BACKGROUND:Janus micro/nanoparticles are widely used in the field of tissue engineering,drug delivery,cancer therapy,bioimaging,and sensing due to their shape,structure,and functional anisotropy.OBJECTIVE:To elucidate the cutting-edge applications of Janus micro/nanoparticles in biomedicine.METHODS:Relevant literature published between 2010 and 2024 was retrieved from CNKI,WanFang Data,PubMed,and Web of Science databases.Searches were conducted using Chinese search terms"Janus nanoparticle,Janus particle,dual-faced particle,drug delivery,cancer therapy,bioimaging,biosensing,tissue engineering"and English search terms"Janus nanoparticle,Janus particle,drug delivery,cancer therapy,biosensing,bioimaging,tissue engineering."A total of 69 articles were selected for review after screening,organizing,summarizing,and synthesizing.RESULTS AND CONCLUSION:Janus micro/nanoparticles can be classified into three major categories based on their basic material properties:organic,inorganic,and organic-inorganic composites.Synthetic strategies consist of shielding,self-assembly,phase separation,microfluidics,and nucleation and growth techniques.Janus micro/nanoparticles exhibit high-efficiency drug delivery through characteristics such as high drug loading,gated release,and autonomous motion.In addition to enhancing traditional cancer treatment modalities(radiation and chemotherapy),Janus micro/nanoparticles can also be applied to emerging cancer treatment methods such as cell immunotherapy,protein drugs,and ferroptosis.Janus micro/nanoparticles serve as contrast agents to enhance bioimaging modalities(CT,MRI,and ultrasound)for high-quality imaging,guiding diagnosis and treatment.Janus micro/nanoparticles are utilized in tissue engineering for delivering growth factors,enhancing mechanical properties of biomaterials,and exhibiting antibacterial effects.Researchers have successfully tailored Janus micro/nanoparticles with desired functionalities by combining different organic polymers and inorganic materials using various synthetic strategies,enabling applications in complex biomedical fields.Despite current advancements,reports on the application of Janus micro/nanoparticles in tissue regeneration,large-scale production,and human clinical trials are relatively limited.Therefore,further research efforts are needed in the development,synthetic strategies,clinical safety assessment,and translation of such materials.

OBJECTIVES: This study aims to use 3D prin-ting technology based on the principle of stereo lithography apparatus (SLA) to shape dental lithium disilicate ceramics and study the effects of different slurry proportions on the microstructure and properties of heat-treated samples. METHODS: The experimental group comprised lithium disilicate ceramics manufactured through SLA 3D printing, and the control group comprised lithium disilicate ceramics (IPS e.max CAD) fabricated through commercial milling. An array of different particle sizes of lithium disilicate ceramic powder materials (nano and micron) was selected for mixing with photocurable acrylate resin. The proportion of experimental raw materials was adjusted to prepare five groups of ceramic slurries for 3D printing (Groups S1-S5) on the basis of rheological properties, stability, and other factors. Printing, debonding, and sintering were conducted on the experimental group with the optimal ratio, followed by measurements of microstructure, crystallographic information, shrinkage, and mechanical properties. RESULTS: Five groups of lithium disilicate ceramic slurries were prepared, of which two groups with high solid content (75%) (Groups S2 and S3) were selected for 3D printing. X-ray diffraction and scanning electron microscopy results showed that lithium disilicate was the main crystalline phase in Groups S2 and S3, and its microstructure was slender, uniform, and compact. The average grain sizes of Groups S2 and S3 were (559.79±84.58) nm and (388.26±61.49) nm, respectively (P<0.05). Energy spectroscopy revealed that the samples in the two groups contained a high proportion of Si and O elements. After heat treatment, the shrinkage rate of the two groups of ceramic samples was 18.00%-20.71%. Test results revealed no statistical difference in all mechanical properties between Groups S2 and S3 (P>0.05). The flexural strengths of Groups S2 and S3 were (231.79±21.71) MPa and (214.86±46.64) MPa, respectively, which were lower than that of the IPS e.max CAD group (P<0.05). The elasticity modulus of Groups S2 and S3 were (87.40±12.99) GPa and (92.87±19.76) GPa, respectively, which did not significantly differ from that of the IPS e.max CAD group (P>0.05). The Vickers hardness values of Groups S2 and S3 were (6.53±0.19) GPa and (6.25±0.12) GPa, respectively, which were higher than that of the IPS e.max CAD group (P<0.05). The fracture toughness values of Groups S2 and S3 were (1.57±0.28) MPa·m^0.5 and (1.38±0.17) MPa·m^0.5, respectively, which did not significantly differ from that of the IPS e.max CAD group (P>0.05). CONCLUSIONS The combination of lithium disilicate ceramic powders with different particle sizes can yield a slurry with high solid content (75%) and suitable viscosity and stability. The dental lithium disilicate ceramic material is successfully prepared by using 3D printing technology. The 3D-printed samples show a small shrinkage rate after heat treatment. Their microstructure conforms to the crystal phase of lithium disilicate ceramics, and their mechanical properties are close to those of milled lithium disilicate ceramics.
Printing, Three-Dimensional ; Dental Porcelain/chemistry* ; Ceramics/chemistry* ; Materials Testing ; Particle Size

BACKGROUND:Metal-organic framework is an emerging porous material composed of metal nodes and organic ligands.Metal-organic frameworks can be both intrinsic photodynamic or photothermal and modified by photothermal agents or photosensitizers.Upon light irradiation,phototherapy effects are exerted through production of reactive oxygen species or rise in temperature,which is widely applied to antitumor and antibacterial treatments.When metal-organic frameworks possess both of above phototherapeutic effects,they can exert a synergistic therapeutic effect to compensate for the shortcomings of using a single phototherapy method.OBJECTIVE:To summarize recent proposed photodynamic-thermal synergistic strategies according to different structures of metal-organic frameworks,to provide new insights into the structural design,functionalization,and clinical scenarios of combined therapy metal-organic frameworks.METHODS:Using"metal-organic frameworks,photodynamic therapy,photothermal therapy"as Chinese search terms and"metal-organic frameworks,photodynamic therapy,photothermal therapy,phototherapy"as English search terms,articles were searched on PubMed,Web of Science,ScienceDirect,CNKI,and WanFang databases.Finally,76 articles were included for review.RESULTS AND CONCLUSION:(1)The combination of photothermal and photodynamic therapy has been shown to exert a synergistic effect.(2)Current strategies for combined photothermal and photodynamic therapy predominantly involve the modifying of metal-organic frameworks to impart photothermal and photodynamic properties,encapsulating phototherapeutic agents within metal-organic frameworks,forming core-shell structures with phototherapeutic agents and metal-organic frameworks,in-situ reduction of phototherapeutic agents within metal-organic frameworks,adhering phototherapeutic agents to metal-organic framework surfaces,and unique modification methods like pyrolyzing metal-organic frameworks to form metal-organic frameworks-derived carbon materials.(3)To construct metal-organic framework structures for specific phototherapy,it is essential to comprehensively consider the type,size,and binding of the phototherapeutic agents and metal-organic frameworks,and select different synthesis strategies accordingly.Encapsulation is a straightforward synthesis approach but is only suitable for small-sized phototherapeutic agents.Core-shell structures are stable,but their synthesis process is relatively complex.In situ reduction does not impose special restrictions on the size of phototherapeutic agents,but it is challenging to precisely control the growth of the phototherapeutic agents within the metal-organic frameworks.Surface attachment offers a simple synthesis step,but it cannot prevent the early aggregation and quenching of phototherapeutic agents.Surface attachment requires stringent conditions and can only be implemented with specific metal-organic frameworks.(4)The existing photothermal and photodynamic combined therapy approaches have been primarily applied in antimicrobial and antitumor treatments,demonstrating remarkable efficacy.The specific applications are related to the properties of the phototherapeutic agents and metal-organic frameworks.A minority of applications extend to rheumatoid arthritis and anticoagulation thrombolysis treatments,indicating a broad potential application scope.(5)The clinical translation of photothermal and photosensitizing agents is currently in its nascent stage,facing key challenges that include the evaluation of biocompatibility and biosafety,optimization of laser irradiation parameters,and the development of efficient methods for large-scale synthesis.

BACKGROUND:Janus micro/nanoparticles are widely used in the field of tissue engineering,drug delivery,cancer therapy,bioimaging,and sensing due to their shape,structure,and functional anisotropy.OBJECTIVE:To elucidate the cutting-edge applications of Janus micro/nanoparticles in biomedicine.METHODS:Relevant literature published between 2010 and 2024 was retrieved from CNKI,WanFang Data,PubMed,and Web of Science databases.Searches were conducted using Chinese search terms"Janus nanoparticle,Janus particle,dual-faced particle,drug delivery,cancer therapy,bioimaging,biosensing,tissue engineering"and English search terms"Janus nanoparticle,Janus particle,drug delivery,cancer therapy,biosensing,bioimaging,tissue engineering."A total of 69 articles were selected for review after screening,organizing,summarizing,and synthesizing.RESULTS AND CONCLUSION:Janus micro/nanoparticles can be classified into three major categories based on their basic material properties:organic,inorganic,and organic-inorganic composites.Synthetic strategies consist of shielding,self-assembly,phase separation,microfluidics,and nucleation and growth techniques.Janus micro/nanoparticles exhibit high-efficiency drug delivery through characteristics such as high drug loading,gated release,and autonomous motion.In addition to enhancing traditional cancer treatment modalities(radiation and chemotherapy),Janus micro/nanoparticles can also be applied to emerging cancer treatment methods such as cell immunotherapy,protein drugs,and ferroptosis.Janus micro/nanoparticles serve as contrast agents to enhance bioimaging modalities(CT,MRI,and ultrasound)for high-quality imaging,guiding diagnosis and treatment.Janus micro/nanoparticles are utilized in tissue engineering for delivering growth factors,enhancing mechanical properties of biomaterials,and exhibiting antibacterial effects.Researchers have successfully tailored Janus micro/nanoparticles with desired functionalities by combining different organic polymers and inorganic materials using various synthetic strategies,enabling applications in complex biomedical fields.Despite current advancements,reports on the application of Janus micro/nanoparticles in tissue regeneration,large-scale production,and human clinical trials are relatively limited.Therefore,further research efforts are needed in the development,synthetic strategies,clinical safety assessment,and translation of such materials.

BACKGROUND:Metal-organic framework is an emerging porous material composed of metal nodes and organic ligands.Metal-organic frameworks can be both intrinsic photodynamic or photothermal and modified by photothermal agents or photosensitizers.Upon light irradiation,phototherapy effects are exerted through production of reactive oxygen species or rise in temperature,which is widely applied to antitumor and antibacterial treatments.When metal-organic frameworks possess both of above phototherapeutic effects,they can exert a synergistic therapeutic effect to compensate for the shortcomings of using a single phototherapy method.OBJECTIVE:To summarize recent proposed photodynamic-thermal synergistic strategies according to different structures of metal-organic frameworks,to provide new insights into the structural design,functionalization,and clinical scenarios of combined therapy metal-organic frameworks.METHODS:Using"metal-organic frameworks,photodynamic therapy,photothermal therapy"as Chinese search terms and"metal-organic frameworks,photodynamic therapy,photothermal therapy,phototherapy"as English search terms,articles were searched on PubMed,Web of Science,ScienceDirect,CNKI,and WanFang databases.Finally,76 articles were included for review.RESULTS AND CONCLUSION:(1)The combination of photothermal and photodynamic therapy has been shown to exert a synergistic effect.(2)Current strategies for combined photothermal and photodynamic therapy predominantly involve the modifying of metal-organic frameworks to impart photothermal and photodynamic properties,encapsulating phototherapeutic agents within metal-organic frameworks,forming core-shell structures with phototherapeutic agents and metal-organic frameworks,in-situ reduction of phototherapeutic agents within metal-organic frameworks,adhering phototherapeutic agents to metal-organic framework surfaces,and unique modification methods like pyrolyzing metal-organic frameworks to form metal-organic frameworks-derived carbon materials.(3)To construct metal-organic framework structures for specific phototherapy,it is essential to comprehensively consider the type,size,and binding of the phototherapeutic agents and metal-organic frameworks,and select different synthesis strategies accordingly.Encapsulation is a straightforward synthesis approach but is only suitable for small-sized phototherapeutic agents.Core-shell structures are stable,but their synthesis process is relatively complex.In situ reduction does not impose special restrictions on the size of phototherapeutic agents,but it is challenging to precisely control the growth of the phototherapeutic agents within the metal-organic frameworks.Surface attachment offers a simple synthesis step,but it cannot prevent the early aggregation and quenching of phototherapeutic agents.Surface attachment requires stringent conditions and can only be implemented with specific metal-organic frameworks.(4)The existing photothermal and photodynamic combined therapy approaches have been primarily applied in antimicrobial and antitumor treatments,demonstrating remarkable efficacy.The specific applications are related to the properties of the phototherapeutic agents and metal-organic frameworks.A minority of applications extend to rheumatoid arthritis and anticoagulation thrombolysis treatments,indicating a broad potential application scope.(5)The clinical translation of photothermal and photosensitizing agents is currently in its nascent stage,facing key challenges that include the evaluation of biocompatibility and biosafety,optimization of laser irradiation parameters,and the development of efficient methods for large-scale synthesis.

BACKGROUND:Bone is a remarkable natural material possessing piezoelectric properties.By harnessing the biomimetic piezoelectric effect,tissue engineering materials can be employed to effectively address bone tissue defects and facilitate their repair. OBJECTIVE:Using a solid-phase force chemistry technique,a piezoelectric scaffold with inherent osteogenic properties was meticulously fabricated.This unique scaffold was then assessed for its impact on osteoblast adhesion,proliferation,and osteogenic differentiation. METHODS:Polyvinylidene fluoride(PVDF)powders,along with commercially available NaCl(mass ratios are 60:40,50:50,40:60,and 30:70,respectively),were subjected to solid-phase shear milling technology,resulting in a homogenous mixture.Through a melting process,a substantial material was formed,and subsequent treatment with a pure water solution effectively eliminated the NaCl.Consequently,PVDF piezoelectric foam scaffolds with varying pore sizes were successfully prepared.These materials were categorized as PVDF-40,PVDF-50,PVDF-60,and PVDF-70,denoting the respective mass percentages of NaCl during preparation.The surface morphology,crystal phase composition,thermodynamic behavior,mechanical properties,and piezoelectric properties of each group were meticulously characterized.The four kinds of piezoelectric foam scaffolds were co-cultured with the MG63 osteoblast cell line to evaluate its biocompatibility and potential to promote bone differentiation. RESULTS AND CONCLUSION:(1)The scanning electron microscopy,four groups of scaffolds had multi-level pores.As the NaCl mass fraction in the mixed powder increased,the porosity of the scaffolds increased.X-ray energy dispersion spectrum,X-ray diffraction,Fourier transform infrared spectroscopy,and thermogravimetric analysis collectively revealed the scaffold predominantly comprised the α phase,which inherently lacked piezoelectric properties.However,the application of solid-phase force chemistry successfully stimulated the formation of the β phase,thereby enhancing the scaffold's piezoelectric properties.Notably,the PVDF-60 group exhibited the highest proportion of the β phase among all the tested groups.The results of cyclic compression testing and piezoelectric performance assessment demonstrated that the PVDF-60 group exhibited superior compressive strength and piezoelectric performance compared to the other groups.(2)The findings from scanning electron microscopy and laser confocal microscopy exhibited that MG63 cells adhered well to the surface of the four groups of scaffolds,with good morphology,extended more pseudopods,and secreted a large amount of extracellular matrix.CCK-8 assay revealed that the proliferative absorbance of PVDF-60 cells cultured for 4 days was higher than that of the other three groups(P<0.000 1).Alkaline phosphatase staining and alizarin red staining showed that the expression of alkaline phosphatase and the number of calcified nodules in the PVDF-60 group were higher than those in the other three groups(P<0.01,P<0.000 1).(3)The piezoelectric PVDF foam-based scaffolds demonstrated favorable cytocompatibility.Notably,the PVDF-60 group showed superior mechanical properties,piezoelectric performance,and bone-inducing capabilities.

The problems caused by proximal contact loss(PCL)of dental implants have been a mainstream research topic in recent years,and scholars are unanimously committed to analyzing their causes and related factors,aiming to identify solutions to the problems related to PCL.The effects of the anterior component of force(ACF),the lifelong re-molding of the adult craniofacial jaw and alveolar socket,and the osseointegration characteristics of dental implants are the main causes of PCL.On the one hand,the closing movement of the mandible causes the ACF of the tooth to move through the posterior molar cusp.Moreover,drifting between the upper and lower posterior teeth and mandibular anteri-or teeth can cause the anterior teeth of the upper and lower jaws to be displaced labially.On the other hand,reconstruc-tion of the jaw,alveolar socket and tooth root,the forward horizontal force of the masticatory muscles,the dynamic com-ponent of the jaw and the forward force generated by the oblique plane of the tooth cusp can cause the natural tooth to experience near-middle drift.Additionally,natural teeth can shift horizontally and vertically and rotate to accommodate remodeling of the stomatognathic system and maintain oral function.Nevertheless,the lack of a natural periodontal mem-brane during implant osseointegration,the lack of a physiological basis for near-medium drift,the small average degree of vertical motion and the integrated silence of dental implants without the overall drift characteristics of natural teeth increases the probability of PCL.The high incidence of PCL is clearly associated with the duration of prosthesis delivery and the mesial position;but it is also affected by the magnitude of the bite force,occlusion,the adjacent teeth,restora-tion design,implant location,jaw,and patient age and sex.PCL has shown a significant correlation with food impaction,but not a one-to-one correspondence,and did not meet the necessary and sufficient conditions.PCL is also associated with peri-implant lesions as well as dental caries.PCL prevention included informed consent,regular examinations,se-lection of retention options,point of contact enhancement,occlusal splints,and the application of multipurpose digital crowns.Management of the PCL includes adjacent contact point additions,orthodontic traction,and occlusal adjust-ment.Existing methods can solve the problem of food impaction in the short term with comprehensive intervention to seek stable,long-term effects.Symmetric and balanced considerations will expand the treatment of issues caused by PCL.

Pregnancy predisposes to various oral diseases,which can compromise the health of both the pregnant woman and the fe-tus.Management of these diseases often entails both local and systemic anti-infective treatments,which may involve complex medication practices.There is a prevalent concern among pregnant women regarding the potential effects of local anesthetics,antibiotics and other pharmacological agents on fetal health.Dentists should comprehend the drug indications and their safe usage boundaries to formulate ef-fective systematic strategies and clinical management protocols.The rational use of medications should not be precluded.Effective treat-ment should be administered to prevent adverse outcomes.This article reviews the safety of commonly used local and systemic oral med-ications during pregnancy and aims to offer appropriate therapeutic approaches for managing oral diseases in this population.

Continuing advances in dentin bonding technology and adhesives revolutionized bonding of resin-based composite restorations. However, hybrid layers created by contemporary dentin adhesives present imperfect durability, and degradation of collagen matrix by endogenous enzymes is a significant factor causing destruction of hybrid layers. Bond durability can be improved by using enzyme inhibitors to prevent collagen degradation and to preserve integrity of collagen matrix. This review summarizes progress on matrix metalloproteinase inhibitors (including chlorhexidine, ethylenediaminetetraacetic acid, quaternary ammonium salt, tetracycline and its derivatives, hydroxamic acid inhibitors, bisphosphonate derivative, and cross-linking agents) and suggests prospects for these compounds.
Acid Etching, Dental ; Bisphenol A-Glycidyl Methacrylate ; Collagen ; Dental Bonding ; Dentin ; Dentin-Bonding Agents ; Humans ; Matrix Metalloproteinase 2 ; Matrix Metalloproteinase Inhibitors

Dental educations in China and USA have different histories and systems even if they are similar in some respects.In this paper,by taking school of dental medicine in Harvard university as an example,dental educations in China and USA were compared with each other concerning the enrollment requirement,school system,course arrangement,teaching methods,clinical practice,elc.Based on the comparison,advices on how to improve and reform our dental education system were provided by learning from the advantages of dental education in USA.