Postoperative sensitivity of composites using novel Bacillus subtilis nanofortified adhesives: a triple-blind study.

NANOTECHNOLOGY: is the art and science of dealing with nanoscale particles. This has transformed contemporary dental practices through myriad contributions to biomaterial science. Titanium dioxide nanoparticles procured from Bacillus subtilis, an eco-friendly and biogenic source, can significantly magnify the physiochemical attributes of dental materials. However, postoperative sensitivity is a major drawback of composite restorations. The incorporation of these nanoparticles into dental adhesives can greatly benefit clinical dentistry by resolving this issue. This trial aimed to evaluate the effectiveness of a novel titanium dioxide nanofortified adhesive on the postoperative sensitivity of composite restorations. METHODS: This triple-blind, parallel-group randomized controlled trial was conducted at the Department of Operative Dentistry and Endodontics, School of Dentistry, Islamabad, from May 15, 2023, to November 25, 2023. Participants (n = 60) with Class I and II primary carious lesions with a minimum cavity depth of 3-5 mm were randomly assigned to two groups (n = 30). After obtaining informed consent, the restorative procedure was accomplished using a minimally invasive approach and etch-and-rinse adhesive strategy. In group A, a nanofortified adhesive was used for composite restoration, whereas in group B, an adhesive without nanoparticles was used. Postoperative sensitivity was evaluated using the Visual Analog Scale (VAS) score at follow-up periods: of one day, one week, two weeks and one month. A Chi-square test was used to compare postoperative sensitivity between the two groups. The level of significance was set at p < 0.05. RESULTS: A noteworthy association was observed between sensitivity and the group variable at all four evaluation periods: after one day (p = 0.002), 1 week (p = 0.002), 2 weeks (p = 0.007) and one month. In conclusion, participants who underwent restorative intervention using titanium dioxide nanoreinforced adhesives reported a notable reduction in sensitivity at all time intervals. Hence, the occurrence and severity of postoperative sensitivity are significantly reduced using Bacillus subtilis-procured nanofortified adhesives as compared to conventional adhesives without nanoparticles. TRIAL REGISTRATION: This trial was retrospectively registered at ClinicalTrials.gov (ID: NCT06242184) on 03/02/2024. All procedures involving human participants were performed in conformance with this protocol.

Clinical Efficacy of a Novel Titania Nanoparticle-Reinforced Bonding Agent in Reducing Post-Restorative Sensitivity: A randomized clinical trial.

Objective: To evaluate the clinical efficacy of novel titania-nanoparticle reinforced bonding agent on post-restorative sensitivity in patients. Methods: This triple-blinded, randomized clinical trial included participants (n = 60) having Class- I and II cavitations with a minimum cavity depth of 3mm at Department of Operative Dentistry & Endodontics, School of Dentistry, Shaheed Zulfiqar Ali Bhutto Medical University, Islamabad from January 5, 2023, to June 20, 2023. They were randomly assigned into two groups A and B (n = 30). After informed consent, restorative intervention was accomplished using an etch-and-rinse adhesive strategy. In Group-A, titania-nanoparticle-incorporated bonding agent was used for composite restoration, while in Group-B, bonding agent without nanoparticles was used. The primary outcome was assessed using Visual Analogue Scale mean score. Participants were instructed to rate their sensitivity status at follow-ups: 24 hours, one week, and one month. Mann-Whitney U test was employed to compare sensitivity between the two groups. Results: According to results of this trial, a significant difference was observed between two groups after 24 hours (p = 0.004) and one week (p = 0.002). However, no discernible difference was observed after one month (p = 0.643). Conclusion: Post-restorative sensitivity in patients with composite restorations was reduced using titania-reinforced bonding agents as compared to bonding agents without nanoparticles. This shows that inclusion of titania nanoparticles into adhesive dentistry could be beneficial in resolving post-restorative sensitivity occurring with composite restorations.

Unravelling the complex interplay of age, comorbidities, and multimorbidities in COVID-19 disease progression: Clinical implications and future perspectives.

Introduction: The COVID-19 infection as an inflammatory disease has posed significant challenges to global public health due to multi-factor risks associated with it leading to disease severity and mortality. Understanding the effect of age and comorbidities on overall disease progression is crucial to identify highly susceptible individuals and to develop effective disease management strategies in a resource limited country like Pakistan. Methodology: A retrospective study was conducted on hospitalized COVID-19 patients to assess the prevalence of various comorbidities among different age groups and their effect on disease severity and mortality rate. Results: In this retrospective study, a cohort of 618 hospitalized COVID-19 patients was analyzed, consisting of 387 males (62.6 %) and 231 females (37.4 %). Notably, the young age group (15-24 years), had the lowest frequency of hospitalized COVID-19 patients, while no case was observed in children (≤14 years) showing a significant association (p < 0.001) of age and disease prevalence. Comorbidities were observed in 63.9 % of COVID-19 patients including hypertension (HTN), diabetes mellitus (DM), ischemic heart diseases (IHD), asthma, chronic kidney disease (CKD) and tuberculosis (TB). The most common comorbidities were HTN (42.1 %) followed by DM (33.8 %), IHD (16.5 %), asthma (11.2 %), CKD (7.9 %) and TB (1.9 %).Furthermore, the study revealed a significant association between comorbidities, age groups, and the need for non-invasive ventilation (NIV) (p < 0.001), mechanical ventilation (MV) (p < 0.001), and intensive care unit (ICU) admission (p < 0.001). Patients with specific comorbidities and those in the older age group (≥65 years) demonstrated a higher need for these interventions. However, patients without any comorbidity consistently exhibited the highest cumulative proportion of survival at each time point, indicating better overall survival outcomes. In contrast, patients with multimorbidities of DM/HTN/IHD, HTN/IHD, and DM/HTN/CKD had comparatively lower survival rates and higher mortality rates (p < 0.001). Conclusion: This research highlights the significant impact of age, comorbidities and multimorbidities on the severity and mortality of COVID-19 patients. It highlights the importance of considering these factors in tailoring effective management strategies for patients with COVID-19 or other infectious respiratory diseases.

Novel microbial synthesis of titania nanoparticles using probiotic Bacillus coagulans and its role in enhancing the microhardness of glass ionomer restorative materials.

Dental caries is a commonly occurring non-communicable disease throughout the world that might compromise the quality of any individual's life. Glass ionomer cements (GIC) are the most acceptable restorative materials due to their ease of manipulation, minimal tooth loss and least invasive strategy; however, they lack mechanical stability that has become a point of concern. Nanoparticles (NPs) are an outstanding option for modifying and enhancing the properties of dental materials. The focus of this study was to prepare novel, biocompatible titania dioxide (TiO2) NPs as a dental-restorative material using an efficient probiotic Bacillus coagulans. The prepared NPs were incorporated into glass ionomer restorative material at varying concentrations and investigated for cell viability percentage, microhardness and surface morphology. Results indicated that pure 100% anatase phase TiO2 NPs with particle size of 21.84 nm arranged in smooth, spherical agglomerates and clusters forms. These NPs depicted cell viability > 90%, thus confirming their non-cytotoxic behavior. GIC restorative materials reinforced by 5% titania (TiO2) NPs demonstrated the highest microhardness in comparison to the control group and other experimental groups of the study. Surface morphology analysis revealed a reduction in cracks in this novel dental-restorative material supporting its compatible biological nature with better hardness strength and negligible crack propagation. Overall, these results indicated that TiO2 NPs produced using a biological approach could be easily used as restorative materials in dental applications.

Update on the M-pox virus and safety measures taken against it globally.

Globally, more than 50 countries have been affected by Monkey pox virus after COVID-19 has subsided. WHO declared "public health emergency of international concern" in year 2022 because of virus affecting 60,000 people in just one month that belonged to clade-IIb. Previously, it had been transmitted by body fluids, lesions and touching items, but fresh transmission is via sexual activity among bisexuals and man to man sex (MSM). New outbreaks reported compromised health status of confirmed cases with rectal pain, bleeding, tenesmus, pus or blood in stool, vomiting, proctitis and abdominal pain, which became alarming for entire world because of complications leading to bacterial skin infections, sepsis, encephalitis, hemorrhagic disease, blindness and pneumonia eventually. This virus has been further deteriorating unstable and unsustainable economy that requires dire attention. Strict preventive measures in terms of personal hygiene, pet and livestock health care, hospital contaminant disposal, good surveillance record, pre and post exposure vaccination, waste and water management could be only possible strategies to eliminate devastatingly dangerous M-pox outbreaks in this epic.

Synthesis of TiO2 nanoparticles and demonstration of their antagonistic properties against selected dental caries promoting bacteria.

Objective: To evaluate antagonistic role of titanium oxide nanoparticles against selected dental caries promoting bacteria. Methods: This in vitro-experimental study was conducted at Pakistan Institute of Engineering and Applied Sciences (PIEAS), National Institute of Health (NIH) and School of Dentistry (SOD), Islamabad for the period of one year from February 2022 to January 2023. Modified hydrothermal heating method was used to prepare titanium oxide nanoparticles (TiO2Nps). Size, shape, phase, band gap energy, surface and elemental composition of Nps were deciphered by application of various modern techniques including x-ray diffraction spectroscopy (XRD), scanning electron microscopy (SEM), dynamic light scattering (DLS), UV-Vis diffuse reflectance spectroscopy (DRS), atomic force microscopy (AFM), energy dispersive x-ray spectroscopy (EDX). Antimicrobial action of nanoparticles was evaluated against representatives of gram-positive (mono-derm) and Gram negative bacteria (di-derm) responsible for promoting dental caries. The zones of inhibition were calculated by disc diffusion method for each bacterial strain. Results: Characterization revealed that TiO2Nps were having an average size of 54nm, showing anatase-rutile phase having spherical, with very few- irregularly shaped particles. TiO2Nps contained only pure titanium and oxygen in the EDX image but organic compounds in FTIR scan. Results of antimicrobial action indicated their potent bactericidal action against Pseudomonas aeruginosa (20mm), Escherichia coli (19mm) and Lactobacillus acidophilus (19nm) while comparatively less activity against Staphylococcus aureus (16mm).. Conclusion: TiO2Nps fabricated by modified protocol displayed an effective antimicrobial activity and can be used as an alternative to the contemporary chemotherapeutics against selected bacterial pathogens to prevent dental caries.

Correction: Mansoor et al. Effect of Currently Available Nanoparticle Synthesis Routes on Their Biocompatibility with Fibroblast Cell Lines. Molecules 2022, 27, 6972.

The authors wish to make the following correction to this paper [...].

Effect of Currently Available Nanoparticle Synthesis Routes on Their Biocompatibility with Fibroblast Cell Lines.

Nanotechnology has acquired significance in dental applications, but its safety regarding human health is still questionable due to the chemicals utilized during various synthesis procedures. Titanium nanoparticles were produced by three novel routes, including Bacillus subtilis, Cassia fistula and hydrothermal heating, and then characterized for shape, phase state, size, surface roughness, elemental composition, texture and morphology by SEM, TEM, XRD, AFM, DRS, DLS and FTIR. These novel titanium nanoparticles were tested for cytotoxicity through the MTT assay. L929 mouse fibroblast cells were used to test the cytotoxicity of the prepared titanium nanoparticles. Cell suspension of 10% DMEM with 1 × 104 cells was seeded in a 96-well plate and incubated. Titanium nanoparticles were used in a 1 mg/mL concentration. Control (water) and titanium nanoparticles stock solutions were prepared with 28 microliters of MTT dye and poured into each well, incubated at 37 °C for 2 h. Readings were recorded on day 1, day 15, day 31, day 41 and day 51. The results concluded that titanium nanoparticles produced by Bacillus subtilis remained non-cytotoxic because cell viability was >90%. Titanium nanoparticles produced by Cassia fistula revealed mild cytotoxicity on day 1, day 15 and day 31 because cell viability was 60−90%, while moderate cytotoxicity was found at day 41 and day 51, as cell viability was 30−60%. Titanium nanoparticles produced by hydrothermal heating depicted mild cytotoxicity on day 1 and day 15; moderate cytotoxicity on day 31; and severe cytotoxicity on day 41 and day 51 because cell viability was less than 30% (p < 0.001). The current study concluded that novel titanium nanoparticles prepared by Bacillus subtilis were the safest, more sustainable and most biocompatible for future restorative nano-dentistry purposes.

Medical and Dental Applications of Titania Nanoparticles: An Overview.

Currently, titanium oxide (TiO2) nanoparticles are successfully employed in human food, drugs, cosmetics, advanced medicine, and dentistry because of their non-cytotoxic, non-allergic, and bio-compatible nature when used in direct close contact with the human body. These NPs are the most versatile oxides as a result of their acceptable chemical stability, lower cost, strong oxidation properties, high refractive index, and enhanced aesthetics. These NPs are fabricated by conventional (physical and chemical) methods and the latest biological methods (biological, green, and biological derivatives), with their advantages and disadvantages in this epoch. The significance of TiO2 NPs as a medical material includes drug delivery release, cancer therapy, orthopedic implants, biosensors, instruments, and devices, whereas their significance as a dental biomaterial involves dentifrices, oral antibacterial disinfectants, whitening agents, and adhesives. In addition, TiO2 NPs play an important role in orthodontics (wires and brackets), endodontics (sealers and obturating materials), maxillofacial surgeries (implants and bone plates), prosthodontics (veneers, crowns, bridges, and acrylic resin dentures), and restorative dentistry (GIC and composites).

Synthesis and Characterization of Titanium Oxide Nanoparticles with a Novel Biogenic Process for Dental Application.

The prevalence of dental caries has been largely consonant over time despite the enhancement in dental technologies. This study aims to produce novel GIC restorative material by incorporating TiO2 nanoparticles synthesized by Bacillus subtilis for the treatment of dental caries. The TiO2 nanoparticles were prepared by inoculating a fresh culture of Bacillus subtilis into a nutrient broth for 24 h, which was then characterized by XRD, DRS, FTIR, AFM, SEM, TEM and EDX. These TiO2 nanoparticles were incorporated in GIC restorative material at different concentrations (0-10% TiO2 -GIC) and were tested for their mechanical properties in a universal testing machine. The XRD analysis revealed synthesis of anatase and rutile-phased TiO2 nanoparticles with a particle size of 70.17 nm that was further confirmed by SEM and TEM analysis. The EDX spectrum indicated prominent peaks of titanium and oxygen with no impurities in the prepared material. Treatment with 5% TiO2 -GIC proved to be most effective for the treatment of dental caries with no observable cytotoxic effect. An increase in the compressive strength of TiO2 nanoparticle-reinforced GIC was observed as the concentration of the TiO2 nanoparticles was increased up to 5%; subsequently, the compressive strength was lowered. An increase in the flexural strength was observed in GIC containing 0%, 3% and 5% TiO2 nanoparticles sequentially. Based on the results, it can be concluded that Bacillus subtilis-derived TiO2 nanoparticles have excellent potential for developing next generation of restorative materials for dental issues.

The Structural, Physical, and In Vitro Biological Performance of Freshly Mixed and Set Endodontic Sealers.

OBJECTIVE: The objective of this study was to evaluate the in vitro performance of endodontic sealers in their freshly mixed and set forms. METHODS: The commercially used endodontic sealers (AH Plus, Dia-ProSeal, GuttaFlow 2, and Pulpdent Root Canal Sealer) were investigated and the chemical structure of freshly mixed and set sealers were assessed with Fourier transform infrared spectroscopy (FTIR). The surface morphology and elemental analysis were assessed with a scanning electron microscope (SEM) equipped with energy-dispersive X-ray spectroscopy. The pH and solubility analysis were performed and the cytotoxicity was done on extracts of freshly mixed and set materials using Alamar blue assay. One way ANOVA and Post Hoc Tukey analysis was used to do multiple comparison analysis of the mean values and standard deviation results through SPSS version 20 (IBM Software, NY, USA) for pH, solubility, and cytotoxicity analysis. RESULTS: FTIR analysis revealed the structural pattern and the difference in freshly mixed and set samples was observed with the change in intensities of the peaks. The morphological pattern revealed the presence of micro/nano-particles with pores distributed throughout their structure. The sealer with the least solubility was AH Plus (0.10±0.01) followed by Dia-ProSeal (0.77±0.25), GuttaFlow 2 (1.88±0.82) and Pulpdent Root Canal Sealer (3.03±0.18). The solubility of AH plus was significantly lower (P<0.05) in comparison to GuttaFlow 2 and Pulpdent Root Canal Sealer. The highest pH (10.09±0.034) in the freshly mixed state and highest cytotoxicity in the freshly mixed (70.08±5.852) and set sealers (83.87±5.409) (P<0.05) at day 7 was observed in Dia-ProSeal. GuttaFlow 2 was the most biocompatible sealer in the set state and AH Plus was the most biocompatible sealer in the freshly mixed state at day 7. CONCLUSION: Clinically, the sealer is applied in fresh state, whereby this study signifies that which material is more biocompatible in fresh state and provides insight information to clinicians. AH Plus showed least solubility and cytocompatibility in fresh state compared to other groups.

Cytotoxicity, Morphology and Chemical Composition of Two Luting Cements: An in Vitro Study

Abstract Objective: To assess the cytotoxicity, surface morphology, elemental compositions and chemical characterization of two commonly used luting cement. Material and Methods: The two luting types of cement used were Elite Cement® and Hy-Bond Resiglass®. Freshly mixed (n=6) and set form (n=6) of each cement was placed in medium to obtain extracts. The extract from each sample was exposed to L929 mouse fibroblasts (1x104cells/well). Alamar Blue Assay assessed cell viability. Surface morphology and elemental composition were evaluated using scanning electron microscopy and energy dispersive spectroscopy. The chemical characterization was performed by Fourier Transform Infrared Spectroscopy. One-way ANOVA and post-hoc Tukey analysis were conducted to assess results. Results: Hy-Bond Resiglass® was the more cytotoxic of the two types of cement in both freshly mixed (68.10 +5.16; p<0.05) and set state (87.58 +4.86; p<0.05), compared to Elite Cement® both freshly mixed (77.01 +5.45; p<0.05) and set state (89.39 +5.66; p<0.05). Scanning electron microscopy revealed a more irregular and porous structure in Hy-Bond Resiglass® compared to Elite Cement®. Similarly, intense peaks of aluminium, tungsten and fluorine were observed in energy dispersive spectroscopy in Hy-Bond Resiglass. Conclusion: All these three elements (aluminium, tungsten and fluorine) have cytotoxic potential. The Fourier transform infrared spectroscopy revealed the presence of hydroxyethyl methacrylate in Hy-Bond Resiglass®, which has a cytotoxic potential.