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Understanding the structural evolution of the South Dezful Embayment (SDE) in the Zagros Fold-and-Thrust Belt (ZFTB) is significant for hydrocarbon exploration and production. The structural evolution of this area has been controlled by the reactivation of basement structures related to the oblique convergence along the ZFTB. In this work, we study the effect of the pre-contractional interaction between the basement step and overlaid salt layer superimposed by the Zagros shortening on the structural style and evolution of the sedimentary basin in the SDE. We use multidisciplinary approaches involving surface and subsurface data and analogue models. Disharmonic folds with small wavelength formed over the Kharg-Mish Palaeo-high (KMPH) where the sedimentary cover is thinner. On the other hand, faulted detachment folds with large wavelengths developed in the adjacent depocenters. Furthermore, the KMPH affected the geometry and kinematics of the frontal part of the Zagros Belt, which is characterized by the Mountain Front Flexure (MFF) topographic step. Long-lasting active deformation of the sedimentary cover over the frontal ramp of the KMPH developed the South Izeh Promontory (SIP). Localized contraction in the SIP was accommodated temporally by trishear fault-propagation folding and resulted in > 5 km elevation difference between this promontory and two adjacent local basins. Supporting scaled analogue models show that structural evolution, folding and along-strike variations in fold style of the SDE have been controlled by thickness variations of the sedimentary cover and the geometry of the inherited pre-salt structure. Based on the results of this study, the effect of inherited structural highs on the structure and kinematics of the SDE provide important insights for hydrocarbon entrapment, migration and exploration.

Introduction: To evaluate the biological interaction between dental stem cells (DSCs) and different growth factors in the field of regenerative endodontics. Methods: A systematic search was conducted in the electronic databases up to October 2021. This study followed the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. Ex vivo studies evaluating the biological interactions of DSCs and growth factors were included. The meta-analysis was performed according to the type of growth factor. The outcomes were cell viability/proliferation and mineralization. Standardized mean differences (SMDs) were estimated using the random-effect maximum-likelihood method (P Results: Twenty articles were included in the systematic review; meta-analysis was performed for fibroblast growth factor-2 (FGF-2) and Transforming growth factor-ß1 (TGF-ß1) (n=5). Results showed that use of FGF-2 significantly increased cell proliferation on day 1-(SMD=3.56,P=0.00), 3-(SMD=9.04,P=0.00), 5-(SMD=8.37,P=0.01), and 7 (SMD=8.51,P=0.00) than the control group. TGF-ß1 increased alkaline phosphatase (ALP) activity more than control only on day 3 (SMD=3.68,P=0.02). TGF-ß1 had no significant effect on cell proliferation on days 1 and 3 (P>0.05) and on ALP activity on days 5 and 7 (P>0.05). Meta-regression analysis showed that different covariates (i.e., cell type, passage number, and growth factors' concentration) could significantly influence the effect sizes at different follow-ups (P Conclusion: Specific growth factors might enhance the proliferation and mineralization of DSCs; however, the obtained evidence was weak. Due to the high heterogeneity among the included studies, other growth factors' inhibitory/stimulatory effects on DSCs could not be evaluated.

Objective: The current systematic review aims to provide the available ex vivo evidence evaluating the biological interactions of dental stem cells (DSCs) and growth factor delivery systems. Methodology: Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a systematic search was conducted in the electronic databases (PubMed/Medline, Scopus, Web of Science, and Google Scholar) up to January 2022. Studies evaluating the biological interactions of DSCs and growth factor delivery systems were included. The outcome measures were cell cytocompatibility, mineralization, and differentiation. Results: Sixteen studies were selected for the qualitative synthesis. The following growth factor delivery systems exhibit adequate cytocompatibility, enhanced mineralization, and osteo/odontoblast differentiation potential of DSCs: 1) Fibroblast growth factor (FGF-2)-loaded-microsphere and silk fibroin, 2) Bone morphogenic protein-2 (BMP-2)-loaded-microsphere and mesoporous calcium silicate scaffold, 3) Transforming growth factor Betha 1 (TGF-ß1)-loaded-microsphere, glass ionomer cement (GIC), Bio-GIC and liposome, 4) TGF-ß1-loaded-nanoparticles/scaffold, 5) Vascular endothelial growth factor (VEGF)-loaded-fiber and hydrogel, 6) TGF-ß1/VEGF-loaded-nanocrystalline calcium sulfate/hydroxyapatite/calcium sulfate, 7) Epidermal growth factor-loaded- nanosphere, 8) Stem cell factor/DSCs-loaded-hydrogel and Silk fibroin, 9) VEGF/BMP-2/DSCs-loaded-Three-dimensional matrix, 10) VEGF/DSCs-loaded-microsphere/hydrogel, and 11) BMP-2/DSCs and VEGF/DSCs-loaded-Collagen matrices. The included delivery systems showed viability, except for Bio-GIC on day 3. The choice of specific growth factors and delivery systems (i.e., BMP-2-loaded-microsphere and VEGF-loaded-hydrogel) resulted in greater gene expression. Conclusions: This study, with low level evidence obtained from ex vivo studies, suggests that growth factor delivery systems induce cell proliferation, mineralization, and differentiation towards a therapeutic potential in regenerative endodontics.

To evaluate the biological interaction between dental stem cells (DSCs) and different growth factors in the field of regenerative endodontics.A systematic search was conducted in the electronic databases up to October 2021. This study followed the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. Ex vivo studies evaluating the biological interactions of DSCs and growth factors were included. The meta-analysis was performed according to the type of growth factor. The outcomes were cell viability/proliferation and mineralization. Standardized mean differences (SMDs) were estimated using the random-effect maximum-likelihood method (P.05). Additional analysis was performed to find any potential source of heterogeneity.Twenty articles were included in the systematic review; meta-analysis was performed for fibroblast growth factor-2 (FGF-2) and Transforming growth factor-ß1 (TGF-ß1) (n=5). Results showed that use of FGF-2 significantly increased cell proliferation on day 1-(SMD=3.56,P=0.00), 3-(SMD=9.04,P=0.00), 5-(SMD=8.37,P=0.01), and 7 (SMD=8.51,P=0.00) than the control group. TGF-ß1 increased alkaline phosphatase (ALP) activity more than control only on day 3 (SMD=3.68,P=0.02). TGF-ß1 had no significant effect on cell proliferation on days 1 and 3 (P0.05) and on ALP activity on days 5 and 7 (P0.05). Meta-regression analysis showed that different covariates (i.e., cell type, passage number, and growth factors' concentration) could significantly influence the effect sizes at different follow-ups (P0.05).Specific growth factors might enhance the proliferation and mineralization of DSCs; however, the obtained evidence was weak. Due to the high heterogeneity among the included studies, other growth factors' inhibitory/stimulatory effects on DSCs could not be evaluated.

The study aims to evaluate the effect of bone morphogenetic protein-2 (BMP-2) and transforming growth factor-beta 1 (TGF-β1) co-stimulation on odontogenic differentiation of human dental pulp stem cells (hDPSCs).The viability/proliferation of hDPSCs treated with BMP-2 (group B), TGF-β1 (group T), or BMP-2/TGF-β1 (group BT) were evaluated. The experiments on odontogenic differentiation were done for 14 days. The following subgroups were added to investigate the effect of co-stimulation with different timing: subgroup B1, TGF-β1 co-stimulation in the first week; subgroup B2, TGF-β1 co-stimulation in the second week; subgroup T1, BMP-2 co-stimulation in the first week; and subgroup T2, BMP-2 co-stimulation in the second week. The mineralization was assessed using alizarin red staining. The expression of following genes was assessed using quantitative real-time polymerase chain reaction: dentin sialophosphoprotein (DSPP), dentin matrix protein-1 (DMP1), osteopontin (OPN), and alkaline phosphatase.All groups showed viability similar to the control group (P .05). The greater mineralization was detected in B groups on day 14. The expressions of DSPP, DMP-1, and OPN increased on day 14 (P .05). In the combination groups, the higher expressions of DSPP and DMP-1 were observed in subgroups B1 and B2 than groups B and T (P .05).BMP-2 was the key in odontogenic differentiation of hDPSCs, which was further enhanced by co-stimulation with TGF-β1. Continuous stimulation with TGFβ-1 did not improve the differentiation of hDPSCs.Combined use of the BMP-2 and TGFβ-1 at the specific sequence can provide a tissue engineering approach for the future guided dentin regeneration.

Objectives Pain management during endodontic therapy is an important issue in clinical practice. The objective of this systematic review and meta-analysis was to evaluate the efficacy of occlusal reduction to control the post-operative endodontic pain in adults undergoing root canal therapy. Materials and methods Electronic database and manual searches of English papers were conducted up to August 2019 to identify randomised placebo-controlled trials. The MeSH terms used were (endodontics OR root canal therapy) AND (postoperative pain) AND (occlusal reduction). The primary outcome measure was the post-operative pain intensity up to 72 hours. Pooled standardised mean differences (SMDs) and 95% confidence intervals (CIs) were calculated using random-effects inverse variance method. The statistical heterogeneity was assessed using the Cochrane Q test. The significance level was set at P Results In total, six randomised controlled trials including 344 participants were included. Our meta-analyses showed that relief of occlusal surface did not significantly reduce the pain intensity scores at 12- (SMD = -0.46; 95% CI = -1.24, 0.30; P = .239), 24- (SMD = -0.17; 95% CI = -0.73, 0.38; P = .533) and 48- (SMD = -0.67; 95% CI = -1.38, 0.03; P = .063) when compared to placebo. However, at 72 hours, patients received intervention showed significant more pain reduction than placebo groups (SMD = -1.07; 95% CI = -1.81, -0.32; P = .005). Conclusion Based on this meta-analysis, the efficacy of occlusal reduction in post-endodontic pain control for up to 2 days is not supported. However, on day three, it had a positive influence on the control of post-endodontic pain.

Objectives The current systematic review and meta-analysis aimed to assess the efficacy of prophylactic oral antibiotics in the management of post-operative endodontic symptoms in adults with necrotic pulp. Materials and methods A systematic search up to April 2020 was performed to find all randomised controlled trials (RTCs) comparing oral antibiotics with placebo to manage post-endodontic symptoms. The outcome measures were post-operative pain, swelling and/or the combined pain and swelling at different follow-ups. Standardised mean differences (SMDs) and 95% confidence intervals (CIs) were estimated using random-effect inverse-variance method. Additional analysis was performed if heterogeneity existed (P Results For post-endodontic pain, 8 RCTs (n = 690) were included. Antibiotic prescription had no significant effect on endodontic pain at 6 (SMD = -0.008, 95% CI -0.279 - 0.264, P = .95), 12 (SMD = -0.080, 95% CI -1.39 - 1.23, P = .90), 24 (SMD = -0.044, 95% CI -0.29 - 0.20, P = .72), 48 (SMD = 0.18, 95% CI -0.26 - 0.62, P = .42) and 72 h (SMD= -0.050, 95% CI -0.33 - 0.23, P = .723) post-operatively. For post-endodontic swelling, 4 RCTs (n = 149) were included. Antibiotic prescription had no significant effect on endodontic swelling at 24 (SMD = 0.29, 95% CI -0.72 - 1.32, P = .56), 48 (SMD = -0.23, 95% CI -0.98 - 0.51, P = .54) and 72 hours (SMD= -0.03, 95% CI -1.25 - 1.33, P = .96), post-operatively. For combined pain and swelling, no meta-analysis was performed. Conclusion The administration of prophylactic antibiotics to prevent post-operative endodontic symptoms is not supported by the current evidence.

In late December 2019, a new type of coronavirus, called novel coronavirus disease 2019 (COVID-19), caused a major outbreak of severe pneumonia in Wuhan (Huanan seafood market) and then, across China. As of 31 March 2020, COVID-19 has spread in 200 countries, including Iran, and imposed serious health-related threats to the public worldwide. Fever, dry (non-productive) cough, myalgia, and pneumonia seem to be the symptoms of COVID-19 disease. To date, and despite various studies and investigations, except for chloroquine and hydroxychloroquine, which have recently been temporarily approved by FDA, no other vaccines and/or antiviral agents have been clinically endorsed for the treatment of COVID-19 disease. Nevertheless, prevention of the disease and control of the infection is deemed a top priority for the general public. Owing to the characteristics of different dental treatments and settings, the risk of virus transmission can be considered high between patients and dental practitioners. Therefore, the need for strict and tough effective infection control protocols in dental practice is of great importance, namely for the dental centers in the potentially affected areas with COVID-19. This study, based on relevant evidence, aimed to review the basic knowledge of COVID-19 and address the recommended protocols of infection control for the dental practitioners and treatments in hypothetically stricken areas.

Polymer networks are considered to be largely affected by water and chemical absorption from environment. Objective: The aim of this study was to evaluate the hygroscopic expansion of bulk-fill composite. Material and Methods: Fifteen disks (5 in each group) with different thickness(4mm/2mm) of Tetric N-Ceram Bulk Fill composite(TB) and Tetric N-Ceram composite(TN) were made according to the manufacturer’s instruction and stored in deionized water. The length of each specimen was recorded using a digital micrometer at baseline and at the end of 24 h, 1, 2, 4, 12 weeks intervals. Repeated measure ANOVA and Tukey HSD were used to determine the effect of variables. At 12 weeks, the mean hygroscopic expansion after water immersion ranged between 0. 33±0.09mm for TN to 0.41±0.07mm for TB with 2mm thickness. Repeated measure ANOVA revealed a significant increase in hygroscopic expansion over time (P

Summary The objective of this review was to evaluate the efficacy of non-narcotic analgesics including non-steroidal anti-inflammatory drugs (NSAIDs) and/or paracetamol in the treatment of post-operative endodontic pain. Additionally, we aimed to examine the possible association of study covariates on the pain scores using meta-regression analysis. An electronic search was performed in 2016. After data extraction and quality assessment of the included studies (n = 27, representing 2188 patients), meta-analysis was performed using a random-effect inverse variance method. Meta-regression analysis was conducted to examine the associations between effect sizes and study-level covariates (P

Introduction: Frailty models were utilized in survival models to take into account created heterogeneity and dependence between experimental units. Parametric and semi-parametric methods are considered for estimation of parameters in frailty models. In parametric frailty models, to frailty and baseline hazard, a parametric distribution is assumed, while the distribution for baseline hazard function is not considered in semi-parametric methods. Besides, the parameters using EM algorithm or penalized likelihood are estimated in the mentioned methods. The purpose of this study is the comparison of parametric and semi-parametric methods in frailty models. Materials and Methods: Two hundred thirteen of the warfare victims that treated with dental implants during 2000 to 2010 were enrolled in this study. In order to investigation effective factors in survival of the dental implants placement, frailty models are fitted. Parameters are estimated using the three methods, parametric approach, semi- parametric using EM algorithm and Semi parametric using penalized likelihood. Statistical analysis was carried out using Frailtypack package in R software version 3.3.1. Results: Estimation of the semi parametric using penalized likelihood approach is contained a smaller magnitude of AIC as compared to parametric and semi-parametric approach of EM algorithm. Smoking and implant length are significant factors on survival implants (p

Objectives This study aimed to evaluate the ability of lithium disilicate ceramics to reproduce the A2 shade and to mask A4 substrates. Materials and Methods Twenty-four discs (8 mm in diameter, shade A2) of high translucency (groups 1-3) and low translucency (groups 4-6) of IPS e.max ceramic with different thicknesses (0.5, 0.75, and 1 mm) were fabricated as monolithic structures. In addition, discs of medium opacity (group 7-8) with different core/veneer combinations (0.3 mm/0.7 mm and 0.5 mm/0.5 mm) were fabricated as bilayer structures. Specimens were superimposed on an A4 substrate (complex). The color changes of the complex were measured using a spectrophotometer on a black background, and the ΔE values of the complex were compared with either the A4 substrate or the A2 shade tab. One-way analysis of variance, the Tukey honest significant difference test, and the Fisher test were used to analyze the data (p < 0.05). Results Significant between-group differences were found for comparisons to both the A4 substrate and the A2 shade (p < 0.05). When compared with the A4 substrate, the ΔE values in all groups were in the non-acceptable range. When compared with the A2 shade, the ΔE values in all groups, except groups 2 and 3, were in the clinically acceptable range. Conclusions All translucencies and thicknesses masked the underlying dark substrate. However, the low-translucency IPS e.max Press better reproduced the A2 shade.