Dr Mohammed Mahmoud Youssif

The temperature-triggered gating in flexible nanoporous frameworks exhibits dynamic nanopore regulation under external stimuli, leading to optimum pore sizes and enhanced selectivity for isotopologue separation. In this work, we report one of the very rare observations of temperature-responsive gating in efficient bio-derived ‘nanoporous carbon’ material. The distinctive characteristics of this material, such as its suitable pore sizes for Kinetic Quantum Sieving (KQS) that lead to strong diffusion limitation, as well as its capacity to operate at higher temperatures, overcome the limitations of existing crystalline porous materials. It is remarkable that this activated carbon derived from biological sources, even without any strong binding sites, can release hydrogen isotopologues at a higher temperature of 180 K in comparison to MOF-74(Ni), which possesses many open metal sites but releases mostly at 90–100 K. The separation performance is also demonstrated to reach up to 120 K, and only six separation cycles are needed to enrich from a low concentration of 4 % to –92 % D2 in a mixture of deuterium (D2/H2). This finding suggests that inexpensive porous carbon’s thermal pore size modulation can significantly increase the operating temperature for precise separation of hydrogen isotopologues.

Objectives
to evaluate the clinical effectiveness of 1% dimethyl-sulfoxide (DMSO/H2O) dentin pretreatment on the clinical performance of 2-step etch-rinse adhesive after 36-months of a follow-up.

Methods
Twenty-nine patients with 82 non carious cervical lesions NCCLs were eligible for the study. NCCLs were randomly distributed into 2 equal groups. Both groups were acid etched then bonded with (Single-bond2, 3M-ESPE) and restored with a nanohybrid composite (Z350XT, 3M-ESPE) under rubber-dam isolation. Only for the intervention group 1% DMSO/H2O was applied for 60s then blot dried after etching and before bonding. The restorations were evaluated at baseline, 12-, 24-, and 36-months using FDI criteria for evaluation of the restoration. For the statistical analysis, intergroup comparison between interventions was performed using Chi-Square-test (P ≤ .05), intragroup comparison within each intervention was performed using the Cochran's Q-test (P ≤ .0083).

Results
In the current study, intergroup comparison between both groups at baseline and after 12, 24 and 36 months showed no statistically significant differences for all tested outcomes (P > .05), except for marginal discoloration at 36 months, where there was statistically significant difference (P < .05) favoring DSMO. Intragroup comparison within control revealed statistically significant deterioration through time (P < .001) for all tested parameters, also within DSMO there was statistically significant change through time (P < .0083).

Conclusion
The clinical performance of a 2-step etch-rinse adhesive in combination with 1% DMSO pretreatment was better than the control without pretreatment. Longer follow-up and higher concentrations of DMSO pretreatment should be evaluated in the future.

Clinical Significance
Several laboratory studies showed that DMSO pretreatment improves the hybrid layer quality and integrity. However, this clinical trial gave the proof of the clinical effectiveness of this protocol after 36-months follow-up.

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BACKGROUND: Sinus floor elevation is one of the predictable techniques for augmentation of vertically deficient posterior maxillary alveolar ridges. Several biomaterials were reported to be successful for sinus augmentation, including xenografts and hydroxyapatite. The aim of this study was to compare the quality and quantity of generated bone using xenografts versus nanohydroxyapatite in sinus augmentation.

METHODOLOGY: Twenty-four patients/sinuses were randomly assigned into two groups; in the control group, patients underwent sinus floor elevation and augmentation using deproteinized bovine bone (DBB), whereas in the study group, the sinus was augmented using nanohydroxy-apatite bone (NHA). For each patient, the amount of bone height was assessed preoperatively, immediately postoperatively, and 6 months postoperatively. Furthermore, the quality of the newly formed bone was assessed via histological and histomorphometric analyses after 6 months postoperatively.

RESULTS: Both biomaterials showed a good level of consolidation. In the study group, the mean bone height after 6 months was 11.72 ± 1.24 compared to 12.01 ± 1.16 mm in the control group which was not statistically significant (p > 0.05). The mean bone area percent of newly formed bone was 29.84% ± 6.7% for NHA group and 34.73 ± 7.9 for DBB group. Moreover, the mean percent of residual grafting material was 32.43% ± 11.53% for NHA group compared to 30.43% ± 8.27% for DBB group. Histologically, there was no significant difference between both groups regarding different parameters (p > 0.05).

CONCLUSION: The two-stage sinus floor augmentation using NHA and DBB revealed no statistically significant difference regarding both the quality and the quantity of the regenerated bone. Studies with larger samples and longer follow up are recommended.

TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT03184857.

AIM: The purpose of this study was to assess the accuracy of a customized deep learning model based on CNN and U-Net for detecting and segmenting the second mesiobuccal canal (MB2) of maxillary first molar teeth on cone beam computed tomography (CBCT) scans.

METHODOLOGY: CBCT scans of 37 patients were imported into 3D slicer software to crop and segment the canals of the mesiobuccal (MB) root of the maxillary first molar. The annotated data were divided into two groups: 80% for training and validation and 20% for testing. The data were used to train the AI model in 2 separate steps: a classification model based on a customized CNN and a segmentation model based on U-Net. A confusion matrix and receiver-operating characteristic (ROC) analysis were used in the statistical evaluation of the results of the classification model, whereas the Dice-coefficient (DCE) was used to express the segmentation accuracy.

RESULTS: F1 score, testing accuracy, recall and precision values were 0.93, 0.87, 1.0 and 0.87 respectively, for the cropped images of MB root of maxillary 1st molar teeth in the testing group. The testing loss was 0.4, and the area under the curve (AUC) value was 0.57. The segmentation accuracy results were satisfactory, where the DCE of training was 0.85 and DCE of testing was 0.79.

CONCLUSION: MB2 in the maxillary first molar can be precisely detected and segmented via the developed AI algorithm in CBCT images.

TRIAL REGISTRATION: Current Controlled Trial Number NCT05340140. April 22, 2022.

We studied the characteristics and survival of patients with sorafenib-treated HCC and impact of underlying etiology on outcomes. This retrospective multicenter study recruited patients with sorafenib-treated advanced HCC (12/2016 to 4/2023) till death or the study end (2/2024). Time to progression (TTP) and overall survival (OS) were recorded. We evaluated; Clinico-laboratory and imaging predictors of OS, The impact of underlying etiology on tumor variables, outcomes and tolerance for sorafenib > 6 months. This study included 706 patients. Median duration of Sorafenib therapy was 240.00 (90.00-360.00) days. Median OS was 314.00(146.00-601.00) days. Median TTP was 180.00(90.00-330.00) days. COX regression revealed that the independent factors of mortality were baseline AST, Tumor size, hepatic vein thrombosis (HVT), development of jaundice and shifting to Regorafenib. Advanced HCCs were more common on top of non-cirrhotic non-viral and HBV-related liver disease. Adverse events, TTP and tumor response didn't differ with the underlying etiology. Median OS was lower in non-viral-related HCC than HCV-related HCC (218.00 versus 326.50 days, P-value = 0.048). Patients who continued sorafenib > 6 months had lower AFP, HVT, adverse effects and better tumor response after 3 months. OS is lower in non-viral Sorafenib-treated HCC compared with viral-related HCC and Sorafenib was well-tolerated among different HCC etiologies.