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Purpose: Complex bone defects with a horizontal and vertical combined deficiency pose a clinical challenge in implant dentistry. This study reports the case of a young female patient who presented with a perforating bone defect in the aesthetic zone. Materials and methods: Based on prosthetically guided bone regeneration, virtual 3D bone augmentation was planned. A 3D printed customised titanium mesh and the autogenous bone ring technique were then utilised simultaneously to achieve a customised bone contour. After 6 months, the titanium mesh was removed and connective tissue grafting was performed. Finally, implants were placed and the provisional and definitive prostheses were delivered following a digital approach. Vertical and horizontal bone gain, new bone density, pseudo-periosteum type and marginal bone loss were measured. Planned bone volume, regenerated bone volume and regeneration rate were analysed. Results: Staged tooth shortening led to a coronal increase in keratinised mucosa. The customised titanium mesh and bone ring technique yielded 14.27 mm vertical bone gain and 12.9 mm horizontal bone gain in the perforating area. When the titanium mesh was removed, the reopening surgery showed a Type 1 pseudo-periosteum (none or < 1 mm), and CBCT scans revealed a new bone density of ~550 HU. With a planned bone volume of 1063.55 mm3, the regenerated bone volume was 969.29 mm3, indicating a regeneration rate of 91.14%. The 1-year follow-up after definitive restoration revealed no complications except for 0.55 to 0.60 mm marginal bone loss. Conclusion: Combined application of customised titanium mesh and an autogenous bone ring block shows promising potential to achieve prosthetically guided bone regeneration for complex bone defects in the aesthetic zone. [ABSTRACT FROM AUTHOR]

This study aimed to estimate the radiographic outcomes of the alveolar ridge splitting (ARS) technique combined with guided bone regeneration (GBR) and compare its efficacy with GBR alone in maxillary anterior narrow ridges. Forty patients with 51 implants in the ARS group and 40 patients with 49 implants in the GBR group were included. The buccal bone thickness (BBT) at 0 to 4 mm from the implant shoulder immediately and 6 months postoperative were analyzed using cone beam computed tomography. The BBT at both time points had no statistical disparities between the two groups (P > .05). However, BBT changes indicated significant disparities, with more BBT preservation in the ARS group (P < .05). Compared with GBR alone, the ARS technique combined with GBR, despite obvious buccal bone diminution, could be a reliable modality for treating ridge width deficiency in the anterior maxilla. [ABSTRACT FROM AUTHOR]

With the increasing demand for innovative therapies, biodegradable magnesium has attracted more and more attention, which could avoid secondary surgery and reduce complications. Until now, plenty of researchers take part in the research & development of this field, and many articles have been published every year. However, it is a huge challenge to predict research trends and definite topics for researchers, which could result in low research value, wasted resources and even slowed medical device transformation. Usually, reviews summarize a specific topic, such as alloy elements, coating designs, degradable properties, etc. Deriving key indicators from a large amount of data with the help of statistical analysis, make a historical review, current situation analysis, and future prediction more convincing. Herein, it has been conducted a bibliometric study according to 2669 publications collected from the Web of Science (WOS) database from 2005 to 2021. By analyzing some key factors, including annual publications, keywords, country contributions, authors as well as institutions, the evolution of biodegradable magnesium is objectively studied. The research trends of biodegradable magnesium alloys are corrosion resistance, the influence of microstructural control on mechanical behavior and bio-functions of implants in a chronological manner. The co-occurrence mapping of the countries and authors suggests that current in-depth research and development of magnesium is more emphasis on institutional and international cooperation. [ABSTRACT FROM AUTHOR]

Telescopic overdentures supported by the combination of natural teeth and implants have been thought a valuable treatment for the severely compromised partially edentulous patients. But the combination of teeth and implants involves highly complex biomechanical problems. This study is to evaluate biomechanical behaviors of the natural abutment teeth with the treatment of combined tooth-implant supported telescopic crown prostheses in mandible through 3D FEA. According to this study, the prosthetic option supported by a combination of teeth and implants and retained by double crowns could protect teeth and their periodontal support tissues acting as a rigid splint, and may be a valuable treatment option for partially edentulous patients with severely reduced remaining teeth in mandible. [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. [ABSTRACT FROM AUTHOR]

Mesenchymal stem cells (MSCs) provide us an excellent cellular model to uncover the molecular mechanisms underlying adipogenic differentiation of adult stem cells. PPARγ had been considered as an important molecular marker of cells undergoing adipogenic differentiation. Here, we demonstrated that expression and phosphorylation of PPARγ could be found in bone marrow–derived MSCs cultured in expansion medium without any adipogenic additives (dexamethasone, IBMX, insulin or indomethacin). Then, PPARγ was dephosphorylated in MSCs during the process of adipogenic differentiation. We then found that inhibition of MEK activation by specific inhibitor (PD98059) counteracted the PPARγ expression and phosphorylation. However, expression and phosphorylation of PPARγ 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 PPARγ. Moreover, exposure of MSCs to higher concentration of serum induced stronger PPARγ expression, and subsequently enhanced their adipogenesis. These data suggested that activation of the MEK/ERK signalling pathway by high serum concentration promoted PPARγ expression and phosphorylation, and subsequently enhanced adipogenic differentiation of MSCs. [ABSTRACT FROM AUTHOR]