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Different scaffold biomaterials are being investigated as a solution for bone loss due to disease or trauma. The aim of this study is the fabrication, characterization, and in vitro biological evaluation of a novel polycaprolactone (PCL) nanoscaffold incorporating pomegranate peel extract (PG) for bone regeneration. Using electrospinning, three groups of scaffolds were prepared: the control group PCL and two groups of PCL with PG concentrations (11 and 18 weight %). The antioxidant activity and the total phenolic content (TPC) of the fabricated nanoscaffolds were evaluated, in addition to the porosity and degradation measurement. Cultured osteoblasts derived from rabbit bone marrow mesenchymal stem cells were used for the assessment of cell proliferation and attachment on the scaffold’s surface. Scaffolds’ characterization showed uniform nanofibers (NFs) with a fiber diameter range of 149–168 nm. Meanwhile, higher antioxidant activity and TPC of the PG groups were detected. Furthermore, total porosities of 59 and 62% were determined for the PCL–PG scaffolds. An increased degradation rate and significant improvement in cell proliferation and cell attachment were revealed for the PCL–PG fabricated scaffolds. Such incorporation of natural food waste, PG, in PCL NFs offered novel PCL–PG scaffolds as a promising candidate for bone regeneration applications.

Aim: : To assess the most common microorganisms causing odontogenic infections and the most effective antibiotic against. Materials and Methods: The study was conducted on 150 patients with maxillofacial infection. The pus sample was collected, cultured (aerobically and anaerobically) and stained for morphological study of the isolates. Antibiotic sensitivity test for the isolates were performed. Results: A total of 260 microorganisms were isolated, Pure aerobes were identified in 54(36%) of cases, pure anaerobes in 8(5%), mixed aerobes and anaerobes in 79(53%) andno pathogenic organism were isolated in 9(6%). Among the entire aerobic isolates, Ciprofloxacin and Amoxicillin/clavulanic acid were the most effective drug (100%) followed by Clindamycin (90%). The leasteffective drugs were amoxicillin (85%). Among the entire anaerobic isolates, Metronidazole was the most effective drug (100%) followed by Ciprofloxacin, Amoxicillin/clavulanic acid, Clindamycin (90%) each and Cefotaxime(80%). The leasteffective drug was amoxicillin (100%). Conclusion: The most common bacteria isolated were Staphylococcus spp., Streptococcus spp., Klebsiella spp., Prevotella spp., Peptostreptococcus spp. Ciprofloxacin, Amoxicillin/clavulanic acid and Clindamycin were the most effective drugs for all isolates. The least effective drug was amoxicillin.

This study presents a comparative analysis of the tensile properties of 3D-printed polymer specimens with different standard geometry shapes. The objective is to assess the influence of printing orientation and geometry on the mechanical performance. Rectangular-shaped ASTM D3039 specimens with angles of 0°, 15°, and 90° are compared to various tensile test specimens based on ASTM and ISO standards. All specimens are fabricated using polyethylene terephthalate glycol (PETG) material through fused deposition modeling (FDM). Two printing orientations, flat and on-edge, are investigated, and tensile strength, elastic modulus, strain, and elongation at break are measured. The study examines the weak spot commonly found at the neck of the specimens and evaluates the broken areas. Additionally, a numerical analysis using the finite element method (FEM) is performed to identify stress risers’ locations in each specimen type. Experimental results show that the ASTM D3039-0° specimen printed in the on-edge orientation exhibits the highest tensile properties, while the flat orientation yields the best results in terms of the broken area. The ISO 527-2 specimens consistently display lower tensile properties, irrespective of the printing orientation. The study highlights the enhanced tensile properties achieved with the rectangular shape. Specifically, the tensile strength of ASTM D3039-0° was 17.87% and 21% higher than that of the ISO 527 geometry shape for the flat and on-edge orientations, respectively. The numerical analysis indicated that the ISO 527-2 specimen had either no or minimal stress raisers, and the higher stresses observed in the narrow section were isolated from the gripping location. The findings contribute to understanding the relationship between standard geometry shapes, printing orientation, and the resulting tensile properties of 3D-printed polymer specimens.

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Aim: This study aimed to measure the effect of color stability of tested adhesive resin cements on the final color of cemented ceramic veneers, as well as the effect of different thicknesses of ceramic veneers on their final colors. Materials and Methods: A total of twenty-four disc-shaped resin cement specimens were prepared {12 disks/type of cement; the light-cured NX3 (LC) and the dual-cured NX3 (DC)}. The samples were immersed in water and coffee solutions for 7, 14 days. Forty-eight rectangular-shaped laminate veneers samples were cut from IPS e.max CAD ceramic blocks (24 samples of 0.4mm thickness and 24 samples of 0.6mm thickness; where 12 samples of each thickness were cemented by light cured resin cement (NX3), and the other 12 samples were cemented by dual cured resin cement (NX3); 6 out of 12 samples were either immersed in coffee solution or immersed in water. The samples were cemented on a Delrin background material. All the samples were examined by a spectrophotometer (VITA Easy shade) before and after immersion in the solutions. Results: The ΔE values of dual-cured resin cement disks were higher than those of light cured types. Also, differences were found in ΔE of the final shade of ceramic veneer when cemented by light cured and dual cured resin cements. Furthermore, there were differences in ΔE of the final shade when using different ceramic laminate veneers thicknesses. Conclusions: The ΔE of the final shade of ceramic veneer was affected by the type of the resin cement used as well as the thickness of ceramic laminate veneer.

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Introduction: Dentin hypersensitivity is a widespread issue with high prevalence. Blocking the open dentinal tubules is one way to reduce dentin hypersensitivity. Aim: The current study aimed at evaluating the in vitro potential of a novel experimental dentifrice made of nano-fluoro hydroxyapatite (n-FHAP) produced from a biogenic source (cuttlefishbones) for occlusion of dentinal tubules. Material and Methods: 30 dentin discs (n = 30) were classified into 3 categories (n = 10) based on the dentifrices they utilized for brushing: 1 st category = artificial saliva (AS; control); 2 nd category = fluoride dentifrice (Sensodyne, UK); 3 rd category = experimental nano-FHAP dentifrice. Then, after brushing, discs were subjected to an acidic challenge with 6 percent wt citric acid (pH = 4.0) for 1 minute. By utilizing a SEM (scanning electron microscope) and EDX (energy-dispersive X-ray) spectroscopy before and after the citric acid challenge, the tubule occlusion was measured. Results: Group 1 (AS) SE micrographs revealed no tubule blockage. The tubules in Groups 2 and 3 were mostly blocked, according to SE micrographs. Data before and after the citric acid challenge data were statistically significant (p= 0.05) for all groups. Conclusion: In terms of tubule blockage, the findings of the new experimental dentifrice were equivalent to those of Sensodyne. Dentifrice containing FHAP nano-particles might be used to treat dentin sensitivity as an alternative.