A Systematic Approach for Making 3D-Printed Patient-Specific Implants for Craniomaxillofacial Reconstruction

Craniomaxillofacial reconstruction implants, which are extensively used in head and neck surgery, are conventionally made in standardized forms. During surgery, the implant must be bended manually to match the anatomy of the individual bones. The bending process is time-consuming, especially for inexperienced surgeons. Moreover, repetitive bending may induce undesirable internal stress concentration, resulting in fatigue under masticatory loading in vivo and causing various complications such as implant fracture, screw loosening, and bone resorption. There have been reports on the use of patient-specific 3D-printed implants for craniomaxillofacial reconstruction, although few reports have considered implant quality. In this paper, we present a systematic approach for making 3D-printed patient-specific surgical implants for craniomaxillofacial reconstruction. The approach consists of three parts: First, an easy-to-use design module is developed using Solidworks® software, which helps surgeons to design the implants and the axillary fixtures for surgery. Design engineers can then carry out the detailed design and use finite-element modeling (FEM) to optimize the design. Second, the fabrication process is carried out in three steps: ① testing the quality of the powder; ② setting up the appropriate process parameters and running the 3D printing process; and ③ conducting post-processing treatments (i.e., heat and surface treatments) to ensure the quality and performance of the implant. Third, the operation begins after the final checking of the implant and sterilization. After the surgery, postoperative rehabilitation follow-up can be carried out using our patient tracking software. Following this systematic approach, we have successfully conducted a total of 41 surgical cases. 3D-printed patient-specific implants have a number of advantages; in particular, their use reduces surgery time and shortens patient recovery time. Moreover, the presented approach helps to ensure implant quality

CdS-sensitized ZnO nanorod arrays coated with TiO2 layer for visible light photoelectrocatalysis

A novel ZnO/CdS/TiO2 nanorod array composite structure was fabricated by depositing CdS-sensitized layer onto ZnO nanorod arrays via chemical bathing deposition and subsequently coated by TiO2 protection layer via a vacuum dip-coating process. The films were characterized by x-ray diffraction, field emission scanning electron microscopy, energy dispersive spectrum, and UV-Vis diffuse reflectance spectroscopy. For the films severed as the photoanodes, linear sweep voltammetry and transient photocurrent (i(ph)) were investigated in a three-electrode system. The photoelectrocatalytic activity was evaluated by the degradation of methylene blue (MB) under visible light irradiation. The results show that the oriented ZnO nanorods are adhered by relatively uniform CdS-sensitized layer and coated with TiO2 layer. Both the coated and uncoated CdS-sensitized ZnO nanorod arrays exhibit the visible light response and the photoelectrocatalytic activity on the degradation of MB under visible light irradiation. The ZnO/CdS/TiO2 nanorod array film possesses stable and superior photoelectrocatalytic performance owing to the TiO2 thin layer protecting the CdS from photocorrosion.</p

CdSe-sensitized TiO2 nanotube array film fabricated by ultrasonic-assisted electrochemical deposition and subsequently wrapped with TiO2 thin layer for the visible light photoelectrocatalysis

A composite structure, TiO2 nanotube array/CdSe nanoparticle/TiO2 layer, was fabricated by inserting CdSe nanoparticles into anodized TiO2 nanotube arrays via ultrasonic-assisted cyclic voltammetry electrochemical deposition and subsequently wrapped by a TiO2 thin layer via TiCl4 hydrolysis. The films were characterized by X-ray diffraction, field emission scanning electron microscopy, energy dispersive spectroscopy and UV-vis diffuse reflectance spectroscopy. For the film used as the photoanode, linear sweep voltammetry and transient photocurrent were investigated in a three-electrode system under visible light illumination. And the photocatalytic activity was evaluated by the oxidation of glucose in the supporting electrolyte at different potential bias under visible light illumination. The results showed that CdSe nanopartides are prone to disperse into the nanotube arrays via cyclic voltammetry electrochemical deposition under ultrasonic condition. Increasing cyclic voltammetry cycle increases the loading of CdSe on the TiO2 nanotube arrays. The CdSe-sensitized TiO2 nanotube array films exhibit a wide-absorption response in the visible light region. The TiO2 nanotube array/CdSe/TiO2 film, prepared by ultrasonic-assisted electrochemical deposition with 50 cyclic voltammetry cycles and subsequently coating a TiO2 thin layer, exhibits better protection against photocorrosion of CdSe. The TiO(2)NTA/CdSeffiO(2) film possesses visible light photoelectrocatalytic activity on the degradation of glucose. (C) 2011 Elsevier B.V. All rights reserved

Biodegradable Polymer/TiO2 Nanotubes Loaded Roxithromycin as Nanoarray Capsules for Long-Lasting Antibacterial Properties of Titanium Implant

Bacterial infection is one of the main reasons for the clinical failure of oral titanium restorations. In this study, biodegradable polymer/TiO2 nanotube nanoarray capsules were constructed on a titanium substrate surface to locally deliver drugs for long-lasting antibacterial properties. Anodization was applied to prepreparation TiO2 nanotube array film on titanium substrate, and then, the upward opening TiO2 nanotubes were sealed with biodegradable polymer (chitosan and polyethylene glycol) through electrochemical deposition. Scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (XPS) were used to analyze the characterization of this system. The drug release characteristics and the antibacterial activity demonstrated that the polymer coating significantly reduced burst release and enhanced lasting antibacterial properties. The nanoarray capsules still preserved integrity with a little degradation after 2 days. The strategy described herein provides a versatile route for designing targeted drug delivery systems in orthopaedical and other biomedical fields

Micro-/nano-topography of selective laser melting titanium enhances adhesion and proliferation and regulates adhesion-related gene expressions of human gingival fibroblasts and human gingival epithelial cells

Background: Selective laser melting (SLM) titanium is an ideal option to manufacture customized implants with suitable surface modification to improve its bioactivity. The peri-implant soft tissues form a protective tissue barrier for the underlying osseointegration. Therefore, original microrough SLM surfaces should be treated for favorable attachment of surrounding soft tissues. Material and methods: In this study, anodic oxidation (AO) was applied on the microrough SLM titanium substrate to form TiO2 nanotube arrays. After that, calcium phosphate (CaP) nanoparticles were embedded into the nanotubes or the interval of nanotubes by electrochemical deposition (AOC). These two samples were compared to untreated (SLM) samples and accepted mechanically polished (MP) SLM titanium samples. Scanning electron microscopy, energy dispersive spectrometry, X-ray diffraction, surface roughness, and water contact angle measurements were used for surface characterization. The primary human gingival epithelial cells (HGECs) and human gingival fibroblasts (HGFs) were cultured for cell assays to determine adhesion, proliferation, and adhesion-related gene expressions. Results: For HGECs, AOC samples showed significantly higher adhesion, proliferation, and adhesion-related gene expressions than AO and SLM samples (P&lt;0.05) and similar exceptional ability in above aspects to MP samples. At the same time, AOC samples showed the highest adhesion, proliferation, and adhesion-related gene expressions for HGFs (P&lt;0.05). Conclusion: By comparison between each sample, we could confirm that both anodic oxidation and CaP nanoparticles had improved bioactivity, and their combined utilization may likely be superior to mechanical polishing, which is most commonly used and widely accepted. Our results indicated that creating appropriate micro-/nano-topographies can be an effective method to affect cell behavior and increase the stability of the peri-implant mucosal barrier on SLM titanium surfaces, which contributes to its application in dental and other biomedical implants

Enhanced Biocompatibility and Antibacterial Activity of Selective Laser Melting Titanium with Zinc-Doped Micro-Nano Topography

Selective laser melting (SLM) titanium is a suitable material for use in customized implants. However, long-term implant survival requires both successful osseointegration and promising antibacterial characteristics. Native SLM titanium thus requires proper modifications to improve its bioactivity and antibacterial efficacy. Micro-arc oxidation (MAO) was conducted on sandblasted SLM substrate to form a microporous TiO2 coating. Subsequently, hydrothermal treatment was applied to fabricate micro-nano zinc-incorporated coatings with different Zn content (1mM-Zn and 100M-Zn). Surface characterization was performed using scanning electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction, a three-dimensional profilometer, and a contact angle measuring device. The osteoblast-like cell line MC3T3-E1, Subclone 14, was used in cell viability assays to evaluate adhesion, proliferation, and ALP activity. An antibacterial assay was conducted using Streptococcus sanguinis and Fusobacterium nucleatum. Zn-incorporated samples exhibited higher adhesion, proliferation, and differentiation than did SLM and MAO samples. 100M Zn samples exhibited the highest proliferation, and 1mM-Zn samples manifested the highest ALP activity. In addition, Zn-incorporated samples exerted inhibitory effects on both Streptococcus sanguinis and Fusobacterium nucleatum. Combining micro-arc oxidation and hydrothermal treatment, we successfully fabricated a novel Zn-incorporated coating on a microporous SLM surface which possesses both outstanding bioactivity and antibacterial efficacy

DataSheet_1_Genome-wide association study of SNP- and gene-based approaches to identify susceptibility candidates for lupus nephritis in the Han Chinese population.pdf

BackgroundLupus nephritis (LN) is one of the most common and serious complications of systemic lupus erythaematosus (SLE). Genetic factors play important roles in the pathogenesis of LN and could be used to predict who might develop LN. The purpose of this study was to screen for susceptible candidates of LN across the whole genome in the Han Chinese population.Methods592 LN patients and 453 SLE patients without renal damage were genotyped at 492,970 single nucleotide polymorphisms (SNPs) in the genome-wide association study (GWAS). Fifty-six SNPs were selected for replication in an independent cohort of 188 LN and 171 SLE without LN patients. Further quantitative real-time (qRT) PCR was carried out in 6 LN patients and 6 healthy controls. Gene-based analysis was conducted using the versatile gene-based test for GWAS. Subsequently, enrichment and pathway analyses were performed in the DAVID database.ResultsThe GWAS analysis and the following replication research identified 9 SNPs showing suggestive correlation with LN (P-4). The most significant SNP was rs12606116 (18p11.32), at P=8.72×10−6. The qRT-PCR results verified the mRNA levels of LINC00470 and ADCYAP1, the closest genes to rs12606116, were significantly lower in LN patients. From the gene-based analysis, 690 genes had suggestive evidence of association (PConclusionsOur analyses identified several promising susceptibility candidates involved in LN, and further verification of these candidates was necessary.</p