Success Rate and Time for Bypassing the Fractured Segments of Four NiTi Rotary Instruments

Introduction: The aim of this in vitro study was to compare the success rate and time required for bypassing the fractured segments of four different nickel-titanium (NiTi) rotary systems. Methods and Materials: This study was conducted on the mesiobuccal canals of 60 mandibular molars with fully-formed apices. Fifteen Flex Master, K3, RaCe and Hero Shaper instruments with 0.04 taper and tip size of #30 and 25 mm in length, were obtained. These instruments were notched at a point 3 mm from the tip of the instrument and were driven into the canals using a handpiece until the instruments fractured and became lodged therein. In the next step, an endodontist tried to bypass the fractured segment using K-files. The number of bypassed samples and the time required for bypassing of each sample were recorded. The Chi-square test was used to compare the bypassing rate among the experimental groups. One-way analysis of variance followed by Tukey’s post hoc test was conducted to compare the time taken for bypassing of the fractured fragments. Results: One instrument in Flex Master group and two broken segments in each of the K3 and Hero groups were not bypassed. All of the samples in RaCe group were bypassed. No significant difference was found among four tested groups regarding rate of bypassing (P=0.738). The time taken to bypass fragments in the Hero group was significantly more than in those of K3 (P=0.047) and RaCe (P=0.024). Conclusion: Under the limitations of this study, design features of rotary files can influence the time needed to bypass separated fragments.Keywords: Instrument Fracture; Instrument Separation; File Fracture; Fractured Instrument; NiTi Rotary File; Root Canal Treatmen

In Vitro Evaluation of Dynamic Viscosity, Surface Tension and Dentin Wettability of Silver Nanoparticles as an Irrigation Solution

Introduction: The aim of this study was to evaluate dynamic viscosity, surface tension and dentin wettability of a newly introduced imidazolium-based silver nanoparticle solution (Im AgNP) in comparison with three common root canal irrigants. Methods and Materials: The irrigants were Im AgNPs at 5.7×10-8 mol/L-1, 5.25% Sodium hypochlorite (NaOCl), 2% Chlorhexidine (CHX) and 17% Ethylenediaminetetraacetic acid (EDTA) and distilled water (control group). Dynamic viscosity was measured using rotational digital viscometer at 25, 37, 45 and 60°C. Surface tension was evaluated using dynamic contact angle analyzer at room temperature (25°C). Wettability was assessed by contact angle measurement for five groups of 10 dentin samples after each group was treated in each irrigant for 10 min. One-way ANOVA, and post hoc Tukey’s test were used for statistical analysis. Significance was set at P<0.05. Results: Dynamic viscosity of all irrigants decreased as the temperature increased. 17% EDTA was the most viscous solution in all examined temperatures (P<0.05). Viscosity of Im AgNP solution at 25, 37 and 45°C was significantly lower than that of 17% EDTA and 5.25% NaOCl (P<0.05). Im AgNPs exhibited a higher surface tension than other irrigants except distilled water. The wettability of dentin increased when it was in contact with 2% CHX and 5.25% NaOCl while Im AgNPs decreased the wettability of dentin surfaces (P<0.05). Conclusion: Im AgNP irrigant has the potential to reach apical portions of root canals due to its lower viscosity compared to the other tested irrigants. However, it may not bring better penetration inside dentinal tubules because of its higher surface tension. Furthermore, Im AgNPs can influence physiochemical properties of dentin by decreasing its surface wettability.Keywords: Irrigant; Silver Nano Particle; Surface Tension; Viscosity; Wettabilit

Effect of imidazolium based silver nanoparticle irrigant on root canal dentin roughness in comparison with three common irrigants

Introduction: The aim of this study is to evaluate the effect of a newly introduced nanosilver based irrigant on dentin roughness in comparison with three commonly used root canal irrigants.Material and methods: Irrigants tested were: NaOCl 5.25%, EDTA 17%, CHX 2% and newly introduced imidazolium-based silver nanoparticle (Im AgNP) irrigant at 5.8×10 -8 mol/L. Distilled water was used as control. Roots of 25 human anterior teeth were sectioned longitudinally to obtain 50 dentin samples. Roughness values were evaluated by Atomic Force Microscopy analysis on 5 groups of 10 samples after each group were treated in one of the tested irrigant solutions for 10 minutes.Results: Dentin roughness significantly increased from 95.82 nm (control) to 136.02 nm, 187.07 nm, 142.29 nm and 150.92 nm by NaOCl, CHX, Im AgNP irrigant and EDTA respectively. CHX demonstrated a significantly higher roughness value compared to the other irrigants tested while no significant differences were seen in NaOCl, Im AgNP irrigant and EDTA groups. (P>0.05)Conclusions: Im AgNP irrigant affect physicochemical property of dentin and raised its surface roughness, thus, this irrigant could impact bacterial and restorative material adhesion to root canal dentin walls.

Comparison between Alpha and Calendula for Healing of Third-Degree Burn in Rats: Burn healing in rat by Alpha and Calendula

In this study, we compared the effects of Calendula and Alpha ointment in the treatment of burn wounds and also compared its results with silver sulfadiazine (SSD). Seventy-five male Sprague-Dawley rats were divided into five groups, and similar burn ulcers were produced on anterior surface of thigh of rats. In the first group of rats no treatment was applied, base gel was applied topically to group II, in groups III-V, Alpha, SSD, and Calendula preparations were applied, respectively. Wound healing, contraction, and histopathological evaluation were evaluated at the end of 7, 14, and 21 days. Alpha ointment was equally effective as Calendula gel, and had better efficacy compared to SSD for all markers of wound healing at days of 7, 14, and 21.Alpha and Calendula preparations are less expensive drugs and significantly improve the quality of wound healing and scar formation and are more appropriate treatment choices than SSD. Therefore, we recommended them as alternative to SSD, especially in patients with low economical backgrounds or in those who show adverse reactions to SSD

Prevalence of plasma lipid abnormalities and associated risk factors among Iranian adults based on the findings from STEPs survey 2021

Abstract The study aimed to estimate the prevalence of lipid abnormalities in Iranian adults by demographic characterization, geographical distribution, and associated risk factors using national and sub-national representative samples of the STEPs 2021 survey in Iran. In this population-based household survey, a total of 18,119 individuals aged over 25 years provided blood samples for biochemical analysis. Dyslipidemia was defined by the presence of at least one of the lipid abnormalities of hypertriglyceridemia (≥ 150 mg/dL), hypercholesterolemia (≥ 200 mg/dL), high LDL-C (≥ 130 mg/dL), and low HDL-C (< 50 mg/dL in women, < 40 mg/dL in men), or self-reported use of lipid-lowering medications. Mixed dyslipidemia was characterized as the coexistence of high LDL-C with at least one of the hypertriglyceridemia and low HDL-C. The prevalence of each lipid abnormality was determined by each population strata, and the determinants of abnormal lipid levels were identified using a multiple logistic regression model. The prevalence was 39.7% for hypertriglyceridemia, 21.2% for hypercholesterolemia, 16.4% for high LDL-C, 68.4% for low HDL-C, and 81.0% for dyslipidemia. Hypercholesterolemia and low HDL-C were more prevalent in women, and hypertriglyceridemia was more prevalent in men. The prevalence of dyslipidemia was higher in women (OR = 1.8), obese (OR = 2.8) and overweight (OR = 2.3) persons, those residents in urban areas (OR = 1.1), those with inappropriate physical activity (OR = 1.2), patients with diabetes (OR = 2.7) and hypertension (OR = 1.9), and participants with a history (OR = 1.6) or familial history of CVDs (OR = 1.2). Mixed dyslipidemia prevalence was 13.6% in women and 11.4% in men (P < 0.05). The prevalence of lipid abnormalities was highly heterogeneous among provinces, and East Azarbaijan with 85.3% (81.5–89.1) and Golestan with 68.5% (64.8–72.2) had the highest and lowest prevalence of dyslipidemia, respectively. Although the prevalence of high cholesterol and LDL-C had a descending trend in the 2016–2021 period, the prevalence of dyslipidemia remained unchanged. There are modifiable risk factors associated with dyslipidemia that can be targeted by the primary healthcare system. To modify these risk factors and promote metabolic health in the country, action plans should come to action through a multi-sectoral and collaborative approach

The burden of metabolic risk factors in North Africa and the Middle East, 1990–2019: findings from the Global Burden of Disease StudyResearch in context

Summary: Background: The objective of this study is to investigate the trends of exposure and burden attributable to the four main metabolic risk factors, including high systolic blood pressure (SBP), high fasting plasma glucose (FPG), high body-mass index (BMI), and high low-density lipoproteins cholesterol (LDL) in North Africa and the Middle East from 1990 to 2019. Methods: The data were retrieved from Global Burden of Disease Study 2019. Summary exposure value (SEV) was used for risk factor exposure. Burden attributable to each risk factor was incorporated in the population attributable fraction to estimate the total attributable deaths and disability-adjusted life-years (DALYs). Findings: While age-standardized death rate (ASDR) attributable to high-LDL and high-SBP decreased by 26.5% (18.6–35.2) and 23.4% (15.9–31.5) over 1990–2019, respectively, high-BMI with 5.1% (−9.0–25.9) and high-FPG with 21.4% (7.0–37.4) change, grew in ASDR. Moreover, age-standardized DALY rate attributed to high-LDL and high-SBP declined by 30.2% (20.9–39.0) and 25.2% (16.8–33.9), respectively. The attributable age-standardized DALY rate of high-BMI with 8.3% (−6.5–28.8) and high-FPG with 27.0% (14.3–40.8) increase, had a growing trend. Age-standardized SEVs of high-FPG, high-BMI, high-SBP, and high-LDL increased by 92.4% (82.8–103.3), 76.0% (58.9–99.3), 10.4% (3.8–18.0), and 5.5% (4.3–7.1), respectively. Interpretation: The burden attributed to high-SBP and high-LDL decreased during the 1990–2019 period in the region, while the attributable burden of high-FPG and high-BMI increased. Alarmingly, exposure to all four risk factors increased in the past three decades. There has been significant heterogeneity among the countries in the region regarding the trends of exposure and attributable burden. Urgent action is required at the individual, community, and national levels in terms of introducing effective strategies for prevention and treatment that account for local and socioeconomic factors. Funding: Bill & Melinda Gates Foundation

Adolescent transport and unintentional injuries: a systematic analysis using the Global Burden of Disease Study 2019

Background Globally, transport and unintentional injuries persist as leading preventable causes of mortality and morbidity for adolescents. We sought to report comprehensive trends in injury-related mortality and morbidity for adolescents aged 10-24 years during the past three decades. Methods Using the Global Burden of Disease, Injuries, and Risk Factors 2019 Study, we analysed mortality and disability-adjusted life-years (DALYs) attributed to transport and unintentional injuries for adolescents in 204 countries. Burden is reported in absolute numbers and age-standardised rates per 100 000 population by sex, age group (10-14, 15-19, and 20-24 years), and sociodemographic index (SDI) with 95% uncertainty intervals (UIs). We report percentage changes in deaths and DALYs between 1990 and 2019. Findings In 2019, 369 061 deaths (of which 214337 [58%] were transport related) and 31.1 million DALYs (of which 16.2 million [52%] were transport related) among adolescents aged 10-24 years were caused by transport and unintentional injuries combined. If compared with other causes, transport and unintentional injuries combined accounted for 25% of deaths and 14% of DALYs in 2019, and showed little improvement from 1990 when such injuries accounted for 26% of adolescent deaths and 17% of adolescent DALYs. Throughout adolescence, transport and unintentional injury fatality rates increased by age group. The unintentional injury burden was higher among males than females for all injury types, except for injuries related to fire, heat, and hot substances, or to adverse effects of medical treatment. From 1990 to 2019, global mortality rates declined by 34.4% (from 17.5 to 11.5 per 100 000) for transport injuries, and by 47.7% (from 15.9 to 8.3 per 100000) for unintentional injuries. However, in low-SDI nations the absolute number of deaths increased (by 80.5% to 42 774 for transport injuries and by 39.4% to 31 961 for unintentional injuries). In the high-SDI quintile in 2010-19, the rate per 100 000 of transport injury DALYs was reduced by 16.7%, from 838 in 2010 to 699 in 2019. This was a substantially slower pace of reduction compared with the 48.5% reduction between 1990 and 2010, from 1626 per 100 000 in 1990 to 838 per 100 000 in 2010. Between 2010 and 2019, the rate of unintentional injury DALYs per 100 000 also remained largely unchanged in high-SDI countries (555 in 2010 vs 554 in 2019; 0.2% reduction). The number and rate of adolescent deaths and DALYs owing to environmental heat and cold exposure increased for the high-SDI quintile during 2010-19. Interpretation As other causes of mortality are addressed, inadequate progress in reducing transport and unintentional injury mortality as a proportion of adolescent deaths becomes apparent. The relative shift in the burden of injury from high-SDI countries to low and low-middle-SDI countries necessitates focused action, including global donor, government, and industry investment in injury prevention. The persisting burden of DALYs related to transport and unintentional injuries indicates a need to prioritise innovative measures for the primary prevention of adolescent injury

Global, regional, and national burden of diabetes from 1990 to 2021, with projections of prevalence to 2050: a systematic analysis for the Global Burden of Disease Study 2021

Background: Diabetes is one of the leading causes of death and disability worldwide, and affects people regardless of country, age group, or sex. Using the most recent evidentiary and analytical framework from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD), we produced location-specific, age-specific, and sex-specific estimates of diabetes prevalence and burden from 1990 to 2021, the proportion of type 1 and type 2 diabetes in 2021, the proportion of the type 2 diabetes burden attributable to selected risk factors, and projections of diabetes prevalence through 2050. Methods: Estimates of diabetes prevalence and burden were computed in 204 countries and territories, across 25 age groups, for males and females separately and combined; these estimates comprised lost years of healthy life, measured in disability-adjusted life-years (DALYs; defined as the sum of years of life lost [YLLs] and years lived with disability [YLDs]). We used the Cause of Death Ensemble model (CODEm) approach to estimate deaths due to diabetes, incorporating 25 666 location-years of data from vital registration and verbal autopsy reports in separate total (including both type 1 and type 2 diabetes) and type-specific models. Other forms of diabetes, including gestational and monogenic diabetes, were not explicitly modelled. Total and type 1 diabetes prevalence was estimated by use of a Bayesian meta-regression modelling tool, DisMod-MR 2.1, to analyse 1527 location-years of data from the scientific literature, survey microdata, and insurance claims; type 2 diabetes estimates were computed by subtracting type 1 diabetes from total estimates. Mortality and prevalence estimates, along with standard life expectancy and disability weights, were used to calculate YLLs, YLDs, and DALYs. When appropriate, we extrapolated estimates to a hypothetical population with a standardised age structure to allow comparison in populations with different age structures. We used the comparative risk assessment framework to estimate the risk-attributable type 2 diabetes burden for 16 risk factors falling under risk categories including environmental and occupational factors, tobacco use, high alcohol use, high body-mass index (BMI), dietary factors, and low physical activity. Using a regression framework, we forecast type 1 and type 2 diabetes prevalence through 2050 with Socio-demographic Index (SDI) and high BMI as predictors, respectively. Findings: In 2021, there were 529 million (95% uncertainty interval [UI] 500-564) people living with diabetes worldwide, and the global age-standardised total diabetes prevalence was 6·1% (5·8-6·5). At the super-region level, the highest age-standardised rates were observed in north Africa and the Middle East (9·3% [8·7-9·9]) and, at the regional level, in Oceania (12·3% [11·5-13·0]). Nationally, Qatar had the world's highest age-specific prevalence of diabetes, at 76·1% (73·1-79·5) in individuals aged 75-79 years. Total diabetes prevalence-especially among older adults-primarily reflects type 2 diabetes, which in 2021 accounted for 96·0% (95·1-96·8) of diabetes cases and 95·4% (94·9-95·9) of diabetes DALYs worldwide. In 2021, 52·2% (25·5-71·8) of global type 2 diabetes DALYs were attributable to high BMI. The contribution of high BMI to type 2 diabetes DALYs rose by 24·3% (18·5-30·4) worldwide between 1990 and 2021. By 2050, more than 1·31 billion (1·22-1·39) people are projected to have diabetes, with expected age-standardised total diabetes prevalence rates greater than 10% in two super-regions: 16·8% (16·1-17·6) in north Africa and the Middle East and 11·3% (10·8-11·9) in Latin America and Caribbean. By 2050, 89 (43·6%) of 204 countries and territories will have an age-standardised rate greater than 10%. Interpretation: Diabetes remains a substantial public health issue. Type 2 diabetes, which makes up the bulk of diabetes cases, is largely preventable and, in some cases, potentially reversible if identified and managed early in the disease course. However, all evidence indicates that diabetes prevalence is increasing worldwide, primarily due to a rise in obesity caused by multiple factors. Preventing and controlling type 2 diabetes remains an ongoing challenge. It is essential to better understand disparities in risk factor profiles and diabetes burden across populations, to inform strategies to successfully control diabetes risk factors within the context of multiple and complex drivers. Funding: Bill & Melinda Gates Foundation