Primary Exploration of the Clinical Application of 3D-Printed Complete Dentures.

PURPOSE: To explore the applications of 3D scanning and 3D printing techniques in the restorative treatment of edentulous patients. MATERIALS AND METHODS: A total of 30 edentulous patients (Atwood classes 1 to 4) who visited The 960th Hospital of the People's Liberation Army, Jinan, China, from March 1, 2018 to May 1, 2020 were selected, and the patients were randomly divided into two groups: a traditional complete denture group (group A) and a 3D-printed complete denture group (group B). Each group comprised 15 patients. In group A, the traditional method was used to fabricate complete dentures. In group B, 3D scanning, computer-aided design (CAD), 3D printing, and the duplicate denture technique were used to fabricate the dentures. A single-blinded method was used. Patient satisfaction was measured with a 0-10 visual analog scale (VAS) at four time points: immediately and 1 month, 3 months, and 6 months after denture delivery. SPSS version 22.0 software was used to analyze the data. RESULTS: The ability to speak, ability to chew, and comfort in the two groups gradually improved at the first three time points. VAS scores increased to a satisfactory level after 3 months. The esthetics and stability of the two groups were scored high after the initial delivery. The VAS scores of the two groups regarding esthetics, ability to speak, ability to chew, stability, and comfort were not significantly different (P > .05) at any time point. The number of visits in the 3D-printed complete denture group were significantly decreased in comparison to the traditional group. CONCLUSION: The use of 3D printing for manufacturing complete dentures can rapidly restore edentulous patients and meet patient demands regarding esthetics and function.

Polydopamine Decorated Microneedles with Fe-MSC-Derived Nanovesicles Encapsulation for Wound Healing.

Wound dressing with the capacities of antioxidation, antiinflammation, and efficient angiogenesis induction is expected for effectively promoting wound healing. Herein, a novel core-shell hyaluronic acid (HA) microneedle (MN) patch with ferrum-mesenchymal stem cell-derived artificial nanovesicles (Fe-MSC-NVs) and polydopamine nanoparticles (PDA NPs) encapsulated in the needle tips is presented for wound healing. Fe-MSC-NVs containing multifunctional therapeutic cytokines are encapsulated in the inner HA core of the MN tips for accelerating angiogenesis. The PDA NPs are encapsulated in the outer methacrylated hyaluronic acid (HAMA) shell of the MN tips to overcome the adverse impacts from reactive oxygen species (ROS)-derived oxidative stress. With the gradual degradation of HAMA patch tips in the skin, the PDA NPs are sustainably released at the lesion to suppress the ROS-induced inflammation reaction, while the Fe-MSC-NVs significantly increase the migration, proliferation, and tube formation of human umbilical vein endothelial cells (HUVEC). More attractively, the combination of PDA NPs and Fe-MSC-NVs further promotes M2 macrophage polarization, thereby suppressing wound inflammation. Through in vivo experiment, the Fe-MSC-NVs/PDA MN patch shows an excellent effect for diabetic wound healing. These features of antioxidation, antiinflammation, and pro-angiogenesis indicate the proposed composite core-shell MN patch is valuable for clinical wound healing applications.

Antibacterial Properties of Bilayer Biomimetic Nano-ZnO for Dental Implants.

Dental implant surgery has a relatively high incidence of peri-implantitis. In this research, ZnO nanorods and ZnO nanospheres were synthesized by a hydrothermal method. ZnO nanorods first covered the surface of Ti or Ti-Zr, and ZnO nanospheres were then modified as the outermost layer. By these means a dual antibacterial effect could be realized by the rapid release of ZnO nanospheres and the sustained release of ZnO nanorods. Subsequent studies implied that this ZnO nanorods-nanospheres hierarchical structure (NRS) could be stably loaded on the surface of roughened Ti and Ti-Zr slices. The modified materials not only showed excellent antibacterial activities against both Escherichia coli and Staphylococcus aureus but also showed low cellular cytotoxicity. This ZnO NRS structure is thus expected to be used as a general antimicrobial coating on the surface of Ti (Ti-Zr) in dental implant surgery.

Porous scaffolds from droplet microfluidics for prevention of intrauterine adhesion.

Severe intrauterine adhesions (IUAs) have a great negative impact on women's psychological and reproductive health. It remains a significant challenge to prevent postoperative IUAs because of the complications of various clinical preventive measures and incompatibility of uterine cavity morphology. Herein, we present a new drug-loadedporous scaffold based on a microfluidic droplet template, which combines the characteristics of the artificial biocompatible material GelMA and the natural polysaccharide material Na-alginate. By changing the containers that collect the microfluidic droplets, the porous scaffold conforming to the shape of the uterine cavity could be obtained. The porous structure, mechanical property, and flexibility impart the scaffold with compressibility and send it to the uterus through the vagina. In addition, the external-internal connected open structures could load and control the release of drugs to repair the damaged region continuously in vivo. To verify the antiadhesion and repair of drug-loaded porous scaffolds, we tested the system in the rat model of IUAs, and it was demonstrated that the system had the ability to improve neovascularization, cellularize the damaged tissue, and repair the endometrium. These features provide the drug-loaded porous scaffolds with new options for the improvement of postoperative IUAs. STATEMENT OF SIGNIFICANCE: Intrauterine adhesions are caused by various causes of damage to the endometrial basal layer, thus leading to part or entire adhesions in the cervical or uterine cavity. Clinically, various preventive measures reach the barrier effect through the physical barrier, which are difficult to further promote the repair of the damaged endometrium, and most of them have apparent side effects. This study aims to prepare compressible and biodegradable three-dimensional porous drug-loading biological scaffolds. GelMA and Na-alginate have desirable biocompatibility. The interconnect porous scaffolds, which were prepared through the combination of biomaterials and single emulsion microfluidics, not only have compressibility but also provide space for drug delivery and release. This system can further promote the repair of the endometrium while preventing adhesion.

Aptamer-based hydrogel barcodes for the capture and detection of multiple types of pathogenic bacteria.

Rapid and sensitive diagnosing hematological infections based on the separation and detection of pathogenic bacteria in the patient's blood is a significant challenge. To address this, we herein present a new barcodes technology that can simultaneously capture and detect multiple types of pathogenic bacteria from a complex sample. The barcodes are poly (ethylene glycol) (PEG) hydrogel inverse opal particles with characteristic reflection peak codes that remain stable during bacteria capture on their surfaces. As the spherical surface of the particles has ordered porous nanostructure, the barcodes can provide not only more surface area for probe immobilization and reaction, but also a nanopatterned platform for highly efficient bioreactions. In addition, the PEG hydrogel scaffold could decrease the non-specificity adsorption by its anti-adhesive effect, and the decorated aptamer probes in the scaffolds could increase the sensitivity, reliability, and specificity of the bacteria capture and detection. Moreover, the tagged magnetic nanoparticles in the PEG scaffold could impart the barcodes with controllable movement under magnetic fields, which can be used to significantly increase the reaction speed and simplify the processing of the bioassays. Based on the describe barcodes, it was demonstrated that the bacteria could be captured and identified even at low bacterial concentrations (100 CFU mL-1) within 2.5h, which is effectively shortened in comparison with the "gold standard" in clinic. These features make the barcodes ideal for capturing and detecting multiple bacteria from clinical samples for hematological infection diagnostics.

Hierarchically porous composite microparticles from microfluidics for controllable drug delivery.

Abdominal wall defect repair remains a major clinical need, and a particle-based controllable drug delivery system offers a solution to this problem. Here, we present a new type of hierarchically porous microparticles (HPMs) composed of poly(lactic-co-glycolic acid) (PLGA) and hollow mesoporous silica nanoparticles (HMSNs) for the delivery. The HPMs are generated by drying microfluidic emulsion templates of HMSNs-dispersed PLGA solution. The resultant HPMs have tailorable porous structures, that provide a three-hierarchy architecture for the controlled release of actives. The first hierarchy is formed for controlling the drug release via physical absorption as a result of the presence of the HMSNs in the HPMs. The second hierarchy channels with small pores scattered throughout the surface of the HPMs are formed during evaporation of the solvent. The third hierarchy with openings on the surface of the HPMs is formed as a result of the inner droplets leaking out of the double emulsion templates during the PLGA solidification. Thus, by manipulating the flow of solutions during the microfluidic emulsification, the porous structures of HPMs can be easily and precisely adjusted, and the loaded drugs are delivered at the required rate. These features of the HPMs make them ideal for repairing abdominal wall defects.

Effects of Four Different Crown Materials on the Peri-Implant Clinical Parameters and Composition of Peri-Implant Crevicular Fluid.

This study aimed to identify the preferred crown material by measuring the peri-implant clinical parameters and the concentrations of receptor activator of nuclear factor-κB ligand (RANKL), osteoprotegerin (OPG), and calcium in peri-implant crevicular fluid (PICF) with 4 different crown materials. A total of 196 patients with a single missing posterior tooth received crown restoration with cobalt-chromium (Co-Cr) porcelain-fused-to-metal (PFM; n = 50), aurum platinum (Au-Pt) PFM (n = 48), titanium (Ti) PFM (n = 52), or zirconia (Zi) all-ceramic crown (n = 46). Fifty-one natural counterpart teeth served as controls. Before and 12 months after restoration, the PICF was collected, and the concentrations of RANKL, OPG, and calcium were quantified. The peri-implant clinical parameters (plaque index, bleeding on probing, and probing depth [PD]) and gingival crevicular fluid (GCF) volumes were assessed. Twelve months after restoration, the PD and GCF volumes for the 4 experimental groups were significantly greater than those for the control group and before restoration. The Co-Cr group showed the greatest PD, GCF volume, RANKL/OPG, RANKL, and calcium ion concentration, followed by the Au-Pt group. The Ti group had the highest OPG concentration, followed by the Zi group. The RANKL and calcium ion concentrations of the Ti and Zi groups were the smallest. The Ti group had the smallest RANKL/OPG ratio, followed by the Zi group. Different crown materials differentially affected the PD, volume, RANKL/OPG ratio, OPG, RANKL, and calcium concentration. Among the 4 tested crown materials, Zi and Ti are preferred. However, some limitations of the present study should be considered.

Distraction osteogenesis in the dog mandible under 60-Gy irradiation.

OBJECTIVE: The objective of this study was to explore the probability of distraction osteogenesis (DO) in the irradiated dog mandible after 60-Gy irradiation. STUDY DESIGN: Fourteen Chinese dogs were randomly divided into 2 groups. Twelve dogs received a preoperative unilateral irradiation from (60)Co (group R) in the mandible with a total dose of 24.8 Gy in four 6.2-Gy fractions (biologically equivalent to 60 Gy/25 fractions). The other 2 dogs without irradiation served as the control (group C). Bilateral corticotomies were made 6 months after completion of irradiation. Bone distraction was activated at a rate of 0.5 mm twice daily for 10 days after a 1-week latency period, followed by a consolidation phase of 8 weeks. The inferior alveolar nerve (IAN) underwent electrophysiologic analysis. Dog mandibles were subsequently subjected to histologic and radiographic analysis. RESULTS: All the animals had successful distractions. After 8 weeks of consolidation, no difference was found between the percentage area of new bone in both groups. New bone was more mature and organized in group C than in group R. The action potential of IAN showed corresponding alternation during the irradiation and distraction process. CONCLUSIONS: Based on this study it seems that DO may be feasible in dog mandible under 60-Gy irradiation. Further research is indicated.

Character of distracted bone in irradiated canine mandibles and electrophysiological changes in the inferior alveolar nerve.

Our aim was to explore the character of distracted bone in irradiated canine mandibles and the electrophysiological changes in the irradiated inferior alveolar nerve (IAN). Twelve Chinese dogs were studied, 10 of which were given unilateral irradiation of (60)Co in the mandible with a total dose of 22.8Gy in four 5.7Gy fractions (biologically equivalent to 50Gy/25 fractions) (experimental group). The other two dogs were not irradiated and served as controls. All had a bilateral corticotomy 3 months after irradiation. After a 1-week latency period distraction of the mandible was activated at a rate of 0.5mm twice daily for 10 days, followed by a consolidation phase of 8 weeks. New bone was assessed by radiographic, histological, and single-photon electron computed tomographic (SPECT) analysis. The IAN was analysed electrophysiologically. One dog in the experimental group was excluded from the study with anaesthetic problems. After 8 weeks of consolidation there was no difference between the percentage area of new bone in the two groups. New bone was more mature and organised in the control group than in the experimental group. SPECT analysis showed that there was active osteogenic activity in dogs in the experimental group. The action potential of the IAN showed corresponding changes during the irradiation and distraction processes. We conclude that distraction osteogenesis is feasible in previously irradiated canine mandibles and IAN.