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The aim of this study was to measure the thickness of bone labial and palatal to maxillary anterior teeth on cone beam computed tomographic (CBCT) images and to compare these measurements with direct clinical measurements to determine the reliability and accuracy of CBCT. Materials and Methods: Eighteen healthy subjects were randomly selected from among candidates for immediate implant placement in the anterior maxilla. After extraction, labial bone thickness was measured at 1, 4, and 8 mm from the bone crest. Palatal bone thickness was also measured at 1 and 4 mm from the bone crest. The same measurements were performed on presurgical CBCT images. The CBCT measurements were compared to the direct measurements, and their accuracy and reliability were assessed by Pearson correlation coefficients and intraclass correlation coefficients, respectively. Results: The mean width of labial bone was 0.50 ± 0.32 mm and 0.76 ± 0.37 mm for direct and CBCT measurements, respectively. Average thickness of the palatal bone was 1.16 ± 0.53 mm and 1.41 ± 0.51 mm for direct and CBCT measurements, respectively. The mean absolute error and mean relative error of CBCT measurements compared to direct measurements were 0.28 ± 0.29 mm and 0.60 ± 0.84 mm, respectively. The Pearson correlation between CBCT and direct measurements was 0.795 (P < .001) and the intraclass correlation coefficient between direct and CBCT measurements was 0.840. The correlation between the measurement series increased significantly when the measured bone was more than 1 mm thick. Conclusion: CBCT measurements of labial bone mostly overestimated bone thickness. CBCT has relatively good accuracy and reliability for measurement of labial bone thickness when the alveolar bone is thicker than 1 mm. However, most subjects have labial bone thinner than 1 mm; therefore, CBCT could result in large errors in many patients.

Because aniline is a persistent pollutant, a cost‐effective and efficient removal method is urgently needed. This study evaluates the synergistic effect of nickel doping in spinel zinc ferrite to enhance the photocatalytic performance of magnetic nanoparticles. Herein, X‐ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Brunauer–Emmett–Teller (BET), differential reflectance spectroscopy (DRS), transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM), energy‐dispersive X‐ray spectroscopy (EDX)/Map, and vibrating‐sample magnetometry (VSM) techniques were used to evaluate Ni0.25Zn0.75Fe2O4 MNPs synthesis by a sol–gel method. The produced nanoparticles have a surface area of 20.325 m2 g−1. At room temperature, the nanoparticles exhibit superparamagnetic characteristics and can be readily separated from the aqueous solution. The bandgap has been determined to be 1.83 eV using Tauc's plot. In addition, the photocatalytic activity of as‐prepared Ni0.25Zn0.75Fe2O4 MNPs for aniline degradation under visible light irradiation was examined. The photocatalytic results demonstrate that nickel‐doped zinc ferrite has high photocatalytic activity in aniline degradation. Additionally, Ni0.25Zn0.75Fe2O4 magnetic nanoparticles (MNPs) are highly magnetic in nature, which simplifies separation and repetitive reuse.

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5H-Chromeno[2,3-b]pyridine derivatives are a series of the most important compounds of chromenes with industrial, biological, and medicinal properties. These compounds are known as the privileged medicinal scaffold and can be synthesized by different methods such as multicomponent reactions (MCRs), Multicomponent coupling reactions (MCCRs), pot, atom, and step economy (PASE). In this review article, we have focused on the significant reactions for the syntheses and applications of 5H-chromeno[2,3-b] pyridines, including two-component reactions, three-component reactions, fourcomponent reactions, and multi-step reactions. This review is expected to serve as a useful conceptual overview and inspire the next generation to develop the different strategies for the preparation of 5HChromeno[2,3-b] pyridine derivatives.