Comparative Study of Different Novel Nickel-Titanium Rotary Systems for Root Canal Preparation in Severely Curved Root Canals

Introduction

We compared the effects of 6 different rotary systems on transportation, canal curvature, centering ratio, surface area, and volumetric changes of curved mesial root canals of mandibular molar via cone-beam computed tomographic (CBCT) imaging.

Methods

Mesiobuccal root canals of 120 mandibular first molars with an angle of curvature ranging from 20°–40° were divided into 6 groups of 20 canals. Based on CBCT images taken before instrumentation, the groups were balanced with respect to the angle and radius of canal curvature. Root canals were shaped with the following systems with an apical size of 25: OneShape (OS) (MicroMega, Besancon, France), ProTaper Universal (PU) F2 (Dentsply Maillefer, Ballaigues, Switzerland), ProTaper Next X2 (Dentsply Maillefer), Reciproc (R) R25 (VDW, Munich, Germany), Twisted File Adaptive (TFA) SM2 (SybronEndo, Orange, CA), and WaveOne primary (Dentsply Tulsa Dental Specialties, Tulsa, OK). After root canal preparation, changes were assessed with CBCT imaging. The significance level was set at P = .05.

Results

The R system removed a significantly higher amount of dentin than the OS, PU, and TFA systems (P < .05). There was no significant difference among the 6 groups in transportation, canal curvature, changes of surface area, and centering ratio after instrumentation.

Conclusions

The 6 different file systems straightened root canal curvature similarly and produced similar canal transportation in the preparation of mesial canals of mandibular molars. R instrumentation exhibited superior performance compared with the OS, TFA, and PU systems with respect to volumetric change.     

Achieving the desired colour in discoloured teeth,using leucite-based cad-cam laminate Systems

Objectives

To evaluate the cumulative effect of the abutment tooth and resin cement colour on the resultant optical properties of porcelain laminate veneers (PLVs) fabricated with leucite-based CAD/CAM blocks with different shades and thicknesses.

Methods

A total of 224 ceramic specimens were prepared from the IPS Empress CAD with four different shades of HT-A1, LT-A1, MT-A1 and Bl-1. Resin composite discs were prepared with shade A3.5. For the cementation, 4 different shades of light-cure resin cements were chosen. L*, a*, and b* values, as well as the chroma (C) and hue (h) values of each cemented ceramic and the A1 shade table, were recorded.

Results

L*, C_ab* and h_ab* values of the cemented ceramics were influenced by ceramic shade, ceramic thickness, cement shade, and interaction terms of the three variables. There were significant differences between the 1-mm-thick ceramic veneers that exhibited higher L* and lower C_ab* values compared with veneers that were 0.5 mm in thickness. Using the Tr shade cement resulted in lower L* and higher C_ab* values for all thicknesses and ceramic shades, whereas the WO shade cement resulted in higher values.

Conclusions

The selected colour of a laminate restoration is significantly affected by the ceramic shade, ceramic thickness and resin cement shade. Using the WO shade resin cement seems to be more effective in masking the discoloured abutment tooth. Clinicians should also select the translucency level of the ceramic block with the shade when a leucite-based CAD/CAM system is chosen to treat a discoloured tooth.     

Knowledge,Practices and Use of Contact Lenses Among University Students in Turkey

AimThis study was conducted to determine the prevalence of contact lens (CL) use among university students, their awareness on CL, and CL users'' practices for the cleaning and care of CLs.MethodsThe data of this cross-sectional study were collected between April 2019 and July 2019. The sample consisted of university students who volunteered to participate in the study. The data obtained from the study were evaluated by Statistical Package for the Social Science (SPSS) 22.0 package program in computer environment.Results929 students participated in the study and the average age of them was 21.99±1.85 years (Min. 18 – Max. 24), and it was determined that 36.6% (n=340) of the participants were male, 10.2% (n=95) of the total were using CL, 91.6% (n=87) of them used CL due to visual impairment. When students'' levels of knowledge about the hygiene and care in CL use were examined 85.4% (n=82) washed their hands before wearing/removing CL, 85.3% (n=81) cleaned the lens container and filled it with new solution when the solution in the container was reduced, 18.5% (n=17) continued wearing CL while sleeping, 6.5% (n=6) washed CL with tap water, and 28.3% (n=26) of them stated that they swam in the sea with CL. It was determined that the prevalence of CL use was higher (p= .045) among smoking students.ConclusionHealth professionals are important in the trainings to be given to increase the students'' knowledge of hygiene and care regarding the use of CL. More studies are needed on the effect of smoking status on CL use.     

Recommendations for Hepatitis B Immunoglobulin and Antiviral Prophylaxis Against Hepatitis B Recurrence After Liver Transplantation

The combination of hepatitis B immunoglobulin and potent nucleos(t)ide analogs after liver transplantation is considered as the standard of care for prophylaxis against hepatitis B virus recurrence. However, the recommended doses, route of administration, and duration of HBIG administration remain unclear. Moreover, hepatitis B immunoglobulin-free prophylaxis with potent nucleos(t)ide analogs has shown promising disease outcomes in preventing hepatitis B virus recurrence. The current recommendations, produced by the Turkish Association for the Study of the Liver, Acute Liver Failure and Liver Transplantation Special Interest Group, suggest a reduced need for hepatitis B immunoglobulin administration with effective long-term suppression of hepatitis B virus replication using potent nucleos(t)ide analogs after liver transplantation.     

The neutralization effect of montelukast on SARS-CoV-2 is shown by multiscale in silico simulations and combined in vitro studies

Small molecule inhibitors have previously been investigated in different studies as possible therapeutics in the treatment of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). In the current drug repurposing study, we identified the leukotriene (D4) receptor antagonist montelukast as a novel agent that simultaneously targets two important drug targets of SARS-CoV-2. We initially demonstrated the dual inhibition profile of montelukast through multiscale molecular modeling studies. Next, we characterized its effect on both targets by different in vitro experiments including the enzyme (main protease) inhibition-based assay, surface plasmon resonance (SPR) spectroscopy, pseudovirus neutralization on HEK293T/hACE2+TMPRSS2, and virus neutralization assay using xCELLigence MP real-time cell analyzer. Our integrated in silico and in vitro results confirmed the dual potential effect of montelukast both on the main protease enzyme inhibition and virus entry into the host cell (spike/ACE2). The virus neutralization assay results showed that SARS-CoV-2 virus activity was delayed with montelukast for 20 h on the infected cells. The rapid use of new small molecules in the pandemic is very important today. Montelukast, whose pharmacokinetic and pharmacodynamic properties are very well characterized and has been widely used in the treatment of asthma since 1998, should urgently be completed in clinical phase studies and, if its effect is proved in clinical phase studies, it should be used against coronavirus disease 2019 (COVID-19).     

HMGB‐1, TLR4, IL‐1R1, TNF‐α, and IL‐1β: novel epilepsy markers?

Aim: The purpose of this study was to compare HMGB‐1, TLR4, IL‐1β, IL‐1R1, and TNF‐α levels in patients with mild and severe epilepsy with those in a healthy control group. Methods: Children aged 4–17 years, diagnosed with epilepsy for at least three years and with no progressive neurological disease, metabolic disease or infection, were selected for the study. The severe epilepsy group consisted of 28 children with at least one episode a week despite receiving three or more antiepileptic drugs. The mild epilepsy group consisted of 29 children with no seizures in the previous year, receiving only one antiepileptic drug, while 27 healthy children were selected as the control group. HMGB‐1, TLR4, IL‐1R1, TNF‐α and IL‐1β levels were investigated in these three groups. The MRI findings and clinical characteristics of the patients in the epilepsy group were also compared with these markers. Results: HMGB‐1, TLR4, TNF‐α, and IL‐1β levels in the severe epilepsy group were higher than in the control group and the mild epilepsy group (p<0.05), and were higher in the mild epilepsy group than in the control group (p<0.05). IL‐1R1 was also higher in the severe epilepsy group than in the control group (p<0.05). Conclusion: In this first report to identity a possible correlation between HMGB‐1, TLR4, IL‐1β, IL‐1R1, and TNF‐α levels and severity of epilepsy, our data demonstrates that the serum level of these cytokines is higher in cases of drug‐refractory epilepsy.     

Complication and cost analysis of transbronchial lung cryobiopsy and awake video-assisted thoracic surgery in diagnosis of interstitial lung disease

Aim and introduction:Diagnosing of interstitial lung disease (ILD) is difficult and expensive. The standard diagnostical approaches to ILD are bronchoalveolar lavage, transbronchial lung biopsy, transbronchial lung cryobiopsy (TBLC) and surgical lung biopsy (SLB). SLB is gold standard for the confident diagnosis of ILD but because of the poor performance of the patients it’s use is limited. We conducted a retrospective study to point out that TBLC plays an important role in diagnosis of ILD and has fewer complications and lower cost than awake video-assisted thoracic surgery (AVATS).Material and methods:132 patients who underwent TBLC and AVATS with a pre-diagnosis of ILD in our hospital between 2015 and 2020 were evaluated retrospectively. Diagnosis rates, complications and costs were recorded.Results:There were no non-diagnostic materials in 44 patients in AVATS arm. Prolonged air leak was observed in 11(25.0%) of the patients, and six of them (13.6%) were discharged with Heimlich Valve (HV). Median length of stay in the hospital was 8 days, while average patient cost was $515.9 (415.2-2662.9) in the AVATS arm. Non-diagnostic material was obtained from 10 (11.3%) of 88 patients in TBLC arm. Six (6.8%) of them had pneumothorax, only one of them required a chest tube. No patient was discharged with HV (p=0.001). Median cost for each patient with a median hospital stay of 2.0 (1.0-21.0) (p<0.001) days was $171.9 (80.8-1493.3) (p<0.001).Discussion:Although TBLC is behind AVATS in terms of diagnostic accuracy, it may be an alternative diagnostic tool in the diagnosis of interstitial lung disease due to its acceptable safety profile and cost-effectiveness.     

Deficiency of adenosine deaminase 2; special focus on central nervous system imaging

Purpose

To increase the knowledge of central nervous system (CNS) imaging features in deficiency of adenosine deaminase 2 (DADA2) by examining magnetic resonance imaging (MRI) studies of a relatively large number of patients.