Editorial

4 pages, 218 KiB

Open AccessEditorial

Special Issue: Bioceramics, Bioglasses, and Gels for Tissue Engineering

by Arish Dasan and Ashokraja Chandrasekar

Gels 2023, 9(7), 586; https://doi.org/10.3390/gels9070586 - 21 Jul 2023

Cited by 1 | Viewed by 884

Undoubtedly, biomaterials such as bioceramics, bioactive glasses, and gels have attracted a wide range of research interest in the field of tissue engineering (TE), as they facilitate the essential support and environment for cells to grow, differentiate, and, specifically, regenerate new tissues [...] [...] Read more.

Undoubtedly, biomaterials such as bioceramics, bioactive glasses, and gels have attracted a wide range of research interest in the field of tissue engineering (TE), as they facilitate the essential support and environment for cells to grow, differentiate, and, specifically, regenerate new tissues [...] Full article

(This article belongs to the Special Issue Bioceramics, Bioglasses and Gels for Tissue Engineering)

Research

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23 pages, 7829 KiB

Open AccessArticle

Curative Effects of Copper Iodide Embedded on Gallic Acid Incorporated in a Poly(vinyl alcohol) (PVA) Liquid Bandage

by Putita Phetcharat, Pakakrong Sangsanoh, Chasuda Choipang, Sonthaya Chaiarwut, Orawan Suwantong, Piyachat Chuysinuan and Pitt Supaphol

Gels 2023, 9(1), 53; https://doi.org/10.3390/gels9010053 - 08 Jan 2023

Cited by 4 | Viewed by 1956

Abstract

In daily life, people are often receiving minor cuts due to carelessness, leaving wounds on the skin. If wound healing is interrupted and the healing process does not finish, pathogens can easily enter wounds and cause infection. Liquid bandages are a fast and [...] Read more.

In daily life, people are often receiving minor cuts due to carelessness, leaving wounds on the skin. If wound healing is interrupted and the healing process does not finish, pathogens can easily enter wounds and cause infection. Liquid bandages are a fast and convenient way to help stop the bleeding of superficial wounds. Moreover, antibacterial agents in liquid bandages can promote wound restoration and fight bacteria. Herein, a poly(vinyl alcohol) (PVA) liquid bandage incorporating copper iodide nanoparticles (CuI NPs) was developed. CuI NPs were synthesized through green synthesis using gallic acid (GA) as a reducing and capping agent. The sizes of the CuI NPs, which were dependent on the concentration of GA, were 41.45, 43.51 and 49.71 nm, with the concentrations of gallic acid being 0, 2.5 mM and 5.0 mM, respectively. CuI NPs were analyzed using FTIR, XRD and SEM and tested for peroxidase-like properties and antibacterial activity. Then, PVA liquid bandages were formulated with different concentrations of stock CuI suspension. The results revealed that PVA liquid bandages incorporating 0.190% CuI synthesized with 5.0 mM of GA can kill bacteria within 24 h and have no harmful effects on human fibroblast cells. Full article

(This article belongs to the Special Issue Bioceramics, Bioglasses and Gels for Tissue Engineering)

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23 pages, 5192 KiB

Open AccessArticle

Robocasting and Laser Micromachining of Sol-Gel Derived 3D Silica/Gelatin/β-TCP Scaffolds for Bone Tissue Regeneration

by María V. Reyes-Peces, Eduardo Félix, Francisco J. Martínez-Vázquez, Rafael Fernández-Montesinos, Óscar Bomati-Miguel, María del Mar Mesa-Díaz, Rodrigo Alcántara, José Ignacio Vilches-Pérez, Mercedes Salido, Nicolás De la Rosa-Fox and Manuel Piñero

Gels 2022, 8(10), 634; https://doi.org/10.3390/gels8100634 - 07 Oct 2022

Cited by 2 | Viewed by 1983

Abstract

The design and synthesis of sol-gel silica-based hybrid materials and composites offer significant benefits to obtain innovative biomaterials with controlled porosity at the nanostructure level for applications in bone tissue engineering. In this work, the combination of robocasting with sol-gel ink of suitable [...] Read more.

The design and synthesis of sol-gel silica-based hybrid materials and composites offer significant benefits to obtain innovative biomaterials with controlled porosity at the nanostructure level for applications in bone tissue engineering. In this work, the combination of robocasting with sol-gel ink of suitable viscosity prepared by mixing tetraethoxysilane (TEOS), gelatin and β-tricalcium phosphate (β-TCP) allowed for the manufacture of 3D scaffolds consisting of a 3D square mesh of interpenetrating rods, with macropore size of 354.0 ± 17.0 μm, without the use of chemical additives at room temperature. The silica/gelatin/β-TCP system underwent irreversible gelation, and the resulting gels were also used to fabricate different 3D structures by means of an alternative scaffolding method, involving high-resolution laser micromachining by laser ablation. By this way, 3D scaffolds made of 2 mm thick rectangular prisms presenting a parallel macropore system drilled through the whole thickness and consisting of laser micromachined holes of 350.8 ± 16.6-micrometer diameter, whose centers were spaced 1312.0 ± 23.0 μm, were created. Both sol-gel based 3D scaffold configurations combined compressive strength in the range of 2–3 MPa and the biocompatibility of the hybrid material. In addition, the observed Si, Ca and P biodegradation provided a suitable microenvironment with significant focal adhesion development, maturation and also enhanced in vitro cell growth. In conclusion, this work successfully confirmed the feasibility of both strategies for the fabrication of new sol-gel-based hybrid scaffolds with osteoconductive properties. Full article

(This article belongs to the Special Issue Bioceramics, Bioglasses and Gels for Tissue Engineering)

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16 pages, 5071 KiB

Open AccessArticle

Processing of Calcium Magnesium Silicates by the Sol–Gel Route

by Andrada-Elena Alecu, Claudiu-Constantin Costea, Vasile-Adrian Surdu, Georgeta Voicu, Sorin-Ion Jinga and Cristina Busuioc

Gels 2022, 8(9), 574; https://doi.org/10.3390/gels8090574 - 09 Sep 2022

Cited by 9 | Viewed by 1899

Abstract

In this work, calcium magnesium silicate ceramics were processed through the sol–gel method in order to study the crystalline and morphological properties of the resulting materials in correlation with the compositional and thermal parameters. Tetraethyl orthosilicate and calcium/magnesium nitrates were employed as sources [...] Read more.

In this work, calcium magnesium silicate ceramics were processed through the sol–gel method in order to study the crystalline and morphological properties of the resulting materials in correlation with the compositional and thermal parameters. Tetraethyl orthosilicate and calcium/magnesium nitrates were employed as sources of cations, in ratios specific to diopside, akermanite and merwinite; they were further subjected to gelation, calcination (600 °C) and thermal treatments at different temperatures (800, 1000 and 1300 °C). The properties of the intermediate and final materials were investigated by thermal analysis, scanning electron microscopy, energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction and Rietveld refinement. Such ceramics represent suitable candidates for tissue engineering applications that require porosity and bioactivity. Full article

(This article belongs to the Special Issue Bioceramics, Bioglasses and Gels for Tissue Engineering)

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18 pages, 3981 KiB

Open AccessArticle

Gelatin Nanoparticles for Targeted Dual Drug Release out of Alginate-di-Aldehyde-Gelatin Gels

by Sophie Schrade, Lucas Ritschl, Regine Süss, Pia Schilling and Michael Seidenstuecker

Gels 2022, 8(6), 365; https://doi.org/10.3390/gels8060365 - 08 Jun 2022

Cited by 7 | Viewed by 2271

Abstract

The aim of the present work was to develop a dual staged drug release of an antibiotic (clindamycin) and a growth factor: bone morphogenetic protein-2 (BMP-2) from a biodegradable system consisting of hydrogel and gelatin nanoparticles (GNP). Two-step de-solvation allowed us to prepare [...] Read more.

The aim of the present work was to develop a dual staged drug release of an antibiotic (clindamycin) and a growth factor: bone morphogenetic protein-2 (BMP-2) from a biodegradable system consisting of hydrogel and gelatin nanoparticles (GNP). Two-step de-solvation allowed us to prepare GNPs (~100 nm) as drug carriers. Fluorescein isothiocyanate (FITC)-conjugated protein A was used as a model substance for BMP-2. A 28-day release experiment was performed to determine the release kinetics from GNP for both FITC-protein A and BMP-2, and for clindamycin (CLI) from the hydrogel. The size, structure, and overall morphology of GNP samples (empty, loaded with FITC-protein A and BMP-2) were examined using an environmental scanning electron microscope (ESEM). Cell culture assays (Live/dead; cell proliferation; cytotoxicity) were performed with MG-63 cells and BMP-2-loaded GNPs. Drug release experiments using clindamycin-loaded alginate-di-aldehyde (ADA) gelatin gels containing the drug-loaded GNPs were performed for 28 days. The resulting GNPs showed an empty size of 117 ± 29 nm, 176 ± 15 nm and 216 ± 36 nm when containing 2% FITC-protein A and 1% BMP-2, respectively. No negative effects of BMP-2-loaded GNPs on MG-63 cells were observed in live/dead staining. In the proliferation assay, an increase in cell proliferation was observed for both GNPs (GNP + BMP-2 and controls). The cytotoxicity assay continuously showed very low cytotoxicity for GNPs (empty; loaded). Clindamycin release showed a concentration of 25-fold higher than the minimum inhibitory concentration (MIC) against Staphylococcus aureus throughout the 28 day period. BMP-2 showed a reduced burst release and a steady release (~2 µg/mL) over a 28 day period. Full article

(This article belongs to the Special Issue Bioceramics, Bioglasses and Gels for Tissue Engineering)

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14 pages, 4033 KiB

Open AccessArticle

Influence of Ceria Addition on Crystallization Behavior and Properties of Mesoporous Bioactive Glasses in the SiO₂–CaO–P₂O₅–CeO₂ System

by Elena Maria Anghel, Simona Petrescu, Oana Catalina Mocioiu, Jeanina Pandele Cusu and Irina Atkinson

Gels 2022, 8(6), 344; https://doi.org/10.3390/gels8060344 - 31 May 2022

Cited by 5 | Viewed by 1689

Abstract

Knowledge of the crystallization stability of bioactive glasses (BGs) is a key factor in developing porous scaffolds for hard tissue engineering. Thus, the crystallization behavior of three mesoporous bioactive glasses (MBGs) in the 70SiO₂-(26-x)CaO-4P₂O₅-xCeO₂ system (x [...] Read more.

Knowledge of the crystallization stability of bioactive glasses (BGs) is a key factor in developing porous scaffolds for hard tissue engineering. Thus, the crystallization behavior of three mesoporous bioactive glasses (MBGs) in the 70SiO₂-(26-x)CaO-4P₂O₅-xCeO₂ system (x stands for 0, 1 and 5 mol. %, namely MBG(0/1/5)Ce), prepared using the sol–gel method coupled with the evaporation-induced self-assembly method (EISA), was studied. A thermal analysis of the multiple-component crystallization exotherms from the DSC scans was performed using the Kissinger method. The main crystalline phases of Ca₅(PO₄)2.823(CO₃)_0.22O, CaSiO₃ and CeO₂ were confirmed to be generated by the devitrification of the MBG with 5% CeO₂, MBG5Ce. Increasing the ceria content triggered a reduction in the first crystallization temperature while ceria segregation took place. The amount of segregated ceria of the annealed MBG5Ce decreased as the annealing temperature increased. The optimum processing temperature range to avoid the crystallization of the MBG(0/1/5)Ce powders was established. Full article

(This article belongs to the Special Issue Bioceramics, Bioglasses and Gels for Tissue Engineering)

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14 pages, 3719 KiB

Open AccessArticle

Photodynamic Therapy with Natural Photosensitizers in the Management of Periodontal Disease Induced in Rats

by Laura Monica Dascalu (Rusu), Marioara Moldovan, Codruta Sarosi, Sorina Sava, Alexandra Dreanca, Calin Repciuc, Robert Purdoiu, Andras Nagy, Mîndra Eugenia Badea, Ariadna Georgiana Paun, Iulia Clara Badea and Radu Chifor

Gels 2022, 8(2), 134; https://doi.org/10.3390/gels8020134 - 20 Feb 2022

Cited by 8 | Viewed by 2226

Abstract

This study aims to investigate the effect of new natural photosensitizers (PS) (based on oregano essential oil, curcuma extract, and arnica oil) through in vitro cytotoxicity and biological tests in rat-induced periodontal disease, treated with photodynamic therapy (aPDT). The cytotoxicity of PS was [...] Read more.

This study aims to investigate the effect of new natural photosensitizers (PS) (based on oregano essential oil, curcuma extract, and arnica oil) through in vitro cytotoxicity and biological tests in rat-induced periodontal disease, treated with photodynamic therapy (aPDT). The cytotoxicity of PS was performed on human dental pulp mesenchymal stem cells (dMSCs) and human keratinocyte (HaCaT) cell lines. Periodontal disease was induced by ligation of the first mandibular molar of 25 rats, which were divided into 5 groups: control group, periodontitis group, Curcuma and aPDT-treated group, oregano and aPDT-treated group, and aPDT group. The animals were euthanized after 4 weeks of study. Computed tomography imaging has been used to evaluate alveolar bone loss. Hematological and histological evaluation showed a greater magnitude of the inflammatory response and severe destruction of the periodontal ligaments in the untreated group.. For the group with the induced periodontitis and treated with natural photosensitizers, the aPDT improved the results; this therapy could be an important adjuvant treatment. The obtained results of these preliminary studies encourage us to continue the research of periodontitis treated with natural photosensitizers activated by photodynamic therapy. Full article

(This article belongs to the Special Issue Bioceramics, Bioglasses and Gels for Tissue Engineering)

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26 pages, 8051 KiB

Open AccessArticle

Regenerative Activities of ROS-Modulating Trace Metals in Subcutaneously Implanted Biodegradable Cryogel

by Abdulla A. Yergeshov, Mohamed Zoughaib, Rezeda A. Ishkaeva, Irina N. Savina and Timur I. Abdullin

Gels 2022, 8(2), 118; https://doi.org/10.3390/gels8020118 - 14 Feb 2022

Cited by 5 | Viewed by 2730

Abstract

Divalent trace metals (TM), especially copper (Cu), cobalt (Co) and zinc (Zn), are recognized as essential microelements for tissue homeostasis and regeneration. To achieve a balance between therapeutic activity and safety of administered TMs, effective gel formulations of TMs with elucidated regenerative mechanisms [...] Read more.

Divalent trace metals (TM), especially copper (Cu), cobalt (Co) and zinc (Zn), are recognized as essential microelements for tissue homeostasis and regeneration. To achieve a balance between therapeutic activity and safety of administered TMs, effective gel formulations of TMs with elucidated regenerative mechanisms are required. We studied in vitro and in vivo effects of biodegradable macroporous cryogels doped with Cu, Co or Zn in a controllable manner. The extracellular ROS generation by metal dopants was assessed and compared with the intracellular effect of soluble TMs. The stimulating ability of TMs in the cryogels for cell proliferation, differentiation and cytokine/growth factor biosynthesis was characterized using HSF and HUVEC primary human cells. Multiple responses of host tissues to the TM-doped cryogels upon subcutaneous implantation were characterized taking into account the rate of biodegradation, production of HIF-1α/matrix metalloproteinases and the appearance of immune cells. Cu and Zn dopants did not disturb the intact skin organization while inducing specific stimulating effects on different skin structures, including vasculature, whereas Co dopant caused a significant reorganization of skin layers, the appearance of multinucleated giant cells, along with intense angiogenesis in the dermis. The results specify and compare the prooxidant and regenerative potential of Cu, Co and Zn-doped biodegradable cryogels and are of particular interest for the development of advanced bioinductive hydrogel materials for controlling angiogenesis and soft tissue growth. Full article

(This article belongs to the Special Issue Bioceramics, Bioglasses and Gels for Tissue Engineering)

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14 pages, 4142 KiB

Open AccessArticle

Preparation and Biocompatibility of Poly Methyl Methacrylate (PMMA)-Mesoporous Bioactive Glass (MBG) Composite Scaffolds

by Irina Atkinson, Ana Maria Seciu-Grama, Oana Catalina Mocioiu, Ana Maria Mocioiu, Luminita Predoana, Mariana Voicescu, Jeanina Pandele Cusu, Ramona Marina Grigorescu, Rodica Mariana Ion and Oana Craciunescu

Gels 2021, 7(4), 180; https://doi.org/10.3390/gels7040180 - 23 Oct 2021

Cited by 8 | Viewed by 2860

Abstract

In recent years, the rising number of bone diseases which affect millions of people worldwide has led to an increased demand for materials with restoring and augmentation properties that can be used in therapies for bone pathologies. In this work, PMMA- MBG composite [...] Read more.

In recent years, the rising number of bone diseases which affect millions of people worldwide has led to an increased demand for materials with restoring and augmentation properties that can be used in therapies for bone pathologies. In this work, PMMA- MBG composite scaffolds containing ceria (0, 1, 3 mol%) were obtained by the phase separation method. The obtained composite scaffolds were characterized by X-ray diffraction, infrared spectroscopy, and scanning electron microscopy. UV–Vis measurement and EDX analysis confirmed the presence of cerium ions in the composite scaffolds. Evaluation of the in-vitro biocompatibility using MTT assay showed that composite scaffold containing 1 mol% of ceria presented higher viability than control cells (100%) for concentrations ranging between 5 and 50% after 96 h of incubation. Full article

(This article belongs to the Special Issue Bioceramics, Bioglasses and Gels for Tissue Engineering)

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Review

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16 pages, 733 KiB

Open AccessReview

Cryopreservation of Cell Sheets for Regenerative Therapy: Application of Vitrified Hydrogel Membranes

by Yoshitaka Miyamoto

Gels 2023, 9(4), 321; https://doi.org/10.3390/gels9040321 - 10 Apr 2023

Cited by 1 | Viewed by 2529

Abstract

Organ transplantation is the first and most effective treatment for missing or damaged tissues or organs. However, there is a need to establish an alternative treatment method for organ transplantation due to the shortage of donors and viral infections. Rheinwald and Green et [...] Read more.

Organ transplantation is the first and most effective treatment for missing or damaged tissues or organs. However, there is a need to establish an alternative treatment method for organ transplantation due to the shortage of donors and viral infections. Rheinwald and Green et al. established epidermal cell culture technology and successfully transplanted human-cultured skin into severely diseased patients. Eventually, artificial cell sheets of cultured skin were created, targeting various tissues and organs, including epithelial sheets, chondrocyte sheets, and myoblast cell sheets. These sheets have been successfully used for clinical applications. Extracellular matrix hydrogels (collagen, elastin, fibronectin, and laminin), thermoresponsive polymers, and vitrified hydrogel membranes have been used as scaffold materials to prepare cell sheets. Collagen is a major structural component of basement membranes and tissue scaffold proteins. Collagen hydrogel membranes (collagen vitrigel), created from collagen hydrogels through a vitrification process, are composed of high-density collagen fibers and are expected to be used as carriers for transplantation. In this review, the essential technologies for cell sheet implantation are described, including cell sheets, vitrified hydrogel membranes, and their cryopreservation applications in regenerative medicine. Full article

(This article belongs to the Special Issue Bioceramics, Bioglasses and Gels for Tissue Engineering)

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38 pages, 2712 KiB

Open AccessReview

Development of Scaffolds from Bio-Based Natural Materials for Tissue Regeneration Applications: A Review

by Murugiah Krishani, Wong Yen Shin, Hazwani Suhaimi and Nonni Soraya Sambudi

Gels 2023, 9(2), 100; https://doi.org/10.3390/gels9020100 - 23 Jan 2023

Cited by 34 | Viewed by 5975

Abstract

Tissue damage and organ failure are major problems that many people face worldwide. Most of them benefit from treatment related to modern technology’s tissue regeneration process. Tissue engineering is one of the booming fields widely used to replace damaged tissue. Scaffold is a [...] Read more.

Tissue damage and organ failure are major problems that many people face worldwide. Most of them benefit from treatment related to modern technology’s tissue regeneration process. Tissue engineering is one of the booming fields widely used to replace damaged tissue. Scaffold is a base material in which cells and growth factors are embedded to construct a substitute tissue. Various materials have been used to develop scaffolds. Bio-based natural materials are biocompatible, safe, and do not release toxic compounds during biodegradation. Therefore, it is highly recommendable to fabricate scaffolds using such materials. To date, there have been no singular materials that fulfill all the features of the scaffold. Hence, combining two or more materials is encouraged to obtain the desired characteristics. To design a reliable scaffold by combining different materials, there is a need to choose a good fabrication technique. In this review article, the bio-based natural materials and fine fabrication techniques that are currently used in developing scaffolds for tissue regeneration applications, along with the number of articles published on each material, are briefly discussed. It is envisaged to gain explicit knowledge of developing scaffolds from bio-based natural materials for tissue regeneration applications. Full article

(This article belongs to the Special Issue Bioceramics, Bioglasses and Gels for Tissue Engineering)

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20 pages, 865 KiB

Open AccessReview

Nanoparticle-Containing Wound Dressing: Antimicrobial and Healing Effects

by Pavel Yudaev, Yaroslav Mezhuev and Evgeniy Chistyakov

Gels 2022, 8(6), 329; https://doi.org/10.3390/gels8060329 - 24 May 2022

Cited by 28 | Viewed by 5613

Abstract

The dressings containing nanoparticles of metals and metal oxides are promising types of materials for wound repair. In such dressings, biocompatible and nontoxic hydrophilic polymers are used as a matrix. In the present review, we take a look at the anti-microbial effect of [...] Read more.

The dressings containing nanoparticles of metals and metal oxides are promising types of materials for wound repair. In such dressings, biocompatible and nontoxic hydrophilic polymers are used as a matrix. In the present review, we take a look at the anti-microbial effect of the nanoparticle-modified wound dressings against various microorganisms and evaluate their healing action. A detailed analysis of 31 sources published in 2021 and 2022 was performed. Furthermore, a trend for development of modern antibacterial wound-healing nanomaterials was shown as exemplified in publications starting from 2018. The review may be helpful for researchers working in the areas of biotechnology, medicine, epidemiology, material science and other fields aimed at the improvement of the quality of life. Full article

(This article belongs to the Special Issue Bioceramics, Bioglasses and Gels for Tissue Engineering)

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35 pages, 4013 KiB

Open AccessEditor’s ChoiceReview

Recent Advancements in Materials and Coatings for Biomedical Implants

by Kamalan Kirubaharan Amirtharaj Mosas, Ashok Raja Chandrasekar, Arish Dasan, Amirhossein Pakseresht and Dušan Galusek

Gels 2022, 8(5), 323; https://doi.org/10.3390/gels8050323 - 21 May 2022

Cited by 48 | Viewed by 6806

Abstract

Metallic materials such as stainless steel (SS), titanium (Ti), magnesium (Mg) alloys, and cobalt-chromium (Co-Cr) alloys are widely used as biomaterials for implant applications. Metallic implants sometimes fail in surgeries due to inadequate biocompatibility, faster degradation rate (Mg-based alloys), inflammatory response, infections, inertness [...] Read more.

Metallic materials such as stainless steel (SS), titanium (Ti), magnesium (Mg) alloys, and cobalt-chromium (Co-Cr) alloys are widely used as biomaterials for implant applications. Metallic implants sometimes fail in surgeries due to inadequate biocompatibility, faster degradation rate (Mg-based alloys), inflammatory response, infections, inertness (SS, Ti, and Co-Cr alloys), lower corrosion resistance, elastic modulus mismatch, excessive wear, and shielding stress. Therefore, to address this problem, it is necessary to develop a method to improve the biofunctionalization of metallic implant surfaces by changing the materials’ surface and morphology without altering the mechanical properties of metallic implants. Among various methods, surface modification on metallic surfaces by applying coatings is an effective way to improve implant material performance. In this review, we discuss the recent developments in ceramics, polymers, and metallic materials used for implant applications. Their biocompatibility is also discussed. The recent trends in coatings for biomedical implants, applications, and their future directions were also discussed in detail. Full article

(This article belongs to the Special Issue Bioceramics, Bioglasses and Gels for Tissue Engineering)

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