Testing Machine Research Articles

In vitro evaluation of antimicrobial photodynamic therapy with photosensitizers and calcium hydroxide on bond strength, chemical composition, and sealing of glass-fiber posts to root dentin

Investigate the impact of antimicrobial photodynamic therapy (aPDT) using different photosensitizers (PSs) such as indocyanine green (IG), curcumin (CC), and methylene blue (MB), with or without intracanal application of calcium hydroxide (CH), on the push-out bond strength of glass-fiber posts (GFPs) to intraradicular dentin, the chemical composition of the root substrate, and the sealing of the adhesive interface across different thirds of intraradicular dentin. A total of 112 bovine teeth underwent biomechanical preparation and were divided into eight experimental groups (n = 14 each): Negative control with deionized water; positive control with deionized water + CH; IG group with indocyanine green and infrared laser; IG + CH group; CC group with curcumin and blue LED; CC + CH group; MB group with methylene blue and red laser; and MB + CH group. The push-out bond strength was measured using a universal testing machine (n = 8), and scanning electron microscopy characterized the fracture patterns. Energy dispersive spectroscopy (n = 3) analyzed the chemical composition of the dentin substrate, while fluorescence confocal microscopy (n = 3) assessed the adhesive interface sealing between the resin cement and root dentin. Data were analyzed using two-way repeated measures ANOVA and the Tukey test for push-out bond strength and chemical composition comparison, with the Kruskal-Wallis and Dunn’s tests (α = 0.05) for adhesive interface sealing. Significant bond strength differences were noted across root thirds and experimental groups (P < .05), with the IG + CH group showing the highest cervical bond strength and the IG group the lowest. Apical bond strength was highest in the CC group but lower in the NC and PC groups. Mixed failures predominated, except in the MB + CH group, where adhesive failures prevailed. Elemental composition varied among groups treated with different PSs and CH (P < .05), but interface quality, tag formation, and penetration depth showed no significant differences (P > .05). Laser-activated 500 mg/L CC combined with CH emerged as a clinically relevant option for root canal decontamination before GFPs luting. aPDT with different PSs and root canal depth influenced the push-out bond strength of GFPs and the chemical composition of root dentin. Curcumin-mediated aPDT at 500 mg/L proved effective, enhancing bond strength and sealing while maintaining consistent dentin composition across depths.

Photochemically Activated Microbubble Emulsion, Nd: Yap Laser, and Cerium Oxide Nanoparticles as Canal Disinfectants on Push-Out Bond Strength of Sealer to Root Dentin, Smear Layer, and Antibacterial Efficacy.

Effect of different root canal irrigation regimes microbubble emulsion (MBE) via riboflavin photosensitizer (RFP), cerium oxide (CeO2) nanoparticles (NPs), and Nd: YAP laser on antibacterial efficiency, microhardness (MH), smear layer (SL) removal efficacy, and push-out bond strength (PBS) of AH plus sealer to canal dentin. Sixty single-rooted teeth were selected, disinfected, and categorized into four groups based on the type of disinfection. Following disinfection, a pair of samples were randomly selected and visualized under scanning electron microscope (SEM) for SL evaluation. Three samples from each disinfection group were mounted on a Vickers MH tester for hardness testing. A brain-heart infusion (BHI) agar plate was inoculated with a single colony of Enterococcus faecalis (E. faecalis), and their survival rate was measured following different disinfecting regimes. The remaining samples were filled with gutta-percha (GP) and sectioned to evaluate PBS via universal testing machine (UTM), followed by failure analysis. Data were analyzed using analysis of variance (ANOVA) and Tukey's post hoc test. The survival rate of E. faecalis was lowest for Group 3 (0.11 CFU/mL) with the highest MH values (49.72 ± 1.02 N/mm2). The PBS was highest for Group 3 cervical (11.54 ± 0.49 MPa) and middle third (11.12 ± 0.50 MPa). SL removal efficacy was comparable in groups 3 and 4 at the coronal and middle third. The application of CeO2NPs as a canal irrigant in conjunction with EDTA resulted in enhanced bond values, demonstrating superior SL removal capabilities. This type of disinfection notably enhances the MH of canal dentin while demonstrating significant sterilization efficacy against E. faecalis.

Fracture resistance of analog and CAD-CAM long-span fixed provisional restorations: An in vitro experimental study.

This study aimed to evaluate and compare the fracture resistance of long-span fixed provisional restorations fabricated using milling, three-dimensional (3D) printing, and conventional methods. Sixty specimens were prepared, divided into four groups of 15 each, corresponding to four fabrication methods: computer-aided design and computer-aided manufacturing (CAD-CAM) milled provisional resins, 3D-printed provisional resins, 3D-printed permanent resins, and conventional bis-acryl restorations reinforced with wire. The specimens underwent a three-point bending test using a universal testing machine to measure fracture resistance, quantified as maximum force (in Newtons). Statistical analysis was performed using one-way ANOVA and Tukey's HSD post-hoc tests to compare the fracture resistance across the four groups. Significant differences in fracture resistance were observed among the materials tested (p < 0.001). Both the CAD-CAM milled and 3D-printed resins exhibited significantly higher fracture resistance than the conventional bis-acryl method. The results highlight the mechanical advantages of digital fabrication methods for long-span provisional applications in prosthodontics. These techniques may provide improved durability and reliability, addressing the mechanical demands of complex restorations.

Laser-Sintered versus Conventional Cobalt-Chromium Bars in Implant-Supported Complete Mandibular Overdentures: An In Vitro Strain Analysis Comparative Study

Abstract Objective The aim of this study was to compare the effect of laser-sintered and conventional cobalt-chromium bars on strain distribution around implants in mandibular implant-supported overdentures. Materials and Methods A three-dimensional (3D) epoxy resin model for completely edentulous mandible was used for this study. Two implants were placed in the canine region, and the 3D model was scanned by a laboratory scanner. Twelve cobalt-chromium bars were divided into two groups. Group 1 includes six bars that were designed by software and created using the laser sintering method. Group 2 includes six bars that were made using computer-aided design and computer-aided manufacturing to make a wax model, fabricated by a conventional lost wax-casting technique. Each implant was surrounded by four channels in the epoxy resin model, and four strain gauges were cemented. A universal testing machine was used to apply the load, and a strain measuring analysis was performed. Results Null hypothesis was rejected as there was significant difference in strain distribution around implants between both groups for the microstrains around the implants in bar-retained implant-supported prostheses, in both bilateral and unilateral results. Conclusion The laser sintering method showed better results in comparison with conventional methods in fabrication of bar-retained implant-supported prostheses due to less trauma to the implant and supporting structures.

Effect of Different Tapered Gutta-Percha Points on Push-Out Bond Strength of Two Root Canal Sealers

Abstract Objective The purpose of this study was to compare the push-out bond strength of root canal filling with different tapered gutta-percha points of two root canal sealers. Materials and Methods One hundred and twenty mandibular premolar teeth were prepared with a Reciproc blue file to size R50 and divided into four groups (n = 30 per group), with group 1 receiving iRoot SP with 02-tapered gutta-percha point (iRoot02), group 2 receiving iRoot SP with match-tapered gutta-percha point (iRoot50), group 3 receiving canal sealer bioactive glass (CS-BG) with 02-tapered gutta-percha point (BG02), and group 4 receiving CS-BG with match-tapered gutta-percha point (BG50). All samples were stored at 37°C and 100% humidity for 1 week. The specimens were resected at 3.5 and 5 mm from the apex, and push-out bond strength was measured using a universal testing machine. Results iRoot02 had the highest push-out bond strength and differed significantly from iRootR50. BGR50 produced the lowest push-out values and showed no difference from BG02. Conclusions The amount of iRoot SP in the root canal filling influences the material's resistance to pushing out. It will be more resistant if the ratio of iRoot SP to gutta-percha is high. When gutta-percha points with different tapers were used, the amount of CS-BG had no effect on the push-out force.

Effect of width-to-height ratio on the strength and behaviour of chromitite rock

The South African Bushveld Complex, Upper Group 2 (UG2) Reef pillar design has been based on a strength formula originally determined for quartzite. This formula was modified to cater for the weaker UG2 chromitite material. However, there is evidence that the pillars are stronger than predicted by the modified formula. In this study, UG2 chromitite samples were tested at a wide range of width-to-height ratios to determine the material behaviour and the relationship between strength and width-to-height ratio. Such test results on this material have not been published in the past. All testing was performed in a servo-controlled stiff testing machine (MTS 815) at a constant deformation rate of 0.08 mm/min. Specially prepared load spreader end-pieces were used to minimise any bending effects of the loading platens on the sample behaviour. The analysis showed a non-linear strengthening with increasing width-to-height ratio, best described using a power formula. A change in failure mode from pure shear to extension was observed at a width-to-height ratio of one, which has been documented previously for other materials. The change in fracture mode did not appear to affect the strength of the material. Further tests were conducted to determine the critical strain at which extension fractures initiate in chromitite. It was found that extension fracturing initiated at a critical strain of between − 2.2 mε and 3.0 mε, which was about 10 times the strain calculated by existing formulae. This new information has not been previously published for chromitite. An additional useful product of the work is an equation that can be utilised to evaluate the true uniaxial strength from samples prepared with a w/h ratio of one. Strain softening was observed on all samples up to a w/h ratio of eight. Samples with w/h ratios of three and higher were able to sustain high stresses for large strains, but almost all samples finally failed with complete loss of load. The final sudden loss of load is believed to be associated with radial cracks observed in these samples after failure.

Sarcasm Identification and Classification in Hindi Newspaper Headlines

Sarcasm identification in textual data is the most captivating area of research in the current research trends. It is a challenging task for humans as well as for the computer. In this paper, we have tried to identify sarcasm in the Hindi newspaper headlines of two of the most-read Hindi newspapers in India, namely Hindustan and Dainik Jagran. Initially, we collected 88,518 Hindi newspaper headlines and identified 1,945 headlines to be sarcastic, which we have considered for the present study. The headlines taken into consideration belong to the political domain and were published during some of the recent Legislative Assembly Elections of 2020, 2021 and 2022. Various machine learning and deep learning techniques have been used to develop the baseline models. It justifies the assumption that sarcastic text does not always bear a negative sentiment. It may bear a positive sentiment depending on the context. The present paper aims at the creation of a dataset consisting of 1,945 Hindi newspaper headlines, training and testing machine learning and deep learning models, namely Extra Trees Classifier, Random Forest Classifier, XGBClassifier, fasttext-stackedTCN and mBERT-stackedTCN for sarcasm identification on the dataset and comparing the results obtained by the models after the experiment. Out of all the choosen models, the Random Forest Classifier performs better with F 1 score of 92.11 before data augmentation and and 90.68 after data augmentation.

Development of cost-effective, high-performance ceramic-metallic brake pads for agricultural tractors

A cerametallic friction pad (CMDE) was developed through the Powder metallurgy route and validated through a classical SAEJ 661 standard laboratory test (Chase Testing machine) followed by the field test. The same was compared with an imported OE (CMOE) pad. In the chase test, CMDE fared poorly in fade-1 by 25% concerning the reference value but fulfilled the fade-II and recovery characteristics. From a wear viewpoint, the specific wear rate of CMDE and CMOE are marginally close. Considering the wear in the field test, CMDE has shown 11.1% more wear than CMOE, but 20% less wear in the mating part. More reduction in the surface roughness of CMDE after the field test evidenced its engagement characteristics by deforming asperities. Adhesive wear scoring marks were visible along the sliding direction of the pressure plate and the sintered friction pad. Thus, CMDE has the potential to replace CMOE in performance and cost

Magnesium ions regulate the Warburg effect to promote the differentiation of enteric neural crest cells into neurons

BackgroundUnderstanding how enteric neural crest cells (ENCCs) differentiate into neurons is crucial for neurogenesis therapy and gastrointestinal disease research. This study explores how magnesium ions regulate the glycolytic pathway to enhance ENCCs differentiation into neurons.Materials and methodsWe used polymerase chain reaction, western blot, immunofluorescence, and multielectrode array techniques to assess magnesium ions' impact on ENCCs differentiation. Non-targeted metabolomic sequencing, cellular acidification rate, oxygen consumption, and western blot analyzed sugar metabolism changes. D-glucose-13C6 isotope tracing identified key glucose flux changes. Surface plasmon resonance was used to detect the binding affinity of magnesium ions with key glycolysis genes. The elastic modulus of the hydrogel was measured using a universal testing machine, while pore size and porosity were assessed with scanning electron microscopy. Swelling ratios were determined using gravimetric analysis. In vivo, ENCCs in hydrogels were transplanted into renal capsule and subcutaneously, and magnesium ions' effects on ENCCs differentiation were evaluated.ResultsMagnesium ions increased glycolysis levels during ENCCs differentiation into neurons, along with significant upregulation of neuronal markers β-Tubulin and ubiquitin C-terminal hydrolase L1, and enhanced functional neuronal properties. D-glucose-13C6 tracing results showed increased carbon flux in the glycolytic pathway after magnesium supplementation. The binding affinity of magnesium ions with the glycolytic key enzyme 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 was found to be 1.08 μM. Inhibiting glycolysis suppressed ENCCs differentiation into neurons, emphasizing its crucial role. The double-cross-linked hydrogel gelatin methacryloyl—alginate (gelMA—ALMA), cross-linked with magnesium ions, showed promise in enhancing ENCCs differentiation in vivo without causing systemic hypermagnesemia.ConclusionMagnesium ions promote ENCCs differentiation into neurons by activating the Warburg effect. The GelMA-ALMA hydrogel serves as an effective localized magnesium delivery system, supporting neuronal differentiation in vivo.Graphical abstractMagnesium ions target PFKFB3, enhancing glucose flux towards G3P and subsequent lactate production, while also promoting ENCCs differentiation into neurons by facilitating NAD+ generation, suppressing ROS, and maintaining mitochondrial homeostasis. Mg: Mg2+, Glu: glucose, LA: lactic acid. Ref to the creation software of the picture.

Development and biomechanical evaluation of a 3D printed analogue of the human lumbar spine

BackgroundThere exists a need for validated lumbar spine models in spine biomechanics research. Although cadaveric testing is the current gold standard for spinal implant development, it poses significant issues related to reliability and repeatability due to the wide variability in cadaveric physiologies. Moreover, there are increasing ethical concerns with human dissection practices. Analogue models can act as cost saving alternatives to human tissue with better repeatability. The current study proposes a new methodology of spinal biomechanics testing using 3D printable surrogates and characterized its multi-dimensional stiffness in displacement-controlled loading scenarios.MethodsThe model consisted of L1 to S1 vertebrae, intervertebral discs (IVD), intertransverse, interspinous, anterior and posterior longitudinal ligaments. The vertebrae and the IVDs were derived from an open-source 3D MRI anatomography database, while the ligaments were modeled based on literature incorporating mounting points on the spinous and transverse processes. Stereolithography 3D printing along with a combination of stiff and soft photopolymer resins were used to manufacture the vertebrae and the soft tissues in the model. Thereafter, displacement-controlled pure moments were applied in the range of ± 15° at 0.5°/sec in all bending modes using a torsion testing machine and a custom pure bending jig. Model rotation and resisting moment under loading were recorded to quantify the rotational stiffness and hysteresis in the model.ResultsThe model reached a maximum of 5.66Nm and 3.53Nm at 15° flexion-extension, 3.84Nm and 3.93Nm at 15° right and left lateral bending, and 2.45Nm and 2.59Nm at 15° right and left axial rotation respectively. Model RMS error against ex vivo human response was estimated to be 1.57°, 1.64°, 0.82° in flexion-extension, lateral bending and axial rotation respectively. Bilateral symmetry in model stiffness was observed in lateral bending and axial rotation directions.ConclusionsThis study presents a reproducible 3D printable L1-S1 lumbar spine and validated it in all three orthogonal bending modes in the range of ± 15° against ex vivo and in silico data. The 3D printed analogue spine model described herein shows promising results, suggesting this model, with further validation, could have potential as a human cadaveric tissue substitute within the explored contexts of use.

The role of aging and various surface preparation methods in the repair of nanohybrid composites

BackgroundRepairing composite resins is a less invasive alternative to complete restoration replacement. To achieve a successful bond between the existing and newly applied composite materials, various surface preparation methods, such as sandblasting and acid etching, have been explored. The aim of the study was to evaluate the effect of different surface treatments on the repair bond strength of a universal nanohybrid composite resin restorative material before and after thermal aging, by utilizing a micro-shear bond strength (µSBS) test.MethodsFor the micro-shear bond strength test, a total of 120 cylindrical (3mmX2mm) nanohybrid resin based composite specimens were prepared. The prepared specimens were divided into three groups (n = 40/per group) based on surface treatment methods: a non-aged group, 10,000 thermal cycle aging and 50,000 thermal cycle aging. The aged and non-aged specimens were further divided into four groups according to adhesive application modes and surface pretreatment methods: 1.universal adhesive/self-etch mode, 2.aluminum oxide sandblasting + universal adhesive/self-etch mode, 3.universal adhesive/etch-and-rinse mode, 4.aluminum oxide sandblasting + universal adhesive/etch-and-rinse mode. Subsequently, 0.8mmX2mm disc shape light cure resin based composite specimens were applied with a direct placement technique on the treated surfaces of all samples for repair. µSBS test was performed using a universal testing machine at a crosshead speed of 1 mm/min. Kruskal-Wallis and Mann-Whitney tests were performed for statistical analysis.ResultsThe µSBS values of the non-aged group were higher than those of the 10,000 and 50,000 thermal cycle groups, with no significant differences within the non-aged subgroup (p > 0.05). In the aged groups, significant differences were observed between adhesive application modes and surface treatments. Specifically, the etch-and-rinse mode showed higher bond strengths than the self-etch mode after 50,000 thermal cycles (p < 0.05). Sandblasting combined with universal adhesive (self-etch mode) improved bond strength, especially in the 10,000 thermal cycle group (p < 0.05).ConclusionAging reduced the bond strength of composite resin repairs, with the etch-and-rinse mode outperforming the self-etch mode in aged specimens. Sandblasting alone did not enhance bond strength. These findings highlight the importance of considering aging and adhesive strategies to optimize repair outcomes, with further research needed on long-term durability.

Resistance of Resin-Bonded Ceramic Endocrowns of Different Intracoronal Depths.

This in-vitro study was conducted to assess the fracture resistance of resin-bonded ceramic endocrowns with different designs at varying intracoronal depths. Forty-eight (n = 48) extracted mandibular first molar teeth were randomly divided into four groups (n = 12). In the control group, the specimens remained untreated. Whereas the specimens in the test groups A, B, and C were decapitated 2 mm above the cementoenamel junction (CEJ) and endodontically treated. The test groups were prepared with a butt-joint design in a standardised manner with varying intracoronal depths. Groups A, B, and C were prepared to receive lithium disilicate endocrown with intracoronal cores at 0 mm, 2 mm, and 4 mm, respectively. Crowns were fabricated as a non-anatomical design with a thickness of 3 mm. After ceramic bonding procedures, specimens underwent thermocyclic ageing prior to the fracture resistance test. Specimens were loaded at a 15-degree angle using the Universal Testing Machine and the failure modes were observed. One-way analysis of variance (ANOVA) and Chi-square were utilised for data statistical analyses. Significant statistical results in fracture resistance tests were found in all experimental groups. The highest load was found in group B, followed by group C, and lastly group A (P 0.05). Although endocrowns with no extension had the lowest fracture resistance, they showed a favourable cohesive failure with statistically no significant difference from the control group. In bonded ceramic endocrowns, the fracture resistance is not newcessarily proportional to the intracanal depth. The intrcoronal cores of 4 mm did not show the highest fracture resistance, and their mode of failure was catastrophic compared to endocrowns with no intracoronal extensions.

Medial Meniscotibial Ligament Deficiency Increases Medial Meniscus Extrusion and Posterior Root Forces.

There is growing evidence that medial meniscotibial ligament (MTL) deficiency and medial meniscus extrusion may precede the development of some medial meniscus posterior root (MMPR) tears. However, no study has investigated the biomechanical consequences of MTL deficiency on the MMPR. (1) MTL deficiency leads to increased medial meniscus extrusion, (2) increased medial meniscus extrusion is correlated with increased compression and shear forces at the MMPR, and (3) MTL repair restores medial meniscus extrusion and MMPR forces to native levels. Controlled laboratory study. Fifteen pairs of fresh-frozen cadaveric knees were tested. Specimens were organized into 3 groups according to a balanced incomplete block design: (1) native, (2) MTL deficiency, and (3) MTL repair. For the MTL deficiency group, a 3-cm deficiency in the MTL was developed under direct arthroscopic visualization. Specimens in the MTL repair group underwent a 2-anchor repair that compressed the joint capsule to the proximal tibia. All specimens were biomechanically tested in full extension with a tensile testing machine. The specimens underwent cyclic loading for 10,000 cycles at 1 Hz and compression of 20 to 500 N, with a 500-N compressive force applied for 30 seconds after the 0th, 100th, 1000th, and 10,000th cycles. Ultrasound was used to measure medial meniscus extrusion. Shear and compressive forces at the MMPR were measured with a 3-axis sensor installed inferior to the MMPR tibial attachment. Medial meniscus extrusion was significantly increased in the MTL deficiency group compared with the native group (0th: 1.6 ± 0.1 mm vs 1.2 ± 0.1 mm, P < .05; 100th: 2.2 ± 0.2 mm vs 1.5 ± 0.2 mm, P < .05; 1000th: 2.8 ± 0.2 mm vs 1.8 ± 0.2 mm, P < .05; 10,000th: 3.5 ± 0.3 mm vs 2.1 ± 0.2 mm, P < .05). Compression root force was significantly increased in the MTL deficiency group compared with the native group at all cyclic loading points (0th: 21.7 ± 12.8 N vs 13.6 ± 2.4 N, P < .05; 100th: 18.9 ± 11.0 N vs 12.1 ± 7.5 N, P < .05; 1000th: 16.5 ± 9.9 N vs 11.2 ± 7.5 N, P < .05; 10,000th: 12.6 ± 8.6 N vs 9.0 ± 6.9 N, P < .05). Root shear force was significantly increased in the MTL deficiency group compared with the native group at the 0th (17.5 ± 2.5 N vs 13.6 ± 2.4 N, P < .001) and 100th (16.2 ± 2.6 N vs 12.1 ± 2.2 N, P < .001) cycles. Medial meniscus extrusion, root shear force, and compression root force of the MTL repair group were not significantly different from the native group for all cyclic loading points. Medial MTL deficiency led to increased medial meniscus extrusion as well as greater compression and shear forces at the MMPR compared with the intact and repaired MTL states, suggesting that MTL deficiency may predispose the MMPR to injury in a cadaveric model. MTL deficiency predisposes one to medial meniscus extrusion and MMPR tears. Subsequently, MTL repair can potentially correct medial meniscus extrusion and normalize forces at the MMPR.

Effect of Denture Base Material on The Stresses Induced on Implant Supporting Mandibular Bar - retained Over-denture

The aim of this study was to evaluate and compare the effect of heat cured acrylic resin denture base and glass fiber reinforced denture base on stresses induced on mandibular implant overdenture supporting structures by bar attachment using strain gauge analysis. Mandibular overdenture supported by a rigid interconnecting bar retained attachment connecting the two implants was constructed. According to the denture base material, mandibular overdentures were classified into Group I: Mandibular implant- supported overdenture was constructed using heat cured acrylic resin. Group II: Mandibular implant- supported overdenture was constructed using fiber reinforced acrylic resin. Two strain gauges were installed at the distal aspects of the implant to record the strain induced by anterior, unilateral and bilateral posterior loading of each overdenture using universal testing machine. Data was collected, tabulated and statistically analyzed. The result of this study showed that the highest stresses on the implant were recorded for the conventional heat cured acrylic denture base, and the difference was found to be statistically significant P&lt;0.05 for both anterior and unilateral load. Within the limitation of this in vitro study, the use of fiber reinforced acrylic resin denture base material for implant supported overdenture leads to better stress distribution to the implant supporting bar attachment.

Informatics strategies for early detection and risk mitigation in pancreatic cancer patients.

This review provides a comprehensive overview of the current landscape in pancreatic cancer (PC) screening, diagnosis, and early detection. This emphasizes the need for targeted screening in high-risk groups, particularly those with familial predispositions and genetic mutations, such as BRCA1, BRCA2, and PALB2. This review highlights the sporadic nature of most PC cases and significant risk factors, including smoking, alcohol consumption, obesity, and diabetes. Advanced imaging techniques, such as Endoscopic Ultrasound (EUS) and Contrast-Enhanced Harmonic Imaging (CEH-EUS), have been discussed for their superior sensitivity in early detection. This review also explores the potential of novel biomarkers, including those found in body fluids, such as serum, plasma, urine, and bile, as well as the emerging role of liquid biopsy technologies in analyzing circulating tumor DNA (ctDNA), circulating tumor cells (CTCs), and exosomes. AI-driven approaches, such as those employed in Project Felix and CancerSEEK, have been highlighted for their potential to enhance early detection through deep learning and biomarker discovery. This review underscores the importance of universal genetic testing and the integration of AI with traditional diagnostic methods to improve outcomes in high-risk individuals. Additionally, this review points to future directions in PC diagnostics, including next-generation imaging, molecular biomarkers, and personalized medicine, aiming to overcome current diagnostic challenges and improve survival rates. Ultimately, the review advocates the adoption of informatics and AI-driven strategies to enhance early detection, reduce morbidity, and save lives in the fight against pancreatic cancer.

Fracture resistance of endodontically treated teeth restored with CAD-CAM milled and prefabricated post-and-core systems.

To compare the effect of post-and-core material type and production technique on the fracture resistance of teeth. Sixty human maxillary central incisors were used for the study. Root canal treatments were performed, and the post cavities were created. The teeth were divided into six groups (n = 10) according to post material and production method: prefabricated glass-fiber post (PF), zirconia post (PZ), titanium post (PT), and CAD-CAM produced glass-fiber post (CF), zirconia post (CZ), titanium post (CT). All post-and-core restorations were luted with resin cement (RelyX U200). Static loading was applied on the luted metal copings using a universal testing machine to measure fracture resistance. The effect of material and production method on fracture resistance was evaluated with two-way ANOVA test. Tukey HSD test was used in post hoc analyses. Significance was evaluated at p < 0.05 level. In the CAD-CAM post-and-cores, the fracture resistance of zirconia was significantly higher (809 N) than titanium (569 N) and glass-fiber (342 N). In the prefabricated posts, the fracture resistance of zirconia was significantly higher than glass-fiber (445 N), while there was no significant difference between zirconia (605 N) and titanium (538 N) materials. Zirconia posts demonstrated the highest and CAD-CAM glass-fiber posts demonstrated the lowest fracture resistance compared to other types of post materials. Additional studies are needed to confirm if CAD-CAM glass-fiber posts may be considered an effective alternative treatment.

The Effect of Locking Head Inserts on the Biomechanical Properties of a 3.5-mm Broad Locking Compression Plate When Used in an Open Fracture-Gap Model.

To determine the effect of locking head inserts (LHI) on plate strain, stiffness, and deformation when applied to a 3.5-mm broad locking compression plate (LCP) in an open fracture-gap model. Six, 13-hole, 3.5-mm broad LCP were secured to epoxy bone models with a 10 mm central defect and 1 mm plate offset. Two peripheral locking screws were placed in each segment, with the remaining screw holes left unfilled. Three strain gauges were glued to each LCP at anticipated regions of maximum strain. Constructs underwent cyclic uniaxial loading at a rate of 20 mm/min to 400 N in three different configurations (Configuration 1: no LHI, Configuration 2: 3 LHI, Configuration 3: 9 LHI). LHI were tightened to 4 Nm of torque. A data acquisition system was used to collect implant strain during testing. Construct stiffness and deformation were recorded by the biomechanical testing machine. Maximum implant strain was recorded at the central screw hole directly over the simulated fracture gap in all configurations (Mdn 1,837.3 µε [interquartile range: 1,805.1-1,862.0]). There was no difference in implant peak-to-peak strain with addition of LHI at all three gauges (Gauge 1 [p = 0.847], Gauge 2 [p = 0.847], Gauge 3 [p = 0.311]). Similarly, peak-to-peak displacement (p = 0.069) and axial construct stiffness (p = 0.311) did not change with the addition of LHI. The addition of LHI to a 3.5-mm broad LCP construct was not shown to have an effect on plate strain, stiffness, or deformation.

Primary Dentin Conditioning with Methylene Blue Activated Photodynamic Therapy, Phytic Acid, and Er,Cr:YSGG to Resin-Modified Glass Ionomer Cement in Comparison to Conventional Polyacrylic Acid.

Aim: Impact of surface conditioner phytic acid (IP6) Er,Cr:YSGG laser (ECYL) methylene blue photodynamic therapy (MB-PDT) on the microleakage and shear bond strength (SBS) of resin-modified glass ionomer cement (RMGIC) to primary sound dentin. Material and method: Overall, 80 extracted sound primary molars were collected followed by their submergence in self-cure acrylic resin. The dentin surface was exposed and made flat and was assigned into four groups based on the surface conditioning. Group 1: polyacrylic acid (PAA), Group 2: 1% IP6, Group 3: ECYL, and Group 4: MB-PDT. RMGIC restorative material was bonded to primary dentin. Marginal leakage assessment was performed using silver nitrate. SBS and failure mode assessment were performed using a universal testing machine and stereomicroscope. Mean and standard deviations of SBS and marginal leakage were compared using analysis of variance and multiple comparisons of Tukey's post-hoc test (p < 0.05). Results: MB-PDT treated specimens displayed the highest values of marginal leakage (37.56 ± 1.25 nm) and lowest SBS (7.93 ± 1.03 MPa). However, samples in Group 2 conditioned with IP6 presented the lowest dye penetration score (11.23 ± 1.22 nm) and highest bond strength scores (11.12 ± 0.82 MPa). Conclusions: IP6 and ECYL have proved to be better alternatives in terms of low microleakage and improved SBS scores to PAA as a primary dentin surface conditioner for bonding RMGIC restoration. Conversely, MB-PDT, when employed as a dentin surface conditioner for RMGIC restorations, exhibited suboptimal results, characterized by elevated microleakage and compromised bond strength.

A study on the compressive strength of three-dimensional direct printing aligner material for specific designing of clear aligners

BackgroundThe demand for orthodontic treatment using clear aligners has been gradually increasing because of their superior esthetics compared with conventional fixed orthodontic therapy. This study aimed to evaluate and compare the compressive strength of three-dimensional direct printing aligners (3DPA) with that of conventional thermo-forming aligners (TFA) to determine their clinical applicability. In the experimental group, the 3DPA material TC-85 (TC-85 full) was used to create angular protrusions called rectangular pressure areas (RPA). A protrusion akin to the power ridge typically employed in conventional TFAs was created using glycol-modified polyethylene terephthalate (PETG; Control 1). RPA was created using the same TC-85 without filling the protrusions (TC-85 blank; Control 2). Compression cycle tests were conducted on an LTM 3 h electrodynamic testing machine (Zwick Roell, Germany), with 500 cycles and compression depths of 100, 300, 500, and 700 µm. Twenty specimens were tested for PETG, 17 for the TC-85 blank, and 19 for the TC-85 full.ResultsChanges in the compressive force were assessed based on the material and thickness. The results indicated significantly higher and broader ranges of compressive strength for specimens fabricated with the 3DPA material TC-85 compared with those fabricated using PETG. Among the TC-85 specimens, TC-85 full demonstrated the highest statistically significant compressive strength .Conclusions3DPA technology enables precise modifications in the shape and inner thickness at specific dental sites, including the creation of ridges in targeted areas, of aligners. These alterations enhance the biomechanical capability of aligners to exert selective forces necessary for desired tooth movement while reducing the number of attachments, thereby demonstrating the clinical potential of 3D-printed aligners in orthodontic treatment.

Biomechanical Comparison of Self-Compressing Screws and Cortical Screw Inserted with Lag Fashion in Canine Cadaveric Humeral Condylar Fracture Model.

This study compares the compression force of cortical screws used in lag fashion with partially threaded cannulated screws and fully threaded headless cannulated screws as fixation methods for humeral condylar fractures in dogs. Cadavers of eleven dogs weighing an average of 10.99 ± 2.51 kg (6.1-14.4 kg) were used. The humeri were subjected to simulated fracture by performing an osteotomy at the trochlea of humerus and classified into three groups: Group 1 applied a 3.0 mm cortical screw applied in a lag fashion, Group 2 applied a 3.0 mm partially threaded cannulated screw, and Group 3 applied a 3.5 mm fully threaded headless cannulated screw. The samples were then placed in a material testing machine, and a compression force was applied vertically to the lateral condyle until failure. There were statistically significant differences in failure load between the groups (p = 0.009). The maximum failure load in Group 3 was significantly higher than in Group 2 (p = 0.014), while there were no statistically significant differences between Group 1 and Group 2) or between Group 1 and Group 3. Partially threaded cannulated screws and fully threaded headless cannulated screws can be alternatives to traditional stabilization methods, offering simpler procedures and additional advantages.