The Application of Fluoride in Dental Caries

The most efficient way to prevent caries is by using fluoridated dental products. Fluoride can reduce enamel demineralization and promote enamel remineralization. In terms of prevention, the topical application of fluoride is accessible, which includes fluoride toothpaste, fluoride varnish, fluoride gel, and mouth rinse. Besides, the application of fluoride is systematical. In some countries, fluoride is added into water, salt, or milk. Fluoride is also used for the medical treatment of early dental caries. However, fluoride is a double-edged sword. Excessive fluoride intake will cause toxic reactions, and dental fluorosis is caused by a high intake of fluorides during tooth development

Preparation and Characterization of Chitosan/β-Glycerophosphate Thermal-Sensitive Hydrogel Reinforced by Graphene Oxide

Thermal-sensitive hydrogel based on chitosan (CS) and β-glycerophosphate (GP) has shown good biocompatibility and biodegradability. But the application of such hydrogel is limited due to its poor mechanical property. Recently, graphene oxide(GO) is widely used as a reinforcement agent to prepare nanocomposites with different polymers for improving the properties of the materials. In this study, CS/GP-based hydrogels with different weight ratio of GO/CS (0.5, 1, 2%) were fabricated. The gelation time of the hydrogels at body temperature was evaluated by tube inverting method. The gelation process during heating was monitored by rheological measurement. The morphology, porosities, chemical structure, swelling properties of the lyophilized hydrogels were investigated by scanning electron microscopy, liquid displacement method, Fourier transform infrared spectroscopy and gravimetric method. Mechanical property of the hydrogels was analyzed by rheological measurement and unconfined compression test. MC3T3-E1 mouse pre-osteoblast cell line was used to assess the biological properties of the hydrogels. The results obtained from those assessments revealed that the addition of GO into CS/GP improved the properties of the prepared hydrogels without changing the high porous and interconnected microstructure and swelling ability of the hydrogels. The gelation time at body temperature was significantly reduced by nearly 20% with the addition of small amount of GO (0.5% weight ratio of CS). The mechanical properties of the hydrogels containing GO were improved significantly over that of CS/GP. The storage (G′)/loss (G″) moduli of the hydrogels with GO were 1.12 to 1.69 times that of CS/GP at the gelling temperature. The Young's modulus of 0.5%GO/CS/GP hydrogel is 1.76 times that of CS/GP. Moreover, the 0.5%GO/CS/GP hydrogel revealed remarkable biological affinity such as cellular attachment, viability and proliferation. All of these results suggest that 0.5%GO/CS/GP hydrogel has great potential for practical application in biomedical field

Graphene Family Materials in Bone Tissue Regeneration: Perspectives and Challenges

Abstract We have witnessed abundant breakthroughs in research on the bio-applications of graphene family materials in current years. Owing to their nanoscale size, large specific surface area, photoluminescence properties, and antibacterial activity, graphene family materials possess huge potential for bone tissue engineering, drug/gene delivery, and biological sensing/imaging applications. In this review, we retrospect recent progress and achievements in graphene research, as well as critically analyze and discuss the bio-safety and feasibility of various biomedical applications of graphene family materials for bone tissue regeneration

Health benefit application of functional oligosaccharides

There is no doubt that the functional oligosaccharides have positive effects on human health, both in the prevention and in treatment of chronic diseases. Therefore, there is great interest in health benefits of the functional oligosaccharides. The functional oligosaccharides of various origins (viruses, bacteria, plants and fungi) have been used extensively both as pharmacological supplements, food ingredients, in processed food to aid weight control, to regulation of glucose control for diabetic patients and reducing serum lipid levels in hyperlipidemics and other some acute and chronic diseases. Keeping in view, the pharmacological importance of the functional oligosaccharides and its derivatives, this article discusses the potential of the functional oligosaccharides to modulate the gut flora, to affect different gastrointestinal activities and lipid metabolism, to enhance immunity, and to reduce diabetes, obesity and cardiovascular risk for further exploitation of health benefits of the functional oligosaccharides

Influence of adhesion on the color of glass infiltrated alumina ceramic restorations

Objective: To investigate the effects of luting agent on the final color of glass infiltrated alumina ceramic restorations. \ud \ud Methods: 12 plate-shaped specimens with 12.5 mm in diameter and 0.5 mm thickness were fabri-cated from GI-II(color IG2). Vitadur alpha veneering porcelain(color A2) with 1.0 mm thickness was fired to GI-Ⅱglass/alumina composite. 12 plate-shaped background specimens simulating the metal alloy post-and-core 12.5 mm in diameter and 2 mm thickness were also made from Ni-Cr alloy. All-ceramic specimens were luted to the metal alloy by Zinc Phosphate cement, glass ionomer cement and composite resin. The color shifts of the specimens were measured by colorimeter. \ud \ud Results: Luting agents had effect on the final color of restorations. The influence of composite resin was least, followed by glass ionomer cement and Zinc Phosphate cement. The color difference between with and without Zinc Phosphate cement could be identified by the eye. \ud \ud Conclusion: To reduce the effect of luting agents, composite resin is recommended to all-ceramic restorations' adhesion

The Application of Zirconia in Tooth Defects

Dental caries is among the most prevalent chronic diseases of childhood, affecting larger part of children and adults. Non-treated enamel caries can lead to destruction and then spreads into the underlying softer and sensitive dentine layer. Dental restorative materials are applied to treat and reconstruct damaged teeth clinically and recover their functions. Currently, there are various dental restorative materials available, and many appropriate materials are used to restore dental carious teeth. The applicability of biomimetic principles can elicit innovations in restorative dentistry for tooth conservation and preservation. There are three types of materials commonly used in dental restorations: resin, alloys, and ceramic. During the past decade, zirconia-based ceramics have been successfully introduced into the clinic due to acceptable biocompatibility, lower price compared with gold restorations, and better appearance than traditional metal-ceramic restorations. Recently, zirconia restoration is an acceptable treatment option in restorative dentistry and a developing trend in esthetic dentistry

Construction of Helically Oriented Syndiotactic Polypropylene/Isotactic Polypropylene Composites for Medical Interventional Tubes <i>via</i> Rotation Extrusion

Medical tubes are important medical devices for interventional therapy. However, current tubes suffer from poor biocompatibility due to the heterogeneity of composites. In this study, we demonstrated a syndiotactic polypropylene (sPP)/isotactic polypropylene (iPP) composite tube with reinforced hoop strength and considerable biocompatibility. Taking advantage of the same backbone structure of PP, an iPP network was constructed in situ by rotation extrusion technology, which not only promoted interfacial crystallization but also increased the orientation degree in the hoop direction. As a result, the modulus of the iPP fiber-reinforced tubes reached 4.28 MPa/rad, which is about three times than that of the sPP tube. The biocompatibility of the as-prepared tube was evaluated in vitro and in vivo, and sPP/iPP had no impact on the cell shape or proliferation. This work overcomes the current bottleneck of a lack of composite materials for medical interventional tubes and simultaneously broadens the application of the sPP matrix

Enhanced Osseointegration of Porous Titanium Modified with Zeolitic Imidazolate Framework‑8

Nanoscale zeolitic imidazolate framework-8 (ZIF-8)-modified titanium (ZIF-8@AHT) can enhance osteogenesis in vitro. In this study, we systematically and quantitatively examined the effects of ZIF-8@AHT on osteogenesis, and investigated its ability to form bone in vivo. First, we coated various quantities of nanoscale ZIF-8 crystals on alkali- and heat-treated titanium (AHT) by controlling the concentration of the synthesis solution. We then characterized the ZIF-8@AHT materials using scanning electron microscopy (SEM), powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and determination of the sessile drop contact angle. To illustrate the combined effects of micro/nanotopography and ZIF-8@AHT composition on bone regeneration, we cultured MC3T3-E1 preosteoblast cells on various titanium substrates in vitro by setting pure titanium (Ti) and AHT as control groups. The ZIF-8@AHTs enhanced cell bioactivity compared with AHT and Ti, as evidenced by increased extracellular matrix (ECM) mineralization, collagen secretion and the upregulated expression of osteogenic genes (<i>Alp</i>, <i>Col1</i>, <i>Opg</i>, and <i>Runx2</i>) and osteogenesis-related proteins (ALP and OPG). ZIF-8@AHT-1/8 exhibited better osteogenic activity compared with the other ZIF-8@AHT groups investigated. We subsequently inserted Ti, AHT, and ZIF-8@AHT-1/8 implants into the healed first molars (M1s) of mice, and found that ZIF-8@AHT-1/8 also promoted osseointegration at the bone–implant interface. These results suggest that ZIF-8@AHT-1/8 has great potential for practical application in implant modification

Enhanced Osseointegration of Porous Titanium Modified with Zeolitic Imidazolate Framework‑8

Nanoscale zeolitic imidazolate framework-8 (ZIF-8)-modified titanium (ZIF-8@AHT) can enhance osteogenesis in vitro. In this study, we systematically and quantitatively examined the effects of ZIF-8@AHT on osteogenesis, and investigated its ability to form bone in vivo. First, we coated various quantities of nanoscale ZIF-8 crystals on alkali- and heat-treated titanium (AHT) by controlling the concentration of the synthesis solution. We then characterized the ZIF-8@AHT materials using scanning electron microscopy (SEM), powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and determination of the sessile drop contact angle. To illustrate the combined effects of micro/nanotopography and ZIF-8@AHT composition on bone regeneration, we cultured MC3T3-E1 preosteoblast cells on various titanium substrates in vitro by setting pure titanium (Ti) and AHT as control groups. The ZIF-8@AHTs enhanced cell bioactivity compared with AHT and Ti, as evidenced by increased extracellular matrix (ECM) mineralization, collagen secretion and the upregulated expression of osteogenic genes (<i>Alp</i>, <i>Col1</i>, <i>Opg</i>, and <i>Runx2</i>) and osteogenesis-related proteins (ALP and OPG). ZIF-8@AHT-1/8 exhibited better osteogenic activity compared with the other ZIF-8@AHT groups investigated. We subsequently inserted Ti, AHT, and ZIF-8@AHT-1/8 implants into the healed first molars (M1s) of mice, and found that ZIF-8@AHT-1/8 also promoted osseointegration at the bone–implant interface. These results suggest that ZIF-8@AHT-1/8 has great potential for practical application in implant modification