Humoral immune response to two doses of COVID-19 mRNA-based vaccines in people living with HIV: A systematic review and meta-analysis.

People living with HIV (PLWH) are susceptible to severe COVID-19 infection and hence this fragile population has prioritised vaccination. This systematic review and meta-analysis aimed to assess the humoral immune response after receiving two doses schedule of COVID-19 mRNA vaccinations in this high-risk population. A systematic electronic search on the PubMed database and manual searches were performed for relevant articles until 30 Sep 2022. Two outcomes of interest were seroconversion rates and anti-spike receptor binding domain (anti-S-RBD) antibody titres at the median time of 14-35 days following two-dose vaccination among PLWH. Nineteen cohorts and one cross-sectional study were eligible for inclusion in this study. The pooled estimate of seroconversion rate after receiving two doses of mRNA vaccination schedule were 98.4% and 75.2% among PLWH with CD4>500 cells/mm3 and CD4<200 cells/mm3 , respectively. Compared with controls, PLWH with CD4>500 cells/mm3 had a 51% likelihood of having positive anti-Spike-RBD immunoglobulin G (IgG) (OR: 0.509, 95% CI: 0.228, 1.133, p = 0.098) post-vaccination and this value was only 1.4% (OR: 0.014, 95% CI: 0.002, 0.078, p = 0.000) for PLWH with CD4<200 cells/mm3 . There was no significant difference in titres of antibodies on 14-35 days post-vaccination between PLWH with CD4>500 cells/mm3 and healthy controls (p = 0.06). The pooled median of anti-S-RBD IgG values were 1461.93 binding antibody units (BAU)/ml and 457.41 BAU/ml in PLWH with CD4>500 cells/mm3 and CD4<200 cells/mm3 , respectively. According to these findings, vaccination with both Pfizer-BioNTech and Moderna vaccines induced a robust humoral response in ART-treated HIV patients with preserved CD4 cell count. A diminished humoral immune response to vaccination against COVID-19 in PLWH with unrestored CD4 count implied the need of specific vaccination schemes.

The maternal factors associated with infant low birth weight: an umbrella review.

BACKGROUND: In this umbrella review, we systematically evaluated the evidence from meta-analyses and systematic reviews of maternal factors associated with low birth weight. METHODS: PubMed, Scopus, and Web of Science were searched to identify all relevant published studies up to August 2023. We included all meta-analysis studies (based on cohort, case-control, cross-sectional studies) that examined the association between maternal factors (15 risk factors) and risk of LBW, regardless of publication date. A random-effects meta-analysis was conducted to estimate the summary effect size along with the 95% confidence interval (CI), 95% prediction interval, and heterogeneity (I2) in all meta-analyses. Hedges' g was used as the effect size metric. The effects of small studies and excess significance biases were assessed using funnel plots and the Egger's test, respectively. The methodological quality of the included studies was assessed using the AMSTAR 2 tool. RESULTS: We included 13 systematic Review with 15 meta-analysis studies in our study based on the inclusion criteria. The following 13 maternal factors were identified as risk factors for low birth weight: crack/cocaine (odds ratio [OR] 2.82, 95% confidence interval [CI] 2.26-3.52), infertility (OR 1.34, 95% CI 1.2-1.48), smoking (OR 2.00, 95% CI 1.76-2.28), periodontal disease (OR 2.41, 95% CI 1.67-3.47), depression (OR 1.84, 95% CI 1.34-2.53), anemia (OR 1.32, 95% CI 1.13-1.55), caffeine/coffee (OR 1.34, 95% CI 1.14-1.57), heavy physical workload (OR 1.87, 95% CI 1.00-3.47), lifting ≥ 11 kg (OR 1.59, 95% CI 1.02-2.48), underweight (OR 1.79, 95% CI 1.20-2.67), alcohol (OR 1.23, 95% CI 1.04-1.46), hypertension (OR 3.90, 95% CI 2.73-5.58), and hypothyroidism (OR 1.40, 95% CI 1.01-1.94). A significant negative association was also reported between antenatal care and low birth weight. CONCLUSIONS: This umbrella review identified drug use (such as crack/cocaine), infertility, smoking, periodontal disease, depression, caffeine and anemia as risk factors for low birth weight in pregnant women. These findings suggest that pregnant women can reduce the risk of low birth weight by maintaining good oral health, eating a healthy diet, managing stress and mental health, and avoiding smoking and drug use.

Hospital mortality prediction in traumatic injuries patients: comparing different SMOTE-based machine learning algorithms.

BACKGROUND: Trauma is one of the most critical public health issues worldwide, leading to death and disability and influencing all age groups. Therefore, there is great interest in models for predicting mortality in trauma patients admitted to the ICU. The main objective of the present study is to develop and evaluate SMOTE-based machine-learning tools for predicting hospital mortality in trauma patients with imbalanced data. METHODS: This retrospective cohort study was conducted on 126 trauma patients admitted to an intensive care unit at Besat hospital in Hamadan Province, western Iran, from March 2020 to March 2021. Data were extracted from the medical information records of patients. According to the imbalanced property of the data, SMOTE techniques, namely SMOTE, Borderline-SMOTE1, Borderline-SMOTE2, SMOTE-NC, and SVM-SMOTE, were used for primary preprocessing. Then, the Decision Tree (DT), Random Forest (RF), Naive Bayes (NB), Artificial Neural Network (ANN), Support Vector Machine (SVM), and Extreme Gradient Boosting (XGBoost) methods were used to predict patients' hospital mortality with traumatic injuries. The performance of the methods used was evaluated by sensitivity, specificity, Positive Predictive Value (PPV), Negative Predictive Value (NPV), accuracy, Area Under the Curve (AUC), Geometric Mean (G-means), F1 score, and P-value of McNemar's test. RESULTS: Of the 126 patients admitted to an ICU, 117 (92.9%) survived and 9 (7.1%) died. The mean follow-up time from the date of trauma to the date of outcome was 3.98 ± 4.65 days. The performance of ML algorithms is not good with imbalanced data, whereas the performance of SMOTE-based ML algorithms is significantly improved. The mean area under the ROC curve (AUC) of all SMOTE-based models was more than 91%. F1-score and G-means before balancing the dataset were below 70% for all ML models except ANN. In contrast, F1-score and G-means for the balanced datasets reached more than 90% for all SMOTE-based models. Among all SMOTE-based ML methods, RF and ANN based on SMOTE and XGBoost based on SMOTE-NC achieved the highest value for all evaluation criteria. CONCLUSIONS: This study has shown that SMOTE-based ML algorithms better predict outcomes in traumatic injuries than ML algorithms. They have the potential to assist ICU physicians in making clinical decisions.

Statistical shape analysis of maxillary palatal morphology in patients with palatally displaced canines.

OBJECTIVE: Maxillary morphology has long been a subject of interest due to its possible impact on palatally and labially displaced canines. This study aims to conduct a comparison of the palate morphology between individuals with palatal and labially displaced canines and control subjects using statistical shape analysis on a coronal cross-sectional of CBCT images. MATERIALS AND METHODS: Patients aged between 12 and 43 years with palatally or labially displaced canines referred to Hamadan School of Dentistry between 2014 and 2019 were recruited for this retrospective study. The sample included 29 palatally displaced canines (PDC), 20 labially displaced canines (LDC), and 20 control groups (CG). Initially, the maxillary palate coronal section was acquired and landmarked in the region between the right and the left first molar. Procrustes and principal component analyses were used to identify the primary patterns of palatal shape variation. Statistical tests were then performed to examine both shape and size differences. RESULTS: According to the results of Hotelling's T2 test, there is a significant difference between the mean shape of palate in PDC and CG (P = 0.009), while the difference between the PDC-LDC and LDC-CG groups is not significant. The longest full Procrustes distance was observed between PDC and CG (distance = 0.043), and the shortest full Procrustes distance was observed between LDC and CG (distance = 0.029). The first two principal components accounted for 84.47% of the total variance. The predictive accuracy of the discriminant analysis model showed that 72.46% of cases were correctly classified into the three study groups. CONCLUSIONS: In terms of centroid size, there was no significant difference in the sectional area between the three groups, but the difference between the mean shape of palate in the PDC and CG groups was significant. The PDC group showed more prominent mid-palatal area in the molar region.

Effect of photobiomodulation therapy with different wavelengths on bone mineral density in osteoporotic rats.

Osteoporosis is associated with severe pain, bone deformity, fracture, and bone loss. It is important to find strategies to prevent bone resorption and treat osteoporosis. This study sought to assess the effect of photobiomodulation therapy (PBMT) with different wavelengths on bone mineral density (BMD) in osteoporotic rats. This animal study evaluated 63 adult female rats. The rats underwent ovariectomy to induce osteoporosis. Ovariectomized rats were randomly divided into 9 groups of control (OC), treatment with zoledronic acid alone (0.02 mg/kg), and treatment with 660 nm, 810 nm, and 940 nm PBMT alone (3 times a week for 6 weeks, energy density of 4 J/cm2), and combined with zoledronic acid. The healthy control group (HC) only underwent sham surgery. The rats underwent cone-beam computed tomography (CBCT) 52 days after the first treatment session to measure their BMD according to the gray value (GV) of images. To assess the biomechanical properties of bone, the resected bones were subjected to 3-point bending test (3-PBT). The experimental groups had significant differences with the OC group regarding radiographic and biomechanical properties of bone (P < 0.05), indicating a healing course. No significant difference was noted between the experimental groups treated with different laser wavelengths and those treated with zoledronic acid (P > 0.05). In the condition of this study, it was found that PBMT at a constant energy density of 4 J/cm2 with 660-, 810-, and 940-nm wavelengths is effective for enhancement of bone mineral density and biomechanical properties. No significant difference was noted between different wavelengths of diode laser regarding radiographic and biomechanical properties of bone.

Sotrovimab therapy in solid organ transplant recipients with mild to moderate COVID-19: a systematic review and meta-analysis.

Purpose: Solid organ transplant recipients (SOTR) have a high risk for severe COVID-19 infection; hence it is necessary to find alternative treatment strategies to protect these patients from the complications caused by the severe progression of the disease. This study aimed to determine the effectiveness of sotrovimab among SOTR with COVID-19.Materials and methods: A systematic literature search was conducted with relevant keywords to find studies that reported clinical outcomes regarding sotrovimab administration in SOTR outpatients with confirmed COVID-19 infection, who had mild-to-moderate symptoms.Results: Of 796 records found by a systematic search, only 14 met the inclusion criteria for reporting in a systematic review and only 6 enrolled in a meta-analysis. This meta-analysis indicated that SOTR outpatients with mild to moderate COVID-19 who received sotrovimab had lower likelihood of all-cause hospitalization (OR: 0.29, CI: 0.16, 0.52, p < 0.001), ICU admission (OR: 0.17, CI: 0.05, 0.64, p = 0.009) and mortality (OR: 0.15, CI: 0.03, 0.64, p = 0.010) within 30 days of drug infusion compared to controls.Conclusions: Our findings confirm that monoclonal antibody therapy with sotrovimab in SOTR is associated with better outcomes and consequently a reduced risk of disease progression in this high-risk population.

Association between the severity of periodontitis, COVID-19, C-reactive protein and interleukin-6 levels in hospitalized patients: a case‒control study.

BACKGROUND: The COVID-19 pandemic is perhaps one of the most important events of the 21st century. Periodontitis is one of the most prevalent diseases of the oral cavity. Due to possible pathways of interaction between these two diseases, we investigated their association. METHODS: The study population consisted of hospitalized patients with established COVID-19 diagnoses. Patients with mild to moderate COVID-19 were considered controls, while cases had severe to critical COVID-19. Periodontal examination and serum and saliva sampling were performed for each patient. Relevant medical data were extracted from patients' hospital files. RESULTS: Of the enrolled patients, 122 were included in the statistical analyses. The severity of periodontitis was directly and significantly correlated with the severity of COVID-19 (P < 0.001). Patients with generalized stage III or IV periodontitis displayed an adjusted odds ratio of 4.24 for severe to critical COVID-19. Salivary and serum interleukin-6 levels were significantly associated with COVID-19 severity (P values: 0.002 and 0.004, respectively). Hospitalization length was significantly associated with the severity of periodontitis (P = 0.004). Clinical attachment level and gingival index were associated with increased odds for adverse events (P values: 0.004 and 0.035, respectively), while number of remaining teeth was associated with decreased odds for adverse events (P = 0.023). CONCLUSIONS: This study showed that the severity of periodontitis is associated with the severity of COVID-19. This association might manifest as increased odds of adverse events. COVID-19 severity was associated with higher levels of salivary and serum interleukin-6 levels.

Hematologic tests and their association with the severity of COVID-19 and periodontitis in hospitalized patients: a case-control study.

BACKGROUND: The presence of comorbidities, especially those with a chronic inflammatory nature such as periodontitis, can facilitate COVID-19 progression toward more severe forms. Both of these diseases can affect systemic health and alter hematological test results. In this study, we decided to investigate COVID-19 and periodontitis' possible interaction with these alterations. METHODS: Hospitalized patients with a definitive diagnosis of COVID-19 were included. Controls had mild to moderate COVID-19, while cases had severe to critical COVID-19. Periodontal examination was done for each patient. Relevant medical and hematological data were extracted from patient's hospital files. RESULTS: A total of 122 patients entered the final analysis. The minimum white blood cell counts were associated with the severity of periodontitis. The interaction between periodontitis and COVID-19 was associated with increased minimum white blood cell counts and decreased platelet counts. COVID-19 severity was associated with increased venous oxygen saturation, prothrombin time, the maximum partial thromboplastin time, the maximum and average urea, the maximum creatinine, the maximum potassium, and lactate dehydrogenase, and decreased sodium levels. CONCLUSIONS: Results of this study showed that several blood parameters were associated with periodontitis, COVID-19, or the interaction between them.

The effect of low-dose aspirin on aspirin triggered lipoxin, interleukin 1 beta, and prostaglandin E2 levels in periapical fluid: a double-blind randomized clinical trial.

BACKGROUND: The role of pro-resolving mediators in inflammation is a new concern in research. The effect of low-dose aspirin on production of a special kind of these mediators named aspirin triggered lipoxin (ATL) has been studied on different tissues. This randomized clinical trial evaluated the effect of low-dose aspirin on ATL and pro-inflammatory mediators' level in periapical fluid of necrotic teeth with large lesions. METHODS: Twenty-four patients with necrotic pulp and periapical lesion were randomly assigned to low-dose aspirin and placebo groups. In the first appointment, canals were shaped up to F3 size and #40 K-file and cleaned with 10 milliliters 2.5% sodium hypochlorite and 17% Ethylenediaminetetraacetic acid. Periapical fluid was sampled by a paper cone. The tooth was temporized without any intracanal medication. Tablets were administered for 7 days, then the teeth were re-opened and the sampling were repeated. Interleukin-1 beta (IL-1ß), prostaglandin E2 (PGE2) and ATL were analyzed by enzyme-linked immunosorbent assay. Data were analyzed with paired t-test using SPSS statistical software, version 21 (α = 0.05). RESULTS: A significant reduction in PGE2 and IL-1ß was noted in the aspirin-treated group while an increase in ATL was observed (P < 0.001). There was no significant difference in the mediator scores before and after in the placebo-treated group (P > 0.05). CONCLUSION: Low-dose aspirin can influence the inflammatory process by reducing pro-inflammatory mediators such as PGE2 and IL-1ß, as well as increasing the pro-resolving mediators such as ATL. TRIAL REGISTRATION: IRCT20191211045702N1.

Correlation of Wilms' Tumor 1 (WT1) with Oxidative Stress Markers and Expression of miR-361-5p; New Aspect of WT1 in Breast Cancer.

Breast carcinoma is a heterogeneous disease that affects millions of women worldwide. Wilms' tumor 1 (WT1) is an oncogene that promotes proliferation, metastasis and reduces apoptosis. MicroRNAs (miR) are short noncoding RNAs with a major role in cancer metastasis. In present study, we investigated the association of serum level of WT1 with oxidative stress and expression of miR-361-5p in breast cancer. Serum samples of 45 patients and of 45 healthy women analyzed for protein level of WT1, malondialdehyde (MDA), total oxidant status (TOS), and total antioxidant capacity (TAC). Serum and tissue expression of miR-361-5p in 45 tumor tissues and 45 paired non-tumor adjacent tissues and 45 serum samples of patients and healthy women analyzed by qRT-PCR. Protein levels of WT1 not significantly difference in serum of patients compared to healthy controls. Serum levels of MDA and TOS in patients were higher, but TAC level was lower than healthy controls (p < 0.001). There was a positive correlation between WT1 with MDA and TOS, and a negative correlation between WT1 with TAC in patients. miR-361-5p expression in tumor tissues and serum of patients was lower than non-tumor adjacent tissues and serum of healthy controls, respectively (p < 0.001). Moreover, there was a negative correlation between miR-361-5p and WT1 in patients. The positive correlation between WT1 with MDA and TOS and negative correlation between TAC and miR-361-5p suggests that this gene can play an important role in worse prognoses in breast cancer. Additionally, miR-361-5p may serve as an invasive biomarker for early detection of breast cancer.

Combined Effects of Noise and Hand-transmitted Vibration on Workers' Muscle and Mental Fatigues in a Simulated Construction Operation.

BACKGROUND: The frequent use of hand-held vibrating tools by construction workers exposes them to hand-transmitted vibration (HTV) and noise. This study investigated the effect of combined exposure to HTV and noise on workers' fatigues under simulated work with a typical building destruction tool. METHODS: The repeated measures study was conducted on 40 construction workers exposed to HTV (5 m/s2 rms with frequencies of 31.5, 63, and 125 Hz), HTV (10 m/s2 rms- 31.5 Hz), noise (90 dBA), and concurrent exposure (noise (90 dBA) + HTV (10 m/s2 rms- 31.5 Hz)) with the typical vibrating hand-held tool for 30 minutes. Electromyography signals determined each worker's fatigue level in the Flexor digitorum superficialis (FDS) muscle in two pre- and post-exposure periods. The subjects also filled out the visual analog scale to evaluate mental fatigue severity subjectively. RESULTS: The mean difference of muscle fatigue parameters was significant in all scenarios except for the two scenarios of alone exposure to HTV (5 m/s2 -125 Hz and noise exposure (p-value < 0.05). The mean difference of mental fatigue in all scenarios except for the two scenarios of exposure to HTV (5 m/s2 -125 Hz) and exposure to HTV (5 m/s2 -63 Hz) was significant (p-value < 0.05). The most differences in muscle fatigue parameters (Amplitude = 8.16±5.63, Mean frequency=-4.69±3.78) and mental fatigue (4.97±2.38) were observed in the simultaneous exposure to noise and HTV. CONCLUSION: Noise exposure alone cannot produce remarkable effects on muscle fatigue but can aggravate the effects of vibrations as a consequence of synergistic interaction. However, the role of noise on perceived mental fatigue was more dominant than the HTV. These findings should be considered to adapt the existing exposure limits to actual work conditions.

Evaluation of the Relationship between Family History and Occurrence, Anatomical Location, and Extent of Coronary Artery Disease among Patients Undergoing Coronary Angiography.

Background: A positive family history (FH) of coronary artery disease (CAD) is considered an independent risk factor for developing CAD. However, the relationship between the occurrence, angiographic anatomical location of the stenosis, and extent of CAD and the risk factors in the patients and their relatives is not well defined. Evaluation of this relationship is our main goal in this study. Methods: In this descriptive cross-sectional study, the FH data for CAD and premature death in first-and second-degree relatives, angiographic anatomical location of the stenosis, the extent of CAD in the patients and their relatives, as well as the relationship between other risk factors and the extent of CAD, were collected from 300 adult patients undergoing coronary angiography at Farshchian cardiovascular hospital in Hamadan (Iran) between March 2020 and 2021. SPSS 24 and the chi-square, Fisher exact, and student t tests were used to analyze data. The significance level was considered P < 0.05. Results: Out of 300 patients, 185 (61.7%) were men and 115 (38.3%) were women. A total of 177 patients (59%) in maternal and 82 patients (27.3%) in paternal relatives had an FH of CAD. There was a significant relationship between the severity of coronary artery involvement and risk factors (P < 0.001). Moreover, there was no significant relationship between the location of coronary artery involvement of the right coronary artery, left coronary artery, and left anterior descending artery and the severity of involvement of patients undergoing coronary angiography and their first- and second-degree relatives (P = 0.480). Conclusion: Our findings suggest that there was no significant relationship between the anatomical location of the stenosis and the number of vessels involved and the FH of the patients. In patients with an FH, the extent of CAD significantly increased according to their risk factors for heart disease.

Interpretable generalized neural additive models for mortality prediction of COVID-19 hospitalized patients in Hamadan, Iran.

BACKGROUND: The high number of COVID-19 deaths is a serious threat to the world. Demographic and clinical biomarkers are significantly associated with the mortality risk of this disease. This study aimed to implement Generalized Neural Additive Model (GNAM) as an interpretable machine learning method to predict the COVID-19 mortality of patients. METHODS: This cohort study included 2181 COVID-19 patients admitted from February 2020 to July 2021 in Sina and Besat hospitals in Hamadan, west of Iran. A total of 22 baseline features including patients' demographic information and clinical biomarkers were collected. Four strategies including removing missing values, mean, K-Nearest Neighbor (KNN), and Multivariate Imputation by Chained Equations (MICE) imputation methods were used to deal with missing data. Firstly, the important features for predicting binary outcome (1: death, 0: recovery) were selected using the Random Forest (RF) method. Also, synthetic minority over-sampling technique (SMOTE) method was used for handling imbalanced data. Next, considering the selected features, the predictive performance of GNAM for predicting mortality outcome was compared with logistic regression, RF, generalized additive model (GAMs), gradient boosting decision tree (GBDT), and deep neural networks (DNNs) classification models. Each model trained on fifty different subsets of a train-test dataset to ensure a model performance. The average accuracy, F1-score and area under the curve (AUC) evaluation indices were used for comparison of the predictive performance of the models. RESULTS: Out of the 2181 COVID-19 patients, 624 died during hospitalization and 1557 recovered. The missing rate was 3 percent for each patient. The mean age of dead patients (71.17 ± 14.44 years) was statistically significant higher than recovered patients (58.25 ± 16.52 years). Based on RF, 10 features with the highest relative importance were selected as the best influential features; including blood urea nitrogen (BUN), lymphocytes (Lym), age, blood sugar (BS), serum glutamic-oxaloacetic transaminase (SGOT), monocytes (Mono), blood creatinine (CR), neutrophils (NUT), alkaline phosphatase (ALP) and hematocrit (HCT). The results of predictive performance comparisons showed GNAM with the mean accuracy, F1-score, and mean AUC in the test dataset of 0.847, 0.691, and 0.774, respectively, had the best performance. The smooth function graphs learned from the GNAM were descending for the Lym and ascending for the other important features. CONCLUSIONS: Interpretable GNAM can perform well in predicting the mortality of COVID-19 patients. Therefore, the use of such a reliable model can help physicians to prioritize some important demographic and clinical biomarkers by identifying the effective features and the type of predictive trend in disease progression.

Intelligent prediction of major adverse cardiovascular events (MACCE) following percutaneous coronary intervention using ANFIS-PSO model.

BACKGROUND: This study aimed to use the hybrid method based on an adaptive neuro-fuzzy inference system (ANFIS) and particle swarm optimization (PSO) to predict the long term occurrence of major adverse cardiac and cerebrovascular events (MACCE) of patients underwent percutaneous coronary intervention (PCI) with stent implantation. METHOD: This retrospective cohort study included a total of 220 patients (69 women and 151 men) who underwent PCI in Ekbatan medical center in Hamadan city, Iran, from March 2009 to March 2012. The occurrence and non-occurrence of MACCE, (including death, CABG, stroke, repeat revascularization) were considered as a binary outcome. The predictive performance of ANFIS model for predicting MACCE was compared with ANFIS-PSO and logistic regression. RESULTS: During ten years of follow-up, ninety-six patients (43.6%) experienced the MACCE event. By applying multivariate logistic regression, the traditional predictors such as age (OR = 1.05, 95%CI: 1.02-1.09), smoking (OR = 3.53, 95%CI: 1.61-7.75), diabetes (OR = 2.17, 95%CI: 2.05-16.20) and stent length (OR = 3.12, 95%CI: 1.48-6.57) was significantly predicable to MACCE. The ANFIS-PSO model had higher accuracy (89%) compared to the ANFIS (81%) and logistic regression (72%) in the prediction of MACCE. CONCLUSION: The predictive performance of ANFIS-PSO is more efficient than the other models in the prediction of MACCE. It is recommended to use this model for intelligent monitoring, classification of high-risk patients and allocation of necessary medical and health resources based on the needs of these patients. However, the clinical value of these findings should be tested in a larger dataset.

Comparison of the amount of artifacts induced by zirconium and titanium implants in cone-beam computed tomography images.

BACKGROUND: This study aimed to compare the amount of artifacts induced by the titanium and zirconium implants on cone-beam computed tomography (CBCT) and assess the effect of different exposure settings on the image quality for both materials. METHODS: In this experimental study, 30 zirconium and 30 titanium implants were placed in bovine rib bone blocks. CBCT images were taken in two different fields of view (FOV: 4 × 6 cm2 and 6 × 8 cm2) and at two resolutions (133 µ and 200 µ voxel size). Subsequently, two observers assessed the images and detected the amount of artifacts around the implants through gray values. Data were analyzed by paired t test and independent t test using SPSS 21 and the 0.05 significance level. RESULTS: The results showed that titanium implants caused lower amounts of artifacts than zirconium implants, which was statistically significant (P < 0.001). The larger FOV (6 × 8 cm2) resulted in a lower amount of artifacts in both groups, although the results were only statistically significant in the zirconium group (P < 0.001). The amount of artifacts was increased when using the 133 µ voxel size in both groups, which was only significant in the zirconium group (P < 0.001). CONCLUSION: Our results suggest that zirconium implants induce higher amounts of artifacts than titanium ones. We also concluded that the artifacts could be minimized using the larger FOV and voxel size.

The age and cause decomposition of inequality in life expectancy between Iranian provinces: application of Arriaga method.

BACKGROUND: This study aimed to decompose the age and cause inequality in life expectancy between two Iranian provinces with the highest and the lowest life expectancy using the Arriaga method. METHODS: The required data was extracted from the death registration system (DRS) and statistical center of Iran. First, we calculated life expectancy at birth for 31 provinces of Iran using life tables, and subsequently, two provinces with the highest and the lowest life expectancy were determined. To decompose the age and cause share in the life expectancy gap between the two provinces, we used Arriaga's method. RESULTS: Tehran with 80.09 years and Sistan and Baluchistan with 72.9 years had the highest and the lowest life expectancy among Iranian Provinces respectively. As a result, the life expectancy gap between Tehran and Sistan and Baluchistan was 7.19 years. Results of age decomposition showed that the highest share in the life expectancy gap attributed to the age group under one year (1.25 years). In terms of the cause of death, the highest percentage belonged to hypertensive diseases with a share of 1.77 years. CONCLUSIONS: There is a wide gap between two provinces with the highest and the lowest life expectancy. Age less than one year and hypertensive diseases were major factors in this inequality. Therefore, policy-makers should concentrate on improvement of survival in children and the reduction of hypertensive diseases to promote life expectancy in Sistan and Baluchistan.

Effect of sodium fluoride varnish, Gluma, and Er,Cr:YSGG laser in dentin hypersensitivity treatment: a 6-month clinical trial.

Dentinal hypersensitivity (DH) is a common clinical condition usually associated with exposed dentinal surfaces. The aim of this study was to study the effect of sodium fluoride varnish, Gluma, and Er,Cr:YSGG laser, in the dentin hypersensitivity treatment. One hundred sixty-five teeth with dentin hypersensitivity in 55 patients were involved in this study. Teeth are divided into five groups based on the received treatment (n = 33): G group: Gluma; F group: sodium fluoride varnish (5%); L group: Er,Cr:YSGG laser (wavelength 2780 nm, frequency 20 Hz, power 0.25 W, energy density 44.3 J/cm2, and pulse width of 150 µs at distance of 1 mm for 30 s) which was followed by Er,Cr:YSGG laser; GL group: Gluma + laser; VL group: both sodium fluoride varnish and Gluma, which are common treatments for hypersensitivity, were selected as control groups. The treatment was performed in one session, and the sensitivity to air spray conditioning was recorded after the treatment, at 15 min, 1 week, 1 month, and 6 months as the VAS. Statistical analysis was performed using SPSS Ver. 21 software. One-way ANOVA was used to compare the VAS between all treatment groups at each time-point. One-way repeated measurements ANOVA (RM-ANOVA) and two-way-repeated measurements ANOVA (RM-ANOVA) were used to compare the hypersensitivity of each group and sensitivity of all treatment groups, respectively. Tukey post hoc test was used to compare the groups pairwise. The hypersensitivity between different groups at before and 15 min after the treatment was not significantly different (P = 0.063). The hypersensitivity of all studied groups was decreased after the treatment. The Er,Cr:YSGG laser, alone or in combination with Gluma, in 1 week, 1 month, and 6 month follow-ups, had significantly reduced the hypersensitivity instead of sodium fluoride varnish. All treatments significantly reduced the dentin hypersensitivity up to 6 months. Er,Cr:YSGG laser alone or in combination with Gluma was more effective than sodium fluoride varnish; however, it was not significantly different from other treatments. In a 6-month follow-up of dentine hypersensitivity treatment, Gluma had a significantly higher effect than sodium fluoride. Trial registration: IRCT20190422043343N1. Registered 19 July 2019.

Dentinal tubule blockage using nanobioglass in the presence of diode (980 nm) and Nd:YAG lasers: an in vitro study.

OBJECTIVES: The main objective of this study was to enhance the blockage of dentinal tubules using nanobioglass in the presence of diode (980 nm) and Nd:YAG lasers in order to reduce permeability and dentin hypersensitivity. MATERIALS AND METHODS: Thirty-six dentinal samples were randomly divided into 6 subgroups (n = 6): (A) control, (B) diode laser (980 nm, 3-W), (C) Nd:YAG laser (1064, 1.0-W), (D) nanobioglass, (E) nanobioglass + diode laser (980 nm), (F) nanobioglass + Nd:YAG laser. The average number of open dentinal tubules was qualitatively and quantitatively evaluated by scanning electron microscopy (SEM). Data were evaluated by SPSS software version 22, Kruskal-Wallis test, and Mann-Whitney tests with Bonferoni's correction (α = 0.008). RESULTS: Based on the results of Mann-Whitney test, there was a significant difference in the mean number of open dentinal tubules between the control group and the other groups (p < 0.008). However, the difference among the other groups was not statistically significant (p > 0.008). CONCLUSIONS: Findings of this study showed that high-power laser radiation, such as Nd:YAG and diode (980 nm) alone or with nanobioglass, has a significant effect on the blockage of dentinal tubules. CLINICAL RELEVANCE: Introduction of non-invasive methods with long-term and lasting effect on reducing pain and discomfort caused by dentin hypersensitivity.

Synthesis and characterization of nano bioactive glass for improving enamel remineralization ability of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP).

OBJECTIVE: Nanomaterials with superior properties such as high surface area over volume ratio are widely used in dentistry and medicine. This in vitro study was performed to synthesize and characterize nano bioactive glass (nBG) and to evaluate the effect of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) containing nBG (CPP-ACP@nBG) on enamel remineralization by its application to pH-cycled, synthetically demineralized enamel surfaces. MATERIALS AND METHODS: nBG particles were prepared by sol-gel method. X-ray diffraction pattern (XRD), Fourier-transform infrared spectroscopy (FTIR) and transmittance electron microscopy (TEM) were used for nBG characterization. Synthetic CPP-ACP paste was prepared and nBG particles were added to it. To evaluate the degree of remineralization, 32 healthy human premolars were selected. The samples were randomly divided into 4 groups as: Group 1: Commercial CPP-ACFP (MI paste plus), Group 2: Synthetic casein phosphopeptide-amorphous calcium phosphate containing fluoride (CPP-ACP@F), Group 3: Synthetic CPP/ACP containing nBG (CPP-ACP@nBG), and Group 4: Control (received no treatment). The pastes were then applied on the tooth surfaces for 28 days. The Vickers microhardness of enamel surfaces was evaluated, and enamel surface morphology was assessed using scanning electron microscopy (SEM). RESULTS: X-Ray diffraction pattern (XRD) of the synthesized nBG show its crystalline nature with the Larnite crystalline mode. Transmittance electron microscope (TEM) microimage of the synthesized nBG shows its formation as less that 100 nm spherical nanoparticle with partial agglomeration. Fourier transform infrared spectroscopy (FTIR) confirm the success formation of nBG with high purity. The results of this study showed that microhardness of the experimental groups was significantly higher than the control group (p ≥ 0.05). SEM images showed a layer of hydroxyapatite in the CPP-ACP@nBG, synthetic and commercial CPP-ACP@F remineralized groups. CONCLUSION: The results of this study demonstrated that CPP-ACP@F and CPP-ACP@nBG remineralize the surface of the demineralized enamel. Microhardness of the remineralized enamel in the CPP-ACP@nBG group was higher than synthetic and commercial CPP-ACP@F groups.

Effect of Adding Silver Nanoparticles on the Flexural Strength of Feldspathic Porcelain.

AIM: This study aimed to evaluate the impact of silver nanoparticles (AgNPs) on the flexural strength of feldspathic porcelain. MATERIALS AND METHODS: Eighty bar-shaped ceramic specimens were prepared in five groups, including a control group and four case groups containing 5, 10, 15, and 20% w/w of AgNPs. Each group consisted of 16 specimens. Silver Nanoparticles were synthesized by a simple deposition method. Three-point bending test was used in the universal testing machine (UTM) machine to evaluate the flexural strength of the specimens. The fractured surface of the ceramic samples was analyzed under scanning electron microscopy (SEM). In order to analyze the data obtained, one-way analysis of variance (ANOVA) and Tukey tests were used (p <0.05). RESULTS: The results implied that the average flexural strength of the samples in the control group was 90.97 MPa and for the experimental groups reinforced with 5, 10, 15, and 20% w/w of AgNPs were 89, 81, 76, and 74 MPa, respectively. CONCLUSION: The addition of AgNPs with a certain amount (up to a concentration of 15% w/w) without reducing the flexural strength improves the antimicrobial properties of the materials used and ultimately improves its quality for dental applications. CLINICAL SIGNIFICANCE: The addition of AgNPs can improve the antimicrobial properties and suitability of the materials.