Accessing Calcified Teeth Using Dynamic Guidance System

Introduction: one of the most common challenging scenarios that a clinician faces on a regular basis is the treatment of a calcified tooth. Using CBCT to identify canals is becoming the standard of care and a tremendous help to clinicians. More recently, Dynamic guidance is becoming a popular among clinicians for dealing with challenging cases such as calcification. Objective: The aim of this study was to evaluate the accuracy of endodontic access of calcified anterior mandibular and maxillary teeth using dynamic guidance. Material and Method: 42 extracted calcified human mandibular and maxillary anterior teeth were selected. Rubber model former mold was used to mount the extracted teeth in the proper position to mimic the human jaw, and CBCT images were captured. Preoperative CBCT scans were transferred to the Dynamic Guidance system software for planning of endodontic access. To simulate a clinical scenario, the dentoforms were mounted to a manikin and placed on an operatory chair. Post-removal burs were used to gain access to the canal after calibration was completed. Once the proper depth was reached, the software prompted the operator to stop. The procedure was terminated at this point, regardless of the success of the operator to locate the canals or not. After completion, the access was evaluated by the passive placement of a #6 C file in the canal to ensure access/patency of the canal. A post-operative CBCT with and without the file in the access was taken. The teeth were then decoronated at the cementoenamel junction to remove any obstruction that would potentially deflect the file, and a file was placed in the canal and a CBCT was taken with the file. All images were assessed for access deviation and accuracy, followed by comparative statistics. Results: Of the 32 included in this study, 28 (87.5%) canals were successfully located. The angular deviation was calculated after superimposing the pre-op CBCT over the post-op CBCT by measuring the angle between the file and the natural path of the physical canal. The average angular deviation was 4.69 degrees, the average platform buccolingual deviation was 0.38 mm, the average platform mesiodistal direction was 0.23 mm, the average of non-depth deviation (deviation in any direction other than apico-coronally) was 0.99 mm, and the average of apical non-depth deviation at the apical extent of the file trajectory was 0.70 mm Conclusion: Calcified canals were located by an inexperienced operator in 87.5% of the time with an angular deviation of 4.69 degrees which confirms that dynamic guide syste

In vitro lethal effects of various extracts of Nigella sativa seed on hydatid cyst protoscoleces

Objective(s): There are several scolicidal agents for inactivation of hydatid cyst protoscolices during surgery, but most of them are associated with adverse side effects such as sclerosing cholangitis and liver necrosis. The present study was aimed to evaluate scolicidal effects of various extracts of Nigella sativa seeds against protoscoleces of hydatid cyst in an in vitro model. Materials and Methods: Protoscoleces were aseptically aspirated from naturally infected livers of sheep and goats. Various concentrations of the different extracts of N. sativa (5 to 50 mg/ml) were used for 5 to 60 min. Viability of protoscoleces was confirmed by 0.1% eosin staining. Results: The findings exhibited that methanolic extract at the concentration of 50 mg/ml after 10 min of incubation, and aqueous extract at the concentration of 50 mg/ml after 30 min of incubation can kill 100% of protoscoleces. In addition, all of experiments revealed dose-dependent and also time-dependent scolicidal effect of various extracts of N. sativa on the protoscoleces of hydatid cyst. Conclusion: The results of the present study demonstrated that N. sativa may be a natural source for the production of new scolicidal agent for use in hydatid cyst surgery. However, further studies will be required to evaluate scolicidal effects of N. sativa in the in vivo model

E-learning in Medical Sciences: A survey of Students\' Views on e-learning

Introduction: Parallel with the development of information and communication technology, a new approach to learning has emerged, namely. Administering e-learning at Isfahan University of Medical Sciences as one of the objectives of the strategic plan of the educational assistantship requires extensive study for the presence of students in the e-learning contexts. This study endeavored to examine the readiness of students at Isfahan University of Medical Sciences in relation to e-learning. Methods: This descriptive cross-sectional study was conducted in the academic year 2018; 412 students were selected from the 6079 students of Isfahan University of Medical Sciences using Cochran formula. Data was gathered through a researcher-made questionnaire as available sampling. The validity of the questionnaire was confirmed by the professors of the Department of Health Information Management and Technology. The reliability of the questionnaire was computed through Cronbach's alpha coefficient r= 0.93. To analyze the data, descriptive and inferential statistics (Pearson correlation) were used. Results: Results revealed that most of the e-learning factors had significant differences among the different levels (P≤0.05). Students' experiences of participation in e-learning were important factor; however, time management was the least important factor. Information and communication technology skills factors had the highest positive correlation with learning ability (r=0.623), learning habits with learning ability (r=0.654), and motivation with e-learning usefulness (r=0.660). Conclusion: This study can be used as a guideline for Isfahan University of Medical Sciences to invest in time management and incentives for low-level e-learning before implementing the courses electronically and to address the barriers and administer e-learning

Univariate analysis of factors associated with the prevalence of HIV, HCV, HBV and latent TB on homeless people in Tehran.

<p><b>*Median of the variable is used for analysis.</b></p><p><b>**A purified and potent form of heroin (not to be mistaken with crack cocaine).</b></p

Baseline characteristics of newly diagnosed HIV-1 infected patients in Iran.

1<p>Information on gender, age, and city of residence were obtained from all 50 cases who completed the questionnaire.</p>2<p>Information on marital status and transmission route were obtained from 35 cases who completed questionnaires.</p>3<p>Infection with hepatitis C virus and hepatitis B virus were tested in 30 and 28 cases, respectively.</p

Phylogenetic trees of sequenced Iranian samples.

<p>(A) protease, (B) reverse transcriptase, (C) integrase, (D) gag, and (E) env. Trees were constructed using neighbour joining method with 1000 replicates. Two sequences each of 6 HIV-1 subtypes retrieved from the GenBank are included as references. Open circles (○) indicate the reference sequence of CRF35_AD, open squares (□) indicate subtype A1, open triangles (▵) indicate A2, open diamonds (◊) indicate subtype D, closed circles (•) indicate subtype B, and closed squares (▪) indicate CRF01_AE. Bootstrap values over 70% are shown.</p

Prevalence of drug resistance-associated mutations among 47 sequenced samples.

<p>IAS-USA, the international Antiviral society-USA; NRTI, nucleoside reverse transcriptase inhibitor; PI, protease inhibitor; SDRMs, surveillance drug-resistant mutations.</p