[Brief Analysis of Clinical Evaluation Concerns of Personalized Abutments and Abutment Crown Bridge Products].

Objective: The applications of personalized abutments and abutment crown bridge products have increased year by year, but there is no clear requirement for clinical evaluation of the same variety of such products. This study mainly introduces the clinical evaluation concerns of personalized abutments and abutment crown bridge products, in order to provide reference for the declaration and registration of such products. Methods: The clinical evaluation of personalized abutments and crown bridge products are summarized, and the research content of clinical evaluation is clarified. Results: The clinical evaluation requirements that need to be considered by enterprises are introduced. Conclusion: Personalized abutment and abutment crown bridge products can refer to this study when they are launched in China, mainly using in vitro performance comparison tests for equivalence verification.

[Analysis on Focus of Clinical Evaluation of Dental Implants (Systems)].

From the perspective of technical evaluation, this article introduces the focus of clinical evaluation of dental implants (systems) in comparison with the comparable devices and discusses the clinical evaluation of such products，combined with the clinical evaluation review of dental implants (systems) products in recent years, in order to provide reference for the registration of these products.

Incorporation of bacteriophages in polycaprolactone/collagen fibers for antibacterial hemostatic dual-function.

Effective and affordable, antibacterial and hemostatic materials are of great interests in clinical wound care practices. Herein, Enterobacteria phage T4 were incorporated in polycaprolactone/collagen I (PCL-ColI) nanofibers via electrospinning in order to eradicate Escherichia coli infection and meanwhile establish hemostasis. Tensile strength of the membrane was significantly enhanced with increased PCL ratio. Those with a collagen component above 70% were demonstrated to be more hemostatic with shorter hemostatic time and smaller amount of bleeding. On the other hand, the T4 phage incorporated PCL-ColI membrane (PCL:ColI = 30%/70%, w/w) exhibited the optimal antibacterial efficiency (above 90%). The in vivo evaluation indicated that the PCL-ColI B (30%:70%, w/w) membrane fully degraded in 8 weeks and no obvious pathological reaction to muscle and subcutaneous layer tissues in the back of rabbit was found. The novel fibrous hemostatic materials coupled with phage therapy hold great promise in designing novel antibacterial, hemostatic wound dressings that addresses concerns of antibiotic resistance. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 2588-2595, 2018.

Reinforced collagen with oxidized microcrystalline cellulose shows improved hemostatic effects.

Sponges composed of different levels of composite collagen/oxidized microcrystalline cellulose (collagen/OMCC), denoted M1-M4, were studied to improve the hemostatic effect of single-collagen sponges. Surface morphological observations showed that structural combinations and intermolecular interactions occurred between collagen and OMCC in the composites. M2 presented the best physical properties and platelet activation and was thus selected for the investigations of the in vitro coagulation time and hemostatic and biological effects on animals. The results illustrated that M2 could reduce the length of the activated partial thromboplastin time (APTT) and thrombin time (TT) and presented rapid hemostatic efficiency in the two injury models (P<0.05). These findings were used to evaluate the hemostatic mechanism of M2, which can promote blood absorption and platelet activation and could be directly involved in the intrinsic coagulation pathway to accelerate hemostasis. Furthermore, M2 was not cytotoxic and was completely biodegraded in subcutaneous tissue within 28days.

Preparation of pH-responsive mesoporous hydroxyapatite nanoparticles for intracellular controlled release of an anticancer drug.

A well-defined core-shell nano-carrier (PAA-MHAPNs) was successfully synthesized based on a graft-onto method by using mesoporous hydroxyapatite nanoparticles (MHAPNs) as the core and polyacrylic acid (PAA) as the shell. Given that MHAPNs are regarded as one of the most promising drug delivery vehicles due to their excellent performance and the nature of their cancer cell anti-proliferative effect, and the grafted PAA, as a pH-responsive switch, could improve the loading amount of the drug doxorubicin hydrochloride (DOX) effectively by electrostatic interactions, all these advantages mean that the designed models show promise for application in pH-responsive drug delivery systems. The loading content and entrapment efficiency of DOX could reach up to 3.3% and 76%, respectively. The drug release levels of the constructed DOX@PAA-MHAPNs were low under normal physiological conditions (pH 7.4), but they could be increased significantly with a decrease of pH. Cytotoxicity assays indicated that the PAA-MHAPNs was biocompatible, and more importantly, the DOX@PAA-MHAPNs demonstrated an obvious ability to induce apoptosis of cancer cells. Overall, the synthesized systems should show great potential as drug nanovehicles with excellent biocompatibility, high drug loading, and pH-responsive features for future intracellular drug delivery.