The increasing prevalence of peri-implantitis has led to a growing clinical use of implantoplasty, a procedure involving intraoral machining of the dental implant sur-face to remove biofilm. The absence of standardized clinical protocols may contribute to premature fatigue failure of dental implants. The present study aimed to determine the influence of machining depth on the cyclic mechanical behavior of dental im-plants. A total of 250 commercially pure Grade 3 titanium dental implants were dis-tributed into four groups according to machining depth: untreated (original), 0.2 mm, 0.4 mm, and 0.6 mm wall reduction. The implant system featured an internal connec-tion with a thread height of 0.4 mm. Finite element analysis was performed for each machining depth to evaluate Von Mises stress distribution and to simulate fatigue be-havior. The numerical models were validated through experimental fatigue testing using a servohydraulic MTS Bionix testing machine under ISO 14801:2016 standard conditions. Fractographic analysis was conducted by scanning electron microscopy. The results revealed that maximum Von Mises stresses were concentrated at the junc-tion between the implant thread and the implant body. The fatigue limit of the un-treated implants was approximately 400 N. Implants subjected to 0.4 mm machining exhibited a fatigue limit of 350 N, whereas lower fatigue limits were observed for 0.2 mm (290 N) and 0.6 mm (180 N) reductions. These findings demonstrate the signifi-cant mechanical effect of thread removal. At higher applied loads, fracture occurred in the coronal region of the implant, whereas at lower loads failure shifted to the im-plant–abutment connection. Finite element predictions showed high agreement with experimental results. The findings highlight a clinically relevant criterion: implanto-plasty depth should not exceed the original thread height, as excessive wall reduction markedly compromises fatigue resistance and long-term mechanical reliability.

One of the key factors for hard tissue regeneration is to develop mineralized fibrous scaffolds. These scaffolds can provide a micro-environment resembling the structure and mechanical properties of the extracellular matrix (ECM) of hard tissues favorable for subsequent cell responses and tissue regeneration. During biomineralization, amorphous precursor phases of calcium phosphate infiltrate into preformed collagen fibrils, and upon crystallization, the collagen fibrils are embedded with oriented hydroxyapatite (HA) nanocrystals. We previously demonstrated that hydrogels made of elastin-like recombinamers (ELRs) can template mineralization where minerals were selectively deposited into their frameworks. In this work, we focus on mimicking the nanostructure of the mineralized tissues, namely the intra- and extrafibrillar mineralized collagen fibrils, using the synthetic ELRs. We first electrospun the ELRs into nanofibers and then biomimetically mineralized them via the polymer-induced liquid-precursor (PILP) process. We tested two different ELRs one with a peptide sequence derived from the salivary protein statherin (st-ELR) and a reference one lacking the statherin sequence (ref-ELR). X-ray diffractometry (XRD) and Energy-dispersive X-Ray Spectroscopy (EDS) verified the mineral phase in the ELR nanofibers was HA. Scanning and Transmission Electorn Microscopy (SEM and TEM) analyses revealed that HA nanocrystals were infiltrated into and randomly oriented within the ELR nanofibers. The elastic modulus and hardness of the mineralized ELR nanofibers was increased significantly compared to unmineralized ELR. The mineralized nanofibers promoted the proliferation and osteogenic differentiation of pre-osteoblasts. These results support that a scaffold obtained using this biomimetic strategy and made of mineralized ELR electrospun nanofibers with controlled mineralization and improved mechanical properties has great potential for being used in hard tissue regeneration, such as craniofacial and periodontal and perimplant regeneration as well as tertiary dentin regeneration, as it mimics the structure and mechanical properties of collagen-HA nanocomposites.

Background/Objectives: One-piece (monoblock) dental implants are increasingly used, particularly in patients with limited bone availability. Prosthetic alignment is often achieved via plastic deformation of the titanium implant. This study aimed to evaluate the impact of such deformation-induced residual stress on the corrosion resistance of these implants. Methods: Two types of monoblock dental implants (spherical “S” and Mag-Conical “M”) were subjected to controlled plastic deformation. Residual stress was quantified by X-ray diffraction using the Bragg–Brentano method. Electrochemical behavior was evaluated by measuring the open-circuit potential (EOCP) and performing potentiodynamic polarization tests in phosphate-buffered saline (PBS) at 37 °C. Metal ion release (Ti, V, Al) was quantified by inductively coupled plasma mass spectrometry (ICP-MS) at specific immersion time points. Surface morphology and corrosion features were examined by scanning electron microscopy (SEM). Results: Residual stress values increased significantly after plastic deformation. The open-circuit potential (EOCP) shifted towards more electronegative values in both implant designs as deformation-induced residual stresses increased. The EOCP values shifted from −0.099 V to −0.227 V in the S design and from −0.115 V to −0.141 V in the M design, comparing the as-received condition with the deformed state, respectively. Potentiodynamic tests showed an increase in corrosion rate from 0.0021 mm/year for the original implants to 0.0156 mm/year for the deformed ones. Surfaces in the stressed regions exhibited a high density of corrosion pits, indicating localized electrochemical degradation. Deformed dental implants also exhibited higher ion release, particularly of titanium and vanadium, with higher levels observed in implants with greater residual stress and lower corrosion resistance. In the deformed regions, the release of titanium and vanadium ions into the surrounding medium was nearly five-fold higher. Conclusions: Plastic deformation of monoblock dental implants is associated with reduced corrosion resistance. Increased residual stress correlates with enhanced electrochemical degradation and ion release, which may have relevant implications for implant selection and clinical placement.

OBJECTIVES:This study evaluated the effects of incorporating fluoride-doped calcium phosphate (FDCP) into a glass ionomer cement (GIC) and a resin-modified glass ionomer cement (RMGIC) on their physicochemical properties, mineralisation potential, and antibacterial behaviour. METHODS:A conventional GIC (Riva SC, SDI Ltd., Australia) and RMGIC (Riva LC, SDI Ltd, Australia) were used to prepare experimental formulations containing different FDCP concentrations (SC 6%, SC 11 %, LC 13 %, and LC 18 %) and were compared with unmodified controls (SC-CTR, LC-CTR). Water sorption, solubility, uptake, pH, calcium and fluoride release, compressive strength and modulus, setting time, and microhardness were assessed. Mineral deposition on material surfaces and demineralised dentine was analysed using FTIR-ATR, SEM-EDX, and XRD after storage in artificial saliva (30 days). Antibacterial activity against Streptococcus gordonii was evaluated by metabolic activity, colony-forming units, and SEM. Cytotoxicity was assessed using human gingival fibroblasts. RESULTS:FDCP incorporation stabilised pH and influenced ion release behaviour in both materials. Increased mineral deposition was observed in FDCP-modified groups, with evidence of apatite-like precipitation, particularly in SC 11 %, LC 13 %, and LC 18 %. Improvements in long-term compressive strength and microhardness were mainly observed in the RMGIC formulations (LC 13 % and LC 18 %), as well as reduced bacterial metabolic activity and surface colonisation. However, reduced fibroblasts viability was also observed in all the tested groups under the test conditions. CONCLUSIONS:The incorporation of FDCP enhanced several functional properties of RGICs, particularly mineralisation and antibacterial behaviour, although some cytotoxic effects were also observed in all tested materials. CLINICAL SIGNIFICANCE:FDCP-modified GICs may improve the overal performance of GI-based restorative materials in clinical situations, as well as remineralisation and antibacterial activity.

OBJECTIVE:Stress shielding and bacterial infection are among the main challenges associated with metallic implants. To address these limitations, a Ti-35Nb-4Ag alloy was produced by powder metallurgy, combining a low elastic modulus (67.9 ± 1.1 GPa) with silver incorporated in solid solution to provide antibacterial activity. METHODS:Compression testing was performed to determine the elastic modulus. Roughness, wettability, and surface free energy with its dispersive and polar components were determined. The cytocompatibility study was carried out in accordance with ISO 10993-5, using commercially pure grade 4 titanium as a control. Adhesion and proliferation studies were carried out with human fibroblast cells (hFFS) for 2, 4, 7, and 14 days. Antibacterial studies were performed on three Gram-positive bacterial strains: Streptococcus gordonii, Staphylococcus aureus, and Enterococcus faecalis. The colonies formed (CFU) and the metabolic activity were assessed. RESULTS:The results showed that there were no statistically significant differences in roughness between the different metals tested. However, the Ti-35Nb-4Ag alloy had a lower contact angle (46°) than titanium (62°), and the surface energy was higher for the alloy (58 mJ/m²) than for titanium (41 mJ/m²). The increase in the polar component of the alloy (29 mJ/m2) compared to pure titanium (16 mJ/m2) was noteworthy. The alloy also showed enhanced fibroblast adhesion and proliferation while maintaining excellent cytocompatibility. In addition, the Ti-35Nb-4Ag alloy exhibited significantly lower CFU counts and bacterial metabolic activity than commercially pure titanium. SIGNIFICANCE:The Ti-35Nb-4Ag alloy combines a low elastic modulus, favourable surface properties, good cytocompatibility, and antibacterial activity, making it a promising candidate for hard tissue replacement.

Periodontitis is a pathogenic microbial-infected disease where immune dysregulation promotes chronic inflammation and excessive osteoclast activity, causing progressive tissue destruction. Current therapeutic approaches face challenges in achieving sustained drug release in periodontal pockets. In this study, we construct a self-assembled peptide hydrogel by combining negatively charged peptide amphiphile (PA) with positively charged antimicrobial peptide GL13K, namely PA/GL13K. GL13K electrostatically binds to self-assembled PA nanofibers, promoting PA self-assembly that yields a denser hydrogel network. This structural reinforcement enables sustained GL13K release. The PA/GL13K hydrogel demonstrates potent antibacterial effects and immunomodulatory properties, suppressing pro-inflammatory M1 macrophage polarization while promoting anti-inflammatory M2 macrophage activation. Moreover, the PA/GL13K hydrogel inhibits osteoclast differentiation in vitro. In an experimental periodontitis mouse model, local periodontal injection of the PA/GL13K hydrogel reduced inflammatory infiltration and osteoclast-mediated bone resorption, effectively mitigating periodontal tissue destruction. These findings suggest that the self-assembled peptide hydrogel system may represent a potential multifunctional therapeutic approach for periodontal treatment. Statement of significance This study presents a peptide-based hydrogel system designed for the comprehensive treatment of periodontitis, addressing critical challenges in current therapeutic strategies. The self-assembled charge-complementary hydrogel is composed of negatively charged peptide amphiphile (PA) and positively charged antimicrobial peptide GL13K. GL13K electrostatically binds to self-assembled PA nanofibers, promoting PA self-assembly that yields a denser hydrogel network. This structural reinforcement enables sustained GL13K release. The system demonstrates synergistic effects, including antibacterial activity, immunomodulatory effects, and inhibition of osteoclastogenesis. Our findings highlight the hydrogel’s potential as a promising platform for periodontitis management, combining structural optimization with multifunctional therapeutic outcomes.

The increasing prevalence of peri-implantitis has led to a growing clinical use of implantoplasty, a procedure involving intraoral machining of the dental implant surface to remove biofilm. The absence of standardized clinical protocols may contribute to premature fatigue failure of dental implants. The present study aimed to evaluate the influence of machining depth on the cyclic mechanical behavior of dental implants. A total of 250 commercially pure grade 4 titanium dental implants were distributed into four groups according to machining depth: untreated (original), 0.2 mm, 0.4 mm, and 0.6 mm wall reduction. The implant system featured an internal connection with a thread height of 0.4 mm. Finite element analysis was performed for each machining depth to evaluate von Mises stress distribution and simulate fatigue behavior. The numerical models were validated through experimental fatigue testing using a servo-hydraulic MTS Bionix testing machine under ISO 14801:2016 conditions, showing a high correlation between simulated and experimental results (correlation coefficients > 0.9). The results indicated that maximum von Mises stresses were concentrated at the junction between the implant thread and the implant body. The fatigue limit of the untreated implants was approximately 351 N. Implants subjected to 0.4 mm machining exhibited a fatigue limit of 301 N, whereas lower fatigue limits were observed for 0.2 mm (255 N) and 0.6 mm (185 N) reductions. These findings suggest a significant mechanical effect of thread removal: 0.4 mm implantoplasty may provide improved fatigue performance compared to 0.2 mm, potentially due to reduced stress concentration at the thread-body junction. At high applied loads, fracture occurred in the coronal region of the implant, whereas at lower loads failure shifted to the implant-abutment connection. Although a good agreement between numerical and experimental results was observed, these findings should be interpreted with caution due to the in vitro testing conditions and the assumptions inherent to the finite element simulations. Therefore, while the results suggest that implantoplasty depth should not exceed the original thread height, further validation under clinically relevant conditions is required to confirm its impact on long-term mechanical reliability.

Bone adhesives have emerged as promising alternatives for complex fracture fixation. However, discrepancies between material degradation rates and the physiological timeline of bone healing remain a critical limitation. Here, a polyurethane-based adhesive (TNC) was developed, synthesized from trimeric hexamethylene diisocyanate, nano-hydroxyapatite, and type I collagen. The TNC demonstrates strong initial adhesion to both wet and blood-contaminated bone surfaces and exhibits excellent biocompatibility. A distinguishing feature of TNC is its capacity to synchronize degradation with the stages of bone healing. During degradation, TNC forms a mineralized surface layer that releases calcium ions. The calcium ions activate cathepsin K, an enzyme integral to bone remodeling. This calcium-mediated mechanism accelerates TNC degradation by 1.9-fold during the remodeling phase compared to the initial phase. In a rat skull fracture model, TNC supported effective fracture stabilization and achieved favorable bone regeneration at 8 weeks after implantation. These findings demonstrate that TNC combines early mechanical stability with phase-specific degradability to facilitate bone regeneration in a temporally-controlled manner. The present work provides a framework for the development of bio-responsive bone adhesives that synchronize degradation behavior with healing phases for orthopedic applications.

Volumetric muscle loss (VML) often leads to irreversible functional impairment due to limited endogenous regeneration and poor outcomes of current therapies. Collagen fibers are piezoelectric biomaterials and key components of the skeletal muscle extracellular matrix. With excellent biocompatibility, deformability, and capacity to promote myocyte proliferation and differentiation, collagen holds great promise for muscle repair and regeneration. However, the inherently weak piezoelectricity, structural disorder, and insufficient mechanical properties limit the practical application. This study introduces a co-assembly strategy using gallic acid (GA) to enhance the piezoelectric performance of collagen through interactions between the phenolic hydroxyl groups of GA and collagen, which may contribute to a more ordered hydrogen-bonding network and promote the oriented arrangement of phenolic hydroxyl groups. On this basis, a collagen fiber-based piezoelectric material (CFPM) was fabricated by combining salting-out and pre-stretching, exhibiting stable piezoelectric output, skeletal muscle-matched mechanical properties, and an anisotropic structure. Under ultrasound activation, CFPM generates electrical signals that synergize with topological cues to promote myoblast differentiation and the formation of aligned myotubes. In a rat VML model, CFPM implantation with ultrasound significantly enhances muscle regeneration, reduces fibrosis, and improves functional recovery. Collectively, the enhanced piezoelectric collagen with aligned microstructure developed in this study represents a promising biomaterial strategy for VML repair.

Dental implants have become an increasingly popular solution for the replacement of missing teeth in partially or fully edentulous patients. However, one of the most common causes of implant failure is peri-implantitis, an inflammatory disease with a reported prevalence of up to 34 %. With the rising number of dental implant placements across all population groups, the prevention and management of peri-implantitis has gained significant importance, both from a health and economic perspective. The global dental implant market is valued at approximately USD 3.5 billion, underscoring the need for effective strategies to prevent and treat this condition. Current approaches to managing peri-implantitis include both surgical and non-surgical methods, such as mechanical debridement and antibiotic therapy. Recently, plasma technology has emerged as a promising alternative in the field of dentistry due to its bactericidal properties, lack of toxic residues, and reduced risk of inducing antimicrobial resistance. This review focuses on the existing in vitro, in vivo, and clinical studies that explore the use of plasma treatment for the control of peri-implantitis. Special attention is given to the application of plasma irradiation on dental implants or abutments prior to their placement as a potential preventive strategy. The ultimate goal is to assess their effectiveness in improving bone regeneration and soft tissue attachment with a view to controlling peri-implantitis.

Background/Objectives: Peri-implantitis is a common complication affecting approximately 24% of dental implants and is characterized by progressive bone loss and reduced implant stability. Implantoplasty, an intraoral procedure used to remove biofilm by machining the titanium implant surface, has become increasingly common in clinical practice. However, this procedure may compromise the mechanical integrity of implants, especially when combined with peri-implant bone loss, potentially leading to premature fatigue failure. This study evaluated the effect of different marginal bone resection depths, with and without implantoplasty, on the cyclic mechanical behavior of dental implants. Methods: A total of 200 commercially pure grade 4 titanium implants were embedded in resin simulating human bone at depths of 3, 4, and 5 mm. A subset of implants underwent implantoplasty with a 0.4 mm surface reduction corresponding to the thread width. Finite element analysis was performed to evaluate von Mises stress distribution and predict fatigue behavior. Numerical results were experimentally validated using a servo-hydraulic MTS Bionix system under ISO 14801:2016 conditions. Fatigue limits were determined from the asymptotic region of the load-cycles-to-failure (S-N) curves, and fracture surfaces were examined by scanning electron microscopy. Results: Maximum von Mises stresses were concentrated at the thread-body transition and increased with greater marginal resection depth, with additional stress amplification observed after implantoplasty. Fatigue limits for untreated implants were approximately 351 N, 285 N, and 210 N for 3-, 4-, and 5 mm resections, respectively. Implants subjected to 0.4 mm implantoplasty showed fatigue limits of 311 N, 270 N, and 90 N, respectively. Failure patterns were load-dependent: higher loads produced coronal fractures, whereas lower loads resulted in failure at the implant-abutment connection. Finite element predictions showed strong agreement with the experimental results. Conclusions: Excessive marginal resection significantly decreases the fatigue resistance and long-term mechanical reliability of dental implants, particularly when combined with implantoplasty. The main limitations of this study include is in vitro design, the assumptions inherent to the numerical models, and the variability associated with implantoplasty procedures.

ABSTRACTObjectivesThis study evaluated different designs of the conical implant‐abutment connection (IAC) and their resistance to microgap formation under oblique loads as specified by the ISO standard for testing dental implants. Also evaluated was the effect of deviations from the ISO specifications on the outcomes.MethodsFinite element analysis was conducted to compare the microgap formation and stress distribution among three conical IAC designs (A, B, and C) in two loading configurations: one compliant with ISO 14801 and one with a modified load adaptor (non‐ISO). The different IAC designs varied in the taper, diameter, and cone height. The cone angle mismatch (Cam) between the implant and abutment was considered. A torque of 20 Ncm and oblique loads (up to 400 N) were simulated.ResultsThe stresses produced by the screw‐tightening torque varied among the different IAC designs. The contact height was approximately 0.3 mm for Designs A and B, and less than 0.03 mm for Design C. Under oblique loads, Design A maintained IAC sealing without gap formation up to 400 N. With the ISO adaptor, gaps appeared in Design B at 300 N and in Design C at 90 N. The non‐ISO adaptor resulted in gap formation at 160 N for Design B and at 50 N for Design C.ConclusionsThe IAC design and cone angle mismatch significantly influenced microgap formation, with some designs showing zero gaps even when the oblique load reached 400 N. The non‐ISO adaptor increased gap formation in IACs B and C.

Biomedical and dental implants have enhanced healthcare but concurrently increased the risk of infections. Innovations in smart biomaterials, especially those responding to light stimuli through photocatalytic mechanisms, are emerging as promising solutions for activating targeted antimicrobial responses. While extensive reviews have provided insight into photocatalysis and its medical and environmental applications, limited focus has been given to solutions specifically tailored for implant contexts. The recent introduction of photocatalysis in the implant field, particularly visible-light-triggered photocatalytic coatings, represents a versatile approach to managing infections. These coatings offer on-demand reactive oxygen species generation, delivering antibacterial effects against a range of pathogens. Hence, this comprehensive review aims to summarize the latest advancements in design principles, physicochemical modifications, and surface optimizations, along with novel research concepts towards the achievement of visible-light-triggered photocatalytic antibacterial activity. Moreover, through a systematic search, this review discusses the current state-of-the-art regarding the antimicrobial efficacy of these biomaterials and the key factors influencing their performance, including microorganism type, photocatalyst properties, light source and intensity, and exposure time. Finally, it provides an in-depth discussion of current challenges, future directions, and regulatory considerations targeting biofilm-related implant treatments, offering guidance for future clinical adoption of multifunctional photocatalytic coatings in implant therapy.

This review evaluates the effect of magnesium (Mg)-doped coatings on the osseointegration of titanium (Ti)-based implants. The recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses and the PRISMA 2020 Statement were followed, with registration in PROSPERO (CRD42024572571). The PICOS strategy was based on population: dental implants; intervention: Mg coatings; control: surfaces without Mg; outcomes: bone-implant contact (BIC), bone area (BA), implant stability coefficient (ISQ), and removal torque (RTQ); and study Design: in vivo studies. The SYRCLE tool was used to assess the risk of bias of animal studies. Meta-analyses were performed, using a random-effect model and 95% confidence interval. Twenty-three records were included, and 21 were enrolled in the meta-analyses. The most commonly used Mg doping method was microarc oxidation. The Mg-doped coatings, significantly favored pooled BIC values in animals [-6.09 (-8.35, -3.82), I2: 50%, p < 0.00001], especially up to 3, 4, 6, and 8 weeks compared to surfaces without Mg. Interestingly, Mg-doped coatings favored BA up to 6 weeks [-8.20 (-14.31, -2.09), I2: 0%, p = 0.008], and RTQ up to 3 [-8.44 (-12.33, -4.56), I2: 63%, p < 0.0001]. Conversely, it did not influence ISQ [-0.24 (-2.05, 1.58), I2: 88%, p = 0.80]. Mg-doped coatings significantly enhanced osseointegration in dental implants by improving BIC, BA, and RTQ, while showing no impact on ISQ. Supported by studies across various animal species, these results confirm that such coatings represent an effective and safe approach for promoting bone integration.

Implant-associated infections, primarily resulting from bacterial colonization, represent a significant challenge that frequently leads to implant failure. Antibacterial coatings, particularly those incorporating antimicrobial peptides (AMPs), offer a promising strategy for mitigating these infections. However, the application methods for these coatings—whether chemical or physical—face considerable challenges regarding stability and efficacy. In this study, we introduce a novel approach that employs zinc oxide nanoparticles (ZnONP) as an intermediary physical adhesive layer between titanium implants and the self-assembled AMP GL13K. The incorporation of ZnONP enhances hydrogen bonding interactions, facilitated by the nanostructured interface and the abundant hydroxyl groups on the ZnONP surface, thereby significantly improving the stability of the coating. Additionally, GL13K and ZnONP demonstrate synergistic antibacterial and immunomodulatory effects, as validated through in vitro and in vivo studies. The enhanced stability of the coating, combined with improved antibacterial, anti-inflammatory, and osteogenic properties, collectively promotes osseointegration of mini-implants in a rat tibia infection model. Given the adaptability of this nanocoating system with other nanoparticles to further enhance hydrogen bonding, we propose it as a potential versatile solution for the supramolecular peptide coating of a diverse range of medical devices.

Transcutaneous devices such as dental implants frequently fail due to infections at their interfaces with epithelial tissues. These infections are facilitated by the lack of integration between the devices and the surrounding soft tissues. This study aims to improve epithelial integration through surface modification of a transcutaneous implant material (polyetheretherketone (PEEK)). The modification involved covalent bonding of collagen via two distinct methods: (1) nonselective binding through any primary amines present on collagen using carbodiimide-based coupling and (2) site-specific binding to the free amine on the N-terminus of collagen molecules. The second approach preserves active sites responsible for interacting with integrins, crucial for epithelial cell adhesion, located near the C terminus. Both conjugation methods resulted in similar amounts of immobilized collagen; yet, surfaces with 2-PCA-based collagen conjugation exhibited 4 times more free amines. This indicates that fewer amines were used for conjugation in these samples, confirming that 2-PCA selectively binds collagen only through the N-terminus amines. Collagen-conjugated surfaces significantly enhanced HaCaT epithelial cell viability and adhesion compared to unmodified PEEK. Furthermore, 2-PCA-based conjugation resulted in a 2-fold increase in β4 subunit gene expression of integrin α6β4 (a key epithelial cell adhesion marker), higher integrin β4 immunofluorescence (IF) intensity, and over a 30% improvement in cell retention following mechanical detachment, compared to nonselective conjugation. These findings suggest that selective collagen conjugation on PEEK surfaces increases the accessibility of collagen domains responsible for binding with integrin receptors, which in turn improves epithelial cell attachment, offering a promising strategy for reducing infections and enhancing the longevity of transcutaneous devices.

Percutaneous medical devices - such as prosthetic limbs, dental implants, and subgingival dental restorations - commonly fail due to their susceptibility to infection, posing serious morbidity and mortality and a significant economic burden. Current solutions for subgingival dental restoration failure - such as antimicrobial and degradation-resistant materials - remain largely experimental and have yet to achieve widespread clinical translation. Thus, as a next-generation strategy for improving subgingival restoration longevity, we draw inspiration from the tooth, a long-lasting percutaneous organ with robust soft tissue attachment enabled by cell-matrix adhesive hemidesmosomes (HDs). Promoting HD formation around subgingival restorations - mimicking the natural attachment seen in teeth - may extend dental restoration lifespan by fostering a stable mucosal barrier that blocks bacterial access. A family of scalable biologics-free HD instructive light-curable biosealants (HILBs) was engineered for point-of-care coating for subgingival restorations to trigger and guide beneficial pericellular extracellular matrix structural changes at the HILB surface. Material-based strategies for medical device integration with the human body have traditionally focused on controlling surface properties to provoke desired cellular and tissue responses at the bio/non-bio interface. However, this approach overlooks the evolving pericellular matrix that quickly enrobes cells and overrides engineered surface cues. The control of cell-secreted nascent matrix through HILB surface polarity markedly upregulated HD formation. This bioinstruction is dependent on nascent glycoprotein laminin332 secretion and recognized by HD integrins, which demonstrates the potential of biomaterial surface design to guide secreted pericellular matrix with implications for facilitating tissue repair and enhancing subgingival restoration outcomes.

Regeneration of the multiple tissues and interfaces in the periodontal complex necessitates multidisciplinary evaluation to establish structure/function relationships. This article, an initiative of the Academy of Dental Materials, provides guidance for performing chemical, structural, and mechanical characterization of materials for periodontal tissue regeneration, and outlines important recommendations on methods of testing bioactivity, biocompatibility, and antimicrobial properties of biomaterials/scaffolds for periodontal tissue engineering. First, we briefly summarize periodontal tissue engineering fabrication methods. We then highlight critical variables to consider when evaluating a material for periodontal tissue regeneration, and the fundamental tests used to investigate them. The recommended tests and designs incorporate relevant international standards and provide a framework for characterizing newly developed materials focusing on the applicability of those tests for periodontal tissue regeneration. The most common methods of biofabrication (electrospinning, injectable hydrogels, fused deposition modelling, melt electrowriting, and bioprinting) and their specific applications in periodontal tissue engineering are reviewed. The critical techniques for morphological, chemical, and mechanical characterization of different classes of materials used in periodontal regeneration are then described. The major advantages and drawbacks of each assay, sample sizes, and guidelines on specimen preparation are also highlighted. From a biological standpoint, fundamental methods for testing bioactivity, the biocompatibility of materials, and the experimental models for testing the antimicrobial potential are included in this guidance. In conclusion, researchers performing studies on periodontal tissue regeneration will have this guidance as a tool to assess essential properties and characteristics of their materials/scaffold-based strategies.