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With the widespread application of digital impression techniques in prosthetic dentistry, accurate intraoral scan mounting, and virtual articulator parameters setting as per patients' anatomic structures are essential for treatment planning and restoration fabrication, especially for complex rehabilitation cases; meanwhile, marginal fit checking, occlusal adjustment, and porcelain layering of restorations are also crucial procedures in all cases in which the analog procedure to mount maxillary arches on a mechanical articulator is still required. This technique article presents an indirect digital approach that can first achieve virtual intraoral scan mounting and sagittal condylar inclination value setting of an Artex virtual articulator based on bony structures provided by a single cone beam computed tomography scan. It then facilitates the transfer of virtually mounted intraoral scans from the virtual articulator to the matched Artex mechanical articulator by relating a digitally scanned mounting plate of the Artex mechanical articulator to the virtual articulator, printing the intraoral scan and mounting plate scan assembly, and then mounting the printed casts on the mechanical articulator based on the printed mounting plate. This technique eliminates the conventional facebow transfer and protrusive bite registration procedures and offers a straightforward approach for the seamless integration of virtual environments and analog workflows into clinical practice. It aids in the design of restorations that are harmonious with the mandibular movements and reduces chairside adjustment time. [ABSTRACT FROM AUTHOR]

Skin is the outmost layer of human and sustains most of the external UVB irradiation, which possibly causes the skin photoaging. As a natural antioxidant, marine natural products have been paid more and more attention to their positive effects on photoaging. 6,6′‐bieckol is a phlorotanin isolated from Ecklonia cava, while its antiphotoaging bioactivity and mechanism have not been clear yet. This study proves that 6,6′‐bieckol enhances cells viability and decreases the level of ROS in UVB‐induced human immortalized keratinocytes (HaCaT) cells. It also resulted in significant downregulation of matrix metalloproteinases (MMPs), p‐c‐Fos, phosphorylated JNK, p38, IκB and p65. In addition, molecular docking also showed that 6,6′‐bieckol could bind to MMP‐1, MMP‐3 and MMP‐9. Finally, it was proved that 6,6′‐bieckol acts on MMPs through the MAPK/AP‐1 and NF‐κB pathways to reduce UVB‐induced oxidative stress damage in HaCaT cells. Therefore, 6,6′‐bieckol is a functional food and skin care ingredient with great potential in preventing photoaging. [ABSTRACT FROM AUTHOR]

Customized cast orientations and parameter settings of the virtual articulator according to the patient's condyles are indispensable parts of today's digital workflows in prosthodontics. This article describes a digital technique to align the intraoral scans to a virtual articulator by using a facial scanner to locate the patient's cutaneous landmarks of the arbitrary hinge axis and the reference plane, and to customize the sagittal condylar inclination of the virtual articulator through a digital protrusive interocclusal record and a dental computer‐aided design software program. It enables individual cast orientations and virtual articulator parameter settings without conventional facebow transferring and bite registration procedures and can be easily integrated with most virtual articulator systems on the market to allow clinicians and technicians to work in a complete digital workflow and facilitate customized treatment planning and dental prosthesis fabrication. [ABSTRACT FROM AUTHOR]

Objective Materials and Methods Results Conclusion To assess a newly developed intraoral scan protocol in enhancing the accuracy of complete‐arch implant impressions.Four impression approaches were applied to the same maxillary edentulous model with 6 implants: (1) intraoral scan (IOS), (2) intraoral scan with scan aid (IOS‐SA), (3) calibrated intraoral scan protocol (CISP), and (4) conventional splinted open‐tray impression (CONV). Each approach was repeated 10 times, and a direct scan of the model with a desktop scanner was used as a reference model. The alignment of scans and the reference model was conducted by two methods: (a) aligning all scan bodies to evaluate the overall fit, and (b) aligning the first and second scan bodies to simulate the Sheffield fit test for passive fitting of multiple implant‐supported prostheses. Linear deviations from the reference model (trueness) and within each group (precision) were analyzed using Python scripts.When aligned by all scan bodies, the CISP group exhibited comparable mean trueness (38.33 μm) and precision (45.97 μm) to the CONV group (44.30 and 47.92 μm respectively), both of which significantly outperformed the IOS group (86.82 and 83.17 μm, respectively). Furthermore, in the virtual Sheffield fit test, the CISP group achieved the highest levels of mean trueness at the end span (121.7 μm), making a linear deviation reduction of 36.7%, 60%, and 41.4% when compared to the CONV, the IOS, and the IOS‐SA groups, respectively. Moreover, the CISP group (104.3 μm) displayed a remarkable 65, 182, and 86 μm advantage in precision over the CONV, IOS, and IOS‐SA groups, respectively.CISP demonstrated comparable accuracy to the gold standard, the conventional splinted open‐tray impression. Furthermore, it excelled in the virtual passive fitting test. [ABSTRACT FROM AUTHOR]

Accurately mounting dental casts on an articulator is an essential step in prosthetic treatments. In digital dentistry, virtual articulator mounting procedures rely on virtual facebow records. However, virtual facebow records usually require devices like face scanners or jaw motion tracking systems that are not commonly available in most dental practices. The present technique report describes a straightforward intraoral scanner-based virtual facebow transfer approach. In this technique, a reference facebow joint support was first scanned and aligned with a virtual articulator. Then, a patient's facebow joint support and bite fork assembly were scanned chairside with an intraoral scanner and aligned with the virtual articulator by matching common features with the reference facebow joint support. After aligning the patient's intraoral scans with the patient's bite fork scan that was already superimposed on the virtual articulator, a virtual mounting process was achieved. Once the corresponding reference facebow joint supports have been generated, this technique can be easily implemented with most facebow systems and be seamlessly integrated into daily clinical practice as only an intraoral scanner and a conventional facebow were required., (© 2024 The Author(s). Journal of Prosthodontics published by Wiley Periodicals LLC on behalf of American College of Prosthodontists.)

A digital approach is described for fabricating a splinted framework and custom open tray for the impression of multiple implants based on a virtually created implant cast with the digital prediction of the future impression coping positions. In this technique, impression copings to be used in the definitive impression-making process were digitally scanned and aligned to a preliminary cast using installed protective caps of screw-retained abutments as references, which resulted in a virtual cast that offers information both about the impression coping positions and their surrounding tissues and could allow a splinted framework and custom open tray to be digitally designed and fabricated. Creation of a virtual cast through digital technologies eliminates the traditional manual splinted framework and custom tray fabrication procedures. Additionally, only one set of impression copings and analogs is needed in this technique, thereby reducing treatment time and cost. It also offers a splinted framework and custom open tray with consistent quality., (© 2023 by the American College of Prosthodontists.)