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In this work, we show the in vitro anticancer potential of surgical wires, obtained from zinc (ZnMg0.004) or magnesium (MgCa0.7) alloys by spatial technology comprising casting, extrusion, and final drawing processes. We also present the selective anticancer effects of applied soluble multilayer nanocoatings of zinc and magnesium onto titanium surfaces using the pulse laser deposition method. In the latter, the titanium samples were produced via 3D printing using the selective laser melting method and coated with various combinations of zinc and magnesium layers. For cytotoxicity studies, human dental pulp-derived stem cells (hDPSCs) and human osteosarcoma SaOS-2 cell line were used as representatives of healthy and cancer cells. Cells were examined against the 0.3–3.0 cm2/mL material extract ratios obtained from experimental and steel surgical wires, the latter being the current clinical industry standard. The MgCa0.7 alloy wires were approx. 1.5 times more toxic to cancer cells at all examined extract ratios vs. the extracts from steel surgical wires that exhibited comparable toxicity towards healthy and cancer cells. The ZnMg0.004 alloy wires displayed increased toxicity towards cancer cells with decreasing extract ratios. This was also reflected in the increased anticancer effectiveness, calculated based on the viability ratio of healthy cells to cancer cells, from 1.1 to 4.0 times. Healthy cell viability remained at 80–100%, whereas cancer cell survival fluctuated at 20–75%, depending on the extract ratio. Furthermore, the culture of normal or cancer cells on the surface of Zn/Mg-coated titanium allowed us to select combinations of specific coating layers that yielded a comparable anticancer effectiveness to that observed with the experimental wires that ranged between 2 and 3. Overall, this work not only demonstrates the substantial anticancer properties of the studied wires but also indicates that similar anticancer effects can be replicated with appropriate nanocoatings on titanium samples. We believe that this work lays the groundwork for the future potential development of the category of new implants endowed with anticancer properties.

Titanium implants undergo an aging process through surface hydrocarbon deposition, resulting in decreased wettability and bioactivity. Plasma treatment was shown to significantly reduce surface hydrocarbons, thus improving implant hydrophilicity and enhancing the osseointegration process. This study investigates the effect of plasma surface treatment on bone-to-implant contact (BIC) of implants presenting a nanostructured calcium-incorporated surface (XPEED®). Following a Randomized Controlled Trial (RCT) design, patients undergoing implant surgery in the posterior maxilla received additional plasma-treated (n = 7) or -untreated (n = 5) 3.5 × 8 mm implants that were retrieved after a 4-week healing period for histological examination. Histomorphometric analysis showed that plasma-treated implants exhibited a 38.7% BIC rate compared to 22.4% of untreated implants (p = 0.002), indicating enhanced osseointegration potential. Histological images also revealed increased bone formation and active osteoblastic activity around plasma-treated implants when compared to untreated specimens. The findings suggest that plasma treatment improves surface hydrophilicity and biological response, facilitating early bone formation around titanium implants. This study underscores the importance of surface modifications in optimizing implant integration and supports the use of plasma treatment to enhance osseointegration, thereby improving clinical outcomes in implant dentistry and offering benefits for immediate and early loading protocols, particularly in soft bone conditions.

Background context. Dental implants are designed to replace a missing tooth. Implant stability is vital to achieving osseointegration and successful implantation. Although there are many implants available on the market, there is room for improvement. Purpose. We describe a new dental implant with improved primary stability features. Study design. Lab bench test studies. Methods. We evaluated the new implant using static and flexion–compression fatigue tests with compression loads, 35 Ncm tightening torque, displacement control, 0.01 mm/s actuator movement speed, and 9–10 Hz load application frequency, obtaining a cyclic load diagram. We applied variable cyclic loadings of predetermined amplitude and recorded the number of cycles until failure. The test ended with implant failure (breakage or permanent deformation) or reaching five million cycles for each load. Results. Mean stiffness was 1151.13 ± 133.62 SD N/mm, mean elastic limit force 463.94 ± 75.03 SD N, and displacement 0.52 ± 0.04 SD mm, at failure force 663.21 ± 54.23 SD N and displacement 1.56 ± 0.18 SD mm, fatigue load limit 132.6 ± 10.4 N, and maximum bending moment 729.3 ± 69.43 mm/N. Conclusions. The implant fatigue limit is satisfactory for incisor and canine teeth and between the values for premolars and molars for healthy patients. The system exceeds five million cycles when subjected to a 132.60 N load, ensuring long-lasting life against loads below the fatigue limit.

Titanium is considered to be the most essential metal in the field of implantology. The main factors determining metal biocompatibility, among others, include the morphology and chemical composition of the titanium surface. Therefore, the aim of this work was to develop approaches to control the biological activity of the titanium surface by creating coatings that combine both an inorganic phase with a given morphology and organic molecules containing an integrin-selective peptide that regulate cell adhesion and proliferation. As such, we synthesized new c(RGDfC) derivatives of amino acid bisphosphonates (four examples) with different bisphosphonate anchors and maleimide linkers. These molecules were deposited on a highly developed porous surface obtained via the plasma electrolytic oxidation (PEO) of coarse-grained and nanostructured titanium. In vitro studies demonstrated the increase in the viability degree of mesenchymal stem cells and fibroblasts on the surface of coarse-grained or nanostructured titanium modified with PEO and a c(RGDfC) derivative of ε-aminocaproic acid bisphophonate with an SMCC linker. As a result, the use of conjugates of amino acid bisphosphonates with a cyclic RGD peptide for the modification of PEO-coated titanium opens the ways for the effective control of the biological activity of the metal implant surface.

Pure titanium and titanium alloys are widely used in dentistry and orthopedics. However, despite their outstanding mechanical and biological properties, implant failure mainly due to post-operative infection still remains a significant concern. The possibility to develop inherent antibacterial medical devices was here investigated by covalently inserting bioactive ammonium salts onto the surface of titanium metal substrates. Titanium discs have been functionalized with quaternary ammonium salts (QASs) and with oleic acid (OA), affording the Ti-AEMAC Ti-GTMAC, Ti-AUTEAB, and Ti-OA samples, which were characterized by ATR-FTIR and SEM-EDX analyses and investigated for the roughness and hydrophilic behavior. The chemical modifications were shown to deeply affect the surface properties of the metal substrates and, as a consequence, their bio-interaction. The bacterial adhesion tests against the Gram-negative Escherichia Coli and Gram-positive Staphylococcus aureus, at 1.5 and 24 h of bacterial contact, showed good anti-adhesion activity for Ti-AUTEAB and Ti-OA samples, containing a long alkyl chain between the silicon atom and the ammonium functionality. In particular, the Ti-AUTEAB sample showed inhibition of bacteria adhesion against Escherichia Coli of about one log with respect to the other samples, after 1.5 h. The results of this study highlight the importance of chemical functionalization in addressing the antimicrobial activity of metal surfaces and could open new perspectives in the development of inherent antibacterial medical devices.

Objectives. The purpose of this work was to determine the influence of residual alumina after sand blasting treatment in titanium dental implants. This paper studied the effect of alumina on physico-chemical surface properties, such as: surface wettability, surface energy. Osseointegration and bacteria adhesion were determined in order to determine the effect of the abrasive particles. Materials and Methods. Three surfaces were studied: (1) as-received, (2) rough surface with residual alumina from sand blasting on the surface and (3) with the same roughness but without residual alumina. Roughness was determined by white light interferometer microscopy. Surface wettability was evaluated with a contact angle video-based system and the surface free energy by means of Owens and Wendt equation. Scanning electron microscopy equipped with microanalysis was used to study the morphology and determine the chemical composition of the surfaces. Bacteria (Lactobacillus salivarius and Streptococcus sanguinis) were cultured in each surface. In total, 110 dental implants were placed into the bone of eight minipigs in order to compare the osseointegration. The percentage of bone-to-implant contact was determined after 4 and 6 weeks of implantation with histometric analysis. Results. The surfaces with residual alumina presented a lower surface free energy than clean surfaces. The in vivo studies demonstrated that the residual alumina accelerated bone tissue growth at different implantation times, in relation to clean dental implants. In addition, residual alumina showed a bactericidal effect by decreasing the quantity of bacteria adhering to the titanium. Conclusions. It is possible to verify the benefits that the alumina (percentages around 8% in weight) produces on the surface of titanium dental implants. Clinical relevance. Clinicians should be aware of the benefits of sand-blasted alumina due to the physico-chemical surface changes demonstrated in in vivo tests.

Titanium specimens have been proven to be safe and effective biomaterials in terms of their osseo-integration. To improve the bioactivity and develop customized implants titanium, the surface can be modified with selective laser melting (SLM). Moreover, the design of macro-porous structures has become popular for reaching a durable bone fixation. 3D-printed titanium (Titanium A, B, and C), were cleaned using an organic acid treatment or with electrochemical polishing, and were characterized in terms of their surface morphology using scanning electron microscopy. Next, Dental Pulp Stem Cells (DPSCs) were cultured on titanium in order to analyze their biocompatibility, cell adhesion, and osteoconductive properties. All tested specimens were biocompatible, due to the time-dependent increase of DPSC proliferation paralleled by the decrease of LDH released. Furthermore, data highlighted that the open cell form with interconnected pores of titanium A, resembling the inner structure of the native bone, allows cells to better adhere inside the specimen, being proteins related to cell adherence highly expressed. Likewise, titanium A displays more suitable osteoconductive properties, being the profile of osteogenic markers improved compared to titanium B and C. The present work has demonstrated that the inner design and post-production treatments on titanium surfaces have a dynamic influence on DPSC behavior toward adhesion and osteogenic commitment.

The surface modification of titanium (Ti) can enhance the osseointegration and antibacterial properties of implants. In this study, we modified porous Ti discs with calcium phosphate (CaP) and different concentrations of Lactoferrin (LF) by biomimetic mineralization and examined their antibacterial effects and osteogenic bioactivity. Firstly, scanning electron microscopy (SEM), the fluorescent tracing method, X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), and the releasing kinetics of LF were utilized to characterize the modified Ti surface. Then, the antibacterial properties against S. sanguis and S. aureus were investigated. Finally, in vitro cytological examination was performed, including evaluations of cell adhesion, cell differentiation, extracellular matrix mineralization, and cytotoxicity. The results showed that the porous Ti discs were successfully modified with CaP and LF, and that the LF-M group (200 μg/mL LF in simulated body fluid) could mildly release LF under control. Further, the LF-M group could effectively inhibit the adhesion and proliferation of S. sanguis and S. aureus and enhance the osteogenic differentiation in vitro with a good biocompatibility. Consequently, LF-M-modified Ti may have potential applications in the field of dental implants to promote osseointegration and prevent the occurrence of peri-implantitis.

Cellularized scaffold is emerging as the preferred solution for tissue regeneration and restoration of damaged functionalities. However, the high cost of preclinical studies creates a gap between investigation and the device market for the biomedical industry. In this work, bone-tailored scaffolds based on the Ti6Al4V alloy manufactured by electron beam melting (EBM) technology with reused powder were investigated, aiming to overcome issues connected to the high cost of preclinical studies. Two different elementary unit cell scaffold geometries, namely diamond (DO) and rhombic dodecahedron (RD), were adopted, while surface functionalization was performed by coating scaffolds with single layers of polycaprolactone (PCL) or with mixture of polycaprolactone and 20 wt.% hydroxyapatite (PCL/HA). The mechanical and biological performances of the produced scaffolds were investigated, and the results were compared to software simulation and experimental evidence available in literature. Good mechanical properties and a favorable environment for cell growth were obtained for all combinations of scaffold geometry and surface functionalization. In conclusion, powder recycling provides a viable practice for the biomedical industry to strongly reduce preclinical costs without altering biomechanical performance.

In this study, an integrated approach was used for the preparation of a nanotitanium-based bioactive material. The integrated approach included three methods: severe plastic deformation (SPD), chemical etching and atomic layer deposition (ALD). For the first time, it was experimentally shown that the nature of the etching medium (acidic or basic Piranha solutions) and the etching time have a significant qualitative impact on the nanotitanium surface structure both at the nano- and microscale. The etched samples were coated with crystalline biocompatible TiO2 films with a thickness of 20 nm by Atomic Layer Deposition (ALD). Comparative study of the adhesive and spreading properties of human osteoblasts MG-63 has demonstrated that presence of nano- and microscale structures and crystalline titanium oxide on the surface of nanotitanium improve bioactive properties of the material.

Bioactive manganese (Mn)-doped ceramic coatings for intraosseous titanium (Ti) implants are developed. Arc plasma deposition procedure is used for coatings preparation. X-ray Diffraction, Scanning Electron Microscopy-Energy Dispersive X-ray Spectroscopy, and Electron Paramagnetic Resonance (EPR) methods are applied for coatings characterization. The coatings are homogeneous, composed of the main phase α-tricalcium phosphate (α-TCP) (about 67%) and the minor phase hydroxyapatite (about 33%), and the Mn content is 2.3 wt%. EPR spectroscopy demonstrates that the Mn ions are incorporated in the TCP structure and are present in the coating in Mn2+ and Mn3+ oxidation states, being aggregated in clusters. The wetting contact angle of the deposited coatings is suitable for cells’ adhesion and proliferation. In vitro soaking in physiological solution for 90 days leads to a drastic change in phase composition; the transformation into calcium carbonate and octacalcium phosphate takes place, and no more Mn is present. The absence of antibacterial activity against Escherichia coli, Enterococcus faecalis, and Pseudomonas aeruginosa bacteria strains is observed. A study of the metabolic activity of mouse fibroblasts of the NCTC L929 cell line on the coatings using the MTT (dye compound 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) test demonstrates that there is no toxic effect on the cell culture. Moreover, the coating material supports the adhesion and proliferation of the cells. A good adhesion, spreading, and proliferative activity of the human tooth postnatal dental pulp stem cells (DPSC) is demonstrated. The developed coatings are promising for implant application in orthopedics and dentistry.

Coating of plasma chemical oxidized titanium (TiOB®) with gentamicin-tannic acid (TiOB® gta) has proven to be efficient in preventing bacterial colonization of implants. However, in times of increasing antibiotic resistance, the development of alternative antimicrobial functionalization strategies is of major interest. Therefore, the aim of the present study is to evaluate the antibacterial and biocompatible properties of TiOB® functionalized with silver nanoparticles (TiOB® SiOx Ag) and ionic zinc (TiOB® Zn). Antibacterial efficiency was determined by agar diffusion and proliferation test on Staphylocuccus aureus. Cytocompatibility was analyzed by direct cultivation of MC3T3-E1 cells on top of the functionalized surfaces for 2 and 4 d. All functionalized surfaces showed significant bactericidal effects expressed by extended lag phases (TiOB® gta for 5 h, TiOB® SiOx Ag for 8 h, TiOB® Zn for 10 h). While TiOB® gta (positive control) and TiOB® Zn remained bactericidal for 48 h, TiOB® SiOx Ag was active for only 4 h. After direct cultivation for 4 d, viable MC3T3-E1 cells were found on all surfaces tested with the highest biocompatibility recorded for TiOB® SiOx Ag. The present study revealed that functionalization of TiOB® with ionic zinc shows bactericidal properties that are comparable to those of a gentamicin-containing coating.

Objectives: The aim of this study was to perform an in vivo histological comparative evaluation of bone formation around titanium (machined and treated surface) and zirconia implants. For the present study were used 50 commercially pure titanium implants grade IV, being that 25 implants with a machined surface (TiM group), 25 implants with a treated surface (TiT group) and, 25 implants were manufactured in pure zirconia (Zr group). The implants (n = 20 per group) were installed in the tibia of 10 rabbits. The implants distribution was randomized (n = 3 implants per tibia). Five implants of each group were analyzed by scanning electron microscopy and an optical laser profilometer for surface roughness characterization. Six weeks after the implantation, 10 implants for each group were removed in counter-torque for analysis of maximum torque value. The remaining samples were processed, included in historesin and cut to obtain non-decalcified slides for histomorphological analyses and histomorphometric measurement of the percentage of bone-implant contact (BIC%). Comparisons were made between the groups using a 5% level of significance (p < 0.05) to assess statistical differences. The results of removal torque values (mean ± standard deviation) showed for the TiM group 15.9 ± 4.18 N cm, for TiT group 27.9 ± 5.15 N cm and for Zr group 11.5 ± 2.92 N cm, with significant statistical difference between the groups (p < 0.0001). However, the BIC% presented similar values for all groups (35.4 ± 4.54 for TiM group, 37.8 ± 4.84 for TiT group and 34.0 ± 6.82 for Zr group), with no statistical differences (p = 0.2171). Within the limitations of the present study, the findings suggest that the quality of the new bone tissue formed around the titanium implants present a superior density (maturation) in comparison to the zirconia implants.

Manipulation of implant surface characteristics constitutes a promising strategy for improving cell growth and tissue response on a variety of materials with different surface topographies. Mesenchymal progenitor cells with a capacity to respond to titanium surface stimuli and differentiate into osteoblasts were used to perform comparative tests between two different implant topographies, including their functional interaction with pre-osteoblasts directly seeded onto the implants. Functional analysis of nanostructured implant surfaces was performed by in vitro assay analysis. The machined surface of titanium implants (mach group) was used as a control and compared with a nanoparticle HA activated surface implant (nano group), developed by the deposition of pure crystalline hydroxyapatite. Cell culture on the nano group surface resulted in higher cell adhesion and cultured osteoblast viability compared with the mach group. Scanning electron microscope (SEM) images revealed a stable interaction, indicated by the presence of focal cell adhesion formation. These results together with positive mineralization assays showed the nano group to be an excellent scaffold for bone-implant integration.