TiAl alloys are lightweight, show decent corrosion resistance and have good mechanical properties at elevated temperatures, making them appealing for high-temperature applications. However, polysynthetic twinned TiAl single crystals fabricated by crystal-seeding methods face substantial challenges, and their service temperatures cannot be raised further. Here we report that Ti-45Al-8Nb single crystals with controlled lamellar orientations can be fabricated by directional solidification without the use of complex seeding methods. Samples with 0° lamellar orientation exhibit an average room temperature tensile ductility of 6.9% and a yield strength of 708 MPa, with a failure strength of 978 MPa due to the formation of extensive nanotwins during plastic deformation. At 900 °C yield strength remains high at 637 MPa, with 8.1% ductility and superior creep resistance. Thus, this TiAl single-crystal alloy could provide expanded opportunities for higher-temperature applications, such as in aeronautics and aerospace.

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By removing a part of the structure, the tooth preparation provides restorative space, bonding surface, and finish line for various restorations on abutment. Preparation technique plays critical role in achieving the optimal result of tooth preparation. With successful application of microscope in endodontics for >30 years, there is a full expectation of microscopic dentistry. However, as relatively little progress has been made in the application of microscopic dentistry in prosthodontics, the following assumptions have been proposed: Is it suitable to choose the tooth preparation technique under the naked eye in the microscopic vision? Is there a more accurate preparation technology intended for the microscope? To obtain long-term stable therapeutic effects, is it much easier to achieve maximum tooth preservation and retinal protection and maintain periodontal tissue and oral function health under microscopic vision? Whether the microscopic prosthodontics is a gimmick or a breakthrough in obtaining an ideal tooth preparation should be resolved in microscopic tooth preparation. This article attempts to illustrate the concept, core elements, and indications of microscopic minimally invasive tooth preparation, physiological basis of dental pulp, periodontium and functions involved in tool preparation, position ergonomics and visual basis for dentists, comparison of tooth preparation by naked eyes and a microscope, and comparison of different designs of microscopic minimally invasive tooth preparation techniques. Furthermore, a clinical protocol for microscopic minimally invasive tooth preparation based on target restorative space guide plate has been put forward and new insights on the quantity and shape of microscopic minimally invasive tooth preparation has been provided.

The virtual patient, a unique computer simulation of the patient's face, teeth, oral mucosa, and bone, provides an extraordinary mechanism for digital dental implant surgery planning and prosthetic design. However, the seamless registration of digital scans with functional information in the context of a virtual articulator remains a challenge. This report describes the treatment of a 47‐year‐old male with full‐mouth guided immediate implant placement and immediate loading of CAD/CAM interim prostheses. Utilizing a novel digital workflow, a multifactorial registration of the vertical dimension of occlusion, centric occlusion, and facebow record were completed digitally and paired within a digital articulator. Utilizing this innovative approach, a complex treatment plan and procedure was executed smoothly with a successful prosthetic outcome demonstrating good fit, occlusion, esthetics, and patient reported satisfaction.

Objective To compare the accuracy of computer‐guided surgery and freehand surgery on flapless immediate implant placement (IIP) in the anterior maxilla. Material and Methods In this split‐mouth design, 24 maxillary incisors in eight human cadaver heads were randomly divided into two groups: computer‐guided surgery (n = 12) and freehand surgery (n = 12). Preoperatively, cone‐beam computed tomography (CBCT) scans were acquired, and all implants were planned with a software (Blue Sky Plan3). Then, two types of surgeries were performed. To assess any differences in position, the postoperative CBCT was subsequently matched with the preoperative planning. For all the implants, the angular, global, depth, bucco‐lingual, and mesio‐distal deviations between the virtual and actual implant positions were measured. Results A significant lower mean angular deviation (3.11 ± 1.55°, range: 0.66–4.95, p = 0.002) and the global deviation at both coronal (0.85 ± 0.38 mm, range: 0.42–1.51, p = 0.004) and apical levels (0.93 ± 0.34 mm, range: 0.64–1.72, p < 0.001) were observed in the guided group when compared to the freehand group (6.78 ± 3.31°, range: 3.08–14.98; 1.43 ± 0.49 mm, range: 0.65–2.31, and 2.2 ± 0.79 mm, range: 1.01–4.02). However, the accuracy of these two approaches was similar for the depth (p = 0.366). In the buccal direction, the mean deviations of both groups showed a general tendency of implants to be positioned facially, occurring more in implants of the freehand group. Conclusion In flapless IIP, computer‐guided surgery showed superior accuracy than freehand surgery in transferring the implant position from the planning. However, even with the help of a guide, the final fixture position tends to shift toward a facial direction.