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Existing bone tissue engineering strategies aim to achieve minimize surgical trauma, stabilize the injured area, and establish a dynamic osteogenic microenvironment. The cutting‐edge bone glue developed in this study satisfies these criteria. Inspired by the excellent adhesive properties of mussels, herein, a super osteogenic glue (L‐DPZ) that integrates poly(vinyl alcohol), L‐dopa amino acid, and zeolitic imidazolate framework‐8 characterized by catechol–metal coordination is used to successfully adhere to hard tissue with a maximum adhesive strength of 10 MPa, which is much higher than those of commercial and previously reported bone glues. The stable hard tissue adhesion also enables it to adhere strongly to luxated or broken teeth, Bio‐Oss (a typical bone graft material), and splice fragments from comminuted fractures of the rabbit femur. Then, it is testified that the L‐DPZ hydrogels exhibit satisfactory biocompatibility, stable degradability, and osteogenic ability in vitro. Moreover, the ability to anchor Bio‐Oss and sustained osteogenesis of L‐DPZ result in satisfactory healing in calvarial bone defect models in rabbits, as observed by increased bone thickness and the ingrowth of new bone tissue. These results are expected to demonstrate solutions to clinical dilemmas such as comminuted bone fracture fixation, bone defect reconstruction, and teeth dislocation replantation. [ABSTRACT FROM AUTHOR]

Risk of implant failure increases profoundly in patients with pre‐existing conditions (e.g., diabetes). Current therapies adopt a one‐sided focus on the direct antibacterial properties of biomaterials and osteogenesis stimulation. However, in this study it is demonstrated that a "chain armor" structure (Ce‐TA) that mainly targets the regulation of the local pathological microenvironment, provides a novel solution to scavenge reactive oxygen species (ROS) by simulating superoxide dismutase and catalase and significantly improving osteointegration under diabetic conditions. Ce‐TA based on a metal phenolic network biological functional interface is successfully constructed. Ce‐TA, an ultrathin armor structure, is biocompatible and facile. Through in vitro assays it is demonstrated that Ce‐TA reshapes the diabetic microenvironment into a regenerative one in a microenvironment‐responsive manner, where Ce‐TA regulates hypoxia‐inducible factor 1α (HIF‐1α) activity by reducing the level of mitochondrial ROS, and effectively alleviates mitochondrial dysfunction and reprogrammes macrophages to a pro‐healing state. Furthermore, it is confirmed that Ce‐TA shows excellent therapeutic effects on the reducing postoperative infection and enhances osteointegration of intra‐osseous implants in diabetic rat models. The proposed strategy opens up a promising opportunity for repurposing metals with intrinsic enzyme‐like activity for the goal of enhancing the osteointegration of devices with orthopedic and dental applications among diabetic patients. [ABSTRACT FROM AUTHOR]

GRAPH Corrected figure for original Figure S17. GRAPH Corrected figure of original Figure 2d. Safeguarding Osteointegration in Diabetic Patients: A Potent "Chain Armor" Coating for Scavenging ROS and Macrophage Reprogramming in a Microenvironment-Responsive Manner. [Extracted from the article]

Cone beam computed tomography (CBCT) has obvious advantages over regular radiography in diagnosis of complex diseases. Objective of this study is to report a case of a mandibular jaw ameloblastoma recurring cyst, which represents a benign tumor of odontogenic epithelium, using CBCT imaging technology. CBCT examination of the patient suffering with recurrent lower jaw cyst (relapsing four years after surgery) showed a decrease in irregular bone density and appearance of a honeycomb pattern (3.5 cmx2.5 cmx1.8 cm) in the right lower jaw. This suggests that the lesion is more likely to be an ameloblastoma. Preoperative tissue biopsy and pathological examination of surgical sample confirmed the diagnosis. Surgical resection of the diseased tissue and autogenous bone grafting in the mandible was performed. Postoperative CBCT examination showed that the bone defect healed well, without recurrence of the tumor 22 months postoperatively. In conclusion, the rotated 3D CBCT images clearly displays the exact size, location, borders and internal changes of the tumor in the jaw cyst itself and the adjacent tissues. Thus, the dental CBCT allows clinicians to better evaluate lesions, leading to better treatment outcomes. [ABSTRACT FROM AUTHOR]

Periodontitis is an inflammatory disease characterized by tooth loss and alveolar bone resorption. Bacteria are the original cause of periodontitis, and excess reactive oxygen species (ROS) encourage and intensify inflammation. In this study, a mussel-inspired and MnO 2 NPs-reinforced adhesive hydrogel capable of alleviating periodontitis with improved antibacterial and antioxidant abilities was developed. The hydrogel was created by combining polyvinyl alcohol (PVA), 3,4-dihydroxy-d-phenylalanine (DOPA), and MnO 2 nanoparticles (NPs) (named PDMO hydrogel). The hydrogel was demonstrated to be able to scavenge various free radicals (including total ROS─O 2 •- and OH • ) and relieve the hypoxia in an inflammatory microenvironment by scavenging excess ROS and generating O 2 due to its superoxide dismutase (SOD)/catalase (CAT)-like activity. Besides, under 808 nm near-infrared (NIR) light, the photothermal performance of the PDMO hydrogel displayed favorable antibacterial and antibiofilm effects toward Escherichia coli , Staphylococcus aureus , and Porphyromonas gingivalis (up to nearly 100% antibacterial rate). Furthermore, the PDMO hydrogel exhibited favorable therapeutic efficacy in alleviating gingivitis in Sprague-Dawley rats, even comparable to or better than the commercial PERIO. In addition, in the periodontitis models, the PDMO2 group showed the height of the residual alveolar bone and the smallest shadow area of low density among other groups, indicating the positive role of the PDMO2 hydrogel in bone regeneration. Finally, the biosafety of the PDMO hydrogel was comprehensively investigated, and the hydrogel was demonstrated to have good biocompatibility. Therefore, the developed PDMO hydrogel provided an effective solution to resolve biofilm recolonization and oxidative stress in periodontitis and could be a superior candidate for local drug delivery system in the clinical management of periodontitis with great potential for future clinical translation.

The regeneration of bone defects in patients with diabetes mellitus (DM) is remarkably impaired by hyperglycemia and over-expressed proinflammatory cytokines, proteinases (such as matrix metalloproteinases, MMPs), etc. In view of the fact that exosomes represent a promising nanomaterial, herein, we reported the excellent capacity of stem cells from apical papilla-derived exosomes (SCAP-Exo) to facilitate angiogenesis and osteogenesis whether in normal or diabetic conditions in vitro . Then, a bioresponsive polyethylene glycol (PEG)/DNA hybrid hydrogel was developed to support a controllable release of SCAP-Exo for diabetic bone defects. This system could be triggered by the elevated pathological cue (MMP-9) in response to the dynamic diabetic microenvironment. It was further confirmed that the administration of the injectable SCAP-Exo-loaded PEG/DNA hybrid hydrogel into the mandibular bone defect of diabetic rats demonstrated a great therapeutic effect on promoting vascularized bone regeneration. In addition, the miRNA sequencing suggested that the mechanism of dual-functional SCAP-Exo might be related to highly expressed miRNA-126-5p and miRNA-150-5p. Consequently, our study provides valuable insights into the design of promising bioresponsive exosome-delivery systems to improve bone regeneration in diabetic patients.

Background: Schneiderian membrane (SM) perforation is a major complication of maxillary sinus elevation with simultaneous bone grafting, yet under this scenario there is no standard biomaterial that maximizes favorable tissue healing and osteogenic effects., Purpose: To compare the effect of advanced platelet-rich fibrin (A-PRF) and collagen membrane (CM) on a perforated SM with simultaneous bone grafting in a maxillary sinus elevation model., Materials and Methods: After perforation of the SM was established, 24 animals were randomly divided into two groups: (i) group CM: CM and deproteinized bovine bone mineral (DBBM) ( n = 12), (ii) group A-PRF: A-PRF and DBBM ( n = 12). Radiographic and histological evaluations were performed at 1 and 4 weeks post-operation., Results: At 1 week, an intact SM was found in group A-PRF. At each time point, the number of inflammatory cells at the perforated site was higher in group CM, and the area of new osteoid formation was significantly greater in group A-PRF ( p < 0.0001). At 4 weeks, the osteogenic pattern was shown as from the periphery to the center of the sinus cavity in group A-PRF., Conclusion: The higher elasticity, matching degradability, and plentiful growth factors of A-PRF resulted in a fully repaired SM, which later ensured the two osteogenic sources from the SM to generate significant new bone formation. Thus, A-PRF can be considered to be a useful bioactive tissue-healing biomaterial for SM perforation with simultaneous bone grafting., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2020 Xin, Yuan, Mu, Li, Song and Chen.)