes including p-nitrophenol, Eosin Y, Rhodamine B, Congo red, and Methyl orange by UV–Vis spectroscopy as a simple and available method. Moreover, the parameters which effect on reduction process, such as dye and reducing agent (NaBH4) concentrations, mass of adsorbent and time were optimized at room temperature. The obtained data demonstrate the considerable catalytic ability of Fe3O4@CM-β-CDP@Tet-Cu (II) besides a remarkable reduction rate and high yield over a short reaction time, in particular for Methyl orange dye. Recycling experiments revealed that Fe3O4@CM-β-CDP@Tet-Cu (II) has an excellent stability wherein the catalyst was recycled five times with a slight decrease in the reduction ability without any remarkable change in morphological properties which confirm by FE-SEM analysis. The high catalytic activity, the magnetic recoverability, along with the excellent stability of Fe3O4@CM-β-CDP@Tet-Cu (II) make it a potential candidate for the reduction of multiple dyes in real wastewater samples