Quantum mechanical analysis of yttrium-stabilized zirconia and alumina: implications for mechanical performance of esthetic crowns

BACKGROUND

Yttrium-stabilized zirconia (YSZ) and alumina are the most commonly used dental esthetic crown materials. This study aimed to provide detailed information on the comparison between yttrium-stabilized zirconia (YSZ) and alumina, the two materials most often used for esthetic crowns in dentistry.

METHODOLOGY

The ground-state energy of the materials was calculated using the Cambridge Serial Total Energy Package (CASTEP) code, which employs a first-principles method based on density functional theory (DFT). The electronic exchange-correlation energy was evaluated using the generalized gradient approximation (GGA) within the Perdew (Burke) Ernzerhof scheme.

RESULTS

Optimization of the geometries and investigation of the optical properties, dynamic stability, band structures, refractive indices, and mechanical properties of these materials contribute to a holistic understanding of these materials. Geometric optimization of YSZ provides important insights into its dynamic stability based on observations of its crystal structure and polyhedral geometry, which show stable configurations. Alumina exhibits a distinctive charge, kinetic, and potential (CKP) geometry, which contributes to its interesting structural framework and molecular-level stability. The optical properties of alumina were evaluated using pseudo-atomic computations, demonstrating its responsiveness to external stimuli. The refractive indices, reflectance, and dielectric functions indicate that the transmission of light by alumina depends on numerous factors that are essential for the optical performance of alumina as a material for esthetic crowns. The band structures of both the materials were explored, and the band gap of alumina was determined to be 5.853 eV. In addition, the band structure describes electronic transitions that influence the conductivity and optical properties of a material. The stability of alumina can be deduced from its bandgap, an essential property that determines its use as a dental material. Refractive indices are vital optical properties of esthetic crown materials. Therefore, the ability to understand their refractive-index graphs explains their transparency and color distortion through how the material responds to light..The regulated absorption characteristics exhibited by YSZ render it a highly attractive option for the development of esthetic crowns, as it guarantees minimal color distortion.

CONCLUSION

The acceptability of materials for esthetic crowns is strongly determined by mechanical properties such as elastic stiffness constants, Young's modulus, and shear modulus. YSZ is a highly durable material for dental applications, owing to its superior mechanical strength.

Evaluation of the effect of chemical disinfection and ultraviolet disinfection on the dimensional stability of polyether impression material: an in-vitro study

BACKGROUND

Various methods, chemical and physical, disinfect dental impressions. Common chemicals include 1% Sodium Hypochlorite and 2% glutaraldehyde, while UV radiation is a prevalent physical method. Few studies compare their effects on dimensional stability in polyether impressions. This study aims to assess such stability using different disinfection methods. Therefore, this study was planned to evaluate the dimensional stability of polyether impression material using different disinfection methods.

METHODS

This in vitro study compared the effects of chemical disinfectants (1% Sodium Hypochlorite and 2% glutaraldehyde) and UV irradiation on the dimensional stability of polyether impression material. Groups A, B, C, and D, each with ten samples (N = 10), were studied. Group A was untreated (control). Group B was treated with 2% glutaraldehyde for 20 min, Group C with 1% Sodium Hypochlorite for 20 min, and Group D with UV rays for 20 min. A pilot milling machine drill was used to make four parallel holes labeled A, B, C, and D in the anterior and premolar regions from right to left. After sequential drilling, four implant analogs were positioned using a surveyor for accuracy. Ten open-tray polyether impressions were made and treated as described in the groups, followed by pouring the corresponding casts. Distortion values for each disinfection method were measured using a coordinate measuring machine capable of recording on the X- and Y-axes.

RESULTS

A comprehensive analysis was conducted using the one-way ANOVA test for distinct groups labeled A, B, C, and D, revealing significant differences in the mean distances for X1, X2, X4, X5, and X6 among the groups, with p-values ranging from 0.001 to 0.000. However, no significant differences were observed in X3. Notably, mean distances for the Y variables exhibited substantial differences among the groups, emphasizing parameter variations, with p-values ranging from 0.000 to 0.033. The results compared the four groups using the one-way ANOVA test, revealing statistically significant distance differences for most X and Y variables, except for X3 and Y4. Similarly, post-hoc Tukey's tests provided specific pairwise comparisons, underlining the distinctions between group C and the others in the mean and deviation distances for various variables on both the X- and Y-axes.

CONCLUSIONS

This study found that disinfection with 1% sodium hypochlorite or UV rays for 20 min maintained dimensional stability in polyether impressions.

Finite element analysis of stress distribution on residual root structure in socket shield procedure following immediate dental implant placement: an in vitro study

BACKGROUND

The success of implants in the socket shield technique relies on stress experienced by root fragments within the socket. Although there is no consensus on optimal root fragment thickness, varying thicknesses and dynamic implant placement induce stress in various directions and degrees. This study aimed to assess biomechanical response and stress distribution across different root fragment thicknesses in the socket shield procedure.

METHODS

This in vitro study was conducted to assess and compare the stress distribution on residual root structures of varying thicknesses positioned within the labial aspect of the maxillary incisor socket during immediate implant placement of standard dimensions. The procedure involved applying an insertional torque of 40 Ncm, and the analysis was conducted using finite element analysis software.

RESULTS

Utilizing the Numerical Technique with Abaqus software for explicit dynamics, von Mises stress and principal strain were analyzed on the root structure and bone under nonlinear contact conditions during implant torque application. For Model A, a loading torque of 40 Ncm was applied vertically on the implant, along with a horizontal force of 20 N on the root structure and bone. Results indicated maximum stress of 12.68 MPa on the root structure with a thickness of 0.5 mm and 5.61 MPa on the bone, with principal strains of 6.82E-03 and 4.10E-03, respectively. In Model B, with a root structure thickness of 1.0 mm, the maximum stress increased to 19.70 MPa, while the bone stress rose to 9.51 MPa, with principal strains of 1.03E-02 and 6.09E-03. Model C, with a root structure thickness of 1.5 mm, exhibited a maximum stress of 21.58 MPa on the root and 10.12 MPa on the bone, with principal strains of 1.16E-02 and 6.10E-03. Lastly, in Model D, with a root structure thickness of 2.0 mm, the maximum stress on the root structure and bone escalated to 28.74 MPa and 11.38 MPa, respectively, with principal strains of 1.55E-02 and 8.31E-03.

CONCLUSIONS

As the thickness of the shield increases (ranging from 0.5 to 2 mm) in socket shield procedures with immediate implant placement, both stress on the root fragment and bone and principal micro-strain escalate. However, employing a shield thickness within the range of 0.5 to 2 mm does not lead to any adverse stress generation on the residual root fragment. However, for enhanced safety, it is recommended to restrict the maximum diameter and extension of the root fragment to 1.5 mm when considering implant sizes and socket diameter for the socket shield technique.

The effectiveness of botulinum toxin for temporomandibular disorders: A systematic review and meta-analysis

OBJECTIVE

The current body of research on utilizing botulinum toxin (BTX) to manage temporomandibular disorders (TMDs) has not yet yielded definitive conclusions. The primary objective of this study was to determine the effectiveness of BTX in pain reduction for TMDs compared to placebo and other treatments. The secondary outcomes evaluated were adverse events, maximum mouth opening, bruxism events, and maximum occlusal force.

MATERIALS AND METHODS

A literature search was performed on PubMed, Dimension Publication, Scopus, and Google Scholar. The RoB 2 tool was used for quality assessment. The mean differences in pain scores were estimated to measure the effect of BTX on pain reduction. For adverse events, the risk ratio for the incidence of side effects was calculated.

RESULTS

Two hundred and sixty non-duplicate articles were identified; however, only 14 RCTS were included in this review. The total study population included 395 patients. The overall risk of bias showed a low to moderate quality of evidence. Results from 6 studies were reported only narratively; four studies were used for meta-analysis on pain reduction, and five were used for meta-analysis on adverse events. The control used in the meta-analysis was placebo injections. Results of the meta-analysis for pain reduction were statistically insignificant for the BTX group with mean differences at MD = -1.71 (95% CI, -2.87 to -0.5) at one month, -1.53 (95% CI, -2.80 to -0.27) at three months, and -1.33 (95% CI, -2.74 to 0.77) at six months. This showed that BTX treatment was not significantly better than placebo for a reduction in pain scores at 1, 3, and 6 months. Regarding safety, the placebo group showed a relative risk of 1.34 (95%CI, 0.48-6.78) and 1.17 (95%CI, 0.54-3.88) at 1 and 3 months respectively. However, the risks were not statistically significant. There was also no difference in the effectiveness of BTX compared to placebo and other treatments for maximum mouth opening, bruxism events, and maximum occlusal force.

CONCLUSION

BTX was not associated with better outcomes in terms of pain reduction, adverse events, maximum mouth opening, bruxism events, and maximum occlusal force. More high-quality RCTs are needed to better understand this topic.

The role of physiotherapy interventions in the management of temporomandibular joint ankylosis: a systematic review and meta-analysis : Running title: Physiotherapy in TMJ ankylosis

BACKGROUND

The main aim of this systematic review and meta-analysis was to identify peer-reviewed scholarly journal articles reporting the significance of physiotherapy interventions in managing TMJ ankylosis. In addition, this study aimed to critically appraise the existing evidence on the prevalence and clinical presentation, physiotherapy intervention approaches, efficacy of physiotherapy interventions, adverse effects, and safety of physiotherapy interventions in TMJ ankylosis management.

METHODS

An all-inclusive literature search was conducted using the PubMed, Google Scholar, and Scopus electronic databases. The researchers screened the potential articles and assessed for eligibility based on the reported inclusion and exclusion criteria. The quality evaluation tool for observational cohort and cross-sectional studies developed by the National Institutes of Health (NIH) and the Cochrane Collaboration's Risk of Bias Tool were used to assess the quality of the included studies. Researchers also comprehensively analyzed the data, reported the results, and discussed them according to the predominant themes.

RESULTS

The primary electronic database search yielded 409 articles, of which 25 were included in this review. A secondary search was conducted from citations of the included studies, yielding 74 articles, of which six were included in the study. A significantly higher prevalence of bony ankylosis than fibrous ankylosis, with an overall effect size of p < 0.00001. In addition, there were significantly more unilateral than bilateral presentations with an overall effect size of p < 0.00001. Moreover, there were 78 reported complications out of 245 subjects according to five included studies demonstrating a significant effect size with p = 0.001 following the treatment protocols.

CONCLUSION

This study highlighted the prevalence of bony ankylosis in temporomandibular joint ankylosis, emphasizing its impact on patients' well-being. On the other hand, the results show that physiotherapy is essential to optimize postoperative outcomes and minimize adverse events such as re-ankylosis. Practitioners and healthcare professionals must monitor postoperative recovery and ensure strict adherence to physiotherapy protocols for optimal outcomes.

Up regulation of serum L fucose glycoprotein as a diagnostic biomarker for dysplasia in oral sub mucous fibrosis patients

Glycoproteins, essential for cellular functions, contain monosaccharides like Levo-fucose, crucial for cell communication. Recent research highlights serum L-fucose as a potential biomarker for early detection of malignancies. Typically, serum L-fucose levels are low but rise with malignancy. This study evaluates serum L-fucose as an early biomarker in oral submucous fibrosis (OSMF) patients.

Aim

Assess serum L-fucose's diagnostic potential for dysplasia in OSMF patients.

Objectives

Determine the Association between Serum L Fucose Glycoprotein Levels and Dysplasia in OSF Patients.Evaluate the Diagnostic Accuracy of Serum L Fucose Glycoprotein as a Biomarker for OSF-Related Dysplasia.

Methodology

Over a span of two years, this study encompassed 80 subjects, aged between 18 and 60 years, who were clinically and histopathologically identified as OSMF patients, with or without dysplastic alterations. From each participant, 5 ml of blood was collected. Following centrifugation to separate the serum, the samples were analyzed to determine the levels of Levo-fucose.

Statistical analysis

Using SPSS (version 17.0), serum L-Fucose levels of the case group were compared to the control group using ANOVA. Frequencies were analyzed with the chi-square test, and Tukey's Test was used for multiple comparisons. Significance was set at p < 0.01.

Results

The analysis revealed a statistically significant disparity in the mean serum L-Fucose levels between the two groups (p < 0.01). Notably, Group II patients (those with OSMF and dysplasia) exhibited markedly elevated mean serum L-fucose levels.

Conclusion

Elevated serum L-Fucose levels were observed in OSMF patients with dysplasia. Harmful habits, especially gutkha chewing, were linked to Oral Squamous Cell Carcinoma onset. Serum L-fucose can be a reliable marker for evaluating precancerous conditions.

The flexural strength of 3D-printed provisional restorations fabricated with different resins: a systematic review and meta-analysis

BACKGROUND

Three-dimensional (3D) printing technology has revolutionized dentistry, particularly in fabricating provisional restorations. This systematic review and meta-analysis aimed to thoroughly evaluate the flexural strength of provisional restorations produced using 3D printing while considering the impact of different resin materials.

METHODS

A systematic search was conducted across major databases (ScienceDirect, PubMed, Web of Sciences, Google Scholar, and Scopus) to identify relevant studies published to date. The inclusion criteria included studies evaluating the flexural strength of 3D-printed provisional restorations using different resins. Data extraction and quality assessment were performed using the CONSORT scale, and a meta-analysis was conducted using RevMan 5.4 to pool results.

RESULTS

Of the 1914 initially identified research articles, only 13, published between January 2016 and November 2023, were included after screening. Notably, Digital Light Processing (DLP) has emerged as the predominant 3D printing technique, while stereolithography (SLA), Fused Deposition Modeling (FDM), and mono-liquid crystal displays (LCD) have also been recognized. Various printed resins have been utilized in different techniques, including acrylic, composite resins, and methacrylate oligomer-based materials. Regarding flexural strength, polymerization played a pivotal role for resins used in 3D or conventional/milled resins, revealing significant variations in the study. For instance, SLA-3D and DLP Acrylate photopolymers displayed distinct strengths, along with DLP bisacrylic, milled PMMA, and conventional PMMA. The subsequent meta-analysis indicated a significant difference in flexure strength, with a pooled Mean Difference (MD) of - 1.25 (95% CI - 16.98 - 14.47; P < 0.00001) and a high I2 value of 99%, highlighting substantial heterogeneity among the studies.

CONCLUSIONS

This study provides a comprehensive overview of the flexural strength of 3D-printed provisional restorations fabricated using different resins. However, further research is recommended to explore additional factors influencing flexural strength and refine the recommendations for enhancing the performance of 3D-printed provisional restorations in clinical applications.

Properties of a novel composite elastomeric polymer vinyl polyether siloxane in comparison to its parent materials: a systemic review and meta-analysis

BACKGROUND

The effectiveness of newly developed elastomeric polymer hybrid siloxane (PVES), which combines the properties of polyethylene (PE) and polyvinyl siloxane (PVS) elastomers, has been a subject of interest in recent studies. This study aimed to assess the physical properties of hybrid PVES materials by analyzing existing data from recent studies on this topic.

METHODS

A systematic literature search was conducted to retrieve peer-reviewed articles published up to February 5, 2023. The population, intervention, comparison, and pertinent outcomes were specified under the PICO framework. The primary data analysis was performed in Microsoft Excel, while statistical analysis used Meta-Essentials.

RESULTS

Of the 1152 articles assessed, 14 met the inclusion criteria. The meta-analysis of the selected studies indicated that polyether (PE) and polyvinyl siloxane (PVS) were highly correlated (two-tailed p-values of 0.000 and 0.001, respectively) with the improved tensile strength of vinyl polyether siloxane (PVES) with a significantly positive effect size. Similarly, the hydrophilic characteristics of PVES were significantly improved compared to those of PE and PVS. PE was a significant contributor to the hydrophilic characteristics of PVES, with a two-tailed p-value of 0.000. The effect size was highly positive for hydrophilicity but showed high heterogeneity. It was also observed that the dimensional accuracy of PVES was comparable to those of PE and PVS, with no statistically significant differences among the three materials.

CONCLUSIONS

PVES showed promising features, with improved tensile strength and hydrophilic characteristics compared to those of PE and PVS.

Comparative analysis of different types of occlusal splints for the management of sleep bruxism: a systematic review

BACKGROUND

Sleep bruxism is a prevalent condition in dentistry practice, characterized by involuntary grinding or clenching of the teeth during sleep. Several therapies, including occlusal splints, have been used to manage sleep bruxism and temporomandibular disorders, including occlusal splints. This study aimed to compare the effectiveness of different occlusal splints in managing sleep bruxism.

METHODS

The PICO framework encompasses the characterization of the population, intervention, comparison, and pertinent outcomes. A comprehensive and systematic literature review was conducted on PubMed, Scopus, and Google Scholar to identify grey literature. The search specifically targeted scientific studies published before September 20, 2023. The Cochrane Collaboration Risk of Bias Tool assessed the accuracy of the included Randomized Control Trials (RCTs). The modified Newcastle-Ottawa Scale assessed non-randomized studies. Data were systematically extracted, synthesized, and reported thematically.

RESULTS

Out of the total of 808 articles that were evaluated, only 15 articles were found to meet the specified inclusion criteria. Adjustable splints, such as full-occlusion biofeedback splints, were more effective in reducing sleep bruxism episodes, improving patient-reported symptoms, and enhancing overall well-being. The impact of different occlusal sprints on electromyographic activity varies, and potential adverse effects should be considered individually.

CONCLUSIONS

This review provides valuable insights into the effectiveness of occlusal splints in managing sleep bruxism. The results of this study indicate that occlusal splint therapy is a viable treatment approach for sleep bruxism.

28Assessment of thermal variations in the pulpal chamber during fabrication of provisionals using two different techniques and three materials

BACKGROUND

The issue of an increase in pulpal temperature affects direct and indirect techniques, where the fabricating material will come in direct contact with the prepared teeth.

OBJECTIVE

The aim of this study was to assess the pulpal thermal variations during provisional fabrication using direct and indirect-direct techniques, with three commonly commercially available provisional fabricating materials.

METHOD

In this vitro analytical study, 120 extracted human teeth were placed in a dentulous mould and dental stone was poured, to create a working model with an embedded natural right maxillary central incisor. Recording of thermal changes in the pulp chamber during provisionalization with direct (technique 1) and indirect-direct (technique 2) using three common types of provisional crown materials. 120 provisional crowns were fabricated using polymethyl methacrylate (DPI) (Group 1), Bis-acryl composite (Protemp 4) (Group 2) and Visible-light polymerizing (VLP) Urethane Dimethacrylate (Revotek LC) (Group 3) by two techniques and recording of peak temperature changes were done. Temperature rise in the pulp chamber was recorded using a thermocouple.

RESULTS

The mean initial and final temperature of the pulp chamber recorded for Groups 1, 2 and 3 was 31.52, 32.56; 31.01, 32.34; 32.29, 34.47 for technique 1 and 29.13, 30.5; 29.29, 31.11; 30.31, 32.65 for technique 2. The mean change in temperature was higher in Group 3 compared to the other groups.

CONCLUSION

The temperature rise detected according to this study was within the safer pulpal health limits with all the investigated materials and techniques. The resin material recommended for clinical use when the direct technique is employed for the fabrication of provisional crowns is bis-acryl composite resin (Protemp-4) as it caused minimal temperature rise in the pulpal chamber.

Comparative evaluation of open tray impression technique: investigating the precision of four splinting materials in multiple implants

BACKGROUND

This study aimed to determine the relative positioning accuracy of multiple implants utilizing four distinct types of splinting materials.

METHODS

The purpose of this in-vitro study was to compare the precision of four splinting materials in an open tray impression technique in multiple implant situations. Based on the material used for splinting, four groups were made (n = 40)- Group A: Conventional Method, Group B: Prefabricated Pattern Resin Framework, Group C: Prefabricated Metal Framework, Group D: Light Cured Pattern Resin, these groups were compared with the master model. A heat-cured clear acrylic resin and a master model were constructed. A pilot milling machine drill was used to drill four parallel holes in the anterior and premolar regions, which were later labeled as A, B, C, and D positions from right to left. Then, sequential drilling was carried out, and four 3.75‑mm diameter and 13-mm long ADIN implant analogs with internal hex were placed in the acrylic model using a surveyor for proper orientation. The impression posts were then manually screwed to the implant analogs using an open tray, and they were secured to the implants using 10 mm flat head guide pins with a 15 N.cm torque. 10 Open tray polyether impressions were made, and casts were poured. Each splinting method's distortion values were measured using a coordinate measuring machine capable of recordings in the X-, Y-, and Z-axes. Comparison of mean distances for X1, X2, and X3 was made using the Kruskal-Wallis test, and Pairwise comparison was done using Post Hoc Tukey's Test.

RESULTS

The differences between the groups were significant when assessing the distances X1, X2, and X3 (p < 0.05). The comparison of deviations between the groups revealed a statistically significant difference (p < 0.05) for the deviation distance X3 but not for the deviation distances X1 and X2. For distance Y1, the difference between the groups was statistically significant (p0.05), but it was not significant for distances Y2 and Y3. A statistically significant difference was seen in the comparison between the groups (p < 0.05) for the deviation distances Y1, Y2, and Y3. The results were statistically significant for the distance Z1 comparisons, namely, control vs. Group A (p = 0.012), control vs. Group B (p = 0.049), control vs. Group C (p = 0.048), and control vs. Group D (p = 0.021), and for distance Z3 comparison for control vs. Group A (p = 0.033). The results were statistically insignificant for the distance Z2 comparisons (p > 0.05).

CONCLUSIONS

All splinting materials produced master casts with measurements in close proximity to the reference model. However, prefabricated pattern resin bars splinting showed the highest accuracy among the studied techniques. The most recent splinting techniques using prefabricated metal framework and light-cure pattern resin showed similar accuracy.

MicroRNAs Function in Dental Stem Cells as a Promising Biomarker and Therapeutic Target for Dental Diseases

Undifferentiated, highly proliferative, clonogenic, and self-renewing dental stem cells have paved the way for novel approaches to mending cleft palates, rebuilding lost jawbone and periodontal tissue, and, most significantly, recreating lost teeth. New treatment techniques may be guided by a better understanding of these cells and their potential in terms of the specificity of the regenerative response. MicroRNAs have been recognized as an essential component in stem cell biology due to their role as epigenetic regulators of the processes that determine stem cell destiny. MicroRNAs have been proven to be crucial in a wide variety of molecular and biological processes, including apoptosis, cell proliferation, migration, and necrocytosis. MicroRNAs have been recognized to control protein translation, messenger RNA stability, and transcription and have been reported to play essential roles in dental stem cell biology, including the differentiation of dental stem cells, the immunological response, apoptosis, and the inflammation of the dental pulp. Because microRNAs increase dental stem cell differentiation, they may be used in regenerative medicine to either preserve the stem cell phenotype or to aid in the development of tooth tissue. The development of novel biomarkers and therapies for dental illnesses relies heavily on progress made in our knowledge of the roles played by microRNAs in regulating dental stem cells. In this article, we discuss how dental stem cells and their associated microRNAs may be used to cure dental illness.

Molecular mechanisms of long non-coding RNAs in differentiation of T Helper17 cells

T helper (Th) 17 cells are one of the most important T cell subsets in a number of autoimmune and chronic inflammatory diseases. During infections, Th17 cells appear to play an important role in the clearance of extracellular pathogens. Th17 cells, on the other hand, are engaged in inflammation and have been linked to the pathophysiology of a number of autoimmune illnesses and human inflammatory disorders. A diverse group of RNA molecules known as lncRNAs serve critical functions in gene expression regulation. They may interact with a wide range of molecules, including DNA, RNA, and proteins, and have a complex structure. LncRNAs, which have restricted or no protein-coding activity, are implicated in a number of illnesses due to their regulatory impact on a variety of biological processes such as cell proliferation, apoptosis, and differentiation. Several lncRNAs have been associated with Th7 cell development in the context of immune cell differentiation. In this article, we cover new studies on the involvement of lncRNAs in Th17 cell differentiation in a variety of disorders, including auto-immune diseases, malignancies, asthma, heart disease, and infections.

The developing role of extracellular vesicles in autoimmune diseases: special attention to mesenchymal stem cell-derived extracellular vesicles

Autoimmune diseases are complex, chronic inflammatory conditions initiated by the loss of immunological tolerance to self-antigens. Nowadays, there is no effective and useful therapy for autoimmune diseases, and the existing medications have some limitations due to their nonspecific targets and side effects. During the last few decades, it has been established that mesenchymal stem cells (MSCs) have immunomodulatory functions. It is proposed that MSCs can exert an important therapeutic effect on autoimmune disorders. In parallel with these findings, several investigations have shown that MSCs alleviate autoimmune diseases. Intriguingly, the results of studies have demonstrated that the effective roles of MSCs in autoimmune diseases do not depend on direct intercellular communication but on their ability to release a wide spectrum of paracrine mediators such as growth factors, cytokines and extracellular vehicles (EVs). EVs that range from 50 to 5,000 nm were produced by almost any cell type, and these nanoparticles participate in homeostasis and intercellular communication via the transfer of a broad range of biomolecules such as modulatory proteins, nucleic acids (DNA and RNA), lipids, cytokines, and metabolites. EVs derived from MSCs display the exact properties of MSCs and can be safer and more beneficial than their parent cells. In this review, we will discuss the features of MSCs and their EVs, EVs biogenesis, and their cargos, and then we will highlight the existing discoveries on the impacts of EVs from MSCs on autoimmune diseases such as multiple sclerosis, arthritis rheumatic, inflammatory bowel disease, Type 1 diabetes mellitus, systemic lupus erythematosus, autoimmune liver diseases, Sjögren syndrome, and osteoarthritis, suggesting a potential alternative for autoimmune conditions therapy.

Effect of chemical disinfection on the dimensional stability of polyvinyl ether siloxane impression material: a systemic review and meta-analysis

BACKGROUND AND OBJECTIVES

Polyvinyl ether siloxane (PVES) possesses ideal characteristics for making precise and accurate dental impressions. PVES dimensional stability owes to its better polymeric properties derived from its parent materials poly ethers and polyvinyl siloxanes. As recommended use of chemical disinfecting agents is getting more popular, there is a growing concern associated with the effect of disinfectants on PVES dimensional stability. This study was aimed to understand the PVES behavior when subjected to chemical disinfectants.

MATERIALS AND METHODOLOGY

The data was collected from research studies retrieved from Google Scholar, Scopus, and PubMed using MeSH terms of keywords "vinyl polyether siloxane AND Disinfection" or (Vinyl polyether siloxane OR polyvinyl siloxane ether OR PVES) AND (disinfectant OR disinfection)" without any restriction to publication date. The PRISMA (Preferred Reporting Items for Systemic Review and Meta-Analysis) directions were observed during the data collection, screening of studies, and meta-analysis. The primary data were retrieved, and batch exported from databases using Harzing's Publish or Perish software; primary analysis was performed in Microsoft Excel, while statistical analysis for effect size, two-tailed p-values, and heterogeneity among studies was performed using Meta Essentials. The effect size was calculated using Hedge's g values at the 95% confidence level using the random-effects model. Heterogeneity among studies was measured using the Cochrane Q and I².

RESULTS AND CONCLUSION

Dental impressions made from the PVES elastomeric impression materials showed no significant changes in dimensional stability. Immersion in the chemical disinfectant for 10 min was associated with clinically irrelevant changes in the dimensions of the PVES impressions. Disinfection with sodium hypochlorite was associated with clinically significant changes in dimensions, with a two-tailed p-value of 0.049. Disinfection with 2-2.5% glutaraldehyde solution was not associated with any significant dimensional variability.

Impact of Structured Training Program about Cadaver Organ Donation and Transplantation on Knowledge and Perception of Nursing Students at Public and Private Nursing Teaching Institute of Northern India - An Interventional Study

Background

"Donation gap" refers to the shortage of organ donors worldwide. The medical/nursing students and various healthcare workers have poor awareness and attitude toward organ donation.

Objective

We conducted this study to assess the current level of knowledge and perception regarding cadaver organ donation and transplantation among nursing students and to evaluate the impact of structured training interventions on their baseline knowledge and perception level.

Methods

It was a single-group pre-post interventional study done by nursing students of one government and one private nursing college.A pre-tested questionnaire was used as a study tool.

Statistical Analysis

Various statistical tests like one-way repeated measure ANOVA, Mauchly's test of sphericity, and Greenhouse-Geisser correction were used. Pairwise comparisons used Bonferroni corrections.

Results

The pre-test group had the lowest mean knowledge (50.2346, SD = 15.35188), and immediately after training group had the highest (57.3900, SD = 14.34626). After one month, knowledge decreased but was still higher than pretraining (mean = 52.3607, SD = 13.28141).

Conclusions

The positive attitude of nursing students may augment cadaver organ donation and transplantation in the future. The study has also highlighted the further training needs of the participants.

Assessment of Pattern of Oral Prosthetic Treatment and Prevalence of Oral Diseases in Edentulous Patients in North Indian Population: A Cross-sectional Study

Background:

The present study was undertaken for assessing the pattern of oral prosthetic treatment and prevalence of dental diseases in edentulous patients in North Indian population.

Materials and Methods:

A survey was carried out in North Indian population, and screening of the edentulous patients was done. Five hundred edentulous patients were enrolled. Complete oral and general examination was carried out. Pro forma was framed, and clinical details were recorded. Using mouth mirror and explorer, complete oral examination was carried out. Demographic profile was also evaluated. Prosthetic rehabilitation pattern of all the participants was also recorded.

Results:

Complete removable denture and removable partial denture were method of rehabilitation in 28% and 31% of the participants. Dental implant-supported complete denture was used in 8% of the patients, whereas dental implant-supported overdenture was used in 33% of the participants. Ulcerative lesions were present in 5% of the patients, whereas oral leukoplakia was present in 4% of the patients. Oral lichen planus and torus were present in 2% and 1% of the patients.

Conclusion:

Majority of the geriatric patients prefer having removable denture. Furthermore, due to nutritional deficiency associated with geriatric age, oral leukoplakia and ulcerative lesions are more common in them.

Assessment of Effect of Implant Angulation and Implant Number on the Dimensional Accuracy of Definitive Casts

AIM

To analyze the impact of implant angulation and implant number on the dimensional accuracy of definitive casts.

MATERIALS AND METHODS

Seven definitive casts with implant analogs placed in a triangular pattern were made from dental stone. The groups were as follows: group 1 (control group) all implant analogs perpendicular to the plane of the cast; the center implant analog (implant 2) being at 90° to the plane of the cast in all groups and implant analogs number 1 and 3 arranged in 5°, 10°, or 15° divergence from or convergence to the center implant (implant number 2). Three open-tray impressions of definitive casts were made in each group. Impressions were poured in type IV dental stone. Coordinates in the three planes were measured at the implant analog top surface and the base of the cast using a fine tip measuring stylus. The data were aligned and the angular differences between implant analog vectors from definitive and duplicate casts were calculated in degrees.

RESULTS

The impact of implant number on the dimensional accuracy of definitive casts was significant whereas for implant angulation it was nonsignificant. The correlation of angulation and the number of the implant did not show an interpretable pattern. The precision of duplicate casts (compared to definitive casts) is not affected by the combined interaction of implant number and implant angulation.

CONCLUSION

The close proximity of implant angulation toward a right-angled direction results in higher precision of implant. In the impression, there is direct picking from the impression copings which decreases the discrepancies in implant angulation on impression and master cast. The interaction of implant angulation and the number shows a noninterpretable pattern.

CLINICAL SIGNIFICANCE

Dimensionally accurate implant impressions can be made by using an open tray technique for three implants angled up to 15°.

Microbiological results of improvement in periodontal condition by administration of oral probiotics

Oral bacteria that degrade sulphur-containing amino acids (cysteine, cystine, and methionine) produce volatile sulphur compounds (VSCs = hydrogen sulphide, methyl mercaptan, and dimethyl sulphide) highly correlated with halitosis. When these bacteria are given the right environment, i.e. periodontal disease, cariogenic biofilm or food source they can grow in number very quickly and will start to convert proteins to VSC that, together with volatile fatty acids are largely responsible for oral malodor. Recently, the prevention of dental caries and periodontal diseases using various probiotics has been attempted. The purpose of this study was to investigate the effects of probiotics based on in vitro analysis, such as antibacterial activity, and to evaluate the neutralizing effect of probiotics on halitosis, the levels of VSCs were measured by gas chromatography. .

Estimation of dose contribution from 226Ra, 232Th and 40K radon exhalation rates in soil samples from Shivalik foot hills in India

The concentration of radium, thorium and potassium and radon exhalation rates in soil samples collected from Shivalik foot hills in the states of Haryana and Himachal Pradesh (India) were experimentally measured. A high-resolution gamma-ray spectroscopic system was used for the measurement of natural radioactivity ((226)Ra, (232)Th and (40)K) at Inter-University Accelerator Center, New Delhi, using a coaxial n-type high-purity germanium detector (EG&G, ORTEC, Oak Ridge, USA). The mass exhalation rates (EM) of radon in soil samples from the study area measured by 'sealed canister technique' using LR-115 type II track detectors varied from 50±1 to 143±6 mBqkg(-1) h(-1). The activity concentrations of (226)Ra, (232)Th and (40)K in various soil samples of the study area varied from 31±1.3 to 63±4.6, 53±1.8 to 78±2.6 and 472±4.8 to 630±7.0 Bq kg(-1) respectively. The results indicated some higher levels of radioactivity in Lal Dhang peak area of the hills compared with other locations under study.

Carbohydrate-deficient transferrin: an investigative biochemical marker of heavy alcohol consumption

Carbohydrate-deficient transferrin (CDT) has been identified as a potential biochemical marker of heavy alcohol consumption. Published studies to date primarily have focused on the ability of CDT levels to distinguish individuals with heavy alcohol drinking from nondrinking populations. In contrast, this study examines the utility of CDT levels in distinguishing alcohol-dependent patients who drink heavily from those who drink smaller amounts. This study also evaluates the potential relationship of CDT to severity of alcohol dependence and its gender differences. Serum was collected in 38 DSM-III-R alcohol-dependent outpatients at treatment entry (22 males, 16 females). CDT levels correlated with the extent of alcohol drinking in the month before treatment in males (r = 0.56, df = 20, p < .01), but not in females (r = 0.08, df = 14, NS). CDT levels also correlated with alcohol severity at pre-treatment in males (r = 0.53, df = 20, p < .05), but not in females (r = 0.27, df = 14, NS). Thus, elevated CDT levels may be mediated by alcohol severity, distinguishing CDT not only as a marker of heavy drinking, but also as an indicator of the severity of drinking-related biological and psychosocial dysfunction that may require further intervention.

A translocation tester set in pearl millet

Sixteen translocation stocks developed in pearl millet, Pennisetum typhoides (Burm.) S.&H. (2 n = 14) were inter-crossed and the meiotic configurations of f1's analysed. A translocation tester set comprising five translocation stocks, each involving two non-homologous chromosomes has been developed.