Effect of sustained release of rhBMP-2 from dried and wet hyaluronic acid hydrogel carriers compared with direct dip coating of rhBMP-2 on peri-implant osteogenesis of dental implants in canine mandibles

Evaluation of Peri-Implant Bone Repair in Ovariectomized Rats Submitted to the Implant Placement Functionalized with Anti-Sclerostin

(1) Background: The challenges in Implantology involve the development of alternative methods to enhance bone repair in patients with systemic conditions, such as osteoporosis. This study aimed to evaluate the effect of a local anti-sclerostin monoclonal antibody (Scl-Ab) on the functionalization of titanium implant surfaces through a dip-coating technique in peri-implant bone repair. (2) Methods: A total of 32 female rats were separated into four groups (n = 8): SHAM NT (Sham surgery), OVX NT (ovariectomy), SHAM Scl-Ab (SHAM; implants functionalized with Scl-Ab), and OVX Scl-Ab (OVX; implants functionalized with Scl-Ab). Implant surgery was executed 30 days after ovariectomy, and the rats were euthanized 28 days postoperatively. The right tibia was used for removal torque and RT-PCR, while the left tibia was collected for micro-CT and laser confocal microscopy. (3) Results: Functionalization with Scl-Ab significantly increased the gene expression of bone markers, especially ALP, in the SHAM Scl-Ab group compared to the other groups (p < 0.05). (4) Conclusions: Some parameters of this study indicate that implants functionalized with anti-sclerostin bone anabolic drug enhance peri-implant bone repair, especially in healthy rats. However, more studies must be carried out to confirm the therapeutic benefits of this approach.

Osteogenic function of BMP2-modified PEEK scaffolds for orbital fracture repair

This study aimed to investigate the osteogenic function of polyetheretherketone (PEEK) scaffolds modified with bone morphogenetic protein 2 (BMP2) and its possibility for orbital fracture repair. The 3D-printed PEEK sheets were combined with BMP2-loaded hyaluronic acid hydrogel (HAH) to fabricate PEEK-BMP2-HAH composite scaffolds. Bone marrow mesenchymal stem cells (BMSCs) were seeded onto PEEK or PEEK-BMP2-HAH scaffolds. Cell adhesion and cell proliferation were measured by transmission electron microscopy and CCK-8 assay. Alkaline phosphatase (ALP) chromogenic, alizarine red S staining, and PCR analysis of Runt-related transcription factor 2 (Runx2), collagen-I (Col-I), Osterix, and osteopontin (OPN) were performed to assess osteogenic activity. The rat orbital fracture defect model is proposed for evaluating the biocompatibility, osteogenic integration, and functional recovery of PEEK orbital implants. Compared with PEEK, cell adhesion and cell proliferation were increased in PEEK-BMP2-HAH scaffolds. ALP activity and mineralized nodule formation were increased in PEEK-BMP2-HAH scaffolds than that in PEEK the mRNA expression of Runx2, Osterix, Col-I and OPN was increased on PEEK-BMP2-HAH scaffolds than that on PEEK at 14 d of osteogenic induction. Besides, a bone defect animal model revealed that BMP2-HAH-modified PEEK scaffolds could effectively facilitate the repair of the orbital bone defect, with increased expression of OPN and Runx2. BMP2-loaded HAH effectively increased adhesion, proliferation, and osteogenic differentiation of BMSCs on PEEK. PEEK-BMP2-HAH scaffolds are expected to become new materials for orbital fracture repair.

Is Hydrogel an Appropriate Bioadhesive Material for Sutureless Oral Wound Closure?

Background and Aims

An effective surgical adhesive must possess strength, biodegradability, flexibility, non-toxicity, and the ability to accommodate to tissue movement. However, existing adhesives in the market lack some of these crucial properties. Both synthetic cyanoacrylate and natural fibrin glue have been explored for sutureless oral surgery, but they come with specific limitations. This perspective review aims to explore the novel potential of hydrogels as bioadhesives for wound closure in the oral cavity.

Methods

This review thoroughly examines the properties, applications, and limitations of hydrogels as bioadhesive materials for wound closure within the human body.

Results

We first provide a comprehensive description of materials used for sutureless oral surgery. Next, drawing on our expertise in the field of oral surgery, we propose novel potential applications for hydrogels in oral wound closure. We showed that Hydrogels represent promising bioadhesives in medical field and are undergoing continuous enhancement to expand their applications in wound closure.

Conclusion

Although hydrogels have been utilized in various dental conditions, their potential for closing wounds in the oral cavity remains unexplored.

Advances and Functional Integration of Hydrogel Composites as Drug Delivery Systems in Contemporary Dentistry

This study explores the recent advances of and functional insights into hydrogel composites, materials that have gained significant attention for their versatile applications across various fields, including contemporary dentistry. Hydrogels, known for their high water content and biocompatibility, are inherently soft but often limited by mechanical fragility. Key areas of focus include the customization of hydrogel composites for biomedical applications, such as drug delivery systems, wound dressings, and tissue engineering scaffolds, where improved mechanical properties and bioactivity are critical. In dentistry, hydrogels are utilized for drug delivery systems targeting oral diseases, dental adhesives, and periodontal therapies due to their ability to adhere to the mucosa, provide localized treatment, and support tissue regeneration. Their unique properties, such as mucoadhesion, controlled drug release, and stimuli responsiveness, make them ideal candidates for treating oral conditions. This review highlights both experimental breakthroughs and theoretical insights into the structure-property relationships within hydrogel composites, aiming to guide future developments in the design and application of these multifunctional materials in dentistry. Ultimately, hydrogel composites represent a promising frontier for advancing materials science with far-reaching implications in healthcare, environmental technology, and beyond.

Hydrogel Coatings of Implants for Pathological Bone Repair

Hydrogels are well-suited for biomedical applications due to their numerous advantages, such as excellent bioactivity, versatile physical and chemical properties, and effective drug delivery capabilities. Recently, hydrogel coatings have developed to functionalize bone implants which are biologically inert and cannot withstand the complex bone tissue repair microenvironment. These coatings have shown promise in addressing unique and pressing medical needs. This review begins with the major functionalized performance and interfacial bonding strategy of hydrogel coatings, with a focus on the novel external field response properties of the hydrogel. Recent advances in the fabrication strategies of hydrogel coatings and their use in the treatment of pathologic bone regeneration are highlighted. Finally, challenges and emerging trends in the evolution and application of physiological environment-responsive and external electric field-responsive hydrogel coatings for bone implants are discussed.

Applications of Hydrogels in Drug Delivery for Oral and Maxillofacial Diseases

Oral and maxillofacial diseases have an important impact on local function, facial appearance, and general health. As a multifunctional platform, hydrogels are widely used in the biomedical field due to their excellent physicochemical properties. In recent years, a large number of studies have been conducted to adapt hydrogels to the complex oral and maxillofacial environment by modulating their pore size, swelling, degradability, stimulus-response properties, etc. Meanwhile, many studies have attempted to use hydrogels as drug delivery carriers to load drugs, cytokines, and stem cells for antibacterial, anticancer, and tissue regeneration applications in oral and maxillofacial regions. This paper reviews the application and research progress of hydrogel-based drug delivery systems in the treatment of oral and maxillofacial diseases such as caries, endodontic diseases, periodontal diseases, maxillofacial bone diseases, mucosal diseases, oral cancer, etc. The characteristics and applications of hydrogels and drug-delivery systems employed for the treatment of different diseases are discussed in order to provide a reference for further research on hydrogel drug-delivery systems in the future.

Advances in Multifunctional Bioactive Coatings for Metallic Bone Implants

To fix the bone in orthopedics, it is almost always necessary to use implants. Metals provide the needed physical and mechanical properties for load-bearing applications. Although widely used as biomedical materials for the replacement of hard tissue, metallic implants still confront challenges, among which the foremost is their low biocompatibility. Some of them also suffer from excessive wear, low corrosion resistance, infections and shielding stress. To address these issues, various coatings have been applied to enhance their in vitro and in vivo performance. When merged with the beneficial properties of various bio-ceramic or polymer coatings remarkable bioactive, osteogenic, antibacterial, or biodegradable composite implants can be created. In this review, bioactive and high-performance coatings for metallic bone implants are systematically reviewed and their biocompatibility is discussed. Updates in coating materials and formulations for metallic implants, as well as their production routes, have been provided. The ways of improving the bioactive coating performance by incorporating bioactive moieties such as growth factors, osteogenic factors, immunomodulatory factors, antibiotics, or other drugs that are locally released in a controlled manner have also been addressed.

Bioactive Coatings on Titanium: A Review on Hydroxylation, Self-Assembled Monolayers (SAMs) and Surface Modification Strategies

Titanium (Ti) and its alloys have been demonstrated over the last decades to play an important role as inert materials in the field of orthopedic and dental implants. Nevertheless, with the widespread use of Ti, implant-associated rejection issues have arisen. To overcome these problems, antibacterial properties, fast and adequate osseointegration and long-term stability are essential features. Indeed, surface modification is currently presented as a versatile strategy for developing Ti coatings with all these challenging requirements and achieve a successful performance of the implant. Numerous approaches have been investigated to obtain stable and well-organized Ti coatings that promote the tailoring of surface chemical functionalization regardless of the geometry and shape of the implant. However, among all the approaches available in the literature to functionalize the Ti surface, a promising strategy is the combination of surface pre-activation treatments typically followed by the development of intermediate anchoring layers (self-assembled monolayers, SAMs) that serve as the supporting linkage of a final active layer. Therefore, this paper aims to review the latest approaches in the biomedical area to obtain bioactive coatings onto Ti surfaces with a special focus on (i) the most employed methods for Ti surface hydroxylation, (ii) SAMs-mediated active coatings development, and (iii) the latest advances in active agent immobilization and polymeric coatings for controlled release on Ti surfaces.

Analytical Techniques for the Characterization of Bioactive Coatings for Orthopaedic Implants

The development of bioactive coatings for orthopedic implants has been of great interest in recent years in order to achieve both early- and long-term osseointegration. Numerous bioactive materials have been investigated for this purpose, along with loading coatings with therapeutic agents (active compounds) that are released into the surrounding media in a controlled manner after surgery. This review initially focuses on the importance and usefulness of characterization techniques for bioactive coatings, allowing the detailed evaluation of coating properties and further improvements. Various advanced analytical techniques that have been used to characterize the structure, interactions, and morphology of the designed bioactive coatings are comprehensively described by means of time-of-flight secondary ion mass spectrometry (ToF-SIMS), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), atomic force microscopy (AFM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), 3D tomography, quartz crystal microbalance (QCM), coating adhesion, and contact angle (CA) measurements. Secondly, the design of controlled-release systems, the determination of drug release kinetics, and recent advances in drug release from bioactive coatings are addressed as the evaluation thereof is crucial for improving the synthesis parameters in designing optimal bioactive coatings.

Pre-Clinical Models in Implant Dentistry: Past, Present, Future

Biomedical research seeks to generate experimental results for translation to clinical settings. In order to improve the transition from bench to bedside, researchers must draw justifiable conclusions based on data from an appropriate model. Animal testing, as a prerequisite to human clinical exposure, is performed in a range of species, from laboratory mice to larger animals (such as dogs or non-human primates). Minipigs appear to be the animal of choice for studying bone surgery around intraoral dental implants. Dog models, well-known in the field of dental implant research, tend now to be used for studies conducted under compromised oral conditions (biofilm). Regarding small animal models, research studies mostly use rodents, with interest in rabbit models declining. Mouse models remain a reference for genetic studies. On the other hand, over the last decade, scientific advances and government guidelines have led to the replacement, reduction, and refinement of the use of all animal models in dental implant research. In new development strategies, some in vivo experiments are being progressively replaced by in vitro or biomaterial approaches. In this review, we summarize the key information on the animal models currently available for dental implant research and highlight (i) the pros and cons of each type, (ii) new levels of decisional procedures regarding study objectives, and (iii) the outlook for animal research, discussing possible non-animal options.

Surface Treatment of the Dental Implant with Hyaluronic Acid: An Overview of Recent Data

Recently, interest has grown by focusing on the evaluation of a molecule already produced in the human body such as hyaluronic acid (HA), as an application to the surface of the titanium implant. Its osteo-conductive characteristics and positive interaction with the progenitor cells responsible for bone formation, consequently, make it responsible for secondary stability. The aim of this work was to analyze the various surface treatments in titanium implants, demonstrating that the topography and surface chemistry of biomaterials can correlate with the host response; also focusing on the addition of HA to the implant surface and assessing the biological implications during early stages of recovery. Used as a coating, HA acts on the migration, adhesion, proliferation and differentiation of cell precursors on titanium implants by improving the connection between implant and bone. Furthermore, the improvement of the bioactivity of the implant surfaces through HA could therefore facilitate the positioning of the dental prosthesis precisely in the early loading phase, thus satisfying the patients’ requests. It is important to note that all the findings should be supported by further experimental studies in animals as well as humans to evaluate and confirm the use of HA in any field of dentistry.

The application of hyaluronic acid in bone regeneration

Hyaluronic acid (HA) exists naturally as an important component of the extracellular matrix (ECM) in the human body. In recent decades, HA has been widely used in bone regeneration, and is currently a popular topic, particularly in the craniofacial and dental fields. From maxilla augmentation to craniofacial bone trauma, there is now a large demand for bone regenerative therapy. Serving as a cell-seeding scaffold or a carrier for bioactive components, hyaluronic acid-incorporated scaffolds and carriers in bone regeneration can be fabricated into either rigid or colloidal forms. Since the type of material used is a critical factor in the biological properties of a scaffold, HA derivatives or HA-incorporated composite scaffolds have shown excellent potential for improving osteogenesis and mineralization. Furthermore, in order to better enhance osteogenesis, local delivery carriers based on hyaluronic acid derivatives, rather than specifically serving as scaffolds, can be established by loading different osteoinductive or osteogenetic components and acquiring different release patterns. Such osteoinductive carriers immobilized on implant surfaces are also effective in improving osseointegration. Thus, as such a competent biomaterial, hyaluronic acid should be considered a promising tool in bone regeneration.

Osteogenic inducer sustained-release system promotes the adhesion, proliferation, and differentiation of osteoblasts on titanium surface

OBJECTIVE

Biomaterial can be locally applied to promote the osseointegration of dental implants. This study aimed to fabricate an osteogenic inducer (OI) sustained-release system and to evaluate its effects on the adhesion, proliferation, and differentiation of osteoblasts on titanium surfaces.

METHODS

First of all, different contents of OI solution were added to the poly (lactic-co-glycolic acid) (PLGA) gel individually to investigate the best physical properties and drug-release rate. Moreover, osteoblasts were isolated from the calvaria of two-month-old New Zealand rabbits through sequential enzymatic digestion. Osteoblasts were seeded onto the surface of Ti disks (control group), Ti coated with PLGA gel (PLGA group), and Ti coated with the OI sustained-release system (PLGA+OI group). Cell adhesion was observed by scanning electron microscopy. Cell proliferation was analyzed by cell counting kit-8. Cell differentiation was tested by alizarin red staining, alkaline phosphatase (ALP) activity and osteogenic-related gene expression.

RESULTS

The OI sustained-release system contained 15% OI solution had appropriate physical properties and drug-release rate. The osteoblasts in the PLGA+OI group were in a typical spindle shape with a considerable number indicating the promotion of adhesion and proliferation. The expression of early and late stage osteoblast differentiation genes in the PLGA+OI group were significantly higher than that of the control group and PLGA group at each time point. The PLGA group showed accelerated adhesion and differentiation but reduced proliferation compared with the control.

CONCLUSION

The OI sustained-release system promotes the adhesion, proliferation, and differentiation of osteoblasts on titanium surfaces. This system is a cost-effective osteoconductive biomaterial that might be promising for use in dental implantation.

Advances in Carbon Nanotubes-Hydrogel Hybrids in Nanomedicine for Therapeutics

In spite of significant advancement in hydrogel technology, low mechanical strength and lack of electrical conductivity have limited their next-level biomedical applications for skeletal muscles, cardiac and neural cells. Host-guest chemistry based hybrid nanocomposites systems have gained attention as they completely overcome these pitfalls and generate bioscaffolds with tunable electrical and mechanical characteristics. In recent years, carbon nanotube (CNT)-based hybrid hydrogels have emerged as innovative candidates with diverse applications in regenerative medicines, tissue engineering, drug delivery devices, implantable devices, biosensing, and biorobotics. This article is an attempt to recapitulate the advancement in synthesis and characterization of hybrid hydrogels and provide deep insights toward their functioning and success as biomedical devices. The improved comparative performance and biocompatibility of CNT-hydrogels hybrids systems developed for targeted biomedical applications are addressed here. Recent updates toward diverse applications and limitations of CNT hybrid hydrogels is the strength of the review. This will provide a holistic approach toward understanding of CNT-based hydrogels and their applications in nanotheranostics.