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Dental anatomy education for dental technology students should be developed in alignment with digital dental laboratory practices. We hypothesized that a virtually assisted sketching‐based dental anatomy teaching module could improve students' acquisition of skills essential for digital restoration design. The second‐year dental technology curriculum included a novel virtual technology‐assisted sketching‐based module for dental anatomy education. Pre‐ and post‐course assessments evaluated students' skill sets and knowledge bases. Computer‐aided design (CAD) scores were analyzed after one year to assess how the skills students developed through this module impacted their subsequent CAD performance. Participants who undertook the dental sketching‐based teaching module demonstrated significantly improved theoretical knowledge of dental anatomy, dental aesthetic perception, and spatial reasoning skills. A partial least squares structural equation model indicated that the positive effects of this module on subsequent CAD performance were indirectly mediated by dental aesthetic perception, spatial reasoning, and practice time. A virtually assisted sketching‐based dental anatomy teaching module significantly improved students' acquisition of skills and knowledge and positively mediated dental technology students' CAD performance. [ABSTRACT FROM AUTHOR]

Background: Customized computer‐aided‐design/computer‐aided‐manufacturing (CAD/CAM) titanium meshes have been adopted for alveolar bone augmentation. But the inaccuracies between planned and created bone volume/contour are quite common, and the surgical placement of the customized mesh was considered as the first critical factor. However, the evaluation of surgical placement accuracy of customized mesh is currently lacking. Purpose: The aim of this study was to evaluate the accuracy of the surgical placement of customized meshes. Methods: A total of 30 cases, 20 without the screws‐position‐guided template and 10 with the screws‐position‐guided template, were included in this study. The cone beam CT (CBCT) data sets of pre‐ and postoperative were converted into 3D models and digitally aligned. Then the actual placement of customized mesh and retainer titanium screws was compared to the virtual one to assess the surgical placement accuracy of customized mesh. At least 6 months after surgery, a new CBCT was taken and converted into 3D models. Planned bone volume, created bone volume, vertical bone augmentation, healing complications rate, pseudo‐periosteum rate, exposure rate, and infection rate were all evaluated. Results: The 3D digital reconstruction/registration analysis showed that the average difference between actual placement and planned one of customized mesh in positive and negative directions was 2.69 ± 0.70 mm and −1.41 ± 0.90 mm, respectively, without the screws‐position‐guided template. And the mean difference values between the actual and planned placement of the screws on the X and Y axes were 0.74 ± 0.85 mm and 0.89 ± 0.84 mm. In contrast, with the screws‐position‐guided template, the results were 2.38 ± 0.69 mm and −1.30 ± 1.13 mm. Accordingly, the mean difference values of screws were 0.76 ± 0.84 mm and 0.94 ± 0.72 mm. There was no statistical difference between the two groups, and the noninferiority of the control group compared to the test group was also confirmed by the comparative analysis. Conclusion: It can be concluded that there is a certain deviation between the planned surgical placement and actual one of customized mesh, and using screws‐position‐guided template is of limited help for its accurate placement. Further research is needed to achieve precise surgical placement of the customized mesh to achieve precise alveolar bone augmentation. [ABSTRACT FROM AUTHOR]

Objective: To present the results of guided bone regeneration (GBR) with three‐dimensional printing individualized titanium mesh (3D‐PITM) applied to alveolar bone defects with different Terheyden classifications and the factors affecting the osteogenic outcome. Materials and Methods: Fifty‐nine patients, presenting with 61 defect sites, were enrolled between 2018 and 2021. GBR+3D‐PITM was obtained with simultaneous or second stage implant placement. The complication rate, the success rate of the bone grafting procedure and the survival rate of the implant were documented. Bone gain, thickness of pseudo‐periosteum and peri‐implant marginal bone loss (MBL) were measured through digital methods by imaging data (CBCT and X‐ray). Results: Out of 61 sites, 20 were exposed (exposure rate: 32.8%). The width, height, and volume bone gain at P3 (mesh removal) were 5.22 ± 3.19 mm, 5.01 ± 2.83 mm, and 588.91 ± 361.23 mm3, respectively. From P2 (3D‐PITM+GBR) to P3, changes in bone gain were not statistically different in the different Terheyden classifications, the occurrence of exposure (p <.001 for all dimensions) and the different type of pseudo‐periosteum (p =.030 for width and p =.002 for height) were significantly correlated with the reduction of bone gain. Terheyden classification of the defect sites was significantly associated with the occurrence of exposure (p =.014) and types of the pseudo‐periosteum (p =.015). Conclusion: The 3D‐PITM can be used in alveolar bone defects with different Terheyden classification, but cases with severe vertical bone defects have a greater chance of the 3D‐PITM exposure and the exposure can affect the outcome of bone augmentation. [ABSTRACT FROM AUTHOR]

Mg–Gd alloys are candidates for degradable implants combining favorable mechanical and corrosion properties. Gd has a high solid solubility in Mg and an acceptable biocompatibility. The influences of different amount of Gd additions and solid solution (T4) treatment on mechanical properties and corrosion in 0.9 wt% NaCl and cell culture medium (CCM) of magnesium are systematically investigated. The effects of Gd are clarified by microstructural characterizations as well as stress and degradation analysis. It is shown that minor Gd additions to pure Mg lead to Gd solid solution in Mg (α) and the formation of Mg5Gd intermetallic particles (IMPs), which increase the hardness, tensile, and compressive strength. The GdH2 phase is found in low‐alloyed Mg–Gd alloys. The corrosion rate (CR) is increased by the addition of more Gd due to the increased kinetics of the cathodic reaction. However, the resistance to degradation is effectively improved by T4 heat treatment due to the dissolution of IMPs. The reduced susceptibility to pitting can be achieved by a minor Gd addition and T4 heat treatment. The Mg–2Gd alloy is a potential candidate for implants due to its good combination of tailorable mechanical properties and low homogeneous in vitro degradation rate (DR). [ABSTRACT FROM AUTHOR]

Objective: To develop an in vivo model to simulate the complex internal environment of diabetic peri‐implantitis (T2DM‐PI) model for a better understanding of peri‐implantitis in type 2 diabetic patients. Materials and methods: Maxillary first molars were extracted in Sprague‐Dawley (SD) rats, and customized cone‐shaped titanium implants were installed in the extraction sites. Thereafter, implants were uncovered and customized abutments were screwed into implants. A high‐fat diet and a low‐dose injection of streptozotocin were utilized to induce T2DM. Finally, LPS was locally injected in implant sulcus to induce peri‐implantitis. Results: In the present study, T2DM‐PI model has been successfully established. Imaging analysis revealed that abundant inflammatory cells infiltrated in the soft tissue in T2DM‐PI group with concomitant excessive secretion of inflammatory cytokines. Moreover, higher expression of MMP and increased number of osteoclasts led to collagen disintegration and bone resorption in T2DM‐PI group. Conclusions: These results describe a novel rat model which stimulate T2DM‐PI in vivo, characterized by overwhelming inflammatory response and bone resorption. This model has a potential to be used for investigation of initiation, progression and interventional therapy of T2DM‐PI. [ABSTRACT FROM AUTHOR]

Aim: To investigate the feasibility of predicting dental implant loss risk with deep learning (DL) based on preoperative cone‐beam computed tomography. Materials and Methods: Six hundred and three patients who underwent implant surgery (279 high‐risk patients who did and 324 low‐risk patients who did not experience implant loss within 5 years) between January 2012 and January 2020 were enrolled. Three models, a logistic regression clinical model (CM) based on clinical features, a DL model based on radiography features, and an integrated model (IM) developed by combining CM with DL, were developed to predict the 5‐year implant loss risk. The area under the receiver operating characteristic curve (AUC) was used to evaluate the model performance. Time to implant loss was considered for both groups, and Kaplan–Meier curves were created and compared by the log‐rank test. Results: The IM exhibited the best performance in predicting implant loss risk (AUC = 0.90, 95% confidence interval [CI] 0.84–0.95), followed by the DL model (AUC = 0.87, 95% CI 0.80–0.92) and the CM (AUC = 0.72, 95% CI 0.63–0.79). Conclusions: Our study offers preliminary evidence that both the DL model and the IM performed well in predicting implant fate within 5 years and thus may greatly facilitate implant practitioners in assessing preoperative risks. [ABSTRACT FROM AUTHOR]

Previous investigations demonstrated that rare‐earth elements (REs) could improve their creep properties effectively. Herein, the influence of Y content on the creep properties of magnesium is investigated systematically with different amount of Y additions. The mechanisms responsible for creep deformation are clarified by the analysis of stress exponent and microstructural characterizations. It is found that the addition of Y in Mg can improve both the ambient strength and high temperature strength owing to its effective solid solution strengthening. At room temperature, the yield strength of Mg–Y alloys has a linear relation with the content of Y. When tested at high temperatures, the yield strength reduces. Compared with pure magnesium, Mg–Y alloys exhibit a high thermal stability even above 200 °C. Small amount of Y addition can improve the creep resistance of Mg largely. With further increasing its content, its contribution to the improvement of creep resistance is weakened for Mg. Under the applied stresses 60–100 MPa and at temperatures of 200–250 °C, the responsible creep mechanism is dislocation controlled. During creep deformation, the Y segregation regions play an important role in hindering the movement of dislocations. [ABSTRACT FROM AUTHOR]

A modified quenching and deformation dilatometer (TA instruments DIL 805A/D/T) is now in operation at the Heinz Maier‐Leibnitz Zentrum (MLZ, Germany) neutron center. It is customized for running neutron scattering measurements during the temperature/deformation treatment of the sample, in particular neutron diffraction (phase, texture, and lattice strain) and neutron small angle scattering. The bulk length change of dilatometer specimens is successfully combined with in situ neutron diffraction patterns for analyzing dynamic processes in metallic materials. A detailed introduction to the unique dilatometer is given and examples of recent experiments highlight the use of the added insight provided by combining diffraction and dilatometry. [ABSTRACT FROM AUTHOR]

Background: Few studies have focused on the dimensional accuracy of customized bone grafting by means of guided bone regeneration (GBR) with 3D‐Printed Individual Titanium Mesh (3D‐PITM). Purpose Digital technologies were applied to evaluate the dimensional accuracy of customized bone augmentation with 3D‐PITM with a two‐stage technique. Materials and methods: Sixteen patients were included in this study. The CBCT data of post‐GBR (immediate post‐GBR) and post‐implantation (immediate post‐implant placement) were 3D reconstructed and compared with the pre‐surgical planned bone augmentation. The dimensional differences were evaluated by superimposition using the Materialize 3‐matic software. Results: The superimposition analysis showed that the maximum deviations of contour between were 3.4 mm, and the average differences of the augmentation contour were 0.5 ± 0.4 and 0.6 ± 0.5 mm respectively. The planned volume of bone regeneration was approximately equal to the amount of regenerated bone present 6 to 9 months after the surgical procedure. On average, the vertical gain in bone height was about 0.5 mm less than planned. And, the horizontal bone gain on the straight buccal of the dental implants and 2 to 4 mm apical of the platform fell also about a 0.5 mm short on average. Statistically significant differences were observed between the augmented volume of virtual and post‐GBR, and the horizontal bone gain of post‐implantation on the level of 4 mm apical to the implant platform (P <.05). Conclusions: The dimensional accuracy of customized bone augmentation with the 3D‐PITM approach needs further improvement and compared to other surgical approaches of bone augmentation. [ABSTRACT FROM AUTHOR]

Background: Limited studies focused on the bone profile maintenance at the alveolar ridge crest applying horizontal bone augmentation. Purpose A novel approach named as "in‐situ bone ring technique" was introduced to be compared with tent‐pole technique to evaluate their horizontal bone gain, resorption, and postoperative perception. Materials and methods: A total of 30 patients were included in this retrospective cohort study. All patients required horizontal bone augmentation at anterior site. Accordingly, quantitative and qualitative analyses were conduct radiographically and histologically between in‐situ bone ring (ring group) and tent‐pole technique (tent group). Moreover, the visual analog scale (VAS) was introduced to assess the patients' perception toward both treatments. Results: Cone‐beam computed tomography results showed great significant difference regarding horizontal bone width at 0 mm and 3 mm from alveolar ridge crest between two groups (P <.05). On the basis of histological outcomes, delightful bony fusion was shown 6‐month postoperatively in ring group. The VAS ratings for pain and swelling reflected similar results between two groups. Conclusions: In‐situ bone ring technique evidently increased and maintained horizontal bone mass at the alveolar ridge crest compared to tent‐pole technique, which might be favorable for implant rehabilitation in anterior area. Meanwhile, no further discomfort was caused according to VAS scoring between two groups. [ABSTRACT FROM AUTHOR]

An unexpected precipitate phase was observed in Mg-20 wt% Dy alloy, with a cuboid morphology not compatible with any shown in the Mg-Dy binary phase diagram. As observed by scanning electron microscopy and energy-dispersive X-ray analysis, the ratio of atomic percent of Dy to Mg is very high in these particles, probably largely because of the poor spatial resolution of that technique but already showing the mismatch with any previously characterized Mg-Dy compound. High-brilliance synchrotron diffraction and transmission electron microscopy experiments confirmed that these particles are composed of DyH2. They are formed during sample preparation at room temperature when hydrogen-containing sources such as water are used. [ABSTRACT FROM AUTHOR]

Enzymatic digestion, the commonly used method of adipose-derived stromal cells isolation, is time consuming and expensive, especially when applied to large volumes of tissue. In the present study, the characteristics of the cells obtained by adipose tissue explant culture were studied. We found that adipose tissue fragments could adhere onto the growth surface of flasks in a very short time after plating and that fibroblast-like cells migrated from the explants and reached confluence. Morphologic analysis and surface markers expression suggested the mesenchymal origin of the cells derived from adipose tissue explants. After in vitro expansion these cells were successfully induced into adipogenic, osteogenic, and chondrogenic lineages, which demonstrated their multipotency. The high growth rate and colony-forming efficiency of explant-derived cells were similar to those of cells obtained by digestion. Furthermore, explant culture gave higher yield of cells than digestion method after primary culture. The experiment of ectopic adipogenesis in nude mice suggested the prospects for tissue engineering of these cells. In conclusion, we obtained multipotent stromal cells from adipose tissue by explant culture, and this method was simple, time saving, and gave a high yield of cells. Therefore, explant culture can be used as an effective way to isolate adipose-derived stromal cells for tissue engineering., (© 2010, Copyright the Authors. Artificial Organs © 2010, International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.)

Mesenchymal stem cells (MSCs) provide us an excellent cellular model to uncover the molecular mechanisms underlying adipogenic differentiation of adult stem cells. PPARgamma had been considered as an important molecular marker of cells undergoing adipogenic differentiation. Here, we demonstrated that expression and phosphorylation of PPARgamma could be found in bone marrow-derived MSCs cultured in expansion medium without any adipogenic additives (dexamethasone, IBMX, insulin or indomethacin). Then, PPARgamma was dephosphorylated in MSCs during the process of adipogenic differentiation. We then found that inhibition of MEK activation by specific inhibitor (PD98059) counteracted the PPARgamma expression and phosphorylation. However, expression and phosphorylation of PPARgamma did not present in MSCs cultured in medium with lower serum concentration. When these MSCs differentiated into adipocytes, no phosphorylation could be detected to accompany the expression of PPARgamma. Moreover, exposure of MSCs to higher concentration of serum induced stronger PPARgamma expression, and subsequently enhanced their adipogenesis. These data suggested that activation of the MEK/ERK signalling pathway by high serum concentration promoted PPARgamma expression and phosphorylation, and subsequently enhanced adipogenic differentiation of MSCs.