Bioactivity of Calcium Silicate-Based Endodontic Materials: A Comparative in vitro Evaluation.

Background: Bioactivity refers to the ability of a material to interact with living organisms or biological systems in a way that elicits a specific response. In the context of materials science and medicine, bioactivity is particularly important because it can determine the suitability of material for various applications. Objective: To evaluate and compare different commercially available calcium silicate-based materials regarding: 1. Morphological and elemental analysis at the dentin/material interface. 2. Calcium and silicon release and uptake by adjacent root canal dentine by evaluating the calcium and silicon incorporation depth in adjacent root canal dentin. Materials and Methods: This study examined four calcium silicate-based cements: Biodentine, MTA Angelus, BioAggregate, and MTA Plus. One hundred extracted human teeth with intact apices and no cavities were selected. Root sections measuring 3 mm in length were created at the mid-root level using low-speed diamond discs. Bioactivity was evaluated at 1, 7, 30, and 90 days, respectively. Results: The principal composition of the interfacial dentine layer and incorporation of calcium and silicon into dentine was measured at 1, 7, 30, and 90 days. Statistical analysis was performed by multiple comparisons using post hoc Tukey HSD. Conclusion: All the materials have shown bioactivity, i.e. release of calcium, silicon, and their uptake in the adjacent dentin in the presence of phosphate-buffered saline.

Trained neural networking framework based skin cancer diagnosis and categorization using grey wolf optimization.

Skin Cancer is caused due to the mutational differences in epidermis hormones and patch appearances. Many studies are focused on the design and development of effective approaches in diagnosis and categorization of skin cancer. The decisions are made on independent training dataset under limited editions and scenarios. In this research, the kaggle based datasets are optimized and categorized into a labeled data array towards indexing using Federated learning (FL). The technique is developed on grey wolf optimization algorithm to assure the dataset attribute dependencies are extracted and dimensional mapping is processed. The threshold value validation of the dimensional mapping datasets is effectively optimized and trained under the neural networking framework further expanded via federated learning standards. The technique has demonstrated 95.82% accuracy under GWO technique and 94.9% on inter-combination of Trained Neural Networking (TNN) framework and Recessive Learning (RL) in accuracy.

Shear Bond Strength of Repaired Composites Using Surface Treatments and Repair Materials: An In vitro Study.

BACKGROUND: Enhancement of bond strength between new and old composite usually requires increased surface roughness of old composite to promote mechanical interlocking and subsequent coating with bonding agents to improve surface wetting and chemical bonding. So this study was carried out to evaluate and compare the effects of different surface treatments and repair materials on the shear bond strength (SBS) of composite repairs The mode of failure of repaired composites whether cohesive or adhesive was also evaluated. MATERIALS AND METHODS: The substrates for 60 composite specimens were fabricated and aged with water treatment and subjected to various surface treatments. The surface treatment regimens used in the study were: No surface treatment, abraded with diamond bur, air abraded (sandblasted) with 50 µ aluminum oxide particles. Specimens were then repaired with fresh composite using either Clearfil(™) repair or all-bond two adhesive systems. Specimens were water stored, thermocycled and tested for SBS using universal testing machine. Fractured specimens were then examined under stereomicroscope to determine the mode of failure. RESULTS: It was clearly showed that surface roughening of the aged composite substrate with air abrasion, followed by the application of Clearfil(™) repair adhesive system (Group IIIa) yielded the highest repair bond strength (32.3 ± 2.2 MPa). CONCLUSION: Surface treatment with air abrasion followed by bonding with Clearfil(™) repair adhesive system can be attempted clinically for the repair of composite restorations.

Snail and Slug are major determinants of ovarian cancer invasiveness at the transcription level.

OBJECTIVES: The transcriptional factors Snail and Slug have been reported to be important in cell migration during development and also during tumor metastasis. Their expression and role in ovarian cancer, hitherto unexplored, was examined to understand the molecular events in ovarian cancer metastases since the latter is responsible for the high degree of mortality associated with the disease. METHODS: Ectopic expression of mSnail and mSlug in the epithelial ovarian cancer cell line SKOV3 was carried out and stable clones were selected. These were used to examine specific repression of the adherens, tight and desmosomal junction components by the two transcription factors. Furthermore, functional implications with respect to enhanced migration of cells, tumorigenecity and metastasis were also studied. RESULTS: The ectopic expression of Snail or Slug resulted in epithelial-mesenchymal transition (EMT), enhanced motility, invasiveness and tumorigenecity in the cell line SKOV3. In addressing the mechanism by which Snail and Slug lead to loss of intercellular adhesion, specific repression of adherens junction components (E-cadherin and betacatenin), tight junction components (Occludin and ZO-1) and desmosomal junction components (Dsg2) were observed. Snail suppresses expression of adherens and tight junction components, while Slug suppresses expression of all the three junction components; concertedly, bringing down the intercellular adhesion between cells. Further activation of these transcriptional factors in hypoxic conditions revealed a rapid upregulation of Slug expression as an immediate reaction that probably triggers off a signaling cascade leading to Snail expression. CONCLUSIONS: These results indicate distinct roles of the transcriptional factors Snail and Slug during ovarian cancer metastasis and cell survival through mediation of EMT.