Recent advances in pre-conditioned mesenchymal stem/stromal cell (MSCs) therapy in organ failure; a comprehensive review of preclinical studies

Mesenchymal stem/stromal cells (MSCs)-based therapy brings the reassuring capability to regenerative medicine through their self-renewal and multilineage potency. Also, they secret a diversity of mediators, which are complicated in moderation of deregulated immune responses, and yielding angiogenesis in vivo. Nonetheless, MSCs may lose biological performance after procurement and prolonged expansion in vitro. Also, following transplantation and migration to target tissue, they encounter a harsh milieu accompanied by death signals because of the lack of proper tensegrity structure between the cells and matrix. Accordingly, pre-conditioning of MSCs is strongly suggested to upgrade their performances in vivo, leading to more favored transplantation efficacy in regenerative medicine. Indeed, MSCs ex vivo pre-conditioning by hypoxia, inflammatory stimulus, or other factors/conditions may stimulate their survival, proliferation, migration, exosome secretion, and pro-angiogenic and anti-inflammatory characteristics in vivo. In this review, we deliver an overview of the pre-conditioning methods that are considered a strategy for improving the therapeutic efficacy of MSCs in organ failures, in particular, renal, heart, lung, and liver.

Comparing knowledge and opinions of medical and dental students in the field of pediatric anesthesia

Background and Purpose

Dental treatment under general anesthesia (GA) is one of the common treatment methods today for dental treatment in children, so dentists' point of view in this field is very important. Therefore, the purpose of this study was evaluation the awareness and attitude of pediatric dentists and final-year dental students about dental treatment for children under GA.

Methods

To conduct this study, 150 people, including 75 general dentists (GD) and 75 final-year dental students (FYDS), were randomly selected in Tehran. In this study, a researcher-made questionnaire containing 15 questions (7 awareness questions and 8 attitude questions) was used to evaluate the awareness and attitude of the participants. After extracting the raw results, statistical analysis of the results was done using SPSS-Ver. 22 software.

Results

60% of the participants (90 people) were men and the remaining 40% (60 people) were women. The results showed that the level of awareness of male dentists was significantly higher than that of female dentists (P = 0.015). In addition, although the awareness level of FYDS was lower than GD, this difference was not statistically significant (P = 0.130). The average level of awareness among different age groups had a significant difference (P = 0.009), so the age group of 36-45 years compared to the younger age groups (25-35 years) and the older age groups (36-45 and 55 -46 years), had a higher level of awareness.

Conclusion

According to the findings, it can be concluded that it is necessary to use appropriate educational methods to improve the level of awareness and attitude of children's dentists.

Exosomes derived from mesenchymal stem cells: Heralding a new treatment for periodontitis?

Periodontitis, as a complex inflammatory disorder, is characterized by continuous destruction of the teeth-supporting components, like alveolar bone and periodontal ligament, and affects a great percentage of individuals over the world. Also, this oral disease is linked with multiple serious illnesses, e.g., cardiovascular disorders, diabetes, and oral cancer; thus, exerting efficient therapy for periodontitis is necessary. Unfortunately, the current therapies for the disease (e.g., surgical and nonsurgical methods) have not reflected enough effectiveness against periodontitis. At present, mesenchymal stem cell (MSC)-based remedy has created new hope for curating different diseases; however, MSCs have no capability to engraft into the chosen tissue, and the tumorigenic influences of MSCs are still the main concern. Interestingly, documents have revealed that MSC-derived mediators, like exosomes, which their exploitation is more feasible than intact MSCs, can be an effective therapeutic candidate for periodontitis. Therefore, in this study, we will review evidence in conjunction with their possible curative impacts on periodontitis cases.

SARS-CoV-2-associated gut microbiome alteration; A new contributor to colorectal cancer pathogenesis

The emergence of a novel coronavirus, COVID-19, in December 2019 led to a global pandemic with more than 170 million confirmed infections and more than 6 million deaths (by July 2022). Studies have shown that infection with SARS-CoV-2 in cancer patients has a higher mortality rate than in people without cancer. Here, we have reviewed the evidence showing that gut microbiota plays an important role in health and is linked to colorectal cancer development. Studies have shown that SARS-CoV-2 infection leads to a change in gut microbiota, which modify intestinal inflammation and barrier permeability and affects tumor-suppressor or oncogene genes, proposing SARS-CoV-2 as a potential contributor to CRC pathogenesis

Biosynthesis of Zn-doped CuFe2O4 nanoparticles and their cytotoxic activity

Zn-doped CuFe2O4 nanoparticles (NPs) were eco-friendly synthesized using plant extract. These nanoparticles were characterized by X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy and thermal gravimetric analysis (TGA). SEM image showed spherical NPs with size range less than 30 nm. In the EDS diagram, the elements of zinc, copper, iron, and oxygen are shown. The cytotoxicity and anticancer properties of Zn-doped CuFe2O4 NPs were evaluated on macrophage normal cells and A549 lung cancer cells. The cytotoxic effects of Zn-doped CuFe2O4 and CuFe2O4 NPs on A549 cancer cell lines were analyzed. The Zn-doped CuFe2O4 and CuFe2O4 NPs demonstrated IC50 values 95.8 and 278.4 µg/mL on A549 cancer cell, respectively. Additionally, Zn-doped CuFe2O4 and CuFe2O4 NPs had IC80 values of 8.31 and 16.1 µg/mL on A549 cancer cell, respectively. Notably, doping Zn on CuFe2O4 NPs displayed better cytotoxic effects on A549 cancer cells compared with the CuFe2O4 NPs alone. Also spinel nanocrystals of Zn-doped CuFe2O4 (~ 13 nm) had a minimum toxicity (CC50 = 136.6 µg/mL) on macrophages J774 Cell Line.

Evaluate the Accuracy of the Diagnostic Test of Ultrasound Imaging for Endodontic: A Systematic Review and Meta-analysis

Objective: approximately 6.3% of adult teeth have apical periodontitis; the commonest kinds of periapical lesions are cyst and abscess (55-6%) and granuloma (46-84%). This systematic review and meta-analysis evaluated the accuracy of the diagnostic test of ultrasound imaging for endodontic. Methods: Using the electronic databases, we searched Cochrane Library, PubMed, and Embase for performing a systematic review of literature during the last decade from February 2011 to May 2021. Then, we employed the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool to assess the quality of the obtained investigations included in the present meta-analysis. In order to extract the required data, two reviewers blindly and individually dealt with the data extraction from the respective abstracts and full-texts of investigations. Diagnostic odds ratio, positive and negative likelihood ratio with a confidence interval (CI) of 95%, random-effects model, and REML method have been computed. Moreover, we assessed Meta-analysis using a statistical software called Stata/MP 16, the fastest version of Stata. Results: Totally, 94 topics and abstracts with potential relevance have been obtained in the electronic searches and eight studies required for this systematic review. Specificity and Sensitivity of ultrasonography for diagnosing the periapical granulomas equaled 92% (ES,0.92 95% CI 0.77,1.07) and 89% (ES,0.89 95% CI 0.74,1.04) and specificity and Sensitivity of ultrasonography for diagnosing periapical cyst equaled 92% (ES,0.92 95% CI 0.77,1.07) and 98% (ES,0.92 95% CI 0.83,1.13). Conclusion: Ultrasonography can be one of the alternative tools for differential diagnosis of periapical lesions (cysts and granulomas) with an endodontic origin.

The Effect of Endodontic Infection on the Pathogenesis of the Systematic Disease: A Systematic Review and Meta-analysis

Objective: The results detailed that a few systemic disorders may impact endodontic healing results. A systematic review can complete such analyses to investigate endodontic infection and cardiovascular disease thoroughly. This systematic review and meta-analysis aimed to evaluate the effect of Endodontic Infections on Cardiovascular Disease. Method: Our search strategy was to screen the relevant articles on the electronic databases of Google Scholar, MEDLINE, Cochrane Library, PubMed, ISI, and Embase, published from January 2005 to January 2020. The management of electronic titles was performed using Endnote X9 software. The main keywords for the search process included "Cardiovascular disease OR CVD", "LEO"," Endodontics", "Endodontic Infections" "dental evaluations", "missing teeth", "apical lesions", "bone loss". The current systematic review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Results: Electronic and manual searches resulted in 53 relevant titles and abstracts. Eventually, five publications were eligible for the inclusion criteria required for this systematic review. The risk ratio (RR) was 1, and the 95% certainty interval (CI) was 3.56–15.87; the obtained very low certainty indicated that the lesion of endodontic origin (LEO) might impact Cardiovascular disease (CVD) improvement. Conclusion: Endodontic Infection may or may not exert a few effects on the systemic Cardiovascular disease (CVD), and there was a low level of proof.

Management of Severe Dento-Alveolar Traumatic Injuries in a 9-Year old Boy: A Case Report

Dentoalveolar traumas can lead to various injuries that may result in tooth loss. A suitable treatment plan and appropriate interventions should be performed to maintain the dental function and aesthetics, especially for the anterior teeth. Objective: To report the interventions performed on dentoalveolar trauma on a 9-years old male patient who presented with gingival immersion of the right maxillary central incisor and missing a tooth due to a falling accident. Case Report: The patient had multiple traumatic injuries. The medical and dental history was taken, and the clinical and radiologic examinations were performed. The patient underwent surgical intervention and splinting to take the intruded tooth back into its normal place. Moreover, the teeth with lateral luxation underwent apexification and composite filling. Also, endodontic treatment was performed on the coronal segment of the tooth with root fractures. The patient underwent clinical and radiographic follow-up for 24 months to assure the treatment efficiency and prevent further complications. Conclusion: It was shown that the interventions performed could preserve the function and aesthetics of the patient’s teeth, which can directly impact his quality of life and emotional state in adolescence

Effects of Diode Low-Level Laser Therapy of 810 Nm on Pulpal Anesthesia of Maxillary Premolars: A Double-Blind Randomized Clinical Trial

OBJECTIVE

The purpose of this study was to investigate the pulpal effect of diode low-level laser therapy (LLLT) of 810 nm on the alleviation of pain in patients requiring dental procedures.

METHODS

The current study was a double-blind randomized clinical trial carried out on twenty participants. The electric pulp testing (EPT) was recorded at baseline. Patients were randomly divided into sham laser and laser group respectively receiving low-level laser with placebo and active probes. Low-level laser at 810 nm, 200 MW constant power, 30s irradiation time and energy dose of 6 J was used. The electric pulp testing (EPT) method was again adopted to assess the rate of induced anesthesia. Laser and sham laser treatments were carried out in two different sessions with a one-week interval to ensure avoiding the potential false placebo results. Data were analyzed in SSPS-24 using Chi-square test and t-test. The p-value was set at 0.05.

RESULTS

A low-level laser at 810 nm significantly alleviate EPT-induced pain compared to the pain before laser irradiation (P≤0.001). While the difference of EPT-induced pain before and after sham laser irradiation was not significant in control group (P>0.05). There was no correlation between the anesthetic effects of a laser application at 810 nm and other variables including age and gender (P>0.05).

CONCLUSION

An 810 nm low-level laser is a powerful device for induced anesthesia applications in patients requiring dental procedures. It also lessens the patients' fear of dental procedures.

Evaluation of the relationship between crown size and root canal morphology of mandibular incisors by cone beam computed tomography (CBCT)

Background

The main reason for the failure of endodontic therapy is the incomplete knowledge about the anatomical variation of root canals. One of the most important factors that leads to the failure of root canal treatment, is missed and untreated major root canals.

Objective

with respect to the complexity of mandibular incisors treatment and high prevalence of the second canal, and the possibility of the relationship between the crown size and the extra canal in these teeth, the aim of this study was to determine the relationship between crown size and root canal morphology in mandibular incisors with CBCT.

Methods

In this cross-sectional study, mandibular permanent incisors were randomly collected in Qazvin City, Iran, and were mounted in eight ternary groups on a plastic slot, using putty molding material. After preparation of Scot view, the samples were scanned by CBCT NewTom 5G. Afterward, the mesiodistal and buccolingual dimensions were measured by the software’s measurement tool with a precision within tenths of a millimeter. In the next stage, a multi-planar option and 400% magnification tool of the software were utilized to study axial and cross sectional views of each tooth to determine canal type. Data were analyzed employing one-sample Kolmogorov-Smirnov, Levene, independent- samples t-test and Roc curve by SPSS version 20.

Results

The majority of mandibular incisors have a single canal (63.9% of them had type I canal system). In addition, 36.1% of the roots had two canals, among which, type III was the most common. The mean of maximum mesiodistal and buccolingual diameters in type III was significantly bigger than that in type I (p<0.05), but the means of crown size in the two canal types were not significantly different.

Conclusion

Despite increase in mesiodistal and buccolingual dimension in two canal mandibular incisors with type III canal system, their crown sizes (M-D/F-L index) were not significantly different, in comparison to single canal incisors.

Evaluation of the effect of tooth type and canal configuration on crown size in mandibular premolars by cone-beam computed tomography

INTRODUCTION

To achieve success in treatment, one cannot ignore the knowledge of pulp anatomy. Mandibular premolars are considered to be the most difficult teeth for endodontic therapy due to high variability in their canal morphology. It is possible that a relation exists between the crown size and the number of extra canals in these teeth, so this in vitro study aims to investigate the relationship between the crown size and the uncommon morphology of mandibular premolars using Cone-Beam Computed Tomography (CBCT).

MATERIALS AND METHODS

Eighty three extracted mandibular human premolars were exposed to radiation using the CBCT device. Root canal configuration was categorized according to the Vertucci's classification. The crown size was measured in three axial, coronal and sagittal sections. Finally, the relation between these two factors was evaluated with variance analysis (two-way ANOVA) and chi-square.

RESULTS

The most common canal type in the mandibular first and second premolars are type I (71% and 76%, respectively), followed by type V (29% and 22%, respectively). No significant relationship was found between the crown size and extra canals in mandibular premolars (P>0.05).

CONCLUSION

In this in vitro study, the average crown size in two-canalled second premolars was less than that in first premolars with a single canal; although the difference was not statistically significant. The research hypothesis was therefore rejected in both first and second mandibular premolars.

Mental health and well-being in different levels of perceived discrimination

BACKGROUND

To compare mental health and well-being in different levels of the perceived discrimination among Iranian people living in Tehran.

METHOD

Using multi-stage sampling, 1255 subjects with the average age of 45 years and 9 months (including 672 women and 583 men) were selected and they completed all items of the general health questionnaire (GHQ), the social well-being inventory (SWI), personal well-being inventory (PWI), and a question to assess the perceived discrimination.

RESULTS

Data analysis by Kruskal-Wallis test revealed that there were significant differences between physical symptoms (χ(2)=5.93, P<0.05) and depression (χ (2)=15.70, P<0.05), the subscales of mental health in different levels of the perceived discrimination. Furthermore, comparing personal well-being scores and its subscales in different levels of the perceived discrimination showed significant differences in personal hygiene (χ(2)=7.20, P<0.05), and security in future (χ(2)=7.60, P<0.05). Emotional well-being (χ(2)=12.25, P<0.05), self-rule (χ(2)=7.45, P<0.05), personal growth (χ(2)=19.87, P<0.05), and psychological well-being (χ(2)= 9.09, P<0.05) were significantly different in different levels of the perceived discrimination, too. Moreover, comparing social well-being in different levels of the perceived discrimination indicated significant differences between social acceptance (χ (2)=14.91, P<0.05), and social participation (χ (2)= 10.91, P<0.05).

CONCLUSION

Therefore, people are more active in society, increases the possibility of encountering with discrimination and consequently the perception of that.

Fracture strength of mesiobuccal roots following canal preparation with hand and rotary instrumentation: an in vitro study

INTRODUCTION

The aim of this in vitro study was to compare the effect of hand and rotary instruments on fracture strength of tooth roots.

MATERIALS AND METHODS

Thirty two teeth were randomly divided into two experimental groups of 15 each and one negative control group with two samples. In group 1, step-back technique with conventional stainless steel K-files was used, and in group 2, instrumentation was performed using rotary Ni-Ti Hero642. Samples in control group did not receive cleaning or shaping after access cavity preparation. After obturating each canal, tip of the spreader was locked within canal. The required force for root fracture was measured using Instron testing machine. Recorded data was statistically analyzed using t-test.

RESULTS

The mean and standard deviation force required for vertical root fracture were 50.33±19.1 and 63.1±25.46 N for hand and rotary groups respectively. However, no significant difference was found between experimental groups.

CONCLUSION

The results indicate that the manual technique did not lower fracture strength of obturated roots in comparison with the rotary preparation technique.