Micro-Computed Tomographic Assessment of Microcrack Formation before and after Instrumentation of Curved Root Canals with Neoniti Rotary Files.

The aim of this study was to assess the microcrack formation of moderately and severely curved root canals following instrumentation with Neoniti rotary files using micro-computed tomography. This in vitro study evaluated 18 extracted sound mandibular molars with two separate mesial canals and foramina in two groups (n = 9) with 5-20° (moderate) and 20-40° (severe) root canal curvature. The number of microcracks in the root canal walls was counted at baseline by micro-CT. Subsequently, the root canals were instrumented with 0.20/0.06 v Neoniti files as single files with a torque of 1.5 Ncm and a speed of 400 rpm. The number of microcracks was counted again postoperatively on micro-CT images using Amira software. Statistical analysis was performed using the Shapiro-Wilk test, Levene's test and repeated-measures ANOVA (α = 0.05). The mean number of microcracks significantly increased postoperatively in both the moderately curved (11.59 ± 9.74 vs. 8.2 ± 7.4; p = 0.001) and the severely curved (13.23 ± 5.64 vs. 7.20 ± 5.94; p < 0.001) groups. However, the differences between the two groups were not significant (p = 0.668). Based on the results obtained, it can be stated that the instrumentation of moderately and severely curved root canals with Neoniti rotary files increases the number of microcracks. However, the higher degree of curvature does not necessarily translate to a higher number of microcracks after root canal instrumentation with this specific rotary system and methodological procedures

The Role of Mindfulness and its Dimensions in Predicting of Students’ Psychological Well-being

Background: Well-being is the biggest and most important goal of human being life that affects a person's health more than anything else does. This study aimed to investigate the role of mindfulness and its dimensions in students' psychological well-being. Methods: The research method was correlation and the statistical population included all students of Kharazmi University. The sample consisted of 240 students (126 females and 114 males) who were selected by the convenience sampling method. The research instruments were the Five Facet Mindfulness Questionnaire (FFMQ) (Bauer et al. 2006) and Ryff's scale of the Psychological Well-Being (Ryff, 1980). Data analysis was performed using independent groups of t-test, Pearson correlation coefficient, and stepwise regression. Results: The obtained results showed that there is no significant difference between male and female students in the variables of mindfulness and psychological well-being. There is a positive and significant correlation between psychological well-being and the overall score of mindfulness as well as the dimensions of observing, describing, acting with awareness, and non-reactive. Conclusions: The variables of acting with awareness and describing mindfulness dimensions were able to explain about 24% of the variance of psychological well-being in two steps. Keywords: Mindfulness, Psychological well-being, Student

Assessing sex differential in COVID-19 mortality rate by age and polymerase chain reaction test results: an Iranian multi-center study

Background The aim of this study is to evaluate the sex differential effect in the COVID-19 mortality by different age groups and polymerase chain reaction (PCR) test results. Research design In a multicenter cross-sectional study from 55 hospitals in Tehran, Iran, patients were categorized as positive, negative, and suspected cases. Results A total of 25,481 cases (14,791 males) were included in the study with a mortality rate of 12.0%. The mortality rates in positive, negative, and suspected cases were 20.55%, 9.97%, and 7.31%, respectively. Using a Cox regression model, sex had a significant effect on the hazard of death due to COVID-19 in adult and senior male patients having positive and suspected PCR test results. However, sex was not found as significant factor for mortality in patients with a negative PCR test in different age groups. Conclusions Regardless of other risk factors, we found that the effect of sex on COVID-19 mortality varied significantly in different age groups. Therefore, appropriate strategies should be designed to protect adult and senior males from this deadly infectious disease. Furthermore, owing to the considerable death rate of COVID-19 patients with negative test results, new policies should be launched to increase the accuracy of diagnosis tests

Comparison of MTA, CEM Cement, and Biodentine as Coronal Plug during Internal Bleaching: An In Vitro Study

Background. Internal bleaching is a choice of treatment in discolored endodontically treated teeth. Cervical root resorption is one of the important complications of this treatment. A suggested procedure to prevent this type of resorption is using a coronal barrier under the bleaching materials. The aim of the study was to compare the microleakage of mineral trioxide aggregate (MTA), calcium-enriched mixture (CEM) cement, and Biodentine. Materials and Methods. In this in vitro study, a total of 60 single canal incisors were included. They were randomly divided into three experimental groups (n = 16), one positive control group (n = 6), and one negative control group (n = 6). Coronal portion of the canals in the experimental groups was sealed with 3 mm of MTA, CEM cement, or Biodentine as a coronal barrier. After 3 days, specimens were bleached. A fresh Enterococcus faecalis suspension was added to the samples. The culture tubes were observed for 45 days, and the daily turbidity was recorded. Statistical analysis was accomplished by the Kaplan–Meier test and SPSS 22. Results. All positive samples showed turbidity, whereas none of the negative samples allowed bacterial leakage. Results showed no significant difference between MTA, CEM cement, and Biodentine groups. (P value = 0.304, 0.695, and 0.217). The bacterial microleakage for the two groups also did not show significant differences. Conclusions. CEM cement and Biodentine showed promising results as coronal plug, and clinical studies are needed to test these materials with MTA for avoiding microleakage in internal bleaching treatment

Association of Epstein-Barr virus with invasive breast carcinoma and its impact on well-known clinicopathologic parameters in Iranian women

Background: The association between Epstein-Barr virus (EBV) and breast carcinoma in Iranian women is uncertain. We examined EBV latent membrane protein-1 (LMP-1) antigen expression in breast carcinoma and its relationship with clinicopathologic parameters among a population of Iranian patients. Materials and Methods: This study was performed on formalin fixed and paraffin embedded tissue specimens with a diagnosis of invasive breast carcinoma archived at one university hospital in Isfahan city, Iran. We used immunohistochemistry to detect LMP-1 of EBV in carcinoma and its adjacent normal tissue. The frequency of LMP-1 expression in breast carcinoma and its relationship with age, tumor size, tumor type, tumor grade and lymph node status were then determined. Results: A total of 80 cases were evaluated including 77 (96.3%) ductal, 1 (1.3%) lobular, 1 (1.3%) medullary and 1 (1.3%) mucinous carcinoma. LMP-1 expression was seen in 6 cases (7.5%) of breast carcinoma whereas normal breast tissue adjacent to carcinoma was negative for LMP-1 in all of the cases. A statistically significant association was seen between EBV and invasive breast carcinoma (P = 0.03). No significant relationship was observed between LMP-1 expression on one hand and age, tumor size, tumor type, tumor grade and lymph node status on the other. Conclusion: EBV may play an etiological role in some of the cases of breast carcinoma in Iranian women. EBV expression does not seem to have a significant impact on the major clinicopathologic prognostic determinants of breast carcinoma

Comparative Evaluation of Apically Extruded Debris During Root Canal Preparation Using Three Different File Systems Applied Under 2.5% Sodium Hypochlorite or 2% CHX Irrigation

The chemomechanical cleaning of the root canal system is performed using manual and rotary files. This study aimed to compare the effect of ProTaper, Reciproc and HyFlex rotary files considering 2.5% sodium hypochlorite and 2% chlorhexidine (CHX) as irrigating solutions on apical extrusion of intracanal debris. Single-canal mandibular premolars (N=165) were evaluated. The teeth were divided into 6 experimental groups (N=25) for root canal instrumentation using 3 file systems, (Reciproc, HyFlex and ProTaper) and two irrigation solutions, namely 2.5% sodium hypochlorite or 2% CHX. Fifteen teeth were also assigned into three control groups (n=5) with saline as irrigation solution. Eppendorf tubes were weighed and the teeth were placed inside. The canals were instrumented and the tubes weighed to determine the dry weight of extruded debris. Data were analyzed using one-way ANOVA and Bonferroni test (α=0.05). The mean amount of extruded debris using the sodium hypochlorite solution was significantly higher than other irrigating solutions (p⟨0.001). The mean amount of extruded debris using the Reciproc file system was significantly higher compared to ProTaper and HyFlex (p⟨0.001). The use of the sodium hypochlorite solution, single-file systems and reciprocal movement are associated with higher debris extrusion and might be associated with higher risk of postoperative pain

Evaluation of the predictive value of fetal Doppler ultrasound for neonatal outcome from the 36th week of pregnancy

Background: Early prediction of adverse neonatal outcome would be possible by Doppler impedance indices of middle cerebral artery (MCA), umbilical artery (UmA), and descending aortal artery (AO) that result in decrease neonatal morbidity and mortality rate. The aim of the present study was a determination of optimal value for the ratio of MCA to descending aorta blood flow (MCA/AO) impedance indices and its comparison with the ratio of MCA to UmA (MCA/UmA) impedance indices and their relationship with neonatal outcome. Materials and Methods: This was a prospective cohort study on 212 pregnant women with gestational age 36 weeks or more, in three hospitals in Tehran, from April 2012 to April 2013. We investigated AO, MCA, and UmA impedance indices Doppler ultrasound every 2 weeks till delivery. The mother was monitored for adverse pregnancy outcome (hypertension [HTN], fetal growth retardation, and other maternal complications) then infant birth weight, cord blood of pH, and Neonatal Intensive Care Unit (NICU) admission during the first 24 h after delivery were assessed. Finally, we investigated relationships between Doppler indices and neonatal outcomes include neonatal body weight (NBW), cord blood of pH, and NICU admission. Results: MCA/AO resistance index (RI) and MCA/AO pulsatile index (PI) showed an area under the receiver operating characteristics curve (area under the curve) of 0.905 (95% confidence interval (CI): 0.850, 0.959) and 0.818 (95% CI: 0.679, 0.956), respectively. The cutoff values for pH (≥7.2 vs. <7.2) based on MCA/AO RI and MCA/AO PI indices were 0.951 (sensitivity, 80% and specificity, 86%) and 0.853 (sensitivity, 91% and specificity, 83%), respectively. The cutoff value for NBW (≥2500 vs. <2500 g) based on MCA/UmA PI index was 1.467 (sensitivity, 73% and specificity, 63%). The cutoff value of NICU admission of child based on MCA/AO PI index was 1.114 (sensitivity, 73% and specificity, 54%). Conclusion: In the end of third-trimester pregnancies with the assessment of MCA and AO artery Doppler ultrasonography, it is possible to prevent many cases of neonatal acidosis caused by prenatal asphyxia as well as inappropriate interventions which are applied on mother. If MCA/AO PI was <0.85, the fetus needs to be evaluated further because it is at risk for acidosis

Micro-Computed Tomographic Assessment of Microcrack Formation before and after Instrumentation of Curved Root Canals with Neoniti Rotary Files

The aim of this study was to assess the microcrack formation of moderately and severely curved root canals following instrumentation with Neoniti rotary files using micro-computed tomography. This in vitro study evaluated 18 extracted sound mandibular molars with two separate mesial canals and foramina in two groups (n = 9) with 5-20° (moderate) and 20-40° (severe) root canal curvature. The number of microcracks in the root canal walls was counted at baseline by micro-CT. Subsequently, the root canals were instrumented with 0.20/0.06 v Neoniti files as single files with a torque of 1.5 Ncm and a speed of 400 rpm. The number of microcracks was counted again postoperatively on micro-CT images using Amira software. Statistical analysis was performed using the Shapiro-Wilk test, Levene's test and repeated-measures ANOVA (α = 0.05). The mean number of microcracks significantly increased postoperatively in both the moderately curved (11.59 ± 9.74 vs. 8.2 ± 7.4; p = 0.001) and the severely curved (13.23 ± 5.64 vs. 7.20 ± 5.94; p &lt; 0.001) groups. However, the differences between the two groups were not significant (p = 0.668). Based on the results obtained, it can be stated that the instrumentation of moderately and severely curved root canals with Neoniti rotary files increases the number of microcracks. However, the higher degree of curvature does not necessarily translate to a higher number of microcracks after root canal instrumentation with this specific rotary system and methodological procedures

Continuing Pregnancy Despite Prenatal Diagnosis of a Life-Limiting Fetal Anomaly and Need for Perinatal Palliative Care Service Package: A Qualitative Study from Iran

Background: Prenatal diagnosis of fetal anomalies leads to parental psychological stress and decision-making challenges to continue or terminate pregnancy. Continuing pregnancy despite fetal anomaly can cause confusion, anxiety and depression in parents, so it seems necessary to be aware of their needs and appropriately respond to them. This study was conducted to exploring experiences about Continuation Pregnancy despite fetal anomaly in the socio-cultural context of Iran. Methods: Qualitative exploratory descriptive study, 35 participants including 15 pregnant women with Life-Limiting fetal anomaly diagnosis, 5 family members and 15 perinatal care providers were selected purposefully. Data were gathered by individual interview and were written, important phrases were coded, by grouping same codes, main and sub categories were extracted. Results: In this study, 4 main categories, each with a number of subcategories were extracted. The main categories included: ``mental health counseling, support parents to accept and cope with event, ethical consideration during end-of-life care of baby, providing perinatal palliative care)''. Conclusion: The results showed that parents who forcibly or voluntarily continue pregnancy after a wearing of fetal anomalies, have extensive care needs during pregnancy and after birth that are not sufficiently met. Therefore, it seems that a comprehensive service package of perinatal palliative care appropriate for Iran socio- cultural context is necessary

Is preterm placental calcification related to adverse maternal and foetal outcome?

This prospective cohort study aimed to evaluate the role of premature placental calcification in adverse pregnancy outcomes and identify its associated potential risk factors. We consecutively enrolled 293 women who presented to three academic medical centres from September 2011 to March 2013. Participants underwent transabdominal sonographies between 28–36 weeks of gestation in an attempt to determine placental maturity. We compared maternal and foetal outcomes between two groups of women, those with grade III placenta (n = 69) and those without grade III placenta (n = 224). Passive smoking was the only predictor of early placental calcification. There were more abnormal Doppler, low birth weight (LBW) and caesarean section (CS) deliveries observed in the preterm calcification group. No definite relationship existed between maternal hypertension (HTN), diabetes and other medical diseases with placental calcification. In conclusion, umbilical artery (UA) resistance index (RI) and absent or reversed end-diastolic velocity (AREDV) were observed more often in preterm placental calcification. Serious antepartum follow-up should be advised for these mothers.Impact Statement  • Placental calcification is a physiological phenomenon but normally, a grade III placenta is not frequently found until 36 weeks of gestation (so is called preterm placental calcification – PPC). There is currently a lack of consistent evidence on the clinical significance of PPC and pregnancy outcome. The present study was designed to evaluate the role of PPC in adverse pregnancy outcomes.  • In our study, although none of the pregnant women were smokers, we found that passive smoking was the only predictor of PPC. Abnormal umbilical artery Doppler waveforms considerably and absent end diastolic velocity pattern significantly were observed more often in the PPC group.  • We observed that PPC can be a landmark for high-risk pregnancy and an alarm sign for placental dysfunction. So, close antepartum follow up should be advised for these mothers. Regular and frequent foetal wellbeing tests should be done to prevent pregnancy complications. Certainly larger and more extensive study can provide more valid results