Robust and self-lubricating polyvinyl alcohol tubes with a mucosa-like hierarchical architecture for endotracheal intubation.

Mechanical mismatch between interventional intubation tubes and human tissues often triggers inevitable friction and causes secondary injury to patients during interventional therapy. Herein, we propose a fabrication strategy of a self-lubricating polyvinyl alcohol (PVA) tube by industrial extrusion technology followed by simple infiltration with water. First, biocompatible glycerin was introduced to weaken the intrinsic hydrogen interaction of PVA by new molecular complexation, broadening the gap between the melting and decomposition temperatures and enabling the stable extrusion of the PVA tube. Subsequently, the as-prepared PVA tube was infiltrated with an aqueous solution to construct a strong hydrogen bonding network between PVA and water molecules, forming a soft hydration layer similar to the upper epithelium layer of mucosa. Benefiting from the solid and liquid properties of the hydration layer as well as the small proportion relative to the whole, the infiltrated PVA tube exhibited excellent hydration lubrication behavior and robust mechanical property. The friction coefficient, tensile strength and elongation at break were measured to be 0.05, 26.2 MPa and 654%, respectively, surpassing the values of 0.5, 16.4 MPa and 240% observed in a commercial polyvinyl chloride tube. In vitro, the PVA intubation tube demonstrated significant biocompatibility, and short-term exposure exhibited minimal impacts on the morphology and proliferation of L929 cells. Ultimately, the potential of the infiltrated PVA tube for interventional intubation was demonstrated successfully using an in vivo rabbit model, providing a new idea for the follow-up development of interventional intubation tubes.

Generating bioactive and antiseptic interfaces with nano-silver hydroxyapatite-based coatings by pulsed electrochemical deposition for long-term efficient cervical soft tissue sealing.

Infections related to osseointegrated implants have sparked the interest in studying titanium modification for long-term effective soft tissue sealing. Constructing a silver (Ag)-hydroxyapatite (HA) coating is regarded as an effective strategy for integrating antibiosis with osteanagenesis; however, the outcome for long-term cervical soft tissue sealing in vivo is compromised. It is challenging to construct an Ag-HA coating for long-term efficient soft tissue integration that instills a maximum antibacterial effect while retaining favorable bioactivity to normal gingival mesenchymal cells in vivo. In this study, we employed gradient concentrations of Ag/CaP by pulsed electrochemical deposition to fabricate optimal Ag-HA nanocoatings. By physicochemical analyses, these uniform coatings were mainly formed with spherical metallic and hydroxyapatite nanoparticles, which facilitated good hydrophilicity, moderate rough surfaces and corrosion protection. Furthermore, the nanocoating of the 1.5Ag/CaP group exhibited superior performances in dental follicle cells' proliferation, osteogenic differentiation and antibacterial properties mainly through direct contact inhibition and partially through sustained silver ion release, which resulted in functional cervical soft tissue sealing in beagles lasting for one year. Our investigations provide a feasible strategy to balance the long-term antibacterial demand and bioactive induction around osseointegrated implants for long-term efficient cervical soft tissue sealing.

Biomimetic Peridontium Patches for Functional Periodontal Regeneration.

The unique structure of the periodontium, including the alveolar bone, cementum, and periodontal ligament (PDL), presents difficulties for the regeneration of its intricate organization. Irreversible structural breakdown of the periodontium increases the risk of tooth loosening and loss. Although the current therapies can restore the periodontal hard tissues to a certain extent, the PDL with its high directionality of multiple groups with different orientations and functions cannot be reconstructed. Here, biomimetic peridontium patches (BPPs) for functional periodontal regeneration using a microscale continuous digital light projection bioprinting method is reported. Orthotopic transplantation in the mandibles shows effective periodontal reconstruction. The resulting bioengineered tissues closely resembles natural periodontium in terms of the "sandwich structures," especially the correctly oriented fibers, showing different and specific orientation in different regions of the tooth root, which has never been found in previous studies. Furthermore, after the assessment of clinically functional properties it is found that the regenerative periodontium can achieve stable tooth movement under orthodontic migration force with no adverse consequences. Overall, the BPPs promote reconstruction of the functional periodontium and the complex microstructure of the periodontal tissue, providing a proof of principle for the clinical functional treatment of periodontal defects.

Comparison of Failure and Complication Risks of Porcelain Laminate and Indirect Resin Veneer Restorations: A Meta-Analysis.

PURPOSE: To evaluate and compare the failure and complication risks of porcelain laminate and indirect resin veneer restorations (VRs) by means of a meta-analysis. METHODS: An electronic database search was performed in MEDLINE (PubMed), EMBASE (Ovid), and the Cochrane Central Register of Controlled Trials (CENTRAL) databases, and a gray literature search was performed on OpenGrey. All database searches were completed by March 2018. Two authors individually screened the literature according to the inclusion and exclusion criteria. The quality and risk of bias of the included studies were evaluated using the Newcastle-Ottawa scale (NOS) and the Cochrane Handbook for Systematic Reviews of Interventions (CHSRI). The Mantel-Haenszel method was used to synthesize the data of the included studies. All statistical analyses were performed using the software Stata 14.0, and the results were expressed as risk ratio (RR) with 95% confidence interval (CI). RESULTS: Five studies-two randomized controlled trials (RCTs) and three clinical controlled trials (CCTs)-were included in this review. Of the three CCTs, two were assessed to be low quality, and the third was considered high quality. The two RCTs were rated as unclear risk of bias. The meta-analysis results showed the risk of failure for indirect resin VRs was higher than for porcelain laminate VRs (RR: 0.15, 95% CI: 0.06-0.40; P = .000). Fracture and debonding were the main complications leading to failure. For risk of fracture, an RR of 0.18 (95% CI: 0.04-0.71) and a statistically significant difference (P = .015) were found in favor of porcelain laminate VRs. For risk of debonding, there was no statistically significant difference (P = .108) found between the two types of VRs. The results of the sensitivity analysis (RR: 0.09, 95% CI: 0.02-0.45; P = .004) suggested that this conclusion was reliable. CONCLUSION: The survival rate of porcelain laminate VRs was higher than indirect resin VRs, and the latter had a higher risk of fracture. However, there was no statistically significant difference in the risk of debonding between the two types of VRs. Porcelain laminate VRs have a better prognosis compared to indirect resin VRs, which provides an evidence-based reference for the selection of VRs in clinical practice.